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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

A Computer-Based Process Control System for a Target Station in a LINAC Facility

Al-Shantaf, Abdulraouf O. 05 1900 (has links)
An event-driven, sequential, process control system was designed for International Isotopes, Inc., to automate and remotely control a target station at the company's linear accelerator facility. The designed system consisted of two major sections: a software program (virtual instrument), which was developed by LabVIEW, and a hardware interface (FieldPoint Modular Distributed I/O System by National Instrument), which had to be a pre-developed system that did not require customization. The designed virtual instrument was tested on a simulation model that mimed the target station. The result was a valid design.
12

The design of linear accelerators

January 1947 (has links)
by J.C. Slater. / Bibliography: p. 66. / Army Signal Corps Contract No. W-36-039 sc-32037.
13

Application of Monte Carlo to linac bunker shielding design /

Dugal, Clifford January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 95-102). Also available in electronic format on the Internet.
14

Linac head scatter factor for asymmetric radiation field.

Soubra, Mazen Ahmed, January 1997 (has links)
Thesis (Ph. D.)--Carleton University, 1997. / Also available in electronic format on the Internet.
15

Análise quantitativa dos resultado dos testes de controle de qualidade em radioterapia / Quantitative analysis of results for quality assurance in radiotherapy

PASSARO, BRUNO M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:04Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:54Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
16

Análise quantitativa dos resultado dos testes de controle de qualidade em radioterapia / Quantitative analysis of results for quality assurance in radiotherapy

PASSARO, BRUNO M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:04Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:54Z (GMT). No. of bitstreams: 0 / Os aceleradores lineares representam a mais importante, prática e versátil produtores de raios-X de alta energia em radioterapia. O comportamento funcional destes equipamentos pode variar devido a defeitos eletrônicos, falhas de componentes ou rupturas mecânicas, ou então podem variar devido ao deterioramento e envelhecimento de seus componentes. A manutenção da qualidade dos tratamentos depende essencialmente da estabilidade dos aceleradores e do controle de qualidade das instituições para monitorar desvios nos parâmetros do feixe. O objetivo deste trabalho consiste em avaliar e analisar a estabilidade do fator de calibração dos aceleradores lineares, bem como os demais parâmetros dosimétricos normalmente incluídos em um programa de controle de qualidade em radioterapia. A média dos fatores de calibração dos aceleradores para o período de aproximadamente quatro anos para os Clinacs 600C e 6EX foram (0,998 ± 0,012) e (0,996 ± 0,014), respectivamente. Para o Clinac 2100CD de 6 MV e 15 MV foi (1,008 ± 0,009) e (1,006 ± 0,010), respectivamente, em um período de aproximadamente quatro anos. Através de análises estatísticas nos três aceleradores lineares verificou-se que os coeficientes de variação dos fatores de calibração apresentaram valores inferiores a 2% o que mostra uma homogeneidade nos dados. Através do cálculo da distribuição normal dos fatores de calibração, verificou-se que para os Clinacs 600C e 2100CD, é esperada uma probabilidade de que em mais de 90% dos casos os valores estejam dentro dos limites aceitáveis segundo o protocolo TG-142, enquanto que para o Clinac 6EX é esperado em torno de 85% uma vez que esse acelerador apresentou diversas trocas de componentes. Os valores do TPR20,10 dos três aceleradores são praticamente constantes e dentro dos limites aceitáveis segundo o protocolo TG-142. Pode-se concluir que um estudo detalhado dos dados do fator de calibração dos aceleradores e do TPR20,10 a partir de um ponto de vista quantitativo, é extremamente útil em um programa de garantia de qualidade. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
17

New method of collecting output factors for commissioming linear accelerators with special emphasis on small fields and intensity modualted readiation therapy

Unknown Date (has links)
Common methods for commissioning linear accelerators often neglect beam data for small fields. Examining the methods of beam data collection and modeling for commissioning linear accelerators revealed little to no discussion of the protocols for fields smaller than 4 cm x 4 cm. This leads to decreased confidence levels in the dose calculations and associated monitor units (MUs) for Intensity Modulated Radiation Therapy (IMRT). The parameters of commissioning the Novalis linear accelerator (linac) on the Eclipse Treatment Planning System (TPS) led to the study of challenges collecting data for very small fields. The focus of this thesis is the examination of the protocols for output factor collection and their impact on dose calculations by the TPS for IMRT treatment plans. Improving output factor collection methods, led to significant improvement in absolute dose calculations which correlated with the complexity of the plans. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
18

Geometry Estimation and Adaptive Actuation for Centering Preprocessing and Precision Measurement

Mears, Michael Laine 06 April 2006 (has links)
Precise machining of bearing rings is integral to finished bearing assembly quality. The output accuracy of center-based machining systems such as lathes or magnetic chuck grinders relates directly to the accuracy of part centering before machining. Traditional tooling and methods for centering on such machines are subject to wear, dimensional inaccuracy, setup time (hard tooling) and human error (manual centering).A flexible system for initial part centering is developed based on a single measurement system and actuator, whereby the part is placed by hand onto the machine table, rotated and measured to identify center of geometry offset from center of rotation, then moved by a series of controlled impacts or pushes to align the centers. The prototype centering system is developed as a demonstration platform for research in a number of mechanical engineering areas, particularly: Characterization of optimal state estimators through analysis of accuracy and computational efficiency; Distributed communication and control, efficient transfer of information in a real-time environment, and information sharing between processes; Modeling of sliding dynamics and the interaction of friction with compliant body dynamic models; Motion path planning through both deterministic geometric transforms and through frequency domain command manipulation.A vision is created for future work not only in the described areas, but also in the areas of advanced controller design incorporating multiple variables, derived machine diagnostic information, and application of the distributed communication architecture to information flow throughout the manufacturing organization. The guiding motivation for this research is reduction of manufacturing processing costs in the face of global competition. The technologies researched, developments made, and directions prescribed for future research aid in enabling this goal.
19

Multiple-source models for the beams from an Elekta SL25 clinical accelerator /

Sego, Zdenko, January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 113-119). Also available in electronic format on the Internet.
20

An investigation into EPID flood fields independent from the linear accelerator beam : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Medical Physics in the University of Canterbury, New Zealand /

Satory, Philip. January 1900 (has links)
Thesis (M. Sc.)--University of Canterbury, 2008. / Typescript (photocopy). "Year 2006-2008"--P. i. Includes bibliographical references (p. 122-123). Also available via the World Wide Web.

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