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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Desenvolvimento e aplicacao de um detector para a medida absoluta da taxa de fluencia de neutrons na regiao de MeV

DIAS, MAURO da S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:17Z (GMT). No. of bitstreams: 1 03269.pdf: 4525465 bytes, checksum: 8d08a1f89182180eaf465278796a6732 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
12

Monte Carlo modeling of the patient and treatment delivery complexities for high dose rate brachytherapy / Modelagem pelo método de Monte Carlo do paciente e das complexidades dos tratamentos braquiterápicos com alta taxa de dose

FONSECA, GABRIEL P. 10 December 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-12-10T16:54:22Z No. of bitstreams: 0 / Made available in DSpace on 2015-12-10T16:54:22Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tratamentos braquiterápicos são comumente realizados conforme o relatório da American Association of Physicists in Medicine (AAPM), Task Group report TG-43U1, o qual define o formalismo para cálculo de dose absorvida na água e não considera a composição dos materiais, densidades, dimensões do paciente e o efeito dos aplicadores. Estes efeitos podem ser significantes, conforme descrito pelo recente relatório da AAPM, Task Group report TG- 186, que define diretrizes para que sistemas de planejamento modernos, capazes de considerar as complexidades descritas acima, sejam implementados. Esta tese tem como objetivo contribuir para o aumento da exatidão dos planejamentos de tratamento braquiterápicos, seguindo as recomendações do TG-186 e indo além do mesmo. Um software foi desenvolvido para integrar planejamentos de tratamento e simulações pelo método de Monte Carlo (MC); modelos acurados, CAD-Mesh, foram utilizados para representar aplicadores braquiterápicos; Grandezas utilizadas para reportar dose absorvida, Dw,m (dose para água no meio) e Dm,m (dose para o meio no meio), foram calculadas para um tratamento de cabeça e pescoço, considerando a teoria para pequenas (SCT small cavity theory) e grandes cavidades (LCT large cavity theory); a componente da dose em razão do movimento da fonte foi avaliada para tratamentos de próstata e ginecológicos. Perfis de velocidade obtidos na literatura foram utilizados; medidas de velocidade de uma fonte braquiterapica foram realizadas com uma câmera de alta taxa de aquisição. Cálculos de dose obtidos usando MC (incluindo a composição e densidade dos tecidos, ar e o aplicador) mostram sobredoses de aproximadamente 5% dentro do volume alvo, em um tratamento ginecológico, quando comparados aos resultados obtidos com um meio homogêneo de água. Por sua vez, subdoses de aproximadamente 5% foram observadas ao considerar a composição dos tecidos e regiões com ar em um tratamento intersticial de braço. Um aplicador cilíndrico oco resultou na sobredose observada no caso ginecológico, ressaltando a necessidade de modelos acurados para representar os aplicadores. Os modelos CAD-Mesh utilizados incluem um aplicador Fletcher-Williamson, com blindagem, e um balão deformável para irradiação de mama. Os resultados obtidos com estes modelos são equivalentes aos obtidos com modelos geométricos convencionais. Este recurso pode ser conveniente para aplicadores complexos e/ou quando o projeto dos aplicadores for disponibilizado pelo fabricante. Cálculos de dose, com a composição real dos tecidos humanos, podem apresentar diferenças significativas em razão da grandeza adotada. Diferenças entre Dm,m e Dw,m (SCT ou LCT) chegam a 14% em razão da composição do osso. A metodologia adotada (SCT ou LCT) resulta em diferenças de até 28% para o osso e 36% para os dentes. A componente de dose de trânsito também pode levar a diferenças significativas, uma vez que baixas velocidades ou movimentos uniformemente acelerados foram descritos na literatura. Considerando a pior condição e sem incluir nenhuma correção no tempo de parada, a dose de trânsito pode chegar a 3% da dose prescrita para um caso ginecológico, com 4 cateteres, e até 11.1% da dose prescrita para um tratamento de próstata, com 16 cateteres. A dose de trânsito para a fonte avaliada (velocidade obtida experimentalmente) não é uniformemente distribuída e pode levar a sub ou sobredoses de até 1.4% das doses comumente prescritas (310 Gy). Os tópicos estudados são relevantes para tratamentos braquiterápicos e podem contribuir para o aumento de sua acurácia. Os efeitos estudados podem ser avaliados com o uso do software, associado a um código MC, desenvolvido. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP / FAPESP:11/01913-4
13

Racionalizace nákladů na malé elektrické stroje / Rationalization of Cost of Small Electrical Machines

Vítková, Eva Unknown Date (has links)
The doctoral thesis deals with the cost rationalization in the process of small electric machines production. The rationalization can be done on two different levels: technical and economic. The doctoral thesis is divided into two parts, each focusing on the particular level and describing the production processes in which it is possible to optimize the costs. The main part of the doctor thesis concentrates on the economic side of the problém. It presents and analyses the origin of the costs, their identification and classification.Production costs specification and calculation are analysed. Due to the fact that there are many possibilities of optimal production cost calculations used in the process of small electric machines production, much attention is devoted to possibile calculation methods and calculation formulas.
14

Kalkulace v podmínkách vybraného podnikatelského subjektu / Costing in the the Condition of the Company

Kubeš, Michal January 2017 (has links)
The master’s thesis is focused to analysis of current conditions of calculations and calculation system of company. The analysis are basis for finding and resolving of problematic sections. The introduction of theoretical basis of cost accounting and calculations is included to first part of the thesis. The second part analyzes of current situation of company and describes relevant processes. The wording of proposals and recommendations for problematic sections, which have been detected by analysis, are included to final part.
15

Využití controllingu v podniku / Application of Management Control System in a Company

Kutišová, Kristýna January 2017 (has links)
This Master's thesis is focused on dealing with cost variances (deviations) and using of standard costing method. The main intent is to analyse current state and make an improvement proposal of focusing on variables in company which is producing server PCs. This thesis is divided into three parts, which are theroretical part, analytic part and proposal part. The theoretical part is focused on characteristics of controlling, costs, calculation methods, especially standard costing method and focusing on variances. In next two parts is made the analysis of current state and then are suggested some improvement proposals.
16

Fatigue life analysis of weld ends : Comparison between testing and FEM-calculations

Göransson, Andréas January 2014 (has links)
The thesis examines the fatigue life of weld ends, where very little usable research previously has been conducted, and often the weld ends are the critical parts of the weld. It is essential knowing the fatigue life of welds to be able to use them most efficiently.The report is divided into two parts; in the first the different calculation methods used today at Toyota Material Handling are examined and compared. Based on the results from the analysis and what is used mostly today, the effective notch approach is the method used in part two.To validate the calculation methods and models used, fatigue testing of the welded test specimens was conducted together with a stress test. New modelling methods of the weld ends that coincide with the test results were made in the finite element software Abaqus. A new way of modelling the weld ends for the effective notch method is also proposed. By using a notch radius of 0.2 mm and rounded weld ends the calculated fatigue life better matches the life of the real weld ends.
17

Solucoes Psubn para os problemas da moderacao e do calculo de celula em geometria plana

CALDEIRA, ALEXANDRE D. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:43:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:29Z (GMT). No. of bitstreams: 1 06501.pdf: 3346863 bytes, checksum: c0335a4d0d89d17de7ff520ce20eae25 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
18

Řízení nákladů ve vybraném podniku / Cost management in the selected company

BENEŠOVÁ, Lenka January 2014 (has links)
Thesis focuses on cost management in chosen company. Theoretical part of thesis specifies costs and breakdown of costs. Subsequently, thesis analyzes calculation issue and used methods. Practical part of thesis characterizes chosen company from printing production sec-tor. Afterwards, the thesis analyzes methods of cost evidence, which company uses as a basis for price calculation of its production. To set the price correctly, company needs documentation that records important data about monitored facts. Subsequently, standard calculation procedure on a chosen contract is described. Thesis then presents analysis of enumeration with stated preliminary calculation and resulting calculation. Afterwards, the thesis evaluates used method and presents resulting calculation using ABC method with focus on administrative costs. After analysis of new calculation method thesis describes pros and cons of both used methods. Practical part ends with an example of ABC model implementation. Conclusion includes summary of results, answering the hypotheses and possible recommendations.
19

Aplicacao da metodologia fuzzy na quantificacao da probabilidade de erro humano em instalacoes nucleares / Human error probability quantification using fuzzy methodology in nuclear plants

NASCIMENTO, CLAUDIO S. do 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:13Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
20

Solucoes Psubn para os problemas da moderacao e do calculo de celula em geometria plana

CALDEIRA, ALEXANDRE D. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:43:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:29Z (GMT). No. of bitstreams: 1 06501.pdf: 3346863 bytes, checksum: c0335a4d0d89d17de7ff520ce20eae25 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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