一个松散耦合的多Agent系统通信框架

传统的Agent通信采用紧耦合方式,不利于多Agent系统的扩展和异质Agent之间的互操作.分析了Web服务和语义Web服务的基本模型,借鉴了语义Web服务的体系结构思想和实现手段,在此基础上给出了一个松散耦合的多Agent通信框架.框架强调慎思式多Agent之间合作的起点是Agent对自身能力的描述和发布,通过语法封装和语义映射解决使用不同ACL(Agent通信语言)的Agent交互问题,具有灵活性、可扩展性、简单性和通用性.     

基于Web的适应性系统通信协同的研究与实现

在基于Web的适应性系统中,需要利用Agent技术来提高适应性,也需要利用常规技术来完成常规功能。要很好地进行系统各部分的协同工作,针对Agent之间以及Agent与Non-Agent之间的通信问题,阐述了Agent之间的通信模型,提出了基于Web的适应性系统的Agent部分与Non-Agent部分的通信解决方案,该方案以一个特殊的Agent管理一个服务器端口,利用一中间件向该端口写信息或从中获取信息以达到通信的目的。实验表明,这种解决方案是可行的。     

基于承诺度的寻找合作Agent的方法

在多Agent系统中,个体Agent的知识和问题求解能力是有限的,需要寻找合作Agent协作共同完成任务.本文提出承诺度概念并以简化的熟人模型为背景,将承诺度作为寻找合作Agent的依据.简化的熟人模型减少了寻找合作Agent的通信开销和资源消耗;以承诺度作为寻找合作Agent的依据减少了建立和维护熟人模型的系统开销.     

Mobile Agent系统位置透明通信的实现

在Mobile Agent系统中,Agent之间需要不断进行协作和信息交换,如何实现Agent通信的位置透明性,保证消息不会因为移动Agent的迁移而丢失,一直是移动Agent通信面临的难题,在现有的系统中都没得到很好的解决。提出了一种Mobile Agent 位置透明通信的方法,实现了通信的位置透明性、可靠性、高效性,并极大地减少了Agent迁移引起的地址注册(或更改)开销。     

多Agent系统中消息通信模型的研究与设计

在多Agent系统当中,Agent之间可以通过消息通信的方式来相互协作共同完成一个目标任务.通过对多Agent系统中消息通信机制的探索和研究,在此给出了Agent域的概念,并在Agent域的基础之上,设计了不同的消息通信模型.     

一种入侵检测系统的分布式多Agent通信机制

在基于Agent的分布式入侵检测系统中,多Agent之间的通信是一个关键的问题。文章给出了入侵检测系统的分布式多Agent通信机制,即基于双向指针的移动多Agent通信方法,实现了多Agent之间尤其是移动多Agent之间可靠通信,克服了集中式通信机制的通信瓶颈问题,还具有较好的容错性和扩展性。     

一种基于模板分析的Agent信息交换方法

提出一种基于模板分析方法,说明Agent之间通信如何使用这种方法去构造和分解消息,并说明这种方法减少了在ACL上的假设和消息格式的使用.模板的应用降低了Agent之间相互操作的需求,允许Agent在一个开放的多Agent系统中通信,可以事先不考虑缺少ACL协议和消息格式要求.     

多Agent系统的合作与通信的实现

随着信息技术的广泛发展,我们发现由于单一Agent其行为和目标具有相对的独立性,因此难以胜任复杂的任务。而多Agent系统追求的是一种集体智能、集体行为和集体目标,因而具有更广泛的适用性,多个Agent之间要进行交互和协商,要传递数据和信息,就要进行合作和通信。该文在介绍了多Agent系统的概念及特征的基础上进一步介绍了多Agent系统的组织结构和合作方式,以及多Agent通信方面的问题。     

基于多Agent系统的塔群防碰撞控制系统研究

将多Agent系统(MAS)理论应用到塔群防碰撞监控系统中.首先建立了分布式多Agent的塔群防碰撞控制模型,在此基础上,讨论了单个塔机Agent的功能结构以及多Agent系统之间的通信.针对无线通信半双工的工作特点,采用广播方式的通信机制,通过Agent在交互过程中角色的变换实现了通信网络故障监视以及网络重组,解决了实际工况下塔机工作的随机性问题,达到系统通信的全局控制.最后通过工程实践验证了通信机制的可靠性及系统的有效性.     

基于XML的Agent通信语言

Agent之间的交互与合作是Agent系统中核心问题之一，而Agent通信语言(ACL)是实现交互与合作的基础。根据目前Agent的应用环境，分析了目前主流通信语言KQML与FIPA ACL以及与之相关的内客语言的缺点，结合WWW的主流技术XML，提出基于XML的ACL。     

机会中继协同通信系统在Nakagami-m衰落信道中的折中性能分析及系统优化

针对外部窃听者对多中继协同通信系统中信息传输带来的安全威胁,提出一种由中继节点在转发信息的同时发送人工干扰信号的协同安全传输方案,并对该方案在Nakagami-m衰落信道中的安全性能进行了分析,推导出了用于评估机会中继系统可靠性的中断概率和安全性截获概率的闭式表达式,并在此基础上从可靠性和安全性两方面对系统的折中性能进行了讨论。通过仿真,验证了推导的正确性,明确了中继个数对系统折中性能的影响。最后,为进一步提高系统折中性能,讨论了系统中人工干扰信号与通信信号间的功率分配问题,并通过仿真得到了能使系统折中性能达到最优的功率分配因子。     

Effective communication,collaboration, and coordination in eXtreme Programming: Human‐centric perspective in a small organization

Effective communication, collaboration, and coordination are important contributing factors in achieving success in agile software development projects. The significance of the workplace environment and tools are immense in effective communication, collaboration, and coordination among people performing software development. In this article, we study how the workplace environment and the effective use of tools like whiteboards, status boards, and so forth for exchanging information improved communication, collaboration, and coordination without compromising the ability to do individual work by developers in a small‐scale software development organization. Based on experience and an extensive literature review of communication, collaboration, coordination, and the significance of these in the workplace environment, a survey questionnaire was developed to collect data and observe the effect of these in a small software development organization. Our study indicated appropriate workspace environment has a positive effect on communication, collaboration, and coordination in small organizations developing software using eXtreme Programming (XP). © 2009 Wiley Periodicals, Inc.     

Communication constraints in the average consensus problem

The interrelationship between control and communication theory is becoming of fundamental importance in many distributed control systems, such as the coordination of a team of autonomous agents. In such a problem, communication constraints impose limits on the achievable control performance. We consider as instance of coordination the consensus problem. The aim of the paper is to characterize the relationship between the amount of information exchanged by the agents and the rate of convergence to the consensus. We show that time-invariant communication networks with circulant symmetries yield slow convergence if the amount of information exchanged by the agents does not scale well with their number. On the other hand, we show that randomly time-varying communication networks allow very fast convergence rates. We also show that by adding logarithmic quantized data links to time-invariant networks with symmetries, control performance significantly improves with little growth of the required communication effort.     

Microsoft Outlook Web access: blessing or ban to security?

In deciding how to handle messaging access in a Microsoft Exchange environment, IT managers have an important and interesting tradeoff to make. On the one hand, employees have legitimate communication and e-mail requirements. On the other hand, providing access to messaging from outside the corporate intranet raises considerable security concerns. Obviously, no rule applies universally, and every company or organization must draw its own conclusions and make its own recommendations. This article's purpose is to provide the information you need to make the appropriate tradeoff. Outlook Web Access is not a public messaging service. Instead, it is a Microsoft software product that lets Exchange server users access their accounts with a standard Web browser.     

Using shared representations to improve coordination and intent inference

In groupware, users must communicate about their intentions and aintain common knowledge via communication channels that are explicitly designed into the system. Depending upon the task, generic communication tools like chat or a shared whiteboard may not be sufficient to support effective coordination. We have previously reported on a methodology that helps the designer develop task specific communication tools, called coordinating representations, for groupware systems. Coordinating representations lend structure and persistence to coordinating information. We have shown that coordinating representations are readily adopted by a user population, reduce coordination errors, and improve performance in a domain task. As we show in this article, coordinating representations present a unique opportunity to acquire user information in collaborative, user-adapted systems. Because coordinating representations support the exchange of coordinating information, they offer a window onto task and coordination-specific knowledge that is shared by users. Because they add structure to communication, the information that passes through them can be easily exploited by adaptive technology. This approach provides a simple technique for acquiring user knowledge in collaborative, user-adapted systems. We document our application of this approach to an existing groupware system. Several empirical results are provided. First, we show how information that is made available by a coordinating representation can be used to infer user intentions. We also show how this information can be used to mine free text chat for intent information, and show that this information further enhances intent inference. Empirical data shows that an automatic plan generation component, which is driven by information from a coordinating representation, reduces coordination errors and cognitive effort for its users. Finally, our methodology is summarized, and we present a framework for comparing our approach to other strategies for user knowledge acquisition in adaptive systems.     

基于Agent的多无人机协同飞行通信技术研究

从Agent的两大优良特性--自主性和协同性出发,研究了在多无人机协同飞行中,采用多Agent思想的协同飞行通信技术。根据多无人机协同飞行的特点,设计了多Agent协同飞行的通信协议,多Agent间传递的信息以及信息的分享模式,分析了MAS间信息传递过程;最后,通过实例介绍和分析了MAS协调通讯的构建形式,实现了多无人机协同目标定位中的数据通信。实际飞行实验结果证明,该通信机制能够控制多架无人机同时飞行,提高了通信效率,验证了该方法的可行性和有效性。     

Coordination in information exchange between organizationaldecision units

The information technology (IT) infrastructure of today's organization is often one of distributed networked computing, with a flexible architecture to incorporate diverse software and hardware components to meet the needs of different user groups. One problem that may be encountered in this environment is the lack of information exchange across user groups or teams because of incompatible data definitions, diversity of formats, and differences in information processing capabilities and IT resource allocation across the organization. Successful information flows involve a user group providing information attribute levels (e.g., levels of precision or detail, timeliness, etc.), data definitions, formats and presentation styles required by the recipient group(s). When information exchange occurs without a fit between the attribute required and that provided, we have the problem of “information coordination.” It is thus critical to design and implement a set of organizational mechanisms which will encourage units within an organization to share relevant information in a coordinated manner. We develop a stylized model of coordination based information exchange between two decision units, and show that structured communication regarding the units' intended information sharing choices can partly mitigate the problem of coordination. When there is uniformity in information management capability and IT resources across the organization, the positive impact of such communication is reinforced, These results imply an emerging role of MIS, where the latter functions as a coordinator of communication and understanding between interdependent derision units, and a facilitator of equity in information processing capability across the units     

Optimal flow control for utility-lifetime tradeoff in wireless sensor networks

In this paper, we study the utility-lifetime tradeoff in wireless sensor networks (WSNs) by optimal flow control. We consider the flow control in a more practical way by taking into account link congestion and energy efficiency in our network model, and formulate it as a constrained multi-objective optimization problem. Because of the variable coupling in the objective function, auxiliary variables are introduced to decouple it. We introduce the concept of inconsistent coordination price to balance the energy consumption of the sensor nodes. Based on the congestion price and inconsistent coordination prices, a distributed algorithm using gradient projection is proposed to solve the optimization problem. The convergence of the algorithm is also proved. Numerical results show the convergence of our algorithm, the tradeoff of utility and lifetime, as well as the necessity of considering link congestion in WSNs.     

Haptic interpersonal communication: improvement of actions coordination in collaborative virtual environments

This article explores the use of haptic feedback for interpersonal communication in collaborative virtual environments. After a detailed presentation of all communication mechanisms involved, we propose the investigation of a low-level communication approach through the feedthrough mechanism. This channel is used to communicate kinematic information about a partner??s gestures during closely coupled collaboration. Several communication metaphors, with complementary behaviors, were investigated to improve the coordination between two partners during an assembly task. The results clearly show the role of communication strategies for the improvement of gesture coordination and highlight the correlation between applied force and the level of efficiency.