Primary and secondary diagnosis of multi-agent plan execution

Diagnosis of plan failures is an important subject in both single- and multi-agent planning. Plan diagnosis can be used to deal with plan failures in three ways: (i) to provide information necessary for the adjustment of the current plan or for the development of a new plan, (ii) to point out which equipment and/or agents should be repaired or adjusted to avoid further violation of the plan execution, and (iii) to identify the agents responsible for plan-execution failures. We introduce two general types of plan diagnosis: primary plan diagnosis identifying the incorrect or failed execution of actions, and secondary plan diagnosis that identifies the underlying causes of the faulty actions. Furthermore, three special cases of secondary plan diagnosis are distinguished, namely agent diagnosis, equipment diagnosis and environment diagnosis.     

Agent技术在Web服务中的应用探讨

Web服务是一组采用面向服务的体系架构的基于标准的Web协议的软件构件,而Agent是一种在某个环境中自主行动以实现其设计目标的智能化软件实体.Web服务与多Agent系统(MAS,Multi-Agent System)在架构、范例和技术方法等方面具有很大的相似性.Web服务的可信性是未来计算机软件发展关键的问题,实现Web服务在分布式环境下的协同式测试具有一定的挑战性.本文在探讨Web服务与Agent技术的共性的基础上,分析并总结了Agent技术在Web服务中的应用.针对Web服务测试的开放性、协同性、动态性和不确定性等特点,结合Agent系统的自主性、反应性、适应性和社会性,本文提出了一种基于MAS的Web服务测试框架(MAST,Multi-Agent-based Service Testing),并对其关键技术进行了探讨.     

Conceptualization and implementation of a multi-agent model to simulate whale-watching tours in the St. Lawrence Estuary in Quebec, Canada

The Saguenay St. Lawrence Marine Park (SSLMP) and the adjacent Marine Protected Area (MPA) in the St. Lawrence Estuary, in Quebec, cover a territory of exceptional biodiversity including 12 species of marine mammals, nearly half of which are considered to be endangered species. Whale-watching trips and other human activities related to commercial shipping, tourism, and recreation generate very intensive traffic in the area, which pose cumulative threats to the marine wildlife. This study has been undertaken in collaboration with the Marine Park and the MPA managers to develop a multi-agent system (MAS) to investigate the interactions between the traffic and the marine mammals in the estuary. This paper describes the first prototype version of the proposed MAS model where the focus is on the whale-watching boats. It discusses the conceptual model with its principal components: the physical environment and the boat agents and whale entities, and the implementation of the model with the behavior rules of the agents. In this version of the MAS, the whale-watching boats are represented as cognitive agents while the whales are simple reactive entities. The prototype model was implemented in the agent-based modeling platform RePast. An index, the happiness factor (i.e., the ratio of whale observation time over the trip duration) was designed to measure how successful the boat agents are in achieving their goal. Simulations were run to assess different decision strategies of the boat agents and their impacts on the whales. Results show that cooperative behavior that involves a combination of innovator and imitator strategies yields a higher average happiness factor over non-cooperative, purely innovators, behavior. However, this cooperative behavior creates increased risk for the whale populations in the estuary.     

Multi-agent based traffic simulation and integrated control of freeway corridors: Part 1 simulation and control model

Freeway corridors consist of urban freeways and parallel arterials for alternative use. Ramp metering in freeways and signal control in arterials are contemporary traffic control methods that have been developed and applied in order to improve the traffic conditions of freeway corridors. However, most existing studies have focused on either optimal ramp metering in freeways or progressive signal strategies between arterial intersections. For efficient control of freeway corridors, ramp metering and signal control must be considered simultaneously, as otherwise the control strategies for freeway operation may disturb arterial traffic. On the other hand, traffic congestion and arterial bottlenecks that arise with increasing traffic volume at peak hours and ineffective signal operation may cause problems with accessibility to freeway ramps and degrade the urban freeway’s ability to act as a through-traffic process. This research dynamically estimates the traffic stream between an urban freeway and its ramps according to changes in the freeway structure, traffic passing demand, and control methods due to restricted valid information. The results are then compared with those from other methods. Finally, the integrated control in the urban freeway traffic axis is optimized based on the expected traffic stream, by using design of experiment (DOE), neural network (NN), and a simulated annealing algorithm. This paper was recommended for publication in revised form by Associate Editor Kyongsu Yi Myung-Won Suh is a professor of Mechanical Engineering. During 1986–1988, he worked in Ford motor company as researcher. During 1989–1995, he worked in technical center of KIA motors. He took a BS Degree in Mechanical Engineering from Seoul National University and an MS Degree in Mechanical Engineering from KAIST, South Korea. He obtained his Doctorate at University of Michigan, USA, in 1989. His research areas include the structure and system optimization, advanced safety vehicle and reliability analysis & optimization. Chul-Ho Bae is a PhD candidate at Sungkyunkwan University in Suwon, South Korea. He accomplished fellowship work as researcher at Mississippi State University, USA, in 2003 and 2005. He worked in Institute of Advanced Machinery and Technology (IMAT) as a Research Assistant in 2004. He was a part time Lecturer in computer aided Mechanical Engineering of Ansan College of Technology, Suwon Science College, and Osan College during 2004–2005. He took a BS Degree in Mechanical Design and an MS Degree in Mechanical Engineering from the Sungkyunkwan University. His research interests include computer aided engineering, reliability engineering, and optimization.     

Data access in distributed simulations of multi-agent systems

Distributed simulation has emerged as an important instrument for studying large-scale complex systems. Such systems inherently consist of a large number of components, which operate in a large shared state space interacting with it in highly dynamic and unpredictable ways. Optimising access to the shared state space is crucial for achieving efficient simulation executions. Data accesses may take two forms: locating data according to a set of attribute value ranges (range query) or locating a particular state variable from the given identifier (ID query and update). This paper proposes two alternative routing approaches, namely the address-based approach, which locates data according to their address information, and the range-based approach, whose operation is based on looking up attribute value range information along the paths to the destinations. The two algorithms are discussed and analysed in the context of PDES-MAS, a framework for the distributed simulation of multi-agent systems, which uses a hierarchical infrastructure to manage the shared state space. The paper introduces a generic meta-simulation framework which is used to perform a quantitative comparative analysis of the proposed algorithms under various circumstances.     

基于SOAP的软件人通信模型研究

对比了两种常用智体通信语言KQML和FIPA-ACL,确定软件人的通信语言采用FIPAACL,从而实现与分布在世界各地的多智体系统之间能够互操作,即相互通信和交流信息。同时提出了软件人通信层;欠结构和交互模型。然而,目前FIPA消息不能穿越防火墙,极大地制约了不同Agent平台之间的互操作性,因此提出使用简单对象存取协议（simple Object Access Protocol）作为新的传输协议,该协议可以穿越防火墙FIPAACL的规范,但未完整地涉及安全问题,因此同时通过扩展SOAP解决软件人通信的安全问题,从而达到可靠的安全通信。     

电力系统无功优化调度研究综述

较为全面地综述了国内外学术界对无功优化调度问题的研究状况.通过对静态和动态无功优化调度数学模型及各种优化算法的分析,总结了该项研究的五个关键问题,即寻优质量、离散变量处理、求解效率、动态优化调度及协同优化计算和控制等.提出采用多智能体(Agent)建模及其协同优化方法进行全局实时动态无功优化调度的计算和控制.最后指出了有待深入研究的问题,例如无功优化调度的控制次序和负荷模型等.     

基于Agent的计算经济学及其在电力市场理论中的应用综述

作者在方法论层面上讨论了基于Agent的计算经济学(Agent based computational Economics,ACE)在电力市场研究中的理论价值和不足,通过分析经济学方法从数学演绎到仿真归纳的演变以及它们的内在关联性,阐明了基于Agent的计算经济学在方法论层面上的独特优越性.进一步有选择地对已有文献的综述表明,基于Agent的计算经济模型能够在更深的层次上和更广的范围内去洞察电力市场化过程.最后提出了应用ACE进行电力市场理论研究时应注意的要点以供今后的理论发展参考.     

天气雷达低噪声放大器的仿真设计

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper. The two areas are brought together in establishing an interdisciplinary interface that contributes to advancing the field of system autonomy, and pushes the engineering boundaries beyond the existing techniques. The present research adopts the experimental aspects of quantum entanglement and quantum cryptography, and integrates these established quantum capabilities into distributed robotic platforms, to explore the possibility of achieving increased autonomy for the control of multi-agent robotic systems engaged in cooperative tasks. Experimental quantum capabilities are realized by producing single photons (using spontaneous parametric down-conversion process), polarization of photons, detecting vertical and horizontal polarizations, and single photon detecting/counting. Specifically, such quantum aspects are implemented on network of classical agents, i.e., classical aerial and ground robots/unmanned systems. With respect to classical systems for robotic applications, leveraging quantum technology is expected to lead to guaranteed security, very fast control and communication, and unparalleled quantum capabilities such as entanglement and quantum superposition that will enable novel applications.     

基于Multi-Agent的电力负荷管理系统设计

为进一步提高电力负荷管理系统的智能性、实时性与可扩展性,设计了基于多代理技术（Multi—Agent）的电力负荷管理系统,此系统包括主站计算机系统、数据通信网络和现场终端系统三大部分。重点阐述了基于Multi—Agent的电力负荷管理系统的交互结构和各个Agent的具体功能,为未来的电力负荷管理系统设计提供了一条新的思路。