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131.
前景理论(Prospect Theory,PT)描述了个体在不确定条件下的决策规律,较好地刻画了决策者的风险偏好。分析表明,PT在作战决策建模中具有一定的适用性和可行性。提出了一种基于PT的计算机生成兵力(Computer Generated Forces,CGF)Agent决策建模方法,给出了CGF Agent的建模框架,对CGF Agent决策过程中方案选择的具体步骤和算法进行了详细阐述。实验表明,所提出的方法在一定程度上提高了CGF Agent决策行为的真实性,证明了所提出方法的有效性。  相似文献   
132.
离散动态贝叶斯网络是对动态系统进行建模和定性推理的有力工具。由于观测证据会随时间增加,直接计算推理算法的公式会变得冗长而且推理速度还会下降。在直接计算推理算法的基础上推导出递推公式,并给出算例验证。递推计算公式简洁,仿真表明递推算法的推理速度较直接计算推理算法有明显提高,因而适合实时在线推理。最后将递推算法应用于航天器的态势感知。  相似文献   
133.
基于复杂网络的作战网络分析   总被引:1,自引:0,他引:1  
分布式网络化作战是网络中心战的基础,而分布式作战网络的构建是网络化作战的重要前提。首先,运用复杂网络的相关参数分析了多种不同的网络,选择了BA非标度网络作为分布式作战网络的最优表现形式;其次,以BA非标度网络为基础提出了一个适合军事上动态鲁棒性分析的模型DCNCE;最后,仿真结果表明,在以网络效能值为测度的对比下,分布式作战网络在介数毁伤策略下更脆弱,为构建并改进现有的作战网络提供了理论依据。  相似文献   
134.
In this article, we develop a novel electric power supply chain network model with fuel supply markets that captures both the economic network transactions in energy supply markets and the physical network transmission constraints in the electric power network. The theoretical derivation and analysis are done using the theory of variational inequalities. We then apply the model to a specific case, the New England electric power supply chain, consisting of six states, five fuel types, 82 power generators, with a total of 573 generating units, and 10 demand market regions. The empirical case study demonstrates that the regional electric power prices simulated by our model match the actual electricity prices in New England very well. We also compute the electric power prices and the spark spread, an important measure of the power plant profitability, under natural gas and oil price variations. The empirical examples illustrate that in New England, the market/grid‐level fuel competition has become the major factor that affects the influence of the oil price on the natural gas price. Finally, we utilize the model to quantitatively investigate how changes in the demand for electricity influence the electric power and the fuel markets from a regional perspective. The theoretical model can be applied to other regions and multiple electricity markets under deregulation to quantify the interactions in electric power/energy supply chains and their effects on flows and prices. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009  相似文献   
135.
Todas information and communication network requires a design that is secure to tampering. Traditional performance measures of reliability and throughput must be supplemented with measures of security. Recognition of an adversary who can inflict damage leads toward a game‐theoretic model. Through such a formulation, guidelines for network designs and improvements are derived. We opt for a design that is most robust to withstand both natural degradation and adversarial attacks. Extensive computational experience with such a model suggests that a Nash‐equilibrium design exists that can withstand the worst possible damage. Most important, the equilibrium is value‐free in that it is stable irrespective of the unit costs associated with reliability vs. capacity improvement and how one wishes to trade between throughput and reliability. This finding helps to pinpoint the most critical components in network design. From a policy standpoint, the model also allows the monetary value of information‐security to be imputed. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009  相似文献   
136.
爆炸逻辑间隙零门实验研究   总被引:2,自引:0,他引:2       下载免费PDF全文
为了可靠实现爆炸逻辑间隙零门的原理功能,提出并验证了一种基于精细RDX和含能胶合剂的传爆药方案.通过实验探索了基于该传爆药的爆炸零门适用的间隙宽度范围,并设计了一种小尺寸爆炸逻辑间隙零门,为爆炸逻辑网络设计提供参考.  相似文献   
137.
Many manufacturers sell their products through retailers and share the revenue with those retailers. Given this phenomenon, we build a stylized model to investigate the role of revenue sharing schemes in supply chain coordination and product variety decisions. In our model, a monopolistic manufacturer serves two segments of consumers, which are distinguished by their willingness to pay for quality. In the scenario with exogenous revenue sharing ratios, when the potential gain from serving the low segment is substantial (e.g., the low‐segment consumers' willingness to pay is high enough or the low segment takes a large enough proportion of the market), the retailer is better off abandoning the revenue sharing scheme. Moreover, when the potential gain from serving the low (high) segment is substantial enough, the manufacturer finds it profitable to offer a single product. Furthermore, when revenue sharing ratios are endogenous, we divide our analysis into two cases, depending on the methods of cooperation. When revenue sharing ratios are negotiated at the very beginning, the decentralized supply chain causes further distortion. This suggests that the central premise of revenue sharing—the coordination of supply chains—may be undermined if supply chain parties meticulously bargain over it.  相似文献   
138.
Information technology (IT) infrastructure relies on a globalized supply chain that is vulnerable to numerous risks from adversarial attacks. It is important to protect IT infrastructure from these dynamic, persistent risks by delaying adversarial exploits. In this paper, we propose max‐min interdiction models for critical infrastructure protection that prioritizes cost‐effective security mitigations to maximally delay adversarial attacks. We consider attacks originating from multiple adversaries, each of which aims to find a “critical path” through the attack surface to complete the corresponding attack as soon as possible. Decision‐makers can deploy mitigations to delay attack exploits, however, mitigation effectiveness is sometimes uncertain. We propose a stochastic model variant to address this uncertainty by incorporating random delay times. The proposed models can be reformulated as a nested max‐max problem using dualization. We propose a Lagrangian heuristic approach that decomposes the max‐max problem into a number of smaller subproblems, and updates upper and lower bounds to the original problem via subgradient optimization. We evaluate the perfect information solution value as an alternative method for updating the upper bound. Computational results demonstrate that the Lagrangian heuristic identifies near‐optimal solutions efficiently, which outperforms a general purpose mixed‐integer programming solver on medium and large instances.  相似文献   
139.
军事通信网综合管理系统中,各专业网络运行情况的主要数据都可汇总到综合网管数据库中。这些网管数据中隐含了网络运行的几乎全部信息,但即使是最有经验的网络管理专家面对这些繁杂的数据也只能望洋兴叹。面对大数据的智能分析技术则有可能实现网络运行态势的高度可视化,充分理解和详细把握全网运行状态,像知识、经验、联想丰富的专家一样不知疲倦地对网络运行状况进行全面细致地分析,从海量的网管数据中发现网络故障的蛛丝马迹,发现隐含的问题,预知网络变化。论文介绍了利用大数据分析技术实现网络管理智能化的现实目标,基于性能的网络异常预测预报、基于性能和事件的故障分析诊断、网络运行知识的挖掘利用等方面的功能和技术途径。  相似文献   
140.
In this paper, we derive new families of facet‐defining inequalities for the finite group problem and extreme inequalities for the infinite group problem using approximate lifting. The new valid inequalities for the finite group problem include two‐ and three‐slope facet‐defining inequalities as well as the first family of four‐slope facet‐defining inequalities. The new valid inequalities for the infinite group problem include families of two‐ and three‐slope extreme inequalities. These new inequalities not only illustrate the diversity of strong inequalities for the finite and infinite group problems, but also provide a large variety of new cutting planes for solving integer and mixed‐integer programming problems. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
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