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Although not well known, the University of Toronto had a very early computer-development program and in 1952 was one of the first few institutions with an operable computer in North America. This article describes the university's initial attempt to build the UTEC computer and how it acquired the pioneering Ferut machine 相似文献
104.
Conclusion In the optimization problem [f
0(x)│hi(x)<-0,i=1,…,l] relaxation of the functionf
0(x)+Nh+(x) does not produce, as we know [6, 7], αk=1 in Newton's method with the auxiliary problem (5), (6), whereF(x)=f
0′(x). For this reason, Newton type methods based on relaxation off
0(x)+Nh+(x) are not superlinearly convergent (so-called Maratos effect). The results of this article indicate that if (F(x)=f
0′(x), then replacement of the initial optimization problem with a larger equivalent problem (7) eliminates the Maratos effect
in the proposed quasi-Newton method. This result is mainly of theoretical interest, because Newton type optimization methods
in the space of the variablesx ∈R
n are less complex. However to the best of our knowledge, the difficulties with nonlocal convergence arising in these methods
(choice of parameters, etc.) have not been fully resolved [10, 11]. The discussion of these difficulties and comparison with
the proposed method fall outside the scope of the present article, which focuses on solution of variational inequalities (1),
(2) for the general caseF′(x)≠F′
T(x).
Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 78–91, November–December, 1994. 相似文献
105.
First break picking is a pattern recognition problem in seismic signal processing, one that requires much human effort and is difficult to automate. The authors' goal is to reduce the manual effort in the picking process and accurately perform the picking. Feedforward neural network first break pickers have been developed using backpropagation training algorithms applied either to an encoded version of the raw data or to derived seismic attributes which are extracted from the raw data. The authors summarize a study in which they applied a backpropagation fuzzy logic system (BPFLS) to first break picking. The authors use derived seismic attributes as features, and take lateral variations into account by using the distance to a piecewise linear guiding function as a new feature. Experimental results indicate that the BPFLS achieves about the same picking accuracy as a feedforward neural network that is also trained using a backpropagation algorithm; however, the BPFLS is trained in a much shorter time, because there is a systematic way in which the initial parameters of the BPFLS can be chosen, versus the random way in which the weights of the neural network are chosen 相似文献
106.
Robotica is a computer aided design package for robotic manipulators developed in the Coordinated Science Laboratory at the University of Illinois at Urbana-Champaign. It encapsulates over 30 functions into a Mathematica package allowing efficient symbolic and numeric calculation of kinematic and dynamic equations for multi-degree-of-freedom manipulators. An X-Windows front end that utilizes the interprocess communication features of Mathematica 2.1 has also been created for ease of use. This paper describes the most important features of the package and how they are used 相似文献
107.
F. Cioffi E. M. Cohen Richard Badick 《Drug development and industrial pharmacy》1993,19(14):1741-1746
Carstensen and Rhodes1 have suggested that when, in stability programs, assays cannot be performed immediately after the protocol-designated storage time, then freezing them until such a time when assays can be performed would be a reasonable manner to retain the protocol schedule. They caution, however, that such a procedure may not be valid for dissolution data. The article to follow deals with real-time data showing that such a process is feasible for Nalidixic Acid tablets (and presumably for other tablets as well), and that, furthermore, the dissolution pattern would seem to be “frozen” as well. 相似文献
108.
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110.
M. Ronen 《Journal of Computer Assisted Learning》1995,11(3):141-156
Abstract This article presents a study of a large scale incorporation of one data acquisitionsystem into physics teaching in Israel. By 1994 about 30% of the schools throughout the country used the V-scope, a 3-D multibody motion tracing system, in their lab programme. The views and reactions of post-training teachers, experienced teachers and students on various aspects of using the system are described, analysed and compared. 相似文献