Modeling and analysis of flexible queueing systems

We consider queueing systems with multiple classes of customers and heterogeneous servers where customers have the flexibility of being processed by more than one server and servers possess the capability of processing more than one customer class. We provide a unified framework for the modeling and analysis of these systems under arbitrary customer and server flexibility and for a rich set of control policies that includes customer/server‐specific priority schemes for server and customer selection. We use our models to generate several insights into the effect of system configuration and control policies. In particular, we examine the relationship between flexibility, control policies and throughput under varying assumptions for system parameters. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004     

模糊Petri网在故障诊断知识表示和推理中的应用

针对传统的模糊产生式规则知识表示复杂、推理效率低、单一阈值设定不能满足复杂故障诊断需求的问题,给出了模糊产生式规则转换为模糊Petri网的一般方法和故障诊断模型,以及基于双阈值设定的两级故障诊断推理算法,并将其应用于某型柴油机遥控系统故障诊断之中。通过设置双阈值提高了故障诊断的推理速度和推理效率,同时又能对系统的准故障状态进行检测,及时发现潜在故障,排除故障隐患。     

台湾制导武器发展剖析

台湾通过军购、仿制与自主研制 3种模式发展导弹武器,已拼凑起庞杂的导弹武器装备,并随着装备战略的变化,正在重点发展中远程精确打击能力。     

Network routing for insurgency: An adversarial risk analysis framework

Problems in counterterrorism and corporate competition have prompted research that attempts to combine statistical risk analysis with game theory in ways that support practical decision making. This article applies these methods of adversarial risk analysis to the problem of selecting a route through a network in which an opponent chooses vertices for ambush. The motivating application is convoy routing across a road network when there may be improvised explosive devices and imperfect intelligence about their locations. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

Production‐inventory systems with imperfect advance demand information and updating

We consider a supplier with finite production capacity and stochastic production times. Customers provide advance demand information (ADI) to the supplier by announcing orders ahead of their due dates. However, this information is not perfect, and customers may request an order be fulfilled prior to or later than the expected due date. Customers update the status of their orders, but the time between consecutive updates is random. We formulate the production‐control problem as a continuous‐time Markov decision process and prove there is an optimal state‐dependent base‐stock policy, where the base‐stock levels depend upon the numbers of orders at various stages of update. In addition, we derive results on the sensitivity of the state‐dependent base‐stock levels to the number of orders in each stage of update. In a numerical study, we examine the benefit of ADI, and find that it is most valuable to the supplier when the time between updates is moderate. We also consider the impact of holding and backorder costs, numbers of updates, and the fraction of customers that provide ADI. In addition, we find that while ADI is always beneficial to the supplier, this may not be the case for the customers who provide the ADI. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

Inventory control in divergent supply chains with time‐based dispatching and shipment consolidation

This article analyses a divergent supply chain consisting of a central warehouse and N nonidentical retailers. The focus is on joint evaluation of inventory replenishment and shipment consolidation effects. A time‐based dispatching and shipment consolidation policy is used at the warehouse in conjunction with real‐time point‐of‐sale data and centralized inventory information. This represents a common situation, for example, in various types of vendor managed inventory systems. The main contribution is the derivation of an exact recursive procedure for determining the expected inventory holding and backorder costs for the system, under the assumption of Poisson demand. Two heuristics for determining near optimal shipment intervals are also presented. The results are applicable both for single‐item and multiitem systems. © 2011 Wiley Periodicals, Inc. Naval Research Logistics 58: 59–71, 2011     

面向片上网络的多播吞吐率和能量模型

片上网络逐渐成为片上众核中非常有前景的互连方式.基于目录的cache一致性协议的维护需要片上互连网络高效的支持多播.在借鉴单播的网络吞吐率模型基础上,建立了面向多播的网络吞吐率模型和体系结构级的能量模型.相对于传统的多播路由算法,负载平衡维序路由算法(BDoR)和最小路径维序路由算法(MPDoR)通过平衡X和Y两个方向...     

求最大数目不相交多约束QoS路由的一种新方法

针对多约束QoS路由问题中从资源点到目的点的最大数目的不相交路由,文章给出了一种基于罚函数与整数规划的求满足QoS约束的最大数目的互不相交路由算法。该算法利用了路由模型的结构特性,使整数规划问题转化为线性规划问题,初步的算例表明算法是有效的。     

初始和终止库存不为零的生产与库存问题

针对初始库存和终止库存不为零的生产与库存问题,通过适当设置需求量,将其化为初始库存和终止库存为零的问题,以便应用重生性质进行求解。     

绿洲农业清洁生产初探

兵团农业是兵团国民经济的基础。随着兵团各农牧团场生产集约化程度不断提高,化肥、农药等在农业生产中大量投入及农业生产技术的不合理使用,使农业生态环境污染日趋严重,改善农业生产技术,推广农业清洁生产(即利用对环境友好的“绿色”化肥、“绿色”农药、“绿色”薄膜)是兵团农业可持续发展的方向。