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181.
本文论述了提高智能工具机性能所采取的技术措施,并对其性能进行了模拟。模拟结果表明,智能工具机的平均推理速度可达500KLIPS 左右,比日本的PSI—Ⅰ约快一倍,比美国加州大学Berkeley 分校研制的PLM 约快两倍。  相似文献   
182.
本文以排队论为工具建立了紧耦合多处理机系统存贮器的排队模型。通过对存贮体忙期的分析,得出了存贮器有效频带的解析表达式,研究了在保证存贮器有效频带最大的情况下,处理机的访存请求率λ、存贮体的服务率μ和存贮体数m 三者之间的关系。  相似文献   
183.
本文首先介绍单片机控制的指挥仪航路产生系统的原理及组成,重点讨论了目标现在点坐标由数字量到指挥仪所需要的模拟信号的转换方法,最后对该系统的误差结果进行了分析。  相似文献   
184.
采用训练仿真系统进行武器装备的维修和操作训练是当今装备的发展趋势。某型制导炸弹是我军即将装备部队的精确制导武器,为了提高训练质量、节约训练经费和延长装备寿命,迫切需要研制该型弹训练仿真系统。介绍了基于PC/104总线的该型制导炸弹实时仿真系统的软硬件设计与实现。该系统具有操作简单,模拟控制信号精确,检测迅速准确,可扩展性强等特点,满足了部队训练和院校实验室教学的要求。  相似文献   
185.
We consider a distribution system consisting of a central warehouse and a group of retailers facing independent stochastic demand. The retailers replenish from the warehouse, and the warehouse from an outside supplier with ample supply. Time is continuous. Most previous studies on inventory control policies for this system have considered stock‐based batch‐ordering policies. We develop a time‐based joint‐replenishment policy in this study. Let the warehouse set up a basic replenishment interval. The retailers are replenished through the warehouse in intervals that are integer multiples of the basic replenishment interval. No inventory is carried at the warehouse. We provide an exact evaluation of the long‐term average system costs under the assumption that stock can be balanced among the retailers. The structural properties of the inventory system are characterized. We show that, although it is well known that stock‐based inventory control policies dominate time‐based inventory control policies at a single facility, this dominance does not hold for distribution systems with multiple retailers and stochastic demand. This is because the latter can provide a more efficient mechanism to streamline inventory flow and pool retailer demand, even though the former may be able to use more updated stock information to optimize system performance. The findings of the study provide insights about the key factors that drive the performance of a multiechelon inventory control system. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 637–651, 2013  相似文献   
186.
Rarely has a military commitment led to such intense discussion in the Netherlands as the Task Force Uruzgan (TFU) mission in Afghanistan. In February 2010, the Netherlands' coalition government even collapsed after the two largest parties failed to agree on the withdrawal of Dutch troops from Afghanistan later this year. This article deals first of all with the difficult discussion over the Afghanistan mission of the TFU. The authors then subject three ISAF operations to close scrutiny. The authors provide some suggestions to help understand better this pivotal point in the execution of the whole operation and thus give a fuller picture of the Dutch counterinsurgency approach in Uruzgan.  相似文献   
187.
By any objective measure, defense institutions in Central and Eastern Europe have all but universally been incapable of producing viable defense plans that are based on objective costing and operational planning data. This situation exists in spite the provision of considerable Western advice and assistance, let alone reporting to and receiving assessments by NATO’s International Staff under Partnership for Peace, as well as via the integrated defense planning and reporting systems. An explanation for this systematic failure across European post-Communist defense institutions can be found in the continued slow development of an over-arching policy framework which directs and approves all activities of the armed forces, as well as the de-centralization of financial decision-making down to capability providers. The essay ends with an examination of the adverse effects of the early introduction of planning programming, budgeting system (PPBS), have had on the development of effective policy and planning capabilities within these defense institutions.  相似文献   
188.
Unlike treaties dealing with nuclear and chemical weapons, the Biological Weapons Convention still lacks formal verification measures, 31 years after entering into force. Here we propose a global export-import monitoring system of biological dual-use items as an additional measure for a web of biological arms controls that could complement traditional export controls. We suggest that such a measure may help to guide consultation or verification processes in the biological area.  相似文献   
189.
Scholarly and popular literature in the recent past has framed nonproliferation diplomacy toward both Iran and North Korea as an example of “good cop/bad cop,” a social-psychological strategy borrowed from law enforcement to describe a process for forcing a confession by subjecting a target to stressful emotional contrast. This article examines those two cases, roughly covering the period since 2003, when the most recent attempts to deal with the Iranian and North Korean proliferation threats began, in light of criteria for employment of the good cop/bad cop strategy. There is some evidence that within the framework of the six-party talks with North Korea and within the framework of the EU-3-U.S. diplomacy toward Iran, the players seeking nonproliferation have adopted good cop/bad cop roles to that end. The article concludes, however, that while there are similarities to the interrogation room technique, the complexity of the international political environment as compared to the interrogation room has prevented the states involved from successfully adopting or effectively exploiting good and bad cop roles. Substantial and exploitable differences of interest among them, and the availability of alternative “escape routes” for the target state, raise serious questions about the applicability of the good cop/bad cop strategy to these two nonproliferation cases, and even about its applicability in future nonproliferation challenges.  相似文献   
190.
为了提高无人机自主飞行、自主攻击的能力,设计一种整体式的无人机综合火力/飞行控制系统(IFFC系统),并对激光制导炸弹模态下的系统进行数字仿真.系统基于Winsock的TCP/IP协议的C/S模式,在服务器上完成无人机火控解算、火飞耦合器设计,在客户端设计基于PID算法的飞行控制模块.火控系统根据飞行状态和目标信息实时计算炸弹可达区域,瞄准距离误差经过火飞耦合器形成航向和俯仰控制命令反馈给飞控系统,驱动载机消.除瞄准误差,实现闭环控制.实验结果表明,无人机的瞄准速度和攻击精度都有所提高,为进一步开展自主式UAV的研究打下基础.  相似文献   
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