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lesson 29. Computers and the Individual . This lesson includes the following sections: Ergonomics and Health Issues Privacy Issues . Ergonomics and Health Issues . Ergonomics Defined Repetitive Stress Injuries Avoiding Repetitive Stress Injuries Eyestrain Electromagnetic Fields.
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lesson 29 • Computers and the Individual
This lesson includes the following sections: • Ergonomics and Health Issues • Privacy Issues
Ergonomics and Health Issues • Ergonomics Defined • Repetitive Stress Injuries • Avoiding Repetitive Stress Injuries • Eyestrain • Electromagnetic Fields
Ergonomics and Health Issues - Ergonomics Defined • Ergonomics is the study of the physical relationship between people and their tools – such as computers. • Extended or improper computer use may result in a number of ailments, such as: • Repetitive injuries • Carpal tunnel syndrome • Eyestrain • Exposure to electromagnetic fields
Ergonomics and Health Issues - Repetitive Stress Injuries • Repetitive stress injuries (RSIs) result from using the body continuously in ways it was not designed to work. • RSIs have appeared in office workers who spend a lot of time using the computer keyboard and mouse. • Carpal tunnel syndrome is a common type of repetitive stress injury, which may be caused by extended or improper use of a computer keyboard.
Ergonomics and Health Issues - Avoiding Repetitive Stress Injuries • One of the easiest ways to avoid RSIs is to use ergonomically correct furniture, including an ergonomically designed chair and keyboard. • An ergonomically correct chair features adjustable height, lower-back support, and armrests. It should allow you to type with your forearms parallel to the floor. • An ergonomically correct keyboard is designed to allow the hands to rest in a natural, comfortable position so you can type without overreaching or getting fatigued.
Lower back support Armrests Adjustable height Angles place hands in a natural position
Ergonomics and Health Issues - Eyestrain • Many computer users find their vision deteriorating after a while. This is caused by using the PC too long, poor positioning, or other factors. • To avoid eyestrain, don't stare at the screen too long, place the monitor from 2 to 2 ½ feet away, avoid glare, and keep the screen clean. • Use a monitor that holds a steady image without flickering. Look for a dot pitch no greater than .28 mm and a refresh rate of at least 72 Hz.
Ergonomics and Health Issues - Electromagnetic Fields • Electromagnetic fields (EMFs) occur during the generation, transmission, and use of low-frequency electrical power. Some people are concerned that EMFs are linked to cancer. • To reduce your risks from EMF exposure: • Take frequent breaks away from the computer. • Sit at arm's length from the system unit and monitor. • Use a flat-panel display (which does not produce EMFs).
Privacy Issues • Junk Faxes and E-Mail • Beating Spammers at Their Own Game • Privacy Issues Facing Corporate Computer Users
Privacy Issues - Junk Faxes and E-Mail • Junk faxes are unsolicited messages received from unnamed senders. Because they consume the recipient's resources, junk faxes have been outlawed. • Junk e-mail (spam) is any uninvited e-mail message, but spam usually is commercial in nature and is delivered to many users at one time. • Using a technique called spoofing, the spammer sends messages but hides his or her identity so the recipients cannot respond.
Privacy Issues – Beating Spammers at Their Own Game • Spam can cost businesses due to lost productivity. It can be annoying to individual users who must deal with junk messages. • One way to fight spammers is to read your ISP's appropriate use policy and to report spam to your ISP and to the sender's ISP, if possible. • You can also block messages from certain senders and domains, and use spam-blocking software provided by your ISP or a third party. • You can reduce junk mail by not adding your name to mailing lists, and by making sure your credit records do not fall into the wrong hands.
Privacy Issues - Privacy Issues & Corporate Computer Users A business owns its computer systems and the data they contain. Businesses are entitled to restrict the use of their systems, to inspect them, and to block employees from any or all services. Businesses commonly monitor the use of their systems to: • Protect trade secrets. • Prevent the distribution of libelous messages. • Prevent users from downloading inappropriate materials. • Ensure that resources are not wasted.
lesson 29 review • Define ergonomics and list four health risks related to computer use. • Define spamming and spoofing and explain how they affect computer users. • Name three normal activities that result in a threat to personal privacy. • List four reasons why a business may monitor employees' use of its systems.
Project due Jan. 24 • Please use PC-cillin from Trend Micro to catch a virus, put it on a disk, and hand in the disk. • Please write a detailed report on that virus about its name, creator, working mechanism, the problem it causes, ..., and so on.