Designing and pricing menus of extended warranty contracts

Extended warranties provide “piece of mind” to a consumer in that product failures which occur after the base warranty expires are rectified at little or no cost. They also provide an additional source of revenue for manufacturers or third‐party providers, such as retailers or insurance providers, and help cultivate consumer loyalty. In this article, we analyze a number of extended warranty contracts which differ in design, including restrictions on deferrals and renewals. With the use of dynamic programming, we compute the optimal strategy for a consumer with perfect information and determine the optimal pricing policy for the provider given the consumer's risk characterization. We also provide insight into when different contracts should be issued. Finally, we illustrate how profits can be dramatically increased by offering menus of warranty contracts, as opposed to stand alone contracts, with the use of integer programming. Surprisingly, risk‐taking consumers provide the greatest benefit to offering menus. These insights can help a company develop a comprehensive warranty planning strategy for given products or product lines. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009     

基于系统动力学的协同决策模型性能分析

为探索信息化作战中指挥控制关键因素，提出改进作战指挥体制的对策措施，采用系统动力学理论，对协同决策的结构、参与者和信息反馈关系等关键因素进行了分析，在此基础上构建了基于系统动力学的协同决策模型并进行了模拟仿真。结果表明，增加指挥控制机构之间的信息共享可以有效提升协同决策的效率，为建立协同决策指挥控制体制提供了借鉴意义。     

试论翻译与向国外弘扬中华文化

弘扬中华文化包括在国内弘扬和向国外弘扬，二者不能偏废。本文将就后者进行论述。论述内容包括翻译的重要性、”中国文化欠缺型失语症”与译者的素质、文化交流的意义。向外弘扬中国文化既有利于本民族文化的发展，又有利于全人类文化的发展，甚至关系到人类的未来。要向外弘扬中华文化，翻译工作者首先要深谙中华文化。     

Dynamic institutionalization: the foundations of Japan’s radioactive problem

Many have suggested that the true purpose behind Japan’s development of a closed nuclear-fuel cycle is to maintain the technical potential to develop nuclear weapons. However, closer examination of the development of Japan’s nuclear industry shows that, although Japan possesses advanced nuclear technologies, there has been no deliberate strategy to create a nuclear-weapon option. There is no “nuclear hedge.” To illustrate this point, this article presents a framework called “dynamic institutionalization” to explain the origins of Japan’s nuclear policies and the different sets of institutionalized pressures and constraints that have perpetuated these policies over time. Japan’s continued development of closed fuel-cycle technologies is primarily driven by domestic politics and the lack of a permanent spent-fuel management solution. On the other hand, Japan’s institutionalized nuclear forbearance is driven by the calculation that, as long as US extended deterrence remains credible, Japan’s security is best guaranteed through reliance on the US nuclear umbrella. By analytically untangling the policy of closed fuel-cycle development from the rationale for nuclear forbearance, this article provides a more nuanced view of the relationships between the domestic and international variables shaping Japan’s nuclear policies.     

Military Spending,Conflict and External Debt in Sub-Saharan Africa

The damaging economic effects of the debt crises on Africa in the late 1980s encouraged considerable research on the determinants of external debt in developing economies. Although sub-Saharan Africa's (SSA) debt was cut by two-thirds by 2008, through two debt relief programmes, debt in the region has since been rising at an increasingly rapid pace. This study provides an empirical analysis of the determinants of external debt in SSA over the period 1960–2016, using dynamic panel methods. It also considers two potentially important factors that have received relatively little attention. One is military spending, rarely considered, despite a number of well-publicised scandals over the procurement of unnecessary and expensive high-tech weapons systems. A second, is the possibility that the countries studied have been involved in conflict. The empirical results point to a positive impact of military spending on external debt, but with some evidence of heterogeneity across the countries. Furthermore, findings indicate that the positive effect of military expenditure on debt becomes more marked in countries that have been affected by conflict. These results imply that policies to improve security and reduce military spending could be beneficial in reducing external debt and, potentially, improving economic performance in the region.     

Natural gas storage valuation and optimization: A real options application

In this article, we present an algorithm for the valuation and optimal operation of natural gas storage facilities. Real options theory is used to derive nonlinear partial‐integro‐differential equations (PIDEs), the solution of which give both valuation and optimal operating strategies for these facilities. The equations are designed to incorporate a wide class of spot price models that can exhibit the same time‐dependent, mean‐reverting dynamics, and price spikes as those observed in most energy markets. Particular attention is paid to the operational characteristics of real storage units. These characteristics include working gas capacities, variable deliverability and injection rates, and cycling limitations. We illustrate the model with a numerical example of a salt cavern storage facility that clearly shows how a gas storage facility is like a financial straddle with both put and call properties. Depending on the amount of gas in storage the relative influence of the put and call components vary. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009     

多轴越野车辆悬架部件结构优化设计

基于有限单元法、变密度方法和车辆动力学分析方法,对某型多轴越野车辆的典型部件(前悬架摆臂)主体进行了结构优化设计研究。结果表明:通过结构优化,降低了摆臂的质量,提高了摆臂的静态、动态结构刚度和强度。     

视景仿真中运动实体的动态碰撞检测

在视景仿真中,经常会出现运动实体穿入或穿透其他实体的现象,而用现有的各类包围盒模型不能很好地处理这一问题。为了解决这个问题,介绍了包围盒方法,分析了实体平动、转动、组合运动及相应包围盒的碰撞检测;针对所发现的问题,提出动态碰撞检测方法,并建立了运动实体的动态碰撞检测模型;运用OpenGVS图形引擎,通过VC++编程对模型进行了仿真,通过对仿真结果的对比实验,验证了模型的可行性。     

水下缩比航行体热尾流的红外探测实验

根据缩比模型,建立缩比红外成像实验测试系统,对水下航行体的体积、航行深度、运动速度、尾流排放等进行缩比设计,设计多种实验工况,可实现缩比目标模型红外尾流的静态和动态测试。一方面明确红外尾流的可探测性,另一方面掌握红外尾流可探测性的影响因素以及红外尾流的变化规律,为下一步工作奠定基础。缩比实验结果表明,利用区域灰度均值和均方差的起伏变化可有效探测水下航行体水面尾迹。     

基于梯形直觉模糊数的动态多准则群决策方法

针对决策信息为梯形直觉模糊数的多准则决策问题,引入含参得分函数和相关系数提出了一种动态多准则群决策方法,首先利用参照方案相关系数总偏差最小的非线性规划模型求解客观准则权重,通过参数因子转化犹豫度集结得到各方案综合得分函数,最后根据参数动态变化进行MATLAB仿真分析并排序。该方法适用于准则权重已知和未知的情形,弥补了犹豫度缺失和基于距离测度决策方法的缺陷,并通过航空装备保障合同商的选择决策实例验证了有效性。