A Paradigm for Dynamic Coordination of Multiple Robots

In this paper, we present a paradigm for coordinating multiple robots in the execution of cooperative tasks. The basic idea in the paper is to assign to each robot in the team, a role that determines its actions during the cooperation. The robots dynamically assume and exchange roles in a synchronized manner in order to perform the task successfully, adapting to unexpected events in the environment. We model this mechanism using a hybrid systems framework and apply it in different cooperative tasks: cooperative manipulation and cooperative search and transportation. Simulations and real experiments demonstrating the effectiveness of the proposed paradigm are presented.     

Dynamic consistency in process algebra: From Paradigm to ACP

The coordination modelling language Paradigm addresses collaboration between components in terms of dynamic constraints. Within a Paradigm model, component dynamics are consistently specified at various levels of abstraction. The operational semantics of Paradigm is given. For a large, general subclass of Paradigm models a translation into process algebra is provided. Once expressed in process algebra, relying on a correctness result, Paradigm models are amenable to process algebraic reasoning and to verification via the mCRL2 toolset. Examples of a scheduling problem illustrate the approach.     

基于参数协调模型的多学科协同设计方法

采用传统方法解决多学科的设计问题时 ,因为无法定量考虑分布在多个学科内的产品指标对设计变量的影响 ,通常会产生频繁的设计返工 .该文通过收集产品各领域的指标约束与关系约束来构建基于约束网络的产品参数协调模型 ,采用区间描述设计变量的不确定性信息 ,并将区间算法与基因算法相结合实现了一致性模型求解框架 .使用该方法能够检测潜在冲突 ,得到与给定产品指标相对应的设计变量可行解空间 ,进而辅助设计人员决策 .最后以该方法在转向架设计中的应用实例说明其有效性 .     

基于Wave模型的QoS路由选择

MPLS和DiffServ等新的组网技术的实现，为未来的Internet骨干网引入了强大的功能，这有助于全面提供端到端的QoS。提出了一种新颖而有力的路由选择方案，使用移动代理支持QoS路由选择，特别是在满足一组业务流的QoS需求的同时，该方案使用移动代理有效地实现了基于Wave模型的多点到点的路由选择树。     

MAS构建中的主观协调和客观协调研究

文章对MAS中协调的概念进行了分析,提出了MAS中同时存在主观协调和客观协调的观点。以两个agent堆积木块为例,阐释了主观协调和客观协调的本质区别。根据主观协调和客观协调对MAS构建的影响,结合对JAFMAS平台的分析,提出可以建立主观协调模型到本地模型、客观协调模型到社会模型的映射,从而提高基于JAFMAS平台开发MAS应用的效率。     

Roles as a Coordination Construct: Introducing powerJava

In this paper we apply the role metaphor to coordination. Roles are used in sociology as a way to structure organizations and to coordinate their behavior. In our model, the features of roles are their dependence on an institution, and the powers they assign to players of roles. The institution represents an environment where the components interact with each other by using the powers attributed to them by the roles they play, even when they do not know each other. The interaction between a component playing a role and the role is performed via interfaces stating the requirements to play a role, and which powers are attributed by roles. Roles encapsulate their players' capabilities to interact with the institution and with the other roles, thus achieving separation of concerns between computation and coordination. The institution acts as a coordinator which manages the interactions among components by acting on the roles they play, thus achieving a form of exogenous coordination. As an example, we introduce the role construct in the Java programming language, providing a precompiler for it. In order to better explain the proposal, we show how to use the role construct as a coordination means by applying it to a dining philosophers problem extended with dynamic reconfiguration.     

Self Organization and Coordination

In this paper, I analyze the organization of tasks or activities by acollection of agents. I begin by formally defining organized collections androbustly organized collections of agents in the context of a simple model.Within this framework, I demonstrate that organized collections androbustly organized collections exist and equilibria need not beorganized. I then test whether adaptive agents can self-organize inthis environment. I find that simple behavioral rules can lead to nearly organized, fairly robust collections of agents.     

Efficient Group Coordination in Multicast Trees

The majority of today's Internet applications relies on point-to-point communication. In recent years, however, multipoint communication support has become the foundation for such applications as multiparty video conferencing, distributed interactive simulations, and collaborative systems. We describe a novel protocol to coordinate multipoint groupwork within the IP-multicast framework. The protocol supports Internet-wide coordination for large and highly-interactive groupwork, relying on the dissemination of coordination directives among group members across a shared end-to-end multicast tree. We also describe how addressing extensions to IP multicast can be used for our multisite coordination mechanism.     

An Efficient Bounds Consistency Algorithm for the Global Cardinality Constraint

Previous studies have demonstrated that designing special purpose constraint propagators can significantly improve the efficiency of a constraint programming approach. In this paper we present an efficient algorithm for bounds consistency propagation of the generalized cardinality constraint (gcc). Using a variety of benchmark and random problems, we show that on some problems our bounds consistency algorithm can dramatically outperform existing state-of-the-art commercial implementations of constraint propagators for the gcc. We also present a new algorithm for domain consistency propagation of the gcc which improves on the worst-case performance of the best previous algorithm for problems that occur often in applications.     

Coordination in a Content-Addressable Web

The World Wide Web is a very successful phenomenon, and is increasingly being used as a medium for electronic commerce rather than simple information exchange. In this paper it is argued that the low-level infrastructure of the Web is badly suited for these new applications, as well as being somewhat inefficient in its original applications; an alternative infrastructure offering better functionality and flexibility is proposed. The new infrastructure is based on the Linda coordination model, and adds a layer of abstraction over the absolute location of resources. Both theoretical and real-world issues are covered, including the problem of integrating this new system with the existing infrastructure of the Web.     

分布式仿真系统中的全局一致性问题研究

系统一致是分布仿真应用DSA的基础和前提。为提高DSA的全局一致性程度,获得真实、可信的仿真结果,首先阐述了DSA全局一致性问题;然后以某分布仿真系统为例,系统阐述了其全局不一致现象;在此基础上,分析了DSA系统的全局一致性需求;最后,重点给出了模型域、服务域和认知域内的一致性控制策略与建议。本研究可为DSA系统设计与开发人员提供技术与方法指导。     

Coordination in Competitive Environments

Despite several researches in autonomous agents important theoretical aspects of multi-agent coordination have been largely untreatable. Multiple cooperating situated agents support the promise of improved performance and increase the task allocation problems in cooperative environments. We present a general structure for coordinating heterogeneous situated agents that allows both autonomy of each agent as well as explicit coordination of them. Such situated agents are embodied for taking into account their situation to solve any action. Indeed, organizational features have been used as metaphor to achieve highest levels of interactions in an agent system. Then, a decision algorithm has been developed to perform a match between the situated agent knowledge and the requirements of an action. Finally, this paper presents preliminary results in a simulated robot soccer scenario showing an improvement of around 92% between the worst and the best cases.     

Voice Loops as Coordination Aids in Space Shuttle Mission Control

Voice loops, an auditory groupware technology, are essential coordination support tools for experienced practitioners in domains such as air traffic management, aircraft carrier operations and space shuttle mission control. They support synchronous communication on multiple channels among groups of people who are spatially distributed. In this paper, we suggest reasons for why the voice loop system is a successful medium for supporting coordination in space shuttle mission control based on over 130 hours of direct observation. Voice loops allow practitioners to listen in on relevant communications without disrupting their own activities or the activities of others. In addition, the voice loop system is structured around the mission control organization, and therefore directly supports the demands of the domain. By understanding how voice loops meet the particular demands of the mission control environment, insight can be gained for the design of groupware tools to support cooperative activity in other event-driven domains.     

基于语义的协同模型研究

大规模并行与分布式系统的出现开拓了软件技术的应用前景,要开发大规模并行与分布式系统的全部潜能,必须要处理系统中大量并发的活动体的协同过程。以Linda为代表的基于共享数据空间的协同模型和协同语言具有时间解耦、空间解耦和引用解耦的特点,为大规模并行与分布式系统的设计与发展提供了一种新方法。该文以多Agent系统为应用背景,研究有关Agent协同模型的问题,解决了现在大多数协同模型中缺乏语义信息的问题。     

Learning Situation-Specific Coordination in Cooperative Multi-agent Systems

Achieving effective cooperation in a multi-agent system is a difficult problem for a number of reasons such as limited and possibly out-dated views of activities of other agents and uncertainty about the outcomes of interacting non-local tasks. In this paper, we present a learning system called COLLAGE, that endows the agents with the capability to learn how to choose the most appropriate coordination strategy from a set of available coordination strategies. COLLAGE relies on meta-level information about agents' problem solving situations to guide them towards a suitable choice for a coordination strategy. We present empirical results that strongly indicate the effectiveness of the learning algorithm.     

Software Architectures and Coordination Models

Coordination models and Software Architectures are strictly related but only a little attention has been paid to their integration. What we propose in this paper is an approach to trace coordination requirements from their definition to the low level specification. The UML Unified Process is extended to gain this objective and the theory is applied to a case study.     

基于Agent的区域交通流协调控制的研究

以Agent技术为基础,对区域交通协调控制进行了研究。首先对区域交通流控制的Agent组成及结构做了简单的说明,然后对路段Agent与路口Agent的协商策略进行描述,在此基础上对一个较简单的路网进行仿真,从而证实该文所研究的基于Agent进行区域交通流协调控制的有效性。