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951.
952.
定义了拓扑指数Si(i=1,2,3,4),并选取包含双、三键、环及苯环的碳氢化合物为研究对象,计算了这些化合物的拓扑指数Si,同时用Si相关了它们的沸点.结果较文献值有所改善.并从Si中筛选出了S 相似文献
953.
若干有关欧阳不等式的非线性积分不等式和离散不等式 总被引:10,自引:0,他引:10
获得几个非线性的积分不等式及离散不等式.它们和近期Pachpate[1]中欧阳亮不等式[2]的推广有关.作为特殊情形还导出了一些具有幂非线性的新不等式.为说明结果的有用性,讨论了某个非线性差分方程解的有界性. 相似文献
954.
YANG BENFU 《高校应用数学学报(英文版)》1994,9(3):291-297
USINGFINITEGEOMETRIESTOCONSTRUCT3-PBIB(2)DESIGNSAND3-DESIGNS¥YANGBENFU(DepartmentofMathematics,ChengduTeachersCollege,Chengdu... 相似文献
955.
杨力平 《应用数学学报(英文版)》1994,10(3):233-251
FREEBOUNDARYPROBLEMARISINGFROMEVAPORATIONFROMPOROUSMEDIUMYANGLIPING(杨力平)(DepartmentofAppliedMathematics,TsinghuaUniversity,Be... 相似文献
956.
This paper reports the results of a survey intended to discover the extent to which Checkland's Soft Systems Methodology (SSM) is used in practice. Some 300 questionnaires were sent to people who had had some exposure to SSM and, surprisingly, nearly half were returned. The majority described in detail their uses of SSM and most felt that it had been successful. This paper describes the overall quantitative results from the survey as well as presenting a qualitative analysis of the experiences of using SSM. 相似文献
957.
Eugenio Hernández Xihua Wang Guido Weiss 《Journal of Fourier Analysis and Applications》1997,3(1):23-41
The main purpose of this paper is to give a procedure to “mollify” the low-pass filters of a large number ofMinimally Supported Frequency (MSF) wavelets so that the smoother functions obtained in this way are also low-pass filters for an MRA. Hence, we are able
to approximate (in the L
2
-norm) MSF wavelets by wavelets with any desired degree of smoothness on the Fourier transform side. Although the MSF wavelets
we consider are bandlimited, this may not be true for their smooth approximations. This phenomena is related to the invariant
cycles under the transformation x ↦2x (mod2π). We also give a characterization of all low-pass filters for MSF wavelets. Throughout the paper new and interesting examples
of wavelets are described. 相似文献
958.
Preparation of Papers 总被引:8,自引:0,他引:8
We motivate the study of a vector variational inequality by a practical flow equilibrium problem on a network, namely a generalization of the well-known Wardrop equilibrium principle. Both weak and strong forms of the vector variational inequality are discussed and their relationships to a vector optimization problem are established under various convexity assumptions. 相似文献
959.
Traditional inventory models assume that a buyer places one order with a supplier in each order cycle. A large number of researchers have studied the benefits of dual sourcing such that an order quantity is split and placed simultaneously with two suppliers. We show that many of the benefits of dual sourcing are due to order splitting rather than using two suppliers. We investigate order splitting with one supplier such that the first part of the order is sent out immediately but the second part of the order is released later (scheduled-release). Through extensive computational results, we show that in many situations where dual sourcing or the use of a cheaper supplier would be cost effective, single sourcing with order splitting using scheduled-release orders is better. The paper provides a quantitative rationale to continue with one supplier. We also summarize the qualitative reasons to prefer single sourcing or multiple sourcing. 相似文献
960.