Catálogo de publicaciones - libros

In this work we propose the introduction of multi-agent concepts for the organization of software development projects of (especially multi-agent) application design and implementation. This is expressed by the guiding metaphor (German: Leitbild) of a .

Team orientation and concurrent development are two aspects that are crucial in every large development project. Consequently, the organizational structure of the programming team has to take account for both. If the developed application is distributed, concurrent and team-oriented – e.g. a multi-agent application – one approach is to aim for a comparable (homomorphic) structure of a developed system and development team. We achieve this by reintroducing the multi-agent system: metaphor into the organizational structure of the development team.

Agent attributes such as autonomy, communication, cooperation, self-organization and the capacity for teamwork are transferred by the guiding metaphor back to team members. Concurrency and distribution of resources and processes is naturally supported by the guiding metaphor.

This guiding metaphor can be applied to any project organization. However, it is best suited for the organization of multi-agent application development, due to the similarity in structure.

Model Driven Development (MDD) provides an infrastructure that simplifies Multi-agent System (MAS) development by increasing the abstraction level. In addition to defining models, transformation process for those models is also crucial in MDD. On the other hand, MAS modeling should also take care of emerging requirements of MAS deployment on the Semantic Web environment. Hence, in this paper we propose a model transformation process for MDD of Semantic Web enabled MASs. We first define source and target models for the transformation regarding the modeling of interactions between agents and semantic web services and then grant mappings between these source and model entities to derive transformation rules and constraints. Finally we realize the whole transformation for a real MAS framework by using a well-known model transformation language named ATL.

Although the flexibility of agent interactions has many advantages when it comes to engineering a complex system, the downside is that it leads to certain unpredictability of the run-time system. Literature sketches two major directions for search for a solution: social-level characterization of agent systems and ontological approaches to inter-agent coordination. Especially the latter direction is not yet studied much by the scientific community. This paper describes our vision and the present state of the SmartResource Platform. The main distinctive features of the platform are externalization of behavior prescriptions, i.e. agents access them from organizational repositories, and utilization of the RDF-based Semantic Agent Programming Language (S-APL), instead of common Prolog-like languages.

We provide a new probability flow analysis algorithm to automatically identify subgoals in a problem space. Our flow analysis, inspired by preflow-push algorithms, measures the topological structure of the problem space to identify states that connect different subset of state space as the subgoals within linear-time complexity. Then we apply a hybrid approach known as subgoal-based SMDP (semi-Markov Decision Process) that is composed of reinforcement learning and planning based on the identified subgoals to solve the problem in a multiagent environment. The effectiveness of this new method used in a multiagent system is demonstrated and evaluated using a capture-the-flag scenario. We showed also that the cooperative coordination emerged between two agents in the scenario through distributed policy learning.

In this paper, we propose an approach for medical Image segmentation based on a FIPA compliant multi-agent system. The idea consists in merging the regions following several criteria and with a massive population of situated agents which cooperate, negotiate with the help of interaction protocols and communicate by passing asynchronous messages. The efficiency of our approach is shown through some experimental results.

The most common reason for plan repair are the violation of a plan’s temporal constraints. Air Traffic Control is an example of an area in which violations of the plan’s temporal constraints is rather a rule than an exception. In such domains there is a need for identifying the underlying causes of the constraint violations in order to improve plan repairs and to anticipate future constraint violations. This paper presents a model for identifying the causes of the temporal constraint violations.

Integration of agents and Web Services has been target of much interest and significant work in the last few years. In this paper an openly available implementation of a FIPA compliant Jade Message Transport System for Web Services is presented and evaluated. It provides a mechanism to integrate Jade agents transparently with Web Services, The proposed message representation is compliant with FIPA and modern Web Services standards and is part of FIPA’s initiative to create specifications for Web Services integration. Agent implementations do not require to be changed to interact with Web Services or to provide services using this tool. It also can be used to implement complex conversations as choreographies of Web Services.

Developing agent applications is a complex and difficult task due to a variety of reasons. One key aspect making multi-agent systems more complicated than traditional applications is that interaction behavior is based on elaborate communication forms such as negotiations instead of simple method calls. Aimed at facilitating the specification and usage of agent communication, agent research resulted e.g. in the definition and standardization of several general purpose interaction protocols such as contract-net or English auction. Nevertheless, the usage of these valuable interaction patterns currently forces developers to concentrate on the details of message passing instead of thinking in terms of the application domain. To alleviate this problem in this paper a goal-oriented approach is proposed, which hides message passing details allowing developers to concentrate on the domain aspects of protocols. The new approach is based on the BDI agent model and is implemented within the Jadex agent framework. The advantages of the goal-based interaction handling are further illustrated by an example application.

This paper is aimed to describe a general improvement over the previous work on the cooperative multiagent coordination. The focus is on highly dynamic environments where the message transfer delay is not negligible. Therefore, the agents shall not count on communicating their intentions along the time they are making the decisions, because this will directly add the communication latencies to the decision making phase. The only way for the agents to be in touch is to communicate and share their beliefs, asynchronously with the decision making procedure. Consequently, they can share similar knowledge and make coordinated decisions based on it. However, in a very dynamic environment, the shared knowledge may not remain similar due to the communication limitations and latencies. This may lead to some inconsistencies in the team coordination performance. Addressing this issue, we propose to hold another abstraction of the environment, called Virtual World Model (VWM), for each agent in addition to its primary internal world state. The primary world state is updated as soon as a new piece of information is received while the information affects the VWM through a synchronization mechanism. The proposed idea has been implemented and tested for Iran University of Science and Technology (IUST) RoboCupRescue simulation team, the 3 winner of the 2006 worldcup competitions.

The use of auctions for distributing resources in competing environments has produced a large variety of auctions types and algorithms to treat them. However, auctions have some problems when faced with some real-world applications containing renewable and perishable resources. In this paper we present a mechanism to deal with such issues by dynamically configuring some of the auction parameters taking into account the past experience. The mechanism has been used to coordinate industrial discharges and a Waste Water Treatment Plant, so that the treatment thresholds of the plant are never exceeded. We have performed some simulations to evaluate the system, and the results show that with this mechanism the coordination between the industries improves the treatment of the water.