computer-assisted instruction

Use of instructional material presented by a computer. Since the advent of microcomputers in the 1970s, computer use in schools has become widespread, from primary schools through the university level and in some preschool programs. Instructional computers either present information or fill a tutorial role, testing the student for comprehension. By providing one-on-one interaction and producing immediate responses to input answers, computers allow students to demonstrate mastery and learn new material at their own pace. A disadvantage is that computerized instruction cannot extend the lesson beyond the limits of the programming.

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When the knife is in the closed position, the blade is held in place by means of 1 or 2 torsion bars. As the user applies manual pressure to the thumbstud to open the knife, a mechanism such as a torsion bar moves along a track in the liner and rotates the blade into the open position.

Although commonly confused with switchblade knives, there is a difference. While a switchblade can be opened usually with the push of a button, the user of an assisted-opening knife must apply some pressure to the blade at the thumb stud or flipper.

Because the blade does not open by the push of a button or force of gravity, the assisted opening mechanism is normally not considered a switchblade. Once the knife has been opened about one-quarter of the way (45°), the mechanism opens the knife the rest of the way.

The side-opening switchblade differs from the assisted-opening knife - an assisted-opening knife is a knife that is opened partway by the user before a spring takes over and propels the blade open. Easily used and quickly opened with either hand, they are similar to switchblades, but have one main difference. While a switchblade can be opened, usually with the push of a button, the user of a spring-assisted knife must open the blade partway themselves with a thumb stud and the mechanism does the rest. Because the user's hands are free from the blade during opening they are far safer than a traditional knife where the user's hand must come into contact with the blade, and easier to operate (especially left handed) than many of the popular easy-open knife designs. The simplicity and rapidity of assisted-opening knives have raised questions about their legality, but they remain legal at this time.

Other names for assisted-opening knife are: A/O Knife, Torsion Assist Knife, Assisted Knife, Spring Assist Knife, Spring Assisted Knife, Quick Release, Quick Draw, Alternative Automatic and the Semi-Auto.

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