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Evaluation of 3 dimensional video to dissemination of nuclear energy by high school students
Get PDFEducational videos can enhance the information transmission, making it more didactic. The use of virtual reality technologies can turn the environment even more entertaining through 3D projections, due to its imersive characteristics. Using these technologies can improve learning, since they provide more ludic means, as compared to traditional ones, such as texts, oral presentations and static images. This paper encompass the development of an educational video and an assessment carried out with students through a questionnaire. Students’ assessment is in agreement with this work’s objectives. They found the activity fun, enjoyable, and the use of 3D video drew students' attention to important details of the contents, such as power generation; the way nuclear power plants are distributed to cities; their distribution in the world including Brazil; that nuclear power is safe, economical and efficient; the understanding of nuclear energy as a clean and harmless power source; in addition to applications in medicine
Mobility of radionuclides and rare earth elements in the coastal area of Rio de Janeiro: implications for monazite deposits in offshore areas
Get PDF24 p., il.Analysis of ground and airborne radiometric data as well as rare earth element abundances in soils in the Saquarema region (Rio de Janeiro, Brazil) has allowed new insights into the mobility of mineral aggregates containing monazites. The regional distributions of radioactive elements, as revealed in results of airborne radiometric surveys, indicate that topography play dominant role in transportation of weathered material. The mobility pattern is characterized by systematic depletion of radioactive elements along the migration paths. Superimposed on this depletion trend are indications of relative enrichment of uranium and thorium with respect to potassium along the migration paths. Analysis of data on rare earth element abundances in soils and beach sands point to the existence of a complementary process responsible for formation of ore-grade deposits of monazites along the coastal regions. The time and distance scales associated with this enrichment process have been estimated based on the regional distribution of Th/K ratios. The results indicate that submerged monazite deposits may be present along the offshore sand banks, in the coastal region of the state of Rio de Janeiro. These results may be useful in locating under-water monazite deposits in other parts of continental shelf with similar geologic context
A fuzzy logic based method to monitor organizational resilience: application in a brazilian radioactive facility
Get PDFResilience is the intrinsic ability of a system to adjust its functioning prior to, during, or following changes and
disturbances, so that it can sustain required operations under expected and unexpected conditions. This
definition focuses on the ability to function, rather than on being impervious to failure, and thereby overcomes
the traditional conflict between productivity and safety. Resilience engineering (RE) has fast become ecognized
as a valuable complement to the established approaches to safety of complex socio-technical systems and
methods to monitor organizational resilience are needed. However, few, if any, comprehensive and systematic
research studies focus on developing an objective, reliable and practical assessment model for monitoring
organizational resilience. Most methods cannot fully solve the subjectivity of resilience evaluation. In order to
remedy this deficiency, the aim of this research is to adopt a Fuzzy Set Theory (FST) approach to establish a
method for resilience assessment in organizations based on leading safety performance indicators, defined
according to the resilience engineering principles. The method uses FST concepts and properties to model the
indicators and to assess the results of their application. To exemplify the method we performed an exploratory
case study at the process of radiopharmaceuticals dispatch package of a Brazilian radioactive facility
Reactor kinetic formulation using the finite element method
Get PDFThis research has the objective of solving the spatial Kinetic equations for two energy groups using the finite element method. In the methodology, was applied the direct method, such that matrix equations coefficients from spatial discretization was generated by finite element method. The formulation of the time-dependent problem was obtained by analytical integration of precursor concentration equation and using the Euler implicit scheme in the dynamic diffusion problem. A 2D example of a reactor static diffusion problem was solved using a linear triangular finite element. This solution was compared with the numerical benchmark solution, found in the literature, and the numerical results calculated by the finite difference methods. This comparison shows the capacity of the finite element method to obtain a precise solution
Computer codes for the calculation of thermodynamic properties of water
Get PDFLinear interpolation algorithms are commonly used for the calculation of the thermodynamic properties of water
in thermal-hydraulic analysis systems. However, these algorithms can use a substantial amount of computation
time. An alternative for this approach is to use approximation formulas. On the other hand, the steam tables are
created from empirical data, which can be represented by a set of points in a graph of certain property. There is
no function that can integrally represent the curves formed by these points, some functions are adjusted to
represent satisfactorily certain range. Together they compose the curves that relate the properties. It aims to
introduce two computer codes (PARSTEAM and NBSNRCE) designed to perform the function of steam tables
printed, with the purpose of speeding up the process of analysis and as support for other computer codes; and
show that such codes have good accuracy, compared with steam tables
compartilhamento de serviços na Administração Pública Federal: análise dos fatores de aplicabilidade na Autarquia Federal
Get PDFThis study examines, among the factors that can facilitate or discourage the implementation of a model of the Shared Services Center (CSC) in federal agency CNEN / RJ, which would be more relevant and more weight in view of the area managers sharing proposal . As research questions was analyzed if the CSC model can be applied as a tool for organizational restructuring in the public area. Bibliometric survey was conducted on the subjects managerial public administration, organizational change and motivators of CSC. A questionnaire was adapted from a model tested on the subject, and applied together with area managers share object; finance, human resource, procurement and information technology. The data were processed through the standard scale liket and analyzed. The results indicate that the factors that favor the implementation of a model of the CSC CNEN / RJ are the most significant factors that disfavor the use of the model. Research indicates that, based on examples from other countries, the CSC model can contribute as a tool for organizational restructuring in response to drivers of change identified in the company, in order to react acertivamente.A presente pesquisa analisa, dentre os fatores que podem favorecer ou desfavorecer a implantação de um modelo de Centro de Serviços Compartilhados (CSC) na autarquia federal CNEN/RJ, quais seriam mais relevantes e de maior peso na visão dos gestores das áreas de compartilhamento proposta. Como questão da pesquisa foi analisado se o modelo de CSC pode ser aplicado como ferramenta de reestruturação organizacional na área pública. Foi realizado levantamento bibliométrico sobre os temas administração pública gerencial, motivadores da mudança organizacional e o CSC. Foi adaptado um questionário, a partir de um modelo testado sobre o tema, e aplicado juntos aos gestores das áreas objeto de compartilhamento; finanças, recurso humanos, suprimento e tecnologia de informação. Os dados foram tratados através dos padrões da escala Liket e analisados. Os resultados indicam que os fatores que favorecem a implantação de um modelo de CSC na CNEN/RJ são mais significativos que os fatores que desfavorecem o uso do modelo. A pesquisa indica que, fundamentado em exemplos de outros países, o modelo de CSC pode contribuir como ferramenta de reestruturação organizacional, em resposta aos motivadores de mudança identificados na empresa, a fim de reagir assertivamente
Avaliação de membranas de nanofiltração para o tratamento de rejeito radioativo líquido
No full textO comportamento físico-químico de duas membranas de nanofiltração foi
avaliado através de testes estáticos, dinâmicos e de concentração para o tratamento
de rejeito líquido radioativo (água carbonatada), produzido na reconversão do gás
hexafluoreto de urânio a dióxido de urânio no ciclo do combustível nuclear. Este
rejeito contém cerca de 7,0 mg L-1 de urânio e não pode ser eliminado para o meio
ambiente sem um tratamento adequado. Nos testes estáticos amostras de
membranas foram imersas no rejeito de 24 até 5000 h. As propriedades de
transporte (permeabilidade hidráulica, fluxo permeado, rejeição aos íons sulfato e
cloreto) foram avaliadas antes e após imersão no rejeito em sistema de permeação
de escoamento frontal a 5 bar. A camada superficial (poliamida) foi caracterizada por
potencial zeta, ângulo de contato, microscopia eletrônica de varredura por emissão
de campo, microscopia de força atômica, espectroscopia de infravermelho,
fluorescência de raios-x e análise termogravimétrica antes e após os testes
estáticos. No teste dinâmico o rejeito foi permeado a 5 bar e as membranas
apresentaram rejeição ao urânio acima de 85%. Testes de curta duração (24-72 h)
mostraram que a camada seletiva e a carga superficial das membranas não
apresentaram alterações químicas, segundo espectros de infravermelho. Entretanto,
após 5000 h as membranas apresentaram desprendimento de uma camada
superficial de PVA, poli(álcool vinílico). Após essa perda, as membranas
apresentaram menor rejeição para o urânio. Os testes de permeação e concentração
do rejeito foram realizados em sistema de permeação de escoamento tangencial a
15 bar. A rejeição a urânio foi ao redor de 90% para teste de permeação. Nos testes
de concentração o permeado foi coletado continuamente até redução do volume de
80% do volume de alimentação. A rejeição de urânio foi de 97%. As membranas de
nanofiltração testadas foram eficientes para concentrar o urânio do rejeito
Simulação de detecção de fotóns em sistemas espectrométrico de alta pureza (HPGe) usando o código MCNPX
No full textA Comissão Nacional de Energia Nuclear define parâmetros para a classificação e
gerenciamento de rejeitos radiativos de acordo com a atividade dos materiais. A
eficiência de um sistema de detecção é crucial para se determinar a real atividade
de uma fonte radiativa. Quando possível, a calibração do sistema deve ser realizada
por meio de uma fonte padrão. Infelizmente, apenas em poucos casos a calibração
pode ser feita desta forma, dada a dificuldade de se obter a fonte padrão apropriada
para cada tipo de medição. Assim, simulações computacionais podem ser realizadas
para auxiliar no cálculo da eficiência do sistema e, por conseqüência, auxiliar
também na classificação de rejeitos. Este trabalho tem por objetivo modelar um
detector de germânio de alta pureza com o código MCNPX, aproximando, mediante
alterações na camada morta externa do cristal de germânio do detector modelado,
os valores espectrais obtidos computacionalmente dos valores obtidos
experimentalmente para o fotopico do 137Cs.The National Commission of Nuclear Energy defines parameters for classification
and management of radioactive waste in accordance with the activity of materials.
The efficiency of a detection system is crucial to determine the real activity of a
radioactive source. When it’s possible, the system’s calibration should be performed
using a standard source. Unfortunately, there are only a few cases that it can be
done this way, considering the difficulty of obtaining appropriate standard sources for
each type of measurement. So, computer simulations can be performed to assist in
calculating of the efficiency of the system and, consequently, also auxiliary the
classification of radioactive waste. This study aims to model a high purity germanium
(HPGe) detector with MCNPX code, approaching the spectral values
computationally obtained of the values experimentally obtained for the photopeak of
137Cs. The approach will be made through changes in outer dead layer of the
germanium crystal modeled