民用卫星电视天线的直径计算与跟踪

介绍了从一个已知的民用或国际通信卫星成功地接收到电视图像时,所需天线口径的计算式和利用抛物面天线如何跟踪太空中卫星的知识。     

毕业生分配规划模型初探

本文阐述系统工程方法在上海市1987—1990年大学毕业生分配规划中的应用。通过建立数学模型及其形式变换,给出了两种不同的运算结果,并根据综合指标分别对结果进行了分析和评价。分析结果表明,推荐方案的总体偏差只有原方案的五分之一。     

形成函数在溶液平衡研究中的应用

本文从广义上对形成函数进行了定义,并深入研究了它在溶液平衡中的应用。     

Efficient Algorithms for Determining 3-D Bi-Plane Imaging Geometry

Biplane projection imaging is one of the primary methods for imaging and visualizing the cardiovascular system in medicine. A key problem in such a technique is to determine the imaging geometry (i.e., the relative rotation and translation) of two projections so that the 3-D structure can be accurately reconstructed. Based on interesting observations and efficient geometric techniques, we present in this paper new algorithmic solutions for this problem. Comparing with existing optimization-based approaches, our techniques yield better accuracy and have bounded execution time, thus is more suitable for on-line applications. Our techniques can easily detect outliers to further improve the accuracy.This research was supported in part by NIH under USPHS grant numbers HL52567.     

原子簇的合成方法、性质表征与结构

利用给电子有机和无机配位体的交换反应和金属卤化物与羰基金属阴离子的复分解反应,合成异核原子簇具有反应条件温和易于控制,收率较高的特点。本文描述Fe_3(CO)_9(C_2H_2)_3等11个原子簇的合成方法,配位状态与簇核的结构。     

战略联盟的不完全性分析

环境的不确定性使得当前战略联盟条件变得很复杂,而不完全合同理论为分析战略联盟提供了新的视角.本文在Hart的企业边界模型中加入机会主义行为因素,构建出联盟边界模型;通过博弈分析方法,进一步探讨了多种情况下机会主义行为对联盟边界变化(即联盟不完全性)的影响.     

Dynamic Assignment of Flexible Service Resources

Resource flexibility is an important tool for firms to better match capacity with demand so as to increase revenues and improve service levels. However, in service contexts that require dynamically deciding whether to accept incoming jobs and what resource to assign to each accepted job, harnessing the benefits of flexibility requires using effective methods for making these operational decisions. Motivated by the resource deployment decisions facing a professional service firm in the workplace training industry, we address the dynamic job acceptance and resource assignment problem for systems with general resource flexibility structure, i.e., with multiple resource types that can each perform different overlapping subsets of job types. We first show that, for systems containing specialized resources for individual job types and a versatile resource type that can perform all job types, the exact policy uses a threshold rule. With more general flexibility structures, since the associated stochastic dynamic program is intractable, we develop and test three optimization‐based approximate policies. Our extensive computational tests show that one of the methods, which we call the Bottleneck Capacity Reservation policy, is remarkably effective in generating near‐optimal solutions over a wide range of problem scenarios. We also consider a model variant that requires dynamic job acceptance decisions but permits deferring resource assignment decisions until the end of the horizon. For this model, we discuss an adaptation of our approximate policy, establish the effectiveness of this policy, and assess the value of postponing assignment decisions.     

An approximation algorithm for the <Emphasis Type="Italic">k</Emphasis>-level capacitated facility location problem

We consider the k-level capacitated facility location problem (k-CFLP), which is a natural variant of the classical facility location problem and has applications in supply chain management. We obtain the first (combinatorial) approximation algorithm with a performance factor of \(k+2+\sqrt{k^{2}+2k+5}+\varepsilon\) (ε>0) for this problem.     

我国旅游信用消费发展缓慢的原因与改善的对策

旅游消费已成为我国重要的消费热点之一,但旅游信用消费却在我国发展缓慢.文章阐述了旅游信用消费的概念和特点,分析了其发展现状,从旅游信用消费主体和信用消费环境两方面分析了制约我国旅游信用消费发展的原因,并就这些原因提出了相应的对策.     

农村微观组织再造与社区自我整合——湖北省杨林桥镇农村社区建设的经验与启示

长期沿袭的自上而下单一行政治理体制的一个重要缺陷是,外部性的整合机制一旦发生变化,乡村没有相应的组织来承接和应对大量农村内部公共事务,进行自我整合,从而陷于“治理真空”。由此需要重新构造农村微观组织体系,大力推动乡村社区民间组织的发育,使之成为新农村建设的重要组织载体。湖北省杨林桥镇通过农村社区建设促进农村公益事业的管理和自我整合的事例,说明社区自我整合可以将村民的动员式参与变为主动式参与,开发农村内部资源和节省治理成本。对于正在变化中的农村来说,外部性国家整合与社区自我整合都是不可或缺的。