José Cardoso

ISEM: a multiagent Simulator for testing agent market strategies

With the increasing importance of e-commerce across the Internet, the need for software agents to support customers and suppliers in buying and selling goods/services is growing rapidly. It is becoming increasingly evident that in a few years the Internet will host a large number of interacting software agents. Most of them will be economically motivated, and will negotiate a variety of goods and services. It is therefore important to consider the economic incentives and behaviors of economic software agents, and to use all available means to anticipate their collective interactions. This paper addresses this concern by presenting a multiagent market simulator designed for analyzing agent market strategies based on a complete understanding of buyer and seller behaviors, preference models and pricing algorithms, and considering risk preferences. The system includes agents that are capable of improving their performance with their own experience, by adapting to the market conditions. The results of the negotiations between agents are analyzed by data mining algorithms to extract rules that give agents feedback to improve their strategies

E-Business Interoperability Through Ontology Semantic Mapping

With the advent of Semantic Web, knowledge-based interoperability in VE faces a new technological shift, in which ontologies and semantic web technologies plays a major role. Exploiting the explicit semantic description of the domain of discourse allows reasoning and automatically acquiring semantic relations between two different domains of discourses. Such semantic relations would be further applied in converting data between such domains. This process is named Ontology Mapping. The MAFRA—Mapping FRAmework cover all the phases of the process, including analysis, specification, representation, execution and evolution. The execution strategy and methodology are the focus of this paper. The MAFRA Toolkit is being applied in the European project Harmonise, which aims to provide solutions for (semi-) automatic interoperability between major operators in e-tourism.

A Congestion Management and Transmission Price Simulator for Competitive Electricity Markets

In a liberalized electricity market, the transmission system operator (TSO) plays a crucial role in power system operation. Among many other tasks, TSO detects congestion situations and allocates the payments of electricity transmission. This paper presents a software tool for congestion management and transmission price determination in electricity markets. The congestion management is based on a reformulated optimal power flow (OPF), whose main goal is to obtain a feasible solution for the re-dispatch minimizing the changes in the dispatch proposed by the market operator. The transmission price computation considers the physical impact caused by the market agents in the transmission network. The final tariff includes existing system costs and also costs due to the initial congestion situation and losses costs. The paper includes a case study for the IEEE 30 bus power system.

Transmission price simulator in a liberalized electricity market

This paper presents a software tool (SIMCMTP) that solves congestion situations and evaluates the taxes to be paid to the transmission system by market agents. SIMCMTP provides users with a set of alternative methods for cost allocation and enables the definition of specific rules, according to each market and/or situation needs. With these characteristics, SIMCMTP can be used as an operation aid for Transmission System Operator (TSO) or Independent System Operator (ISO). Due to its openness, it can also be used as a decision-making support tool for evaluating different options of market rules in competitive market environment, guarantying the economic sustainability of the transmission system.

A simulation-based approach for testing market strategies in electronic marketplaces

With the increasing importance of electronic commerce across the Internet it is becoming increasingly evident that in a few years the Internet will host large numbers of interacting software agents. A vast number of them will be economically motivated, and will exchange a variety of goods and services. It is therefore important to consider the economic incentives and behaviours of economic software agents, and to use every available means to anticipate their collective interactions. We address this concern by presenting a market simulator designed for analysing agent market strategies based on a complete understanding of buyer and seller behaviours, preference model and pricing algorithms.

Iterative, Incremental and Evolving EAF-Based Negotiation Process

Internally agents may use argumentation for both (i) reasoning about what to believe (i.e. theoretical reasoning) and/or (ii) for deciding what to do (i.e. practical reasoning). Despite existing differences between both, from a standpoint of first-personal reflection, a set of considerations for and against a particular conclusion are drawn on both [1]. On the other hand, concerning the types of agents’ dialogues (e.g. Deliberation, Negotiation, Persuasion, Inquiry, Information-seeking dialogues), while a clear distinction between each one exist, most of the agents’ dialogue occurrences involve mixtures of dialogue types.

Optimization model for medium term natural gas commitment

In this paper we study the optimal natural gas commitment for a known demand scenario. This study implies the best location of GSUs to supply all demands and the optimal allocation from sources to gas loads, through an appropriate transportation mode, in order to minimize total system costs. Our emphasis is on the formulation and use of a suitable optimization model, reflecting real-world operations and the constraints of natural gas systems. The mathematical model is based on a Lagrangean heuristic, using the Lagrangean relaxation, an efficient approach to solve the problem. Computational results are presented for Iberian and American natural gas systems, geographically organized in 65 and 88 load nodes, respectively. The location model results, supported by the computational application GasView, show the optimal location and allocation solution, system total costs and suggest a suitable gas transportation mode, presented in both numerical and graphic supports.