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151.
Summary The nonlinear CCSDTQ equations are written in a fully linearized form, via the introduction of computationally convenient intermediates. An efficient formulation of the coupled cluster method is proposed. Due to a recursive method for the calculation of intermediates, all computational steps involve the multiplication of an intermediate with aT vertex. This property makes it possible to express the CC equations exclusively in terms of matrix products which can be directly transformed into a highly vectorized program.This work has been supported by the U.S. Air Force Office of Scientific Research, Grant No. 90-0079 相似文献
152.
Charles Audet Pierre Hansen Frédéric Messine 《Journal of Combinatorial Theory, Series A》2007,114(1):135-150
The convex octagon with unit diameter and maximum perimeter is determined. This answers an open question dating from 1922. The proof uses geometric reasoning and an interval arithmetic based global optimization algorithm to solve a series of non-linear and non-convex programs involving trigonometric functions. 相似文献
153.
用集成电路制成程序控制器,示教板性能稳定,寿命长,效果好,操作方便.其主要部分由电源、时钟、逻辑电路、输出驱动器四部分组成. 相似文献
154.
In generalized fractional programming, one seeks to minimize the maximum of a finite number of ratios. Such programs are, in general, nonconvex and consequently are difficult to solve. Here, we consider a particular case in which the ratio is the quotient of a quadratic form and a positive concave function. The dual of such a problem is constructed and a numerical example is given. 相似文献
155.
O. L. Mangasarian 《Journal of Global Optimization》1995,6(2):153-161
The nonmonotone linear complementarity problem (LCP) is formulated as a bilinear program with separable constraints and an objective function that minimizes a natural error residual for the LCP. A linear-programming-based algorithm applied to the bilinear program terminates in a finite number of steps at a solution or stationary point of the problem. The bilinear algorithm solved 80 consecutive cases of the LCP formulation of the knapsack feasibility problem ranging in size between 10 and 3000, with almost constant average number of major iterations equal to four.This material is based on research supported by Air Force Office of Scientific Research Grant F49620-94-1-0036 and National Science Foundation Grants CCR-9322479 and CDA-9024618. 相似文献
156.
Roman Dmytryshyn Andrzej Kubaszek 《Analog Integrated Circuits and Signal Processing》2002,31(2):147-159
In this paper a concept of multimethodical program and a classification of Sequence of Expressions (SoE) for analog circuit analysis are discussed. It is shown that the proper selection of circuit analysis method as well as method of SoE generation enables the minimization of arithmetic operations during repetitive frequency and transient analysis of analog circuits. 相似文献
157.
Tim Van Voorhis 《Journal of Global Optimization》2002,24(3):349-370
Convex relaxations can be used to obtain lower bounds on the optimal objective function value of nonconvex quadratically constrained quadratic programs. However, for some problems, significantly better bounds can be obtained by minimizing the restricted Lagrangian function for a given estimate of the Lagrange multipliers. The difficulty in utilizing Lagrangian duality within a global optimization context is that the restricted Lagrangian is often nonconvex. Minimizing a convex underestimate of the restricted Lagrangian overcomes this difficulty and facilitates the use of Lagrangian duality within a global optimization framework. A branch-and-bound algorithm is presented that relies on these Lagrangian underestimates to provide lower bounds and on the interval Newton method to facilitate convergence in the neighborhood of the global solution. Computational results show that the algorithm compares favorably to the Reformulation–Linearization Technique for problems with a favorable structure. 相似文献
158.
基于ISP芯片的数字编码波形发生器设计 总被引:1,自引:0,他引:1
介绍了一种可程控的编码波形发生器,并重点讨论了用Synplicity的VHDL和在系统可编程逻辑器件ispLSI5KVE的实现方法. 相似文献
159.
Akiko Takeda Katsuki Fujisawa Yusuke Fukaya Masakazu Kojima 《Journal of Global Optimization》2002,24(2):237-260
As computing resources continue to improve, global solutions for larger size quadrically constrained optimization problems become more achievable. In this paper, we focus on larger size problems and get accurate bounds for optimal values of such problems with the successive use of SDP relaxations on a parallel computing system called Ninf (Network-based Information Library for high performance computing). 相似文献
160.
浅谈TMS320C6000中断程序的实现方法 总被引:3,自引:0,他引:3
主要讨论中断服务程序在TMS320C6000 DSP中的几种用C语言来实现的方法。 相似文献