Abstract
Existing e-marketplaces, built on traditional client-server architectures, severely restrict the scope and dynamics of B2B interactions. Peer-to-peer (P2P) architectures will provide far more decentralised infrastructures, white allowing a much wider range of business patterns to take place. The purpose of this paper is twofold: (1) to argue that interaction over a P2P network better resembles the way enterprises perform business with each other, and (2) to point out a set of essential services required it) make P2P infrastructures fit for B2B exchanges. An overview of those services is presented, based on one of the leading P2P platforms (JXTA).

Abstract
This paper presents an enhanced version of an AC Fuzzy Power Flow model designed to integrate correlation data between nodal injections. The model gives the user the possibility to specify fuzzy numbers to represent the possible behavior of loads and generations and outputs fuzzy membership functions for voltage magnitudes and phases, active and reactive flows, losses and generations. The algorithm is organized in two basic steps. The first one corresponds to a linearized procedure while the second aims at introducing correlated data leading to a reduction of the width of the membership output functions. In a final section, we present results obtained with a case study based on a didactic power system to illustrate and highlight details of the proposed models.

Abstract

Abstract
Within the scope of virtual and networked enterprises, this paper introduces a novel methodology for the integration of quality management into enterprise modeling and allowing for quality certification of the whole enterprise. The ISO 9001:2000 standard is presented as an interesting starting point for the virtual enterprise quality management system implimentation. Quality management systems certification within the scope of ISO 10011 (or even ISO FDIS 19011) is however quite a difficult task. An alternative scenario for certification is therefore proposed.

Abstract
Unbundling and liberalization of the electric sector has led in many countries, including Portugal, to the settlement definition of quality standards for the power distribution systems that give rise to penalties when those standards are not met. Also, penalties and rewards related to global reliability indices exist in some countries. Distribution companies must take this into account when planning there systems because the minimization of the net reliability cost is a main criteria when making investment decisions performing reliability studies to support investment decisions, and penalties (or rewards) become direct reliability costs (or benefits), regardless of any other consideration concerning the impact of the frequency and duration of the interruptions. Most of the time, standards are defined in terms of the sum of the interruption durations during a year. In this paper, the details of this discussion are addressed, in the framework of the investment decision-making process. A formal model for the problem is proposed, along with methodologies able to tackle it. The inadequacy of a markovian approach is discussed and illustrated, showing how bad investment decisions can be made due to incorrect evaluation of the reliability costs. The discussion will be illustrated with small numerical examples.

Abstract
Defining the needs of operating reserve in a power system has been always a subject of interest, leading to the development of deterministic rules (e.g. the percentage rule defined by UCTE in Europe or the well-known "largest unit" rule) and probabilistic methods like PJM (Pennsylvania-New Jersey-Maryland) and its enhancements, based on the concept of risk. However, the recent increase in the penetration of wind power generation changed the framework of this evaluation, due to the volatile nature of this kind of energy. In this paper, a detailed model of the unavailability of wind parks that accounts both for machine failures and different wind levels is combined with the modified PJM method, in order to build a consistent framework for the evaluation of the operational risk. The paper also shows how the proposed model can be used as a decision-aid tool for planning the operational reserve, either by performing multicriteria analysis on cost and risk or by stipulating an acceptable risk level.