Environmental regulation in project‐based industries

We study the environmental regulation of industrial activities that are organized as projects. Applications arise in construction, ship and aircraft building, and film making, among other industries. Relative to manufacturing, environmental regulation is different in project‐based industries, due to the uniqueness and geographical diversity of projects, and a lack of product takeback programs. Because the amount of waste and pollution generated by project companies can be large, regulators need environmental policies to ensure reduction of waste and pollution. We consider a regulator who attempts to maximize social welfare. We model this problem as a bilevel nonlinear program. The upper level regulator specifies waste reduction targets, which the lower level project companies meet using waste stream reduction and remediation of pollution, while attempting to control their project costs. We find that high waste diversion targets lead to outcomes with little pollution, but excessive project costs and only modest waste stream reduction. Projects that have lower task precedence density, or that have pollutants with different environmental impacts, show larger increases in project cost and time resulting from regulation. We describe a subsidy for waste stream reduction that coordinates the system, and we estimate the value of coordination. We also describe a bonus that encourages truthful reporting by project companies, and evaluate the relative cost and effectiveness of the subsidy and the bonus. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 228–247, 2015     

基于IDEA模型的坦克性能指标需求方案有效性分析

针对坦克车辆性能指标需求方案有效性分析的输入指标为区间数、具有模糊性这一实际情况,提出了一种基于IDEA模型的需求方案有效性分析方法,并详细给出了该方法的计算步骤和算法。研究表明,该方法能够有效完成需求方案的有效性分析,同时也简化了计算过程,使得分析结果更为客观合理,最后通过一个示例来验证模型的可行性和有效性。     

“小机构”的“大智慧”——美国高能激光技术联合办公室

美国国防部在世纪伊始成立的高能激光技术联合办公室专职人员不到10人,却能高效调动创新体系中所有创新单元,长期保持战略先导地位。本文全面介绍联合办公室的使命职能、编制组成、运行方式、科研项目、代表性成果以及重要决策,旨在为技术创新和管理创新提供参考和借鉴。     

基于改进LMS算法的复合材料超声检测缺陷识别

在径向基函数（RBF）神经网络实现无人机复合材料超声检测脱粘缺陷识别时,针对最小均方（LMS）算法在确定网络输出权值时存在稳态失调误差和收敛速度相矛盾的问题,提出一种改进的自适应的变步长LMS算法．该算法根据反馈误差自适应确定步长,通过引进动量项加快收敛速度．将改进LMS算法应用到RBF网络缺陷识别中,结果表明该方法在稳态失调误差较小的情况下,能快速确定RBF网络的权值．改进的RBF网络能够较好地识别超声检测脱粘缺陷．     

一种由条件确定导引时机的线导鱼雷导引方案

基于对水下平台获取目标信息客观实际的分析,指出以固定的导引周期、自动实现线导鱼雷整个过程的导引是难以实现的.为此,线导鱼雷导引方案设计必须综合利用各种渠道所获得的目标信息资源和鱼雷的高速制资源,才能大幅提高线导鱼雷的使用性能.通过仿真研究提出:“由条件确定导引时机”的概念,给出利用“依赖条件调度的管理器”对来自各方面的目标方位进行优先级排序并控制导引算法调度时机的技术方法;利用“间断导引”兼顾导引平台听测与鱼雷快速接近目标之矛盾的技术方案,给出了确定“听测速度”、转换方法和转换时间间隔的技术方法和途径.     

不确定环境下装备采购项目组织结构评估研究

首先分析了装备采购项目组织结构柔性的概念、环境不确定性的主客观因素及组织结构柔性与环境不确定性匹配的涵义;其次提出了装备采购项目组织结构柔性与环境不确定性的评价指标体系和测度方法,并在此基础上设计了组织结构柔性与环境不确定性匹配度的计算方法及判断准则;最后给出了算例。     

论工程款和民工工资拖欠问题产生的原因及对策

文章就工程款和民工工资拖欠问题产生的原因及对策作了系统分析,认为从源头上抓起和管起、从环节上把关控制、从全过程监督和防范、从企业自身规避和降低风险、从法律上寻求保障和途径,来有效解决工程款和农民工工资的拖欠问题。     

型号项目工期风险管理决策模型与自适应遗传算法

针对型号项目的过程特点,建立了型号项目工期风险的管理决策模型。模型考虑了型号项目中活动重叠、活动迭代、活动执行时间的不确定性和可更新资源总量等重要的工期风险影响因素。从模型的特点出发,给出了问题求解的基于自适应遗传算法的仿真优化方法。算例显示,该算法能较好地求解本文的工期风险管理决策问题。     

基于动量BP神经网络的确定掩护重点问题研究

确定掩护重点是地面防空作战的一个重点和难点问题。通过分析影响确定掩护重点问题的主要因素,建立评价指标体系,利用动量BP神经网络解决了确定掩护重点的评价模型,并采用MATLAB6.5的神经网络工具箱进行仿真实现。方法较好地降低主观误差,为确定被掩护目标重要性排序和兵力分配提供了依据。通过对BP算法的改进,减少了误差,提高了学习速度。模型思路清晰,算法简单实用,较好地解决了防空兵辅助决策系统智能确定掩护重点目标的问题。     

A metaheuristic scheduling procedure for resource-constrained projects with cash flows

Resource-constrained project scheduling problems with cash flows (RCPSPCF) are complex, combinatorial optimization problems. Many heuristics have been reported in the literature that produce reasonable schedules in limited project environments. However, the lack of a heuristic that dominates under differing project conditions can lead to a suboptimal choice of an appropriate heuristic for scheduling any given project. This may result in poor schedules and monetary losses. This paper reports on the application of the tabu search metaheuristic procedure for the RCPSPCF. Strategies for neighborhood generation and candidate selection that exploit the special features of the problem are combined with a simple multiheuristic start procedure. Extensive experimentation, with multiple data sets and comparison with an upper bound, indicates a significant improvement, both in project Net Present Value (NPV) as well as the number of projects, where the metaheuristic outperforms the best known heuristics in the literature. More specifically, this procedure produces the best schedules in over 85% of the projects tested, in contrast to the best single-pass heuristics which have been shown to dominate in at most 20% of the same cases. This iterative, general purpose heuristic is able to adapt significantly better to the complex interactions of the many critical parameters of the RCPSPCF than single-pass heuristics that use more specific information about each project environment. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 912–927, 1999