Browsing by Author "Coelho, Helder"
Now showing 1 - 7 of 7
Results Per Page
Sort Options
- Agent-based simulation of retail electricity markets: Bilateral trading playersPublication . Lopes, Fernando; Algarvio, Hugo; Coelho, HelderThe electricity industry throughout the world, which has long been dominated by vertically integrated utilities, has experienced major changes. Deregulation, unbundling, wholesale and retail wheeling, and real-time pricing were abstract concepts a few years ago. Today market forces drive the price of electricity and reduce the net cost through increased competition. As power markets continue to evolve, there is a growing need for advanced modeling approaches. Accordingly, this article looks at using software agents to help manage the complexity of electricity markets, particularly retail markets. The article focuses on bilateral trading and describes some important features of an agent-based system for bilateral contracting. Special attention is devoted to the characteristics and negotiation behaviour of Buyer and Seller agents.
- Bilateral negotiation in a multi-agent supply chain systemPublication . Lopes, Fernando; Coelho, HelderA supply chain is a set of organizations directly linked by flows of services from suppliers to customers. Supply chain activities range from the ordering and receipt of raw materials to the production and distribution of finished goods. Supply chain management is the integration of key activities across a supply chain for the purposes of building competitive infrastructures, synchronizing supply with demand, and leveraging worldwide logistics. This paper addresses the challenges created by supply chain management towards improving long-term performance of companies. It presents a multi-agent supply chain system composed of multiple software agents, each responsible for one or more supply chain activities, and each interacting with other agents in the execution of their responsibilities. Additionally, this paper presents the key features of a negotiation model for software agents. The model handles bilateral multi-issue negotiation and incorporates an alternating offers protocol, a set of logrolling strategies, and a set of negotiation tactics.
- Concession behaviour in automated negotiationPublication . Lopes, Fernando; Coelho, HelderTraditional negotiation, conducted face-to-face and via mail or telephone, is often difficult to manage, prone to misunderstanding, and time consuming. Automated negotiation promises a higher level of process efficiency, and more importantly, a faster emergence and a higher quality of agreements. The potential monetary impact has led to an increasing demand for systems composed of software agents representing individuals or organizations and capable of reaching efficient agreements. At present, work on automated negotiation has generated many useful ideas and concepts leading to important theories and systems. Yet, the design of software agents with negotiation competence largely lacks systematic, traceable, and reproducible approaches, and thus remains more an art than a science. Against this background, this paper presents a model for software agents that handles two-party and multi-issue negotiation. The model incorporates various concession strategies and negotiation tactics. Concession strategies are computationally tractable functions that define the tactics to be used both at the outset and throughout negotiation. Tactics, in turn, are functions that specify the short-term moves to be made at each point of negotiation.
- Electricity markets with increasing levels of renewable generation: structure, operation, agent-based simulation and emerging designsPublication . Lopes, Fernando; Coelho, HelderABSTRACT: This book describes the common ground between electricity markets (EMs) and software agents (or artificial intelligence generally). It presents an up-to-date introduction to EMs and intelligent agents, and offers a comprehensive description of the research advances and key achievements related to existing and emerging market designs to reliably and efficiently manage the potential challenges of variable generation (VG). Most EMs are unique in their complex relationships between economics and the physics of energy, but were created without the notion that large penetrations of variable generation (VG) would be part of the supply mix. An advanced multi-agent approach simulates the behavior of power markets over time, particularly markets with large-scale penetrations of renewable resources. It is intended as a reference book for researchers, academics and industry practitioners, but given the scope of the chapters and the highly accessible style, the book also provides a coherent foundation for several different graduate courses.
- Interdisciplinary approach to automated negotiation: a preliminary reportPublication . Lopes, Fernando; Novais, Augusto Q.; Coelho, HelderAutonomous agents with negotiation competence are becoming increasingly important and pervasive. This paper follows an interdisciplinary approach to build autonomous negotiating agents by considering both game-theoretic techniques and bargaining procedures from the social sciences. The paper presents a generic model that handles bilateral multi-issue negotiation, describes equilibrium strategies for the bargaining game of alternating offers, and formalizes important strategies used by human negotiators. Autonomous agents equipped with the model are able to negotiate under both complete and incomplete information, thereby making them very compelling for automated negotiation.
- The evolution of negotiation and impasse in two-party multi-issue bargainingPublication . Lopes, Fernando; Novais, Augusto Q.; Coelho, HelderAutomated negotiation systems are becoming increasingly important and pervasive. Most previous research on automated negotiation has focused on understanding and formalizing “successful” negotiations, i.e., negotiations that do not become contentious to the point of impasse. This paper shifts the emphasis to negotiations that are “difficult” to resolve and can hit an impasse. It analyses a situation where two agents bargain over the division of the surplus of several distinct issues to demonstrate how a procedure to avoid impasses can be utilized in a specific negotiation setting. The procedure is based on the addition of new issues to the agenda during the course of negotiation and the exploration of the differences in the valuation of these issues to capitalize on Pareto optimal agreements. This paper also lays the foundation for performing an experiment to investigate how the evolution of negotiation contributes to the avoidance of impasses, paying particular attention to the expansion of the number of issues to be deliberated and its impact on the frequency of impasses
- Towards an interdisciplinary framework for automated negotiationPublication . Lopes, Fernando; Novais, Augusto Q.; Coelho, HelderNegotiation is an important and pervasive form of social interaction. The design of autonomous negotiating agents involves the consideration of insights from multiple relevant research areas to integrate different perspectives on negotiation. As a starting point for an interdisciplinary research effort, this paper presents a model that handles bilateral multi-issue negotiation, employs game-theoretic techniques to define equilibrium strategies for the bargaining game of alternating offers, and formalizes a set of negotiation strategies and tactics studied in the social sciences. Autonomous agents equipped with the model are currently being developed using the Jade framework. The agents are able to negotiate under both complete and incomplete information, thereby making the model in particular and the agents in general very compelling for automated negotiation