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191.
为使NIU能提供把不同地域的仿真器联接到DIS中的能力 ,其主要功能之一就是坐标系统转换。本文介绍了DIS标准坐标系及其它几种相关坐标系 ,并在不同坐标系之间建立了坐标转换关系 ,讨论了不同坐标系中姿态的不同表示方法及其转换关系 ,同时在NIU中用C + +实现了所有算法。 相似文献
192.
Determination of the gunfire probability of kill against a target requires two parameters to be taken into consideration: the likelihood of hitting the target (susceptibility) and the conditional probability of kill given a hit (vulnerability). Two commonly used methods for calculating the latter probability are (1) treating each hit upon the target independently, and (2) setting an exact number of hits to obtain a target kill. Each of these methods contains an implicit assumption about the probability distribution of the number of hits‐to‐kill. Method (1) assumes that the most likely kill scenario occurs with exactly one hit, whereas (2) implies that achieving a precise number of hits always results in a kill. These methods can produce significant differences in the predicted gun effectiveness, even if the mean number of hits‐to‐kill for each distribution is the same. We therefore introduce a new modeling approach with a more general distribution for the number of hits‐to‐kill. The approach is configurable to various classes of damage mechanism and is able to match both methods (1) and (2) with a suitable choice of parameter. We use this new approach to explore the influence of various damage accumulation models on the predicted effectiveness of weapon‐target engagements. 相似文献
193.
Yee-Kuang Heng 《Contemporary Security Policy》2018,39(4):544-558
In the late 1990s and 2000s, a slew of books and journal articles proposed that a nexus between risk management and warfare was emerging. This article argues that risk management ideas continue to shape recent campaigns against Libya, Islamic State, Syria, and the war on terror from Niger, Yemen to Somalia. It uses existing literature on risk and warfare to examine four key aspects of contemporary interventions. First, the article evaluates the overall strategic context as security concerns shift from terrorism toward renewed great power competition. Second, it re-assesses the risk calculus for military action through the language and grammar of risk invoked by politicians. Third and fourth, it addresses the continuing reliance on air power and the managerial ethos of military operations as important features of war as risk management. 相似文献
194.
孙梅 《中国人民武装警察部队学院学报》2009,25(7):48-50
中国传统文化模式严重地制约着我国现代化的进程。只有通过深刻的文化启蒙,直接从普通民众安身立命的自在的文化根基入手,进行改造、批判和重建,才能实现我国传统文化的彻底转型。 相似文献
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196.
创新军事思想、开发作战概念是推进军事转型和部队建设的关键抓手。美军秉承“创新提炼—集智研讨—实验验证”的作战概念开发机制,采取聚焦联合作战概念开发,以作战能力需求为牵引,通过突破前沿技术和研发关键装备,以法规制度和标准规范为强制约束的做法对于军队转型建设具有重要启示。本文提出,应着眼于军队的使命任务,强化军队作战概念设计,创新作战概念研究方式,形成“聚焦使命任务—研讨演示概念—体系设计概念—检验优化概念—形成概念产品—指导建设实践”的作战概念开发途径,支撑作战概念创新和前瞻性探索研究,并加强体制机制和标准规范建设,通过对作战概念开发的整体设计和约束规范,提升前瞻作战概念对作战实践的创新引领作用,加速推进军队转型建设。 相似文献
197.
We study an (R, s, S) inventory control policy with stochastic demand, lost sales, zero lead‐time and a target service level to be satisfied. The system is modeled as a discrete time Markov chain for which we present a novel approach to derive exact closed‐form solutions for the limiting distribution of the on‐hand inventory level at the end of a review period, given the reorder level (s) and order‐up‐to level (S). We then establish a relationship between the limiting distributions for adjacent values of the reorder point that is used in an efficient recursive algorithm to determine the optimal parameter values of the (R, s, S) replenishment policy. The algorithm is easy to implement and entails less effort than solving the steady‐state equations for the corresponding Markov model. Point‐of‐use hospital inventory systems share the essential characteristics of the inventory system we model, and a case study using real data from such a system shows that with our approach, optimal policies with significant savings in inventory management effort are easily obtained for a large family of items. 相似文献
198.
We consider a dynamic pricing model in which the instantaneous rate of the demand arrival process is dependent on not only the current price charged by the concerned firm, but also the present state of the world. While reflecting the current economic condition, the state evolves in a Markovian fashion. This model represents the real‐life situation in which the sales season is relatively long compared to the fast pace at which the outside environment changes. We establish the value of being better informed on the state of the world. When reasonable monotonicity conditions are met, we show that better present economic conditions will lead to higher prices. Our computational study is partially calibrated with real data. It demonstrates that the benefit of heeding varying economic conditions is on par with the value of embracing randomness in the demand process. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 66:73–89,2019 相似文献
199.
遥感数据是国家的基础性和战略性资源,在经济建设、国防建设、抢险救灾、生态环境保护等方面得到了广泛的应用,发挥着越来越重要的作用,各行各业对遥感数据的需求也越来越多。因此,如何提高对地观测资源的利用率,提高服务响应速度成为迫切需要解决的问题。采用自然语言处理技术,提出了一种用户需求融合处理方法,该方法可以有效地融合归并相同或者相似的用户需求,实现一图多用,引入需求预测和需求融合技术以提高需求融合效率,从而提高对地观测资源的利用率,达到事半功倍的效果。 相似文献
200.
针对传统的基于协方差控制的传感器管理算法使用全遍历方法所造成的计算量大,以及传感器切换频繁的问题,提出了一种基于改进协方差控制的传感器管理算法。该算法在每一时刻首先判断前一时刻所用传感器组是否能够满足目标跟踪需求,以滤波协方差与期望协方差的偏差作为参考,结合量纲变换和特征值求取,为协方差偏差矩阵经过量纲变换后得到的量纲一致阵的所有特征值设定一个精度阈值,然后判断滤波协方差是否满足期望,从而决定是否维持当前选择的传感器组。在目标作匀速、匀加速、协同转弯等多种场景下进行了算法性能测试分析,仿真结果表明,该算法不仅在大部分场景下满足目标跟踪精度,而且能够提高传感器管理算法的实时性,同时降低传感器的切换频率。 相似文献