982 resultados para reality management
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A multilevel negotiation mechanism for operating smart grids and negotiating in electricity markets considers the advantages of virtual power player management.
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Currently, power systems (PS) already accommodate a substantial penetration of distributed generation (DG) and operate in competitive environments. In the future, as the result of the liberalisation and political regulations, PS will have to deal with large-scale integration of DG and other distributed energy resources (DER), such as storage and provide market agents to ensure a flexible and secure operation. This cannot be done with the traditional PS operational tools used today like the quite restricted information systems Supervisory Control and Data Acquisition (SCADA) [1]. The trend to use the local generation in the active operation of the power system requires new solutions for data management system. The relevant standards have been developed separately in the last few years so there is a need to unify them in order to receive a common and interoperable solution. For the distribution operation the CIM models described in the IEC 61968/70 are especially relevant. In Europe dispersed and renewable energy resources (D&RER) are mostly operated without remote control mechanisms and feed the maximal amount of available power into the grid. To improve the network operation performance the idea of virtual power plants (VPP) will become a reality. In the future power generation of D&RER will be scheduled with a high accuracy. In order to realize VPP decentralized energy management, communication facilities are needed that have standardized interfaces and protocols. IEC 61850 is suitable to serve as a general standard for all communication tasks in power systems [2]. The paper deals with international activities and experiences in the implementation of a new data management and communication concept in the distribution system. The difficulties in the coordination of the inconsistent developed in parallel communication and data management standards - are first addressed in the paper. The upcoming unification work taking into account the growing role of D&RER in the PS is shown. It is possible to overcome the lag in current practical experiences using new tools for creating and maintenance the CIM data and simulation of the IEC 61850 protocol – the prototype of which is presented in the paper –. The origin and the accuracy of the data requirements depend on the data use (e.g. operation or planning) so some remarks concerning the definition of the digital interface incorporated in the merging unit idea from the power utility point of view are presented in the paper too. To summarize some required future work has been identified.
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Intensive use of Distributed Generation (DG) represents a change in the paradigm of power systems operation making small-scale energy generation and storage decision making relevant for the whole system. This paradigm led to the concept of smart grid for which an efficient management, both in technical and economic terms, should be assured. This paper presents a new approach to solve the economic dispatch in smart grids. The proposed methodology for resource management involves two stages. The first one considers fuzzy set theory to define the natural resources range forecast as well as the load forecast. The second stage uses heuristic optimization to determine the economic dispatch considering the generation forecast, storage management and demand response
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OBJECTIVE: Various support measures useful for promoting joint change approaches to the improvement of both shiftworking arrangements and safety and health management systems were reviewed. A particular focus was placed on enterprise-level risk reduction measures linking working hours and management systems. METHODS: Voluntary industry-based guidelines on night and shift work for department stores and the chemical, automobile and electrical equipment industries were examined. Survey results that had led to the compilation of practicable measures to be included in these guidelines were also examined. The common support measures were then compared with ergonomic checkpoints for plant maintenance work involving irregular nightshifts. On the basis of this analysis, a new night and shift work checklist was designed. RESULTS: Both the guidelines and the plant maintenance work checkpoints were found to commonly cover multiple issues including work schedules and various job-related risks. This close link between shiftwork arrangements and risk management was important as shiftworkers in these industries considered teamwork and welfare services to be essential for managing risks associated with night and shift work. Four areas found suitable for participatory improvement by managers and workers were work schedules, ergonomic work tasks, work environment and training. The checklist designed to facilitate participatory change processes covered all these areas. CONCLUSIONS: The checklist developed to describe feasible workplace actions was suitable for integration with comprehensive safety and health management systems and offered valuable opportunities for improving working time arrangements and job content together.
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The smart grid concept is rapidly evolving in the direction of practical implementations able to bring smart grid advantages into practice. Evolution in legacy equipment and infrastructures is not sufficient to accomplish the smart grid goals as it does not consider the needs of the players operating in a complex environment which is dynamic and competitive in nature. Artificial intelligence based applications can provide solutions to these problems, supporting decentralized intelligence and decision-making. A case study illustrates the importance of Virtual Power Players (VPP) and multi-player negotiation in the context of smart grids. This case study is based on real data and aims at optimizing energy resource management, considering generation, storage and demand response.
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Energy Resources Management can play a very relevant role in future power systems in SmartGrid context, with high penetration of distributed generation and storage systems. This paper deals with the importance of resources management in incident situation. The system to consider a high penetration of distributed generation, demand response, storage units and network reconfiguration. A case study evidences the advantages of using a flexible SCADA to control the energy resources in incident situation.
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Energy resources management can play a very relevant role in future power systems in a SmartGrid context, with intensive penetration of distributed generation and storage systems. This paper deals with the importance of resource management in incident situations. The paper presents DemSi, an energy resources management simulator that has been developed by the authors to simulate electrical distribution networks with high distributed generation penetration, storage in network points and customers with demand response contracts. DemSi is used to undertake simulations for an incident scenario, evidencing the advantages of adequately using flexible contracts, storage, and reserve in order to limit incident consequences.
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In the energy management of a small power system, the scheduling of the generation units is a crucial problem for which adequate methodologies can maximize the performance of the energy supply. This paper proposes an innovative methodology for distributed energy resources management. The optimal operation of distributed generation, demand response and storage resources is formulated as a mixed-integer linear programming model (MILP) and solved by a deterministic optimization technique CPLEX-based implemented in General Algebraic Modeling Systems (GAMS). The paper deals with a vision for the grids of the future, focusing on conceptual and operational aspects of electrical grids characterized by an intensive penetration of DG, in the scope of competitive environments and using artificial intelligence methodologies to attain the envisaged goals. These concepts are implemented in a computational framework which includes both grid and market simulation.
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This paper addresses the optimal involvement in derivatives electricity markets of a power producer to hedge against the pool price volatility. To achieve this aim, a swarm intelligence meta-heuristic optimization technique for long-term risk management tool is proposed. This tool investigates the long-term opportunities for risk hedging available for electric power producers through the use of contracts with physical (spot and forward contracts) and financial (options contracts) settlement. The producer risk preference is formulated as a utility function (U) expressing the trade-off between the expectation and the variance of the return. Variance of return and the expectation are based on a forecasted scenario interval determined by a long-term price range forecasting model. This model also makes use of particle swarm optimization (PSO) to find the best parameters allow to achieve better forecasting results. On the other hand, the price estimation depends on load forecasting. This work also presents a regressive long-term load forecast model that make use of PSO to find the best parameters as well as in price estimation. The PSO technique performance has been evaluated by comparison with a Genetic Algorithm (GA) based approach. A case study is presented and the results are discussed taking into account the real price and load historical data from mainland Spanish electricity market demonstrating the effectiveness of the methodology handling this type of problems. Finally, conclusions are dully drawn.
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A mobilidade é considerada um dos factores chave na sustentabilidade e desenvolvimento de qualquer economia. Em Portugal essa realidade não é diferente. Em 2011 verifica-se que 41% do consumo global de combustíveis pertence ao sector rodoviário [1] o que evidencia a sua relevância na economia do país. No que concerne aos veículos de tracção eléctrica, começaram a surgir nos finais do séc. XIX, e no início do séc. XX nos Estados Unidos da América representavam 38% dos veículos [2]. Diversos factores económicos e tecnológicos conduziram a um crescente desinteresse por parte da indústria em investir na produção deste tipo de veículos. Contudo com a introdução de baterias de iões de lítio em veículos de tracção eléctrica, torna-os viáveis e competitivos. Neste trabalho é proposto o desenvolvimento de um sistema de gestão de baterias de iões de lítio do tipo LiFePO4 para aplicação em veículos eléctricos. O sistema deverá assegurar a protecção das baterias e indicar o estado de carga das mesmas. Este sistema permitirá uma optimização no uso deste género de baterias, proporcionará uma melhor utilização, aumentando a sua vida útil. O sistema irá ser aplicado e testado experimentalmente no veículo eléctrico ecológico (Veeco). No âmbito do projecto Veeco foi projectado e construído um banco de ensaios utilizado na análise do comportamento das baterias, e determinar quais os requisitos necessários para o sistema de gestão desenvolvido. Foi também projectado e realizado um sistema de aquisição e processamento de dados que permite obter informações acerca da bateria, dados que estarão disponíveis no interface Homem-máquina do Veeco.
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Sendo os desperdícios “Waste” associados à atividade industrial em Portugal e nos mercados globais e os seus custos inerentes, uma das maiores preocupações a todos os níveis de gestão empresarial, a filosofia “Lean” nasce como ajuda e encaminhamento na solução desta problemática. O conceito “Lean”, no que se refere à indústria, desde sempre e até aos dias de hoje, tem uma enorme ênfase, com a adoção deste conceito.Verificam-se bons resultados ao nível da redução de custos, melhoria da qualidade geral dos artigos produzidos, no controlo da produção em geral e é uma poderosa ferramenta no estreitamento da relação entre os diferentes intervenientes da cadeia de valor de determinado produto, sobretudo com fornecedores e com clientes. Com “Lean Management” e “Glass Wall Management”, em ambientes onde as empresas mais avançadas estão a procurar melhorar a sua competitividade através de uma gestão transparente (“Glass Wall Management”), a partir da qual, “toda informação relevante é compartilhada de maneira a que todos entendam a situação”(Suzaki, K, 1993), ganha cada vez mais importância a existência de uma estrutura organizacional que permita esta transparência e a consequente maturidade das empresas. Neste trabalho foram descritos alguns processos de gestão transparente desenvolvidos nos últimos dois anos numa PME portuguesa, aprofundando o processo de gestão transparente vigente e as ferramentas que ajudam a empresa e que na sua globalidade poderão ser extrapoladas a outras PME Portuguesas de modo que a informação importante e relevante seja partilhada por todos os intervenientes na estrutura empresarial, sendo entendida e desenvolvida por todos através de Edições e Revisões aos documentos mais importantes da empresa. Neste estudo foram contactadas vinte e uma PME’S portuguesas de tipologia de produção MTO (Make to Order) do sector dos estofos/mobiliário, e solicitado o preenchimento de um Questionário, tendo como fim em vista, a verificação do uso desta metodologia “Glass Wall Management” à escala empresarial portuguesa e a interpretação do Conceito Geral “Lean” como filosofia de redução de materiais, tempos e custos.
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Mestrado em Contabilidade e Gestão das Instituições Financeiras
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Mestrado em Controlo e Gestão dos Negócios
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Mestrado em Segurança e Higiene do Trabalho.
Motivations and management factors of volunteer work in nonprofit organisations: a literature review
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The objective of this paper is to review and discuss the literature about volunteers’ motivations to donate their time to NPOs and the management factors that can influence volunteer work. Firstly, the paper illustrates and compares the different types of motivation followed by a presentation of a typology that organises the volunteers’ motivations into four types: (i) altruism, (ii) belonging, (iii) ego and social recognition and (iv) development and learning. Secondly we discuss the key management factors in volunteering: recruitment, training and rewarding. Finally, we present four gaps in the literature that justify the scope for further research: (i) omission of differences between motivations related to volunteers’ "Attraction" versus "Retention"; (ii) focus of the research on the USA, UK and Australia context; (iii) absence of comparative analyses that relate motivations by NPO types and (iv) comprehension of how management factors (recruitment, training and rewarding) influence volunteers’ satisfaction and retention.