The Refinement of Choreographed Multi-Agent Systems

This article describes first steps towards the formal specification and verification of multi-agent systems, through the use of temporal belief logics. The article first describes Concurrent METATEM, a multi-agent programming language, and then develops a logic that may be used to reason about Concurrent METATEM systems. The utility of this logic for specifying and verifying Concurrent METATEM systems is demonstrated through a number of examples. The article concludes with a brief discussion on the wider implications of the work, and in particular on the use of similar logics for reasoning about multi-agent systems in general.

During requirement specification process of software development activities, many existing systems or business process requirements have been captured using natural language or specialized tools such as UML. However, the capturing of informal requirements into formalized properties has not been taken into attention by software developers due to time and budget constraints. It is critical for the informally captured requirements to be formally specified in order to perform system verification. Formal verification checks whether a system model meets the formal specifications while validation checks whether the developed system fulfills its intended purpose. Therefore, in this paper, we present our studies of formal verification of multi agent system using model checking approach. We have utilized model checking tool in order to execute the formal verification procedures based on a particular basic theory to verify certain kind of properties of requirement specifications. We show an example of how model checking tool could support the verification of Universiti Teknologi Malaysia (UTM) multi agent online application system and conclude that the propose model checking approach will benefit multi agent system.

We investigate the mapping of OWL-S process models to ISPL - the system description language for MCMAS, a symbolic model checker tailored to the verification of multi agent systems. In our approach, services are viewed as agents, and service compositions as multi agent systems. We show how various composition constructs defined in OWL-S can be encoded into ISPL by using the proposed mapping rules. We use an extended version of the BravoAir process model from the OWL-S suite of examples to illustrate the technique.

A key problem in verification of multi-agent systems by model checking concerns the fact that the state-space of the system grows exponentially with the number of agents present. This often makes practical model checking unfeasible whenever the system contains more than a few agents. In this paper we put forward a technique to establish a cutoff result, thereby showing that systems with an arbitrary number of agents can be verified by checking a single system consisting of a number of agents equal to the cutoff of the system. While this problem is undecidable in general, we here define a class of parameterised interpreted systems and a parameterised temporal-epistemic logic for which the result can be shown. We exemplify the theoretical results on a robotic example and present an implementation of the technique as an extension of MCMAS, an open-source model checker for multi-agent systems.

We analyse the verification problem for synchronous, perfect recall multi-agent systems with imperfect information against a specification language that includes strategic and epistemic operators. While the verification problem is undecidable, we show that if the agents' actions are public, then verification is 2exptime-complete. To illustrate the formal framework we consider two epistemic and strategic puzzles with imperfect information and public actions: the muddy children puzzle and the classic game of battleships.

Verification of multi-agent systems is a challenging task due to their dynamic nature, and the complex interactions between agents. An example of such a system is the RoboCup Soccer Simulator, where two teams of eleven independent agents play a game of football against each other. In the present article we attempt to verify a number of properties of RoboCup football teams, using a methodology involving testing. To accomplish such testing in an efficient manner we use the McErlang model checker, as it affords precise control of the scheduling of the agents, and provides convenient access to the internal states and actions of the agents of the football teams.

The formalisation of rational agents is a topic of continuing interest in Artificial Intelligence. Research on this subject has held the limelight ever since the pioneering work of Moore [1980; 1984] in which knowledge and actions are considered. Over the years important contributions have been made on both informational aspects like knowledge and belief [Halpern and Moses, 1992; Meyer and van der Hoek, 1995], and motivational 1 aspects like commitments and obligations [Cohen, 1990]. Recent developments include the work on agent-oriented programming [Shoham, 1993; Thomas, 1993], the Belief-Desire-Intention architecture [Rao and Georgeff, 1991; Rao and Georgeff, 1991a; Rao and Georgeff, 1993], logics for the specification and verification of multi-agent systems [Wooldridge, 1994; Wooldridge and Fisher, 1992], logics for agents with bounded rationality [Huang, 1994; Huang et al., 1992], and cognitive robotics [Lesperance et al., 1994; Levesque, 1994].KeywordsRational AgentBelief RevisionKripke ModelDynamic LogicPropositional FormulaThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

The paper presents the design and implementation of ARC-a tool for automated verification of concurrent systems. The tool is based on the untimed CSP language, its semantic models and theory of refinement. We alleviate the combinatorial explosion problem using ordered binary decision diagrams (OBDDs) for the internal representation of complex data structures-sets and labeled transition systems (LTS). The semantically complex external choice operator is translated into the corresponding LTS using an optimized algorithm. This and some other implementation improvements allow verifying systems with up to 10/sup 33/ states, which is consistent with the capabilities of other OBDD based approaches. Compared to two existing CSP tools, FDR and MRC, ARC has fewer language restrictions and is more memory efficient. A performance comparison based on the n-schedulers and dining philosophers problems suggests that the checking algorithm of ARC is, in most cases, faster than those of the other tools.

The issue of creating an information security system is very relevant in the world today. One of the urgent tasks is to solve the issues of effective protection of information from both external and internal threats through the creation and implementation of information security management systems in automated systems of enterprises, which, among other things, requires the formalization of the task of protecting information for its subsequent implementation by software and other means. Now there are security analysis systems, for example, that examine the security elements settings of workstations and servers operating systems, analyze the network topology, look for unprotected network connections, examine the settings of firewalls. The disadvantage of these systems is that they are not suitable for monitoring large volumes of network traffic. The solution to this problem is the use of monitoring tools capable of analyzing large amounts of data in real time. Therefore, a significant place in the article is given to the review of developments based on artificial intelligence technologies, namely multi-agent systems, review of information security models, threat risk assessment in automated systems. The functional architecture of the information security management system based on a multi-agent system has been proposed to search in real time for information security optimal solutions through the selection of such coalitions of protection mechanisms agents that will allow to build the optimal protection of the automated system according to the selected criteria. The model with complete overlapping of threats has been substantiated and adopted as a basis, which allows to analyze the overall situation and choose strategically important decisions directly during the organization of information security. The essence of of multi-agent systems functioning that implement a decentralized control system based on the work of autonomous agents that can be implemented programmatically has been revealed. The role of threat agents, resource agents, agents of protection mechanisms and their functional purpose have been defined. The problem of searching a set of protection mechanisms agents coalition for the current state of the automated system as a problem of optimal search by the criterion of protection cost, taking into account the value of information, has been generalized. Due to the modularity of the multi-agent system, the further work will be aimed at detailing its components and perfection.

The paper deals with the multiagent systems for the power system topology verification. Two of such multiagent systems are considered. The idea of topology verification utilized in each of them allows considering the topology verification of a whole power system as the set of many local verification processes. Each of the described multiagent systems performs the topology verification over a different protocol. Types of agent defined for these systems are different. For each of the considered multiagent systems, analysis and design are outlined using the Multiagent Systems Engineering. For their design models, the performance evaluation has been carried out. Then, a comparison of the investigated multiagent systems is made, paying special attention to their performance effectiveness.Keywordsmodelingmultiagent systeminteraction protocolsimulationpower system topology verificationperformance evaluation

Recently, the popular logical frameworks on strategy specification and verification in the multi-agent concurrent systems, such as alternating-time temporal logic and Strategy Logic (SL), mainly focus on the strategic abilities of one coalition. In them, the notion of strategy is just viewed as a pure syntax and/or semantics object, we cannot represent or reason about the internal structures of strategies, let alone strategic abilities under these ones. In this paper, based on linear dynamic logic, by extending SL, we propose a new strategic logic, named Dynamic Strategy Logic (DSL), which includes the existential/ universal quantification operators about regular expressions with test expressions. By introducing action atoms, we can specify both the evolution of time and structured strategies by means of regular expressions. Hence, in this logic, we can represent and reason about much more expressive strategic abilities under structured strategies of coalitions, and prove that DSL is more expressive than SL.

This work proposes a residential load management system using multiagent technology with the objective of cost and comfort management. Smart appliances in a residential unit are modelled as agents which are controlled using optimization algorithm. These agents cooperate and communicate with each other using agent communication language (ACL) to reduce electricity cost and high peaks without affecting end user comfort. In this regards, different types of agents including load agents, price agent, temperature agent, management agent and optimal stopping rule (OSR) agent are considered. To make agent behaviour intelligent and adaptive, OSR is used. Simulations are conducted to provide the overview of residential load management using multiagent system (MAS). Simulation results show the effectiveness of MAS in terms of electricity cost, user comfort and peak shaving.

A paradigm known as multi-agent systems (MAS) combines several independent agents to accomplish intricate tasks. The creation of such systems presents difficulties with control flow, specialization, and modularity. With an emphasis on Lang-Graphbased implementation, this study examines various MAS topologies, such as network-based, supervisor-led, and hierarchical models. According to the results, MAS enhances performance and modularity while requiring careful inter-agent communication strategy design. This paper provides a thorough analysis of the architecture of Multi-Agent Systems (MAS), emphasizing its fundamental ideas, constituent parts, and uses. In the advanced distributed computing paradigm known as MAS, autonomous agents work together to resolve challenging issues. In “order to shed light on the possibilities of MAS in a number of fields, including as robotics, e-commerce, transportation, and healthcare, this study examines agent definitions, system architecture, communication protocols, decision-making methods, and practical applications. Autonomous agents are integrated in Multi-Agent Systems (MAS) to address complex issues, although control flow, specialization, and modularity present difficulties. This paper examines three topologies-network-based, supervisorled, and hierarchical-detailing inter-agent communication protocols and coordination mechanisms with an emphasis on Lang-Graph-based implementations. Each architecture is demonstrated with sample code, and the findings demonstrate that, with well-thought-out communication mechanisms, MAS improves performance and modularity. Applications include e-commerce, healthcare, transportation, and robots.

Software agents for knowledge management: coordination in multi-agent supply chains and auctions

Traditional planning theory considers the general problem of division of labor on computing devices. A fairly large class of planning tasks is included in the described task of resource allocation. The only type of resources in such tasks are computing resources. The article considers the tasks of resource allocation in multi-agent systems, options for their applicability and existing methods of solving these problems. The task of allocating resources is one of the fundamental tasks: from the efficient allocation of one's own time to the distribution between different activities and the tasks of allocating resources in large information systems. The article considers different approaches to resource allocation in large information systems: resource allocation within non-stationary tasks, stationary tasks and in multi-agent systems. These approaches help to solve various applications in real time. In the case of resource allocation in multi-agent systems, their decentralization must be taken into account: agents are directly responsible for themselves and do not have complete information about the system, which changes the very essence of the task. Thus, the development of multi-agent models is possible. The multi-agent scheduling methods used in the system can be used in real-time decentralized systems compared to the previously mentioned traditional methods. Their application provides management of planning and execution of tasks, they can be used to manage groups of objects consisting of a large number of devices and able to quickly process large-scale tasks. Thus, in a short time it is possible to design and commission based on the use of multi-agent technologies for planning new-generation software and hardware systems that can interact and work in a group and applicable to a wide range of tasks in various fields.