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111.
Joint logistics and financial services by a 3PL firm 总被引:4,自引:0,他引:4
Xiangfeng Chen 《European Journal of Operational Research》2011,214(3):579-587
Integrated logistics and financial services have been practiced by third party logistics (3PL) firms for years; however, the literature has been silent on the value of 3PL firms as credit providers in budget-constrained supply chains. This paper investigates an extended supply chain model with a supplier, a budget-constrained retailer, a bank, and a 3PL firm, in which the retailer has insufficient initial budget and may borrow or obtain trade credit from either a bank (traditional role) or a 3PL firm (control role). Our analysis indicates that the control role model yields higher profits not only for the 3PL firm but also for the supplier, the retailer, and the entire supply chain. In comparison with a supplier credit model where the supplier provides the trade credit, the control role model yields a better performance for the supply chain as long as the 3PL firm’s marginal profit is greater than that of the supplier. We further demonstrate that, for all players, both the control role and supplier credit models can outperform the classic newsvendor model without budget constraint. 相似文献
112.
The combined finite volume–finite element scheme for a double nonlinear parabolic convection-dominated diffusion equation which models the variably saturated flow and contaminant transport problems in porous media is extended. Whereas the convection is approximated by a finite volume method (Multi-Point Flux Approximation), the diffusion is approximated by a finite element method. The scheme is fully implicit and involves a relaxation-regularized algorithm. Due to monotonicity and conservation properties of the approximated scheme and in view of the compactness theorem we show the convergence of the numerical scheme to the weak solution. Our scheme is applied for computing two dimensional examples with different degrees of complexity. The numerical results demonstrate that the proposed scheme gives good performance in convergence and accuracy. 相似文献
113.
广义严格对角占优矩阵在计算数学、数学物理、控制论等众多领域有着广泛而重要的应用.但实际判断一个矩阵是否为广义严格对角占优矩阵却是困难的.本文利用α-对角占优矩阵的性质,给出了广义严格对角占优矩阵的几个判定条件,扩大了判别范围. 相似文献
114.
Let q1 and q2 belong to a certain class of normalized analytic univalent functions in the open unit disk of the complex plane. Sufficient conditions are obtained for normalized analytic functions p to satisfy the double subordination chain q1(z)?p(z)?q2(z). The differential sandwich-type result obtained is applied to normalized univalent functions and to Φ-like functions. 相似文献
115.
以M-矩阵以及α-对角占优矩阵为工具,对0≤α≤1,借助Hlder不等式给出了广义严格对角占优矩阵以及非奇异M-矩阵的几则新的充分条件,拓广了近期的一些相关结果,并用数值例子说明这些结果的有效性. 相似文献
116.
In this paper, we first discuss a class of inverse dominant problems under weighted l∞ norm, which is how to change the original weights of elements with bounds in a finite ground set so that a given set becomes
a weakly dominant set with respect to a given collection of subsets under the new weights and the largest change of the weights
is minimum. This model includes a large class of improvement problems in combinatorial optimization. We propose a Newton-type
algorithm for the model. This algorithm can solve the model in strongly polynomial time if the subproblem involved is solvable
in strongly polynomial time. In the second part of the paper, we improve the complexity bound for Radzik’s Newton-type method
which is designed to solve linear fractional combinatorial optimization problems. As Radzik’s method is closely related to
our algorithm, this bound also estimates the complexity of our algorithm.
Supported by the Hong Kong Universities Grant Council (CERG CITYU 9040883 and 9041091).
Xiaoguang Yang - The author is also grateful for the support by the National Key Research and Development Program of China
(Grant No. 2002CB312004) and the National Natural Science Foundation of China (Grant No. 70425004). 相似文献
117.
1引言 设A=(a_η)∈Cm~(3n),若存在正对角阵D.使得AD为严格对角占优矩阵,则A称为广义严格对角占优矩阵,记作A∈SGDDM. 相似文献
118.
矩阵特征值新的包含域 总被引:2,自引:0,他引:2
本文给出了矩阵特征值一个新的包含域,在此基础上得到了对角占优矩阵非奇异的一个新的简单的判别法,所得结论推广了[1]中一个主要结论. 相似文献
119.
关于广义对角占优矩阵判别的注记 总被引:7,自引:0,他引:7
黎稳 《高等学校计算数学学报》1997,19(1):93-96
1 引言 最近,文[4]给出了H-矩阵的若干简捷判据。在此,我们把它的其中两个主要结果作一公共推广,使判别范围放宽。此外,我们还给出不可约矩阵是广义对角占优的一个判别条件。 若没有特别说明,本文所使用的符号与术语皆与[6]同。此外,我们还使用如下符号。 设n为正整数,记 相似文献
120.
研究了在板模型中一类带广义边界条件具各向异性、单能、均匀介质迁移算子A的谱,证明了其生成的c0半群Dyson—Phillips展开式的二阶余项是紧的,从而得到迁移算子A的一些谱性质。 相似文献