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101.
Large initial investment in advanced manufacturing systems (AMS) makes it imperative to develop economic justification methods. Once the new system has been properly justified, a critical issue facing the firm is the optimal timing of the installation in an industry. In this paper we use a game-theoretic model by which the optimal timing of the investments in AMSs is analysed. The existence of timing equilibria is demonstrated and simple decision rules of optimal strategy are provided. Economic interpretations of the decision rules are subsequently made clear. Finally, illustrative examples are used to demonstrate the correctness and usefulness of the analysis.  相似文献   
102.
为增强安全关键系统的高可信能力,在分析高可信保障机制现状的基础上,提出了一种多层次的高可信软件架构。该架构采用时空分离思想、虚拟机技术,为基于MLS的嵌入式安全关键系统提供了一种整体解决方案。基于该架构,研究了多层次的安全和防危策略管理方法、信息流控制机制、可信软件的评估和认证方法,为安全关键嵌入式系统提供可认证的安全服务。  相似文献   
103.
Fire Risks in Oil Refineries: Economic Analysis of Camera Monitoring   总被引:1,自引:0,他引:1  
A probabilistic method is presented to evaluate the economic value of fire monitoring by closed circuit TV camera in petroleum refineries. The proposed model is restricted to the analysis of risk reduction in an area where fires can be caused either by pump failure or by failure of valves and lines. The benefits come from reducing the time during which the fire grows undetected. Fire growth and expected values of losses are analyzed by a Markov model that includes five phases: (1) active undetected growth, (2) detection, (3) fire growth at the beginning of the firemen's intervention, (4) fire control, and (5) fire extinction. The results (e.g., the expected net present value of the investment) show that the proposed monitoring investment is attractive for an illustrative example.  相似文献   
104.
智能体建模和资本市场复杂性   总被引:3,自引:0,他引:3       下载免费PDF全文
以复杂适应系统的思想和智能体建模的方法研究资本市场复杂性是新兴的有价值的研究领域,阐述了资本市场作为复杂适应系统的动力机制,介绍了这一领域一个重要模型———少数派博弈(minority game,MG)模型.仿真发现,处于拥挤阶段的MG具有和实际市场相近的收益率分布.进一步扩展标准MG,提出了快速适应的少数派博弈模型,仿真结果显示,新的模型有着和真实市场相同的特征:收益率分布的尖峰和肥尾现象,揭示了资本市场复杂性的内部动力学机理.  相似文献   
105.
李登辉提出“两国论”,为祖国统一设置障碍,祖国统一是不可阻挡的历史趋势。邓小平的“一国两制”构想是实现祖国统一大业的伟大创举。“一国两制”是实事求是的产物,“一国两制”的内涵、“一国两制”的理论和实践,是对马克思主义国家学说的新发展。  相似文献   
106.
Recently, efforts to model and assess a system's resilience to disruptions due to environmental and adversarial threats have increased substantially. Researchers have investigated resilience in many disciplines, including sociology, psychology, computer networks, and engineering systems, to name a few. When assessing engineering system resilience, the resilience assessment typically considers a single performance measure, a disruption, a loss of performance, the time required to recover, or a combination of these elements. We define and use a resilient engineered system definition that separates system resilience into platform and mission resilience. Most complex systems have multiple performance measures; this research proposes using multiple objective decision analysis to assess system resilience for systems with multiple performance measures using two distinct methods. The first method quantifies platform resilience and includes resilience and other “ilities” directly in the value hierarchy, while the second method quantifies mission resilience and uses the “ilities” in the calculation of the expected mission performance for every performance measure in the value hierarchy. We illustrate the mission resilience method using a transportation systems‐of‐systems network with varying levels of resilience due to the level of connectivity and autonomy of the vehicles and platform resilience by using a notional military example. Our analysis found that it is necessary to quantify performance in context with specific mission(s) and scenario(s) under specific threat(s) and then use modeling and simulation to help determine the resilience of a system for a given set of conditions. The example demonstrates how incorporating system mission resilience can improve performance for some performance measures while negatively affecting others.  相似文献   
107.
本文介绍了人机工程学(工效学)这一新兴边缘学科的研究内容、发展及现状,讨论了人-机系统的可靠性并着重讨论了人的操作可靠性,探讨了按人为差错进行可靠性分析与可靠性估计的人为差错和可靠性分析逻辑推演法(HERALD法)及系统能力方法(SC方法)。 本文的结论可供系统管理工作者及设计工作者,特别是可靠性管理及可靠性设计工作者参考。  相似文献   
108.
文章从分析高校科技成果产业化的制约因素入手,提出了"三张皮"体制的概念,探讨了其与市场经济之间的天然不谐调性,以及对科技成果产业化发展的影响,从而提出破解之策.  相似文献   
109.
This article looks at the ability of a relatively new technique, hybrid artificial neural networks (ANNs), to predict Japanese banking and firm failures. These models are compared with traditional statistical techniques and conventional ANN models. The results suggest that hybrid neural networks outperform all other models in predicting failure for one year prior to the event. This suggests that for researchers, policymakers, and others interested in early warning systems, the hybrid network may be a useful tool for predicting banking and firm failures.  相似文献   
110.
二元经济结构理论对解决我国三农问题的启示   总被引:1,自引:0,他引:1  
西方发展经济学的二元经济结构理论认为:只有当农业部门的剩余劳动已全部由工业部门吸收之后,农业部门的工资水平才能提高。我国当前“三农”问题产生的最主要原因:是建国初期城乡二元经济结构的制度化产生的阻滞作用。借鉴西方该理论对解决我国当前“三农”问题是一重要启示。  相似文献   
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