冷链物流同时送取货车辆路径优化

针对冷链物流同时送取货车辆路径优化问题,分析冷链物流配送中的车辆固定成本、行驶成本、制冷成本和货损成本等成本构成,以总成本最小化为目标,将冷链物流配送的送货和取货业务综合到每一个客户节点,建立单个配送中心和多个客户节点的冷链物流配送车辆路径优化模型,并采用遗传算法进行求解,算例分析验证了所建模型和设计算法的适用性和可行性,结果表明优化后的同时送取货车辆配送方案能够降低配送成本,提高配送效率,研究结论对冷链物流配送决策具有重要的参考价值.     

多品种生鲜农产品的车辆路径优化

针对多品种生鲜农产品建立了带软时间窗约束的车辆路径优化模型,模型以配送总成本最少为目标,以生鲜农产品新鲜度阈、时间窗等为约束条件.然后,通过引入Dijkstra算法,改进交叉算子,提出了针对上述模型的改进遗传算法.最后,以上海市交通道路生鲜农产品配送作为案例,对算法进行测试.     

带时间窗的三维装载物流配送优化方法研究

针对城市物流配送优化研究在客户服务时间窗和货物装载方式合理结合方面存在的不足,考虑物流配送车厢货物装载方式与客户访问序列相关的特征对车厢空间进行合理的区域划分。首先,构建了包含配送中心的固定成本、配送车辆的运输成本、维修成本、租赁成本和违反时间窗惩罚成本的物流运营成本最小化和配送车辆空间利用率最大化的双目标优化模型;然后,提出一种结合遗传算法(GA)全局搜索能力和禁忌搜索算法(TS)局部搜索能力的GA-TS混合算法求解模型;最后,结合重庆市某配送中心的三维装载物流配送实例数据进行了优化计算,实验结果给出了带时间窗的三维装载物流配送路径优化方案,并进行了不同车厢空间分区模式下平均装载率、物流运营成本和车辆使用数的比较分析。研究表明,当客户需求货物种类数与车辆的空间区域划分数相等且按货物类型进行区域划分时,物流运营成本最小,配送车辆使用数最少和车辆平均装载率最高。     

基于GIS和禁忌搜索集成技术的农产品物流配送路径优化

分析农产品物流配送模式,对带时间窗的车辆路径问题进行描述,建立有时限的配送路径优化模型,应用GIS与禁忌搜索算法集成技术求解该模型,开发农产品物流配送路径优化系统,并以晋安区农产品物流配送基础数据为范例,进行系统的初步应用研究.     

客户动态变更配送需求的配送路线优化研究

针对物流配送途中客户动态变更配送需求问题,分别研究了满足客户临时变更收货时间窗、收货地址和取消收货的三种要求时所需成本相较于预先设计配送路径所需成本的波动值,建立了客户临时变更配送需求的动态管理模型.基于嵌套分割算法,设计了邻近救援策略、最佳离库策略、增派车辆策略对模型进行求解.最后,通过算例试验,证明模型可以有效的降低物流配送成本,且具有更强的实用性、灵活性,且嵌套分割算法还在数据优化、计算时间上有显著成效.     

基于遗传算法的成品油二次配送车辆路径问题研究

研究了加油站需求已知前提下带时间窗的具有满隔舱运输约束的多车型成品油二次配送车辆路径问题.首先以总费用极小化为目标建立了具有满载运输约束的多车型成品油二次配送车辆路径问题的混合整数规划模型,其中总费用包括动用车辆的固定费用、车辆的运输费用、以及不满足时间窗约束的等待成本和惩罚成本等.然后基于成品油二次配送车辆路径问题的特点设计了求解模型的遗传算法,通过对车辆和加油站分别采用自然数编码方式、解码时考虑约束条件等策略有效避免了不可行解的产生.最后利用一个实际案例进行了模拟计算,结果显示根据方法得到的配送方案明显优于实际中凭经验得到的配送方案,总配送成本大约降低了9%.模型和算法为制订成品油二次配送方案提供了决策依据.     

多时间窗车辆路径问题的智能水滴算法

研究了多时间窗车辆路径问题,考虑了车容量、多个硬时间窗限制等约束条件,以动用车辆的固定成本和车辆运行成本之和最小为目标,建立了整数线性规划模型。根据智能水滴算法的基本原理,设计了求解多时间窗车辆路径问题的快速算法,利用具体实例进行了模拟计算,并与遗传算法的计算结果进行了对比分析,结果显示,利用智能水滴算法求解多时间窗车辆路径问题,能够以很高的概率得到全局最优解,是求解多时间窗车辆路径问题的有效算法。     

基于即时配送和收益激励的众包物流运力调度研究

基于参与众包物流配送模式的人员闲散、积极性不高,以及客户对即时配送要求并非完全刚性的特征,引入模糊时间窗,将客户满意度量化为众包物流配送人员到达客户位置时刻的模糊隶属度函数。在一定客户满意度下,以最大化众包物流配送人员收益为目标,构建了基于即时配送和收益激励的众包物流运力调度问题模型,考虑到机会、逾时、超载惩罚成本,利用带有动态权重的粒子群算法,通过算例验证分析,结果表明该模型在保证客户满意度和提高众包物流配送人员积极性方面具有可行性和有效性。     

错误规避视角下生鲜农产品物流配送方案的决策分析

在生鲜农产品物流配送过程中,时间不当、成本过高、损耗过多、碳排放过高等现象都属于错误.减少物流配送过程中的错误对提高生鲜农产品的物流配送效率具有重要意义.从错误规避这一视角出发,在给出相关概念与假设的基础上,按照建立判断规则、构建错误函数、方案排序与选优的步骤构建一种关于生鲜农产品物流配送方案的选择方法.方法用"错误"对生鲜农产品物流配送过程中可能存在时间不当、成本过高、损耗过多、碳排放过高的问题进行统一描述,实现对不同方面决策信息的融合,能够有效筛选和剔除不可行方案,兼顾整体发展和协调发展.方法的应用有利于进一步提高生鲜农产品物流配送方案选择的科学性.     

基于客户信用度的物流配送车辆路径问题研究

针对当前城市物流配送过程中普遍存在的客户中途取消订单、无故退换货等交易违约问题,引入客户信用度的测度方法。根据客户历史交易违约数据计算客户信用值,并转化求解客户信用度,构建了包含车辆配送成本、租赁成本以及违反时间窗惩罚成本的配送路径优化模型。设计了一种遗传(GA)-禁忌搜索(TS)混合算法进行模型求解,在算法过程中应用精英保留策略进行循环迭代寻优。结合重庆某外卖物流配送网络的实例数据,验证了模型和算法的有效性和可行性。实验结果给出了不同服务策略下的物流配送调度方案,并进行了基于客户信用度的客户配送服务序列调整比较和敏感度分析。研究表明客户信用等级的合理划分可以有效降低物流配送成本和提高客户服务水平。     

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.     

On a class of self-similar processes with stationary increments in higher order Wiener chaoses

We study a class of self-similar processes with stationary increments belonging to higher order Wiener chaoses which are similar to Hermite processes. We obtain an almost sure wavelet-like expansion of these processes. This allows us to compute the pointwise and local Hölder regularity of sample paths and to analyse their behaviour at infinity. We also provide some results on the Hausdorff dimension of the range and graphs of multidimensional anisotropic self-similar processes with stationary increments defined by multiple Wiener–Itô integrals.     

A REPRESENTATION FORMULA RELATED TO SCHR(O)DINGER OPERATORS

Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.     

On a class of Riemann surfaces

It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary.     

CONTENTS OF VOLUME 30

正~~     

Instructions for contributions

正Applied Mathematics-A Journal of Chinese Universities,Series B(Appl.Math.J.Chinese Univ.,Ser.B)is a comprehensive applied mathematics journal jointly sponsored by Zhejiang University,China Society for Industrial and Applied Mathematics,and Springer-Verlag.It is a quarterly journal with     

Journal of Mathematical Research with Applications Guide for Authors

正Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.     

Staircase transportation problems with superadditive rewards and cumulative capacities

A cumulative-capacitated transportation problem is studied. The supply nodes and demand nodes are each chains. Shipments from a supply node to a demand node are possible only if the pair lies in a sublattice, or equivalently, in a staircase disjoint union of rectangles, of the product of the two chains. There are (lattice) superadditive upper bounds on the cumulative flows in all leading subrectangles of each rectangle. It is shown that there is a greatest cumulative flow formed by the natural generalization of the South-West Corner Rule that respects cumulative-flow capacities; it has maximum reward when the rewards are (lattice) superadditive; it is integer if the supplies, demands and capacities are integer; and it can be calculated myopically in linear time. The result is specialized to earlier work of Hoeffding (1940), Fréchet (1951), Lorentz (1953), Hoffman (1963) and Barnes and Hoffman (1985). Applications are given to extreme constrained bivariate distributions, optimal distribution with limited one-way product substitution and, generalizing results of Derman and Klein (1958), optimal sales with age-dependent rewards and capacities.To our friend, Philip Wolfe, with admiration and affection, on the occasion of his 65th birthday.Research was supported respectively by the IBM T.J. Watson and IBM Almaden Research Centers and is a minor revision of the IBM Research Report [6].     

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.