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301.
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  相似文献   
302.
In this study, we analyze the joint pricing and inventory management during new product introduction when product shortage creates additional demand due to hype. We develop a two‐period model in which a firm launches its product at the beginning of the first period, before it observes sales in the two periods. The product is successful with an exogenous probability, or unsuccessful with the complementary probability. The hype in the second period is observed only when the product is successful. The firm learns the actual status of the product only after observing the first‐period demand. The firm must decide the stocking level and price of the product jointly at the beginning of each of the two periods. In this article, we derive some structural properties of the optimal prices and inventory levels, and show that (i) firms do not always exploit hype, (ii) firms do not always increase the price of a successful product in the second period, (iii) firms may price out an unsuccessful product in the first period if the success probability is above a threshold, and (iv) such a threshold probability is decreasing in the first‐period market potential of the successful product. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 304–320, 2015  相似文献   
303.
Abstract

Smart power is comprised of two elements: the quest for building society among states and between states and non-state actors; as well as the desire for cleaner forms of power projection. This special issue explores how states continue to fumble over achieving the optimum mix of hard and soft power across several country cases and themed articles. This set of contributions suggests that smart power is not unlike a ‘Swiss Army Knife’ analogy: multifunctional and challenging to choose the right combination of ideational and material tools.  相似文献   
304.
故障预测和健康管理(PHM)技术具有故障诊断、故障预测以及健康管理的功能,对降低火控装备维修成本、增强火控系统的完备性以及提高火控系统管理效率具有重要意义。根据通用火控系统发展现状及应用需求,将PHM技术引入到火控系统中。首先介绍了PHM技术原理和国内外发展现状,重点讨论了PHM关键技术和通用火控系统PHM体系结构。最后展望了火控系统PHM技术的发展趋势。  相似文献   
305.
在利用三端集成式稳压器LMH317构成直流稳压电源的基础上,添加由固态继电器阵列控制导通的高精度电阻,通过计算进行合理取值。由主控制器FPGA执行上位机指令,实现稳压器输出端电压大小调整。继电器AQY210具有电气开关特性,且内阻较小,对输出电压精度影响较小,通过对输出电压的正确标定,使其具有输出范围宽,精度高的优点,能够满足现代工业发展对能源供给装置的需求。  相似文献   
306.
提出了一个分布式的基于品质度量的分层密钥优化管理机制。该机制通过动态选择高品质的节点作为PKG来增强移动Ad Hoc网络的安全性,并将网络生存时间最大化。节点的选择可以归结为随机(restless bandit)问题,并且将密钥更新过程分为在线和离线两个部分,从而降低了计算复杂性。仿真结果表明,该机制可增强网络的安全性和将网络生存时间最大化,非常适合移动自组网的应用要求。  相似文献   
307.
Although soft power is now seen as an indispensable foreign policy tool, its efficacy has rarely been put to a rigorous empirical test. Using data from HARMONIOUS MISSIONs 2010, 2011 and 2013, this article seeks to examine the degree to which the soft power engagement missions of the Chinese hospital ship, the Peace Ark, has advanced Chinese interests. Although any conclusions drawn must be considered preliminary, as so little time has passed between the ship's visits and the current analysis, this research indicates that these missions’ impact on advancing Chinese interests was at best limited. Although observations from a single set of cases are unlikely to settle the debate between soft power advocates and detractors, it is hoped that this research will serve as a catalyst to further empirically based research on this topic.  相似文献   
308.
为了改善补偿电流跟踪控制性能,在分析比例谐振控制策略原理与特性的基础上,结合指令电流的特性,合理地融入重复控制,提出了一种基于多重化坐标系的比例谐振重复控制策略。仿真和实验结果表明:该控制策略具有优良的动静态性能,可有效抑制电流的谐波。  相似文献   
309.
针对舰船装备维修保障领域维修保障知识缺乏有效统一管理、共享和重用程度低等问题,将领域本体理论引入维修保障知识管理中,提出了基于全寿命周期的舰船装备维修保障知识本体建模方法。分析舰船装备维修保障领域知识的来源、分类和构成,构建了装备维修保障领域的顶层本体及其概念关系。重点介绍了维修保障知识中故障案例知识的本体建模表示,并提出了基于预检索的全局故障案例知识检索算法,建立了原型系统并应用验证。结果表明:该方法能够解决目前维修保障知识管理中存在的问题,提高了知识检索效率。  相似文献   
310.
对于Cerenkov型器件,由高频结构温升引发的热脱附会造成的射频击穿,进而导致输出功率降低和脉冲缩短。基于此,研究了电磁脉冲对高频结构的加热温升效应,推导了高频结构的温升公式,指出了理论公式的适用范围,并给出了数值求解试件温升的方法。以二周期1 MV·cm-1的高频结构为例,进行了温升的数值计算和仿真研究。结果表明,脉宽100 ns的单脉冲对不锈钢试件的温升效应明显高于其他材料。当系统工作在高重频时,电磁脉冲的温升作用可能使金属材料达到气体脱附的阈值从而引发气体脱附形成局部高压。该研究可为高功率微波源中的气体脱附以及射频击穿等研究提供参考。  相似文献   
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