Using Supercomputers for Computer RAM Upgrade
[b]ABSTRACT[/b]
Supercomputers have been used for several applications beneficial to man. There are improvements to supercomputers yearly; as their proficiency is increased, it extends their usefulness also. Supercomputers are mainframe computers among the most powerful at any given time; having high processing speed and very large memory size. This memory can be programmed to be shared with computers around the world. Computer programs written for this purpose will enable a supercomputer share parts of its memory with computers. The shared memory will be available to upgrade the Random Access Memory (RAM) of computers. Usually, computer RAM upgrade is done manually by manufacturers or technicians as in Local I/O, making the memory size available same at a given time unless replaced manually. This paper presents that RAM of computers or devices can be upgraded using programmed software connected to the internet. A first time user connects to the internet, downloads’ the software and request for certain byte of memory from the supercomputer. The software acts as the ‘virtual’ RAM for the extra memory provided at the time. The RAM of a computer can be used by programs to perform necessary tasks while the computer is on; it is an integrated circuit memory chip that allows information to be stored or accessed in any order and all storage locations are equally accessible. It comes with a predetermined size. With the application described in this paper, memory size larger than predetermined can be made available to computers at anytime.
1.0 [b] INTRODUCTION[/b]
The objective of this research is to provide an alternative to manual upgrades for Random Access Memory (RAM) of computers. A computer user from anywhere in the world can boost the RAM of his computer while in use by requesting via the internet for a certain amount of memory from the server.
The server is the Supercomputer with a high processing speed and very large memory. The server will be programmed to share some of its memory to computers that sends it request via the Internet.
The RAM to be provided for the computer will be available for use while the computer is ON, just as the RAM of computers is used only when the computer is in use. When the system is switched on, a user can lunch the software and request certain size of memory from the server via the Internet.
Virus protection for your computer in simple English
<p> Computers can capture virus, like we do. When the computer gets sick, the anti-virus software as a medicine. If it is strong and fit, need antivirus software as an added defense against a virus attack. Computer virus spread around like human virus. It spreads through e-mail to your friend virus-infected files, or copy it to your friends in a virus infected file. When the computer catches a virus, it may be one or more of the following syndromes.<p> – Computer will not boot properly. Error massage came during startup.<p> – Application not working properly.<p> – USB disk or disks can not be read.<p> – Printer will not print.<p> – Pulldown menus are not the same as before.<p> – Disk turns suddenly without reason.<p> – Unusual error messages.<p> – Computer slow or freezes.<p> – Computer crashes.<p> – Files lost!<p> – Files corrupt and can not be read.<p> The files on your computer, you observed:<p> – File size changes for no reason.<p> – Changed date does not match the date of last use.<p> – An increase in the number of cases in which nothing is added. To prevent one of these catastrophic events occur on your computer. It is essential to protect your computer.<p> An anti-virus software might be your answer to most of these problems. Why do I say anti-virus software may be the answer to most of these questions? Because some of the above problems are not the cause of a virus.<p> Some may be caused by:<p> – Software loaded on your computer without your knowledge. The purpose of this software on your computer activities to follow or even get some information from your computer without your knowledge! This type of software commonly known as spyware. (You can use anti-spyware software from here.)<p> – Computer hard disk is almost no space. This will cause the computer to slow down.<p> – Too many programs are running in the computer. Background programs loaded on your computer every time you start your computer. If the computer does not have enough memory to handle all these programs will cause the computer to slow down.<p> – The computer can run a schedule program you might not notice. Some time such programs are loaded on the computer when it is installed. The manufacturer believes it is imperative that the computer program is executed at regular intervals. Example of this software: Windows Updater Anti Virus software (. It is important to use anti-virus software up to date), Backup program, etc.<p> – Too many programs are running in the computer at the same time.<p> Yet it is still very important to an anti-virus software loaded, updated and running in your computer. However, no antivirus software helps you to remove or completely clean all viruses. It is therefore important for the virus to prevent attacks on your computer. So an anti-virus software, the first software program to be loaded and run on your computer. You need anti-virus software update right after you’ve loaded into your computer.<p> It is very important to keep your anti-virus software regularly updated. New viruses are discovered often, do not update your anti-virus software, this new virus to attack your computer easily.<p> What if you already use your computer loaded with all your important information and you have no anti-virus software on your computer? Then you can not slow down and you need an antivirus software loaded, updated and scanned immediately. After the anti-virus software is updated, restart your computer. Start scanning your computer before you run a program. If no virus is found, you’re a lucky winner. If there is, choose a solution that anti-virus software is recommended.<p> What if, after the computer scanned and virus is found. And you have chosen the solution that the anti-virus software to recommend, but the software says it can not be cleaned. You can delete or quarantine. Then you have a problem. If you are absolutely sure that you and the computer does not need the file, then delete or quarantine. If the file is critical to your computer, then you need a single file that is not infected with the virus to replace the infected file, if you can find it. If your file, you can to do the same.<p> You also need to restart the computer and runs anti-virus software again to confirm that the computer is free from virus. When infected with viruses too much or too many viruses can not be cleaned, a total software to recover your computer. If you backup your computer regularly, you can restore your last backup. Provided that the last backup is virus free. That means you have to do anti-virus scan of your computer after you restore your computer from the backup files.<p> You do not have two antivirus software. It is good to have at least two antivirus software on your computer. It will constantly monitor your computer for viruses and other activities will scan your computer for viruses just when you want. However, you must be at least one anti-virus software installed if your computer slows down considerably after two anti-virus software installed.<p> It is very important. You must keep your antivirus software regularly and scan regularly. It is good to the antivirus software company recommendation to follow.
Need help withfixing a slow computer ask a question at wwdn.org
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computer virus
brief intro on computer virus
A computer virus is a computer program that can copy itself and infect a computer without the permission or knowledge of the owner. The term “virus” is also commonly but erroneously used to refer to other types of malware, adware, and spyware programs that do not have the reproductive ability. A true virus can only spread from one computer to another (in some form of executable code) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disk, CD, DVD, or USB drive. Viruses can increase their chances of spreading to other computers by infecting files on a network file system or a file system that is accessed by another computer. The term “computer virus” is sometimes used as a catch-all phrase to include all types of malware. Malware includes computer viruses, worms, trojan horses, most rootkits, spyware, dishonest adware, crimeware, and other malicious and unwanted software), including true viruses. Viruses are sometimes confused with computer worms and Trojan horses, which are technically different. A worm can exploit security vulnerabilities to spread itself to other computers without needing to be transferred as part of a host, and a Trojan horse is a program that appears harmless but has a hidden agenda. Worms and Trojans, like viruses, may cause harm to either a computer system’s hosted data, functional performance, or networking throughput, when they are executed. Some viruses and other malware have symptoms noticeable to the computer user, but many are surreptitious. Most personal computers are now connected to the Internet and to local area networks, facilitating the spread of malicious code. Today’s viruses may also take advantage of network services such as the World Wide Web, e-mail, Instant Messaging, and file sharing systems to spread.
history
Creeper virus was first detected on ARPANET, the forerunner of the Internet in the early 1970s.
Creeper was an experimental self-replicating program written by Bob Thomas at BBN in 1971. Creeper used the ARPANET to infect DEC PDP-10 computers running the TENEX operating system. Creeper gained access via the ARPANET and copied itself to the remote system where the message, “I’m the creeper, catch me if you can!” was displayed. The Reaper program was created to delete Creeper.
A program called “Rother J” was the first computer virus to appear “in the wild” — that is, outside the single computer or lab where it was created. Written in 1981 by Richard Skrenta, it attached itself to the Apple DOS 3.3 operating system and spread via floppy disk. This virus was created as a practical joke when Richard Skrenta was still in high school. It was injected in a game on a floppy disk. On its 50th use the Elk Cloner virus would be activated, infecting the computer and displaying a short poem beginning “Elk Cloner: The program with a personality.”
Guide to Building your own Computer
These days, every component can be bought separately and put together at home to create a bespoke system that reflects your specific requirements. For example, you might require a larger monitor than is standard with the model you want, you might need more memory, greater processing speed or any number of other elements that can’t be bought in one tidy package.
The motherboard is the heart and soul of any computer and this should really be your first consideration when you start thinking about putting together your own system. With so many options now available, it really is possible to create a computer from scratch that works more specifically for gaming, tech, or other uses that an out-of-the-box computer might not be designed for.
Motherboards, like all other computer components, are available in all manner of specifications and to suit every budget. You don’t need to spend a fortune to buy a good quality motherboard that will combine with other elements to create a high spec computer that’s been designed with your needs in mind. In fact, some of the cheaper models are more than adequate to create exactly the system that you need to expert gaming or high-level technological work. Having said that, the motherboard is the heart of your computer and, if you can afford to spend a little more, you will reap the rewards in the long term.
If you need your motherboard to support graphics card then this will obviously have an impact on your final decision. You will also need to consider the speed of the processor and it’s really up to you whether you decide on the processor or the motherboard first – just make sure that they’re compatible. If you need a number of different USB ports you should also check this out when choosing your motherboard. Although most of them support numerous USBs these days, it’s always best to make sure. The same goes for firewire: people often assume that this comes as standards but that’s by no means the case. It’s a good idea to have a list of requirements that you can then cross-reference against each motherboard before making your final decision.
Personalize your computer that caters their requirements best with genuine computer components
Regardless of significant advancement in computer and laptops there are many who are not pleased with prefixed computer models. Today most computers come with plentiful peripherals and are flooded with tons of features. However different people have different requirements and hence they might prefer assembling their own computer with computer components according to their choice. For example, game lovers and people associated with graphics and animations, they require bigger graphic card whereas the regular computer users need more RAM power. This is why many prefer buying computer hardware components individually and assembling their computer to cater to their requirements best.
Another reason why people prefer building their own computer is that it keeps the cost low compared to buying branded computer from local stores. You can buy branded computer hardware and get the same performance and durability from personally built computer without paying extravagant charges. You can install you own operating system. You can have computer hardware components required as per your preference and save considerable money through it. In brief, while assembling computer at home, you will pay only for what you need. You can exclude all those programs and unwanted hardware that manufacturers include but you actually never use them.
Other than all those monetary benefits, assembling computer allows you the leverage to actually personalize your computer. You can customize it the way you want and give it the desired finishing. If you are looking at computer just for some general purpose, you can get your PC done with minimum computer hardware like RAM, Hard disk, CD-Rom, etc. Meanwhile, the most important aspects of the entire process are to buy computer components that are authentic, branded and durable.
Genuine computer components are easily and cheaply accessible from virtual stores. Shopping from correct dealers will enable you to save sufficient money and to Buy Computer Hard Drive and Buy Computer RAM of your preferred brand. Such dealers possess vast stock of reputable brands computer components and offer at affordable prices. You just have to do slight research to locate an authentic and authorized dealer to avail warranty/guarantee when you buy Computer Parts from them. Along with buying computer parts, it is also important that you must acquire basic knowledge about the computer assembling to ensure perfect execution. Computer building knowledge is easily accessible online and one can easily build up their own computer with genuine computer hardware by following step-by-step manual.
So whether you are looking to build your own computer or refurbishment or replacing some specific component, you should always look to buy Computer Hard Drive and other component from genuine dealers only. Along with offering genuine components, you will also find valuable information and assistance to aid you in selecting correct computer components. So, whether you are looking to Buy Computer RAM or buy compute monitor, you can simply log in a computer nearby and visit online store and place your order. Parts will be delivered to you within reasonable time with due safety.
Computer Freezes
Do you see a lot of messages like, “This program performed an illegal operation and will be shut down” ? Or do you find that your mouse often freezes and you have to reset your computer to regain control?
This is a very common complaint for many computer users. Why this happens can be due to a number of things. The most common causes of these troublesome problems will be covered here. They fall into the following general categories:
Hardware: Defective or mismatched components in your computer.
Aluminum Migration & ESD: Premature ageing and ?lectro Static Discharge?can make a computer very intermittent.
Operating System: Some versions of Windows have bugs that can cause these problems.
Drivers: Buggy or down-level drivers can cause many problems.
Software: Some programs have bugs in them that can cause these problems.
Memory Fragmentation: Do you often see the message, “System is dangerously low in resources” If so you are probably suffering Memory Fragmentation.
CMOS Settings: Improper CMOS settings can cause many problems. Changing CMOS settings can also be used to help diagnose some hardware problems.
Loading Order: The order in which the software components of your computer are loaded into memory, at startup each day, can cause a multitude of odd problems.
A Combination of the above: Defects in any of the above may only show up under specific circumstances.
Hardware
These Illegal operations or freezes can, many times, be related to bad or intermittent hardware, or simply mismatched hardware. Mismatched hardware is common, even some of the large computer manufactures do insufficient analyses and testing when they select the components that make up their systems. Many components that make up a computer just don’t play well together. Some modems just don’t work well with specific video cards. Some sound cards are incompatible with certain main boards. The list goes on. Many manufactures only look at the cost of a given part, not its compatibility, thus they can often produce unstable computer systems.
Hardware can become defective. Mishandling the internal components of a computer can prematurely age them, which reduces their lifespan from decades to weeks or months. Many hardware failures are subtle and will not cause the computer to completely stop working, but will cause intermittent problems. Adding new internal components to a computer, especially by under-trained technicians, can cause static electricity damage to the other parts of a computer. Electro Static Discharge “ESD” is similar to when you walk across the floor touch a doorknob and receive a shock, but it’s a much smaller spark. An ESD created by a person just working on the inside of a computer is so small that we can’t even feel it, but it can cause great damage to the computer’s internal components.
Computed Tomography (CT) Systems Market to 2016 – The High Slice Segment to be the Key Revenue Generator ||| Market Research Report
Summary
GBI Research’s new report, “Computed Tomography (CT) Systems Market to 2016 – The High Slice Segment to be the Key Revenue Generator” provides key data, information and analysis on the global Computed Tomography (CT) Systems market. The report provides market landscape, competitive landscape and market trends information the Computed Tomography (CT) Systems market. The report provides comprehensive information on the key trends affecting the market, and key analytical content on the market dynamics. The report also reviews the competitive landscape and technology offerings.
This report is built using data and information sourced from proprietary databases, primary and secondary research and in-house analysis by GBI Research’s team of industry experts.
Scope
– Key geographies covered include the US, Canada, the UK, Germany, France, Italy, Spain, Japan, China, India, Australia, and Brazil.
– Key segments covered include Low Slice Computed Tomography, Mid Slice Computed Tomography, and High Slice Computed Tomography.
– Annualized market revenues data from 2002 to 2009, forecast forward for 7 years to 2016. Company shares data for 2009.
– Qualitative analysis of key market trends, market drivers, and restraints by each category within Computed Tomography (CT) Systems market.
– The report also covers information on the leading market players, the competitive landscape, and the leading pipeline products and technologies.
– Key players covered include GE Healthcare, Philips Healthcare, Siemens Healthcare, Toshiba Medical Systems, and Hitachi Medical.
Table of Contents :
1 Table of Contents 4
1.1 List of Tables 7
1.2 List of Figures 8
2 Introduction 10
2.1 GBI Research Guidance 10
3 Computed Tomography Systems 11
3.1 Overview 11
3.2 Advantages of Computed Tomography Imaging 11
3.3 Low Slice Computed Tomography 11
3.4 Mid Slice Computed Tomography 12
3.5 High slice Computed Tomography 12
4 Computed Tomography Systems: Global Market Characterization 13
4.1 Global Computed Tomography Systems Market, Revenue ($m), Historic, 2002–2009 13
4.2 Global Computed Tomography Systems Market, Volume (units), Historic, 2002–2009 14
4.3 Global Computed Tomography Systems Market, Revenue, Forecast ($m), 2009–2016 15
4.4 Global Computed Tomography Systems Market, Volume (units), Forecast 2009–2016 16
4.5 Global Computed Tomography Systems Market, Key Trends 17
4.5.1 Technology that Minimizes Radiation Dosage is Expected to find Increased Adoption 17
4.5.2 Technologies with Faster Scanning Time and Reduced Examination Time are finding Increasing Demand 17
4.5.3 Fusion Technology such as SPECT/CT is Expected to be the Key Technological Trend in the Future 18
4.5.4 Multi Detector Cardiac Imaging will Enhance the Potential of Computed Tomography Systems in Cardiovascular Diseases 18
4.5.5 Multi slice CT Systems are finding Increased Physician Adoption 19
4.6 Global Computed Tomography Systems, Market Dynamics 21
4.6.1 Market Drivers 21
4.6.2 Market Restraints 26
4.7 Computed Tomography Systems Market, Global, Company Share (%), 2009 28
5 Computed Tomography Systems Market: Country Analysis and Forecasts 29
5.1 Computed Tomography Systems Market, US, Revenue ($m), Historic, 2002–2009 29
5.2 Computed Tomography Systems Market, US, Volume (units), Historic, 2002–2009 30
5.3 Computed Tomography Systems Market, US, Revenue ($m), Forecast, 2009–2016 31
5.4 Computed Tomography Systems Market, US, Volume (units), Forecast, 2009–2016 32
5.5 Computed Tomography Systems Market, Canada, Revenue ($m), Historic, 2002–2009 33
5.6 Computed Tomography Systems Market, Canada, Volume (units), Historic, 2002–2009 34
5.7 Computed Tomography Systems Market, Canada, Revenue ($m), Forecast, 2009–2016 35
5.8 Computed Tomography Systems Market, Canada, Volume (units), Forecast, 2009–2016 36
5.9 Computed Tomography Systems Market, UK, Revenue ($m), Historic, 2002–2009 37
5.10 Computed Tomography Systems Market, UK, Volume (units), Historic, 2002–2009 38
5.11 Computed Tomography Systems Market, UK, Revenue ($m), Forecast, 2009–2016 39
5.12 Computed Tomography Systems Market, UK, Volume (units), Forecast, 2009–2016 40
5.13 Computed Tomography Systems Market, Germany, Revenue ($m), Historic, 2002–2009 41
5.14 Computed Tomography Systems Market, Germany, Volume (units), Historic, 2002–2009 42
5.15 Computed Tomography Systems Market, Germany, Revenue ($m), Forecast, 2009–2016 43
5.16 Computed Tomography Systems Market, Germany, Volume (units), Forecast, 2009–2016 44
5.17 Computed Tomography Systems Market, France, Revenue ($m), Historic, 2002–2009 45
5.18 Computed Tomography Systems Market, France, Volume (units), Historic, 2002–2009 46
5.19 Computed Tomography Systems Market, France, Revenue ($m), Forecast, 2009–2016 47
5.20 Computed Tomography Systems Market, France, Volume (units), Forecast, 2009–2016 48
5.21 Computed Tomography Systems Market, Italy, Revenue ($m), Historic, 2002–2009 49
5.22 Computed Tomography Systems Market, Italy, Volume (units), Historic, 2002–2009 50
5.23 Computed Tomography Systems Market, Italy, Revenue ($m), Forecast, 2009–2016 51
5.24 Computed Tomography Systems Market, Italy, Volume (units), Forecast, 2009–2016 52
5.25 Computed Tomography Systems Market, Spain, Revenue ($m), Historic, 2002–2009 53
5.26 Computed Tomography Systems Market, Spain, Volume (units), Historic, 2002–2009 54
5.27 Computed Tomography Systems Market, Spain, Revenue ($m), Forecast, 2009–2016 55
5.28 Computed Tomography Systems Market, Spain, Volume (units), Forecast, 2009–2016 56
5.29 Computed Tomography Systems Market, Japan, Revenue ($m), Historic, 2002–2009 57
5.30 Computed Tomography Systems Market, Japan, Volume (units), Historic, 2002–2009 58
5.31 Computed Tomography Systems Market, Japan, Revenue ($m), Forecast, 2009–2016 59
5.32 Computed Tomography Systems Market, Japan, Volume (units), Forecast, 2009–2016 60
5.33 Computed Tomography Systems Market, China, Revenue ($m), Historic, 2002–2009 61
5.34 Computed Tomography Systems Market, China, Volume (units), Historic, 2002–2009 62
5.35 Computed Tomography Systems Market, China, Revenue ($m), Forecast, 2009–2016 63
5.36 Computed Tomography Systems Market, China, Volume (units), Forecast, 2009–2016 64
5.37 Computed Tomography Systems Market, India, Revenue ($m), Historic, 2002–2009 65
5.38 Computed Tomography Systems Market, India, Volume, Historic, 2002–2009 66
5.39 Computed Tomography Systems Market, India, Revenue ($m), Forecast, 2009–2016 67
5.40 Computed Tomography Systems Market, India, Volume (units), Forecast, 2009–2016 68
5.41 Computed Tomography Systems Market, Australia, Revenue ($m), Historic, 2002–2009 69
5.42 Computed Tomography Systems Market, Australia, Volume (units), Historic, 2002–2009 70
5.43 Computed Tomography Systems Market, Australia, Revenue ($m), Forecast, 2009–2016 71
5.44 Computed Tomography Systems Market, Australia, Volume (units), Forecast, 2009–2016 72
5.45 Computed Tomography Systems Market, Brazil, Revenue ($m), Historic, 2002–2009 73
5.46 Computed Tomography Systems Market, Brazil, Volume (units), Historic, 2002–2009 74
5.47 Computed Tomography Systems Market, Brazil, Revenue ($m), Forecast, 2009–2016 75
5.48 Computed Tomography Systems Market, Brazil, Volume (units), Forecast, 2009–2016 76
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How The Computer Criminals Control Information – Types of Computer Crime
As computer-related crimes become more prevalent, understanding the types of computer-related crimes provides law enforcement an insight for investigative strategies.
The first insight is knowing the types of computer crimes.
Computer as the Target
This computer crime includes theft of intellectual property. The offender accesses the operating program under the guise of the system’s manager. The intruder accesses the contents of computer files in the system through the trap door that permits access to systems should there be a human or technological problem.
Here, the offender uses the computer to obtain information or to damage operating programs while committing the following computer crimes:
* Theft of marketing information, like customer lists, pricing data, or marketing plans
* Blackmail based on information gained from computerized files, like the medical information, personal history, or sexual preference
* Sabotage of intellectual property, marketing, pricing, or personnel data
* Sabotage of operating systems and programs with the intent to impede a business or create chaos in a business operations
* Unlawful access to criminal justice and other government records
* Changing a criminal history, modifying want and warrant information
* Creating a driver’s license, passport, or another document for false identification
* Changing tax records or gaining access to intelligence files
* Techno-vandalism through unauthorized access to damage files or programs
* Techno-trespass violating the owner’s privacy as in criminal trespass
Computer as the Instrumentality of the Crime
Here, the processes of the computer facilitate the crime.
The computer criminal introduces a new code (programming instructions) to manipulate the computer’s analytical processes and for converting legitimate computer processes for the following illegitimate purposes:
* Fraudulent use of automated teller machine (ATM) cards and accounts
* Theft of money from accrual, conversion, or transfer accounts, credit card fraud, fraud from computer transactions like the stock transfers, sales, or billings and telecommunications fraud
* Billing charges to other customers through cellular phones
* Once they capture the computerized billing codes, the computer criminals program these codes into other cellular phones simply by hooking up the phone to a personal computer
* Using software originally developed by programmers in other countries they reprogram the signal chip in the cellular phone
* Share the same through underground computer bulletin board services (BBS)
COMPUTER VISION SYNDROME: AN UPDATE
COMPUTER VISION SYNDROME: AN UPDATE
1Pooja Bagdi*, 1Swati Rathore, 2Kamal Singh Rathore
1B.N. College of Pharmacy, Udaipur
2B.N. Girls College of Pharmacy, Udaipur-Raj.
+919828325713(M)
Vision is our most precious sense. Our eyes are in constant use every waking minute of every day. Vision disturbance is a silent enemy that only appears after a long period of continued stress.
INTRODUCTION
Computers have equalled the telephone is becoming the most indispensable piece of office equipment. Because computer use is such a high visually demanding task, vision problems and symptoms have become very common in today’s workplace. Most studies indicate that computer operators, who view their Video Display Terminals (VDTs), report more eye-related problems than non-VDT office workers. A number of investigators have indicated that visual symptoms occur in 75-90% of VDT workers. In contrast to the popular conception regarding carpal tunnel syndrome, a study released by NIOSH showed that only 22% of VDT worker. A survey of optometrists indicated that 10 million eye examinations are annually given in this country primarily because of visual problems at VDTs. This study delineated the series of symptoms which eventually became known as Computer Vision Syndrome (CVS). Computer Vision Syndrome describes a group of eye and vision-related problems that result from prolonged computer use. Many individuals experience eye discomfort and vision problems when viewing a computer screen for extended periods. The level of discomfort appears to increase with the amount of computer use.
CAUSES OF COMPUTER VISION SYNDROME
Viewing a computer screen often makes the eyes work harder. As a result, the unique characteristics and high visual demands of computer viewing make many individuals susceptible to the development of vision-related symptoms. Uncorrected vision problems can increase the severity of Computer Vision Syndrome symptoms. Viewing a computer screen is different than reading a printed page. Often the letters on the computer screen are not as precise or sharply defined, the level of contrast of the letters to the background is reduced, and the presence of glare and reflections on the screen may make viewing difficult.
Viewing distances and angles used for computer work are also often different from those commonly used for other reading or writing tasks. As a result, the eye focusing and eye movement requirements for computer viewing can place additional demands on the visual system. In addition, the presence of even minor vision problems can often significantly affect comfort and performance at a computer. Uncorrected or under corrected vision problems can be major contributing factors to computer-related eyestrain. In most cases, symptoms of CVS occur because the visual demands of the task exceed the visual abilities of the individual to comfortably perform them. At greatest risk for developing CVS are those persons who spend two or more continuous hours at a computer every day.
SYMPTOMS OF COMPUTER VISION SYNDROME
• eye strain
• headaches
• blurred vision
• dry eyes
• neck and shoulder pain
These symptoms may be caused by:
• poor lighting
• glare on the computer screen
• improper viewing distances
• poor seating posture
• uncorrected vision problems
• a combination of these factors
The extent to which individuals experience visual symptoms often depends on the level of their visual abilities and the amount of time spent looking at the computer screen. Uncorrected vision problems like farsightedness and astigmatism, inadequate eye focusing or eye coordination abilities, and aging changes of the eyes, such as presbyopia, can all contribute to the development of visual symptoms when using a computer.
Many of the visual symptoms experienced by computer users are only temporary and will decline after stopping computer work. However, some individuals may experience continued reduced visual abilities, such as blurred distance vision, even after stopping work at a computer. If nothing is done to address the cause of the problem, the symptoms will continue to recur and perhaps worsen with future computer use.
Prevention or reduction of the vision problems associated with Computer Vision Syndrome involves taking steps to control lighting and glare on the computer screen, establishing proper working distances and posture for computer viewing, and assuring that even minor vision problems are properly corrected.
PATHOPHYSIOLOGY OF COMPUTER VISION SYNDROME
CVS is caused by decreased blinking reflex while working long hours focusing on computer screens. The normal blink rate in human eyes is 16–20 per minute. Studies have shown that the blink rate decreases to as low as 6–8 blinks/minute for persons working on the computer screen. This leads to dry eyes. Also, the near focusing effort required for such long hours puts strain on ciliary muscles of the eye. This induces symptoms of asthenopia and leads to a feeling of tiredness in the eyes after long hours of work. Some patients present with inability to properly focus on near objects after a short duration. This can be seen in people aged around 30–40 years of age, leading to a decrease in the accommodative focusing mechanisms of the eye. This can be a setting for early presbyopia.
DIAGNOSIS OF COMPUTER VISION SYNDROME
Computer Vision Syndrome can be diagnosed through a comprehensive eye examination. Testing, with special emphasis on visual requirements at the computer working distance, may include:
Patient history to determine any symptoms the patient is experiencing and the presence of any general health problems, medications taken, or environmental factors that may be contributing to the symptoms related to computer use. Visual acuity measurements to assess the extent to which vision may be affected. A refraction to determine the appropriate lens power needed to compensate for any refractive errors (nearsightedness, farsightedness or astigmatism).
Testing how the eyes focus, move and work together. In order to obtain a clear, single image of what is being viewed, the eyes must effectively change focus, move and work in unison. This testing will look for problems that keep your eyes from focusing effectively or make in this testing may be done without the use of eye drops to determine how the eyes respond under normal seeing conditions. In some cases, such as when some of the eyes’ focusing power may be hidden, eye drops may be used. They temporarily keep the eyes from changing focus while testing is done. Using the information obtained from these tests, along with results of other tests, your optometrist can determine if you have Computer Vision Syndrome and advise you on treatment options.
Therapy
Dry eye is a major symptom that is targeted in the therapy of CVS. The use of over-the-counter artificial-tear solutions can reduce the effects of dry eye in CVS. Asthenopic symptoms in the eye are responsible for much of the morbidity in CVS. Proper rest to the eye and its muscles is recommended to relieve the associated eye strain. Various catch-phrases have been used to spread awareness about giving rest to the eyes while working on computers. A routinely recommended approach is to consciously blink the eyes every now and then (this helps replenish the tear film) and to look out the window to a distant object or to the sky—doing so provides rest to the ciliary muscles. One of the catch phrases is the “20-20-20 rule”: every 20 minutes, focus the eyes on an object 20 feet (6 meters) away for 20 seconds. This basically gives a convenient distance and timeframe for a person to follow the advice from the optometrist and ophthalmologist. Otherwise, the patient is advised to close his/her eyes (which have a similar effect) for 20 seconds, at least every half hour.
Decreased focusing capability is mitigated by wearing a small plus-powered (+1.00 to +1.50) over-the-counter pair of eyeglasses. Wearing these eyeglasses helps such patients regain their ability to focus on near objects. People who are engaged in other occupations—such as tailors engaged in embroidery—can experience similar symptoms and can be helped by these glasses.
TREATMENT OF COMPUTER VISION SYNDROME
Solutions to computer-related vision problems are varied. However, CVS can usually be alleviated by obtaining regular eye care and making changes in how you view the computer screen.
Eye Care
In some cases, individuals who do not require the use of eyeglasses for other daily activities may benefit from glasses prescribed specifically for computer use. In addition, persons already wearing glasses may find their current prescription does not provide optimal vision for viewing a computer. Eyeglasses or contact lenses prescribed for general use may not be adequate for computer work. Lenses prescribed to meet the unique visual demands of computer viewing may be needed. Special lens designs, lens powers or lens tints or coatings may help to maximize visual abilities and comfort.
Some computer users experience problems with eye focusing or eye coordination that can’t be adequately corrected with eyeglasses or contact lenses. A program of vision therapy may be needed to treat these specific problems. Vision therapy, also called visual training, is a structured program of visual activities prescribed to improve visual abilities. It trains the eyes and brain to work together more effectively. These eye exercises help remediate deficiencies in eye movement, eye focusing and eye teaming and reinforce the eye-brain connection. Treatment may include office-based as well as home training procedures.
Viewing the Computer
Some important factors in preventing or reducing the symptoms of CVS have to do with the computer and how it is used. This includes lighting conditions, chair comfort, location of reference materials, position of the monitor, and the use of rest breaks.
Location of computer screen - Most people find it more comfortable to view a computer when the eyes are looking downward. Optimally, the computer screen should be 15 to 20 degrees below eye level (about 4 or 5 inches) as measured from the center of the screen and 20 to 28 inches from the eyes.
Reference materials – These materials should be located above the keyboard and below the monitor. If this is not possible, a document holder can be used beside the monitor. The goal is to position the documents so you do not need to move your head to look from the document to the screen.
Lighting - Position the computer screen to avoid glare, particularly from overhead lighting or windows. Use blinds or drapes on windows and replace the light bulbs in desk lamps with bulbs of lower wattage.
Anti-glare screens - If there is no way to minimize glare from light sources, consider using a screen glare filter. These filters decrease the amount of light reflected from the screen.
Seating position - Chairs should be comfortably padded and conform to the body. Chair height should be adjusted so your feet rest flat on the floor. If your chair has arms, they should be adjusted to provide arm support while you are typing. Your wrists shouldn’t rest on the keyboard when typing.
Rest breaks – To prevent eyestrain, try to rest your eyes when using the computer for long periods. Rest your eyes for 15 minutes after two hours of continuous computer use. Also, for every 20 minutes of computer viewing, look into the distance for 20 seconds to allow your eyes a chance to refocus.
Blinking - To minimize your chances of developing dry eye when using a computer, make an effort to blink frequently. Blinking keeps the front surface of your eye moist.
Regular eye examinations and proper viewing habits can help to prevent or reduce the development of the symptoms associated with Computer Vision Syndrome.
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Reader, Bhupal Nobles’ Girls’ College of Pharmacy, Udaipur-Raj.313002 INDIA Email: kamalsrathore@yahoo.com kamalsrathore@gmail.com Mobile: +919828325713
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Hidden costs of purchasing a computer
Most of us when we buy a computer, we only look at that sticker price. We see the price tag and think, “I can afford that.” Then we just shop for our computer just looking for the cheapest computer that can do what we want it do. We don’t even consider that there might be hidden costs that we are not addressing. By revealing discussing the costs of upgrades, repairs, and electricity, I hope you can understand just a little bit more when you purchase your next computer.
As you look at a computer purchase, you may evaluate Ghz, RAM, and HDD size. We rarely evaluate what it will cost to upgrade the computer, maintain, or run the computer. Perhaps you are buying the computer for a corporation and you will replace the computer in a few years. In this scenario, as long as the computer meets the minimum requirements, then there is probably no need to worry about upgrades and an extended warranty might cover the cost of parts and service. For the rest of us, it might be wise to know the more of the full cost of our purchase before you pay out our hard earned money.
Upgrades
There is no reason to panic. Even in a couple years the following should still be true, as it has held true for many years: the cheapest way to update your computer is often to upgrade the computer instead of replacing it. You can buy upgrades upfront or years down the road.
Purchasing upgrades upfront can be a great way to get more out of your computer purchase, and you will usually be pleased with a computer that can do more. Computer manufacturers and system builders know this. Even at Burke Computers, we build our computers with some potential for upgrade and will gladly sell you what upgrades we have access to.
This is the first place I want advise you to be wary. That cheap computer could easily end up costing significantly more. Sometimes buying the more expensive model upfront could give you all the same features and have a smaller price tag. To test this, I visited a manufacturer’s website and started with their $299 computer (as a system builder, I cannot even purchase the parts I trust for that cheap). At each step of the process, the manufacturer usually marked a recommended upgrade. This wasn’t always the top available upgrade. By only clicking the manufacturer’s recommended upgrades, not only did the price quickly jump into the ballpark of the computer builds I sell, I also noted that they had another model computer with almost of these features for a cheaper price. Of course selecting the better computer unlocked a whole new set of recommended upgrades, repeating the cycle.
