冷链低碳物流配送路径优化的细菌觅食—蚁群算法研究

冷链物流的绿色发展已成为国家十三五发展的热点,在分析冷链物流配送环节各种成本基础上,以车载容量和时间窗为约束,构建综合总成本最小化的冷链低碳物流配送路径优化模型.将细菌觅食算法中的复制操作和趋向操作引入基本蚁群算法中,改善了算法的收敛效率和全局搜索能力,提出了细菌觅食一蚁群算法用于求解冷链低碳物流配送路径优化模型.通过实例仿真表明,在求解冷链低碳物流配送路径优化模型方面,细菌觅食—蚁群算法能够以更高的效率寻找到更低的综合总成本,验证了改进算法的合理性和有效性.     

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.     

综合考虑碳排放与运输费用的配送路径优化

针对日益严峻的环境问题,在传统的物流配送路径优化过程中,进行碳排放量计算,并转换成相应的经济效益,形成一个综合考虑碳排放和运输费用的配送路径优化模型并通过遗传算法进行求解.以厦门市某物流配送企业为例进行初步应用研究.结果表明:传统的配送路径安排中存在很大的碳排放改善空间;综合考虑碳排放和运输费用的车辆路径问题在有效实现绿色物流的同时能降低运输成本.     

第3方冷链物流配送路径优化研究

根据冷链物流配送具有的特殊性,进一步探索冷链物流配送优化研究的方案.在保证货物不超载的情况下,建立以一个冷链配送中心、多个顾客的冷链物流的配送数学模型,用改进遗传算法加以分析求解,并采用Matlab软件对算法进行编程,最后通过算例进行验证.得到如下结论:利用改进遗传算法得到的最优配送路线优于标准遗传算法求解结果.     

基于精英单亲遗传算法的冷链物流VRP模型优化研究

针对冷链物流配送的特殊性,探索冷链物流车辆路径问题(VRP)优化方案.首先,在保证货物不超载的条件下,建立基于时间和品质因素的顾客满意度约束的多配送中心VRP(MDVRP)模型;其次,采用重心分区法和改进的精英单亲遗传算法,求解顾客在配送中心的分配,确定配送车辆数以及顾客服务次序;最后,用Matlab工具编程对模型进行求解分析.结果表明构建基于满意度的冷链物流MDVRP模型更适合冷链物流配送最优路径选择,并且改进单亲遗传算法能够有效求解这类问题.     

物流配送车辆路径问题的鲁棒优化方法

针对物流配送中的不确定性因素,构建车辆路径间题的鲁棒性度量与优化方法,目的是降低不确定性因素对物流配送系统的影响.首先,提出车辆路径问题的鲁棒性度量指标,利用算例对各指标的效果进行分析,选择适用于度量车辆路径方案鲁棒性的指标.在此基础上,设计物流配送车辆路径规划的两阶段优化算法.算法的第一阶段不考虑车辆路径的鲁棒性,以总配送成本最小为目标函数优化配送方案;算法的第二阶段以鲁棒性度量指标最大为目标函数,以第一阶段获得的总成本与车辆数为约束条件,优化鲁棒调度方案.文章为车辆路径问题的鲁棒性度量提供了一种有效方法,同时为如何平衡供应链中的物流配送环节的服务作业成本与调度方案鲁棒性提供了思路.     

碳排放限制下的冷藏集装箱多式联运路径优化

为了降低碳排放限制下的冷藏集装箱多式联运成本,实现节能减排的目的,高效的路径选择至关重要.该文基于碳排放限制的视角,针对多式联运网络中铁路和水路运输具有发班时间限制,以及冷藏集装箱需要考虑制冷费用、货损货差的特点,建立了在碳排放限制下以总成本最低为目标的优化模型.构建总成本时不仅考虑了运输费用和转运费用,还考虑了受发班时间影响而动态变化的冷藏费用和货损费用.设计了遗传算法求解,并进行了算例分析.结果表明:通过该模型和算法,可根据决策者的要求快速地选出成本最少的运输方案,为决策者提供决策支持.     

蝙蝠算法在物流配送车辆路径优化问题中的应用

车辆路径问题(Vehicle Routing Problem,VRP)是组合优化问题中一个典型的NP难题.蝙蝠算法(Bat Algorithm,BA)是一种新型的智能优化算法,尚未被应用到求解VRP问题中去.根据物流配送中VRP问题的数学模型及其具体特征,设计了求解VRP问题的蝙蝠算法,并通过仿真实例和与其他算法进行比较的方式验证了蝙蝠算法求解VRP问题的有效性与可行性.     

基于改进鲸鱼优化算法的物流路径优化

针对物流配送车辆路径难以优化以至于影响物流配送系统效率和效益的问题,提出一种基于鲸鱼优化算法的车辆路径优化方法.首先,建立物流配送系统数学模型.其次,针对传统鲸鱼优化算法易陷入局部最优的问题,采用随机惯性权重和非均匀变异策略对算法进行改进,并用过测试函数对比试验验证了所提方法的有效性.最后通过改进的鲸鱼优化算法进行物流路径优化实验,实验结果验证了所提出的改进鲸鱼优化算法能够高效的优化物流配送车辆路配送路径,降低了物流配送成本.     

改进蚁群算法在应急VRP问题中的应用研究

提出一种改进的蚁群算法优化应急物流配送车辆路径问题算法,设计了应急物流配送车辆路径问题的数学模型,并利用计算机进行了仿真实验.实验结果表明,方法能有效解决应急物流配送车辆路径问题,具有一定的理论价值和实际意义.     

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.     

Qualitative Analysis of Bifurcating Solutions in the Lengyel-Epstein Model

One of the most fundamental problems in theoretical biology is to explain the mechanisms by which patterns and forms are created in the＇living world. In his seminal paper ＂The Chemical Basis of Morphogenesis＂, Turing showed that a system of coupled reaction-diffusion equations can be used to describe patterns and forms in biological systems. However, the first experimental evidence to the Turing patterns was observed by De Kepper and her associates（1990） on the CIMA reaction in an open unstirred reactor, almost 40 years after Turing＇s prediction. Lengyel and Epstein characterized this famous experiment using a system of reaction-diffusion equations. The Lengyel-Epstein model is in the form as follows     

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.     

(0,1 ;0)-INTERPOLATION ON INFINITE INTERVAL (-∞, +∞)

In this paper, we study the explicit representation and convergence of (0, 1; 0)-interpolation on infinite interval, which means to determine a polynomial of degree ≤ 3n - 2 when the function values are prescribed at two set of points namely the zeros of Hn(x) and H′n(x) and the first derivatives at the zeros of H′n(x).     

CONTENTS OF VOLUME 30

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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].