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Realidade virtual aplicada na avaliação ergonômica de salas de controle de plantas nucleares
No full textUma sala de controle de uma planta nuclear de potência é um sistema complexo, que
controla um processo nuclear e termodinâmico usado para produzir energia elétrica. Os
operadores interagem com sistemas representados através de interfaces gráficas e painéis, que
apresentam implicações significativas para a segurança da planta nuclear e influenciam a
atividade dos operadores. A realidade da atividade dos operadores em salas de controle exibe uma série de mecanismos ausentes das normas e guias nucleares de fatores humanos, importante para o processo de modernização e avaliação das salas de controle. A abordagem ergonômica considera as estratégias de operação, a interação entre os operadores, a interação
operador-sistema, e a interação entre os operadores e os grupos de apoio. O principal objetivo deste trabalho é apresentar a modelagem de uma sala de controle de uma planta nuclear, com o auxílio de um núcleo de jogo. Esta ferramenta será usada na avaliação dos aspectos ergonômicos da sala de controle, gerando informações e dados que possibilitarão a adequação das salas de controle às exigências legais do órgão regulador, auxiliando no licenciamento
nuclear.A nuclear power plant control room is a complex system that controls a nuclear and
thermodynamic process used to produce electrical energy. The operators interact with the
control room through interfaces that have significant implications to nuclear power plant safety
and influence the operator activity. The operator activity presents complexity features and
shows a series of mechanisms absents from the human factors guidelines, important to the
evaluation and update of control rooms. The ergonomics approach considers the operation
strategies, the interaction between the operators, the operator-system interaction, and
interaction between operators and support groups. The main objective of this paper is propose
the modeling of a nuclear control room, with the support of a game engine core. This tool will
be used in the ergonomic evaluation of nuclear control room, generating information and data
that will make possible the adequacy of control rooms features to the legal requirements of the
regulating agency, assisting the nuclear licensing
Validation of a NaI(Tl) detector’s model developed with MCNP-X code
No full textThe Monte Carlo method was used to calculate the photon detection efficiency and energy resolution
curves for a 1.500 100 NaI(Tl) scintillator detector (crystal þ housing þ photomultiplier tube material
equivalent) exposed to gamma rays in the energy range from 20 keV to 662 keV. This work aims to
design a precise computational model, based in Monte Carlo simulation, which can be used in practical
application. The energy resolution curve was used to improve the response of the mathematical simulation
of the detector. The detector was modeled with the MCNP-X code and the results were compared
to experimental photopeak efficiency measurements of radiation sources. The results showed good
agreement with the experimental data.The Monte Carlo method was used to calculate the photon detection efficiency and energy resolution
curves for a 1.500 100 NaI(Tl) scintillator detector (crystal þ housing þ photomultiplier tube material
equivalent) exposed to gamma rays in the energy range from 20 keV to 662 keV. This work aims to
design a precise computational model, based in Monte Carlo simulation, which can be used in practical
application. The energy resolution curve was used to improve the response of the mathematical simulation
of the detector. The detector was modeled with the MCNP-X code and the results were compared
to experimental photopeak efficiency measurements of radiation sources. The results showed good
agreement with the experimental data
Development of nanoradiopharmaceuticals by labeling polymer nanoparticles with Tc‑99m
No full text3 p.Nanomedicine is considered as the future of modern medicine. Hence, serious global efforts are being made for the developmentof nanopharmaceuticals. Among all the nanopharmaceuticals developed so far, radiopharmaceuticals constitute only a very smallportion, as noted in the published literature. The procedures for development of nanoradiopharmaceuticals are complex. In thispaper we discuss the results of a research directed at developing nanoradiopharmaceuticals based on three different types ofnanopharmaceuticals as alternative drug delivery systems
Ergonomic work analysis in radiopharmaceuticals production
No full textOs radiofármacos são elementos radioativos utilizados no diagnóstico e tratamento em Medicina Nuclear. O objetivo deste estudo foi identificar os riscos ergonômicos envolvidos nas atividades de empregados de um instituto de pesquisa do governo brasileiro, localizado no Rio de Janeiro, durante a expedição de radiofármacos produzidos.Radiopharmaceuticals are radioactive elements used in the diagnosis and treatment in Nuclear Medicine. The aim of this study was to identify ergonomic risks involved in the activities of employees of a Research Institute of the Brazilian Government, located at Rio de Janeiro, during the dispatch of produced radiopharmaceuticals
Hardware Reconfigurável para Classificação de Elementos Radioativos Utilizando o Método de Agrupamento Subtrativo.
Get PDFRadioactivity is the spontaneous emission of energy from unstable atoms. Radioactive sources have radionuclides.
Radioactive sources undergoes radioactive decay and emits gamma rays and subatomic particles, constituting the ionizing radiation.
The gamma ray energy of a radionuclide is used to determine the identity of gamma emitters present in the source. This paper
describes the hardware implementation of subtractive clustering algorithm to perform radionuclide classification in order to identify
them.A radioatividade é a emissão espontânea de energia a partir de átomos instáveis. Fontes radioativas possuem radionuclídeos,
os elementos radioativos. Radionuclídeos sofrem decaimento e emitem raios gama e partículas, constituindo a radiação
ionizante. A energia de raios gama de um radionuclídeo é usada para determinar a identidade de emissores gama presentes na
fonte. Este artigo descreve a implementação em hardware do algoritmo de agrupamento subtrativo para executar a classificação de
elementos radioativos, visando a sua identificação
Are radiopharmaceuticals safe? the case of FDG-18
Get PDF5 p.Too many false-positive and adverse reactions related to radiopharmaceuticals take place every day in hospitals routine, but many are not reported or even sensed. Information concerning these kind of reactions is not abundant and nuclear medicine staff is usually overwhelmed by this information. As every healthcare intervention carries some risk of harm, clinical decision making needs to be supported by a systematic assessment of the balance of benefit to harm. A systematic review that considers only the favorable outcomes of an intervention, without also assessing the adverse effects and false positives reactions, can mislead by introducing a bias favoring the intervention that in the case o radiopharmaceuticals may to render a important factor related not even to the quality of the drug but even to the quality of the diagnosis. The results suggest a logical framework to make decisions in reviews that incorporate false positive and adverse reactions. Also, was explored situations where a comprehensive investigation of false positive reactions and adverse effects was warranted and suggest strategies to identify practicable and clinically useful outcomes. We concluded that there is the necessity to include and to recognize how strategic choices made in the review process determine what harms are found, and how the findings may affect clinical decisions. Researchers undertaking a systematic review that incorporates false positive reaction and adverse reactions must understand the rationale for the suggested methods and be able to implement them in their review. Beyond a world effort should be made to report as many cases of false positive and adverse reactions with radiopharmaceuticals as possible. Only if this is done a complete picture of false positive reactions with radiopharmaceuticals can be drawn
Hardware reconfigurável para identificação de radionuclídeos utilizando método de agrupamento subtrativo
Get PDFRadioactive sources include radionuclides. A radionuclide is an atom with an unstable nucleus,
i.e. a nucleus characterized by excess of energy, which is available to be imparted. In this process, the radionuclide undergoes radioactive decay and emits gamma rays and subatomic particles, constituting the ionizing radiation. So, radioactivity is the spontaneous emission of energy from unstable atoms. Correct radionuclide identification can be crucial to planning protective measures, especially in emergency situations, by defining the type of radiation source and its radiological hazard. This project introduces the application of subtractive clustering method, in a hardware implementation, for an identification system of radioactive elements that allows a rapid and efficient identification. In software implementations, clustering algorithms, usually, are demanding in terms of processing time. Thus, a custom implementation on reconfigurable hardware is a viable choice in embedded systems, so as to achieve real-time execution as well as low power consumption. The proposed architecture for the hardware of subtractive clustering is scalable, allowing for the inclusion of more of subtractive clustering unit that operate in parallel. This provides greater flexibility to accelerate the hardware with respect to the time and area requirements. The results show that the expected cluster center can be identified with efficiently. The identification of these points can classify the radioactive
elements present in a sample. Using the designed hardware, it is possible to identify more than one cluster center, which would lead to the recognition of more than one radionuclide in radioactive sources. These results reveal that the proposed hardware to subtractive cluster can be used to design a portable system for radionuclides identification.Fontes radioativas possuem radionuclídeos. Um radionuclídeo é um átomo com um núcleo instável, ou seja, um núcleo caracterizado pelo excesso de energia que está disponível para ser emitida. Neste processo, o radionuclídeos sofre o decaimento radioativo e emite raios gama e partículas subatômicas, constituindo-se na radiação ionizante. Então, a radioatividade é a emissão espontânea de energia a partir de átomos instáveis. A identificação correta de radionuclídeos pode ser crucial para o planejamento de medidas de proteção, especialmente em situações de emergência, definindo o tipo de fonte de radiação e seu perigo radiológico. Esta dissertação apresenta a aplicação do m´método de agrupamento subtrativo, implementada em hardware, para um sistema de identificação de elementos radioativos com uma resposta rápida e
eficiente. Quando implementados em software, os algoritmos de agrupamento consumem muito tempo de processamento. Assim, uma implementação dedicada para hardware configurável é uma boa opção em sistemas embarcados, que requerem execução em tempo real, bem como baixo consumo de energia. A arquitetura proposta para o hardware de cálculo do agrupamento subtrativo é escalável, permitindo a inclusão de mais unidades de agrupamento subtrativo para operarem em paralelo. Isso proporciona maior flexibilidade para acelerar o processo de acordo com as restrições de tempo e de área. Os resultados mostram que o centro do agrupamento pode ser identificado com uma boa eficiência. A identificação desses pontos pode classificar os elementos radioativos presentes em uma amostra. Utilizando este hardware foi possível identificar mais do que um centro de agrupamento, o que permite reconhecer mais de um
radionuclídeos em fontes radioativas. Estes resultados revelam que o hardware proposto pode ser usado para desenvolver um sistema portátil para identificação radionuclídeos