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201.
本文研究奇性两点狄利克雷问题,在f(t,x,y)≤α(t)g(x)+β(t)h(x)|y|ε,0<ε≤2情形下,得到了解的存在性定理,推广了Tineo(1992)的结果. 相似文献
202.
A new subgroup of3He rich solar flares is found on reanalysing the global data.3He/H ratio as a function of maximum proton flux at an energy of about 10 MeV shows a break-up of the data into two groups.
The first group follows the anticorrelation of3He/H ratio with the proton flux, as expected in the plasma process acceleration models. But the second group has a constant3He/H ratio as a function of maximum proton flux. This is not in conformity with the plasma process models. But this is expected
in models where the nuclear spallation reactions are responsible for the production of3He. It is also found that the same break-up into two distinct groups follows if one plots the location of the flares in the
solar disc. The first group is more or less confined to the west limb of the Sun, whereas the second group is more widely
spread out across the solar disk.
Visiting Professor, Tata Institute of Fundamental Research, Bombay, August–September, 1983. 相似文献
203.
Given a graphG=[V, E] with positive edge weights, the max-cut problem is to find a cut inG such that the sum of the weights of the edges of this cut is as large as possible. Letg(K) be the class of graphs whose longest odd cycle is not longer than2K+1, whereK is a nonnegative integer independent of the numbern of nodes ofG. We present an O(n
4K) algorithm for the max-cut problem for graphs ing(K). The algorithm is recursive and is based on some properties of longest and longest odd cycles of graphs.
This research was supported by National Science Foundation Grant ECS-8005350 to Cornell University. 相似文献
204.
Geometric Programming is extended to include convex quadratic functions. Generalized Geometric Programming is applied to this
class of programs to obtain a convex dual program. Machining economics problems fall into this class. Such problems are studied
by applying this duality to a nested set of three problems. One problem is zero degree of difficulty and the solution is obtained
by solving a simple system of equations. The inclusion of a constraint restricting the force on the tool to be less than or
equal to the breaking force provides a more realistic solution. This model is solved as a program with one degree of difficulty.
Finally the behavior of the machining cost per part is studied parametrically as a function of axial depth.
This research was supported by the Air Force Office of Scientific Research Grant AFOSR-83-0234 相似文献
205.
In this paper, new lower bounds for the asymmetric travelling salesman problem are presented, based on spanning arborescences. The new bounds are combined in an additive procedure whose theoretical performance is compared with that of the Balas and Christofides procedure (1981). Both procedures have been imbedded in a simple branch and bound algorithm and experimentally evaluated on hard test problems. 相似文献
206.
拉单晶问题数学模型弱解的存在性和唯一性 总被引:2,自引:0,他引:2
朱宁 《高校应用数学学报(A辑)》1995,(3):235-244
本文考虑楔形区域G0T上的二相自由边界问题:其中a,b,b1,νp,h2为正常数。本文在适当的假设之下,证明了上述定解问题弱解的存在性和唯一性。 相似文献
207.
The concept of multitasking mathematical programs is discussed, and an application of multitasking to the multiple-cost-row linear programming problem is considered. Based on this, an algorithm for solving the Linear Complementarity Problem (LCP) in parallel is presented. A variety of computational results are presented using this multitasking approach on the CRAY X-MP/48. These results were obtained for randomly generated LCP's where thenxn dense matrixM has no special properties (hence, the problem is NP-hard). based on these results, an average time performance ofO(n
4) is observed. 相似文献
208.
Michael J. Todd 《Mathematical Programming》1982,24(1):216-224
We show that piecewise-linear homotopy algorithms may take a number of steps that grows exponentially with the dimension when solving a system of linear equations whose solution lies close to the starting point. Our examples are based on an example of Murty exhibiting exponential growth for Lemke's algorithm for the linear complementarity problem.This research was supported in part by NSF grant ECS-7921279 and by a Guggenheim Fellowship. 相似文献
209.
Jeremy F. Shapiro 《Mathematical Programming》1984,29(1):113-119
Node aggregation methods have been previously studied as a means for approximating large scale transportation problems. In
this paper, we show how the approximations inherent in Benders' decomposition method can be combined with node aggregation
in optimizing large scale capacitated plant location problems.
This research was supported by the National Science Foundation under Grant No. ECS-8117105. 相似文献
210.
周仕荣 《漳州师范学院学报》2006,19(3):127-131
美国佛蒙特州数学问题解决和交流评价标准和量表重视学生学习的参与和体验过程,并能很好地结合现实生活和已有经验,全面考察学生的数学能力.这值得我们在数学教学过程中思考和借鉴. 相似文献