If you are a long time user of contact lenses you are already well aware of its many benefits. If you are considering a switch over from your old spectacles to contact lenses, let us inform you, you are going in the right direction. Over 30 million people in the USA are believed to use contact lenses, either as an alternative of the traditional spectacle or for some cosmetic purposes. If you too are thinking of stepping into their shoes, then try to equip yourself with as much information about the contact lenses as possible; it will help you to find out the right product suitable for your needs and take the informed decision at the time of purchase.
First of all, you may want to know about the actual definition of the contact lens. According to FDA definition, a contact lens is a prescribed medical device, which is usually placed on the cornea of the eye and used either for corrective or cosmetic or therapeutic purposes.
There are countless benefits of contact lenses. Contact lenses perform the same corrective functions as the conventional glasses, but as opposed to the glasses, contact lenses are virtually weightless and most importantly they are invisible. So they are regarded to be more comfortable than the traditional spectacles.
Then consider the contact lenses from an ophthalmologic point of view: As contact lenses move with your eyes they provide a better field of view. Like the glasses, there are no frames to obstruct your vision and thus they reduce distortions to a considerable point. Sometimes your vision is obstructed as the lenses of your glass get blurred by moisture, rain or dirt; you will find no such faults with your contact lenses.
Do you follow an active lifestyle and every time your spects come into the way of your active lifestyle? Then contact lens can be the only solution for you. If you are in any kind of sports including swimming, diving or athletics, a contact lens can offer you a distortion free clear vision at the time of your movements, without any kind of side effects. It is properly fitted inside your eyes so that it does not affect your concentration in any way.
There are many people, particularly the women who find the glasses to be great hindrance for showing off the natural beauty of their faces. On the other hand, contact lens provides utter ease and comfort and they do not come into the way you look.
You can get modern contact lenses with UV protection built into the material, so if you want protection for your eyes, you can opt for these lenses instead of wearing goggles.
There are people with eternal dissatisfaction over the color of their eyes and they find in the contact lens the golden opportunity to mend the nature to get the color of their dreams.
Part II
So you have almost taken the decision in favor of buying contact lenses after reading about the many benefits of contact lenses! But wait; let's inform you about the many types of contact lenses you might come across in the market.
In these days contact lenses are made of variety of plastic materials-- but at the core they are of two main types: soft or rigid gas permeable.
Soft Lenses: These contact lenses contain some 25% to 79% water. They are easily to adaptable to your eyes and hence are quite comfortable. With a soft contact lens in your eyes you will barely feel that there is something foreign in your eyes. However, you should be more careful in handling them and they have to be replaced more frequently.
Rigid gas permeable (RGP) lenses: These lenses take time to adapt to your eyes. But they have much greater resistance power against deposit buildup. With RGP you are supposed to get sharper vision. They are more durable too. Thus, at the beginning RGP may appear to be costlier, but because of its longer lifespan, RGP gives you better value for your money.
Daily Disposable Lenses: If you want the ultimate convenience, you must go for disposable contact lenses. The cleaning and disinfection procedures with disposable contact lenses are extremely simplified. They are better for your eye health because they are more frequently replaced. Also you always have some spare lenses with you. These days you get the disposable contact lenses in all toric, bifocal, and colored versions. Only you have to be cautious in your handling of these lenses. And for all these benefits you should be ready to pay some extra bucks.
Toric Soft Lenses: These lenses are claimed to correct astigmatism. You can get these types both in daily wear as well as planned replacement versions. You may be required to visit the doctor's clinic more than once to get a perfect fitting.
Color contact lenses: Then there are those colored lenses that are mainly used for cosmetic purposes. You can get mainly four different types of cored contact lenses, namely, visibility tints, enhancement tints, opaque color tints and light-filtering tints. If you have no vision problem, you can take the 'Plano' form of colored contact lenses that do not make any visual correction. You can also get them as disposable or frequent replacement lens.
However there is no hard and fast rule for buying the contact lenses from your eye specialist. You can buy them from any reliable optical stores. You can also try out in the online stores where you can avail the scope of wide comparison. But one important thing to consider, no matter wherever you buy the contact lenses from, your decision should be guided by the value of the product and not only the price.
2007年9月30日星期日
How To Choose A Digital Camera - Gimme My Options!
Digital cameras cost anywhere from tens to thousands of dollars, with all of them having excellent components and will be a good one. What it boils down to is what is it a person wants, and what eventually will suit their needs. The new word on the block is "prosumer" cameras - referring to cameras and their equipment focused on mainly advanced amateurs, a very inelegant word but getting the point across.
According to unbiased consumer reports, the leading brands about price, quality, and guarantees are Canon, Fujifilm, HP, Kodak, Nikon, Olympus, and Sony - with other brands coming from consumer-electronics, computer, traditional film, and film companies.
To avoid being stuck with this, recognize there is no such thing as a perfect camera. What is perfect is not what is the "top pick" but one that is the absolute most suitable one of all of them - for me - not the majority of the consumers. Choosing a digital camera from lists from the random choices of reviewers and camera critics is not the way to go, believe me, as they do not take a person's needs into account with the most updated information available. Each camera comes with its own individual features like image resolution, storage capacity, lens power etc. So, what should the buyer look for in the camera?
The first step is thinking about what is needed and wanted. Look at various specifications - and recognize they are not always straightforward facts for all the cameras at once. An example is the number of pixels the sensor records on the cameras. We assume that a 5 Mp camera will give higher quality results than a 3 Mp, but this may not be true.
Questions need to be asked and looked in their entirety, not just one at a time. Some of these questions are: (1) what type of camera user am I?; (2) how important is camera size, megapixels, and finished picture size to me?; (3) what are the lens options to me?; (4) what are my memory choices, and how much do I need?; and (5) is money an issue, and how much can I pay or should I pay? A digital camera should last for about two or three years before upgrading; I need to look at the camera and how long it has lasted its present owners.
Many factors need to be considered when a buying a digital camera. Look at the online information of digital camera web sites and suitable models of what you want. Then go to your local camera store and handle the actual camera. Get a feel of it, and if it fits comfortably in your hands. Look at its build, its quality, and what it accessories it has.
Talk to the camera professionals that are working there, or even people you know who actually owns one. Look at some of the reviews of the camera you want; do not decide to purchase based on their reviews - only how they feel AFTER they have purchased it. What problems have they had? Would they buy another one? What guarantees does it have, and do they honor it? What is their return time on answering questions or repair work?
Resolution is another major requirement - I need to ask myself how much flexibility would I need to enlarge my images? Are 4x6 or 8x10 pictures what I want - if so, I need to choose the camera accordingly, as the quality of the camera is directly proportional to the resolution of its images. For 4x6 photographs, the 4 or 5 MP (megapixels) is adequate, yet can still do the 8x10 photographs without a lot of image distortion; any enlargements would require a 6 to 8 MP camera.
The 3 megapixels camera outputs images that are anywhere from 1 to 2 MB in size while a 7 MP camera outputs images that are 4 to 5 MB in size. A gentle rule of thumb is if I was a professional photographer then I would go for high pixel cameras; if I was a beginners I can look at low or mid-end cameras.
None of us want to think about our camera malfunctioning or breaking down entirely before we ever purchase one for any length of time, but it can and probably will happen at some time. If this does happen, make sure the camera's manufacturer will guarantee this, and for how long after the purchase? If they do, they will exchange the new camera for the broken one if requested, and then pass the defective camera onto there servicing department. It will be fixed and sent to the outlet warehouse, completely functional.
Many deals for consumers can be found this way, at a newer and lower price for a fully functional and almost new camera. For amateurs and novice users, restored products such as these are popular for a lower price, and still has a warranty that is slightly limited.
According to unbiased consumer reports, the leading brands about price, quality, and guarantees are Canon, Fujifilm, HP, Kodak, Nikon, Olympus, and Sony - with other brands coming from consumer-electronics, computer, traditional film, and film companies.
To avoid being stuck with this, recognize there is no such thing as a perfect camera. What is perfect is not what is the "top pick" but one that is the absolute most suitable one of all of them - for me - not the majority of the consumers. Choosing a digital camera from lists from the random choices of reviewers and camera critics is not the way to go, believe me, as they do not take a person's needs into account with the most updated information available. Each camera comes with its own individual features like image resolution, storage capacity, lens power etc. So, what should the buyer look for in the camera?
The first step is thinking about what is needed and wanted. Look at various specifications - and recognize they are not always straightforward facts for all the cameras at once. An example is the number of pixels the sensor records on the cameras. We assume that a 5 Mp camera will give higher quality results than a 3 Mp, but this may not be true.
Questions need to be asked and looked in their entirety, not just one at a time. Some of these questions are: (1) what type of camera user am I?; (2) how important is camera size, megapixels, and finished picture size to me?; (3) what are the lens options to me?; (4) what are my memory choices, and how much do I need?; and (5) is money an issue, and how much can I pay or should I pay? A digital camera should last for about two or three years before upgrading; I need to look at the camera and how long it has lasted its present owners.
Many factors need to be considered when a buying a digital camera. Look at the online information of digital camera web sites and suitable models of what you want. Then go to your local camera store and handle the actual camera. Get a feel of it, and if it fits comfortably in your hands. Look at its build, its quality, and what it accessories it has.
Talk to the camera professionals that are working there, or even people you know who actually owns one. Look at some of the reviews of the camera you want; do not decide to purchase based on their reviews - only how they feel AFTER they have purchased it. What problems have they had? Would they buy another one? What guarantees does it have, and do they honor it? What is their return time on answering questions or repair work?
Resolution is another major requirement - I need to ask myself how much flexibility would I need to enlarge my images? Are 4x6 or 8x10 pictures what I want - if so, I need to choose the camera accordingly, as the quality of the camera is directly proportional to the resolution of its images. For 4x6 photographs, the 4 or 5 MP (megapixels) is adequate, yet can still do the 8x10 photographs without a lot of image distortion; any enlargements would require a 6 to 8 MP camera.
The 3 megapixels camera outputs images that are anywhere from 1 to 2 MB in size while a 7 MP camera outputs images that are 4 to 5 MB in size. A gentle rule of thumb is if I was a professional photographer then I would go for high pixel cameras; if I was a beginners I can look at low or mid-end cameras.
None of us want to think about our camera malfunctioning or breaking down entirely before we ever purchase one for any length of time, but it can and probably will happen at some time. If this does happen, make sure the camera's manufacturer will guarantee this, and for how long after the purchase? If they do, they will exchange the new camera for the broken one if requested, and then pass the defective camera onto there servicing department. It will be fixed and sent to the outlet warehouse, completely functional.
Many deals for consumers can be found this way, at a newer and lower price for a fully functional and almost new camera. For amateurs and novice users, restored products such as these are popular for a lower price, and still has a warranty that is slightly limited.
Loire Valley Wines - Five Wine Appellations Sprinkled Among the Historic Chateaux
The Loire River in France winds through the Touraine area for almost one hundred kilometres dotted with many amazing French chateau open to the public and a wonderful location for a holiday. There are 5 AOC wines (Appelations d'origine Controlees - wines of controlled origin and quality) awarded throughout this area: Touraine, Touraine Amboise, Touraine Azay-le-Rideau, Touraine Mesland and the latest being Touraine Noble-Joue awarded its AOC status in 2001. The combination of vineyards and castle make the Touraine region of the Loire Valley an incredible destination for any wine lover and his or her family.
The Touraine Amboise vineyards totalling 236 hectares are situated between Tours and Blois extending along both banks of the Loire. The reds are a wild cherry colour produced from a blend of Cabernet and Gamay Noir and have scents of red fruits. Their palate is solid and full. The whites produced from Chenin Blanc give dry, medium and sweet white wines. Their straw yellow colour turns gold after 3 to 4 years of cellaring. Their aroma is all quince and honey and they have a supple palate because of the more mild climate that favours late-ripening grape varieties. The roses are light in colour with a bouquet of lilac and roses and are refreshing to taste and suitable for early drinking.
It is delightful to combine a day of tasting Touraine Amboise AOC wines with a visit to Chateau Close Luc, Leonardo da Vinci's castle now a museum with working models of many of his inventions and an amazing interactive park adored by children and Chateau Amboise which is da Vinci's final resting place.
The Touraine appellation covering 5,282 hectares differs depending on the terroir on the slopes of the River valleys. Half the production is red. The Cabernet and Gamay reds are cherry coloured. The Gamay has a strawberry or cherry flavour. They have a dominant fruitiness with discreet tannins and should be drunk within two years. The Cabernet red has a raspberry, green pepper and liquorice fragrance and can be laid down for 2 to 4 years because of its good tannic support. White wines made from Sauvignon produced mainly in the Cher valley are straw yellow in colour and have a floral fragrance with a touch of gooseberry or blackcurrant mingled with traces of spices. On the palate the sauvignon whites are delicately lively. The methode traditionnelle sparkling wines have mouth-filling flavours of apple and brioche.
The must see Chateau to visit in the region of this appellation is Chateau Chenonceau which spans the River Cher.
Touraine Mesland is situated west of Blois, planted on the slopes of the Loire facing Chateau de Chaumont, which holds an amazing garden festival each summer based on a different theme each year and definitely worth a visit especially if you have children tagging along.
The reds have a substantial taste and are the colour of a well-ripened cherry and have complex aromas of prunes and very ripe fruits. The roses sparkle with salmon highlights and have a fresh delicate aroma of spices and red fruits. They have a solid palate making them suitable to accompany a whole meal. The whites carry an aroma of pear and spices and are lively and round on the palate.
The appellation of Touraine Noble-Joue is only 25 hectares producing a characteristic rose with flower aromas of hyacinth and peony followed by notes of cherry, redcurrant and ripe pear. The rose palate is round with flavours of morello cherry and a dash of cloves.
The chenin blank whites of the five Touraine appellations are all straw yellow can be cellared for 5 to 15 years.
The Touraine Azay-le-Rideau is a small region totalling 45 hectares south-west of Tours stretching along the Indre valley between Montbazon and the Loire river producing whites and roses. The roses are dainty with an aroma of marshmallows, lilac, roses and almond. They are delightful and lively to drink in summer. The whites are fresh and have fruit and floral aromas of peach apricot and green apple with a soft mineral edge.
You must visit the spectacular Chateau du Azay-le-Rideau when in this appellation area. The chateau is turreted and surrounded by water which gives amazing reflections for the sound and light spectacle held in high season.
The Touraine Azay-le-Rideau is a small region totalling 45 hectares south-west of Tours stretching along the Indre valley between Montbazon and the Loire river producing whites and roses. The roses are dainty with an aroma of marshmallows, lilac, roses and almond. They are delightful and lively to drink in summer. The whites are fresh and have fruit and floral aromas of peach apricot and green apple with a soft mineral edge.
You must visit the spectacular Chateau du Azay-le-Rideau when in this appellation area. The chateau is turreted and surrounded by water which gives amazing reflections for the sound and light spectacle held in high season.
As well as these five AOC wines there is also Cheverney, Cour-Cheverney just South of Blois and Vouvray in the Touraine.
What better way to enjoy these lovely wines than driving through the Loire Valley visiting historic castles, maybe a hot-air balloon ride in the morning, gourmet lunch in village bistros, meeting cheese and wine producers sampling their products and returning at night to a friendly inviting boutique chateau hotel. Don't just visit a french castle - stay in one and truly experience the grandeur of living in a castle in France. You will be amazed. Make your next holiday a gourmet wine lovers castle holiday in the beautiful Loire Valley. If you love great wine you will not regret it.
The Touraine Amboise vineyards totalling 236 hectares are situated between Tours and Blois extending along both banks of the Loire. The reds are a wild cherry colour produced from a blend of Cabernet and Gamay Noir and have scents of red fruits. Their palate is solid and full. The whites produced from Chenin Blanc give dry, medium and sweet white wines. Their straw yellow colour turns gold after 3 to 4 years of cellaring. Their aroma is all quince and honey and they have a supple palate because of the more mild climate that favours late-ripening grape varieties. The roses are light in colour with a bouquet of lilac and roses and are refreshing to taste and suitable for early drinking.
It is delightful to combine a day of tasting Touraine Amboise AOC wines with a visit to Chateau Close Luc, Leonardo da Vinci's castle now a museum with working models of many of his inventions and an amazing interactive park adored by children and Chateau Amboise which is da Vinci's final resting place.
The Touraine appellation covering 5,282 hectares differs depending on the terroir on the slopes of the River valleys. Half the production is red. The Cabernet and Gamay reds are cherry coloured. The Gamay has a strawberry or cherry flavour. They have a dominant fruitiness with discreet tannins and should be drunk within two years. The Cabernet red has a raspberry, green pepper and liquorice fragrance and can be laid down for 2 to 4 years because of its good tannic support. White wines made from Sauvignon produced mainly in the Cher valley are straw yellow in colour and have a floral fragrance with a touch of gooseberry or blackcurrant mingled with traces of spices. On the palate the sauvignon whites are delicately lively. The methode traditionnelle sparkling wines have mouth-filling flavours of apple and brioche.
The must see Chateau to visit in the region of this appellation is Chateau Chenonceau which spans the River Cher.
Touraine Mesland is situated west of Blois, planted on the slopes of the Loire facing Chateau de Chaumont, which holds an amazing garden festival each summer based on a different theme each year and definitely worth a visit especially if you have children tagging along.
The reds have a substantial taste and are the colour of a well-ripened cherry and have complex aromas of prunes and very ripe fruits. The roses sparkle with salmon highlights and have a fresh delicate aroma of spices and red fruits. They have a solid palate making them suitable to accompany a whole meal. The whites carry an aroma of pear and spices and are lively and round on the palate.
The appellation of Touraine Noble-Joue is only 25 hectares producing a characteristic rose with flower aromas of hyacinth and peony followed by notes of cherry, redcurrant and ripe pear. The rose palate is round with flavours of morello cherry and a dash of cloves.
The chenin blank whites of the five Touraine appellations are all straw yellow can be cellared for 5 to 15 years.
The Touraine Azay-le-Rideau is a small region totalling 45 hectares south-west of Tours stretching along the Indre valley between Montbazon and the Loire river producing whites and roses. The roses are dainty with an aroma of marshmallows, lilac, roses and almond. They are delightful and lively to drink in summer. The whites are fresh and have fruit and floral aromas of peach apricot and green apple with a soft mineral edge.
You must visit the spectacular Chateau du Azay-le-Rideau when in this appellation area. The chateau is turreted and surrounded by water which gives amazing reflections for the sound and light spectacle held in high season.
The Touraine Azay-le-Rideau is a small region totalling 45 hectares south-west of Tours stretching along the Indre valley between Montbazon and the Loire river producing whites and roses. The roses are dainty with an aroma of marshmallows, lilac, roses and almond. They are delightful and lively to drink in summer. The whites are fresh and have fruit and floral aromas of peach apricot and green apple with a soft mineral edge.
You must visit the spectacular Chateau du Azay-le-Rideau when in this appellation area. The chateau is turreted and surrounded by water which gives amazing reflections for the sound and light spectacle held in high season.
As well as these five AOC wines there is also Cheverney, Cour-Cheverney just South of Blois and Vouvray in the Touraine.
What better way to enjoy these lovely wines than driving through the Loire Valley visiting historic castles, maybe a hot-air balloon ride in the morning, gourmet lunch in village bistros, meeting cheese and wine producers sampling their products and returning at night to a friendly inviting boutique chateau hotel. Don't just visit a french castle - stay in one and truly experience the grandeur of living in a castle in France. You will be amazed. Make your next holiday a gourmet wine lovers castle holiday in the beautiful Loire Valley. If you love great wine you will not regret it.
Information Systems For Organization Structure
A system of roles, relationships, responsibilities, power, authority, accountability and proper technology is what defines the structure of an organization. The power of an organization is rooted in its structure and its success is determined by its organizing ability. Information technology has made its mark to prove as a backbone to organizations organizing capabilities.
Every organization comes up with a product or a service. Its a common phenomenon that integrating products or services from various organizations gives an effective and useful device. Assembling, storing, pricing and managing information related to these activities in a storehouse posed problems since ages. With the advent of warehouse management systems, an improvement to the Data Warehouse. All information is maintained and managed with the WMS software.
Efficient algorithms are used for quick retrieval of space, pricing information, best fit calculations, randomizing and prioritizing tasks etc. This has provided organizations time to concentrate more on their supply chain rather than worrying about warehouse management.
Online business transactions have been going at good pace however the time gap between placing an order and receiving clearance is often an issue to worry about. This would consume a minimum of two business days. Marketing companies needed to organize much of their force to service these requests. With MS-speech server technology, orders are placed through voice and interfaces are provided to facilitate interactive sessions with the clients. The weight of servicing the client requests is reduced and organizations can devote much time for building their strategies.
Standards for communication and exchange of information are not defined for organizations. However there are many situations where information is to be shared and communication links have to be set up. Conversion into compatible formats was a tedious job which resulted in delay or information mismatch. With the interoperable specification software, companies can exchange information without concerning more about the problems of format conversion and network security.
With optical lines for communication added up with these IT developments the network systems are offering more bandwidths, which means more frequent flow of information and high data sharing capacities. Data warehouses can be used for predicting future demand, studying demand-supply analysis, competition among peers etc.
IT advancements have provided enough momentum for organizations to organize and devote time to develop their individual strategies, policies and mission Statements.
Culture and other moral values can be taught to employees to provide them peace at work. Management, bureaucracy, competition and environment are the four buzzwords that contribute for any organizations success. IT advancement provides a nice dynamic platform on which the organizations competitiveness can be assessed.
Every organization comes up with a product or a service. Its a common phenomenon that integrating products or services from various organizations gives an effective and useful device. Assembling, storing, pricing and managing information related to these activities in a storehouse posed problems since ages. With the advent of warehouse management systems, an improvement to the Data Warehouse. All information is maintained and managed with the WMS software.
Efficient algorithms are used for quick retrieval of space, pricing information, best fit calculations, randomizing and prioritizing tasks etc. This has provided organizations time to concentrate more on their supply chain rather than worrying about warehouse management.
Online business transactions have been going at good pace however the time gap between placing an order and receiving clearance is often an issue to worry about. This would consume a minimum of two business days. Marketing companies needed to organize much of their force to service these requests. With MS-speech server technology, orders are placed through voice and interfaces are provided to facilitate interactive sessions with the clients. The weight of servicing the client requests is reduced and organizations can devote much time for building their strategies.
Standards for communication and exchange of information are not defined for organizations. However there are many situations where information is to be shared and communication links have to be set up. Conversion into compatible formats was a tedious job which resulted in delay or information mismatch. With the interoperable specification software, companies can exchange information without concerning more about the problems of format conversion and network security.
With optical lines for communication added up with these IT developments the network systems are offering more bandwidths, which means more frequent flow of information and high data sharing capacities. Data warehouses can be used for predicting future demand, studying demand-supply analysis, competition among peers etc.
IT advancements have provided enough momentum for organizations to organize and devote time to develop their individual strategies, policies and mission Statements.
Culture and other moral values can be taught to employees to provide them peace at work. Management, bureaucracy, competition and environment are the four buzzwords that contribute for any organizations success. IT advancement provides a nice dynamic platform on which the organizations competitiveness can be assessed.
Multiple Sclerosis may affect you
What is Multiple sclerosis?
Multiple sclerosis, commonly known as MS, is an autoimmune disease that attacks the central nervous system. The central nervous system consists of optical nerves, the spinal cord and the brain.
Nerve fibers of the central nervous system are surrounded by fatty tissue called "myelin", which helps them control electrical impulses of the body. In MS, myelin is damaged at various places on nerve fibers, leaving scar tissue called sclerosis. The nerve fibers can be completely damaged or broken by this.
What causes multiple sclerosis is not known as yet, but a lot of research is being done at this point in time. Present research is indicating that the damage to myelin is caused by an abnormal response of the body's immune system. In normal cases, the body's immune system protects us from attacks from viruses and bacteria, but in multiple sclerosis the immune system attacks its own tissues, as if there simply was not enough cellular communication, or not good cell to cell communication.
This type of disease is referred to as an autoimmune disease.
A reason it is hard to diagnose in the early stages is that symptoms are not only different in every individual, they are different in the same person from time to time.
Symptoms may or may not include weakness, tingling, poor coordination of body parts, fatigue for long periods, blurry vision, involuntary movement of the eye (sometimes at a rapid pace), stiffness of muscles, slurred speech, bladder problems, difficulty in walking, decrease or increase in sensitivity to heat, loss of memory, reduction in logical thinking ability, problems with sexual function, depression and partial or complete paralysis of the body. These symptoms may go away on their own.
As multiple sclerosis is hard to diagnose in the beginning, a number of tests are needed to confirm the disease. Starting from the patient's medical history, a full neurological exam, magnetic resonance imaging of the brain, and study of the central nervous system through visual stimulation is conducted.
Sometimes, fluid is taken out of the substance surrounding the spinal cord to look at its composition.
When the medical histories of patients are examined, questions of the disease's hereditary nature are raised. Although research has not given a definite answer to this question, medical professionals do believe that family predisposition is a factor in the incidence of the disease.
Females are often found to be more susceptible to MS. When we look at the world it is often argued that multiple sclerosis is more common in mild climates than in tropical climates, but whether this can be proven or not is a different question.
Multiple sclerosis is often treated in two ways. The first is aimed at curing the disease itself and the second is the usage of drugs and techniques to reduce the impact and severity of the symptoms. People often think that those with multiple sclerosis will end up in a wheel chair sooner or later, but this is not necessarily true. Many people with this disease are able to walk for the rest of their lives. It is more likely, however, that sufferers will be in need of mobility devices as the disease progresses over a long period of time. Sometimes these devices are used by people to avoid injuries even though they are able to walk on their own.
http://www.ifoundhealth.com Copyright 2006-present: This copyrighted document may be reproduced and shared freely, only if the authors information remains and the links are live.
Multiple sclerosis, commonly known as MS, is an autoimmune disease that attacks the central nervous system. The central nervous system consists of optical nerves, the spinal cord and the brain.
Nerve fibers of the central nervous system are surrounded by fatty tissue called "myelin", which helps them control electrical impulses of the body. In MS, myelin is damaged at various places on nerve fibers, leaving scar tissue called sclerosis. The nerve fibers can be completely damaged or broken by this.
What causes multiple sclerosis is not known as yet, but a lot of research is being done at this point in time. Present research is indicating that the damage to myelin is caused by an abnormal response of the body's immune system. In normal cases, the body's immune system protects us from attacks from viruses and bacteria, but in multiple sclerosis the immune system attacks its own tissues, as if there simply was not enough cellular communication, or not good cell to cell communication.
This type of disease is referred to as an autoimmune disease.
A reason it is hard to diagnose in the early stages is that symptoms are not only different in every individual, they are different in the same person from time to time.
Symptoms may or may not include weakness, tingling, poor coordination of body parts, fatigue for long periods, blurry vision, involuntary movement of the eye (sometimes at a rapid pace), stiffness of muscles, slurred speech, bladder problems, difficulty in walking, decrease or increase in sensitivity to heat, loss of memory, reduction in logical thinking ability, problems with sexual function, depression and partial or complete paralysis of the body. These symptoms may go away on their own.
As multiple sclerosis is hard to diagnose in the beginning, a number of tests are needed to confirm the disease. Starting from the patient's medical history, a full neurological exam, magnetic resonance imaging of the brain, and study of the central nervous system through visual stimulation is conducted.
Sometimes, fluid is taken out of the substance surrounding the spinal cord to look at its composition.
When the medical histories of patients are examined, questions of the disease's hereditary nature are raised. Although research has not given a definite answer to this question, medical professionals do believe that family predisposition is a factor in the incidence of the disease.
Females are often found to be more susceptible to MS. When we look at the world it is often argued that multiple sclerosis is more common in mild climates than in tropical climates, but whether this can be proven or not is a different question.
Multiple sclerosis is often treated in two ways. The first is aimed at curing the disease itself and the second is the usage of drugs and techniques to reduce the impact and severity of the symptoms. People often think that those with multiple sclerosis will end up in a wheel chair sooner or later, but this is not necessarily true. Many people with this disease are able to walk for the rest of their lives. It is more likely, however, that sufferers will be in need of mobility devices as the disease progresses over a long period of time. Sometimes these devices are used by people to avoid injuries even though they are able to walk on their own.
http://www.ifoundhealth.com Copyright 2006-present: This copyrighted document may be reproduced and shared freely, only if the authors information remains and the links are live.
2007年9月29日星期六
How to Dimension a Telecommunication Network
Please see Greenfield Network Dimensioning before reading this.
The detailed dimensioning steps include:
Step 1: Disintegrate Demand Matrices
In general, as long as a layer is not the lowest transmission layer, it can have a native external demand matrix. Therefore, in a network probably there are multiple demand matrices that are in different network tributary levels. For example, in a network there can be an OC-3-tributary demand matrix in the OC-3 layer, and an OCH demand matrix in the Optical Channel (OCH) layer. Therefore, the dimensioning process is required to route all these demands independently layer by layer from top to bottom.
Step 2: Routing Client Layer Demands
For each demand in a client layer, Dijkstras routing algorithm is applied to find the shortest path based on the topology in the bottom transmission layer. Depending on the protection type, a second protection path may also be found for each demand. In addition, demand splitting may be supported. As a result, the routing process will generate a set of routes, through which the traffic demands are routed.
Step 3: Bundling
After all traffic demands on a low-rate client layer are routed, they may be bundled in a server layer. For a bundling process, a client layer and a server layer that are related to the bundling process should be designated first. There are three types of bundling strategies, including (1) end-to-end bundling, (2) link-by-link bundling, and (3) bundling reoptimization.
End-to-end bundling
The end-to-end bundling strategy is simple enough to multiplex low-rate tributaries in the client layer into high-rate capacity trunks in the server layer in an end-to-end fashion. The bundling process will generate an intermediate demand matrix for the server layer. For example, if seven units of tributaries in the OC-1 layer are bundled onto the OC-3 layer, the bundling process will generate three units of OC-3 tributaries in the OC-3 layer, which is a demand in the OC-3 layer.
Link-by-link bundling
In contrast to end-to-end bundling, link-by-link bundling bundles traffic demand on a physical-topology-link or server-layer-topology-link basis. That is, all the traffic demands are routed based on the physical topology first, and then all the demands on a physical link or server-layer link are bundled. For example, if there are seven units of OC-1 routed over a common physical link, then on the serve layer (e.g., OC-3 layer) three units of OC-3 need to be established between the two end nodes of the server link.
Bundling Re-optimization
After bundling, a re-optimization process can be carried out to decrease the number of bundling links in the server layer. The purpose of the re-optimization is to clear traffic on some server links that have few traffic demands, by rerouting these demands onto other server links. If all the traffic demands are successfully re-routed, these server links can be removed from the design, as they are carrying no traffic demands. Different re-optimization strategies can be applied respectively for end-to-end and link-by-link bundling.
Step 4: Integrate Demand Matrices on an Intermediate Server Layer
From a bundling process, an intermediate server layer can have internal demand matrices generated from upper-layer traffic demands. Also, each network layer can have its own native demand matrix, which composes demands of customers who require network capacity in tributary of the current layer. These two types of demand matrices have the same level of tributary and make up a total demand matrix in the intermediate server layer. Thus, the integration of these two types of demand matrix will generate a total demand matrix for the current intermediate layer. This new demand matrix will be used for the following routing and bundling steps.
Step 5: Route Integrated Demand Matrix and Bundling
An intermediate server can also be a client layer of another lower server layer. The previous obtained integrated traffic demand matrix should also be routed in the physical layer and bundled on the next server layer. Again, Dijkstras algorithm can be used to route the integrated demand matrix. Accordingly, a bundling and bundling re-optimization process can be performed to bundle the integrated traffic demands on the next server layer. The server layer is the current intermediate server layer. A similar demand matrix integration process can be further carried out to sum up an intermediate internal demand matrix and a native external demand matrix to form an integrated demand matrix for the current intermediate server layer. In summary, the above routing, bundling, and integration steps will be carried out recursively until the transmission layer. To that end, the dimensioning process is completed.
Step 6: Cost Evaluation, Equipment List, and Performance Analysis
Based on the previous network dimensioning, we can eventually make a total cost evaluation, list out all the equipment requirement and configuration, and make what-if analyses for the new design such as reliability and availability analyses.
The detailed dimensioning steps include:
Step 1: Disintegrate Demand Matrices
In general, as long as a layer is not the lowest transmission layer, it can have a native external demand matrix. Therefore, in a network probably there are multiple demand matrices that are in different network tributary levels. For example, in a network there can be an OC-3-tributary demand matrix in the OC-3 layer, and an OCH demand matrix in the Optical Channel (OCH) layer. Therefore, the dimensioning process is required to route all these demands independently layer by layer from top to bottom.
Step 2: Routing Client Layer Demands
For each demand in a client layer, Dijkstras routing algorithm is applied to find the shortest path based on the topology in the bottom transmission layer. Depending on the protection type, a second protection path may also be found for each demand. In addition, demand splitting may be supported. As a result, the routing process will generate a set of routes, through which the traffic demands are routed.
Step 3: Bundling
After all traffic demands on a low-rate client layer are routed, they may be bundled in a server layer. For a bundling process, a client layer and a server layer that are related to the bundling process should be designated first. There are three types of bundling strategies, including (1) end-to-end bundling, (2) link-by-link bundling, and (3) bundling reoptimization.
End-to-end bundling
The end-to-end bundling strategy is simple enough to multiplex low-rate tributaries in the client layer into high-rate capacity trunks in the server layer in an end-to-end fashion. The bundling process will generate an intermediate demand matrix for the server layer. For example, if seven units of tributaries in the OC-1 layer are bundled onto the OC-3 layer, the bundling process will generate three units of OC-3 tributaries in the OC-3 layer, which is a demand in the OC-3 layer.
Link-by-link bundling
In contrast to end-to-end bundling, link-by-link bundling bundles traffic demand on a physical-topology-link or server-layer-topology-link basis. That is, all the traffic demands are routed based on the physical topology first, and then all the demands on a physical link or server-layer link are bundled. For example, if there are seven units of OC-1 routed over a common physical link, then on the serve layer (e.g., OC-3 layer) three units of OC-3 need to be established between the two end nodes of the server link.
Bundling Re-optimization
After bundling, a re-optimization process can be carried out to decrease the number of bundling links in the server layer. The purpose of the re-optimization is to clear traffic on some server links that have few traffic demands, by rerouting these demands onto other server links. If all the traffic demands are successfully re-routed, these server links can be removed from the design, as they are carrying no traffic demands. Different re-optimization strategies can be applied respectively for end-to-end and link-by-link bundling.
Step 4: Integrate Demand Matrices on an Intermediate Server Layer
From a bundling process, an intermediate server layer can have internal demand matrices generated from upper-layer traffic demands. Also, each network layer can have its own native demand matrix, which composes demands of customers who require network capacity in tributary of the current layer. These two types of demand matrices have the same level of tributary and make up a total demand matrix in the intermediate server layer. Thus, the integration of these two types of demand matrix will generate a total demand matrix for the current intermediate layer. This new demand matrix will be used for the following routing and bundling steps.
Step 5: Route Integrated Demand Matrix and Bundling
An intermediate server can also be a client layer of another lower server layer. The previous obtained integrated traffic demand matrix should also be routed in the physical layer and bundled on the next server layer. Again, Dijkstras algorithm can be used to route the integrated demand matrix. Accordingly, a bundling and bundling re-optimization process can be performed to bundle the integrated traffic demands on the next server layer. The server layer is the current intermediate server layer. A similar demand matrix integration process can be further carried out to sum up an intermediate internal demand matrix and a native external demand matrix to form an integrated demand matrix for the current intermediate server layer. In summary, the above routing, bundling, and integration steps will be carried out recursively until the transmission layer. To that end, the dimensioning process is completed.
Step 6: Cost Evaluation, Equipment List, and Performance Analysis
Based on the previous network dimensioning, we can eventually make a total cost evaluation, list out all the equipment requirement and configuration, and make what-if analyses for the new design such as reliability and availability analyses.
Nokia N93i - A Special Gift From Nokia
The Nokia N93i is a amazingly exotic mobile phone with all the works of a real digital camcorder. This 3G technology based phone with a folding mechanism runs on a Symbian operating system with S60 3.0 software. The biggest strength of the phone is its 3.2 megapixel camera with a Carl Zeiss lens, 3 x optical zoom, 20 x digital zoom, and autofocus. The phone has a powerful video recorder with 3 x optical zoom and 8 x digital zoom, which provides the perfect reason for mobile users to exercise their film making skills. The phone also features a secondary camera for users to make video calls. This Tri Band phone has a media player and a real player for optimum musical experience in various music formats. Connectivity tools on the Nokia N93i like 3G, Bluetooth, USB 2.0, pop port, infra red, and WLAN allow users to enjoy a high speed data sharing experience with other compatible devices. The phone also incorporates XHTML and HTML browsers for an easier access to the world of Internet.
Leading mobile phone manufacturer Nokia has set the trail ablaze with some of their revolutionary phones, and the Nokia N93i is their specialist in the camera phone genre. The Nokia N93i is a 3G phone with a Symbian S60 3.0 software based operating system that boasts of a 3.2 megapixel camera enumerating 3 x optical zoom, 20 x digital zoom, Carl Zeiss lens, and autofocus. The video recorder of the phone has a 3 x optical zoom and 8 x digital zoom with smart features like scene settings and Adobe Premiere Elements 3.0 to display DVD quality videos on its TFT colour screen. The screen of this clamshell phone can be swivelled to the user's desired angle. This Tri Band phone incorporates connectivity tools like Bluetooth, USB 2.0, Pop Port, infra red, and WLAN along with XHTML and HTML browsers to connect to the Internet. The digital music player of the phone gives out good quality music in MP3 and true tones.
Leading mobile phone manufacturer Nokia has set the trail ablaze with some of their revolutionary phones, and the Nokia N93i is their specialist in the camera phone genre. The Nokia N93i is a 3G phone with a Symbian S60 3.0 software based operating system that boasts of a 3.2 megapixel camera enumerating 3 x optical zoom, 20 x digital zoom, Carl Zeiss lens, and autofocus. The video recorder of the phone has a 3 x optical zoom and 8 x digital zoom with smart features like scene settings and Adobe Premiere Elements 3.0 to display DVD quality videos on its TFT colour screen. The screen of this clamshell phone can be swivelled to the user's desired angle. This Tri Band phone incorporates connectivity tools like Bluetooth, USB 2.0, Pop Port, infra red, and WLAN along with XHTML and HTML browsers to connect to the Internet. The digital music player of the phone gives out good quality music in MP3 and true tones.
Editing HD Video
Working with the video of camcorders such as the Sony
HDR-HC1 can produce a serious business. HD video
contains four times the number of pixels that
standard definition offers, and it's much more
heavily compressed.
Keep in mind that you need a powerful computer with
a lot of memory to deal with the extra data and
compression. Pinnacle for example, recommends a
minimum 512 MB of RAM and a graphics card with 128
MB of RAM for standard resolution video, although
that goes up to a GB of RAM and a 256 MB graphics
card when working with 1080i HD video.
You can find plenty of software available that
supports editing high definition videos. For example,
the latest versions of Pinnacle Studio and Ulead
Media Studio 8 can import and edit files in HDV
format.
Even though the high definition video with these
types of looks great when played back on an HDTV,
at the present time is there is no way store HD
video on a DVD. The only way you can store HD
video for playback is on your PC or the same type
of media you used in your HD camcorder.
There is however, a new generation of high definition
optical media format coming soon. Products that
are based on the HD-DVD and Blu-ray disc formats
are very expensive, and they will remain that way
for the near future.
HD-DVD players were announced a while back that
they will cost $500 and up, and will be available
very soon. You'll also need one of the new HD-DVD
drives to write to the disc, which will cost as
much again. You can expect the same story with the
Blu-ray disc, as both the recorders and the players
are going to be expensive for a while to come.
There is one other option as well. There is a
DVD player from KISS, the DP-600, which can play
back high definition files that have been compressed
to Microsoft's Windows Media 9 format. This can
at least provide a stop gap until the price of the
HD-DVD and Blue-ray disc players and writes come
down to an affordable price.
You can always play back the recorded video you
have through the camcorder itself, although you
shouldn't expect to be able to write it out on a
disc with the current available equipment and
preserve its quality. If you wait it out, the new
generation of available media will be everything
you need for your HD video.
More information on HD Video here http://www.hdcamerasworld.com
HDR-HC1 can produce a serious business. HD video
contains four times the number of pixels that
standard definition offers, and it's much more
heavily compressed.
Keep in mind that you need a powerful computer with
a lot of memory to deal with the extra data and
compression. Pinnacle for example, recommends a
minimum 512 MB of RAM and a graphics card with 128
MB of RAM for standard resolution video, although
that goes up to a GB of RAM and a 256 MB graphics
card when working with 1080i HD video.
You can find plenty of software available that
supports editing high definition videos. For example,
the latest versions of Pinnacle Studio and Ulead
Media Studio 8 can import and edit files in HDV
format.
Even though the high definition video with these
types of looks great when played back on an HDTV,
at the present time is there is no way store HD
video on a DVD. The only way you can store HD
video for playback is on your PC or the same type
of media you used in your HD camcorder.
There is however, a new generation of high definition
optical media format coming soon. Products that
are based on the HD-DVD and Blu-ray disc formats
are very expensive, and they will remain that way
for the near future.
HD-DVD players were announced a while back that
they will cost $500 and up, and will be available
very soon. You'll also need one of the new HD-DVD
drives to write to the disc, which will cost as
much again. You can expect the same story with the
Blu-ray disc, as both the recorders and the players
are going to be expensive for a while to come.
There is one other option as well. There is a
DVD player from KISS, the DP-600, which can play
back high definition files that have been compressed
to Microsoft's Windows Media 9 format. This can
at least provide a stop gap until the price of the
HD-DVD and Blue-ray disc players and writes come
down to an affordable price.
You can always play back the recorded video you
have through the camcorder itself, although you
shouldn't expect to be able to write it out on a
disc with the current available equipment and
preserve its quality. If you wait it out, the new
generation of available media will be everything
you need for your HD video.
More information on HD Video here http://www.hdcamerasworld.com
Document Storage Scanning To CD
Fast and easy retrieval of you information is critical to your business success. And your documents, both on hard drive and paper, are the lifeblood of your organization. So it makes sense to preserve them for any eventuality. But should you try to do it yourself of find a professional firm to do it for you? Read on to find out.
Document Storage: Why You Should Outsource
Fast and easy retrieval of you information is critical to your business success. And your documents, both on hard drive and paper, are the lifeblood of your organization. So it makes sense to preserve them for any eventuality.
But whether your documents are on paper or in electronic form, your data can still be at the mercy of natural or man-made disaster or hard-drive failure. Such loss could cripple your business so it's essential to have an effective back-up system in place. So how to do it?
Transferring you paper documents and hard-disk data to optical media is the first step. This allows easy retrieval of any information you need. With an efficient indexing system, just pop the disc into the drive and voila. No need to search through dusty storerooms and cart out heavy boxes.
Once you've decided to go ahead and backup your critical data, you have to decide whether to do it yourself or outsource to a professional company.
It really depends on the volume of documents you have to work with. But considering the importance of your company information, it makes sense to bring in a professional firm for the following reasons.
Firstly, they're up-to-date on the latest and most effective methods of data storage. For example, perhaps you've already backed up some of your hard disk data to standard Cd's. After all, they last forever, right? Unfortunately not. Some statistics on the shelf life of recorded Cd's might shock you. Unless you take great care, standard CD/DVDs can degrade to the point of being unreadable in as little to 2-5 years. Professional data storage firm will be knowledgeable of the latest media such as the latest Kodak Gold discs which offer effective lifespan of 80-300 years.
Another important reason to outsource to a document imaging solution provider is that their staff are trained and knowledgeable experts in data conversion. Scanning workflow, for example, is a complicated undertaking, especially if large volumes of documents and deadlines are involved. This really needs an expert's touch. Solution providers also offer data entry services to key-in important meta data from documents to create a searchable database of your paper.
Then professional firms have the state-of-the-art equipment to handle any kind or size of job. The resulting efficiencies lower production costs which leads to lower costs for you. Buying, installing such hardware yourself and then training you own staff in its use would be prohibitively expensive and time-consuming.
In addition, a solution provider will manage your entire document conversion project. This means there's no need to tie-up any of your own resources in the conversion process. Such projects can be complex, requiring needs assessment, planning and estimating before the actual scanning begins. And the imaging company's staff can work on-site on your own premises so there's no need to your confidential documents to leave the building.
Considering the inestimable value of your documents, you need to entrust your project to a reputable firm. Look for one with a proven track-record of working for blue chip clients which should include vertical market expertise. If you deal with large format documents, make sure the firm employs technicians familiar with architectural or engineering drawings and who can effectively handle such jobs.
New York Document Scanning, a global outsourcing company, is headquartered in New York, NY with offices in Kolkata, India and provides scanning services at some of the best prices found anywhere. Get free quotes for all your document scanningneeds
Document Storage: Why You Should Outsource
Fast and easy retrieval of you information is critical to your business success. And your documents, both on hard drive and paper, are the lifeblood of your organization. So it makes sense to preserve them for any eventuality.
But whether your documents are on paper or in electronic form, your data can still be at the mercy of natural or man-made disaster or hard-drive failure. Such loss could cripple your business so it's essential to have an effective back-up system in place. So how to do it?
Transferring you paper documents and hard-disk data to optical media is the first step. This allows easy retrieval of any information you need. With an efficient indexing system, just pop the disc into the drive and voila. No need to search through dusty storerooms and cart out heavy boxes.
Once you've decided to go ahead and backup your critical data, you have to decide whether to do it yourself or outsource to a professional company.
It really depends on the volume of documents you have to work with. But considering the importance of your company information, it makes sense to bring in a professional firm for the following reasons.
Firstly, they're up-to-date on the latest and most effective methods of data storage. For example, perhaps you've already backed up some of your hard disk data to standard Cd's. After all, they last forever, right? Unfortunately not. Some statistics on the shelf life of recorded Cd's might shock you. Unless you take great care, standard CD/DVDs can degrade to the point of being unreadable in as little to 2-5 years. Professional data storage firm will be knowledgeable of the latest media such as the latest Kodak Gold discs which offer effective lifespan of 80-300 years.
Another important reason to outsource to a document imaging solution provider is that their staff are trained and knowledgeable experts in data conversion. Scanning workflow, for example, is a complicated undertaking, especially if large volumes of documents and deadlines are involved. This really needs an expert's touch. Solution providers also offer data entry services to key-in important meta data from documents to create a searchable database of your paper.
Then professional firms have the state-of-the-art equipment to handle any kind or size of job. The resulting efficiencies lower production costs which leads to lower costs for you. Buying, installing such hardware yourself and then training you own staff in its use would be prohibitively expensive and time-consuming.
In addition, a solution provider will manage your entire document conversion project. This means there's no need to tie-up any of your own resources in the conversion process. Such projects can be complex, requiring needs assessment, planning and estimating before the actual scanning begins. And the imaging company's staff can work on-site on your own premises so there's no need to your confidential documents to leave the building.
Considering the inestimable value of your documents, you need to entrust your project to a reputable firm. Look for one with a proven track-record of working for blue chip clients which should include vertical market expertise. If you deal with large format documents, make sure the firm employs technicians familiar with architectural or engineering drawings and who can effectively handle such jobs.
New York Document Scanning, a global outsourcing company, is headquartered in New York, NY with offices in Kolkata, India and provides scanning services at some of the best prices found anywhere. Get free quotes for all your document scanningneeds
Selecting Your Direct TV Receiver
When a customer receives Direct TV programming, he or she has a number of choice as to what kind of Direct TV receiver that they can use. Many manufacture a variety of Direct TV receivers for consumers to choose from depending on their entertainment needs. Most new customers will receive a Direct TV receiver for free with installation and a new programming agreement. If a customer prefers to upgrade their Direct TV receiver, they can choose from at least five different receivers.
The Direct TV receiver is designed with offering the customer everything that he or she will need in order to have the best experience with their satellite television reception. It is one of the most popular and affordable Direct TV receivers and offers up to 225 channels of digital programming. The Hughes Director Direct TV receiver is most commonly the kind of receiver that is included in a free equipment and free installation offer from Direct TV.
The Direct TV receiver boasts all of the practicality that is presented in the Director receiver with additional features. Some of the features customers might be interested in include progressive picture adjustments, single-touch recording abilities, digital sound technology and a menu that can be customized to fit each individuals needs. Another choice is the DVR powered by TiVo Direct TV receiver that allows a person to immediately replay live television, pause, rewind or even view the program in slow motion. The need for timers and VCRs no longer exist with the sleek design and technology in this particular Direct TV receiver.
The HDTV DVR with TiVo Direct TV receiver provides new or existing customers with high-definition satellite television from Direct TV. Programming is viewed with up to 1080i lines of resolution for high-definition televisions, HDMI and component video output and an optical output for complete Dolby Digital 5.1. If a customer doesnt want to take advantage of a Direct TV receiver with DVR but still wants to get the most out of his or her high-definition television, then the Hughes HDTV Direct TV receiver would make an excellent choice. The Platinum HD provides Dolby Digital sound capabilities and up to 1080i lines of resolution is a wide 16.9 movie format or 4.3 standard format that lets the viewer choose his or her preferred viewing experience
The Direct TV Receiver or IRD (integrated receiver/decoder) is a device used to block/unblock and customize the different kinds of channels that are coming through your parabolic service. Every Direct TV Receiver comes with Locks and Limits (parental control), access card, on-screen guide and can be seen on as many televisions as you like. With any monthly service package you can get up to five Direct TV Receivers.
The Locks & Limits (parental control) is mostly for making sure that you don't spend too much money on Pay Per View in a given month without wanting to. It can however also be used to take control of what people may and may not watch while at home alone. In the case of curious growing children, that can be important. Everyone needs to know limits sometimes.
As the Direct TV Satellite Receiver is a virtual adventure and does the job of translating everything that goes on in the digital universe of a given channel at any one time, this can be quite useful to worried parents.
The access card that comes with every single Direct TV Receiver is in a sense a kind of identification plate just for your system and will offer all the security system and encryption information needed to make the very best use of the channels you do and do not wish to view most. Also, there is a microprocessor contained inside the access card that responds as an acting auxiliary processor for the Direct TV Receiver.
The Direct TV receiver is designed with offering the customer everything that he or she will need in order to have the best experience with their satellite television reception. It is one of the most popular and affordable Direct TV receivers and offers up to 225 channels of digital programming. The Hughes Director Direct TV receiver is most commonly the kind of receiver that is included in a free equipment and free installation offer from Direct TV.
The Direct TV receiver boasts all of the practicality that is presented in the Director receiver with additional features. Some of the features customers might be interested in include progressive picture adjustments, single-touch recording abilities, digital sound technology and a menu that can be customized to fit each individuals needs. Another choice is the DVR powered by TiVo Direct TV receiver that allows a person to immediately replay live television, pause, rewind or even view the program in slow motion. The need for timers and VCRs no longer exist with the sleek design and technology in this particular Direct TV receiver.
The HDTV DVR with TiVo Direct TV receiver provides new or existing customers with high-definition satellite television from Direct TV. Programming is viewed with up to 1080i lines of resolution for high-definition televisions, HDMI and component video output and an optical output for complete Dolby Digital 5.1. If a customer doesnt want to take advantage of a Direct TV receiver with DVR but still wants to get the most out of his or her high-definition television, then the Hughes HDTV Direct TV receiver would make an excellent choice. The Platinum HD provides Dolby Digital sound capabilities and up to 1080i lines of resolution is a wide 16.9 movie format or 4.3 standard format that lets the viewer choose his or her preferred viewing experience
The Direct TV Receiver or IRD (integrated receiver/decoder) is a device used to block/unblock and customize the different kinds of channels that are coming through your parabolic service. Every Direct TV Receiver comes with Locks and Limits (parental control), access card, on-screen guide and can be seen on as many televisions as you like. With any monthly service package you can get up to five Direct TV Receivers.
The Locks & Limits (parental control) is mostly for making sure that you don't spend too much money on Pay Per View in a given month without wanting to. It can however also be used to take control of what people may and may not watch while at home alone. In the case of curious growing children, that can be important. Everyone needs to know limits sometimes.
As the Direct TV Satellite Receiver is a virtual adventure and does the job of translating everything that goes on in the digital universe of a given channel at any one time, this can be quite useful to worried parents.
The access card that comes with every single Direct TV Receiver is in a sense a kind of identification plate just for your system and will offer all the security system and encryption information needed to make the very best use of the channels you do and do not wish to view most. Also, there is a microprocessor contained inside the access card that responds as an acting auxiliary processor for the Direct TV Receiver.
2007年9月27日星期四
Data Recovery: Counteracting Data Loss
With several companies and businesses relying on computers for storing their reports, files, and information sheets, protecting systems is no longer enough to emerge at the top of the industry. Data recovery is the latest in counteracting loss of data whether its due to bad weather, hardware failure, malicious intent, or human failure.
Before, much confusion and inconsistencies in information about data loss made data loss and data recovery the most misunderstood concept in the computer industry. Because of this, many users and experts often consider lost data as permanently damaged with no way of retrieving it. But now, with the advent of new facts on data recovery and loss, computer whiz and experts are now focusing more on restoring data into the systems as a new way of overcoming data loss or corruption.
The discovery of the concept of file retrieval led to several data recovery experts offering their online services. The services offered by these experts range from hard drive recovery, software or program retrieval, mailbox file retrieval, and more. Data recovery services are practically endless with numerous experts coming up with more and more ways of recovering important files and programs that are lost.
So what exactly is data recovery?
Data recovery, according to the word sleuths and recovery experts, is the process of salvaging of deleted or inaccessible data stored on damaged media like magnetic disks and computer hard drives, optical devices, and tape cartridges. A large number of file retrieval software and data recovery service is designed to help users retrieve their files at the event of a computer crash or viral infection.
How does data recovery work?
The first step of the process of data recovery service usually involves evaluation where the initial analysis of the extent of the data lost is determined. After the prognosis, the data recovery experts and technicians would then proceed in cloning or copying the media and queuing it into their systems. The actual file retrieval process occurs when the technicians secure and extract the data from the copy of the damaged media.
Hardware and Software Teams
A damaged media has the data locked within it and it is the job of highly experienced hardware and software engineers to unlock it. These two teams of experts work very closely together throughout the project, combining all their experiences in their respective fields to solve the problem quickly and surely.
For safety measures, hardware engineers access as much of the disk as they can to produce the copy which they then share with the software specialists. The bulk of the file retrieval process lies on the software team as they are the ones who do the actual extraction using complicated software programs designed especially for recovery work. The ensuing data are then filed and written onto a new, undamaged media.
Data recovery has become an essential part of the computer industry. Many companies offering data recovery service invest heavily on research and development to ensure efficiency in the whole spectrum of data recovery.
Before, much confusion and inconsistencies in information about data loss made data loss and data recovery the most misunderstood concept in the computer industry. Because of this, many users and experts often consider lost data as permanently damaged with no way of retrieving it. But now, with the advent of new facts on data recovery and loss, computer whiz and experts are now focusing more on restoring data into the systems as a new way of overcoming data loss or corruption.
The discovery of the concept of file retrieval led to several data recovery experts offering their online services. The services offered by these experts range from hard drive recovery, software or program retrieval, mailbox file retrieval, and more. Data recovery services are practically endless with numerous experts coming up with more and more ways of recovering important files and programs that are lost.
So what exactly is data recovery?
Data recovery, according to the word sleuths and recovery experts, is the process of salvaging of deleted or inaccessible data stored on damaged media like magnetic disks and computer hard drives, optical devices, and tape cartridges. A large number of file retrieval software and data recovery service is designed to help users retrieve their files at the event of a computer crash or viral infection.
How does data recovery work?
The first step of the process of data recovery service usually involves evaluation where the initial analysis of the extent of the data lost is determined. After the prognosis, the data recovery experts and technicians would then proceed in cloning or copying the media and queuing it into their systems. The actual file retrieval process occurs when the technicians secure and extract the data from the copy of the damaged media.
Hardware and Software Teams
A damaged media has the data locked within it and it is the job of highly experienced hardware and software engineers to unlock it. These two teams of experts work very closely together throughout the project, combining all their experiences in their respective fields to solve the problem quickly and surely.
For safety measures, hardware engineers access as much of the disk as they can to produce the copy which they then share with the software specialists. The bulk of the file retrieval process lies on the software team as they are the ones who do the actual extraction using complicated software programs designed especially for recovery work. The ensuing data are then filed and written onto a new, undamaged media.
Data recovery has become an essential part of the computer industry. Many companies offering data recovery service invest heavily on research and development to ensure efficiency in the whole spectrum of data recovery.
Spot Game and Fish With Hunting Binoculars
Sitting in the woods waiting for game to pass by can be a tedious wait, but you can gain an advantage by using hunting binoculars while sitting in your tree stand. You will able to spot the game from a distance and verify a projected path and end the question of which way it is traveling.
However, there are numerous considerations in choosing the best hunting binoculars for you, and the geographical locations in which you hunt. Magnification, light gathering and ability to work in the weather environment of your hunting grounds will determine a good pair of hunting binoculars.
For general use binoculars with a size rating of 8x30 would work well, that is they have a magnification factor of eight and light gathering ability of 30. However, if you plan to get out in the wilds before dawn, perhaps hunting binoculars with a 8x40 or 7x50 rating would be better as they would have more light gathering capability.
Check For Non-Fogging Lenses
Hermetically sealed hunting binoculars filed with nitrogen are generally used for extreme weather conditions where freezing is a distinct possibility. They should also have the ability to be collimated as they may need adjusting as time goes by.
Each side of hunting binoculars are simple a telescope attached to another identical telescope. Their optical array is different than traditional telescopes to make them smaller and easier to handle. Both sides should give a bright, clear and identical image if viewed individually. Working together they give the appearance of a three-dimensional image, nearly identical to the original.
Magnesium fluoride coated lenses also reduce reflection to allow for brighter and more accurate renditions of the subject. A good pair of hunting binoculars will also have reduced reflective quality to reduce the amount of glare visible to animals. The outside of the unit should also be considered as to its visibility to game animals. Camouflage coverings are popular on hunting binoculars.
Another concern of hunters is noise and hunting binoculars usually have no exposed metal which would click together and possibly give away a hunter's position. Putting it all together you might consider a 12x50 power set of hunting binoculars with coated lenses, ability to be calibrated and collimated as they get used. Flat green exterior with rubberized coating, nitrogen-filled and waterproof for up to one meter depth, providing years of reliable service and weighing just under two pounds.
Fishing Binoculars Help Imaging On Water
Due to light refraction through water, seeing undistorted images is a problem but a good pair of fishing binoculars can make the images more colorful, more realistic and without the distortion. Ultraviolet coating on the lenses of fishing binoculars also reduces the glare from the sun as it hits the water.
If you are on the water looking for signs of where the big fish are located, such as jumping Marlin or Blue Fish, a good pair of fishing binoculars can be a big help. The distortion-free vision offered on many models gives a better idea of the distance and most fishing binoculars come with extreme depth of field capabilities allowing for sharp images anywhere from 20 yards to infinity.
Fishing binoculars, since used on or near the water, are generally waterproof and the depth of their resistance to water infiltration will often determine the price. It is also important to remember to protect your fishing binoculars from the continued exposure to salt water if they are used on ocean cruises.
Seek Out Features You Need
If you are planning to spend a lot of time on a boat then fishing binoculars with coated lenses is necessary. These will reduce the amount of glare from the sun and make your images more defined. Additionally, with the glare almost completely gone, images will not be hidden by the reflected light.
Whether you are using the fishing binoculars to actually look for fish movement on the water or for trying to spot the shoreline if you get lost, be sure the magnification is strong enough to meet your needs. Depending on the size of the water way you be on will determine the strength of the fishing binoculars you will need.
Center focus fishing binoculars will enable one-handed operation easier and along with the prism being mounted on the roof of the binoculars making them more compact, they will be easier to carry, store and use. A rough waterproof coating is also desirable to make for more sure handling if they, or your hands, do get wet so they will not slip overboard.
The angle of view is determined by the lens size and depending on your needs, you may want a wider view lens. Similar to the lens on a camera, fishing binoculars also come with a variety of lenses. They are available from numerous manufacturers in many styles and magnifications. Resultantly, costs can range from about $40 to several thousands of dollars.
However, there are numerous considerations in choosing the best hunting binoculars for you, and the geographical locations in which you hunt. Magnification, light gathering and ability to work in the weather environment of your hunting grounds will determine a good pair of hunting binoculars.
For general use binoculars with a size rating of 8x30 would work well, that is they have a magnification factor of eight and light gathering ability of 30. However, if you plan to get out in the wilds before dawn, perhaps hunting binoculars with a 8x40 or 7x50 rating would be better as they would have more light gathering capability.
Check For Non-Fogging Lenses
Hermetically sealed hunting binoculars filed with nitrogen are generally used for extreme weather conditions where freezing is a distinct possibility. They should also have the ability to be collimated as they may need adjusting as time goes by.
Each side of hunting binoculars are simple a telescope attached to another identical telescope. Their optical array is different than traditional telescopes to make them smaller and easier to handle. Both sides should give a bright, clear and identical image if viewed individually. Working together they give the appearance of a three-dimensional image, nearly identical to the original.
Magnesium fluoride coated lenses also reduce reflection to allow for brighter and more accurate renditions of the subject. A good pair of hunting binoculars will also have reduced reflective quality to reduce the amount of glare visible to animals. The outside of the unit should also be considered as to its visibility to game animals. Camouflage coverings are popular on hunting binoculars.
Another concern of hunters is noise and hunting binoculars usually have no exposed metal which would click together and possibly give away a hunter's position. Putting it all together you might consider a 12x50 power set of hunting binoculars with coated lenses, ability to be calibrated and collimated as they get used. Flat green exterior with rubberized coating, nitrogen-filled and waterproof for up to one meter depth, providing years of reliable service and weighing just under two pounds.
Fishing Binoculars Help Imaging On Water
Due to light refraction through water, seeing undistorted images is a problem but a good pair of fishing binoculars can make the images more colorful, more realistic and without the distortion. Ultraviolet coating on the lenses of fishing binoculars also reduces the glare from the sun as it hits the water.
If you are on the water looking for signs of where the big fish are located, such as jumping Marlin or Blue Fish, a good pair of fishing binoculars can be a big help. The distortion-free vision offered on many models gives a better idea of the distance and most fishing binoculars come with extreme depth of field capabilities allowing for sharp images anywhere from 20 yards to infinity.
Fishing binoculars, since used on or near the water, are generally waterproof and the depth of their resistance to water infiltration will often determine the price. It is also important to remember to protect your fishing binoculars from the continued exposure to salt water if they are used on ocean cruises.
Seek Out Features You Need
If you are planning to spend a lot of time on a boat then fishing binoculars with coated lenses is necessary. These will reduce the amount of glare from the sun and make your images more defined. Additionally, with the glare almost completely gone, images will not be hidden by the reflected light.
Whether you are using the fishing binoculars to actually look for fish movement on the water or for trying to spot the shoreline if you get lost, be sure the magnification is strong enough to meet your needs. Depending on the size of the water way you be on will determine the strength of the fishing binoculars you will need.
Center focus fishing binoculars will enable one-handed operation easier and along with the prism being mounted on the roof of the binoculars making them more compact, they will be easier to carry, store and use. A rough waterproof coating is also desirable to make for more sure handling if they, or your hands, do get wet so they will not slip overboard.
The angle of view is determined by the lens size and depending on your needs, you may want a wider view lens. Similar to the lens on a camera, fishing binoculars also come with a variety of lenses. They are available from numerous manufacturers in many styles and magnifications. Resultantly, costs can range from about $40 to several thousands of dollars.
7 Things You Should Know About Optical Migraines
Sometime in our lives, we experience headaches that come and go and are often so severe that our daily routines are affected. Oftentimes, when these headaches occur, we also experience some form of visual changes. Then we say, Its probably just a migraine.
1. What is a migraine?
Migraine is a recurrent type of headache that is severely painful and usually occurs only on one side of the head. An aura occurs right before one of these attacks. An aura could be manifested as visual flashes or spots or even ringing in the ears which is opposite of the side where the headache is about to occur. The migraine attack may also come with symptoms of dizziness, vomiting, nausea and double vision.
2. What is an optical migraine?
As opposed to a real migraine, an optical migraine also involves an aura that comes before a migraine attack, but there is the absence of pain. This is rarer than the migraine that comes with severe pain. It is also know as acephalgic migraine or visual or ocular migraine. It is a migraine aura unaccompanied by headache.
The visual disturbances that are experienced are flashing lights that look like zigzag or fortress-like lights. These auras usually begin as small visual marches crossing the field of vision that slowly fades away. Attacks like these last for several minutes to almost an hour.
If it will come with a headache, the pain will follow in an hour. An optical migraine can also be experienced as a blind spot in the field of vision.
3. How sure am I that I am experiencing an optical migraine?
Migraines are usually diagnosed if the same symptoms are experiences over and over in many years. It is optical migraine if the same aura is experienced. In case there is a change in the visual pattern, it might be something more serious. A doctor should be consulted in this case.
4. What could be the cause of these migraines?
The cause for migraine is not yet confirmed, it has remained unknown. However, there have been theories that these headaches are caused by allergies, temporary edema of the brain and even endocrine disturbances. One thing is for sure, it is due to disturbance in the blood circulation in the brain. It has been proven that the pain is associated with the narrowing of blood vessels in the brain followed by dilation.
5. What could be more serious causes of headaches if they are not migraines?
Not all headaches are migraines and not all visual disturbances are caused by migraines. There could be more serious causes that may force you to consult a doctor. Visual changes can also be caused by partial seizures, a retina in the eye could have been detached, a mini-stroke or a transient ischemic attack, multiple sclerosis or even a brain tumor.
6. Who is more likely to get an optical migraine?
Optical migraines are usually experienced by more women than men at a ratio of 3:1. This is an illness that is usually inherited.
7. What is the common treatment for optical migraines?
Sedatives and aspirin are common medications prescribed to patients with this illness. Resting or sleeping in a dark room usually relieves the symptoms. However, if the aural migraine is accompanied by severe headache, injection of triptans or ingestion or nasal spraying of the same drug gives relief. Beta-blockers, antidepressants and antiepileptic drugs are also effective for most patients.
It is important to recognize the aura that comes before the headache so that medication can be taken before the actual attack. This will prevent the pain from setting in. Biofeedback has been proven to be a good type of therapy for patients who get these attacks.
Having all these in mind, you would now know if you are experiencing an ordinary headache or a true-blue migraine. Now, you could also determine if those weird visual disturbances are auras previous to a migraine attack or if it is an optical migraine.
What is important here is for you to recognize the symptoms that go with the headache. Observation is the key. You must recognize the tell-tale sign that you are about to get a full-blown attack of a migraine or if you should seek medical help because it is a sign of something more serious. Never take these headaches for granted, they could mean your life.
1. What is a migraine?
Migraine is a recurrent type of headache that is severely painful and usually occurs only on one side of the head. An aura occurs right before one of these attacks. An aura could be manifested as visual flashes or spots or even ringing in the ears which is opposite of the side where the headache is about to occur. The migraine attack may also come with symptoms of dizziness, vomiting, nausea and double vision.
2. What is an optical migraine?
As opposed to a real migraine, an optical migraine also involves an aura that comes before a migraine attack, but there is the absence of pain. This is rarer than the migraine that comes with severe pain. It is also know as acephalgic migraine or visual or ocular migraine. It is a migraine aura unaccompanied by headache.
The visual disturbances that are experienced are flashing lights that look like zigzag or fortress-like lights. These auras usually begin as small visual marches crossing the field of vision that slowly fades away. Attacks like these last for several minutes to almost an hour.
If it will come with a headache, the pain will follow in an hour. An optical migraine can also be experienced as a blind spot in the field of vision.
3. How sure am I that I am experiencing an optical migraine?
Migraines are usually diagnosed if the same symptoms are experiences over and over in many years. It is optical migraine if the same aura is experienced. In case there is a change in the visual pattern, it might be something more serious. A doctor should be consulted in this case.
4. What could be the cause of these migraines?
The cause for migraine is not yet confirmed, it has remained unknown. However, there have been theories that these headaches are caused by allergies, temporary edema of the brain and even endocrine disturbances. One thing is for sure, it is due to disturbance in the blood circulation in the brain. It has been proven that the pain is associated with the narrowing of blood vessels in the brain followed by dilation.
5. What could be more serious causes of headaches if they are not migraines?
Not all headaches are migraines and not all visual disturbances are caused by migraines. There could be more serious causes that may force you to consult a doctor. Visual changes can also be caused by partial seizures, a retina in the eye could have been detached, a mini-stroke or a transient ischemic attack, multiple sclerosis or even a brain tumor.
6. Who is more likely to get an optical migraine?
Optical migraines are usually experienced by more women than men at a ratio of 3:1. This is an illness that is usually inherited.
7. What is the common treatment for optical migraines?
Sedatives and aspirin are common medications prescribed to patients with this illness. Resting or sleeping in a dark room usually relieves the symptoms. However, if the aural migraine is accompanied by severe headache, injection of triptans or ingestion or nasal spraying of the same drug gives relief. Beta-blockers, antidepressants and antiepileptic drugs are also effective for most patients.
It is important to recognize the aura that comes before the headache so that medication can be taken before the actual attack. This will prevent the pain from setting in. Biofeedback has been proven to be a good type of therapy for patients who get these attacks.
Having all these in mind, you would now know if you are experiencing an ordinary headache or a true-blue migraine. Now, you could also determine if those weird visual disturbances are auras previous to a migraine attack or if it is an optical migraine.
What is important here is for you to recognize the symptoms that go with the headache. Observation is the key. You must recognize the tell-tale sign that you are about to get a full-blown attack of a migraine or if you should seek medical help because it is a sign of something more serious. Never take these headaches for granted, they could mean your life.
The Basic Features Of A Spectrum Analyzer
A spectrum analyzer is a device that measures the power spectrum. It is often used to examine the components of a waveform, whether it is electrical, acoustic or optical in form. There are basically two kinds of spectrum analyzers, the analog and the digital.
It also displays the received signal and compares the bandwidth to the frequency. A comparison is often done with an Oscilloscope, which compares the strength of the signal against the time.
Spectrum analyzers are also useful in analyzing amplitude against the frequency. Amplitude is normally measured in power or in dBm instead of volts, which is what is normally used in most spectrum analyzer.
The reason behind this is the fact that there are low signal strengths and frequency of movements that may not be measured. Spectrum Analyzers can only measure the frequency of the response at powers as low as 100 dBm. These are the levels that are frequently seen in microwave receivers. Oscilloscopes, on the other hand, cannot measure such very low voltage. The device can only deal with very low frequency levels and high amplitude.
The analog analyzer uses a filter with a mid-frequency that can be automatically shifted through a series of frequencies where the spectrum will be measured. The digital spectrum, on the other hand, utilizes a mathematical process called the Fast Fourier Transform (FFT), which is used to transform a wavform into the different components of its frequency spectrum. This way, computer programs who do the transformations will make the audio processing much easier. FFTs, however, are not only used for this purpose. They also have applications in other fields.
There are also spectrum analyzers that makes use of a technique wherein the incoming signal is converted into a lower frequency. This hybrid technique uses first the superheterodyne and then the FFT techniques. Examples of spectrum analyzers with this technique are those made by the Tektronix from the real-time spectrum analyzer series.
Spectrum Analyzers have so many applications. One application is the device frequency response measurement, which refers to the amplitude response of a machine against frequency of device.
Another application is Microwave Tower Monitoring, which measures the transmitted power of the machine as well as the power that it receives. This is utilized for the verification if the signal strengths and frequency of the transmitter. A directional coupler is used to tap the power. This is done so as not to disturb or interrupt communications.
A spectrum analyzer is one instrument that is often used in the conversion of higher frequencies, often those that range up to 10s gigahertz. It is a sensitive receiver that works based on the super-heterodyne receiver principles.
Once received by the spectrum analyzer, the frequency signal is swept through a pre-selected set of frequencies. The selected frequency is then converted into a DC level, a logarithmic scale, that can be measured. It is also displayed on the CRT, where the y-axis contains the signal strength while the frequency is seen on the x-axis.
Spectrum analyzers, however, cannot detect signals that are too weak or weaker than the noise in the background. This is the reason why the spectrum analyzer is often used in tandem with an RBW. In fact, RBW is one of the vital considerations in choosing or buying a spectrum analyzer.
Here, the received signal strength is measured in dBm or what is called decibels, the zero of which corresponds to 1mWatt on the logarithm scale. The reason for the use of power or decibels instead of the usual voltage is the fact that what is being measured are the low signal strengths and the frequency range of measurement.
Spectrum analyzers can only measure the response of a device powered at 120 dBm. These are the power levels that are normally seen in microwave receivers.In addition to the RBW, there are other key features of spectrum analyzers that people need to consider before buying one. One of these vital components is the resolution width, which affects the sensitivity of the spectrum analyzer. In fact, the sensitivity is directly dependent on this feature. For instance, if the measurements are the over a wide band, a 3 KHz RBW will normally be effective.
However, if you need to analyze a much narrower spectrum, such as with filters, then you may need a bandwidth resolution of 300Hz or a 10 Hz RBW. All depends on how the spectrum analyzer will be used. Another feature is the frequency range, which refers to the frequencies that you will be needing in order to take measurements. Spectrum analyzers have ranges from 100 Hz to 50.
Another is the frequency stability, which allows the spectrum to maintain its frequency within a specific levels that is precise and accurate. Often, the frequency stability is entirely dependent on the stability of the oscillator. A provision for Narrow band measurements for instance is an important parameter because spectrum analyzers do not usually have very high stability clocks.
It also displays the received signal and compares the bandwidth to the frequency. A comparison is often done with an Oscilloscope, which compares the strength of the signal against the time.
Spectrum analyzers are also useful in analyzing amplitude against the frequency. Amplitude is normally measured in power or in dBm instead of volts, which is what is normally used in most spectrum analyzer.
The reason behind this is the fact that there are low signal strengths and frequency of movements that may not be measured. Spectrum Analyzers can only measure the frequency of the response at powers as low as 100 dBm. These are the levels that are frequently seen in microwave receivers. Oscilloscopes, on the other hand, cannot measure such very low voltage. The device can only deal with very low frequency levels and high amplitude.
The analog analyzer uses a filter with a mid-frequency that can be automatically shifted through a series of frequencies where the spectrum will be measured. The digital spectrum, on the other hand, utilizes a mathematical process called the Fast Fourier Transform (FFT), which is used to transform a wavform into the different components of its frequency spectrum. This way, computer programs who do the transformations will make the audio processing much easier. FFTs, however, are not only used for this purpose. They also have applications in other fields.
There are also spectrum analyzers that makes use of a technique wherein the incoming signal is converted into a lower frequency. This hybrid technique uses first the superheterodyne and then the FFT techniques. Examples of spectrum analyzers with this technique are those made by the Tektronix from the real-time spectrum analyzer series.
Spectrum Analyzers have so many applications. One application is the device frequency response measurement, which refers to the amplitude response of a machine against frequency of device.
Another application is Microwave Tower Monitoring, which measures the transmitted power of the machine as well as the power that it receives. This is utilized for the verification if the signal strengths and frequency of the transmitter. A directional coupler is used to tap the power. This is done so as not to disturb or interrupt communications.
A spectrum analyzer is one instrument that is often used in the conversion of higher frequencies, often those that range up to 10s gigahertz. It is a sensitive receiver that works based on the super-heterodyne receiver principles.
Once received by the spectrum analyzer, the frequency signal is swept through a pre-selected set of frequencies. The selected frequency is then converted into a DC level, a logarithmic scale, that can be measured. It is also displayed on the CRT, where the y-axis contains the signal strength while the frequency is seen on the x-axis.
Spectrum analyzers, however, cannot detect signals that are too weak or weaker than the noise in the background. This is the reason why the spectrum analyzer is often used in tandem with an RBW. In fact, RBW is one of the vital considerations in choosing or buying a spectrum analyzer.
Here, the received signal strength is measured in dBm or what is called decibels, the zero of which corresponds to 1mWatt on the logarithm scale. The reason for the use of power or decibels instead of the usual voltage is the fact that what is being measured are the low signal strengths and the frequency range of measurement.
Spectrum analyzers can only measure the response of a device powered at 120 dBm. These are the power levels that are normally seen in microwave receivers.In addition to the RBW, there are other key features of spectrum analyzers that people need to consider before buying one. One of these vital components is the resolution width, which affects the sensitivity of the spectrum analyzer. In fact, the sensitivity is directly dependent on this feature. For instance, if the measurements are the over a wide band, a 3 KHz RBW will normally be effective.
However, if you need to analyze a much narrower spectrum, such as with filters, then you may need a bandwidth resolution of 300Hz or a 10 Hz RBW. All depends on how the spectrum analyzer will be used. Another feature is the frequency range, which refers to the frequencies that you will be needing in order to take measurements. Spectrum analyzers have ranges from 100 Hz to 50.
Another is the frequency stability, which allows the spectrum to maintain its frequency within a specific levels that is precise and accurate. Often, the frequency stability is entirely dependent on the stability of the oscillator. A provision for Narrow band measurements for instance is an important parameter because spectrum analyzers do not usually have very high stability clocks.
Nintendo Wii Hardware Specs In Easy To Understand Language
Designed to match the PlayStation 3 and the Xbox 360, two of the giants in the video game industry, the Nintendo Wii was designed with state of the art hardware.
It is known in the first place for its revolutionary design and wonderful features that are highly capable of lifting your video game experience to a much higher level.
But, what basically makes the Wii so powerful lies on what is built on its hardware. It is for this reason basically that in almost every site designed for Nintendo, Nintendo Wii hardware specs are often highlighted.
The Nintendo Wii hardware specs generally include precise details about the Nintendo Wii hardware. If you are the type who wants to know everything technical, then consider the following:
The Wii hardware specs often highlight information about its loading slot. Well, this part is placed in the front of the unit and is capable of receiving 12 centimeters of optical discs, as well as 8 centimeters of discs from the older consoled of the Nintendo itself.
Speaking of console, the Wii video game console features two USB ports, and a single SC card slot. There are also some Wii consoles that highlight a number of DVD-Video capabilities. This feature is common for the Wiis released in Japan and the units which will be released early in 2007.
Going beyond the console, most of the Nintendo Wii hardware specs often feature what's inside the Wii remote. Accordingly, the remote is designed with accelerometers, as well as an infrared detection that works significantly to allow the remote to work even in a three dimensional space.
What this means basically is that the Nintendo Wii remote allows the gamers to play the games even with the use of certain hand gestures as well as with the use of the remote buttons. But for this to work functionally, the remote of the Wii must be attached with the console through Bluetooth technology.
Much to that, the Wii sensor bar features are often included in the Nintendo Wii hardware specs. It is described as a tool positioned in a way the Wii remote is designed. The sensor bar can be used as a pointing device which functions even at the distance of about five meters. It is important to note, however, that the sensor bar of the Nintendo Wii is sensitive to sunlight and halogen lights, and once it captures the light, its functions vary.
The other information included in the Nintendo Wii hardware specs are the units 512 MB built-in flash memory, the controller's four slots, and the Wii CPU which boasts a processor named as Broadway.
Note that all of those above mentioned details included in the Nintendo Wii hardware specs are highly capable of making your video game experience ultimate.
It is known in the first place for its revolutionary design and wonderful features that are highly capable of lifting your video game experience to a much higher level.
But, what basically makes the Wii so powerful lies on what is built on its hardware. It is for this reason basically that in almost every site designed for Nintendo, Nintendo Wii hardware specs are often highlighted.
The Nintendo Wii hardware specs generally include precise details about the Nintendo Wii hardware. If you are the type who wants to know everything technical, then consider the following:
The Wii hardware specs often highlight information about its loading slot. Well, this part is placed in the front of the unit and is capable of receiving 12 centimeters of optical discs, as well as 8 centimeters of discs from the older consoled of the Nintendo itself.
Speaking of console, the Wii video game console features two USB ports, and a single SC card slot. There are also some Wii consoles that highlight a number of DVD-Video capabilities. This feature is common for the Wiis released in Japan and the units which will be released early in 2007.
Going beyond the console, most of the Nintendo Wii hardware specs often feature what's inside the Wii remote. Accordingly, the remote is designed with accelerometers, as well as an infrared detection that works significantly to allow the remote to work even in a three dimensional space.
What this means basically is that the Nintendo Wii remote allows the gamers to play the games even with the use of certain hand gestures as well as with the use of the remote buttons. But for this to work functionally, the remote of the Wii must be attached with the console through Bluetooth technology.
Much to that, the Wii sensor bar features are often included in the Nintendo Wii hardware specs. It is described as a tool positioned in a way the Wii remote is designed. The sensor bar can be used as a pointing device which functions even at the distance of about five meters. It is important to note, however, that the sensor bar of the Nintendo Wii is sensitive to sunlight and halogen lights, and once it captures the light, its functions vary.
The other information included in the Nintendo Wii hardware specs are the units 512 MB built-in flash memory, the controller's four slots, and the Wii CPU which boasts a processor named as Broadway.
Note that all of those above mentioned details included in the Nintendo Wii hardware specs are highly capable of making your video game experience ultimate.
Ireland-The Land of Saints and Scholars?
Ireland-The Land of Saints and Scholars?
Ireland is known as The Emerald Isle or The Land of Saints and Scholars. In truth it is one of the world's fastest growing economies where time no longer stands still. It is a country with a young vibrant and energetic population eager to be part of the Celtic Tiger as the rapidly growing economy has become known as.
Ireland is divided into 32 counties and 4 provinces-Munster, Ulster, Connaught and Leinster. The country has a population in excess of 5 million inhabitants. Ireland is famed the world over for its music, literature and friendly folk. U2, Yeats, Beckett and Joyce being just some of the more recognisable names.
Ireland boasts a unique culture one that is truly it's own. While English is the most widely spoken language Gaelic or Irish was the only language spoken until the early 20th century. Gaelic is a fascinating and deeply meaningful language and is still taught widely in all schools today. It is reputed to be one of the hardest three languages in the world to master. Gaelic games such as football and hurling are widely played in Ireland and are a true spectacle to watch. Hurling, played with 15 men on each team and with sticks is the fastest field game in the world. Both games retain amateur status to this day.
Dublin is the capital city and is located in the East of the country on The River Liffey. With a population in excess of 1.25 million Dublin is a lively city with lots to do and see. Home to the famous Guinness beer, Dublin has acquired an International reputation as a great party city. The main landmarks are Grafton Street which is the principle shopping street, O Connell Street-the cities main street and Temple Bar. Temple Bar is the bohemian part of the city full of lively bars, restaurants, nightclubs and art galleries.
Ireland is a real gem and a must see destination for any avid traveller. For those interested in exploring the mystical Isle of Ireland reserving accommodation in advance is always advisable. Car rental should also be booked well in advance and provides a great way to travel at your leisure. Remember that driving in Ireland is on the left hand side of the road! For more information on all aspects of Ireland including booking over 9000 properties and car rental check out the Irish Accommodation Guide.
Ireland is known as The Emerald Isle or The Land of Saints and Scholars. In truth it is one of the world's fastest growing economies where time no longer stands still. It is a country with a young vibrant and energetic population eager to be part of the Celtic Tiger as the rapidly growing economy has become known as.
Ireland is divided into 32 counties and 4 provinces-Munster, Ulster, Connaught and Leinster. The country has a population in excess of 5 million inhabitants. Ireland is famed the world over for its music, literature and friendly folk. U2, Yeats, Beckett and Joyce being just some of the more recognisable names.
Ireland boasts a unique culture one that is truly it's own. While English is the most widely spoken language Gaelic or Irish was the only language spoken until the early 20th century. Gaelic is a fascinating and deeply meaningful language and is still taught widely in all schools today. It is reputed to be one of the hardest three languages in the world to master. Gaelic games such as football and hurling are widely played in Ireland and are a true spectacle to watch. Hurling, played with 15 men on each team and with sticks is the fastest field game in the world. Both games retain amateur status to this day.
Dublin is the capital city and is located in the East of the country on The River Liffey. With a population in excess of 1.25 million Dublin is a lively city with lots to do and see. Home to the famous Guinness beer, Dublin has acquired an International reputation as a great party city. The main landmarks are Grafton Street which is the principle shopping street, O Connell Street-the cities main street and Temple Bar. Temple Bar is the bohemian part of the city full of lively bars, restaurants, nightclubs and art galleries.
Ireland is a real gem and a must see destination for any avid traveller. For those interested in exploring the mystical Isle of Ireland reserving accommodation in advance is always advisable. Car rental should also be booked well in advance and provides a great way to travel at your leisure. Remember that driving in Ireland is on the left hand side of the road! For more information on all aspects of Ireland including booking over 9000 properties and car rental check out the Irish Accommodation Guide.
IR400 series radiometric imaging system
IR400 series radiometric imaging system is very well known as the work house of industry. It is robust images provide the images so real that we start to feel like we were there. It provides us with real time thermal video, accurate temperature measurement, on board color palette and digital image storage. You can always ask for the demo or pre-owned model in stock. The devices are always characterized by:
High accuracy temperature measurement
Thermoelectric cooling for instant start-up
The Workhorse of the Infrared Industry
Rugged design
This device can be used in many was and is applicable in many conditions and industries. It is very easy to use and high sensitivity as more important is portable. This device is built and designed to operate in demanding environment such as off shore applications and steel works. It is water and shock resistance bump and vibration protected and can also be operated even in areas where electro magnetic fields are present. This device is one of the best designed thermal infrared imaging radio meters available.
The device offers you
1. Crisp color thermal imaging
2. Highly accurate temperature measurement
3. Onboard floppy disk image storage
4. Internal magnification (zoom) features
5. Industrial Shock and vibration housing
6. Integrated Macro Focus
7. A wide selection of optical solutions
The macro focus is always shown in the images by using this mode you can focus in on an area 13mm * 13mm and fill the frame with thermal imagery. The target is the size of finger nail. This feature is not available in any other thermal imaging camera. This device is also applicable in medical applications such as blood flow / vascular studies, inflammation location and other thermal medical applications. Low in cost and portable thermal imaging camera to carry out what ever you want, the most suitable device is the IR400 series radiometric. Proven that it is best from the monitoring market, and voted to be most accurate and reliable.
With wavelength 2-5 Um (shortwave), detector type MCT Sprite, and Thermal Sensitivity is 0.1 c. the warm up time is less than 5 seconds, Image Storage is 3.5" floppy, and SWIR Gm 20 degree FOV lens are used as the optics. Focus range is 12" to infinity and Integrated Macro Focus is 13mm X 13mm area fills the frame. Video out is Standard RCA RS-170 and External screen is Color, high resolution TFT active matrix.
Author- 7bInfrared Products The company is into thermal Infrared products and night vision equipment like night vision goggle, night vision binocular.infrared camera.
High accuracy temperature measurement
Thermoelectric cooling for instant start-up
The Workhorse of the Infrared Industry
Rugged design
This device can be used in many was and is applicable in many conditions and industries. It is very easy to use and high sensitivity as more important is portable. This device is built and designed to operate in demanding environment such as off shore applications and steel works. It is water and shock resistance bump and vibration protected and can also be operated even in areas where electro magnetic fields are present. This device is one of the best designed thermal infrared imaging radio meters available.
The device offers you
1. Crisp color thermal imaging
2. Highly accurate temperature measurement
3. Onboard floppy disk image storage
4. Internal magnification (zoom) features
5. Industrial Shock and vibration housing
6. Integrated Macro Focus
7. A wide selection of optical solutions
The macro focus is always shown in the images by using this mode you can focus in on an area 13mm * 13mm and fill the frame with thermal imagery. The target is the size of finger nail. This feature is not available in any other thermal imaging camera. This device is also applicable in medical applications such as blood flow / vascular studies, inflammation location and other thermal medical applications. Low in cost and portable thermal imaging camera to carry out what ever you want, the most suitable device is the IR400 series radiometric. Proven that it is best from the monitoring market, and voted to be most accurate and reliable.
With wavelength 2-5 Um (shortwave), detector type MCT Sprite, and Thermal Sensitivity is 0.1 c. the warm up time is less than 5 seconds, Image Storage is 3.5" floppy, and SWIR Gm 20 degree FOV lens are used as the optics. Focus range is 12" to infinity and Integrated Macro Focus is 13mm X 13mm area fills the frame. Video out is Standard RCA RS-170 and External screen is Color, high resolution TFT active matrix.
Author- 7bInfrared Products The company is into thermal Infrared products and night vision equipment like night vision goggle, night vision binocular.infrared camera.
Tips for buying your digital camera
So you have decided to get a new digital camera? or maybe it is your first one? Like many other consumer electronic devices digital cameras change all the time. For the same amount of money you can get more and more features: mega pixels, storage space, zoom and more. In this article we will give you a few practical tips for what to look for and how to best pick your camera.
There are many things to consider when buying a camera. The first thing to do is to figure out what your budget is. Camera prices range from tens of dollars for low-end ones to thousands and more. Decide how much money you would like to spend and what the usage of the camera will be. Try to answer questions such as: Are you going to take family photos? Shoot landscape photos? Travel a lot with the camera? Use a lot of flash photograph?
Once you have decided on the budget and the usage look for potential cameras and build a table with the price and features of each. Making the table is not hard but understanding what the various features practically mean and how important they are is trickier. Following is a list of important features and some explanations of what they really mean to you from a practical point of view:
Megapixels: New cameras are packed with an ever increasing number of mega pixels. Is more mega pixels better? A quick answer would be yes but a better answer would be it really depends. More mega pixels is important if you are going to print photos (especially enlargements) or if you are going to zoom in and crop fine details out of big photos. If you plan to watch your photos on your computer screen and maybe just print a few 4X6 prints every now and then than 2 mega pixels is more than enough (yes just 2). Most screen resolutions are about 1024X768 so even when viewing the photo in full screen mode you can only view 1024X768 which is less than 1 mega pixels. A 2 mega pixels 4X6 photo print will have a DPI higher than 300 which is more than enough for a high quality print.
If you plan to print photo enlargements than a rule of thumb is to be able to print at least 300DPI resolution. The following is a table for different print sizes and the needed mega pixels for such print quality:
page 4X6 2MP
page 5X7 3MP
page 8X10 7MP
page 11X14 14MP
page 16X20 28MP
page 20X30 54MP
Unless you budget is infinite when you buy a camera with more mega pixels you make a compromise between mega pixels and other features. For example is it better to spend money on more mega pixels or on better lenses? Or maybe on an external flash? It all depends on how you will use your camera. Evaluate your usage and decide what is more important to you.
Zoom: In some situations it is very useful to have a good zoom capability. For example when you take a portrait photo you want to make sure the objects face fills the photo frame while when you take a group photo you want to make sure everybody is in the photo frame. There are two types of zoom optical and digital. Optical zoom works by physically moving the cameras lenses and changing the focal length. By changing the focal length you can make objects appear bigger and fit the full photo frame. Digital zoom works by applying built-in software in the camera to define a portion of the photo which you are interested in. Once chosen the software crops the rest of the photo and enlarges the area you chose to fit the complete photo frame. The downside of this digital process is that the enlarged photo quality is lower than the original photos. The conclusion is that optical zoom is superior to digital zoom. In fact from a practical point of view digital zoom should not be considered zoom at all.
Some manufacturers state the cameras zoom figure without specifying if it is optical or digital. This information is confusing as many consumers do not understand the difference between the two. For example if a camera supports a 5X optical zoom and 10X digital zoom advertising the camera as a 10X zoom camera is confusing 10X digital zoom can be done with any camera using simple PC software.
When you compare different cameras zoom always compare their optical zoom capabilities. You can totally ignore the digital zoom figures.
Know your battery: As any portable electronic device digital cameras are powered by batteries. There are different battery technologies each with its cons and pros. Knowing your options can help you get a camera that better suits your needs. The first choice is disposable or rechargeable. Some cameras support both usually when using standard size batteries like AA, AAA.
Disposable batteries can only be used once. They usually have a standard size and shape such as AA, AAA. You can buy these batteries at most stores and once they are empty you can simply dispose of them
Rechargeable batteries can be used multiple times. Some rechargeable batteries have a standard size and shape such as AA or AAA. Such standard size batteries can be used anywhere that a disposable battery can. More often than not however rechargeable batteries have a proprietary shape and are compatible with just a few specific cameras. Once a rechargeable battery is empty you can place it in a special charger that will recharge it. The time it takes to recharge a battery, the number of times it can be charged and the life time of the battery are dependant on the technology used to build the battery.
There are pros and cons to using disposable or rechargeable batteries. The main advantage to using a disposable battery is that you can always buy a few to have with you to replace the ones that are empty and you can always get one in a store close-by in case you are stuck with empty batteries. The disadvantages to using disposable batteries are the cost of buying new batteries every time your batteries are empty and the capacity (in most cases a disposable battery will not last as long as a good rechargeable battery). On the other hand rechargeable batteries require only one purchase. When the battery is empty you can simply place it in its charger and after an hour or so you will have a fully recharged battery. The disadvantage is that if you run out of batteries during a photo shooting session or somewhere away from home or a power supply you can not just buy another battery. The solution to that problem is to buy one extra battery and to always carry it with you fully charged.
If you choose to use a rechargeable battery powered camera make sure that your camera uses the latest battery technologies. There are many type of rechargeable batteries usually named after the chemicals used to build them. Such technologies are: nickel cadium, nickel metal hybrid, lithium ion and lithium polymer. Without going to the details just remember that it is better to choose a battery that uses the latest technology which is a lithium polymer or lithium ion.
The real cost of ownership: the cost of owning a digital camera is not limited to the money paid to purchase the camera. In most cases you will find yourself spending more money on accessories and other additional products. Failing to budget for those extra expenses can result in buying a camera just to find out it is not operable without spending more.
When you calculate the real price of a camera and compare to your other options make sure that you take the following into account:
Memory card: Most cameras come with a basic low capacity memory card. Assess how much memory you will need and check the prices of such memory cards. Add that to the cameras cost.
Batteries: Check what batteries the camera uses and what batteries are included. Also check what the estimated battery life is. For example you probably need to buy an extra battery if your photo sessions are longer than the battery life. Check for the prices of compatible batteries and add it to the cameras cost.
PC connectivity: The most common methods of connectivity are USB and plugging the cameras memory card directly to the PC. Check if the camera includes the necessary cables and software. If it does not check the prices of buying the needed accessories and add that to the cameras cost.
Carrying case: Most cameras do not include a carrying case. If you will need a carrying case check for the prices of carrying cases that can fit your camera and add that cost to your cameras cost.
Lenses: Some cameras allow you to change lenses. Other cameras actually come without lenses at all you just buy the cameras body and get the lenses separately. Check what lenses are included with the camera and if you will need to buy lenses shop around for their prices. Lenses can be very expensive. Add the cost to the cameras cost.
In conclusion there are many things to consider when purchasing your next digital camera. It is important to understand what the different camera features practically mean to you. It is very easy to be tempted to get something just because of the ease of comparison or the hype in the market. The Mega pixels feature is a good example it is easy to compare this number and see which camera has more pixels. But in terms of photo quality there are many other factors like the lenses, the type of sensor and more. Do your homework by checking for prices online and in stores. Build a table of prices and features. Make the table relevant to you. Dont compare features that you do not care about they are just going to confuse you. Evaluate the true cost of owning the camera including all the accessories and addition costs.
There are many things to consider when buying a camera. The first thing to do is to figure out what your budget is. Camera prices range from tens of dollars for low-end ones to thousands and more. Decide how much money you would like to spend and what the usage of the camera will be. Try to answer questions such as: Are you going to take family photos? Shoot landscape photos? Travel a lot with the camera? Use a lot of flash photograph?
Once you have decided on the budget and the usage look for potential cameras and build a table with the price and features of each. Making the table is not hard but understanding what the various features practically mean and how important they are is trickier. Following is a list of important features and some explanations of what they really mean to you from a practical point of view:
Megapixels: New cameras are packed with an ever increasing number of mega pixels. Is more mega pixels better? A quick answer would be yes but a better answer would be it really depends. More mega pixels is important if you are going to print photos (especially enlargements) or if you are going to zoom in and crop fine details out of big photos. If you plan to watch your photos on your computer screen and maybe just print a few 4X6 prints every now and then than 2 mega pixels is more than enough (yes just 2). Most screen resolutions are about 1024X768 so even when viewing the photo in full screen mode you can only view 1024X768 which is less than 1 mega pixels. A 2 mega pixels 4X6 photo print will have a DPI higher than 300 which is more than enough for a high quality print.
If you plan to print photo enlargements than a rule of thumb is to be able to print at least 300DPI resolution. The following is a table for different print sizes and the needed mega pixels for such print quality:
page 4X6 2MP
page 5X7 3MP
page 8X10 7MP
page 11X14 14MP
page 16X20 28MP
page 20X30 54MP
Unless you budget is infinite when you buy a camera with more mega pixels you make a compromise between mega pixels and other features. For example is it better to spend money on more mega pixels or on better lenses? Or maybe on an external flash? It all depends on how you will use your camera. Evaluate your usage and decide what is more important to you.
Zoom: In some situations it is very useful to have a good zoom capability. For example when you take a portrait photo you want to make sure the objects face fills the photo frame while when you take a group photo you want to make sure everybody is in the photo frame. There are two types of zoom optical and digital. Optical zoom works by physically moving the cameras lenses and changing the focal length. By changing the focal length you can make objects appear bigger and fit the full photo frame. Digital zoom works by applying built-in software in the camera to define a portion of the photo which you are interested in. Once chosen the software crops the rest of the photo and enlarges the area you chose to fit the complete photo frame. The downside of this digital process is that the enlarged photo quality is lower than the original photos. The conclusion is that optical zoom is superior to digital zoom. In fact from a practical point of view digital zoom should not be considered zoom at all.
Some manufacturers state the cameras zoom figure without specifying if it is optical or digital. This information is confusing as many consumers do not understand the difference between the two. For example if a camera supports a 5X optical zoom and 10X digital zoom advertising the camera as a 10X zoom camera is confusing 10X digital zoom can be done with any camera using simple PC software.
When you compare different cameras zoom always compare their optical zoom capabilities. You can totally ignore the digital zoom figures.
Know your battery: As any portable electronic device digital cameras are powered by batteries. There are different battery technologies each with its cons and pros. Knowing your options can help you get a camera that better suits your needs. The first choice is disposable or rechargeable. Some cameras support both usually when using standard size batteries like AA, AAA.
Disposable batteries can only be used once. They usually have a standard size and shape such as AA, AAA. You can buy these batteries at most stores and once they are empty you can simply dispose of them
Rechargeable batteries can be used multiple times. Some rechargeable batteries have a standard size and shape such as AA or AAA. Such standard size batteries can be used anywhere that a disposable battery can. More often than not however rechargeable batteries have a proprietary shape and are compatible with just a few specific cameras. Once a rechargeable battery is empty you can place it in a special charger that will recharge it. The time it takes to recharge a battery, the number of times it can be charged and the life time of the battery are dependant on the technology used to build the battery.
There are pros and cons to using disposable or rechargeable batteries. The main advantage to using a disposable battery is that you can always buy a few to have with you to replace the ones that are empty and you can always get one in a store close-by in case you are stuck with empty batteries. The disadvantages to using disposable batteries are the cost of buying new batteries every time your batteries are empty and the capacity (in most cases a disposable battery will not last as long as a good rechargeable battery). On the other hand rechargeable batteries require only one purchase. When the battery is empty you can simply place it in its charger and after an hour or so you will have a fully recharged battery. The disadvantage is that if you run out of batteries during a photo shooting session or somewhere away from home or a power supply you can not just buy another battery. The solution to that problem is to buy one extra battery and to always carry it with you fully charged.
If you choose to use a rechargeable battery powered camera make sure that your camera uses the latest battery technologies. There are many type of rechargeable batteries usually named after the chemicals used to build them. Such technologies are: nickel cadium, nickel metal hybrid, lithium ion and lithium polymer. Without going to the details just remember that it is better to choose a battery that uses the latest technology which is a lithium polymer or lithium ion.
The real cost of ownership: the cost of owning a digital camera is not limited to the money paid to purchase the camera. In most cases you will find yourself spending more money on accessories and other additional products. Failing to budget for those extra expenses can result in buying a camera just to find out it is not operable without spending more.
When you calculate the real price of a camera and compare to your other options make sure that you take the following into account:
Memory card: Most cameras come with a basic low capacity memory card. Assess how much memory you will need and check the prices of such memory cards. Add that to the cameras cost.
Batteries: Check what batteries the camera uses and what batteries are included. Also check what the estimated battery life is. For example you probably need to buy an extra battery if your photo sessions are longer than the battery life. Check for the prices of compatible batteries and add it to the cameras cost.
PC connectivity: The most common methods of connectivity are USB and plugging the cameras memory card directly to the PC. Check if the camera includes the necessary cables and software. If it does not check the prices of buying the needed accessories and add that to the cameras cost.
Carrying case: Most cameras do not include a carrying case. If you will need a carrying case check for the prices of carrying cases that can fit your camera and add that cost to your cameras cost.
Lenses: Some cameras allow you to change lenses. Other cameras actually come without lenses at all you just buy the cameras body and get the lenses separately. Check what lenses are included with the camera and if you will need to buy lenses shop around for their prices. Lenses can be very expensive. Add the cost to the cameras cost.
In conclusion there are many things to consider when purchasing your next digital camera. It is important to understand what the different camera features practically mean to you. It is very easy to be tempted to get something just because of the ease of comparison or the hype in the market. The Mega pixels feature is a good example it is easy to compare this number and see which camera has more pixels. But in terms of photo quality there are many other factors like the lenses, the type of sensor and more. Do your homework by checking for prices online and in stores. Build a table of prices and features. Make the table relevant to you. Dont compare features that you do not care about they are just going to confuse you. Evaluate the true cost of owning the camera including all the accessories and addition costs.
Audio Options for HDTV
HDTV inherently provides a superior sound quality simply because the sound of HDTV is digitally transmitted. The difference in sound between an HDTV television and an analog television is rather noticeable. In fact, it is directly analogous to the difference between the music on CD's compared to the music on audiocassette tapes.
The difference in sound quality provided by HDTV televisions and programming does not end there. Many HDTV programs are also broadcast in Dolby Digital 5.1 surround sound, but in order to take full advantage of this technology, it is necessary to have the right equipment.
Dolby technology has been created by Dolby Laboratories, Inc. This technology is the most renowned provider of digital audio technology. Also, Dolby Laboratories is known for reliable and superior products. For these reasons, Dolby Digital Surround has become the standard for HDTV. Many television manufacturers substitute their own surround sound systems, but they cannot live up to the reputation and performance of Dolby. Therefore, it important to check the specs on an HDTV television before buying in order to ensure that it uses Dolby Digital Surround.
When using Dolby Digital Surround Sound, there are three options for set up. The first option is to buy a television with high quality center channel speakers, woofers, tweeters, and Dolby technology installed in the television. With this option, it is unnecessary to buy addition equipment to take advantage of Dolby Digital Surround Sound.
Another option for taking advantage of the Dolby Digital Surround Sound with an HDTV is to connect an external set of surround speakers to the television. With this option, the surround sound set up includes a front pair of speakers, a surround pair of speakers, a center channel, and a subwoofer. Sometimes, the front speakers are "powered towers." This means these towers include subwoofers.
The placement of these speakers is very important for the quality of the surround sound. The Center Channel Speaker should be centered either above or below the television. The Front Left and Right Speakers should be placed in an arc formation in line with the Center Channel Speaker. The Surround Left and Right Speakers, on the other hand, should be placed to the left and right sides behind the listening position. Many people choose to wall mount these speakers.
The third option for taking advantage of the Dolby Digital Surround System included in an HDTV television is to use an external set of front speakers can be connected to the HDTV television. This configuration is useful if there is not enough room to set up the external surround sound system and the HDTV does not come with Dolby Digital Surround installed. This isn't true surround sound, but it is a viable alternative to those who can't take advantage of the first two formats.
The audio and video outputs of the DVD or VCR can be connected to the AV receiver's video outputs. If a separate DVD and VCR need to be connected, one can be connected to the VCR1 connection and the other can be connected to the VCR2 connection. The AV receiver's VCR video and audio outputs should then be connected to the audio and video inputs of the DVD and/or VCR. In this way, the DVD and/or VCR will be able to record video signals that come through the AV receiver and the VHS tapes and/or DVD's will be able to be viewed on the HDTV.
To take full advantage of the Dolby Digital Surround Sound technology, one of the video outputs of the DVD player and/or VCR needs to be connected to the AV receiver. The digital coaxial audio or digital optical connection must also be connected to the AV receiver.
How do I connect my CD player?
A CD player can be connected to an AV receiver. The CD player's digital audio outputs can be used to connect the CD player to the AV receiver. A CD-Recorder can also be connected the AV receiver by using the Audio Tape Record/Playback input/output loop connections. In this way, the CD-Recorder will be able to function much like a standard audiocassette deck.
What else will I need?
Besides the basic electronic equipment needed to set up Dolby Digital Surround Sound, it is necessary to have connection cables. This includes video, audio, and loudspeaker connection cables. These cables need to be at an appropriate length in order to set the speakers in the proper position for optimal surround sound quality.
The difference in sound quality provided by HDTV televisions and programming does not end there. Many HDTV programs are also broadcast in Dolby Digital 5.1 surround sound, but in order to take full advantage of this technology, it is necessary to have the right equipment.
Dolby technology has been created by Dolby Laboratories, Inc. This technology is the most renowned provider of digital audio technology. Also, Dolby Laboratories is known for reliable and superior products. For these reasons, Dolby Digital Surround has become the standard for HDTV. Many television manufacturers substitute their own surround sound systems, but they cannot live up to the reputation and performance of Dolby. Therefore, it important to check the specs on an HDTV television before buying in order to ensure that it uses Dolby Digital Surround.
When using Dolby Digital Surround Sound, there are three options for set up. The first option is to buy a television with high quality center channel speakers, woofers, tweeters, and Dolby technology installed in the television. With this option, it is unnecessary to buy addition equipment to take advantage of Dolby Digital Surround Sound.
Another option for taking advantage of the Dolby Digital Surround Sound with an HDTV is to connect an external set of surround speakers to the television. With this option, the surround sound set up includes a front pair of speakers, a surround pair of speakers, a center channel, and a subwoofer. Sometimes, the front speakers are "powered towers." This means these towers include subwoofers.
The placement of these speakers is very important for the quality of the surround sound. The Center Channel Speaker should be centered either above or below the television. The Front Left and Right Speakers should be placed in an arc formation in line with the Center Channel Speaker. The Surround Left and Right Speakers, on the other hand, should be placed to the left and right sides behind the listening position. Many people choose to wall mount these speakers.
The third option for taking advantage of the Dolby Digital Surround System included in an HDTV television is to use an external set of front speakers can be connected to the HDTV television. This configuration is useful if there is not enough room to set up the external surround sound system and the HDTV does not come with Dolby Digital Surround installed. This isn't true surround sound, but it is a viable alternative to those who can't take advantage of the first two formats.
The audio and video outputs of the DVD or VCR can be connected to the AV receiver's video outputs. If a separate DVD and VCR need to be connected, one can be connected to the VCR1 connection and the other can be connected to the VCR2 connection. The AV receiver's VCR video and audio outputs should then be connected to the audio and video inputs of the DVD and/or VCR. In this way, the DVD and/or VCR will be able to record video signals that come through the AV receiver and the VHS tapes and/or DVD's will be able to be viewed on the HDTV.
To take full advantage of the Dolby Digital Surround Sound technology, one of the video outputs of the DVD player and/or VCR needs to be connected to the AV receiver. The digital coaxial audio or digital optical connection must also be connected to the AV receiver.
How do I connect my CD player?
A CD player can be connected to an AV receiver. The CD player's digital audio outputs can be used to connect the CD player to the AV receiver. A CD-Recorder can also be connected the AV receiver by using the Audio Tape Record/Playback input/output loop connections. In this way, the CD-Recorder will be able to function much like a standard audiocassette deck.
What else will I need?
Besides the basic electronic equipment needed to set up Dolby Digital Surround Sound, it is necessary to have connection cables. This includes video, audio, and loudspeaker connection cables. These cables need to be at an appropriate length in order to set the speakers in the proper position for optimal surround sound quality.
2007年9月26日星期三
Leonardo da Vinci - A Biography of the Renaissance Man
Leonardo Da Vinci was born on April 15, 1452, in Vinci, Italy. It is uncertain that Vinci, just west of Florence, was the actual birthplace and it is often debated that perhaps he was born in a farmhouse in Anchiano. Nevertheless, Vinci claims the prestigious title of the birthplace of Leonardo Da Vinci.
Leonardo did not author an autobiography; therefore, what little is know of his early life has been gathered from tax records and other documents of the period. What is known is that he was the illegitimate son of Ser Piero da Vinci and a woman who is only known by her first name, Catrina. It is speculated that she was possible a slave from the Middle East or perhaps just a lowly servant that worked in the household.
His father, a notary of some stature, did not raise him. It is known that Leonardo (christened Lionardo) lived with his. Later on he went to live with his father or his father's younger brother, Francesco. What became of his mother is unknown.
Because of the circumstances of his birth, Leonardo's early training was probably conducted by his step-mother, Donna Albiera, although he was mainly self-tought. Later on in life his illegitimacy would also influence his prospects for obtaining a higher education and the means to earn a living. When his father noted his artistic talent, he was sent to Florence as apprentice to Andrea del Verrocchio at around the age of 16 or 17.
Under Verrocchio, Leonardo studied painting and sculpture. He probably learned geometry during his apprenticeship and worked with other students and artists of the time such as Sandro Botticelli, Cosimo Rosselil and Lorenzo di Credi. It was during this time that he was assigned his first task of painting the angel in Baptism of Christ (c.1472-75). After seeing Leonardo's angel it is said that Verrocchio swore "never to pick up a paintbrush again".
During his first Florentine period (1478-1483) Leonardo received some of his first commissions. He became known for his artistic talents with his work on Madonna and Child (c. 1478), Small Annunciation (1480-1481), and Adoration of the Magi (c. 1481-82).
Leonardo was revered by friends and colleagues as being handsome and charismatic. He was kind and generous and probably one of the world's first animal rights activists. He was also a practicing vegetarian (almost unknown in the fifteenth century.) However, he was not so well liked that he was immune to gossip and in 1476 he was arrested on the charge of sodomy. After about two months of incarceration he was released due to a lack of evidence. The question of his sexuality still remains a mystery.
After his release in 1478, Leonardo left Florence for the first time and traveled to Milan. There he joined a new patron, Ludovico Sforza. Initially he was to have been a military engineer, but instead became the court artist. He designed several machines such as catapults and armored cars but none were ever built. During this time he also painted one of his most famous frescos, The Last Supper - not actually a fresco in the true sense of the word but still paramount in establishing him as a portraitist and artist.
In 1499, Leonardo returned to Florence where he accepted a commission for an altar painting for the friars of the Order of the Servites at Santissima Annunziata. It was for this painting that Leonardo created one of his unfinished masterpieces, The Burlington House Cartoon (c.1499-1500). He also started two of his most famous works, The Battle of Anghiari, and The Mona Lisa (1503). The Battle of Anghiari was never finished and The Mona Lisa was never delivered to the client, Francesco del Giocondo.
In 1506 he headed back to Milan, remaining there for six years to continue his anatomy studies. Then in 1511, he moved to Rome where he continued his experiments with flight and optical puzzles as well as botany and the scientific mixing of oil paints and varnishes.
In 1516 Leonardo joined the King of France, Francois I, in the Loire Valley. The aging artist was ill and suffering from a stroke. Unable to paint, he undertook several projects including a walking mechanical lion. Instead of a heart, the lion's chest opened to reveal a fleur-de-lis. He also designed a palace at Romorantin, reorganized his notebooks, and several other smaller projects.
On May 2, 1519, Leonardo died and was buried in Saint-Forentine in Amboise. But even in death, his travels were not over. During the Wars of Religion Leonardo's remains were moved several times. Eventually he was buried in the Chapel of St. Hubert in the castle of Amboise.
Leonardo da Vinci was an artist, musician, philosopher, engineer, botanist, anatanomist, mathematician and a humanitarian. He did not believe in life after death and he did not agree with the teachings of the church. He was generous but suspicious. He questioned everything around him and excelled at everything he undertook. He spent 30 years keeping meticulous records and journals documenting his experiments and designs. Vassari observes with reference to Leonardo's writings, "he wrote backwards in rude characters, and with the left hand, so that anyone who is not practiced in reading them, cannot understand them". He did not number the five thousand pages he documented but ensured that each observation or experiment documented be completed on one page. Leonardo took great pains to finish his notebooks. Yet, in contrast to his scientific studies, this artist who epitomizes the Renaissance left much of his artistic endeavors unfinished.
Much of Leonardo's life is a mystery in spite of his writings. Little is known of the man inside the body because he did not reveal much to the world. His accomplishments throughout his 67 years on earth did much to revolutionize the artistic community and, had his machines been built, would have revolutionized society centuries in advance. Leonardo was truly a man before his time.
Leonardo did not author an autobiography; therefore, what little is know of his early life has been gathered from tax records and other documents of the period. What is known is that he was the illegitimate son of Ser Piero da Vinci and a woman who is only known by her first name, Catrina. It is speculated that she was possible a slave from the Middle East or perhaps just a lowly servant that worked in the household.
His father, a notary of some stature, did not raise him. It is known that Leonardo (christened Lionardo) lived with his. Later on he went to live with his father or his father's younger brother, Francesco. What became of his mother is unknown.
Because of the circumstances of his birth, Leonardo's early training was probably conducted by his step-mother, Donna Albiera, although he was mainly self-tought. Later on in life his illegitimacy would also influence his prospects for obtaining a higher education and the means to earn a living. When his father noted his artistic talent, he was sent to Florence as apprentice to Andrea del Verrocchio at around the age of 16 or 17.
Under Verrocchio, Leonardo studied painting and sculpture. He probably learned geometry during his apprenticeship and worked with other students and artists of the time such as Sandro Botticelli, Cosimo Rosselil and Lorenzo di Credi. It was during this time that he was assigned his first task of painting the angel in Baptism of Christ (c.1472-75). After seeing Leonardo's angel it is said that Verrocchio swore "never to pick up a paintbrush again".
During his first Florentine period (1478-1483) Leonardo received some of his first commissions. He became known for his artistic talents with his work on Madonna and Child (c. 1478), Small Annunciation (1480-1481), and Adoration of the Magi (c. 1481-82).
Leonardo was revered by friends and colleagues as being handsome and charismatic. He was kind and generous and probably one of the world's first animal rights activists. He was also a practicing vegetarian (almost unknown in the fifteenth century.) However, he was not so well liked that he was immune to gossip and in 1476 he was arrested on the charge of sodomy. After about two months of incarceration he was released due to a lack of evidence. The question of his sexuality still remains a mystery.
After his release in 1478, Leonardo left Florence for the first time and traveled to Milan. There he joined a new patron, Ludovico Sforza. Initially he was to have been a military engineer, but instead became the court artist. He designed several machines such as catapults and armored cars but none were ever built. During this time he also painted one of his most famous frescos, The Last Supper - not actually a fresco in the true sense of the word but still paramount in establishing him as a portraitist and artist.
In 1499, Leonardo returned to Florence where he accepted a commission for an altar painting for the friars of the Order of the Servites at Santissima Annunziata. It was for this painting that Leonardo created one of his unfinished masterpieces, The Burlington House Cartoon (c.1499-1500). He also started two of his most famous works, The Battle of Anghiari, and The Mona Lisa (1503). The Battle of Anghiari was never finished and The Mona Lisa was never delivered to the client, Francesco del Giocondo.
In 1506 he headed back to Milan, remaining there for six years to continue his anatomy studies. Then in 1511, he moved to Rome where he continued his experiments with flight and optical puzzles as well as botany and the scientific mixing of oil paints and varnishes.
In 1516 Leonardo joined the King of France, Francois I, in the Loire Valley. The aging artist was ill and suffering from a stroke. Unable to paint, he undertook several projects including a walking mechanical lion. Instead of a heart, the lion's chest opened to reveal a fleur-de-lis. He also designed a palace at Romorantin, reorganized his notebooks, and several other smaller projects.
On May 2, 1519, Leonardo died and was buried in Saint-Forentine in Amboise. But even in death, his travels were not over. During the Wars of Religion Leonardo's remains were moved several times. Eventually he was buried in the Chapel of St. Hubert in the castle of Amboise.
Leonardo da Vinci was an artist, musician, philosopher, engineer, botanist, anatanomist, mathematician and a humanitarian. He did not believe in life after death and he did not agree with the teachings of the church. He was generous but suspicious. He questioned everything around him and excelled at everything he undertook. He spent 30 years keeping meticulous records and journals documenting his experiments and designs. Vassari observes with reference to Leonardo's writings, "he wrote backwards in rude characters, and with the left hand, so that anyone who is not practiced in reading them, cannot understand them". He did not number the five thousand pages he documented but ensured that each observation or experiment documented be completed on one page. Leonardo took great pains to finish his notebooks. Yet, in contrast to his scientific studies, this artist who epitomizes the Renaissance left much of his artistic endeavors unfinished.
Much of Leonardo's life is a mystery in spite of his writings. Little is known of the man inside the body because he did not reveal much to the world. His accomplishments throughout his 67 years on earth did much to revolutionize the artistic community and, had his machines been built, would have revolutionized society centuries in advance. Leonardo was truly a man before his time.
Designing A Data Storage Plan For Your Business
If the term "data storage architecture" makes your lip curl, chances are that you've been procrastinating on implementing a storage solution for your data worthy of your critical business data. Data storage architecture can be a complicated rabbit hole of acronyms that can cause just about anyone's head to spin. In this article, we'll explore some simple ways to determine the right type of storage plan for your business.
The good news is that you don't have to try and design your entire storage structure alone and you don't need to fork out tons of money for an architectural consultant. Instead, spend you money on better systems and equipment to protect your data. Data storage VAR's, or Value Added Resellers are an ideal resource for unbiased storage consultation.
A value added reseller is one that adds, you guessed it, value to the process of buying data storage products by also offering consultation. VAR's don't work for any one specific company so you won't be suckered into buying an inferior brand by a company sales rep. Value added reseller representatives are consultants experienced with the technology and their only "bias" comes from their experience and research of working with different brands and storage types.
Unfortunately for the majority of us, storage for you data is not a one size fits all solution. Some businesses will benefit from storing their data on tape media, some will be better off with disk storage, others with optical jukeboxes, and still other that require a combination of two or more types. While a small, single person home business may be just fine with secondary disk storage device, a doctor's office with thousands of patient records will probably require a tape storage with and automated tape library system to back up data on a regularly scheduled basis.
Either way, your company's data probably isn't something that you want to experiment with through trial and error of different types of storage devices for your data. Whether you're the small home business, the doctor's office, or a large corporation, data storage value added resellers can help you to develop a storage game plan at no additional cost above and beyond the normal selling price of the data storage products.
So if you're like many business owners, you've been meaning to spend some time learning about data storage architecture before implementing a storage strategy. When you consult with a VAR, there's no reason to procrastinate or lose several weekend trying to learn about SAN's, iSCSI, LAN's, and the like. Find a reputable value added reseller, and they'll know just the right questions to ask you to help you find the ideal solution for your company's data storage needs.
The good news is that you don't have to try and design your entire storage structure alone and you don't need to fork out tons of money for an architectural consultant. Instead, spend you money on better systems and equipment to protect your data. Data storage VAR's, or Value Added Resellers are an ideal resource for unbiased storage consultation.
A value added reseller is one that adds, you guessed it, value to the process of buying data storage products by also offering consultation. VAR's don't work for any one specific company so you won't be suckered into buying an inferior brand by a company sales rep. Value added reseller representatives are consultants experienced with the technology and their only "bias" comes from their experience and research of working with different brands and storage types.
Unfortunately for the majority of us, storage for you data is not a one size fits all solution. Some businesses will benefit from storing their data on tape media, some will be better off with disk storage, others with optical jukeboxes, and still other that require a combination of two or more types. While a small, single person home business may be just fine with secondary disk storage device, a doctor's office with thousands of patient records will probably require a tape storage with and automated tape library system to back up data on a regularly scheduled basis.
Either way, your company's data probably isn't something that you want to experiment with through trial and error of different types of storage devices for your data. Whether you're the small home business, the doctor's office, or a large corporation, data storage value added resellers can help you to develop a storage game plan at no additional cost above and beyond the normal selling price of the data storage products.
So if you're like many business owners, you've been meaning to spend some time learning about data storage architecture before implementing a storage strategy. When you consult with a VAR, there's no reason to procrastinate or lose several weekend trying to learn about SAN's, iSCSI, LAN's, and the like. Find a reputable value added reseller, and they'll know just the right questions to ask you to help you find the ideal solution for your company's data storage needs.
Optical Aids to Help You Cope with Low Vision
Low vision aids come in all shapes and sizes and serve a multitude of different purposes. A one-size-fits-all approach just won't do when it comes to choosing these devices, especially when you consider that a very wide range of eye problems can cause low vision.
Age-related macular degeneration, diabetic retinopathy, glaucoma, cataracts, head trauma and stroke can all result in reduced visual acuity, reduced contrast sensitivity and glare sensitivity. It should be remembered that these eye conditions often involve impaired color vision, and that the majority of sufferers are over 60.
This is why many of the more high-tech low vision aids now coming on to the market offer customised viewing nodes (magnifiers, for example, which allow material to be viewed in black and white, blue and yellow or black and yellow) or adjustable image brightness.
Customisation need not always be high-tech, however. It can be as simple as fitting a magnifier with a flexible, adjustable arm so obviating the need to look upward at an uncomfortable angle. The tilting screen of a video magnifier or simply a stand magnifier can make for greatly increased ease of viewing when arthritis is as much of a problem as low vision.
Of course, not everyone requires a high-tech solution to their eye problems. Various small, hand-held magnifiers are available from your local drug store which can often be of some assistance in the early stages of failing eyesight.
With hand magnifiers it is usually the case that practice makes perfect. Often a bit of a struggle at the outset, best results can be achieved by holding these low vision aids straight. Your eye, the magnifier and the particular material you're looking at should all be exactly aligned. Distortion will result from tilting the magnifier.
If you use a stand magnifier, keep the magnifier on the paper and break yourself of the habit of raising the magnifier to your eyes. Again, distortion of the material and the need to constantly refocus, will tire even more aging eyes with a low vision problem.
A professional consultation should be sought, though, if and when they prove to be less helpful in reading and writing. Specialists in low vision will assess the degree of your visual impairment. They might prescribe special lenses which incorporate a miniature telescopic unit. These will enable you to resolve fine details through the telescope while using the regular lens for peripheral vision.
Or, perhaps, they will show you precisely the type of lighting you need to use in order to maximise the vision that remains. Reading lamps are now available which filter out damaging, blue light radiation and deliver optimal contrast for sufferers of low vision.
When greater magnification is needed, the newest low vision aids offer features which will give you a true independence in carrying out daily tasks. Many combine portability with choice of viewing modes to suit your individual needs.
One of the more popular high-tech aids is the video magnifier or closed circuit television. Free-standing units consist of a stand-mounted video camera which projects magnified images on to a video screen. They are very useful for reading and writing, as well as doing craftwork. For many people, with hobbies requiring intricate, close-up work, this is a quality of life issue.
However, CCTVs, which are portable, provide you with the greatest flexibility of all. Advances have been made on the older type of portable video magnifiers. These could be plugged into a television, and by rolling a device about the size of a computer mouse across the reading material, you would see a magnified image appear on the TV.
Today, truly portable CCTVs are now being designed where a similar mouse-like device is used, but no TV is needed to view the magnified image. Instead it appears in a pair of goggles you wear.
More convenient still if you're out and about, the wonders of miniaturisation have made it possible to develop a new generation of very small, light-weight video magnifiers. These are ideal for letting you read grocery labels, restaurant menus and receipts. Some also come complete with a folding writing stand which will allow you to write as well.
For distance viewing, portable telescopic devices allow you to follow the game better at sporting events or to watch a theatre production. These aids carry many features which promote ease of use - low light compensation, high levels of magnification and contrast enhancement, for example.
Many people, though, prefer to use another sense for reading: their hearing. They use reading machines (scanners with voice output) to transform written material into the spoken word. For avid readers, and those who want the ultimate in comfort, these low vision aids offer an ideal solution to their low vision problems. Hooked up to a computer, and using specially-designed software, your PC can instantly be turned into a "reading machine".
Unfortunately, whatever you choose, you will not be able to turn back the clock. Low vision aids will not replace vision that has already deteriorated or been lost. Fortunately, however, we live in a world where new devices are being designed all the time enabling us all to optimise the vision we have left and enjoy life to the full.
Age-related macular degeneration, diabetic retinopathy, glaucoma, cataracts, head trauma and stroke can all result in reduced visual acuity, reduced contrast sensitivity and glare sensitivity. It should be remembered that these eye conditions often involve impaired color vision, and that the majority of sufferers are over 60.
This is why many of the more high-tech low vision aids now coming on to the market offer customised viewing nodes (magnifiers, for example, which allow material to be viewed in black and white, blue and yellow or black and yellow) or adjustable image brightness.
Customisation need not always be high-tech, however. It can be as simple as fitting a magnifier with a flexible, adjustable arm so obviating the need to look upward at an uncomfortable angle. The tilting screen of a video magnifier or simply a stand magnifier can make for greatly increased ease of viewing when arthritis is as much of a problem as low vision.
Of course, not everyone requires a high-tech solution to their eye problems. Various small, hand-held magnifiers are available from your local drug store which can often be of some assistance in the early stages of failing eyesight.
With hand magnifiers it is usually the case that practice makes perfect. Often a bit of a struggle at the outset, best results can be achieved by holding these low vision aids straight. Your eye, the magnifier and the particular material you're looking at should all be exactly aligned. Distortion will result from tilting the magnifier.
If you use a stand magnifier, keep the magnifier on the paper and break yourself of the habit of raising the magnifier to your eyes. Again, distortion of the material and the need to constantly refocus, will tire even more aging eyes with a low vision problem.
A professional consultation should be sought, though, if and when they prove to be less helpful in reading and writing. Specialists in low vision will assess the degree of your visual impairment. They might prescribe special lenses which incorporate a miniature telescopic unit. These will enable you to resolve fine details through the telescope while using the regular lens for peripheral vision.
Or, perhaps, they will show you precisely the type of lighting you need to use in order to maximise the vision that remains. Reading lamps are now available which filter out damaging, blue light radiation and deliver optimal contrast for sufferers of low vision.
When greater magnification is needed, the newest low vision aids offer features which will give you a true independence in carrying out daily tasks. Many combine portability with choice of viewing modes to suit your individual needs.
One of the more popular high-tech aids is the video magnifier or closed circuit television. Free-standing units consist of a stand-mounted video camera which projects magnified images on to a video screen. They are very useful for reading and writing, as well as doing craftwork. For many people, with hobbies requiring intricate, close-up work, this is a quality of life issue.
However, CCTVs, which are portable, provide you with the greatest flexibility of all. Advances have been made on the older type of portable video magnifiers. These could be plugged into a television, and by rolling a device about the size of a computer mouse across the reading material, you would see a magnified image appear on the TV.
Today, truly portable CCTVs are now being designed where a similar mouse-like device is used, but no TV is needed to view the magnified image. Instead it appears in a pair of goggles you wear.
More convenient still if you're out and about, the wonders of miniaturisation have made it possible to develop a new generation of very small, light-weight video magnifiers. These are ideal for letting you read grocery labels, restaurant menus and receipts. Some also come complete with a folding writing stand which will allow you to write as well.
For distance viewing, portable telescopic devices allow you to follow the game better at sporting events or to watch a theatre production. These aids carry many features which promote ease of use - low light compensation, high levels of magnification and contrast enhancement, for example.
Many people, though, prefer to use another sense for reading: their hearing. They use reading machines (scanners with voice output) to transform written material into the spoken word. For avid readers, and those who want the ultimate in comfort, these low vision aids offer an ideal solution to their low vision problems. Hooked up to a computer, and using specially-designed software, your PC can instantly be turned into a "reading machine".
Unfortunately, whatever you choose, you will not be able to turn back the clock. Low vision aids will not replace vision that has already deteriorated or been lost. Fortunately, however, we live in a world where new devices are being designed all the time enabling us all to optimise the vision we have left and enjoy life to the full.
Great Spectacles In Venice: Make Venice vacations An Enjoyable Experience
A Venice vacation is nothing if not steeped in tradition. In fact, ever since the city has become a popular tourist attraction where visitors probably outnumber natives by a factor of ten, the traditions have become more pronounced, more colorful, and more enjoyable and yes, more orthodox. Let us see a few of the major tourist attractions in Venice that you can enjoy during your Venice vacations.
Marriage to the Sea
On Ascension Day every year, the city recreates its marriage to the sea to emphasize the fact that the city is indeed totally dependent on the sea. The Doge is taken to S. Nicolu del Lido in his traditional boat. There is a great colorful parade of ships, boats and gondolas of all sizes escorting him, and with great pomp and gaiety he throws a wedding ring in to the middle of the lagoon. The show carries on for quite some time and is followed by enthusiastic races among gondola drivers. This is a must see in your itinerary during the Venice vacation.
Carnival
The carnival in Venice, Italy has a flavor unparalleled anywhere else. For ten days. Venice is a hotbed of activities and locals and tourists alike take part in the dancing and entertainment with great gusto. St Marks Square is the hub of main activities but fortunately, the carnival is celebrated all over town in a large number of dancing halls and the crowds are somewhat distributed. The carnival is one of the most important tourist attractions in Venice and you should plan your Venice vacations accordingly. The masks are a must have for the carnival and the very notion of being masked gives a certain abandon to the proceedings. Carnival or not, every tourist is bound to carry a mask or two back home.
The Historic Regatta
If the city has a hundred and fifty waterways and canals, can a boat race be far behind? Every year, the regatta of hundreds of boats speeding past thousands of tourists enjoying their Venice vacations and locals, all loudly cheering whichever boat takes their fancy, is a major spectacle. There is not just one regatta alone. Although part of one event, there are races for champions, the gondolini, for women, the mascarete and for the young, the pupparini. Huge crowds, loud cheering and colorful stands are the highlight to a fun and frolic filled day!
The Festival of the Redeemer
If you look at Venice history, In 1576, a plague hit Venice. Legend has it that it was brought into the city by rats carried on a ship from the Orient. Thousands died till finally, the plague was contained in 1630! The celebrations continue to this day and are held on the third Sunday of July. All monuments are lighted up and a beautiful fireworks display lights up the entire lagoon far into the night.
No matter which season you select for your Venice vacations, there is bound to be something spectacular to attract. After all, Venice is not a historical odyssey for nothing.
Marriage to the Sea
On Ascension Day every year, the city recreates its marriage to the sea to emphasize the fact that the city is indeed totally dependent on the sea. The Doge is taken to S. Nicolu del Lido in his traditional boat. There is a great colorful parade of ships, boats and gondolas of all sizes escorting him, and with great pomp and gaiety he throws a wedding ring in to the middle of the lagoon. The show carries on for quite some time and is followed by enthusiastic races among gondola drivers. This is a must see in your itinerary during the Venice vacation.
Carnival
The carnival in Venice, Italy has a flavor unparalleled anywhere else. For ten days. Venice is a hotbed of activities and locals and tourists alike take part in the dancing and entertainment with great gusto. St Marks Square is the hub of main activities but fortunately, the carnival is celebrated all over town in a large number of dancing halls and the crowds are somewhat distributed. The carnival is one of the most important tourist attractions in Venice and you should plan your Venice vacations accordingly. The masks are a must have for the carnival and the very notion of being masked gives a certain abandon to the proceedings. Carnival or not, every tourist is bound to carry a mask or two back home.
The Historic Regatta
If the city has a hundred and fifty waterways and canals, can a boat race be far behind? Every year, the regatta of hundreds of boats speeding past thousands of tourists enjoying their Venice vacations and locals, all loudly cheering whichever boat takes their fancy, is a major spectacle. There is not just one regatta alone. Although part of one event, there are races for champions, the gondolini, for women, the mascarete and for the young, the pupparini. Huge crowds, loud cheering and colorful stands are the highlight to a fun and frolic filled day!
The Festival of the Redeemer
If you look at Venice history, In 1576, a plague hit Venice. Legend has it that it was brought into the city by rats carried on a ship from the Orient. Thousands died till finally, the plague was contained in 1630! The celebrations continue to this day and are held on the third Sunday of July. All monuments are lighted up and a beautiful fireworks display lights up the entire lagoon far into the night.
No matter which season you select for your Venice vacations, there is bound to be something spectacular to attract. After all, Venice is not a historical odyssey for nothing.
Taking Portrait Photos with Blurry Background and Understanding Depth of Field
We have all seen beautiful photos where the object is perfectly focused while the background is blurred. Such a photo can be very dramatic and might seem to be hard to shoot. In this article we will give you a few tips on how to shoot blurry background photos that will impress your friends and family. You will also understand what Depth of Field is and how to control it.
Depth of field (also known as DOF for short) is the most important thing to understand before shooting a blurry background photo. Depth of field is defined as the range in which the photo is in focus. For example an infinite depth of field means that the photo will be in focus from a certain distance from the camera and up to infinity. When taking a blurry photo the goal is to set the depth of field just around the object. In this way the object is in focus while the background behind it is not.
How do you control the depth of field? After all there is no depth of field menu in the camera (wouldnt that be nice). Depth of field is an optical figure that is influenced by a few factors:
The distance of the object from the camera: This is obvious to understand when taken to the extreme. Shooting an object 10 feet from the camera will result in a smaller depth of field than shooting an object 100 feet from the camera. Obviously shooting an object which for all practical purpose is infinite distance from the camera will result in the camera focused on infinity and the depth of field being infinite too..
The aperture: The wider the aperture (f number decreases) the smaller the depth of field and vice versa: the narrower the aperture (f number increases) the greater the depth of field. Just remember that the depth of field changes along with the f number: when the f number increases and depth of field increases and vice versa. Unfortunately you can not just change the aperture as you wish. Changing the aperture results in a need to change the shutter speed (either manually or the camera can most likely do that for you automatically). The wider the aperture the more light that penetrates the lens and the faster the shutter speed needs to be so there is a limit to how wide you can set the aperture to.
The focal length of the lens: The shorter the focal length the greater the depth of field and vice versa the longer the focal length the smaller the depth of field. For example if you use normal lenses at somewhere around 50mm your depth of field will be much greater than if you use zoom lenses at 200mm. With long focal length the depth of field can be extremely small. For that reason zoom lenses are a good choice in order to shoot a good blurry photo that is practically focused only on the object.
After understanding the theory it is best to go to the field an experiment. You will get a sense of how your photo will look like and how blurry the background will be after playing with different lenses, different apertures and different distances from your object. If you own zoom lenses start with taking photos of a relatively close object while using your zoom lenses. You will find out that it is extremely easy to get a blurry background photo using this method even without setting the aperture. Once you feel comfortable with that setup start changing the aperture and also change to your normal 18mm-55mm or similar lenses.
Most cameras allow to manually change the aperture by putting the camera in A mode while you are changing the aperture the camera will automatically set the shutter speed accordingly. Some cameras allow you to manually set both aperture and shutter speed.
In conclusion shooting dramatic blurry background photos is easy with some minimal understanding of depth of field and some experimenting.
Depth of field (also known as DOF for short) is the most important thing to understand before shooting a blurry background photo. Depth of field is defined as the range in which the photo is in focus. For example an infinite depth of field means that the photo will be in focus from a certain distance from the camera and up to infinity. When taking a blurry photo the goal is to set the depth of field just around the object. In this way the object is in focus while the background behind it is not.
How do you control the depth of field? After all there is no depth of field menu in the camera (wouldnt that be nice). Depth of field is an optical figure that is influenced by a few factors:
After understanding the theory it is best to go to the field an experiment. You will get a sense of how your photo will look like and how blurry the background will be after playing with different lenses, different apertures and different distances from your object. If you own zoom lenses start with taking photos of a relatively close object while using your zoom lenses. You will find out that it is extremely easy to get a blurry background photo using this method even without setting the aperture. Once you feel comfortable with that setup start changing the aperture and also change to your normal 18mm-55mm or similar lenses.
Most cameras allow to manually change the aperture by putting the camera in A mode while you are changing the aperture the camera will automatically set the shutter speed accordingly. Some cameras allow you to manually set both aperture and shutter speed.
In conclusion shooting dramatic blurry background photos is easy with some minimal understanding of depth of field and some experimenting.
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