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161.
Tom Dyson 《Defence Studies》2019,19(2):107-129
The post-Cold War era has witnessed the rapid expansion of organisational learning initiatives within NATO militaries, especially formal “lessons-learned” processes. The effectiveness of national lessons-learned processes in recalibrating military activity to the demands of ongoing operations has been highly-differentiated. However, the academic literature on military change and practitioner guidance has been slow to investigate the key features of best-practice in military learning. This article breaks new ground by drawing upon the literature on dynamic organisational capabilities to explore the fundamental organisational processes and activities which are necessary to implement successful lessons-learned. It examines, in particular, the organisational features which facilitate “knowledge transformation”: the effective combination of new knowledge gained from intra- and inter-organisational learning with existing organisational knowledge. The article concludes by highlighting several potential future empirical and theoretical research agendas in military learning and the importance of engagement between lessons-learned practitioners and organisational learning scholars.  相似文献   
162.
面向典型任务的有人/无人机协同效能评估   总被引:1,自引:0,他引:1  
有人/无人机协同作战是C4ISR体系下的一种重要形式.本文以有人/无人机协同执行典型任务为研究背景,针对构建可靠、全面的有人/无人机协同效能理论评估方法的问题展开深入研究.首先分析了未来有人/无人机的协同模式和运用规则;然后采用协同系统综合指数模型,在单机能力模型的基础上,提出了一种有人/无人机编队协同效能评估方法;最...  相似文献   
163.
《防务技术》2020,16(3):678-688
Multilayer materials are widely used in military, automobile and aerospace industries. In this paper, the response of an explosion-welded Ti6Al4V/pure titanium with a flat interface to dynamic loading is investigated. An SHPB apparatus is used. Then, the dynamic behaviour of a bimetal sample is explored with a DIC system coupled to the SHPB. Result indicates that in the bimetal sample pure titanium is deformed and failed before Ti6Al4V. The stress curve of the sample shows two different peaks in a striker velocity higher than the 18.3 m/s. When the incident wave encounters the interface of the Ti6Al4V/pure titanium sample, only a small fraction of the wave is reflected owing to similar impedance. Using the direct interpretation stress-strain curve is unreasonable in this case because of unhomogenised plastic deformation. The microstructure of the sample is investigated after loading. An adiabatic shear band is formed in the pure titanium side before failure, and the interface of the sample remains intact under different loading conditions. The FEM simulation result for the sample is in good agreement with experimental observations.  相似文献   
164.
《防务技术》2020,16(4):856-875
Reinforced concrete (RC) columns are widely used as supporting structures for high-piled wharfs. The study of damage model of a RC column due to underwater explosion is a critical issue to assess the wharf’s antiknock security. In this study, the dynamic response and damage model of circular RC columns subjected to underwater explosions were investigated by means of scaled-down experiment models. Experiments were carried out in a 10.0 m diameter tank with the water depth of 2.25 m, under different explosive quantities (0.025 kg–1.6 kg), stand-off distances (0.0 m–7.0 m), and detonation depths (0.25 m–2.0 m). The shock wave load and dynamic response of experiment models were measured by configuring sensors of pressure, acceleration, strain, and displacement. Then, the load distribution characteristics, time history of test data, and damage models related to present conditions were obtained and discussed. Three damage models, including bending failure, bending-shear failure and punching failure, were identified. In addition, the experience model of shock wave loads on the surface of a RC column was proposed for engineering application.  相似文献   
165.
《防务技术》2020,16(6):1167-1187
The load-carrying capacities and failure patterns of reinforced concrete components can be significantly changed by membrane effects. However, limited work has been carried out to investigate the blast resistance of Hybrid Fiber Reinforced Lightweight Aggregate Concrete (HFR-LWC) members accompanying membrane action. This paper presents a theoretical approach to quantitatively depicting the membrane behavior and its contribution on the behavior of HFR-LWC beams under close-range blast loadings, and the suitability of the proposed model is validated by a series of field tests. An improved Single-Degree-of-Freedom (SDOF) model was employed to describe the dynamic responses of beam-like members under blast loadings accompanying membrane action, where the mass-load coefficient is determined according to the nonuniformly distributed load induced by close-range explosion, and the membrane action is characterized by an in-plane (longitudinal) force and a resisting moment. The elasto-plastic and recovery responses of HFR-LWC beams under the combined action of blast load and membrane force were analyzed by the promoted model. A specially built end-constrain clamp was developed to provide membrane action for the beam member when they are subjected to blast load simultaneously. It is demonstrated that the analytical displacement-time histories are in good agreement with experimental results before peak deflections and that the improved SDOF model is an acceptable tool for predicting the behavior of HFR-LWC beams under blast loadings accompanying membrane action.  相似文献   
166.
基于遗传算法的目标分配优化模型研究   总被引:2,自引:0,他引:2  
结合现代防空作战的特点,给出了现代防空作战的目标分配模型,利用遗传算法给出了模型求解的方法及步骤;实践证明该方法解题速度快,结果的精度高,可以为决策者作出科学、准确的决策提供有力支持。  相似文献   
167.
We develop a simple model to analyze the timing of contests. When the odds of winning a contest are exogenously given – we show that if either the players discount the future or if the total cost of contest is smaller in the future – there exist subgame perfect equilibria where both players settle, anticipating a contest in the future. With endogenous efforts, the aggregate efforts expanded in a contest are smaller if the contest occurs in the future when the relative effort productivities remain constant or diverge over time, thus creating scope for delay in contests. When the effort productivities converge over time, the total efforts may be greater under a future contest. As a consequence, players either settle over the two periods, or else they initiate a contest immediately.  相似文献   
168.
Defence expenditures have both costs and benefits to the economy. The costs of defence expenditures are mainly emphasized as opportunity costs. On the other hand, defence spending may have growth‐promoting potential benefits: a rise in defence spending may result in a higher aggregate demand, production and employment. This paper examines empirically the effects of military expenditures on economic growth for Middle Eastern countries and Turkey, for the time‐period 1989–1999. The relationship between military expenditure and economic growth is investigated by using cross‐section and dynamic panel estimation techniques. Empirical analysis indicates that military expenditure enhances economic growth in the Middle Eastern countries and Turkey as a whole.  相似文献   
169.
从面向对象的角度分析了弹药供应保障指挥业务流程,建立了面向对象的弹药供应保障指挥系统工作流概念模型,并以此为依据采用CPN过程建模技术进一步建立了弹药供应保障指挥系统工作流的OOCPN解析模型,为弹药补给时机和数量的控制决策提供了定量化的模型依据。由于建模方法采用了面向对象技术,因此能有效降低系统建模的复杂度,提高建模的效率,能更好地满足系统开放性、层次性和动态重组的需要,具有很高的实用价值。  相似文献   
170.
带概率因子的最小费用流经济性分析模型研究   总被引:1,自引:0,他引:1  
装备跨越式更新换代,传统的备件维修保障模式已难适应装备的发展。针对备件维修级别经济性问题,在备件及其维修网络结构分析的基础上,分析各种维修费用,并借助故障树理论,设定四类模型节点:源节点、修理决策节点、转移概率节点和结束节点;分析建立带概率因子的最小费用流经济性分析的模型网络图,结合概率因子分析各种维修费用,由此建立最小费用流的经济性分析模型,并实例论证了该模型的可行性,为解决备件维修级别问题提供了一种新的思路。  相似文献   
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