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Basis of a computer game that consists of choosing sources for the expansion of eletric capacity
Get PDFAn interactive computer game can show to the average citizen concepts that make the electric power planning
unique. There are so many variables, relations and constrains in this planning that it is impossible for the nontechnical citizen to answer with rationality. Interested in winning the game, players allocate generation sources to meet the expanding electric market in order to achieve economic goals as well as minimize social and environmental damages. At the beginning of the game, the players must choose exactly what objectives are to be accomplished, for example, the cheapest electrical energy or the lowest investment of the electric sector or the minimum rate of CO2 emissions or any other output. Obviously, the player that makes the better choices is the champion. At the end of the game, the players will understand all the consequences of their choices. As a collateral effect, they will also realize that electrical planning have not the same characteristics of other planning activities. The objective of expanding capacity with minimum economic, social and environmental impacts, the information about the main generating sources and the demand requirements represent the basis for the development of this planning model. Many of them are shown throughout this work. So, this work describes conceptually the game, which is, in deed, a consequence of the defined planning model. After the definition stage, a computer technician can develop the appropriate program for the game. With the use of this game, the choice of the sources is taken more rationally and the subjective aspects have less influence in the decision process. As added benefit, the players will also learn that each generation source has its positive and negative aspects
Um estudo simplificado sobre a percepção pública na área nuclear: sugestões para campanhas educativas para os diferentes segmentos da sociedade
No full textNos últimos anos, a necessidade do aumento da produção de energia elétrica,
tanto no Brasil quanto no mundo, tem encorajado os debates acerca da degradação do
meio ambiente. Em razão desses debates, órgãos governamentais e Organizações Não
Governamentais (ONG´s) encomendaram inúmeras pesquisas de opinião visando medir e
avaliar o conhecimento e percepção do público em relação às melhores fontes, e não
poluentes, de energia. No Brasil, essas pesquisas, antes de 2001, não fariam sentido,
pois sua malha energética, na grande maioria, é constituída por usinas hidrelétricas, em
outras palavras, fonte de energia renovável. Porém, quando neste mesmo ano ocorreu
uma estiagem, os órgãos competentes viram-se diante da necessidade de desenvolver
um plano, chamado de Plano Nacional de Energia (PNE2030), que recomenda entre
outros objetivos, a finalização de Angra 3 e a implantação de novas usinas nucleares em
lugares ainda a serem determinados. Considerando a complexidade do tema, o presente
trabalho apresenta uma pesquisa de campo realizada no período compreendido entre 28
de setembro a 28 de outubro de 2010 do atual nível de percepção dos brasileiros,
residentes em três municípios do Estado do Rio de Janeiro, sobre a área nuclear e como
desdobramento sugere como os órgãos competentes deveriam proceder para alcançarem de forma eficaz, através de campanhas de comunicação informativas e educativas, o
maior entendimento da população sobre o referido assunto.During the last years the need for the increase in the electricity energy
production as much as in Brazil as in the rest of the world, has raised the tone
of the debate about the environmental impact. As a result of these debates, the
government and the Non-Governmental Organizations (NGO´s) have requested
innumerous opinion researches aiming at measuring and evaluating the
knowledge and perception of the public in relation to the best non-polluting
energy sources. Prior to 2001 these researches would not make any sense in
Brazil as the majority of its power grid is made of hydroelectric plants, a
renewable energy source. However, when in that year it occurred a drought, the
competent authorities have faced the necessity of developing a plan, the
National Energy Plan (PNE2030) which recommends, among other objectives,
finalizing the construction of the Angra 3 plant and the implementation of new
nuclear plants in places still to be determined. Even considering the complexity
of the subject, this paper presents a field research realized from 28th September
2010 to 28th October 2010 of the current level of perception of the Brazilian
population, specifically the residents of three cities of Rio de Janeiro, about the
nuclear area. As a result of this work, it is suggested how the competent
authorities should proceed to reach in an efficient manner, by means of
communication campaigns both informative and educational, a greater
understanding of the population about the proposed subject
Adaptive remeshing in 2D Neutron Diffusion using external. Programs: GenMesh and Triangle
No full textO objetivo deste trabalho é apresentar não só uma ferramenta que propicie uma melhor precisão na solução no caso da análise the difusão neutronica mas também apresentar alguns resultados numa bem simplificada análise de cinética espacial. Para este primeiro objetivo, um indicador de erro baseado na continuidade da corrente de neutrons nas interfaces inter-elçementos é apresentada e alguns resultados baseados na remalhagem adaptativa são apresentados no caso 2D utilizando programas externos tais como GenMesh (com limitações no numero de
materiais) e Triangle. Para alcançar o segundo objetivo foi necessário inserir a cinética pontual no pograma MEF. Alguns exemplos de cinética pontual são apresentados no intuit de certificar que os resultados apresentados pelo programa MEF estão em acordo com aqueles apresentados por outros autores. Finalmente, uma análise bem
simplificada de cinética espacial é realizada em um reator cujas seções de choque, correspondentes a duas regiões
diferentes do núcleo, variam de um forma senoidal com fases diferentes
GPU-based Monte Carlo simulation in neutron transport and finite differences heat equation evaluation
No full textRadiation dose rate map interpolation in nuclear plants using neural networks and virtual reality techniques
No full textFUZZY CONTROL APPLIED TO NUCLEAR POWER PLANT PRESSURIZER SYSTEM
No full textEm um reactor de água pressurizada (PWR) usinas nucleares (centrais nucleares), o controle da pressão no circuito primário é muito importante para manter o reator em uma condição de segurança e melhorar a eficiência do processo de geração. o
principal componente responsável por esta tarefa é o pressurizador. O sistema de controle de pressão pressurizador (PPCS)
utiliza aquecedores e válvulas de pulverização, para manter a pressão dentro de uma banda de operação durante o estado estacionário
condições, e limita as alterações de pressão, durante condições transitórias. As válvulas de alívio de segurança e fornecer
proteção contra sobrepressão para o sistema de refrigeração do reator (RCS) para garantir a integridade do sistema. Vários protetora
viagens de reatores são gerados se os parâmetros do sistema exceder os limites de segurança. Historicamente, a proporcional-integralidade
controlador derivado (PID) é usado em PWR para manter a pressão no ponto de ajuste, durante cuja operação
condições. O objetivo do presente estudo tem dois objetivos principais: primeiro é desenvolver um modelo baseado em pressurizador
redes neurais artificiais (RNAs); segundo é o de desenvolver um controlador fuzzy para a pressão do pressurizador PWR, e comparar o seu desempenho com o controlador P. Os dados de uma planta simulador PWR foi utilizado para testar a RNA e
os controladores bem. O simulador de referência é um Westinghouse usina PWR 3-ciclo com a saída térmica total
de 2.785 MW térmicos. Os resultados das simulações mostram que a resposta pressurizador modelo ANN estão em razoável
acordo com a usina simulado, e o controlador fuzzy construído neste estudo tem melhor desempenho
em comparação com o controlador P.In a pressurized water reactor (PWR) nuclear power plants (NPPs) the pressure control in the primary loop is
very important for keeping the reactor in a safety condition and improve the generation process efficiency. The
main component responsible for this task is the pressurizer. The pressurizer pressure control system (PPCS)
utilizes heaters and spray valves to maintain the pressure within an operating band during steady state
conditions, and limits the pressure changes, during transient conditions. Relief and safety valves provide
overpressure protection for the reactor coolant system (RCS) to ensure system integrity. Various protective
reactor trips are generated if the system parameters exceed safe bounds. Historically, a proportional-integral-derivative (PID) controller is used in PWRs to keep the pressure in the set point, during those operation
conditions. The purpose of this study has two main goals: first is to develop a pressurizer model based on
artificial neural networks (ANNs); second is to develop a fuzzy controller for the PWR pressurizer pressure, and
compare its performance with the P controller. Data from a simulator PWR plant was used to test the ANN and
the controllers as well. The reference simulator is a Westinghouse 3-loop PWR plant with a total thermal output of 2785 MWth. The simulation results show that the pressurizer ANN model response are in reasonable
agreement with the simulated power plant, and the fuzzy controller built in this study has better performance
compared to the P controller
A hardware architecture for subtractive clustering.
No full textAlgoritmos de agrupamento são usados extensivamente para organizar e classificar os dados abundantes. Este artigo descreve a implementação do algoritmo de agrupamento subtrativo em hardware. A solução desenvolvida neste trabalho busca uma implementação de hardware para identificação automática e rápida de centros de cluster. Este equipamento proposto é genérico para que ele possa ser usado em todos os problemas de classificação de dados, omnipresente em sistemas de identificação.Clustering algorithms are used extensively to organise and categorise abundant data. This paper describes the implementation of subtractive clustering algorithm in hardware. The solution developed in this paper seeks a hardware implementation to automatic and fast identification of cluster centres. This hardware proposed is generic so it can be used in any data classification problems, omnipresent in identification systems
THEWASP Library Thermodynamic Water & Steam Properties Library in GPU.
Get PDFIn this paper we present a new library for thermodynamic evaluation of water properties, THEWASP. This library consists of a C++ and CUDA [13] based programs used to accelerate a function evaluation using GPU and GPU clusters. Global optimization problems need thousands of evaluations of the objective functions to find the global optimum implying in several days of expensive processing. This problem motivates us to seek a way to speed up our code, as well as to use MPI on Beowulf clusters [5] [17], which however increases the cost in terms of electricity, air conditioning and others. The GPU based programming can accelerate the implementation up to 100 times[7] and help increase the number of evaluations in global optimization problems using, for example, the PSO[8] or DE[15] Algorithms. THEWASP is based on Water-Steam formulations publish by the International Association for the properties of water and steam, Lucerne - Switzerland[2] [16], and provides several temperature and pressure function evaluations, such as specific heat, specific enthalpy, specific entropy and also some inverse maps. In this study we evaluated the gain in speed and performance and compared it a CPU based processing library
On Brazil’s participation in the first ten years of the INPRO project and perspectives ahead.
Get PDFIn September 2001, the International Atomic Energy Agency (IAEA) launched the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO) to help ensure that nuclear energy is available to contribute to meeting the world energy needs of the 21st century in a sustainable manner. To achieve its objective INPRO brings together technology holders and technology users to consider jointly the international and the national actions to achieve the desired innovations in nuclear reactors, fuel cycles and institutional approaches. This paper reviews INPRO’s main achievements in its first ten years of existence and highlights Brazil’s contributions to the project and the benefits gained from its membership. Among INPRO’s main
achievements are the development of the INPRO assessment methodology, key studies and collaborative project results, and the establishment of the Dialogue Forum between technology holders and technology users. Brazil contributed to the project by providing a cost-free expert to the INPRO Coordination Group in 2002, by performing an assessment of two small sized reactors for deployment in the country using INPRO methodology published in 2009, and by participating in two collaborative projects related to technology innovations, which shall be completed by the end of this year. The paper concludes with a short presentation of the opportunities for the country’s participation in the activities of the INPRO Action Plan for the biennium 2012-2013, currently under preparation
Evaluation of Transport Properties of Nanofiltration Membranes Exposed to Radioactive Liquid Waste
Get PDFThe application of membrane separation processes (PSM) for treatment of radioactive waste requires the
selection of a suitable membrane for the treatment of waste, as the membrane will be directly exposed to the
radioactive liquid waste, and also exposed to ionizing radiation. The nanofiltration membrane is most suitable
for treatment of radioactive waste, since it has high rejection of multivalent ions. Usually the membranes are
made of polymers and depending on the composition of the waste, type and dose of radiation absorbed may be changes in the structure of the membrane, resulting in loss of its transport properties. We tested two commercial nanofiltration membranes: NF and SW Dow/Filmtec. The waste liquid used was obtained in the process of conversion of uranium hexafluoride gas to solid uranium dioxide, known as "carbonated water". The membranes were characterized as their transport properties (hydraulic permeability, permeate flux and salt rejection) before and after their immersion in the waste for 24 hours. The surface of the membranes was also evaluated by SEM and FTIR. It was observed that in both the porosity of the membrane selective layer was altered, but not the membrane surface charge, which is responsible for the selectivity of the membrane. The NF membranes and SW showed uranium ion rejection of 64% and 55% respectively