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41.

Within the EU France devotes to defence the largest financial and human resources although it is not the richest country, nor has it the largest population or labour force. The cost of nuclear weapons accounts for only a small fraction of this abnormally high French defence effort. If France had restructured its military capabilities at the same rate as its principal Allies during the 1985–1994 period, then French defence outlays would be about 20% less than at present. The fundamental reasons for France's excess defence outlay comprise virtual total dependence on French sources for equipment, produced in very small numbers; a military presence outside of Europe; and too many personnel. These deficiencies, and the consequent absence hitherto of a “peace dividend”, indicate a failure to identify the country's real strategic requirements, and a lack of will to reorganise efficiently French defence. The recently announced reform towards an all‐professional force is unlikely to achieve the potential and desirable improvement in cost‐effectiveness.  相似文献   
42.
Croatia's successful bid for independence was one of the defining moments of the immediate post-Cold War period. Nevertheless, the means that Croatia used to obtain independence remains relatively unexamined by academics. This article focuses on the early period of Croatia's bid for secession, and specifically the role that Yugoslavia's policy of Total National Defence played in facilitating its independence. Unlike in Slovenia, where the legacies of Total National Defence facilitated Slovenia's bid for secession, in Croatia the decision of its political leaders meant that the country largely neglected its positive legacies, resulting in a protracted four-year struggle.  相似文献   
43.
公安消防部队开展基地化模拟训练是适应新职能任务、提升灭火救援实战能力、研究和检验各类战术战法的需要.分析了当前公安消防部队开展基地化模拟训练“软、硬”件建设不到位、标准执行不到位、训练设施利用率不高、训练效果不明显、人员集中难,以及后勤保障难落实等问题,提出了解决影响和制约基地化模拟训练深入开展的对策与措施.  相似文献   
44.
采用高低温运动粘度测定仪测量PAO8(8#聚烯烃)合成基础油和45#变压器油基础油按不同比例调和后混合基础油的粘温性能,运用Arrhenius模型和Grunberg-Nissan模型计算混合基础油的理论粘度,研究粘度偏差率随测试温度的变化规律.实验结果表明:Arrhenius模型能准确预测混合基础油的高温运动粘度,粘度偏差率最大值不超过1%,而Grunberg-Nissan模型能精确计算混合基础油的低温运动粘度;PAO8和45#变压器油基础油调和能够获得高低温粘度的匹配.  相似文献   
45.
A combination of threat analysis and “subterranean forces” (such as proclivities to fight conventional wars as compared to asymmetric ones) leads the USA to prefer focusing on the threats from China rather than those emanating from the Middle East.  相似文献   
46.
针对工程中查找四连杆机构连杆曲线图谱所存在的精度及效率问题,提出一种利用计算机图形学和数据库原理进行连杆曲线快速识别和查找的方法,此方法的核心是建立起曲线与机构的对应关系,用适当的数据结构表示它们,从而快速识别连杆曲线并建立相应的数据库,该方法还能迅速实现机构的反求。  相似文献   
47.
We consider a two‐echelon inventory system with a manufacturer operating from a warehouse supplying multiple distribution centers (DCs) that satisfy the demand originating from multiple sources. The manufacturer has a finite production capacity and production times are stochastic. Demand from each source follows an independent Poisson process. We assume that the transportation times between the warehouse and DCs may be positive which may require keeping inventory at both the warehouse and DCs. Inventory in both echelons is managed using the base‐stock policy. Each demand source can procure the product from one or more DCs, each incurring a different fulfilment cost. The objective is to determine the optimal base‐stock levels at the warehouse and DCs as well as the assignment of the demand sources to the DCs so that the sum of inventory holding, backlog, and transportation costs is minimized. We obtain a simple equation for finding the optimal base‐stock level at each DC and an upper bound for the optimal base‐stock level at the warehouse. We demonstrate several managerial insights including that the demand from each source is optimally fulfilled entirely from a single distribution center, and as the system's utilization approaches 1, the optimal base‐stock level increases in the transportation time at a rate equal to the demand rate arriving at the DC. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
48.
An important aspect of supply chain management is dealing with demand and supply uncertainty. The uncertainty of future supply can be reduced if a company is able to obtain advance capacity information (ACI) about future supply/production capacity availability from its supplier. We address a periodic‐review inventory system under stochastic demand and stochastic limited supply, for which ACI is available. We show that the optimal ordering policy is a state‐dependent base‐stock policy characterized by a base‐stock level that is a function of ACI. We establish a link with inventory models that use advance demand information (ADI) by developing a capacitated inventory system with ADI, and we show that equivalence can only be set under a very specific and restrictive assumption, implying that ADI insights will not necessarily hold in the ACI environment. Our numerical results reveal several managerial insights. In particular, we show that ACI is most beneficial when there is sufficient flexibility to react to anticipated demand and supply capacity mismatches. Further, most of the benefits can be achieved with only limited future visibility. We also show that the system parameters affecting the value of ACI interact in a complex way and therefore need to be considered in an integrated manner. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
49.
针对BOM概念模型重用的问题,提出了概念模型相似度用于描述两个概念模型之间的相似程度.并提出相似度评估算法用于计算概念模型之间的相似度.根据概念模型的定义,将相似度的计算归结为名字相似度计算和最优匹配计算两个基本过程.研究了算法中接口权重参数和行为权重参数的不同组合对算法查准率和查全率的影响.通过对JC3IEDM数据模...  相似文献   
50.
针对某数字化火控系统实时故障检测与诊断问题,提出了一种基于对象式框架知识表示的火控系统实时故障诊断方法。该方法采用专家系统与实时进程通信,获取故障征兆,进行实时推理定位故障源。给出了诊断系统的一般架构,介绍故障诊断系统知识表示的形式化描述,实时推理、规则匹配算法和UDP进程通信协议。实际应用证明了这种方法的有效性和可扩展性。  相似文献   
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