一种基于Agent联盟的网格资源分配方法

网格资源分配是网格计算中的关键问题之一,引起网格研究者越来越多的关注。网格资源分配的过程就是任务与资源映射的过程。在分析已有的网格资源分配方法的基础上,首先提出了一种基于Agent的网格资源管理模型,主要由用户层、客户服务层、信息服务层、区域管理层和资源层组成。在此基础上对基于Agent联盟的网格资源分配方法进行了研究,最后给出了实例分析。     

基于改进QPSO的单任务Agent联盟生成

针对群智能算法求解Agent联盟生成问题过程中易出现粒子过分聚集,导致多样性降低,甚至陷入局部最优现象提出一种基于改进量子粒子群的求解策略,在粒子过分聚集时借鉴实数编码遗传算法中的柯西变异使粒子聚集程度降低,进而维持了粒子的多样性。并采用多种群并行和最优粒子移民策略加快算法收敛。实验表明,该策略可以快速高效的求解Agent联盟,在运行效率上优于同类方法。     

自适应粒子群算法求解Agent联盟

联盟生成是多Agent系统的一个关键问题,主要研究如何在多Agent系统中动态生成面向任务的最优Agent联盟.引入粒子群算法来解决这一问题,受到惯性权重c0在进化过程中所起作用的启发,引入自适应惯性权重cadp对粒子群算法进行改进,使其不再易于陷入局部极小.对比实验结果表明,该算法在解的性能和收敛速度上均优于相关算法.     

基于模糊软集合理论的Agent联盟评价

针对多Agent系统中影响联盟功效的因素存在很强的模糊性和不确定性的问题,提出采用模糊软集合理论对Agent联盟进行综合评价。首先,待评价联盟给出自己属性,每位专家根据自己的知识和经验给出评价指标集及对应的评价矩阵;然后,利用模糊软集合理论实现评价矩阵的融合,得到最终评价结果。最后通过实例说明该方法能有效、合理地处理信息的模糊性和不确定性,评价过程符合人的思维判断。     

一种求解单任务Agent联盟生成的近似算法

联盟是多Agent之间一种重要的合作方法,如何生成面向某个任务的最优联盟是一个复杂的组合优化问题。本问题的特点是：包含较少Agent的联盟要优于包含较多Agent的联盟。根据此特点提出一种近似算法,比较实验结果表明本算法快速、有效。     

基于信任和声誉的Agent组织信誉模型

Agent组织是OOP(Object Oriented Programming)向AOP(Agent Oriented Programming)转变的重要形式,一个Agent组织要良好运行应该具有较高的信誉值,但此前这方面研究较少。针对上述问题,基于信任和声誉提出一种Agent组织信誉模型AOCM(Agent Organizational Credit Model)和计算方法,内部信任和外部声誉集成为Agent组织信誉,内部信任基于Agent之间的交互,外部声誉基于Agent的观察;改进了Dong Huynh等人关于Agent信任等方面的工作。实验结果验证了该模型的计算可行性、合理性。     

单调重叠联盟下的最优联盟结构生成

针对重叠联盟的合作博弈框架（OCF games）中重叠联盟结构生成（OCSG）求解困难的问题,提出了一种基于贪心方法的有效算法。首先使用了一种带有联盟数量k约束的OCF博弈（kOCF games）模型来限制OCSG问题的规模;然后引入了一种相似度量来表示任意两个联盟结构之间的相似程度,并基于相似度量定义了单调性的性质,这意味着某一联盟结构与最优联盟结构的相似度越高,该联盟的单调性的值就越大;最后对于具有单调性质的kOCF博弈,采用了逐一插入玩家编号以逼近最优联盟结构的方法设计了联盟约束贪心（CCG）算法来求解给定的OCSG问题,并在理论上证明了CCG算法的复杂度是O（n2^k+1）。通过实验分析和验证了不同参数和联盟值分布对所提算法性能的影响,并把该算法与Zick等提出的算法（ZICK Y,CHALKIADAKIS G,ELKIND E,et al. Cooperative games with overlapping coalitions： charting the tractability frontier. Artificial Intelligence,2019,271：74-97）在约束条件等方面进行了对比,得出了当联盟最大数量k被常数约束时所提算法的搜索次数随agent的个数基本呈线性增长的结果。可见CCG算法是固定参数k可解的,而且拥有更好的适用性。     

Multi-robot coalition formation

As the community strives towards autonomous multi-robot systems, there is a need for these systems to autonomously form coalitions to complete assigned missions. Numerous coalition formation algorithms have been proposed in the software agent literature. Algorithms exist that form agent coalitions in both super additive and non-super additive environments. The algorithmic techniques vary from negotiation-based protocols in multi-agent system (MAS) environments to those based on computation in distributed problem solving (DPS) environments. Coalition formation behaviors have also been discussed in relation to game theory. Despite the plethora of MAS coalition formation literature, to the best of our knowledge none of the proposed algorithms have been demonstrated with an actual multi-robot system. There exists a discrepancy between the multi-agent algorithms and their applicability to the multi-robot domain. This paper aims to bridge that discrepancy by unearthing the issues that arise while attempting to tailor these algorithms to the multi-robot domain. A well-known multi-agent coalition formation algorithm has been studied in order to identify the necessary modifications to facilitate its application to the multi-robot domain. This paper reports multi-robot coalition formation results based upon simulation and actual robot experiments. A multi-agent coalition formation algorithm has been demonstrated on an actual robot system.     

Organisation as development coalition

The article provides a context for the discussion of development coalitions as a key feature of modern political and economic life. It traces the history of research programmes in work organisation over the past four decades, especially in North Western Europe, and challenges conventional views on the status of research in the social sciences.     

Extensions of coalition games

We consider a class of multilevel coalition games, with each game formed as the union of traditional cooperative and coalition games. Between-level interactions are described by a sequence of such games with different sets of reward functions.Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 107–115, January–February, 1992.     

Non-additive multi-objective robot coalition formation

Manifold increase in the complexity of robotic tasks has mandated the use of robotic teams called coalitions that collaborate to perform complex tasks. In this scenario, the problem of allocating tasks to teams of robots (also known as the coalition formation problem) assumes significance. So far, solutions to this NP-hard problem have focused on optimizing a single utility function such as resource utilization or the number of tasks completed. We have modeled the multi-robot coalition formation problem as a multi-objective optimization problem with conflicting objectives. This paper extends our recent work in multi-objective approaches to robot coalition formation, and proposes the application of the Pareto Archived Evolution Strategy (PAES) algorithm to the coalition formation problem, resulting in more efficient solutions. Simulations were carried out to demonstrate the relative diversity in the solution sets generated by PAES as compared to previously studied methods. Experiments also demonstrate the relative scalability of PAES. Finally, three different selection strategies were implemented to choose solutions from the Pareto optimal set. Impact of the selection strategies on the final coalitions formed has been shown using Player/Stage.     

A knowledge-based approach to coalition formation

Establishing coalitions among humanitarian aid organizations is a challenge. The CPlanT (Coalition Planning Tool) system uses a multi-agent knowledge-based approach to reduce complexity and communication traffic, while also protecting stakeholder privacy.     

A first-order coalition logic for BDI-agents

Coalition logic (CL) enables us to model the strategic abilities and specify what a group of agents can achieve whatever the other agents do. However, some rational mental attitudes of the agents are beyond the scope of CL such as the prestigious beliefs, desires and intentions (BDI) which is an interesting and useful epistemic notion and has spawned substantial amount of studies in multi-agent systems. In this paper, we introduce a first-order coalition BDI (FCBDI) logic for multi-agent systems, which provides a semantic glue that allows the formal embedding and interaction of BDI, coalition and temporal operators in a first-order language. We further introduce a semantic model based on the interpreted system model and present an axiomatic system that is proved sound and complete with respect to the semantics. Finally, it is shown that the computational complexity of its model checking in finite structures is PSPACE-complete.     

Multi-robot coalition formation in real-time scenarios

Task allocation is one of the main issues to be addressed in multi-robot systems, especially when the robots form coalitions and the tasks have to be fulfilled before a deadline. In general, it is difficult to foresee the time required by a coalition to finish a task because it depends, among other factors, on the physical interference. Interference is a phenomenon produced when two or more robots want to access the same point simultaneously. This paper presents a new model to predict the time to execute a task. Thanks to this model, the robots needed to carry out a task before a deadline can be determined. Within this framework, the robots learn the interference and therefore, the coalition’s utility, from their past experience using an on-line Support Vector Regression method (SVR). Furthermore, the SVR model is used together with a new auction method called ’Double Round auction’ (DR). It will be demonstrated that by combining the interference model and the DR process, the total utility of the system significantly increases compared to classical auction approaches. This is the first auction method that includes the physical interference effects and that can determine the coalition size during the execution time to address tasks with deadlines. Transport like tasks run on a simulator and on real robots have been used to validate the proposed solutions.     

Hedonic coalition formation for optimal deployment

This paper presents a distributed algorithmic solution, termed Coalition formation and deployment algorithm , to achieve network configurations where agents cluster into coincident groups that are distributed optimally over the environment. The motivation for this problem comes from spatial estimation tasks executed with unreliable sensors. We propose a probabilistic strategy that combines a repeated game governing the formation of coalitions with a spatial motion component governing their location. For a class of probabilistic coalition switching laws, we establish the convergence of the agents to coincident groups of a desired size in finite time and the asymptotic convergence of the overall network to the optimal deployment, both with probability 1. We also investigate the algorithm’s time and communication complexity. Specifically, we upper bound the expected completion time of executions that use the proportional-to-number-of-unmatched-agents coalition switching law under arbitrary and complete communication topologies. We also upper bound the number of messages required per timestep to execute our strategy. The proposed algorithm is robust to agent addition and subtraction. From a coalitional game perspective, the algorithm is novel in that the players’ information is limited to the neighboring clusters. From a motion coordination perspective, the algorithm is novel because it brings together the basic tasks of rendezvous (individual agents into clusters) and deployment (clusters in the environment). Simulations illustrate the correctness, robustness, and complexity results.     

约束条件下联盟生成研究进展

联盟生成是在多Agent系统的研究中最为重要的挑战之一。如何对Agent进行划分使所得社会福利最大化是当前面临的主要问题。假设每个Agent都具有理性和自利性的特性，为了追求自身的利益最大化而选择和其他的Agent进行联合，进而使整个系统实现利益的最大化。目前，联盟生成问题有很大的计算挑战，即使在进行联盟的时候添加了约束条件，也需要新的算法来更快更有效地解决该问题。本文主要对约束条件下的联盟生成的研究进行综述，主要包括4部分:最坏情况有限界联盟生成、动态规划联盟生成求精确最优解、联盟生成求近似最优解和约束条件下联盟生成求最优解。     

Dynamic coalition formation among rational agents

Dynamic coalition formation (DCF) promises to be well suited for applications of ubiquitous and mobile computing. This article proposes a simulation-based DCF scheme designed to let rational agents form coalitions in dynamic environments.