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Simulação virtual de visita técnica no reator argonauta para fins de divulgação científica
Get PDFDiversas instituições de Ciência e Tecnologia do estado do Rio tem desenvolvido um importante papel para a sociedade brasileira. Um exemplo destas instituições é o Instituto de Engenharia Nuclear (IEN). As atividades desenvolvidas no IEN geram produtos e serviços como fornecimento de radiofármacos, ensaios e análises de materiais, recolhimento de rejeitos radioativos e formação de recursos humanos. Entretanto, mesmo estando na era do comunicação, nem todos os cidadãos conseguem ter acesso ao conteúdo gerado nessas instituições. Diante deste cenário, não é difícil perceber que existem vários temas técnico-científicos que deveriam ser mais bem divulgados, principalmente para o público em idade escolar, para a finalidade de esclarecer dúvidas acerca do assunto, o IEN tem um programa de visita técnica agendada as suas instalações para alunos do ensino fundamental e médio. Entretanto devido a natureza de suas atividades, muitas de suas instalações tem restrição quanto ao acesso, impossibilitando muitas vezes, uma apresentação mais clara de suas finalidades. Por outro lado a Realidade Virtual (RV) é um termo usado para descrever um conjunto de técnicas, que tem como objetivo dar ao participante a máxima sensação de presença em um mundo virtual, com isso, simulações virtuais são usadas para várias finalidades, tais como reabilitação, treinamento e entretenimento, e neste caso como uma ferramenta educacional. Depois de uma pesquisa com o próprios servidores está sendo desenvolvido uma plataforma de simulação virtual do processo de visita técnica em ambiente controlado (neste caso as instalações do reator Argonauta) onde os usuários teriam uma "livre movimentação" dentro das instalações do reator, a fim de esclarecer dúvidas e ensinar sobre as fases de produção, segurança e controle do reator ao público geral. Como resultado é esperado demonstrar a importância da realidade virtual como ferramenta de conhecimento e propagação das simulações virtuais à qualquer outra instituição que possua políticas de visitação mais restritas
Desenvolvimento de sistema de proteção para reator nuclear de pesquisa baseado em field programmable gate array-FPGA
Get PDFThis study presents a implementation purpose of a protection system for research nuclear reactors by using a programed device FPGA (Field Programmable Gate Array). As well as logic protection method involved on an automatic shutdown (TRIP) of a reactor, that ensure the security on such systems. These new control and operation mechanics are developed to guarantee that the security limits of a power plant are not exceeded, these mechanics can work isolated or in groups to safe guard the security levels. For this implementation to be completed, there will be presented the main aspects and concepts referred to protection systems, mostly about research nuclear reactors, with some applications terms exposed. The system proposed at this paper was developed following the VHDL (Very High Speed Integrated Circuits) hardware describing language, and the Modelsim software from Altera Software to program the automatic turning off routines, and hypothetical simulations for such. The results show that for every software application for supporting nuclear reactors, like security devices, they have to meet the IEC 60880 criteria. This paper have great importance, seeing that nuclear reactor security systems, are a basic element for ensure the reactor security.Neste trabalho é realizado um estudo e apresentada uma proposta de implementação de um modelo de Sistema de Proteção para Reatores Nucleares de Pesquisa, através da utilização de dispositivo programável FPGA (Field Programmagle Gate Array). Bem como são estudadas as lógicas de proteção de um desligamento automático (TRIP) de um reator, que garantem a segurança nesse tipo de sistema. A utilização desses novos mecanismos de controle e operação são desenvolvidos a fim de garantir que os limites do nível de segurança de uma usina não sejam superados, logo esses mecanismos podem acontecer de maneira isolada ou em conjunto de forma a garantir a segurança. Para que essa implementação seja completa, são apresentados os principais conceitos e aspectos referentes a Sistema de Proteção, principalmente no que se refere à segurança dos reatores nucleares de pesquisa. Sendo exposto alguns termos utilizados na área de aplicação. O sistema proposto nesta dissertação foi modelado através da linguagem de descrição de hardware VHDL (Very Speed Integrated Circuit), sendo utilizado o software ModelSim da Altera Software na programação das lógicas de desligamento automático (TRIP) do reator de pesquisa e na simulação de hipóteses de acionamento das mesmas. Os resultados deste estudo apontam que para toda a aplicação de software em reatores nucleares como ferramenta de auxílio na segurança dos mesmos, passe por um teste de verificação e validação, de forma a se adequar a norma IEC 60880.
Este trabalho revela-se de grande importância, considerando-se que os sistemas de proteção de um reator nuclear constitui como um elemento básico na segurança dos mesmos
Determinação de salinidade em meio aquoso empregando radiação gama para predição de frações de volume
Get PDFIn the offshore extraction, the produced water can present geometric characteristics that correspond to the mixture of forming water and the sea water (injection water) and the physical-chemical behavior of the injected water to allow the considerable variation of the salinity index Altering the water / oil ratio and making it difficult to predict mass balance calculations due to the large anisotropy of the reservoirs. One of the methods to evaluate the behavior of the injection water is to determine the salinity index (chlorides) of the water produced in each well. The fluids derived from this extraction are separated into their different fractions: liquid (hydrocarbons and organic compounds and water) and gas (natural gas). A real-time monitoring of water quality (salinity index) is required for pre-editing volume fractions in multiphase regimes. Densitometry is a noninvasive technique indicated to measure the water salinity index and determine its unsigned interference recorded by a scintillator. However, this technique shows high dependence on the chemical composition of the aqueous phase, which considerably affect the interaction of low energy gamma radiation with saline water. This work presents a methodology with our principles of gamma ray attenuation, using Monte Carlo simulations to calculate an influence of salinity on measurements using aqueous medium. The detection system uses a NaI(Tl) detector and two gamma radiation sources (137Cs and 241Am) to calculate the transmitted beam to obtain the maxima attenuation coefficients in salt samples. The NaCl, KCl and MgCl2 salts were investigated by varying the concentration percentage by 2%, 6%, 10% and 14%, in the energy range of 20 to 800 keV. Experimental validation uses a sample of sodium chloride (concentrations of 2.5, 2.0, 1.5 and 1.0 molar) using the known radioisotope values with 59.54 keV (241Am); 356.02 keV (133Ba); 662 keV (137Cs); 1.27 MeV (22Na) and 1.33 MeV (60Co). The MCNP-X computational code was used to develop an appropriate geometry to be implemented experimentally. The results obtained in the simulation were experimentally validated and the theoretical values of NIST and XCOM were compared with good agreement. The results indicate that the methodology for the correction of salinity index in calculations of volume fractions or to differentiate one from the production of injection water in low energy sources.Na extração offshore, a água produzida pode apresentar características geoquímicas que correspondem à mistura de água de formação (água conata) e da água do mar (água de injeção) e o comportamento físico-químico da água injetada permite variação considerável no índice de salinidade alterando a relação água/óleo e tornando-se difícil prever por cálculos do balanço de massa devido à grande anisotropia dos reservatórios. Um dos métodos para se avaliar o comportamento da água de injeção é determinar o índice de salinidade (cloretos) da água produzida em cada poço. Os fluidos oriundos desta extração são separados nas suas diferentes frações: líquida (hidrocarbonetos e compostos orgânicos e água) e gasosa (gás natural). Para a predição das frações de volume em regimes multifásicos torna-se necessário um monitoramento em tempo real da qualidade da água (índice de salinidade). A densitometria gama é uma técnica não invasiva indicada para medir o índice de salinidade da água e determinar sua interferência no sinal registrado por um detector cintilador. No entanto, essa técnica mostra alta dependência na composição química da fase aquosa, o que afeta consideravelmente a interação da radiação gama de baixa energia com a água salinizada. Este trabalho apresenta uma metodologia baseada nos princípios de atenuação de raios gama, por meio de simulações de Monte Carlo para calcular a influência da salinidade em medidas utilizando meios aquosos. O sistema de detecção utiliza um detector NaI(Tl) e duas fontes de radiação gama (137Cs e 241Am) para calcular o feixe transmitido visando obter os coeficientes de atenuação mássico em amostras salinas. Os sais NaCl, KCl e MgCl2 foram investigados variando o percentual de concentração em 2%, 6%, 10% e 14%, na faixa de energia de 20 a 800 keV. A validação experimental utilizou a amostra de cloreto de sódio (concentrações de 2,5; 2,0; 1,5 e 1,0 Molar) utilizando os valores de radioisótopos conhecidos, com 59,54 keV (241Am); 356,02 keV (133Ba); 662 keV (137Cs); 1,27 MeV (22Na) e 1,33 MeV (60Co). O código computacional MCNP-X foi utilizado para desenvolver a geometria apropriada a ser implementada experimentalmente. Os resultados obtidos na simulação foram validados experimentalmente e comparados valores teóricos do NIST e XCOM apontando boa concordância. Os resultados indicam que é possível utilizar esta metodologia para correção do índice de salinidade em cálculos de frações de volume ou ainda para diferenciar a água de produção da água de injeção utilizando fontes de baixa energia
Designing for Risk Assessment Systems for Patient Triage in Primary Health Care:A Literature Review
Get PDFBackground: This literature review covers original journal papers published between 2011 and 2015. These papers review the current status of research on the application of human factors and ergonomics in risk assessment systems’ design to cope with the complexity, singularity, and danger in patient triage in primary health care.
Objective: This paper presents a systematic literature review that aims to identify, analyze, and interpret the application of available evidence from human factors and ergonomics to the design of tools, devices, and work processes to support risk assessment in the context of health care.
Methods: Electronic search was performed on 7 bibliographic databases of health sciences, engineering, and computer sciences disciplines. The quality and suitability of primary studies were evaluated, and selected papers were classified according to 4 classes of outcomes.
Results: A total of 1845 papers were retrieved by the initial search, culminating in 16 selected for data extraction after the application of inclusion and exclusion criteria and quality and suitability evaluation.
Conclusions: Results point out that the study of the implications of the lack of understanding about real work performance in designing for risk assessment in health care is very specific, little explored, and mostly focused on the development of tool
20140326145316
No full textGeneral simulated scenes
These scenes followed a pre-defined script (see the Thesis for details), with common movements corresponding to general experiments. People go to or stand still in front of "J9", and/or go to the side of Argonauta reactor and come back again.
The first type of movement is common during Irradiation experiments, where a material sample is put within the "J9" channel; and also during neutrongraphy or gammagraphy experiments, where a sample is placed in front of "J9". Here, the detailed movements of putting samples on these places were not reproduced in details, but only the whole bodies' movements were simulated (as crouching or being still in front of "J9").
The second type of movement may occur when operators go to the side of Argonauta to verify some operational condition.
- Scene 1 (Obs.: Scene 1 of the "General simulated scenes" class):
Comprises one of the scenes with two persons. Both of them use clothes of light colors. Both persons remain still in front of "J9"; one goes to the computer and then come back, and both go out.
Video file labels: "20140326145316_IPCAM": recorded by the left camera.Comprises one of the scenes with two persons. Both of them use clothes of light colors. Both persons remain still in front of "J9"; one goes to the computer and then come back, and both go out
Solution of the Spatial Kinetic Equations Using the Expansion in Pseudo-Harmonics
Get PDFRecently was demonstrated that the steady-state fixed source problems, usually represented by a non homogeneous linear system of equations, can be solved by the method of the pseudoharmonics. The method of the pseudo-harmonics is based on the eigenfunctions associated with the leakage and removal matrix operator of the neutron diffusion equation. In this case the fixed source problem was solved considering that the neutron flux can be expanded in these eigenfunctions. The method of the pseudo-harmonics was just summarized in the determination of the coefficients of the expansion of the neutron flux, substituting like this an scheme of numeric inversion of the matrix of the linear system, usually employee in this problem type. The present work has as objective of study the possibility of to apply the method of the pseudoharmonic in the solution of the linear system, which appears starting from the discretization of the equations of the spatial kinetic. For so much the same basic idea used in the solution of the fixed source problem was adopted now for the spatial kinetic. The method was tested for the cases 1D, two groups of energy and six groups of precursors of delayed neutrons, formulated to leave of the discretization in finite differences of the kinetic
spatial equations. The method showed good results when compared with the direct method
Argonauta Video Database: Projection and Homography matrices. Homography Left Camera
No full textDescription of the Annotation files:
Annotation files are supplied for each video, for benchmarking. Annotations correspond to ground truths of peoples' positions in the image plane, and also for their feet positions, when they were visible.
Annotations were performed manually, with the aid of a code developed by (Silva et al., 2014; see the Thesis for details). Targets (people or feet) are marked at variable frame intervals and then linearly interpolated
A niching genetic algorithm applied to a nuclear power plant auxiliary feedwater system surveillance tests policy optimization
Get PDFThis article extends previous efforts on genetic algorithms (GAs) applied to a nuclear power plant (NPP) auxiliary feedwater system (AFWS) surveillance tests policy optimization. We introduce the application of a niching genetic algorithm (NGA) to this problem and compare its performance to previous results. The NGA maintains a populational diversity during the search process, thus promoting a greater exploration of the search space. The optimization problem consists in maximizing the system’s average availability for a given
period of time, considering realistic features such as: (i) aging effects on standby components during the tests; (ii) revealing failures in the tests implies on corrective maintenance, increasing outage times; (iii) components have distinct test parameters (outage time, aging factors, etc.) and (iv) tests are not necessarily periodic. We find that the NGA performs better than the conventional GA and the island GA due to a greater exploration of the search space
"20140327180750_IPCAM"
No full textScenes for Spectrography experiment
Scenes were recorded following the tasks involved in spectrography experiments, which are carried out in front of "J9" output radiadion channel, the latter in open condition. These tasks may be executed by one or two persons. One person can do the tasks, but requiring him to crouch in front of "J9" to adjust the angular position the experimental appartus (a crystal to bend the neutron radiation to the spectograph), and then to get up to verify data in a computer aside; these movements are repeated until achieving the right operational conditions. Two people may aid one another in such a way one remais crouched while the other remains still in front of the computer. They may also interchange tasks so as to divide received doses.
Up to now, there are available two scenes with one person and one scene with two persons. These scenes are described in the sequel:
- Scene 2:
Another take similat to Scene 1.
Video file labels: "20140327180750_IPCAM": recorded by the left camera.Comprises one of the scenes with one person performing spectography experiment