Optimal Positioning of a Mobile Service Unit on a Line

In this paper we address the problem of locating a mobile response unit when demand is distributed according to a random variable on a line. Properties are proven which reduce the problem to locating a non-mobile facility, transforming the original optimization problem into an one-dimensional convex program.In the special case of a discrete demand (a simple probability measure), an algorithm which runs in expected linear time is proposed.     

目的地充电站电动汽车充电设施优化配置

为了研究城市商业区目的地充电站的设施优化问题,本文在充分考虑快、慢充电设施充电时间的差异性和顾客在目的地接受充电时间异质性的基础上,构建了针对两类服务设施的排队论模型,同时以将同类型服务设施并联视为一台大型服务设施为出发点,这一出发点的可行性通过对M/M/1和M/M/n模型的相关指标值比对进行了验证;然后,在窗口能力不等的多服务窗排队系统中纳入已并联的快充与慢充充电设施,在获得模型基本参数基础上,再运算得到稳态方程及相关指标值,在此基础上构建了使用方与建设方综合服务费用最小的目标函数。本文末对所提出方法可行性与优越性由算例与对比分析进行了证实。     

不确定环境下服务资源配置优化

在服务资源配置过程中,按维修状态将服务对象分成三类:完全维修、部分维修及最小维修.由于维修服务的特性,服务成本与服务时间均是一个模糊数,并且维修对象在服务时所处的维修状态也具有一定的不确定性.针对这类情况下的服务资源配置问题,提出了同时考虑模糊服务成本和模糊服务时间及不确定维修状态的最小化服务成本为优化指标的服务资源配置模型.在模型的求解过程中采用多粒子群算法,通过仿真计算表明了该方法的可行性和有效性.     

Optimal Equipment Transfer Pricing in Service Systems

A model for determining optimal equipment transfers in a multi-location, multi-period server system is presented. For a reasonable number of locations, the size of the resulting program prevents straightforward global optimization. A decomposition procedure is developed which allows each location to be treated separately. Control of equipment transfers between locations is obtained by adjustment of a set of holding costs, one for each period. These holding costs are determined such that the supply of unwanted units, by some locations, is met by the demand for these units by other locations. Unused units remain idle for the period. The procedure introduced here is interesting in that it allows a firm to operate their service facilities in a profit-centered fashion. Computational results are reported in the paper and extensions of this approach to other, similar types of managerial problems are suggested.     

Robust Optimal Service Analysis of Single-Server Re-Entrant Queues

We generalize the analysis of J.A. Ball, M.V. Day, and P. Kachroo (Mathematics of Control, Signals, and Systems, vol. 12, pp. 307–345, 1999) to a fluid model of a single server re-entrant queue. The approach is to solve the Hamilton-Jacobi-Isaacs equation associated with optimal robust control of the system. The method of staged characteristics is generalized from Ball et al. (1999) to construct the solution explicitly. Formulas are developed allowing explicit calculations for the Skorokhod problem involved in the system equations. Such formulas are particularly important for numerical verification of conditions on the boundary of the nonnegative orthant. The optimal control (server) strategy is shown to be of linear-index type. Dai-type stability properties are discussed. A modification of the model in which new customers are allowed only at a specified entry queue is considered in 2 dimensions. The same optimal strategy is found in that case as well.     

Solving a Bicriteria Problem of Optimal Service Centers Location

The problem of service centers location is formulated as a bicriteria optimization problem of finding a dominating set in graph. We investigate the properties of this problem and propose the methods for its solving. The results of computational experiment for instances with random data are presented.     

专有服务机制下提供免费体验服务的服务系统优化设计研究

通过提供免费的体验服务,服务系统可以吸引潜在顾客成为忠实顾客。本文考虑专有服务机制下提供免费体验服务和付费(常规)服务的服务系统,基于顾客的延时敏感特性,利用排队论的矩阵分析方法和谱扩展方法,研究服务系统的相关性能指标以及服务系统的优化设计,进而构建服务提供商利润函数并通过数值实例来获得免费体验服务的最优服务速率以及常规服务收取的最优服务费用,并为服务提供商提供相应的管理启示。研究表明,当越来越多的体验顾客转为付费顾客时,服务提供商需要降低体验服务的服务速率,来缓解系统的拥堵情况,减少顾客的逗留时间,并且服务提供商需要降低常规服务的服务费来弥补顾客因拥堵而造成的服务延迟。新到达顾客选择体验服务的人数越多时,服务提供商需要大幅度降低常规服务的收费标准,来吸引体验顾客成为付费顾客。     

社会互动视角下的服务型企业最优运营策略研究

本文主要研究在社会互动的影响下,服务型企业如何制定以价格、服务速率为代表的运营管理策略,从而实现利润最大化。首先,基于M/M/1排队模型对顾客购买决策过程进行建模分析,考虑单个服务型企业在实现利润最大化的目标条件下,社会互动的作用如何影响定价和服务速率决策;其次,研究在竞争市场环境中,社会互动如何影响市场均衡状态下各企业的运营决策和市场份额。结果表明,无论在垄断还是竞争的市场环境中,社会互动对服务型企业的最优运营决策均有不同程度与方向的影响。     

变参数随机服务系统最优设计

利用排队理论，建立了一个到达率递增、服务率不变、服务台数量递减的变参数随机服务系统最优设计模型。给出了满足投资有限，在一定时期内设备使用率和用户服务质量满足给定的要求，使用寿命达到设计的服务系统最优设计方案。     

Optimal Open-Loop Control of Vacations,Polling and Service Assignment

We consider in this paper the optimal open-loop control of vacations in queueing systems. The controller has to take actions without state information. We first consider the case of a single queue, in which the question is when should vacations be taken so as to minimize, in some general sense, workloads and waiting times. We then consider the case of several queues, in which service of one queue constitutes a vacation for others. This is the optimal polling problem. We solve both problems using new techniques from [2,4] based on multimodularity.     

Optimal Operating Policy for a Random Additional Service Facility

This paper studies the steady state behaviour of a Markovian queue wherein there is a regular service facility serving the units one by one. A search for an additional service facility for the service of a group of units is started when the queue length increases to K (0 < K < L), where L is the maximum waiting space. The search is dropped when the queue length reduces to some tolerable fixed size L - N. The availability time of an additional service facility is a random variable. The model is directed towards finding the optimal operating policy (N,K) for a queueing system with a linear cost structure.     

考虑即时采购价格的物流服务供应链优化

物流服务市场的不确定性会影响物流服务供应链的服务水平和收益。在考虑随机即时采购价格以及基础物流提供商在正常情况和应急情况下具有不同物流能力投资成本的情形下,引入期权机制研究不确定市场环境下物流服务供应链的优化决策,以提高物流服务供应链柔性和降低市场不确定性带来的风险。构建物流服务供应链的期权契约模型,采用Stackelberg博弈理论和优化算法分析和求得物流服务集成商的最优期权采购和即时采购策略,以及基础物流提供商的最优物流能力投资策略。结果表明即时采购价格将影响基础物流提供商和物流服务集成商的决策。最后通过数值分析研究即时采购价格的不确定程度对物流服务集成商和提供商的优化策略和利润的影响。     

电信运营商双寡头定价机制设计

电信市场存在运营商之间的竞争关系,运营商针对异质性消费者的定价机制设计更是直接影响其利润的实现,本文利用机制设计方法,分析了电信运营商的双寡头垄断定价策略,研究发现:(1)运营商的核心利润来源于低类型消费者的总剩余。低类型消费者的消费扭曲来源于运营商提供给高类型消费者过高的信息成本。要想改善低类型消费者的不满和消费扭曲,需要降低对高类型消费者的优惠幅度。(2)电信运营商的最优定价随竞争对手的价格同向变动。(3)电信运营商最优定价与消费者对该运营商的服务体验成正比,与消费者对竞争对手运营商的服务体验成反比。所以,运营商应当不断优化自己网络的服务质量,提高消费者的服务体验,进而才能有涨价的空间。     

Optimal Base Station Positioning and Channel Assignment for 3G Mobile Networks by Integer Programming

In this paper, discrete mathematical programming approaches are used to solve the frequency allocation and cell site selection problem in an integrated setup. Both CDMA (code division multiple access) and FD/TDMA (frequency/time division multiple access) technologies will be important for 3rd generation mobile systems. If all users share the same bandwidth, base transmitter stations should be placed such that a maximum of traffic can be carried at low interference rates. The expected traffic is represented by spatially scattered weighted nodes. The problem to select an optimal set of base station locations from a given pool of configurations is formulated as an integer linear program and solved by combinatorial optimization methods. For systems which employ FD/TDMA schemes, the cell site optimization process depends on the assignment of channels. We suggest an integrated linear programming approach to solve both objectives in a single planning step. Because of the problems' tremendous complexity, special branch-and-bound procedures are developed as exact and approximate solution methods. An examples is given for a typical urban scenario with base transmitters below roof tops.     

一个修理工的M/M/N可修排队的可靠性分析

本文研究了有一个修理工的 ,服务台忙时与闲时故障率不同的M/M/N可修排队的可靠性问题 ,本文给出关于有效服务台数的稳态分布的方程组 ,分析了当N =1时和 ξ1 =ξ2 时两个特例 ,所得结果与文献 [2 ]结果一致 .     

条件免运费的B2C平台商最优凑单推荐服务水平策略

在条件免运费(CFS)下,针对消费者基础运费和凑单异质性购物偏好,选择合理的购物凑单推荐服务水平策略是提升B2C平台商业绩的关键。在对平台商与消费者间的主从博弈关系、消费者效用函数关系分析基础上,通过构建Stackelberg博弈模型,揭示平台商凑单推荐服务水平和消费者购物意愿间的互相关系,进而针对消费者基础运费和凑单偏好,探究基础运费、保留价格和推荐商品价格对平台商最优购物推荐服务水平策略的影响。研究表明:不同的基础运费和消费者偏好对平台商利润的影响具有差异性;适度提升最优购物凑单推荐服务水平能有效提高消费者购物意愿、增加平台商利润。因此,基础运费、CFS阈值和凑单推荐服务水平的科学制定对平台商业绩改善具有重要影响。     

基于排队的库存服务系统最优控制策略

研究一个连续盘点的(s,Q)补货的库存服务系统。基于排队理论建立库存水平状态平衡方程,并推导出库存水平稳态概率分布以及作为库存控制的系统稳态性能指标。以库存成本最小化为目标,构建服务水平约束的库存控制模型。针对模型的非线性约束与整数型变量的特征,采用一种改进的遗传算法(IGA)用于决策变量的寻优。数值实验表明,当目标服务水平大于库存系统内生的服务水平时,实施服务水平约束能够降低库存控制成本。     

The Siting of Fire Stations

Perhaps the most important decision facing any Chief Fire Officer is how many fire stations to have and on which sites to build them. It is appreciated that the optimum solution is that which minimizes the sum of the financial loss from fire and the cost of providing the fire brigade. Financial loss data are not as yet available so the criteria for optimization have had to be altered.A technique has been evolved which minimizes the total number of fire appliance journey times to fires for any given number of fire stations. A set of solutions is obtained giving the best combination of r station sites from a set of n alternative sites, where r varies from n-1 to 1. This technique has been applied to the area covered by Bristol Fire Brigade and the results are discussed.Although the criterion adopted for optimization was necessarily unsatisfactory a near valid set of answers appears to have been obtained. Suggestions for future work are also made.     

地铁车站的客流模拟

本文以上海地铁车站（一号线）结构设计图为基础，对车站乘客流动状况建立随机模型，产生车站建成运行后乘客流动情况的模拟图形，从而验证车站设计的合理性，并可辅助车站设计。     

服务管理目标优化配置的Fuzzy-QFD线性规划模型构建与求解

由于服务管理的复杂性和模糊性,现有方法难以有效解决基于主观语言评价的服务质量改进问题。本文拓展了质量功能展开(QFD)方法在服务业中的应用,通过构建一个模糊线性规划模型,以求解最大化提高顾客需求综合满意度的企业能力优化配置问题。首先基于顾客感知-期望差距的模糊评估确定顾客需求、需求权重和边界约束等模型参数,接着运用模糊线性回归和非对称三角模糊数的隶属函数,将含有模糊变量的模糊线性规划问题转化为经典线性规划问题,进而求得不同模糊条件下的模型解。最后通过网购平台的实例验证了模型的有效性和可行性。