Scheduling with centralized and decentralized batching policies in concurrent open shops

This article considers batch scheduling with centralized and decentralized decisions. The context of our study is concurrent open shop scheduling where the jobs are to be processed on a set of independent dedicated machines, which process designated operations of the jobs in batches. The batching policy across the machines can be centralized or decentralized. We study such scheduling problems with the objectives of minimizing the maximum lateness, weighted number of tardy jobs, and total weighted completion time, when the job sequence is determined in advance. We present polynomial time dynamic programming algorithms for some cases of these problems and pseudo‐polynomial time algorithms for some problems that are NP‐hard in the ordinary sense. © 2010 Wiley Periodicals, Inc. Naval Research Logistics 58: 17–27, 2011     

改进类电磁算法在武器目标分配问题中的应用

通过基于级数的粒子编码变换方法,将武器目标分配问题的约束条件进行了化简.对原始类电磁算法,在种群初始化、局部搜索、合力计算以及粒子移动等各步骤对其进行改造,使之适应武器目标分配问题的整数解空间.最后通过数值实验验证了该改造后算法解决武器目标分配问题的有效性.     

Using stochastic programming to solve an outpatient appointment scheduling problem with random service and arrival times

We study a stochastic outpatient appointment scheduling problem (SOASP) in which we need to design a schedule and an adaptive rescheduling (i.e., resequencing or declining) policy for a set of patients. Each patient has a known type and associated probability distributions of random service duration and random arrival time. Finding a provably optimal solution to this problem requires solving a multistage stochastic mixed‐integer program (MSMIP) with a schedule optimization problem solved at each stage, determining the optimal rescheduling policy over the various random service durations and arrival times. In recognition that this MSMIP is intractable, we first consider a two‐stage model (TSM) that relaxes the nonanticipativity constraints of MSMIP and so yields a lower bound. Second, we derive a set of valid inequalities to strengthen and improve the solvability of the TSM formulation. Third, we obtain an upper bound for the MSMIP by solving the TSM under the feasible (and easily implementable) appointment order (AO) policy, which requires that patients are served in the order of their scheduled appointments, independent of their actual arrival times. Fourth, we propose a Monte Carlo approach to evaluate the relative gap between the MSMIP upper and lower bounds. Finally, in a series of numerical experiments, we show that these two bounds are very close in a wide range of SOASP instances, demonstrating the near‐optimality of the AO policy. We also identify parameter settings that result in a large gap in between these two bounds. Accordingly, we propose an alternative policy based on neighbor‐swapping. We demonstrate that this alternative policy leads to a much tighter upper bound and significantly shrinks the gap.     

信息知识库中的数据可用性恢复策略

信息知识库在工业生产中能够提高生产效率、降低资源消耗,但数据失效频率高。针对多节点失效重构的纠删码策略较少,且未充分考虑失效数据重构时各参与节点间的链路关系,导致重构效率较低。针对信息知识库数据失效,提出一种新的重构策略。根据节点的数据处理能力,选取数据处理能力最高的新生节点为路由节点;依据路由节点与候选供应节点及剩余空闲节点的链路带宽,确定供应节点及新生节点,从而构建数据重构网络拓扑,提高失效数据重构效率。实验结果证实,与传统纠删码策略性能比较,该方法有较短的重构时间和较高的重构成功率。     

网络靶场实训平台的规划与实践

网络靶场实训平台是以网络空间安全人才培养需要为目的建设的高逼真网络学习、训练和研究平台,是一种特殊类型的网络靶场.介绍了世界各国网络靶场的研究背景和网络靶场的概念,规划了网络靶场实训平台的总体架构,明确了平台的主体功能、主要模拟对象和具体建设要求.结合实际,细化了网络靶场实训平台的功能,对其具体应用效果进行了分析.网络靶场实训平台在高校人才培养中具有独特的应用优势和不可替代的作用,可在高校实验教学中推广应用.     

A platform for initial testing of multiple camouflage patterns

The human visual system is still an important factor in military warfare; military personnel receive training on effective search strategies, and camouflage that can effectively conceal objects and personnel is a key component of a successful integrated survivability strategy. Previous methods of camouflage assessment have, amongst others, used psychophysics to generate distinctiveness metrics. However, the population from which the human observers are drawn is often not well defined, or necessarily appropriate. In this experiment we designed a new platform for testing multiple patterns based on a camouflaged object detection task, and investigate whether trained military observers perform better than civilians. We use a two-alternative forced choice paradigm, with participants searching images of woodland for a replica military helmet displaying Olive Green, Multi Terrain Pattern, US Marine Pattern or, as a conspicuous control, UN Peacekeeper Blue. Our data show that there is no difference in detection performance between the two observer groups but that there are clear differences in the effectiveness of the different helmet colour patterns in a temperate woodland environment. We conclude that when tasks involve very short stimulus presentation times, task-specific training has little effect on the success of target detection and thus this paradigm is particularly suitable for robust estimates of camouflage efficacy.     

基于GIS的泥石流灾害系统中数据集成方案

为增强泥石流灾害数据可视化管理系统的兼容性,分析了多源数据集成技术,讨论了泥石流灾害工程中多来源数据和多格式数据的问题,以及在应用系统中对多源数据集成处理的要求,提出以SuperMap结合VC 6．0在基于GIS的泥石流灾害工程应用中实现多源数据集成的一种解决方案,实现了系统中对多来源、多格式数据的集成功能,从而达到了系统能直接访问、处理不同来源空间数据的目标。     

Exploiting the Challenges to Bioweapons Development

ABSTRACT

Widespread and often exaggerated generalizations about the global spread weapons of mass destruction (WMDs) have proven to be not only misleading and technologically naïve, but also unhelpful in formulating effective policies to counter their threat. The new book by George Mason University's Sonia Ben Ouagrham-Gormley dispels the popular narrative that governments and terror groups can easily—and inevitably will—develop WMDs, particularly biological weapons, by exploring the complex external and internal conditions that such programs require, as demonstrated by the Cold War-era biological weapon programs of the superpowers. This empirically grounded and realistic assessment of how states try—and often fail—to develop such programs offers a more reliable basis to craft realistic counterproliferation policies that can elicit international support.     

The United Nations-African Union Mission in Darfur: Implications and prospects for success

With the security situation in Darfur remaining grim, the international community passed United Nations Security Resolution 1769 that authorised a more robust peacekeeping force. This article addresses the security concerns motivating the United Nations-African Union Mission in Darfur (UNAMID), highlights the mandate and implications of the force, and compares the potential command and control issues to the experiences of the Somalia intervention in the 1990s. It closes by analysing the prospects for success of the intervention and offering some limited recommendations on ways to mitigate the risks associated with the peacekeeping effort.