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Subgoal induction

A proof method, subgoal induction, is presented as an alternative or supplement to the commonly used inductive assertion method. Its major virtue is that it can often be used to prove a loop's correctness directly from its input …

The editing of picture segmentations using local analysis of graphs

A major problem in picture processing is the elimination of the large number of spurious regions that result from an initial segmentation by region growing techniques. Such regions have been eliminated either on the basis of  …

Studies in machine cognition using the game of poker

A progress report is presented of on-going research efforts concerning human decision making under uncertainty and risk and human problem solving and learning processes on the one hand, and machine learning, large scale programming …

Analysis of design alternatives for virtual memory indexes

A class of index structures for use in a virtual memory environment is described. Design alternatives within this class of index structures are analyzed. These alternatives include a choice of search strategy, whether or not  …

The stage hypothesis and the s-curve: some contradictory evidence

This paper presents the results of a study testing the s-shaped budget curve of Nolan's stage model of computer development in an organization. Research on the data processing budgets of California counties fails to support the …

Approximating block accesses in database organizations

When data records are grouped into blocks in secondary storage, it is frequently necessary to estimate the number of blocks XD accessed for a given query. In a recent paper [1], Cardenas gave the expression XD = m(1 - (1 - 1/ …

Remark on uniform insertion in structured data structures

In a recent paper, Shneiderman and Scheuermann [1] have defined an interesting operation, called uniform insertion, whereby a (linked) data structure G2 can be embedded within another structure G1 in such a way that each data …

Comment on weighted increment linear search for scatter tables

I would like to comment on an article by Fabrizio Luccio [1] which discusses weighted increment linear search for scatter tables.

Sorting on a mesh-connected parallel computer

Two algorithms are presented for sorting n2 elements on an n × n mesh-connected processor array that require O (n) routing and comparison steps. The best previous algoritmhm takes time O(n log n). The algorithms of this paper …

Proof techniques for hierarchically structured programs

A method for describing and structuring programs that simplifies proofs of their correctness is presented. The method formally represents a program in terms of levels of abstraction, each level of which can be described by a  …

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