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51.
We describe a binding environment for the AND and OR parallel execution of logic programs that is suitable for both shared and nonshared memory multiprocessors. The binding environment was designed with a view of rendering a compiler using this binding environment machine independent. The binding environment is similar to closed environments proposed by J. Conery. However, unlike Conery's scheme, it supports OR and independent AND parallelism on both types of machines. The term representation, the algorithms for unification and the join algorithms for parallel AND branches are presented in this paper. We also detail the differences between our scheme and Conery's scheme. A compiler based on this binding environment has been implemented on a platform for machine independent parallel programming called the Chare Kernel 相似文献
52.
This paper proposes a system based on a parallel genetic algorithm with enhanced encoding and operational abilities. The system, used to evolve feedforward artificial neural networks, has been applied to two widely different problem areas: Boolean function learning and robot control. It is shown that the good results obtained in both cases are due to two factors: first, the enhanced exploration abilities provided by the search-space reducing evolution of both coding granularity and network topology, and, second, the enhanced exploitational abilities due to a recently proposed cooperative local optimizing genetic operator. 相似文献
53.
What is the implication for business when information technology (IT) changes in the workplace without a commensurate change in the composition of business programs educating tomorrow's employees? A survey of MBA graduates forms the basis of this article on the IT skills needed in the marketplace. 相似文献
54.
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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
56.
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58.
Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 95–112, March–April, 1994. 相似文献
59.
Sh. V. Gedevanishvili V. I. Yukhvid G. Sh. Oniashvili 《Journal of Engineering Physics and Thermophysics》1993,65(5):1134-1137
Use of inexpensive ore concentrates as initial components in SHS metallurgy [1–3] brings about some specific features in the process and the properties of the materials obtained. Ore reagents contain a considerable amount of impurities (Al2O3, SiO2, Fe2O3) that decrease the energetics of SHS systems and the temperature and the rate of combustion and create the limits of combustion and phase separation. In addition, the impurities participate in chemical reactions and enter the desired product. In many cases the presence of silicon, iron, and aluminum in a cast product does not prevent use of this product for practical purposes.Institute of Metallurgy, Academy of Sciences of the Republic of Georgia, Tbilisi. Institute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 5, pp. 613–616, November, 1993. 相似文献
60.