The past study of program synthesis has mainly concentrated on attempting to synthesis programs by duplicating human methods for constructing programs, such as top-down design. Here we do not attempt this process but ...
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The past study of program synthesis has mainly concentrated on attempting to synthesis programs by duplicating human methods for constructing programs, such as top-down design. Here we do not attempt this process but instead use a simple method that is based on sound software engineering practice. Knuth-Bendix completion is used in the synthesis process but without the need for the exhaustive completion of program axioms against each other. A software engineering framework is used to reduce the pairs of completed program axioms to the optimum for synthesising the required program. Examples of program synthesis are given and contrasted with an ad hoc method of synthesis.
Very high level languages (VHLL) and automatic program generators should allow significant reductions in the time and skill required for software development. The feasibility of management professionals directly spec...
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Very high level languages (VHLL) and automatic program generators should allow significant reductions in the time and skill required for software development. The feasibility of management professionals directly specifying, generating, and debugging software for management systems without assistance from programming professionals is examined. This is based on the hypothesis that this would be the preferred mode of development. In an experiment, an accounting student with limited background in computing used the MODEL VHLL and program generator to develop an accounting system through 3 stages: 1. development of a general ledger, 2. addition of an inventory accounting system, and 3. modification to allow current dollar asset valuation. The experiment allowed assessment of the time involved for development, modification, and maintenance of the system. Use of MODEL was found to result in substantial improvements in development productivity, partly due to its error detection and easy modification capabilities.
An approach for implementing a 'smart' interface to support a relational view of data is proposed. The basic idea is to employ automatic programming techniques so that the interface analyzes and efficiently re...
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An approach for implementing a 'smart' interface to support a relational view of data is proposed. The basic idea is to employ automatic programming techniques so that the interface analyzes and efficiently refines the high level query specification supplied by the user. A relational algebra interface, called SQUIRAL, which was designed using this approach, is described in detail. SQUIRAL seeks to minimize query response time and space utilization by: (1) performing global query optimization, (2) exploiting disjoint and pipelined concurrency, (3) coordinating sort orders in temporary relations, (4) employing directory analysis, and (5) maintaining locality in page references. Algorithms for implementing the operators of E. F. Codd's relational algebra are presented, and a methodology for composing them to optimize the performance of a particular user query is described. [ABSTRACT FROM AUTHOR]
SequenceL is a general-purpose functional programming language that exploits information hiding in language design, shielding the programmer from the need to know how the language is implemented.
SequenceL is a general-purpose functional programming language that exploits information hiding in language design, shielding the programmer from the need to know how the language is implemented.
A prototyping tool which facilitates the design of Java applets based on existing Java classes in the repository is developed and embedded into an eLearning platform. An input-output tree is proposed to graphically sh...
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A prototyping tool which facilitates the design of Java applets based on existing Java classes in the repository is developed and embedded into an eLearning platform. An input-output tree is proposed to graphically show the data flow from the input to output of a specific application. In the future, the possible direction of using such similar application as the proposed tool will assist the programmer to assemble the reusable software components from the repository, in which the source codes are generated automatically by means of automatic programming.
An attempt is made to prove that the arguments of both proponents and detractors of expert systems based on artificial intelligence (AI) are misleading in that, while there are many non-AI expert systems, the AI techn...
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An attempt is made to prove that the arguments of both proponents and detractors of expert systems based on artificial intelligence (AI) are misleading in that, while there are many non-AI expert systems, the AI techniques do offer something new and significant, but not what the proponents often claim. The traditional and AI approaches are reviewed and compared. The traditional procedure involves specification, coding, testing, reformulation, recoding, and exit; the AI procedure involves initial specification, interpretive testing, incremental reformulation, and coding. AI offers 3 advantages: 1. It improves the specification without programming. 2. It eases the task of perfecting the specification in other ways. 3. It aids the task of programming the application system. The advantages are significant even though the finished system need not use any AI techniques at all. The productivity advantages are the hidden truths behind the ''myth'' that symbolic reasoning programs are better than traditional ones.
Recent research has attempted to quantify the quality of a software design in terms of measurable properties. A weakness of this research is that it ignores the fact that software design involves the exploration of al...
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Recent research has attempted to quantify the quality of a software design in terms of measurable properties. A weakness of this research is that it ignores the fact that software design involves the exploration of alternative software architectures. An approach to software design selection is described which involves examining a design solution space. It relies on the formulation of the problem of selecting software designs in operational research terms. The paper concludes with a description of a software tool based on the approach.
In order to simplify the calibration of mass spectra, a mass marker has been designed for the AEI mass spectrometer MS2H which, with slight modifications, can be applied to any other magnetically scanned spectrometer....
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In order to simplify the calibration of mass spectra, a mass marker has been designed for the AEI mass spectrometer MS2H which, with slight modifications, can be applied to any other magnetically scanned spectrometer. During the scanning of the spectrometer, the apparatus operates the marker pen of the recorder so that calibration markings are registered during recording of the spectrum. The marker is based on accurate determination of the current through the deflection magnet which is used for the magnetic scanning in the spectrometer. The influence of the hysteresis effect is eliminated by automatic programming of the magnet current before each measurement. When the marker is used with an AEI mass spectrometer MS2H, spectra can be calibrated at every fifth m/e in the range 60-535 m/e, provided the ion-accelerating voltage is 2000 v. The accuracy is to 0.3 m/e.
A unified model is established for a current-programmed converter, which is both a modification and an extension of familiar models. Inclusion of the sampling effect allows the presence of an additional pole omega(p) ...
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A unified model is established for a current-programmed converter, which is both a modification and an extension of familiar models. Inclusion of the sampling effect allows the presence of an additional pole omega(p) in the current-loop gain to be derived. The resulting final double-slope asymptote is fixed in position, and the crossover frequency cannot exceed half the switching frequency, A stability parameter, Q(s), determines the additional pole and describes the degree of peaking in the closed-loop transfer function. Experimental verification employs an analog signal injection technique.
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