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861.
A.M. Morshedi 《Journal of The Franklin Institute》1980,310(2):89-105
Optimum process operating conditions are often achieved by on-line computer programming. A general method has been developed which is capable of optimizing processes whose responses are corrupted by random error. The method is particularly useful for application to processes whose response functions contain sharp ridges. Application to ridge and non-ridge systems gives the same results in each case showing that the rate of convergence of the search is totally unaffected by the presence of a ridge. An accelarated gradient method is used which obtains its derivatives from a quadratic interpolation. The inability of the gradient method to move along a ridge is overcome by projecting a straight line through points on the ridge to obtain new starting points for a gradient search. Points on the ridge are located by finding the stationary point of the polynomial which is constructed by regression through points found by the gradient search. The method is applied to several test functions known to the literature—a fast convergence rate is obtained for a wide range of noise levels. 相似文献
862.
863.
Linguistic influences on networks of professional communication and recognition among engineers at two Quebec universities were examined. It was hypothesized that chemists and engineers affiliated with the French medium University of Montreal and the Ecole Polytechnique would be less active in research and more likely to obtain scientific recognition locally and to feel professionally unrecognized outside Quebec compared to their colleagues at McGill University. The findings suggest that the localizing effects of using a medium of scientific training which is not the predominant language of international scientific communication and recognition (French) are ambiguous. Although chemists and engineers at the French medium institutions were less active researchers, their language of professional communication with other scientific communities was English and there was little sense of isolation.This research has been supported by grants from the Canadian Council and the Ecole Polytechnique of Montreal. The authors also wish to thank Miss Madeleine Palmer, Miss Daniella Quiniou and Miss Rosalba Casas for their help in data collection for this paper. 相似文献
864.
865.
Michael P. Jordan 《Instructional Science》1980,9(3):221-252
Linguistic analysis of short published reports leads to the presentation of an aigorithm that depicts the problem-solving process in terms of a series of evaluative questions. The work shows how reports enable us to define in detail the various stages of problem solving, and it shows that an understanding of these various stages enables us to recognise information structures in written texts; the writing of brief reports of high-priority information on which the whole thinking process is based is thus seen as a vital part of the problem-solving process. One report is analysed in detail to demonstrate the close relationship between information structures in the text and the real-life thought'action process it describes. There is discussion of how paragraphs, sentences and signals within the sentences enable the writer to communicate the information in a conceptual array that represents the actual thought/action process it describes. Educational implications for inter-sentential coherence, discourse analysis, and writing structures, and control of research through written reports are all discussed. 相似文献
866.
S.G. Tzafestas 《Journal of The Franklin Institute》1980,309(6):399-438
In this paper a variety of optimal control (OC) problems for distributed- parameter (DP) systems are approached using mathematical programming (MP). First, the principal DP models in current use are given, a variety of DP objective functions is provided, and the OC problems based on them are formulated. Second, these models and objective functions are converted in algebraic form, as required by MP, and the solution procedure of the OC problems via MP is outlined. Third, a representative set of nonlinear programming results applied to DP systems is presented, and finally, a numvber of application examples is given. 相似文献
867.
868.
The case is considered in which, during the operation of an optimal control system, the optimizer, in addition to applying his usual control, may switch structures. Necessary and sufficient conditions are derived and emphasis is placed on the special characteristics of this problem. Continuous and discrete time set-ups are considered and the separation principle is shown not to hold for the linear quadratic case in the presence of noise. 相似文献
869.
870.
Mathematics has always played an important role in the education of engineers and production managers. At the present time, the importance of mathematics has increased significantly and it is quite natural that in universities around the world engineering students are taking courses in mathematics which constitute, as a rule, a significant portion of their programme. At the same time, however, the mathematical education of the engineer is far from ideal and its improvement deserves the closest scrutiny. The present article deals with several general aspects of this problem. 相似文献