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Lazar Zsolt 《Defense & Security Analysis》2018,34(2):161-175
The post-communist countries transition from the Warsaw Pact style of platforms and systems to Western-compatible capabilities has never been an easy task or a process without conflicts. This was no different for the Visegrád countries either, in which case the Hungarian Gripen procurement stands out. After much debate, Budapest decided to modernize its fighter fleet with the not battle tested Swedish-made Gripen fighter aircraft. This decision received several critiques due to the lack of transparency in the selection process and the initial lack of NATO-required systems. Subsequently, the fleet has had to operate in a financially demanding environment. Moreover, the air force has lost two aircrafts in accidents. Now that the jets are in the middle of their envisaged life cycle, it is more than appropriate to answer the question if the Gripens can utilize their full combat potential or will they fail the test of time? 相似文献
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歼击机是空中攻击的一种重要手段 ,国外很重视歼击机的研制和改进。研制新型多动能歼击机 ,改进已服役的第三代歼击机是主要发展方向。文章概述了为提高歼击机作战能力所采用的新技术和新的机载武器 相似文献
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This article examines measures of economic efficiency in aircraft production. In particular, a type of nonlinear frontier estimation is contrasted with more traditional methods for estimating a dynamic cost function. This cost function is grounded in economic theory, and it is consistent with knowledge of the aircraft-production process. The model includes the effects of both learning and production rate on total program costs. The usefulness of the model is demonstrated with an example that relates to the acquisition of military equipment. It is shown through various sensitivity analyses that an alternative procurement policy for an aircraft program could have resulted in increased efficiency and hence a lower total program cost to the government. 相似文献
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双机编队协同制导的火控机理 总被引:1,自引:0,他引:1
针对半主动雷达中制导的远距空空导弹在制导过程中对载机的强依赖性问题,提出了双机协同制导的概念;首次给出了双机协同制导的过程描述.分析了长、僚机制导过程中对导弹导引和目标跟踪过程中的各计算要素;提出了长机对目标预测并进行数据传递,僚机再通过预测值对目标实施机动和照射的协同制导思想. 相似文献
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威胁联网下低空突防航路规划研究 总被引:2,自引:0,他引:2
分析了威胁联网下信息交流和资源共享对飞行航路规划的影响;针对威胁联网,制定相关的威胁体相互支援表,采用遗传算法进行低空突防航路规划.通过仿真计算证明,此方法规划出的飞行航路能有效提高威胁联网下的战斗机低空突防安全性,为航路规划提供了一种新思路. 相似文献
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In military situations of sharply increasing combat activity the Marine Corps is faced with training problems in its expanding aviator corps. Additional training aircraft are required, and procurement decisions must be made. In view of the significant costs involved in procurement and operation of new high performance aircraft, it is very desirable to buy and operate an efficient mix of aircraft necessary for training the pilots to make the Marine Aircraft Wings essentially 100-percent tactically qualified. The mathematical model presented here enables computation of a least-cost mix of training aircraft which satisfies certain specified training requirements. The basic element allowing tradeoffs is the commonality of training available in the F4, RF4, A6, and EA6 types of aircraft. Both airframe oriented and mission oriented training are necessary, but the airframe oriented training can be conducted in either of the aircraft possessing the commonality. Training requirements over a five year period are considered, and the mix of training aircraft has the minimum five year procurement and operating cost. 相似文献
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飞行器低空突防威胁建模与航迹优化算法 总被引:2,自引:0,他引:2
提出了一种飞行器在给定地形和威胁分布的威胁场进行低空突防的航迹优化算法。该方法首先对地形的高程栅格数据进行了图形简化预处理,将各种威胁叠加到地形图上,构成一个包含各种威胁的特定威胁场,再对其建立合理的有向图数学建模,用Dijkstra最短路算法进行航迹优化。航迹优化的过程中考虑了飞行器的过载限制,使优化航迹能够较好地满足飞行器各项性能指标及任务规划的要求,仿真结果显示,该算法简单快速,能很好地进行地形、威胁、障碍物的回避。 相似文献
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We incorporate strategic customer waiting behavior in the classical economic order quantity (EOQ) setting. The seller determines not only the timing and quantities of the inventory replenishment, but also the selling prices over time. While similar ideas of market segmentation and intertemporal price discrimination can be carried over from the travel industries to other industries, inventory replenishment considerations common to retail outlets and supermarkets introduce additional features to the optimal pricing scheme. Specifically, our study provides concrete managerial recommendations that are against the conventional wisdom on “everyday low price” (EDLP) versus “high-low pricing” (Hi-Lo). We show that in the presence of inventory costs and strategic customers, Hi-Lo instead of EDLP is optimal when customers have homogeneous valuations. This result suggests that because of strategic customer behavior, the seller obtains a new source of flexibility—the ability to induce customers to wait—which always leads to a strictly positive increase of the seller's profit. Moreover, the optimal inventory policy may feature a dry period with zero inventory, but this period does not necessarily result in a loss of sales as customers strategically wait for the upcoming promotion. Furthermore, we derive the solution approach for the optimal policy under heterogeneous customer valuation setting. Under the optimal policy, the replenishments and price promotions are synchronized, and the seller adopts high selling prices when the inventory level is low and plans a discontinuous price discount at the replenishment point when inventory is the highest. 相似文献
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对国家成品油市场进行分析,认为目前国内成品油市场是典型的双寡头垄断有限竞争市场。通过对成品油市场主体厂商行为博弈的讨论,得出产量博弈的状况近期不会出现,价格博弈将使企业走入囚徒困境的结论。根据分析针对性地提出军油筹措战略,为相关决策提供参考。 相似文献
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A deterministic inventory model for reparable items 总被引:1,自引:0,他引:1
David A. Schrady 《海军后勤学研究》1967,14(3):391-398
A reparable inventory system has two distinct inventories within it—the inventory of items ready-for-issue and the inventory of carcasses available for repair. A reparable item is usually rebuilt upon failure, but the scrap rate in the repair process is generally positive. Consequently, new items must be procured from time to time to replace those item: which were scrapped. The ready-for-issue inventory has two input sources—procurement and repair, This paper develops a deterministic inbentory model for the reparable inventory system, and determines the optimal procurement and repair quantities. 相似文献
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There has been a dramatic increase over the past decade in the number of firms that source finished product from overseas. Although this has reduced procurement costs, it has increased supply risk; procurement lead times are longer and are often unreliable. In deciding when and how much to order, firms must consider the lead time risk and the demand risk, i.e., the accuracy of their demand forecast. To improve the accuracy of its demand forecast, a firm may update its forecast as the selling season approaches. In this article we consider both forecast updating and lead time uncertainty. We characterize the firm's optimal procurement policy, and we prove that, with multiplicative forecast revisions, the firm's optimal procurement time is independent of the demand forecast evolution but that the optimal procurement quantity is not. This leads to a number of important managerial insights into the firm's planning process. We show that the firm becomes less sensitive to lead time variability as the forecast updating process becomes more efficient. Interestingly, a forecast‐updating firm might procure earlier than a firm with no forecast updating. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009 相似文献