Fabiola y López

Constraining autonomy through norms

Despite many efforts to understand why and how norms can be incorporated into agents and multi-agent systems, there are still several gaps that must be filled. This paper focuses on one of the most important processes concerned with norms, namely that of norm compliance. However, instead of taking a static view of norms in which norms are straighforwardly complied with, we adopt a more dynamic view in which an agents motivations, and therefore its autonomy, play an important role. We analyse the motivations that an agent might have to comply with norms, and then formally propose a set of strategies for use by agents in norm-based systems. Finally, through some simulation experiments, the effects of autonomous norm compliance in both individual agents and societies are analysed.

A Model of Normative Multi-agent Systems and Dynamic Relationships

For agents, one of the advantages of being part of a society is the satisfaction of those goals whose success depends on the abilities of other agents. In turn, societies are controlled by norms and, consequently, agents must be able first to model the society in which they exist, and then to identify the different relationships, due to norms, in which they might be involved in order to act appropriately. Both of these could mean the difference between the success or failure of their goals. To this end, this paper focuses on the identification of the basic components of norm-based systems, and on representing and analysing the dynamic relationships between member agents which result from the processing of norms.

An Agent-Based Model for Hierarchical Organizations

Hierarchical structures have been widely used by human organizations because they provide the natural means to delegate tasks, to reduce communication lines and to control the activities performed into them. This has motivated the development of different approaches to automate many of the activities that take place in hierarchical organizations. Recent frameworks, such as Gaia, Aalaadin , HarmonIA and OperA, among others, have considered the agent paradigm to do so without taking into account that organizations are dynamic entities that evolve with the time and, consequently, agents must adapt to changes. Here we develop a model for flexible and open hierarchical organizations where agents can dynamically adapt themselves to organizational changes.

Tiancalli06: An Agent for the Supply Chain Management Game 2006

For two years now, the Tiancalli project has been developed. This project consists in the construction of a TAC SCM compliant agent. The contest is about different software agents competing for a simulated market. This year, we present the Tiancalli06 agent. In this article the learning techniques implemented to the agent are described. These strategies are used so the agent can compete in the market and obtain incomes. The final results about the performance of the agent on the three phases that it participated are also presented - Qualification, Seeding and Quarter Finals. The previous results of this Project can be found in [8, 9, 10, 11, 12].

Statistic Analysis for the Tiancalli Agents on TAC SCM 2005 and 2006

During the last two years we have developed the Tiancalli project. This project includes the construction of TAC SCM compliant agents. The TAC SCM is a contest about different software agents competing in a simulated market that has been organized for four years by Trading Agent Research Group. In order to find the strength and weakness of our agent, we have made a statistic research with both 2005 and 2006 game results. The objective of this article is to present the results obtained in this comparison. Also it is important to discuss a more concrete basis about factors that must be modified, such as the ones which should be kept on the TAC SCM 2007

Agents Development for a Supply Chain Management Game

With the purpose of studying dynamic markets where different suppliers and customers interact, a platform which allows competition between agents in an environment of supply chains has been developed at Carnegie Mellon University. It is known as The trading agent competition: supply chain management game (TAC SCM). In this game, agents that represent computer sellers use different strategies to gain customer requests and to assure that the required components to satisfy them would be received in time. At the end of the game, the winner agent gets the highest utilities through the non-static conditions of the market. In this article, eight different agents able to compete in this game are presented and the results of their performance in different rounds are discussed

Empowered Situations of Autonomous Agents

Identifying situations in which power exists is an ability that agents can exploit when they must interact with one another. In particular, agents can take advantage of empowered situations to make other agents satisfy their goals. The aim of this paper is to identify situations in which power might exist through the roles agents play in a society as well as the powers that emerge from their own capabilities. However, unlike other models in which power is eternal and absolute, in our model power is always considered as being dynamic.

The Virtual Paragraph as a Retrieval Information Technique Implanted in Mobile Agents

Nowadays the information contained in networks increases constantly, and the way to access this information and to gather important data to the users becomes a tedious task. The purpose of this work is to show the use of mobile agents to recover valuable information for the users they represent. In this work mobile agents are endowed with different strategies to retry information. Our approach is to obtain summaries by using the transition point technique (Punto de Transition) and to select those documents and sentences that have a high similarity with the users requirements. To validate the summaries, the DUC 2002 and a statistical analysis are used. Moreover, the implementation of mobile agents is made in JADE.

Mobile Agents with ProActive for Document Extracts

Information retrieval (IR) deals with the searching of document extracts that provide the nearest approach to a users query. Due the growing of Internet there is a necessity to effectively use the information available in remote servers. Here data are distributed and, therefore, the searching mechanisms should be more efficient; otherwise, this may increase the traffic in a network. One of the benefits of mobile agents is that they reduce the communication costs between the hosts where the information is available and the central processor where the processing of information is done. That is, instead of sending messages with all the data in a local host, mobile agents are able to work in local processors and to send only the data that they consider relevant. This work shows how mobile agents can facilitate the process of information retrieval by using a platform to program distributed systems (ProActive). Different migration strategies for agents are implemented and the results are showed