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1.
在允许缺货情况下的易变质产品供应商管理库存   总被引:7,自引:1,他引:6  
本首先通过解析推导给出了一个考虑一个供应商和多个不同的订货商,并且允许订货商缺货的易腐商品供应商管理库存VMI(Vendor Managed Inventory)模型;其次通过mathematica4.2软件计算。给出了算例及其最优解,并通过灵敏度分析讨论了单位缺货成本和变质率对库存决策的影响;最后给出了总结,说明了研究的意义。  相似文献
2.
基于非结构化模糊决策方法的设备采购方案评价   总被引:3,自引:0,他引:3  
为解决设备采购方案评价中存在的多目标决策问题以及弥补运用层次分析法(AHP法)和多因素价值理论(效用理论)解决此类问题的某些局限性,提出了运用非结构化模糊决策方法(NSFDM)进行设备采购方案评价。在论述了NSFDM的原理和步骤之后,以某项目空调系统采购为例,着重分析了NSFDM在设备采购方案评价中的应用。结果表明:相对于AHP法,NSFDM在建立层次结构模型时同一层次比较因素的数目可以超过9个,且判断矩阵易于通过一致性检验,因而NSFDM是解决设备采购方案评价和其它类似的复杂多目标决策问题的一种有效方法。  相似文献
3.
M-矩阵和H-矩阵在Fan积下的Oppenheim型不等式   总被引:2,自引:0,他引:2  
M-矩阵和H-矩阵在数学物理、经济学、数学规划等领域中有广泛的应用.对于一般的M-矩阵,是否成立著名的O ppenheim型不等式,文[1]给出了答案.本文建立了一个M-矩阵和一个H-矩阵在Fan积下的O ppenheim型不等式.  相似文献
4.
Yu Huang   《Chaos, Solitons & Fractals》2004,19(5):1105-1112
In 1978, Marotto generalized Li–Yorke’s results on the criterion for chaos from one-dimensional discrete dynamical systems to n-dimensional discrete dynamical systems, showing that the existence of a non-degenerate snap-back repeller implies chaos in the sense of Li–Yorke. This theorem is very useful in predicting and analyzing discrete chaos in multi-dimensional dynamical systems. Yet, besides it is well known that there exists an error in the conditions of the original Marotto Theorem, and several authors had tried to correct it in different way, Chen, Hsu and Zhou pointed out that the verification of “non-degeneracy” of a snap-back repeller is the most difficult in general and expected, “almost beyond reasonable doubt,” that the existence of only degenerate snap-back repeller still implies chaotic, which was posed as a conjecture by them. In this paper, we shall give necessary and sufficient conditions of chaos in the sense of Li–Yorke for planar monotone or competitive discrete dynamical systems and solve Chen–Hsu–Zhou Conjecture for such kinds of systems.  相似文献
5.
We are concerned with a moment problem for a nonlinear pseudoparabolic equation with one space dimension on an interval. The boundary conditions are imposed in terms of the zero-order moment and the first-order moment. Based on an elliptic estimate and an iteration method we established the well-posedness of solutions in the usual Sobolev space. We are able to get regularity of the solution so that both solution and its derivative with respect to the time variable belong to the same Sobolev space with respect to the space variable. This feature is different from problems with parabolic equations, where the regularity order of solution is higher than that of the time derivative with respect to the space variable. Previous results reflected only this parabolic nature for the pseudoparabolic equation.  相似文献
6.
黄煜  罗俊  周作领 《数学学报》2006,49(2):311-316
本文考虑闭区间上变差有界的连续映射f:I→I的局部变差增长γ(x,f)与局部拓扑熵h(x,f).将证明γ(x,f)≥h(x,f)对所有x∈I成立,并且局部变差增长映射γf(x)=γ(x,f)与局部拓扑熵映射sf(x)=h(x,f)都是上半连续的,得到一个变分原理:局部变差增长γ(x,f)与局部拓扑熵h(x,f)的上确界分别等于全局变差增长γ(f)=limn→∞1/nln Var(fn)与拓扑熵h(f).当映射f:I→I拓扑传递时,与Brin 和Katok对局部(测度)熵的讨论类似,我们证明,至多除一个不动点外,局部变差增长γ(x,f)与局部拓扑熵h(x,f)在开区间I°内恒为常值.  相似文献
7.
本文给出了四元数矩阵惯性的定义,讨论了四元数体上Lyapunov矩阵方程的唯一解,推广了一般惯性定理、Lyapunov稳定性定理、Carlson-Schneider定理、Stein稳定性定理等一些重要的结果到四元数矩阵,同时得出了四元数体上稳定矩阵的一些判别条件.  相似文献
8.
The central problem in dynamical systems is the asymptotic behavior or topological structure of the orbits. Nevertheless only orbits of points with certain recurrence and form a set of full measure are truly of importance. Of course, such a set is desired to be as small (in the sense of set inclusion) as possible. In this paper we discuss such two sets: the set of weakly almost periodic points and the set of quasi-weakly almost periodic points. While the two sets are different from each other by definitions, we prove that their closures both coincide with the measure center (or the minimal center of attraction) of the dynamical systems. Generally, a point may have three levels of orbit-structure: the support of an invariant measure generated by the point, its minimal center of attraction and its ω-limit set. We study the three levels of orbit-structure for weakly almost periodic points and quasi-weakly almost periodic points. We prove that quasi-weakly almost periodic points possess especially rich topological orbit-structures. We also present a necessary and sufficient condition for a point to belong to its own minimal center of attraction.  相似文献
9.
The proposed approach incorporated dynamic guiding approach and chaotic search procedure into particle swarm optimization (PSO), named DCPSO. Chaotic search, enjoyed ergodicity, irregularity and pseudo-randomness in PSO, would refine global best position evidently. And, dynamic guiding approach with fluctuating property would easily conduct unpredictable migrations for PSO to break away from evolutionary stagnation. The experiment reports indicated that the proposed DCPSO approach could improve the evolution performance significantly, and present the superiority in solving complex multidimensional problems.  相似文献
10.
赵宇  黄金莹  王希圆 《大学数学》2013,29(2):102-106
围绕多元函数条件极值问题展开讨论,指出利用函数凸性来解决优化分析问题的思想方法,并研究了两个与凸性相关的不等式.  相似文献
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