检索结果-内蒙古大学图书馆

Partner switching stabilizes cooperation in coevolutionary prisoner’s dilemma

Physical Review E 2009年第3期79卷 036101-036101页

作者： Feng Fu Te Wu Long Wang Program for Evolutionary Dynamics Harvard University Cambridge Massachusetts 02138 USA Center for Systems and Control State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University Beijing 100871 China

Previous studies suggest that cooperation prevails when individuals can switch their interaction partners quickly. However, it is still unclear how quickly individuals should switch adverse partners to maximize cooperation. To address this issue, we propose a simple model of coevolutionary prisoner’s dilemma in which individuals are allowed to either adjust their strategies or switch their defective partners. Interestingly, we find that, depending on the game parameter, there is an optimal tendency of switching adverse partnerships that maximizes the fraction of cooperators in the population. We confirm that the stabilization of cooperation by partner switching remains effective under some situations, where either normalized or accumulated payoff is used in strategy updating, and where either only cooperators or all individuals are privileged to sever disadvantageous partners. We also provide an extended pair approximation to study the coevolutionary dynamics. Our results may be helpful in understanding the role of partner switching in the stabilization of cooperation in the real world.

关键词： Stabilization

来源：评论

学校读者我要写书评

暂无评论

Emergence of social cooperation in threshold public goods games with collective risk

引用

Physical Review E 2009年第1期80卷 016101-016101页

作者： Jing Wang Feng Fu Te Wu Long Wang Center for Systems and Control State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University Beijing 100871 China Program for Evolutionary Dynamics Harvard University One Brattle Square Cambridge Massachusetts 02138 USA

In real situations, people are often faced with the option of voluntary contribution to achieve a collective goal, for example, building a dam or a fence, in order to avoid an unfavorable loss. Those who do not donate, however, can free ride on others’ sacrifices. As a result, cooperation is difficult to maintain, leading to an enduring collective-risk social dilemma. To address this issue, here we propose a simple yet effective theoretical model of threshold public goods game with collective risk and focus on the effect of risk on the emergence of social cooperation. To do this, we consider the population dynamics represented by replicator equation for two simplifying scenarios, respectively: one with fair sharers, who contribute the minimum average amount versus defectors and the other with altruists contributing more than average versus defectors. For both cases, we find that the dilemma is relieved in high-risk situations where cooperation is likely to persist and dominate defection in the population. Large initial endowment to individuals also encourages the risk-averse action, which means that, as compared to poor players (with small initial endowment), wealthy individuals (with large initial endowment) are more likely to cooperate in order to protect their private accounts. In addition, we show that small donation amount and small threshold (collective target) can encourage and sustain cooperation. Furthermore, for other parameters fixed, the impacts of group size act differently on the two scenarios because of distinct mechanisms: in the former case where the cost of cooperation depends on the group size, large size of group readily results in defection, while easily maintains cooperation in the latter case where the cost of cooperation is fixed irrespective of the group size. Our theoretical results of the replicator dynamics are in excellent agreement with the individual based simulation results.

关键词： cooperation mechanisms simulation results Dilemma Simulation results Endowments Group Size zero fare public goods Threshold Replication Origin Emergence group cooperation

来源：评论

学校读者我要写书评

暂无评论

Detection of slow malicious worms using multi-sensor data fusion

Detection of slow malicious worms using multi-sensor data fu...

引用

IEEE Symposium on Computational Intelligence in Security and Defense Applications, CISDA

作者： Frank Akujobi Ioannis Lambadaris Evangelos Kranakis Department of Systems and Computer Engineering Carleton University Ottawa ONT Canada Natural Science and Engineering Research Council NSERC Mathematics of Information Technology and Complex Systems MITACS Canada

Detection of slow worms is particularly challenging due to the stealthy nature of their propagation techniques and their ability to blend with normal traffic patterns. In this paper, we propose a distributed detection approach based on the generalized evidence processing (GEP) theory, a sensor integration and data fusion technique. With GEP theory, evidence collected by distributed detectors determine the probability associated with a detection decision under a hypothesis. The collected evidence is combined to arrive at an optimal fused detection decision by minimizing a cumulative decision risk function. Typically, malicious traffic flows of varying scanning rates can occur in the wild, and the difficulty in detecting slow scanning worms in particular can be exacerbated by interference from other traffic flows scanning at faster rates. Our proposed detection technique uses a window-based self adapting profiler to filter detected malicious traffic profiles with scanning rates greater than the low scanning rates we are interested in. Experiments on a live test-bed are used to demonstrate behavior of the technique.

关键词： Intrusion detection Computer worms Telecommunication traffic Detectors Bayesian methods Acquired immune deficiency syndrome Computational intelligence Data security Sensor fusion Interference

来源：评论

学校读者我要写书评

暂无评论

Architectural design patterns for logic control of manufacturing systems: The generalized device

Architectural design patterns for logic control of manufactu...

引用

XXII International Symposium on Information, Communication and Automation Technologies, ICAT

作者： Eugenio Faldella Andrea Paoli Andrea Tilli Matteo Sartini Daniele Guidi DEIS-Department of Electronics Computer Engineering and Systems University of Bologna Bologna Italy CASY-Center for Research on Complex Automated Systems University of Bologna Bologna Italy

In all automated manufacturing systems the design of the control system plays a key role for the achievement of the targeted performance. A valuable support is provided by industrial technologies vendors in terms of computational platforms, smart I/O devices, networking infrastructures, integrated development and run-time environments. What is still lacking is a reference framework comprising a comprehensive set of highly reusable logic control components that, focusing on cross-cutting functionalities characterizing the automation domain, may help the designers in the process of modeling and structuring their applications according to the specific needs. As a first step in this direction, the paper introduces a set of new components that abstractly model the behavior of manifold field devices commonly used within automated manufacturing systems, regardless their nature, intrinsic features and specific functional purposes. These components, called generalized devices, are basic logic controllers/diagnosers, which play, in our architectural multilayer organization of the overall control logic, the fundamental role of keeping cleanly distinct higher-level control policies from low-level mechanisms dealing with actuators and sensors.

关键词： Logic devices Logic design Control systems Manufacturing systems Automatic control Computer industry Electrical equipment industry Manufacturing industries Computer networks Runtime

来源：评论

学校读者我要写书评

暂无评论

Identification of torsional vibration features in electrical powered rotating equipment

Identification of torsional vibration features in electrical...

引用

27th Conference and Exposition on Structural Dynamics 2009, IMAC XXVII

作者： Trethewey, Martin W. Lebold, Mitchell S. Department of Mechanical and Nuclear Engineering Penn State University University Park PA 16802 United States Complex Systems Monitoring and Automation Department Applied Research Laboratory Penn State University University Park PA 16802 United States

ISBN: (纸本)9781605609614

A common torsional vibration sensing method in rotating equipment is the Time Interval Measurement System (TIMS). The method utilizes the time passage of discrete intervals on a rotating element from an incremental geometric encoder (i.e., gear, optical encoder). Ideal measurement conditions consist of a constant shaft running speed, an encoder with identical segments and no transverse motion between the sensor and shaft. In practice, these ideal conditions are rarely achieved resulting in measurement errors. Torsional vibration sensing in internal combustion engines benefits the large inherent responses which produces a high signal to noise ratio and tends to minimize the effects of some measurement issues. In electrical motor applications the torsional responses tend to be smaller and the measurement issues may become more pronounced. For health monitoring applications (i.e., shaft crack growth diagnostics) it is imperative to accurately identify and track the fault sensitive torsional features. Tracking torsional mechanical shaft line dynamics can become challenging because of the lower signal to noise ratio, high harmonic content induced from the motor speed controller and processing artifacts from the Time Interval Measurement System. This work will discuss a number of potential measurement and data processing issues in the application of TIMS for health monitoring applications. The work will focus on separating the desired shaft line health features from all apparent in the torsional response. Of particular interest will be practical items related to installation and analysis on large electrical driven equipment. Examples from laboratory and field tests will be used to describe the identification and compensatory methods that have been successfully used. © 2009 Society for Experimental Mechanics Inc.

关键词： Internal combustion engines

来源：评论

学校读者我要写书评

暂无评论

Could Feedback-Based Self-Learning Help Solve Networked Prisoner's Dilemma?

Could Feedback-Based Self-Learning Help Solve Networked Pris...

引用

Joint 48th IEEE Conference on Decision and Control and 28th Chinese Control Conference

作者： Xiaojie Chen Feng Fu Long Wang State Key Laboratory for Turbulence and Complex Systems Center for Systems and ControlCollege of EngineeringPeking University Department of Zoology University of British Columbia Program for Evolutionary Dynamics Harvard University

We present a self-learning evolutionary Prisoner's Dilemma game model to study the evolution of cooperation in network-structured *** the evolutionary process,each agent updates its current strategy with a probability depending on the difference feedback between its actual score and score *** agent's score is a weighed mean of its payoff coming from its neighbors(social partners) and the payoff of its social partners obtaining from *** results show that the cooperation level in the structured populations increases with increasing the weight of partners' obtaining payoff in the *** interestingly,we find that very similar evolution of cooperation can respectively emerge in lattice,small-world and scale-free networks under the learningfeedback updating ***,we provide theoretical analysis and qualitative explanations for these numerical *** work may provide an effective way to solve the dilemma of cooperation for structured populations.

关键词： Could Feedback-Based Self-Learning Help Solve Networked Prisoner's Dilemma

来源：评论

学校读者我要写书评

暂无评论

Automatic development of normal zone in composite MgB2/CuNi wires with different diameters

引用

Journal of Physics: Conference Series 2010年第1期234卷

作者： A Jokinen K Kajikawa M Takahashi M Okada Department of Electrical and Electronic Systems Engineering Kyushu University Fukuoka 819-0395 Japan Institute of Electromagnetics Tampere University of Technology PO Box 692 33101 Tampere Finland Research Institute of Superconductor Science and Systems Kyushu University Fukuoka 819-0395 Japan This work was supported by the Industrial Technology Research Grant Program in 2008 (08B38006a) from the New Energy and Industrial Technology Development Organization (NEDO) of Japan Hitachi Research Laboratory Hitachi Ltd. Ibaraki 319-1292 Japan

One of the promising applications with superconducting technology for hydrogen utilization is a sensor with a magnesium-diboride (MgB2) superconductor to detect the position of boundary between the liquid hydrogen and the evaporated gas stored in a Dewar vessel. In our previous experiment for the level sensor, the normal zone has been automatically developed and therefore any energy input with the heater has not been required for normal operation. Although the physical mechanism for such a property of the MgB2 wire has not been clarified yet, the deliberate application might lead to the realization of a simpler superconducting level sensor without heater system. In the present study, the automatic development of normal zone with increasing a transport current is evaluated for samples consisting of three kinds of MgB2 wires with CuNi sheath and different diameters immersed in liquid helium. The influences of the repeats of current excitation and heat cycle on the normal zone development are discussed experimentally. The aim of this paper is to confirm the suitability of MgB2 wire in a heater free level sensor application. This could lead to even more optimized design of the liquid hydrogen level sensor and the removal of extra heater input.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A constructive based hybrid training algorithm for feedforward neural networks

A constructive based hybrid training algorithm for feedforwa...

引用

IEEE SSD International Multi-Conference on systems, Signals and Devices

作者： Mounir Ben Nasr Mohamed Chtourou Research Unit on Intelligent Control Design & Optimization of Complex Systems (ICOS) Department of Electrical Engineering ENIS Engineering School Sfax Tunisia

This paper presents a new learning algorithm for feedforward neural networks. This algorithm uses the vigilance parameter to generate the hidden layer neurons. This process improves the initial weight problem and the adaptive neurons of the hidden layer. The proposed approach is based on combined unsupervised and supervised learning. In this algorithm, the weights between input and hidden layers are firstly adjusted by Kohonen algorithm with fuzzy neighborhood, whereas the weights connecting hidden and output layers are adjusted using gradient descent method. Two simulation examples are provided to demonstrate the efficiency of the approach compared with a number of other methods.

关键词： Neural networks Feedforward neural networks Neurons Fuzzy neural networks Vectors Organizing Euclidean distance Supervised learning Joining processes Learning systems

来源：评论

学校读者我要写书评

暂无评论

Optimal trajectory of a mobile robot by a Genetic Design Fuzzy logic controller

Optimal trajectory of a mobile robot by a Genetic Design Fuz...

引用

International Conference on Advances in Computational Tools for engineering Applications, ACTEA

作者： Chokri Rekik Mohamed Jallouli Nabil Derbel Research unit on Intelligent Control design & Optimization of complex Systems Sfax Engineering School University of Sfax Sfax Tunisia

Obstacle avoidance and path planning are the most important problems in mobile robots. Besides, finding methods for controlling and decreasing the real robot error in path have been another target for researchers investigation. Usual methods have two separated parts, research target and path planning with obstacle avoidance. In this context, a fuzzy logic controller has been constructed in order to train an intelligent robot. Genetic algorithms are used to optimize the consequences of a Sugeno fuzzy logic optimal controller for the mobile robot navigation. This is to search a target in an environment with and without obstacles. Simulation results verify successful applications of method for real motion situations. An application have been effected in the Khepera robot demonstrating. The Khepera robot can go to the goal and avoid the obstacles successfully.

关键词： Mobile robots Fuzzy logic Optimal control Genetic algorithms Virtual reality Navigation Wheels Path planning Robot control Motion control

来源：评论

学校读者我要写书评

暂无评论

Development and research of a portable impulse X-ray photons generator for the purposes of flaw detection

Development and research of a portable impulse X-ray photons...

引用

2nd International Conference on Current Problems in Nuclear Physics and Atomic Energy, NPAE 2008

作者： Burtseva, D.V. Kovaliov, D.A. Kolomiyets, N.F. Myagkov, B.A. Shikanov, A.E. Shikanov, E.A. Experimental Plant of Impulse Equipment Ltd. Moscow Russia CJSC SPEKTR Complex Testing Systems Moscow Russia Institute for Nuclear Research National Academy of Sciences of Ukraine Kyiv Ukraine Moscow Engineering and Physical Institute State University Moscow Russia

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：