考虑顾客退货和固定成本的联合补货与定价策略

为了吸引更多顾客,许多电子商务零售商允许顾客在一定时间内退货,导致其利润明显减少。同时,在补货时不仅产生依赖补货量的变动成本,而且会产生与补货量无关的固定成本。基于此,以最大化电子商务零售商的利润为目标,建立考虑顾客退货和固定成本的联合补货与定价模型,其中顾客的退货量与满足的需求呈正比。在一般需求情形下,部分刻画多期问题的最优策略;在特殊需求情形下,证明(s,S,p)策略对单期问题最优,并对多期问题的最优策略进行严格刻画。根据已有刻画为多期问题构造启发式策略。数值结果表明启发式策略近似最优;当初始库存水平足够高/低时,最优补货水平和定价随退货率与固定成本单调变化。关键词:联合补货与定价模型;顾客退货;固定成本;随机动态规划;最优策略     

带短期价格折扣和允许两次特殊补货的库存决策模型

针对供应商提供短期价格折扣且允许零售商两次特殊补货的库存系统, 建立了以零售商库存效益最大化为目标的库存决策模型, 分析了模型的性质, 根据经济订单批量补货决策下补货时间点与折扣时段的关系, 确定了零售商在不同补货策略下的库存效益增值函数. 据此给出零售商相应的最优补货策略函数表达式, 提出了该模型的一个全局优化算法, 并通过数值算例验证了模型和算法的有效性与可行性.     

基于贝叶斯信息更新的动态库存与定价研究

考虑价格对需求量的扰动并利用贝叶斯公式对需求分布函数中的未知参数进行不断学习更新,研究缺货部分比例延迟交货情形下的动态库存与动态定价问题,刻画了最优利润函数的性质并证明了"基准库存列表价格"是最优的库存价格水平,并由此得到了最优的补货策略和定价策略。     

基于(Q,R)补货的双渠道供应链库存模型研究

制造商在引入网络直销渠道后,需有效协调与零售商之间的物流冲突.以销售单一产品,只有一个制造商和零售商,且制造商的补货策略为(Q,R)策略,零售商的补货策略为一对一策略的双渠道供应链系统作为研究对象,在综合考虑消费者渠道偏好和由于销售渠道缺货所引起的消费者转移的前提下,结合Markov过程理论建立供应链系统库存模型,针对制造商和零售商的库存决策进行分析.分析表明,制造商存在R~*及Q~*,零售商存在库存水平S~*使供应链系统的收益最大.MATLAB仿真表明了该结论的有效性.     

基于(Q,r)补货策略的寄售库存模式研究

本文运用数学建模和数值分析的方法研究了基于(Q,r)补货策略的寄售库存模式中合同参数的优化问题。在该模式下,供应商确定Q、r值,并维持(z,Z)的库存水平,零售商对低于下限z或超过上限Z的库存收取罚金b。研究结果表明,零售商可以通过设置合理的罚金b来激励供应商选择合理的r和Q,使得最低的期望库存水平高于z,并且使成本达到最优。     

具有Weibull生存死亡特征的冷链品库存补货定价策略研究

建立了无限期内冷链品具有Weibull生存死亡特征、随机需求且受售价影响的库存补货定价模型,其中售价是连续变化的,需求率是售价的指数函数,变质率服从的三参数Weibull分布,提前期固定。系统以利润最大化为目标函数,在(r,Q)库存策略下,建立库存模型,采用直接法,对模型近似求解,得到最优补货定价策略。利用Matlab进行算例模拟和灵敏度分析发现:补货提前期和单位仓储成本对补货定价策略影响较大,二者增大会导致系统利润降低;单位处理成本的增加,在一定程度上使得系统降低最优补货量,使系统利润增加;保鲜期固定的前提下,受冷链品的流动环境因子和存储环境因子影响的变质率对补货定价策略影响较大,它的增大会使系统利润降低。这些发现能够帮助优化系统模型,对现实问题具有一定的指导意义。     

基于收益共享契约的零售商押金补货策略研究

押金补货是指零售商在第一阶段向供应商交纳一定的押金,在接下来的阶段中不需要再交纳额外的补货费用的补货方式。对于中小型零售商,它的补货策略往往受到自有资金的约束,当自有资金不足以订到报童模型的最优补货量时,不仅自身收益受到影响,还会影响到整条供应链的收益,本文研究了在随机市场需求,且零售商能够随时向银行贷款的情况下,基于收益共享契约的零售商的押金融资订货策略。本文从两阶段出发,分析零售商的最优订货策略,研究表明,零售商的补货策略受初始资产和收益共享系数的影响。最后,文章将其扩展到多阶段问题进行讨论。     

回收努力分配策略对闭环供应链定价决策的影响

以零售商、制造商和回收商组成的闭环供应链为研究对象,基于回收努力对回收量和回收质量的影响,建立零售商主导下的闭环供应链定价模型.其中回收努力分为横向努力和纵向努力,前者提高回收量,后者提高回收质量.基于Stackelberg博弈理论求解模型,分析再造品认知度、回收努力及其分配策略对供应链的影响,探讨最优的回收努力分配策略.研究发现:再造品认知度越高,供应链利润越高;在一定范围内提升回收努力水平,有利于提升供应链成员利润,但是超过特定阈值会使得回收商和供应链整体利润下降;最优回收努力分配策略依赖于横向与纵向努力的成本系数,直接将回收努力全部用于提升回收量或者回收质量可能会损害供应链利润.     

随机需求下具有有效期的易变质物品的库存管理北大核心CSCD

本本文研究了无限时间具有有效期的易变质物品的(T,r,Q)的库存补货策略.在市场需求率随机,允许缺货且设定最大缺货量的条件下,建立了一个确定易变质物品最优补货策略的优化模型,并采用缺货回补的办法,利用多元极值和隐函数定理的思想得到了最优补货批量和订货点.在最后的算例中,通过Matlab软件模拟出最优补货批量和最优缺货量,并对模型的参数作了灵敏性分析.     

随机需求下具有有效期的易变质物品的库存管理

本本文研究了无限时间具有有效期的易变质物品的(T,r,Q)的库存补货策略.在市场需求率随机,允许缺货且设定最大缺货量的条件下,建立了一个确定易变质物品最优补货策略的优化模型,并采用缺货回补的办法,利用多元极值和隐函数定理的思想得到了最优补货批量和订货点.在最后的算例中,通过Matlab软件模拟出最优补货批量和最优缺货量,并对模型的参数作了灵敏性分析.     

RECENT PROGRESS ON SPHERICAL HARMONIC APPROXIMATION MADE BY BNU RESEARCH GROUP ——In memory of Professor Sun Yongsheng

As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years （2001-2005）. The main topics are： convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.     

A unified approach to certain problems of best local approximation

In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.     

Boundedness for commutators of multipliers on Hardy type spaces

In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p（R^n） into the Lebesgue space L^p with p 〈 1.     

THE 8~(th) INTERNATIONAL CONGRESS ON INDUSTRIAL AND APPLIED MATHEMATICS

<正>August 10-14,2015Beijing,ChinaThe International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists     

Towards Excellence in Science Chinese Academy of Sciences

<正>May 26,2014,Beijing Science is a human enterprise in the pursuit of knowledge.The scientific revolution that occurred in the 17th Century initiated the advances of modern science.The scientific knowledge system created by     

Bounds for the zeros of polynomials

Let P(z)=∑↓j=0↑n ajx^j be a polynomial of degree n. In this paper we prove a more general result which interalia improves upon the bounds of a class of polynomials. We also prove a result which includes some extensions and generalizations of Enestrǒm-Kakeya theorem.     

Boundedness of commutators related to Marcinkiewicz integrals on hardy type spaces

In this paper, the authors study the boundedness of the operator [μΩ, b], the commutator generated by a function b ∈ Lipβ(Rn)(0 ＜β≤ 1) and the Marcinkiewicz integrals μΩ, on the classical Hardy spaces and the Herz-type Hardy spaces in the case Ω∈ Lipα(Sn-1)(0 ＜α≤ 1).     

Jacobi polynomials used to invert the laplace transform

Given the Laplace transform F(s) of a function f(t), we develop a new algorithm to find an approximation to f(t) by the use of the classical Jacobi polynomials. The main contribution of our work is the development of a new and very effective method to determine the coefficients in the finite series expansion that approximation f(t) in terms of Jacobi polynomials. Some numerical examples are illustrated.     

Generalization of the interaction between Haar approximation and polynomial operators to higher order methods

In applications it is useful to compute the local average empirical statistics on u. A very simple relation exists when of a function f（u） of an input u from the local averages are given by a Haar approximation. The question is to know if it holds for higher order approximation methods. To do so, it is necessary to use approximate product operators defined over linear approximation spaces. These products are characterized by a Strang and Fix like condition. An explicit construction of these product operators is exhibited for piecewise polynomial functions, using Hermite interpolation. The averaging relation which holds for the Haar approximation is then recovered when the product is defined by a two point Hermite interpolation.