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301.
血小板在凝血中作用的动力学模型   总被引:1,自引:0,他引:1  
在生化实验的基础上提出了血小板在凝血中作用的动力学模型,通过定性分析和数值模拟,得到了血小板的激活比率、因子Ⅷ、Ⅸ对凝血酶生成有重要影响的一系列结论.  相似文献   
302.
This article investigates how strategic culture influenced the decision-making of Australia and Poland regarding the global coalition against the Islamic State. In the coalition, Australia has followed its tradition of active participation in United States-led operations, while Poland has embarked on a more cautious line, thereby breaking with its previous policy of active participation. The article examines how Australian and Polish responses to the coalition were shaped by five cultural elements: dominant threat perception, core task of the armed forces, strategic partners, experiences of participating in coalitions of the willing, and approach to the international legality of expeditionary operations. It finds that Australia and Poland differed on all five elements but that the major differences are found in dominant threat perception and core task of the armed forces.  相似文献   
303.
We analyze a general but parsimonious price competition model for an oligopoly in which each firm offers any number of products. The demand volumes are general piecewise affine functions of the full price vector, generated as the “regular” extension of a base set of affine functions. The model specifies a product assortment, along with their prices and demand volumes, in contrast to most commonly used demand models. We identify a fully best response operator which is monotonically increasing so that the market converges to a Nash equilibrium, when firms dynamically adjust their prices, as best responses to their competitors' prices, at least when starting in one of two price regions. Moreover, geometrically fast convergence to a common equilibrium can be guaranteed for an arbitrary starting point, under an additional condition for the price sensitivity matrix.  相似文献   
304.
This paper considers evolutionarily stable decisions about whether to initiate violent conflict rather than accepting a peaceful sharing outcome. Focusing on small sets of players such as countries in a geographically confined area, we use the concept of evolutionary stability in finite populations. We find that players’ evolutionarily stable preferences widen the range of peaceful resource allocations that are rejected in favor of violent conflict, compared to the Nash equilibrium outcomes. Relative advantages in fighting strength are reflected in the equilibrium set of peaceful resource allocations.  相似文献   
305.
针对某尾翼式火箭增程迫弹弹道飞行失稳的现象,建立了火箭增程迫弹的六自由度弹道模型,仿真分析了该弹丸的摆动角变化规律、全弹道静稳定度、动态稳定度,共振转速、平衡转速等,最终确定共振为该弹飞行失稳的主要原因。为避免弹丸共振的产生,研究确定了该弹的最佳转速范围,通过最大射程及密集度试验结果表明平衡转速为8r~10r时,发动机作用对弹丸飞行影响较小,密集度最好。  相似文献   
306.
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   
307.
基于复杂网络的“云作战”体系模型及仿真   总被引:2,自引:0,他引:2  
根据现代作战循环理论,用复杂网络的方法把作战体系的各种作战单元抽象为节点,将节点之间相互关系抽象为节点间的边,制定作战体系模型的构建规则,分别构建传统作战体系模型和“云作战”体系模型,提出作战体系度量指标,并进行仿真分析,对比两种作战体系作战能力和抗毁能力。  相似文献   
308.
针对一类非线性时滞系统,基于Lyapunov稳定性理论,讨论了不确定参数系统的鲁棒容错控制问题。当故障在失效的传感器以及失效的执行器发生时,且非线性不确定性满足一定的增益条件,通过基于线性矩阵不等式(LMI)方法各自给出了故障在传感器和执行器失效发生时,闭环系统渐近稳定的存在条件及相应控制器的设计方法。一个设计算例的仿真结果表明了该方法是有效的。  相似文献   
309.
In this article, we introduce staffing strategies for the Erlang‐A queuing system in call center operations with uncertain arrival, service, and abandonment rates. In doing so, we model the system rates using gamma distributions that create randomness in operating characteristics used in the optimization formulation. We divide the day into discrete time intervals where a simulation based stochastic programming method is used to determine staffing levels. More specifically, we develop a model to select the optimal number of agents required for a given time interval by minimizing an expected cost function, which consists of agent and abandonment (opportunity) costs, while considering the service quality requirements such as the delay probability. The objective function as well as the constraints in our formulation are random variables. The novelty of our approach is to introduce a solution method for the staffing of an operation where all three system rates (arrival, service, and abandonment) are random variables. We illustrate the use of the proposed model using both real and simulated call center data. In addition, we provide solution comparisons across different formulations, consider a dynamic extension, and discuss sensitivity implications of changing constraint upper bounds as well as prior hyper‐parameters. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 460–478, 2016  相似文献   
310.
本文从当今国际维和行动现状出发,分析了国际维和行动的特点,剖析了国际维和行动面临的挑战问题,最后对国际维和行动的发展提出几点思考,并系统阐述了维和行动的相关问题。  相似文献   
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