995 resultados para Virtual Organizations


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Relatório de Estágio apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ciências da Informação e da Documentação

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Demand response is assumed as an essential resource to fully achieve the smart grids operating benefits, namely in the context of competitive markets and of the increasing use of renewable-based energy sources. Some advantages of Demand Response (DR) programs and of smart grids can only be achieved through the implementation of Real Time Pricing (RTP). The integration of the expected increasing amounts of distributed energy resources, as well as new players, requires new approaches for the changing operation of power systems. The methodology proposed in this paper aims the minimization of the operation costs in a distribution network operated by a virtual power player that manages the available energy resources focusing on hour ahead re-scheduling. When facing lower wind power generation than expected from day ahead forecast, demand response is used in order to minimize the impacts of such wind availability change. In this way, consumers actively participate in regulation up and spinning reserve ancillary services through demand response programs. Real time pricing is also applied. The proposed model is especially useful when actual and day ahead wind forecast differ significantly. Its application is illustrated in this paper implementing the characteristics of a real resources conditions scenario in a 33 bus distribution network with 32 consumers and 66 distributed generators.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper proposes a wind speed forecasting model that contributes to the development and implementation of adequate methodologies for Energy Resource Man-agement in a distribution power network, with intensive use of wind based power generation. The proposed fore-casting methodology aims to support the operation in the scope of the intraday resources scheduling model, name-ly with a time horizon of 10 minutes. A case study using a real database from the meteoro-logical station installed in the GECAD renewable energy lab was used. A new wind speed forecasting model has been implemented and it estimated accuracy was evalu-ated and compared with a previous developed forecast-ing model. Using as input attributes the information of the wind speed concerning the previous 3 hours enables to obtain results with high accuracy for the wind short-term forecasting.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The integration of growing amounts of distributed generation in power systems, namely at distribution networks level, has been fostered by energy policies in several countries around the world, including in Europe. This intensive integration of distributed, non-dispatchable, and natural sources based generation (including wind power) has caused several changes in the operation and planning of power systems and of electricity markets. Sometimes the available non-dispatchable generation is higher than the demand. This generation must be used; otherwise it is wasted if not stored or used to supply additional demand. New policies and market rules, as well as new players, are needed in order to competitively integrate all the resources. The methodology proposed in this paper aims at the maximization of the social welfare in a distribution network operated by a virtual power player that aggregates and manages the available energy resources. When facing a situation of excessive non-dispatchable generation, including wind power, real time pricing is applied in order to induce the increase of consumption so that wind curtailment is minimized. This method is especially useful when actual and day-ahead resources forecast differ significantly. The distribution network characteristics and concerns are addressed by including the network constraints in the optimization model. The proposed methodology has been implemented in GAMS optimization tool and its application is illustrated in this paper using a real 937-bus distribution network with 20.310 consumers and 548 distributed generators, some of them non-dispatchable and with must take contracts. The implemented scenario corresponds to a real day in Portuguese power system.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Power systems have been through deep changes in recent years, namely due to the operation of competitive electricity markets in the scope the increasingly intensive use of renewable energy sources and distributed generation. This requires new business models able to cope with the new opportunities that have emerged. Virtual Power Players (VPPs) are a new type of player that allows aggregating a diversity of players (Distributed Generation (DG), Storage Agents (SA), Electrical Vehicles (V2G) and consumers) to facilitate their participation in the electricity markets and to provide a set of new services promoting generation and consumption efficiency, while improving players’ benefits. A major task of VPPs is the remuneration of generation and services (maintenance, market operation costs and energy reserves), as well as charging energy consumption. This paper proposes a model to implement fair and strategic remuneration and tariff methodologies, able to allow efficient VPP operation and VPP goals accomplishment in the scope of electricity markets.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Electricity Markets are not only a new reality but an evolving one as the involved players and rules change at a relatively high rate. Multi-agent simulation combined with Artificial Intelligence techniques may result in very helpful sophisticated tools. This paper presents a new methodology for the management of coalitions in electricity markets. This approach is tested using the multi-agent market simulator MASCEM (Multi-Agent Simulator of Competitive Electricity Markets), taking advantage of its ability to provide the means to model and simulate Virtual Power Players (VPP). VPPs are represented as coalitions of agents, with the capability of negotiating both in the market and internally, with their members in order to combine and manage their individual specific characteristics and goals, with the strategy and objectives of the VPP itself. A case study using real data from the Iberian Electricity Market is performed to validate and illustrate the proposed approach.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents a decision support tool methodology to help virtual power players (VPPs) in the Smart Grid (SGs) context to solve the day-ahead energy resource scheduling considering the intensive use of Distributed Generation (DG) and Vehicle-To-Grid (V2G). The main focus is the application of a new hybrid method combing a particle swarm approach and a deterministic technique based on mixedinteger linear programming (MILP) to solve the day-ahead scheduling minimizing total operation costs from the aggregator point of view. A realistic mathematical formulation, considering the electric network constraints and V2G charging and discharging efficiencies is presented. Full AC power flow calculation is included in the hybrid method to allow taking into account the network constraints. A case study with a 33-bus distribution network and 1800 V2G resources is used to illustrate the performance of the proposed method.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Progress in Industrial Ecology, An International Journal, nº 4(5), p. 363-381

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A forma como aprendemos depende do contexto tecnológico e sociocultural que nos rodeia, actualmente a inclusão de tecnologia recente na sala de aula não é mais considerada opcional, mas sim uma necessidade pois a forma como o aluno aprende está em constante evolução. Tendo em atenção esta necessidade, foi desenvolvido no decorrer desta tese um simulador em realidade virtual que utiliza comandos/interfaces hápticos. O objectivo deste simulador é ensinar conceitos de física de forma interactiva. Os dispositivos hápticos permitem adicionar o sentido táctil ou de toque à interacção entre homem e máquina, permitindo assim aceder a novas sensações relativas ao seu uso nomeadamente com objectivos de aprendizagem. O simulador desenvolvido designado por “Forces of Physics” aborda três tipos de forças da física: forças de atrito, forças gravitacionais e forças aerodinâmicas. Cada tipo de força corresponde a um módulo do simulador contendo uma simulação individual em que são explicados conceitos específicos dessa força num ambiente visual estimulante e com uma interacção mais realista devido à inclusão do dispositivo háptico Novint Falcon. O simulador foi apresentado a vários utilizadores bem como á comunidade científica através de apresentações em conferências. A avaliação foi realizada com recurso a um questionário com dez perguntas, cinco de sobre aprendizagem e cinco sobre a utilização, tendo sido preenchido por 14 utilizadores. O simulador obteve uma boa recepção por parte dos utilizadores, tendo vários utilizadores expressado as suas opiniões sobre estado actual do simulador, do futuro do mesmo e da respectiva validade para uso na sala de aula.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article describes a study that investigated the main strategic drivers that influence the implementation of sustainability/social responsibility programs. An online survey was administered to managers of Portuguese organizations with certified management systems. The findings suggest that the implementation of such programs is mainly correlated to: 1.) the approach to understanding and working toward the satisfaction of the community’s needs (in the broad sense of social responsibility); 2.) how systematically sustainability within the organization is identified and managed (e.g., pollution prevention, improved environmental performance, and compliance with the applicable environmental laws); and 3.) the degree to which the organization tries to understand the needs of the employees and works toward satisfying them. In addition to the survey, five interviews with top managers of the surveyed organizations provided some useful insights. There was no consensus on the meaning of sustainability and social responsibility: some described it as an instrumental approach for obtaining better organizational results, while others regarded it as the right thing to do (i.e., it is values driven). In all cases, however, the managers supported a kind of umbrella construct under which different size corporations use different models (for example, the Dow Jones Sustainability Index (DJSI), Global Reporting Initiative (GRI), ISO 14001 environmental management systems), although some managers reported that they simply do not know what to do. All of those surveyed agreed that the lack of a systematic approach could represent a major threat to their organization, making them willing to pay more attention and take more action on the issue of sustainability. An additional suggestion made by managers was to change from a triple bottom line (economic dimension, environmental dimension, social equity dimension) to a quadruple bottom line by adding another dimension: personal and family happiness. This fourth dimension was recognized by the Greek philosopher/thinker Aristotle (384-322 BCE) who thought of happiness as the highest good (virtue) and ultimate goal and purpose of life, achieved through living well, in harmony. Such harmony suggests a balance and a lack of excess—in other words a sustainable existence.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

As neurociências aliadas ao marketing, constituem um novo paradigma com grande potencial, no que diz respeito ao conhecimento profundo do consumidor e do seu comportamento de compra: o Neuromarketing. O Neuromarketing tem uma forte componente científica que estuda e define fisiologicamente os mecanismos subjacentes à cognição, com foco específico nas bases neurais dos processos mentais e suas manifestações comportamentais e uma componente económica e social em que os Marketeers se questionam acerca dos métodos tradicionais para conhecer profundamente o seu cliente e aplicar em toda a sua potencialidade o marketing one-to-one, criar relações de fidelidade e evitar a falta de diferenciação que ainda se verifica em algumas empresas. Na óptica do consumidor este tema é ainda desconhecido e podemos afirmar com alguma certeza que também será um pouco assustador pensar que seja possível conhecer tão bem o nosso cérebro e a nossa maneira de pensar enquanto consumidores, que nos consigam “manipular” no momento da decisão de compra. O presente estudo tem como finalidade perceber o que pensa o consumidor desta nova área, o que sente em relação aos métodos usados em Neuromarketing e se já têm alguma percepção de que diariamente já são confrontados com técnicas de Neuromarketing e ainda, o que pensam delas.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tese de Doutoramento em Didática e Formação

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Web 2.0 software in general and wikis in particular have been receiving growing attention as they constitute new and powerful tools, capable of supporting information sharing, creation of knowledge and a wide range of collaborative processes and learning activities. This paper introduces briefly some of the new opportunities made possible by Web 2.0 or the social Internet, focusing on those offered by the use of wikis as learning spaces. A wiki allows documents to be created, edited and shared on a group basis; it has a very easy and efficient markup language, using a simple Web browser. One of the most important characteristics of wiki technology is the ease with which pages are created and edited. The facility for wiki content to be edited by its users means that its pages and structure form a dynamic entity, in permanent evolution, where users can insert new ideas, supplement previously existing information and correct errors and typos in a document at any time, up to the agreed final version. This paper explores wikis as a collaborative learning and knowledge-building space and its potential for supporting Virtual Communities of Practice (VCoPs). In the academic years (2007/8 and 2008/9), students of the Business Intelligence module at the Master's programme of studies on Knowledge Management and Business Intelligence at Instituto Superior de Estatistica e Gestao de Informacao of the Universidade Nova de Lisboa, Portugal, have been actively involved in the creation of BIWiki - a wiki for Business Intelligence in the Portuguese language. Based on usage patterns and feedback from students participating in this experience, some conclusions are drawn regarding the potential of this technology to support the emergence of VCoPs; some provisional suggestions will be made regarding the use of wikis to support information sharing, knowledge creation and transfer and collaborative learning in Higher Education.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: The purpose of this article is to discuss the impact of Supplier orientation and the resulting Supply Chain Management (SCM) approach, on the organizational performance of ISO 9001 Quality Management Systems certified organizations. Methodology/Approach: Following a literature review, a full structural conceptual model was proposed. An online survey was administered to managers of Portuguese organizations with certified ISO 9001 Quality Management Systems. Descriptive Statistics and Structural Model Equations were used to validate the proposed conceptual model. Findings: There are positive relationships between Organization Strategy and Supplier Orientation, between Supplier Orientation and Stakeholders Satisfaction, and between Stakeholders Satisfaction and Organizational Performance Orientation, supporting ISO 9001:2015. These findings provide insights that supplier orientation, mediated by stakeholder satisfaction, is an essential tool for organizational competitive sustainable advantage. Research Limitation/implication: The analysis was based on managers of ISO 9001 certified organizations perceptions, so additional studies with actual data and longitudinal studies should be useful for further validation. Originality/Value of paper: The importance of the overall organizational ecosystem is highlighted with potential impact on the more than 1 Million ISO 9001 organizations certified worldwide and in their suppliers.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Smart Grids (SGs) have emerged as the new paradigm for power system operation and management, being designed to include large amounts of distributed energy resources. This new paradigm requires new Energy Resource Management (ERM) methodologies considering different operation strategies and the existence of new management players such as several types of aggregators. This paper proposes a methodology to facilitate the coalition between distributed generation units originating Virtual Power Players (VPP) considering a game theory approach. The proposed approach consists in the analysis of the classifications that were attributed by each VPP to the distributed generation units, as well as in the analysis of the previous established contracts by each player. The proposed classification model is based in fourteen parameters including technical, economical and behavioural ones. Depending of the VPP strategies, size and goals, each parameter has different importance. VPP can also manage other type of energy resources, like storage units, electric vehicles, demand response programs or even parts of the MV and LV distribution network. A case study with twelve VPPs with different characteristics and one hundred and fifty real distributed generation units is included in the paper.