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1.
The article focuses on both economics and spatial issues related to Maintenance Repair and Overhaul (MRO) of defence platforms in Europe. Using facts and figures related to costs, trends and fleet sizes evolution, the authors discuss the interest of a spatial reorganisation of MRO production. Given the fiscal situation of the main European countries with a modern army, the relevant scale to consider the reorganisation is certainly Europe. Through the example of defence helicopters fleets of a selection of European countries, the authors address the question of cooperation of the MRO. A greater cooperation in the support of fleets would lead to a spatial reorganisation of MRO. On one side economies can be expected from this reorganisation, but, on the other hand, new problems arise. Specifically, a number of costs associated with different forms of “distances” – geographical, operational and political distances – limit the potential savings that could be expected. This work provides insights on these important issues for the construction of a European defence, both in its political, military and industrial dimensions.  相似文献   

2.
The choice between balanced and specialized defence forces depends on the technology of defence output (e.g. whether a force scope multiplier is present), the existence of scope and scale economies, the platform customization costs and, of course, the level of defence budgets. Minimum force element levels (thresholds), and scale economies facilitate specialization as opposed to scope economies (e.g. platform‐sharing), scale diseconomies and the force scope multiplier (e.g. defence weakest‐link technology). When a balanced force is not optimal, the option value of a non‐optimally maintained force element must also include the opportunity cost arising from suboptimal force elements. Shrinking defence budgets may produce two surprising phenomena. If some force elements are shut down as a result of thresholds, the surviving ones may increase in platform numbers as well as enjoying closer‐to‐most‐desirable platforms. Furthermore, if heritage force elements are shut down within the budget contraction environment, overall defence capability might rise.  相似文献   

3.
李雯  何孟良  侯霞 《国防科技》2020,41(5):84-89
俄罗斯按照建设航天力量的需求,积极研究现代空天防御教学技术设备。俄罗斯空天防御教学训练设备可帮助受训者利用所获得的知识与能力,在准备和完成实践任务时在不同系统设备间实现不同级别的综合协同,将实现结构和软件的模块化。俄航天兵使用空天防御教学训练设备的经验对军队空天防御专业人员训练具有重要的借鉴意义。本文分析了俄罗斯空天防御教学训练设备现状,研究了朱可夫空天防御军事学院一体化空天防御自动化控制系统教学试验模型的构成、原理、作用和应用,总结了俄罗斯空天防御教学训练设备在国家标准、教学法、工效学和组织方面存在的主要问题及解决办法,以期为军队空天防御教学训练设备发展提供参考。  相似文献   

4.
The costs of many economic activities such as production, purchasing, distribution, and inventory exhibit economies of scale under which the average unit cost decreases as the total volume of the activity increases. In this paper, we consider an economic lot‐sizing problem with general economies of scale cost functions. Our model is applicable to both nonperishable and perishable products. For perishable products, the deterioration rate and inventory carrying cost in each period depend on the age of the inventory. Realizing that the problem is NP‐hard, we analyze the effectiveness of easily implementable policies. We show that the cost of the best Consecutive‐Cover‐Ordering (CCO) policy, which can be found in polynomial time, is guaranteed to be no more than (4 + 5)/7 ≈ 1.52 times the optimal cost. In addition, if the ordering cost function does not change from period to period, the cost of the best CCO policy is no more than 1.5 times the optimal cost. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.  相似文献   

5.
Most counterinsurgency campaigns have featured the use of some form of local defense forces. Such forces have had a somewhat mixed record, both in their usefulness in actually countering insurgents and in their longer-term impact on internal security. This article focuses on historical cases that provide lessons for the best operational and strategic uses of local defense forces and measures to control their activities.  相似文献   

6.
Defense industrial complexes in leading Cold War nations have downsized and reallocated resources to other productive activities in the 1990s. In this paper, we analyze the experience of two key countries ‐ the US and France. Comparing the two countries, we find similar outcomes in budgetary retrenchment and large firm restructuring but marked differences in the pace of downsizing and diversification among small and medium‐sized firms. We hypothesize that three sets of contextual differences may explain these differences: 1) institutional differences in the way that the State bureaucracies ‐ the Pentagon and the French Délégation générale pour l'armement (DGA) ‐ oversee defense industrial matters, 2) differences in military industry ownership and firm size patterns, and 3) differences in the regional distribution of defense industrial capacity and associated regional policies. In closing, we note that the two countries’ defense industrial complexes are becoming more alike and speculate on the significance of invidious competition and interactions between them. We address briefly the future of French/American arms industrial competition and cooperation, given the trend towards transnational security arrangements and defense industry globalization  相似文献   

7.
According to common wisdom, the Golan provides Israel with an ideal platform for its warning stations as well as the best available defense line against a massive Syrian ground attack. Challenging this belief, this article compares the present situation with an alternative defined by (a) a complete Israeli withdrawal from the Golan, (b) a complete demilitarization of the evacuated territory, and (c) considerable limitations on Syrian military presence in the area between the Golan and Damascus. The article reaches two conclusions. First, that a combination of means, primarily airborne and space‐based platforms, can effectively answer Israel's northern intelligence needs. Second, the security arrangements set above, combined with recent revolutionary military technologies and its relative advantage in this domain, offer Israel an effective ‐ in some respects even a better ‐ alternative, to the present defense line.  相似文献   

8.
本文基于双路由单元研究了SpaceWire总线的性能评价体系。研究中,首先给出了双路由单元的定义,推导了基于双路由单元的路由系统的数据传输时间和资源耗费的计算方法;其次推导了基于双路由单元的多路由拓扑系统的性能评价体系;然后采用蒙特卡洛模拟的方法建立了双路由单元系统的模拟平台,仿真计算了路由单元在不同接口配置情况下的性能。研究结果表明:基于双路由单元的传输时间和资源耗费指标能够评价SpaceWire总线的性能;并且在不同接口配置时,存在一种最佳的配置方式能够使得系统的性能达到最优。  相似文献   

9.
防空兵群阵地选择是防空兵力部署的前提条件,阵地选择与配置的正确与否是防空兵部队能否有效进行抗击敌空袭兵器的一个重要因素.在分析以往防空阵地优选方法不足的基础上,提出了基于改进的层次分析与集对分析的多因素优选方法,建立了防空兵群配置地域方案优选的模型.通过实例分析了影响防空兵群阵地选择的相关因素,确定了配置地域优选的指标体系,用三标度法确定指标因素的权重,以相对贴近度的大小对待选阵地进行优选和排序.该方法能够定性与定量相结合,模型简单规范,为防空兵群阵地优选提供了一种有效的方法和途径.  相似文献   

10.
分析了传统的统一调度下和电力市场环境下发电厂机组检修计划的不同,在此基础上提出不同于以往的检修计划方法。以检修费用、电价收益损失和违约金之和最小为目标函数,然后采用0-1整数规划的直接枚举法求解。最后通过算例论证了该方法的可行性。  相似文献   

11.
The parallel machine replacement problem consists of finding a minimum cost replacement policy for a finite population of economically interdependent machines. In this paper, we formulate a stochastic version of the problem and analyze the structure of optimal policies under general classes of replacement cost functions. We prove that for problems with arbitrary cost functions, there can be optimal policies where a machine is replaced only if all machines in worse states are replaced (Worse Cluster Replacement Rule). We then show that, for problems with replacement cost functions exhibiting nonincreasing marginal costs, there are optimal policies such that, in any stage, machines in the same state are either all kept or all replaced (No‐Splitting Rule). We also present an example that shows that economies of scale in replacement costs do not guarantee optimal policies that satisfy the No‐Splitting Rule. These results lead to the fundamental insight that replacement decisions are driven by marginal costs, and not by economies of scale as suggested in the literature. Finally, we describe how the optimal policy structure, i.e., the No‐Splitting and Worse Cluster Replacement Rules, can be used to reduce the computational effort required to obtain optimal replacement policies. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005  相似文献   

12.
赵英杰 《国防科技》2014,35(6):97-100
日本自卫队追求能力提升和活动范围扩大的努力受到其防卫产业发展的局限。防卫预算的有限直接导致防卫产业的市场规模狭小。部分核心技术自主研发的缺失限制了防卫产业独立发展的能力。融合式发展模式在成本核算、劳动生产率提升和产业发展稳定性等方面限制了防卫产业发展的潜力。  相似文献   

13.
建立正确的航母编队防空威胁模型是反航母任务规划成功的前提,在分析网络化条件下航母编队综合防空反导体系作战特点基础上,综合考虑反舰导弹性能、防空雷达网和编队防空火力威胁等因素,利用加权指数方法建立了网络化条件下航母编队综合防空网络威胁模型。仿真结果表明该模型能够体现航母网络化防空体系的真实情况,可以用于反航母任务规划。  相似文献   

14.
针对大型相控阵天线维修成本高、多部件维修时机难以确定、模型仿真计算困难等问题,提出一种引入区域量化的维修优化模型。建立天线阵列的区域量化模型,将天线阵列维修问题转化成一个由不同区域阵元组成的k/n系统维修优化问题。以使用可用度为约束条件,以单位时间维修费用最小为优化目标,建立引入区域量化的大型相控阵天线多部件视情维修决策优化模型,并通过算例仿真与分析进行了模型验证。结果表明:提出的维修优化模型真实有效,能够很好地解决分布不均匀的相控阵天线维修优化问题。  相似文献   

15.
根据特种作战力量网络空间防御作战系统的结构模型的预警、保护、检测、响应和恢复五个方面,按照指标的不同类型和特点,利用模糊综合评判法对指标进行量化、一致化和标准化处理,利用层次分析法确定各指标的权值,最后利用综合加权法建立综合效能评估模型从而实现对网络空间防御作战的效能评估。该方法适用性和实用性强,为网络空间防御作战效能的评估提供一种方法和思路。  相似文献   

16.
Models for integrated production and demand planning decisions can serve to improve a producer's ability to effectively match demand requirements with production capabilities. In contexts with price‐sensitive demands, economies of scale in production, and multiple capacity options, such integrated planning problems can quickly become complex. To address these complexities, this paper provides profit‐maximizing production planning models for determining optimal demand and internal production capacity levels under price‐sensitive deterministic demands, with subcontracting and overtime options. The models determine a producer's optimal price, production, inventory, subcontracting, overtime, and internal capacity levels, while accounting for production economies of scale and capacity costs through concave cost functions. We use polyhedral properties and dynamic programming techniques to provide polynomial‐time solution approaches for obtaining an optimal solution for this class of problems when the internal capacity level is time‐invariant. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   

17.
公寓房是我军住房保障体系的重要组成部分,其中又以小户型公寓房为主体,加强小户型公寓的设计研究对提高其保障效能具有现实意义。解读军队公寓住房建筑设计方案竞赛一等奖作品,指出小户型公寓采用一梯两户多层的形式在营造营区环境、降低建筑全寿命费用、改善室内舒适度等方面具有比较优势;应合理分配小户型公寓房面积,适当提高卫浴和厨房所占面积比例,控制客厅和卧室规模;应在门厅空间布局与卫浴空间分室设置、储藏空间多样化、布置多用途小空间、管井集中出户等方面提高设计的精细化程度。  相似文献   

18.
The Benders decomposition method has been successfully applied to a classic multistage, multiproduct distribution-system design problem with fixed and linear variable costs. In other applications, however, distribution-center variable throughput costs often show nonlinearity due to economies of scale. This article extends the standard problem formulation to a nonlinear distribution-system design problem and incorporates the generalized Benders decomposition method in an efficient solution algorithm. Approximate dual prices are generated by solving linear instead of concave subproblems. Thereafter these prices are adjusted to induce a more accurate representation of the concave cost function before they are incorporated in the Benders cuts, which are used to generate new binary solutions. The computational results are encouraging.  相似文献   

19.
ABSTRACT

The European arms industry is challenged by several adverse “headwinds.” Fragmentation leads to costly duplications and, in conjunction with stagnating budgets and sharply increasing costs, prevents firms from exploiting economies of scale and learning. This is exacerbated by size differentials vis-a-vis the leading US arms manufacturers and competition from emerging producers. As some “headwinds” are self-enforcing, far-reaching industrial and policy responses are required to improve the industry's outlook. As exports may not indefinitely compensate for low domestic demand, there is an economic imperative for further cross-border collaboration and consolidation. Despite various EU policy initiatives, progresses regarding the European Defence Equipment Market and strengthening the European Defence Technological Industrial Base have been relatively slow. It remains to be seen whether the European Defence Fund will be the proclaimed “game-changer,” raising competitiveness of the European arms industry. At the same time, the UK's withdrawal from the EU adds uncertainties.  相似文献   

20.
Block replacement and modified block replacement policies for two‐component systems with failure dependence and economic dependence are considered in this paper. Opportunistic maintenance policies are also considered. Where tractable, long‐run costs per unit time are calculated using renewal theory based arguments; otherwise simulation studies are carried out. The management implications for the adoption of the various policies are discussed. The usefulness of the results in the paper is illustrated through application to a particular two‐component system. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003  相似文献   

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