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231.
集中控制混合网络中,异构化网络内部的流量具有一定的规律和特性,如果使用原有的单一的离散式最大极值和无状态的网络资源调度算法,忽略了异构网络规律,会造成网络利用率较低、易震荡、部分网络流延迟等问题。通过分析由集中控制网络和普通网络组成的混合网络的拓扑结构,对混合网络结构中常见问题如流闪现、不能估计的流、路径堵塞或连接震荡场景进行分析,并提出基于期望和状态的流量评价资源规划算法POS和POS-FME。算法考虑混合网络的运行状态,对系统可用资源进行评估,为系统中各种流匹配对应可用资源,并具有一定的预测作用,从而避免混合网络出现运行效率低下的场景。通过实验,POS算法和POS-FME算法相对传统算法,利用率提高了10%~30%,并降低了震荡和平均延迟。  相似文献   
232.
Russia has long been pursuing an intended and calculated policy of keeping enough influence in Bulgaria in order to have control over national decisions. Together with the economic, energy, political and information tools used by Russia in its hybrid war against Bulgaria and in its bid to achieve an enduring “state capture,” defence is also a distinct target of Russian subversion now. A list of noticeable subversive actions with tangible effects can be summarised, ranging from fuelling division and manipulating public opinion, preventing the strengthening of the NATO position in the Black Sea, sabotaging defence reform to various options of subverting the modernisation of the Bulgarian Armed Forces and seeking new ways to keep legacy Soviet military equipment in operation as long as possible. This issue must be urgently addressed both nationally and in NATO.  相似文献   
233.
The malaise that the United States, and the West, have experienced in recent campaigns stems in large part from unclear thinking about war, its political essence, and the strategies needed to join the two. Instead, analysis and response are predicated on entrenched theoretical concepts with limited practical utility. The inadequacy of understanding has spawned new, and not so new, terms to capture unanticipated trends, starting with the re-discovery of “insurgency” and “counterinsurgency” and leading to discussion of “hybrid threats” and “gray-zone” operations. New terminology can help, but the change must go deeper. Challenging analytical orthodoxy, this article sets out a unifying approach for the study of political violence, or more accurately: violent politics. It provides a conceptual foundation that helps to make sense of recent shifts in warfare. In effect, it offers sorely needed theoretical insights into the nature of strategy and guides the process of responding to nontraditional threats.  相似文献   
234.
朱星平 《国防科技》2021,42(1):94-99
冷战结束后,"混合战争"的威胁日益增加,人民防空工程和其他各类城市安全设施都亟需改进安全防护手段,增设安全检查设施,防控敌对势力的恐怖袭击和后方破坏.人防工程在战时对于出入口通行效率的要求远比地铁设施高,且出入口区域空间有限,无法照搬现有的地铁安检措施.本文从防范标准、安检流程以及技术手段等方面进行分析,提出运用新的检...  相似文献   
235.
通过对无人战斗机低空进入敌防区面临的各种威胁进行分析,建立了适用于圆切线算法的威胁场模型;由于可行方向法对威胁圆叠加时规划出的航路效果不理想,提出了圆的切线算法理论作为此航路规划方法的改进,采用随机产生威胁场的方法来模拟多变的战场环境,并且进行了理论分析,最后得出仿真结果.仿真证明,将两种方法结合规划出的飞行航线在航程上是比较理想的,而且路径规则的效果也得到了很大的提高.  相似文献   
236.
本文应用多目标决策原理和计算机技术,在分析用户需求的基础上,建立了科研任务项目的预测评价和经费分配模型,并分析了有关模型的关系和解决性质。根据这些模型和决策的特点,简要叙述了该系统的主要功能。我们相信。该系统的应用,将给管理人员提供方便,且使管理进一步科学化,让有限的经费发挥更大的作用。  相似文献   
237.
We present an algorithm for solving a specially structured nonlinear integer resource allocation problem. This problem was motivated by a capacity planning study done at a large Health Maintenance Organization in Texas. Specifically, we focus on a class of nonlinear resource allocation problems that involve the minimization of a convex function over one general convex constraint, a set of block diagonal convex constraints, and bounds on the integer variables. The continuous variable problem is also considered. The continuous problem is solved by taking advantage of the structure of the Karush‐Kuhn‐Tucker (KKT) conditions. This method for solving the continuous problem is then incorporated in a branch and bound algorithm to solve the integer problem. Various reoptimization results, multiplier bounding results, and heuristics are used to improve the efficiency of the algorithms. We show how the algorithms can be extended to obtain a globally optimal solution to the nonconvex version of the problem. We further show that the methods can be applied to problems in production planning and financial optimization. Extensive computational testing of the algorithms is reported for a variety of applications on continuous problems with up to 1,000,000 variables and integer problems with up to 1000 variables. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 770–792, 2003.  相似文献   
238.
We consider a simple two‐stage supply chain with a single retailer facing i.i.d. demand and a single manufacturer with finite production capacity. We analyze the value of information sharing between the retailer and the manufacturer over a finite time horizon. In our model, the manufacturer receives demand information from the retailer even during time periods in which the retailer does not order. To analyze the impact of information sharing, we consider the following three strategies: (1) the retailer does not share demand information with the manufacturer; (2) the retailer does share demand information with the manufacturer and the manufacturer uses the optimal policy to schedule production; (3) the retailer shares demand information with the manufacturer and the manufacturer uses a greedy policy to schedule production. These strategies allow us to study the impact of information sharing on the manufacturer as a function of the production capacity, and the frequency and timing in which demand information is shared. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2003  相似文献   
239.
In this paper we address the problem of how to decide when to terminate the testing/modification process and to release the software during the development phase. We present a Bayesian decision theoretic approach by formulating the optimal release problem as a sequential decision problem. By using a non‐Gaussian Kalman filter type model, proposed by Chen and Singpurwalla (1994), to track software reliability, we are able to obtain tractable expressions for inference and determine a one‐stage look ahead stopping rule under reasonable conditions and a class of loss functions. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003  相似文献   
240.
实践表明,对影响VB程序设计课程教学中存在的突出问题进行认真分析,充分利用网络教学平台,改革课堂教学方法、抓好上机实践环节。此举有效地激发了学生的学习兴趣,提高学生的编程能力,同时也有助于提高教学质量和效果。  相似文献   
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