Computing Applications
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Predicative programming Part II
Part I of this two-part paper presented a new semantics of programs. Each program is considered to be a predicate, in a restricted notation, that specifies the observable behavior of a computer executing the program. We considered a variety of notations, including assignment, composition (semicolon), deterministic choice (if), nondeterministic choice, definition (nonrecursive and recursive), and variable declaration. We did not consider any input or output notations, or concurrency; that is the subject of Part II. We assume the reader is familiar with Part I, so that we can build on ideas presented there.
Online help systems: a conspectus
Users of computer systems are now accustomed to the convenience of online help systems and generally demand these amenities in the computers they buy. However, recent studies as to the efficacy of certain types of assistance for certain classes of users raise important questions for designers.
The coordinated use of five performance evaluation methodologies
Information system design can be influenced and ultimate performance parameters accurately forecast through the coordinated use of five performance analysis tools. The complementary methodology is used to first predict and then validate system performance throughout its life cycle.
Is Ada too big? A designer answers the critics
Many have criticized the Department of Defense's new computer language, Ada, saying it is too large, too complicated, or too difficult to use. Are they right? And are there some simplifications that could be made to Ada without destroying its usefulness?
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