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Real time determination of dose radiation through artificial intelligence and virtual reality
Get PDFIn the last years, a virtual environment of Argonauta research reactor, sited in the Instituto de Engenharia
Nuclear (Brazil), has been developed. Such environment, called here Argonauta Virtual (AV), is a 3D model of
the reactor hall, in which virtual people (avatar) can navigate. In AV, simulations of nuclear sources and doses
are possible. In a recent work, a real time monitoring system (RTMS) was developed to provide (by means of
Ethernet TCP/IP) the information of area detectors situated in the reactor hall. Extending the scope of AV, this work is intended to provide a continuous determination of gamma radiation dose in the reactor hall, based in several monitored parameters. To accomplish that a module based in artificial neural network (ANN) was developed. The ANN module is able to predict gamma radiation doses using as inputs: i) the avatar position (from virtual environment), ii) the reactor power (from RTMS) and iii) information of fixed area detectors (from RTMS). The ANN training data has been obtained by measurements of gamma radiation doses in a mesh of points, with previously defined positions, for different power levels. Through the use of ANN it is possible to estimate, in real time, the dose received by a person at any position in Argonauta reactor hall. Such approach allows tasks simulations and training of people inside the AV system, without exposing them to radiation effects
Cold neutron irradiation facility for the brazilian research reactors
Get PDFNeutron irradiation in research reactors and accelerators can be realized at appropriated neutron guides or beam
holes shared around a cold neutron source (CNS) with neutron of variable intensity and energy. An irradiation
facility for multiple applications including an intense CNS was calculated for the three Brazilian research
reactors and can be utilized as a first concept for the new research reactor to be designed, the Brazilian multiple
purpose research reactor (RMB). A study about coolant and moderators properties, and simulations with neutron
physics and thermal codes, may be important for the definition of the type of the CNS to be utilized. Some
earlier results of MCNP simulations and a discussion about the different factors involved in the definition of its
installation in the Brazilian research reactors are here presented. One suggests an international cooperation for
the design development of this system and posterior construction of a prototype in the Argonauta reactor at the
Instituto de Engenharia Nuclear (IEN-CNEN-RJ). It is also being considered the inclusion of other devices as a
neutron fiber to guide the neutron beams away of the gamma radiation and fast neutron background. The cold
neutron facility increases the intensity of cold neutrons, without the need of additional fuel burn up
Evaluation of Gaseous Fluid Dispersion Through Packed Bed Using Radiotracers Technique
Get PDFIn this study, it was developed a methodology for the determination of the dispersion of a gaseous tracer
in porous media using the radiotracer technique. In order to evaluate several porous media, a cylindrical
filter was constructed in PVC and connected to a system with constant flow. Inside this unit silica crystals
(16-20) mesh was used as porous media and CH3Br (Methyl Bromide) marked with 82Br was used as
radiotracer. An instantaneous pulse of tracer was applied in the system entrance and registered by two
NaI (3x3)” scintillation detectors located one before and the other after the filter. The curves produced by
the radioactive cloud and recorded by the detector were analyzed statistically using the weighted moment
method. The mathematical model one considered as great dispersion of tracer was used to evaluate the
flow conditions inside the filter system. The results show us that the weight moment method associated
with radiotracer techniques is useful to evaluated an industrial filter and allows to measure the residence
time distribution, τ, and the axial dispersion, DAB, gas in a porous medium
Propagation speed of y-radiation in brass
No full textThe propagation speed (PS) of visible light -represented by a short frequency range in the large frame of electromagnetic radiations (ER) frequencies- in air was measurecL during the last centuryl li, using a great deal of different methods, with high precision results being achieved. Presently, a well accepted value, with very small uncertainty, is c= 299,792.458 Km/síCJ (c reporting to the Latin word celeritas: "speed swiftness·'). \Vhen propagating in denser material media (MM), such value is always lower when compared to the air value, with the propagating MM density playing an important role. Until present, such studies focusing propagation speeds, refractive indexes, dicspersions were specially related to visible light, or to ER in wavelengths ranges dose to it, and with a transparent MM. A first incursion in this subject dealing \\~th y-rays was performed using an electronic coincidence c01.mting system, when the vaIue of it's PS was measured in air, Cf(air)= 298,300.15 Km/s(3l ; a method that went on with later electronic improvements. always in air. To perfonn such measurements the avaiIability of a y-radiation source in which two y-rays are emitted simultaneousIy in opposite directions -as already used(4.5) as welI as applied in the present case- turns out to be essential to the feasibility of the experiment, as far as no reflection techniques could be used. Such a suitable source was the positron emitter cCNa placed in a thin walI metal container in which the positrons are stopped and annihilated when reacting \\1th the medium electrons, in such way originating -as it is very welI established from momentlill1/energy conservation laws(6J- 1:\\70 y-rays, energy 511 KeV each. both emitted simultaneously in opposite directions. In alI the previous experiments were used photomultiplier detectors
coupled to NaI(Tl) crystal scintillators, which have a good energy resolution but a deficient time resolution
for such purposes. Presently, as an innovative improvement, were used BaF2 and CsF crystal scintilIators
which display a much better time resolution. IncidentalIy, the use of y-rays would a110w a detennination of
ER propagation values in non-transparent MM, nontransparent for visible light; and in such a way better
sketching their structural -or of other nature- properties that may interfere \\'Íth this propagation
A gestão do conhecimento com base em mapa conceitual para a construção do conhecimento coletivo na área nuclear
Get PDFThis dissertation´s proposition is to design and build a tool to aid the knowledge management based in the intellectual capital as a value and competitiveness aggregator for a science, technology and innovation public organization in the Brazilian’s nuclear area.
It will be presented the hole survey of the finalistic activities and what has been considered the intellectual capital to be developed and strategically valuated in its decision making practices.
It was also surveyed the inter relations between the stakeholders, hereby the maintainer (CNEN), federal government, support foundations, public employees and contributors, in many different aspects focusing the continuity of research and development (R&D) activities and its results.
As it’s going to be later detailed, the tool has been designed based in the concept map methodology using the Cmap tools software. The hole cognitive basis used here was constructed under disclosed and recognized knowledge models about knowledge, knowledge management, knowledge transference and intellectual capital.
A plenty of recommendations for the internal processes improvement, of the chosen institution, are presented in this dissertations’ end, basing in the visibility obtained by the concept maps application.CNEN1 APRESENTAÇÃO 1
1.1 INTRODUÇÃO 1
1.2 OBJETIVO 1
1.3 JUSTIFICATIVA E RELEVÂNCIA 2
1.4 ORGANIZAÇÃO DA TESE 2
2 FUNDAMENTAÇÃO TEÓRICA 3
2.1 NA SOCIEDADE DO CONHECIMENTO 3
2.1.1 Trabalhadores do conhecimento 3
2.1.2 Conhecimento 4
2.2 TRANSFERÊNCIA DE CONHECIMENTO 4
2.3 GESTÃO DO CONHECIMENTO 6
2.4 CAPITAL INTELECTUAL 8
3 MAPAS CONCEITUAIS 11
4 MOTIVAÇÃO PARA CONSTRUÇÃO DA FERRAMENTA 14
4.1 ORGANIZAÇÃO ESCOLHIDA 15
4.2 SOFTWARE ESCOLHIDO – CMAP – CONCEPT MAP 16
5 METODOLOGIA PARA MODELAGEM 19
5.1. CENTROS DE CONHECIMENTO 20
5.2. ÁREAS DE INTEGRAÇÃO SISTÊMICA 20
5.3. ÁREAS DE ATUAÇÃO 21
5.4. PROCESSOS 21
5.5. EQUIPES DE PROCESSO 22
5.6. PRODUÇÃO CIENTÍFICA 29
6 CONSTRUÇÃO DA FERRAMENTA 35
7 LEVANTAMENTO DE DADOS E CONSTRUÇÃO DOS MAPAS 39
8 RESULTADOS 46
9 DISCUSSÃO E CONSIDERAÇÕES FINAIS 61
ANEXO A 73
ANEXO B 88A proposta desta dissertação é a modelagem e construção de uma ferramenta para auxiliar a gestão do conhecimento tendo por base o entendimento do capital intelectual como agregador de valor e competitividade para uma organização de CT&I pública na área nuclear brasileira.
Será apresentado todo o levantamento referente às atividades consideradas finalísticas pela instituição e o que foi considerado o capital intelectual a ser desenvolvido e estrategicamente avaliado e tratado em suas tomadas de decisão. Também foi levantado suas inter-relações com as chamadas partes interessadas, aqui tratando-se da mantenedora (CNEN), governo federal, fundações de apoio, servidores e colaboradores no que se referia aos diversos desdobramentos para garantia da continuidade das atividades de pesquisa e desenvolvimento (P&D) e apresentação de resultados.
Como será visto em detalhes, a ferramenta foi modelada tendo por base a metodologia de mapas conceituais com o auxílio do software Cmap Tools. Toda a base cognitiva empregada utilizou modelos de entendimento propagados e reconhecidos sobre conhecimento, gestão do conhecimento, transferência de conhecimento e capital intelectual.
Uma série de recomendações para a melhoria do desenvolvimento dos processos internos da instituição, escolhida para estudo de caso, são apresentadas ao final do trabalho, com base na visibilidade obtida com a aplicação dos mapas conceituais
A computerized tool to evaluate the cognitive compatibility of the emergency operational procedures task flow.
No full textDeterminação de dose de radiação, em tempo real, através de inteligência artificial e realidade virtual
No full textNos últimos anos foram desenvolvidos trabalhos nos quais criou-se um
modelo virtual do reator de pesquisa Argonauta, localizado no instituto de
Engenharia Nuclear (Brasil), chamado Argonauta Virtual (AV). O AV é um
modelo tridimensional onde personagens virtuais (avatares) podem transitar e
interagir. Nele é possível fazer simulações de fontes nucleares e doses de
radiação. No trabalho mais recente, um sistema de monitoramento em tempo
real foi desenvolvido a fim de disponibilizar (através de Ethernet TCP/IP)
informações dos detectores de área situados no salão do reator.
Estendendo o uso do AV, esse trabalho tem por objetivo desenvolver um
sistema capaz de determinar a dose de radiação no interior do salão do reator
para uma dada posição, sob determinada condição operacional. Para tal, um
módulo baseado em redes neurais artificiais (RNA) foi desenvolvido e treinado a
partir de um conjunto de medidas realizadas no interior do salão do reator.
Usando como entrada: i) posição do avatar, ii) Potência do reator e iii) dados de
detectores fixados na instalação física, a RNA é capaz de predizer a dose de
radiação recebida. A função interpoladora, gerada a partir da RNA, foi inserida
nesse ambiente virtual, possibilitando assim a visualização do perfil das
radiações e com isso o treinamento de pessoas e funcionários sem expô-los
aos seus efeitos. Os resultados obtidos demonstraram o perfil contínuo da
radiação e sua inserção em ambiente virtual fazendo com que a medição da
dose absorvida pelo personagem se tornasse mais precisa em relação à sua
posição.In the last years, a virtual environment of Argonauta research reactor,
sited in the Instituto de Engenharia Nuclear (Brazil), has been developed. Such
environment, called here Argonauta Virtual (AV), is a 3D model of the reactor
hall, in which virtual people (avatar) can navigate. In AV, simulations of nuclear
sources and doses are possible. In a recent work, a real time monitoring system
(RTMS) was developed to provide (by means of Ethernet TCP/IP) the
information of area detectors situated in the reactor hall.
Extending the scope of AV, this work is intended to provide a continuous
determination of gamma radiation dose in the reactor hall, based in several
monitored parameters. To accomplish that a module based in artificial neural
network (ANN) was developed. The ANN module is able to predict gamma
radiation doses using as inputs: i) the avatar position (from virtual environment),
ii) the reactor power (from RTMS) and iii) information of fixed area detectors
(from RTMS).
The ANN training data has been obtained by measurements of gamma
radiation doses in a mesh of points, with previously defined positions, for
different power levels.
Through the use of ANN it is possible to estimate, in real time, the dose
received by a person at any position in Argonauta reactor hall. Such approach
allows tasks simulations and training of people inside the AV system, without
exposing them to radiation effects
An experimental study on the application of single-phase ultrasonic flowmeter in the stratified horizontal two-phase flow.
No full textEste artigo descreve um trabalho experimental realizado com o objetivo de investigar uma técnica de ultra-som híbrido
aptidão para a medição de um fluxo de gás-líquido estratificado de duas fases nos tubos horizontais. As experiências envolvem a utilização de
uma técnica de eco único pulso e um transdutor contrapropagating industrial clamp-on ultrassônico para
líquidos. A técnica de eco único impulso de transdutor consiste na instalação de um único transdutor de ultra-sons na parte inferior
um tubo horizontal, onde um gás-liquido de duas fases é estratificada fluxo ocorrendo. Uma parte do pulso ultra-sônico descarregada
desde o transdutor será transmitida através do líquido e depois reflectida para trás a partir da interface gás-líquido. por
medir o tempo de trânsito das reflexões é possível determinar o nível de líquido. Para um medidor ultra-sônico
sinal de ultra-som, que vem de um primeiro transdutor ultra-sônico colocado a montante do lado de fora da parede do tubo, e viajar
inteiramente através da fase líquida do fluxo estratificado de duas fases com um ângulo de inclinação em relação à secção transversal
do tubo, é reflectida pela interface entre o líquido e gás. Após esta reflexão que se segue a uma segunda ultra-sônico
transdutor para jusante para o mesmo lado do primeiro. Em seguida, a velocidade do líquido é feita a média ao longo deste caminho pela
medidor de vazão ultra-sônico. Para converter esta velocidade em uma velocidade média ao longo da secção transversal ocupada por líquido, um
factor de correcção é necessário. Com base nesta configuração, um modelo físico-matemático com base no Reynolds
Média de Navier-Stokes é usado para obter o campo de velocidades completa do fluxo. Assim, o componente de velocidade em qualquer
caminho de ultra-sons, detectada pelo medidor de fluxo ultra-sónica, podem ser determinadas numericamente bem como o nível do líquido. a partir de
Neste procedimento, um factor de correcção emerge como uma relação entre a velocidade média de uma secção transversal arbitrária
ocupada pelo líquido, e a velocidade média ao longo do percurso de ultra-sons. Os resultados experimentais são comparados
com os cálculos numéricos, a fim de verificar a técnica de ultra-som híbrido empregado e seu potencial como um útil
dispositivo para medir as de duas fases gás-líquido fluxos estratificados.This paper describes an experimental work conducted in order to investigate a hybrid ultrasonic technique
suitability for measuring a two-phase gas-liquid stratified flow in horizontal pipes. The experiments involve the use of
a single transducer pulse echo technique and an industrial contrapropagating clamp-on ultrasonic flowmeter for
liquids. The single transducer pulse echo technique consists in installing a single ultrasonic transducer at the bottom of
a horizontal pipe, where a two-phase gas-liquid stratified flow is ocurring. One part of the ultrasonic pulse discharged
from the transducer will be transmitted through the liquid and then reflected back from the liquid-gas interface. By
measuring the transit time of the reflections it is possible to determine the liquid level. For the ultrasonic flowmeter an
ultrasonic signal, coming from a first ultrasonic transducer placed upstream outside the pipe wall, and travelling
wholly through the liquid phase of the two-phase stratified flow with an inclination angle relative to the cross section
of the pipe, is reflected by the interface between the liquid and gas. After this reflection it follows to a second ultrasonic
transducer downstream at the same side of the first one. Then, the liquid velocity is averaged along this path by the
ultrasonic flowmeter. To convert this velocity in a velocity averaged along the cross section occupied by the liquid, a
correction factor is required. Based on this configuration, a physical-mathematical model based on the Reynolds
Averaged Navier-Stokes is used to obtain the complete velocity field in the flow. Thus, the velocity component in any
ultrasonic path, detected by the ultrasonic flowmeter, can be determined numerically as well as the liquid level. From
this procedure, a correction factor emerges as a relation between the averaged velocity in an arbitrary cross section
occupied by the liquid, and the averaged velocity along the ultrasonic path. The experimental results are compared
with the numerical calculations in order to check the hybrid ultrasonic technique employed and its potential as a useful
device for measuring the two-phase gas-liquid stratified flows
Parallel particle swarm optimization algoritms in nuclear problems
Get PDFParticle Swarm Optimization (PSO) is a population-based metaheuristic (PBM), in which solution candidates evolve through simulation of a simplified social adaptation model. Putting together robustness, efficiency and simplicity, PSO has gained great popularity. Many successful applications of PSO are reported, in which PSO demonstrated to have advantages over other well-established PBM. However, computational costs are still a great constraint for PSO, as well as for all other PBMs, especially in optimization problems with time consuming objective functions. To overcome such difficulty, parallel computation has been used. The default advantage of parallel PSO (PPSO) is the reduction of computational time. Master-slave approaches, exploring this characteristic are the most investigated. However, much more should be expected. It is known that PSO may be improved by more elaborated neighborhood topologies. Hence, in this work, we develop several different PPSO algorithms exploring the advantages of enhanced neighborhood topologies implemented by communication strategies in multiprocessor architectures. The proposed PPSOs have been applied to two complex and time consuming nuclear engineering problems: i) reactor core design (CD) and ii) fuel reload (FR) optimization. After exhaustive experiments, it has been concluded that: i) PPSO still improves solutions after many thousands of iterations, making prohibitive the efficient use of serial (non-parallel) PSO in such kind of realworld problems and ii) PPSO with more elaborated communication strategies demonstrated to be more efficient and robust than the master-slave model. Advantages and peculiarities of each model are carefully discussed in this work
Realidade virtual para identificação de defeitos e fraturas em imagnes
Get PDFEste trabalho descreve o desenvolvimento de um sistema para análise não destrutiva de materiais através da
visualização tridimensional estéreo, com o emprego de técnicas de realidade virtual. Consiste num conjunto de
experimentos e técnicas computacionais envolvendo o uso de duas imagens, cada uma relativa à imagem vista por um olho, de forma a compor a imagem tridimensional. Com a visualização em três dimensões e a escala previamente definida, pode-se fazer uma análise e assim avaliar possíveis falhas no material em estudo