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A storage and access manager for ill-structured data

Database management systems are powerful tools for processing large volumes of structured, or normalized, data. Much of the data to be stored in computer systems, however, differs from normalized data in both its logical uses and the storage structure required for its effective management. For instance, Van Rijsbergen (1979) distinguishes database retrieval from information retrieval (IR)—the retrieval of references to text—by comparing the following logical characteristics of IR systems to database management systems: IR Systems employ partial (vs. exact) matching; they are built on an underlying probabilistic (vs. deterministic) model; they classify information on a polythetic (vs. monothetic) basis, and queries are incompletely (vs. completely) specified. Similarly, other forms of relatively ill-structured data such as semantic networks [15]—which require property inheritance, and production rules—which must be joined in logical chains also differ in their logical use from normalized record structures.
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Computing Applications

Justification of printed music

There is increasing interest in the use of computer systems for editing and printing sheet music [3, 19]. Music processing lags far behind text processing because of the complexities of music notation. Most music published today is still laid out by hand; while computers may be used, decisions about music-symbol placement are made by people. Much research remains to be done into computational methods of encoding the myriad rules of music notation. Individual rules are not difficult to formulate; it is the complex interaction among rules which is difficult to describe and control. In this article we focus on one aspect of music notation: the horizontal spacing of music to produce a right- and left- justified result.
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Artificial Intelligence and Machine Learning

Economic analysis of microcomputer hardware

Economic analysis of the hardware characteristics of the personal computer segment of the microcomputer market indicates that the variables that most affect cost are the bundle of attributes offered by the micros. Interestingly, certain technological characteristics found to be important explanatory variables for cost in larger computers were not found to be significant for micros.
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Architecture and Hardware

Physical design equivalencies in database conversion

As relational technology becomes increasingly accepted in commercial data processing, conversion of some of the huge number of existing navigational databases to relational databases is inevitable. It is thus important to understand how to recognize physical design modifications and enhancements in the navigational databases and how to convert them to equivalent relational terms as applicable.
Computing Applications

A very fast substring search algorithm

This article describes a substring search algorithm that is faster than the Boyer-Moore algorithm. This algorithm does not depend on scanning the pattern string in any particular order. Three variations of the algorithm are given that use three different pattern scan orders. These include: (1) a “Quick Search” algorithm; (2) a “Maximal Shift” and (3) an “Optimal Mismatch” algorithm.
Systems and Networking

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