Дисертації: "Radiation Effects Analysi"

1

CAMPOS, ISIDA M. A. de. "Dosimetria biologica citogenetica em protecao radiologica .Analise de aberracoes cromossomicas radioinduzidas em linfocitos humanos." reponame:Repositório Institucional do IPEN, 1988. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9913.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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2

SOUZA, MARIA D. C. A. de. "Identificacao, quantificacao e comparacao das substancias quimicas responsaveis pelos aromas da cachaca de alambique e do rum comercial tratados pelo processo de irradiacao." reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11381.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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3

Le, Roux Jacques. "The analysis of radiation-induced micronuclei in peripheral blood lymphocytes for purpose of biological dosimetry." Master's thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/27038.

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In the investigation of radiation accidents, it is of great importance to estimate the dose absorbed by exposed persons in order to plan their therapy. Although occasionally in these situations physical dose measurements are possible, most often biological methods are required for dose estimation. The aim of this investigation was to assess the suitability of the cytokinesis blocked (CB) micronucleus assay as a biodosimetric method using lymphocytes irradiated in vivo. The approach adopted to achieve this was to estimate whole body doses by relating micronuclei yields in patients undergoing radiotherapy treatment with an in vitro radiation dose-response curve. These biologically derived estimates were then compared with the corresponding doses obtained by physical measurement and calculation. As a first approach a study was performed of the in vitro dose-response of gamma-ray induced micronuclei following cytokinesis-block in the lymphocytes of peripheral blood samples obtained from 4 healthy donors. The results indicated that the distribution of the induced micronuclei were overdispersed. Furthermore, a linear dose-response relationship was established when a curve was fitted to the data by an iteratively reweighted least squares method. By means of an analysis of covariance it was demonstrated that this result is in agreement with the dose-response relationships found by various other workers (Fenech et al., 1985; Fenech et al., 1986; Fenech et al., 1989; Balasem et al., 1992, and Slabbert, 1993). To assess the suitability and accuracy of dose assessment using the CB micronucleus assay for in vivo exposure of lymphocytes, blood samples obtained from 8 patients undergoing radiotherapy before, during and after treatment were examined. The physical doses of these patients were determined according to conventional radiation treatment plans and cumulative dose-volume histograms. The dose-volume histograms permitted calculation of integral doses and subsequently the estimate of equivalent whole-body doses. The results of the CB micronucleus assay applied to peripheral blood lymphocytes of 6 patients undergoing fractionated partial-body irradiation showed a dose-related increase in micronucleus frequency in each of the patients studied. This demonstrated that micronuclei analysis may serve as a quantitative biological measure of such exposures. The pooled data of these patients compared to the pooled data of the healthy donors show that there was no statistically significant difference between in vitro and in vivo results, however a slightly lower induced micronuclei frequency was observed after in vivo exposure. When the biological dose estimates for equivalent whole-body doses obtained from the in vitro dose response curve were compared with calculated physical doses, it was found that: biologically estimated dose = 0.936 physical dose. However, there was inadequate statistical evidence to discard the hypothesis that the gradient of the equation was equal to one. Therefore, the analysis of micronuclei induced in lymphocytes in vivo yields highly quantitative information on the equivalent whole-body dose. The negative binomial method was used for analysing the micronucleus data from two patients who received single, relatively larger tumour doses of 10 Gy each, with the objective to obtain estimates of the exposed body fraction and the dose to this fraction. The dose estimates to the irradiated volume were found to be within 30% of the physical tumour dose. The irradiated volume estimates seemed to be higher than the physically calculated volumes but by discarding the correction for the loss of cells due to interphase death the agreement was good between the physically and biologically determined integral doses. This study has revealed that the CB micronucleus assay appears to offer a reliable, consistent and relatively rapid biological method of whole body dose estimation. It is recognised that further corroborative work using the techniques described in this thesis is required for estimating localized exposure.

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4

SILVA, MURILO C. da. "Estudo das interacoes dos produtos de radiolise da agua com a miotoxina do veneno de Crotalus durissus terrificus." reponame:Repositório Institucional do IPEN, 2008. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11763.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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5

Faraud, Emeric. "Développement et applications de techniques laser impulsionnelles pour l'analyse de défaillance des circuits intégrés." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14677/document.

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Les techniques de localisation de défauts basées sur la stimulation laser restent aujourd'hui les techniques parmi les plus avancées qui existent. Elles permettent la stimulation thermique ou photoélectrique de façon très localisée sans contact physique. Les travaux dans ce mémoire sont consacrés au développement et à l’application de techniques d'analyse par faisceau laser impulsionnelles destinées à l'analyse des circuits intégrés. Le développement matériel et les investigations de méthodologies d'analyse ont été portés par la motivation du projet MADISON (Méthodes d’Analyse de Défaillances Innovantes par Stimulation Optique dyNamique), qui a pour but d'augmenter le taux de succès des analyses des circuits complexes VLSI par stimulation laser. L'utilisation de systèmes optiques très performants comprenant des sources laser impulsionnelles fibrées nous a permis d'explorer les capacités en termes d'analyse par stimulation laser photoélectrique impulsionelle. Une étude originale de l’étude du phénomène Latchup a montré une augmentation de la résolution latérale avec l'utilisation du processus d’absorption non linéaire
The fault location based on laser stimulation are now among the most advanced available techniques. They allow thermal or photoelectric stimulation localized without physical contact.This Ph.D works was devoted to the development and application of techniques using pulsed laser for integrated circuits’ analyses.Material development and investigation of analysis methodologies have been held by the motivation of the MADISON project (Methods of Analysis of Failures by Innovative Dynamic Optical Stimulation), which aims to increase the success rate analysis of complex circuits VLSI by laser stimulation.We used high-performance optical systems including fibered pulsed laser sources to explore the capabilities in terms of analysis by photoelectric laser stimulation. An original study of the Latchup phenomenon showed an improving lateral resolution by using nonlinear absorption process

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6

Walsh, Linda. "Quantifications of the detrimental health effects of ionising radiation." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/quantifications-of-the-detrimental-healtheffects-of-ionising-radiation(6b69e1c9-9c3d-486a-ac2c-908763b01a3a).html.

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A body of work and ensuing publications covering 2000–2012 are presented, predominantly concerning studies of various cohorts of people exposed to ionising radiation. The major areas cover epidemiological and statistical studies on the Life span study (LSS) cohort of Japanese survivors of the World War II atomic-bomb attacks on Hiroshima and Nagasaki and the mortality follow-up of German uranium miners. Following the presentation of a very brief history of the effects of radiation exposure on humans, the background and context of the advances achieved by the candidate are described. The LSS provides the most studied cohort and a range of topics from cancer risks related to neutron and γ-ray doses, organ specific doses, and carcinogenesis have been explored covering about half of the candidate’s publications. The cohort of German “Wismut” uranium miners exposed to radon and other potential carcinogens, which is the largest one of its kind, has enabled the development of epidemiological models for lung and extra-pulmonary cancers. The third distinct topic relates to analyses of data on cellular radiation damage relevant to the evaluation of both diagnostic radiation characteristics and the effects on cancer patients. Other studies have considered the incidence of malignant diseases in humans injected with radium-224 and development of epidemiological models for thyroid cancer risk in areas affected by the 1986 Chernobyl accident. Fundamental contributions have been published in the application of mathematical methods for data analysis. The candidate has succeeded in going beyond the traditional statistical methods in radiation epidemiology by introduction of numerical techniques deriving from the field of information science and novel to the field. These methods, such as techniques for model selection and mitigation of strongly correlated quantities, have been presented as general tools and have demonstrated powerful results, such as in applications to data from LSS. The impact and relevance for public health of the epidemiological results is indicated by their frequent citation in recent reports by international bodies such as by the International Commission on Radiological Protection, the United Nations Scientific Committee on the Effects of Atomic Radiation, the World Health Organization (WHO) and WHO-International Agency for Research on Cancer.Several topics, from among this broad coverage of radiation epidemiological themes, the development of novel statistical techniques and their application, are highlighted. Work on distinguishing the effect of neutrons and γ-rays in the Japanese LSS data has led to progress on quantifying their relative biological effectiveness with important consequences for the health effects of modern radiation diagnostics. A technique for combining risks from several risk models, called multi-model inference, has been shown to ease the dilemma of selecting between models with very different consequences, with particular relevance for major issues of public health concern connected with radiation exposure. The Wismut cohort has revealed for the first time the response characteristics of a significant effect of working underground on prostate cancer incidence, suggesting a relation with lack of exposure to light which remains unexplained.

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7

LOHMANN, TANIA H. O. "Analise da radiossensibilidade de linfocitos perifericos de pacientes com cancer de pele e de individuos sadios por meio do metodo do micronucleo." reponame:Repositório Institucional do IPEN, 1995. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10424.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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8

Bolin, Jennifer A. "Comparative analysis of selected radiation effects in Medium Earth Orbits." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA341085.

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Thesis (M.S. in Astronautical Engineering) Naval Postgraduate School, December 1997.
"December 1997." Thesis advisor(s): Vicente Garcia, Brij Agrawal. Includes bibliographical references (p. 95-99). Also available online.

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9

Samin, Adib J. Jr. "An analysis of neutron radiation effects on NdFeB permanent magnets." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1405899609.

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10

Sanchez, Maria Cristina. "Optical Analysis of a Linear-Array Thermal Radiation Detector for Geostationary Earth Radiation Budget Applications." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36536.

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The Thermal Radiation Group, a laboratory in the Department of Mechanical Engineering at Virginia Polytechnic Institute and State University, is currently working to develop a new technology for thermal radiation detectors. The Group is also studying the viability of replacing current Earth Radiation Budget radiometers with this new concept. This next-generation detector consists of a thermopile linear array thermal radiation detector. The principal objective of this research is to develop an optical model for the detector and its cavity. The model based on the Monte-Carlo ray-trace (MCRT) method, permits parametric studies to optimize the design of the detector cavity and the specification of surface optical properties. The model is realized as a FORTRAN program which permits the calculation of quantities related to the cross-talk among pixels of the detector and radiation exchange among surfaces of the cavity. An important capability of the tool is that it provides estimates of the discrete Green's function that permits partial correction for optical cross-talk among pixels of the array.
Master of Science

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11

CARNEIRO, JANETE C. G. G. "Contribuicao para avaliacao critica da radioprotecao por meio da analise retrospectiva das doses associadas ao trabalho com fontes nao seladas de iodo-131." reponame:Repositório Institucional do IPEN, 1998. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10724.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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12

Allman, Amy Jane. "Effects of UV radiation on Marfan syndrome cells in culture." Virtual Press, 1993. http://liblink.bsu.edu/uhtbin/catkey/879841.

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Ultraviolet radiation causes an alteration in DNA by modifying neighboring thymine bases resulting in the formation of a dimer. These dimers block the processes of transcription and translation and ultimately no protein is synthesized and the cell dies. However, DNA repair mechanisms correct this damage by excising the dimer from the DNA strand and inserting replacement bases which are joined to the original strand by DNA ligase. This allows transcription to resume and ultimately protein synthesis to take place.This research focused on determining the DNA damage and subsequent repair levels in a connective tissue disorder, namely Marfan syndrome. This information is important in understanding the clinical expression and management of life threatening conditions in Marfan syndrome individuals.Preliminary results indicate that at 20-25J/m2 UV dose (254nm) Marfan syndrome skin cells show a mean reduced survival value of 12% compared to normal human skin cells. Gel electrophoresis indicates a reduced DNA repair level 24h post UV irradiation for Marfan syndrome skin cells compared to normal human skin cells. These results suggest Marfan syndrome skin cells have reduced survival and DNA repair levels compared to normal human skin cells.
Department of Biology

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13

MAIO, MIREIA F. "Avaliacao dos efeitos da radiacao ionizante em materiais utilizados em restauracoes dentarias." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9408.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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14

Bolinder, Richard. "Atmospheric Radiation Effects Study on Avionics : An Analysis of NFF Errors." Thesis, Linköpings universitet, Programvara och system, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-96726.

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No fault found (NFF) errors, i.e. errors which origin has not been established, irregularly occur in electronic devices. The actual cause of such errors varies but one, possibly more prominent, source for these soft errors is atmospheric radiation. The overarching aim of this thesis is to demonstrate: 1) the importance of keeping the atmospheric radiation environment in mind when designing robust airborne systems, 2) how to take this environment into consideration when applying mitigation techniques which may drastically reduce the risk of SEEs (Single Event Effects) which can cause NFF errors. To achieve these goals, Part 1 of this thesis describes how cosmic rays affect electronics (i.e. what kind of errors may be induced), which types of devices are susceptible to radiation, and why this subject is of extra importance for airborne systems. In addition, soft error mitigation techniques, which may be applied at different design levels to reduce the soft error rate (SER) or the impact of soft errors, are also presented. The aim is further corroborated by Part 2. Five subsystems of a modern aircraft are studied and real examples of failures potentially induced by atmospheric radiation are presented. For each of the five systems, all errors that have been reported for these (in the past few years) have been studied, and the number of errors found to be potentially induced by cosmic radiation has been listed and compared to number of expected soft errors based on calculations and previous experimental tests.

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15

Martinez, Marino Juan 1965. "The analysis of current-mirror MOSFETs for use in radiation environments." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276910.

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Experiments were conducted on current-mirror MOSFETs to examine their suitability for use in radiation environments. These devices, which allow low loss load current sensing (defined by a current-ratio n'), are an important element of many power integrated circuits (PICs). Total-dose testing demonstrated that the current ratio was virtually unaffected for many operating conditions. In all cases, changes were largest when sense resistance was largest and minimal when sense voltage was approximately equal to the load source's voltage. In addition, testing verified the feasibility of using sense-cell MOSFETs for applications which require radiation exposure. A constant-current op-amp circuit showed minimal current shifts, using proper circuit design, following total-dose exposure. Dose-rate testing showed the feasibility of using sense voltage to trigger g&d2; protection through drain-source voltage clamping, providing a relatively inexpensive alternative to voltage derating.

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16

An, Ting. "Architectures d'opérateurs numérique auto-contrôlables." Thesis, Paris, ENST, 2014. http://www.theses.fr/2014ENST0054/document.

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La réduction géométrique régulière des finesses de gravure en microélectronique a conduit à un grand succès dans l'industrie et a beaucoup changé la vie humaine. Cependant, cette évolution technologie continue apporte de nouveaux défis aux circuits intégrés (CIs). Leur conception et fabrication sont de plus en plus complexes qu'avant. Les CIs sont affectés par deux phénomènes majeurs: la variabilité paramétrique et les limites des procédés de fabrication, ainsi que la sensibilité aux conditions environnementales. Avec l'augmentation du taux de défaillance lié à ces deux phénomènes, les circuits basés sur les technologies nanoélectroniques sont censés être de moins en moins fiables. Le critère de fiabilité est exigé dans les applications critiques. Parmi de nombreuses solutions techniques, l'amélioration au niveau de l'architecture profite de l'indépendance de la technologie et de la faible latence de réaction. Les solutions architecturales faisant l'objet de cette thèse sont du type auto-contrôlables, c'est-à-dire capables d'indiquer automatiquement l'apparition de fautes ou de masquer les fautes directement. Cette thèse est consacrée aux méthodes d'analyse et d'amélioration de la fiabilité au niveau de l'architecture. Les problèmes de fiabilité pendant la durée d'utilisation d'un circuit électronique sont décrits en détails. Les opérateurs arithmétiques numériques pour le traitement du signal sont pris comme des études de cas. Les opérateurs élémentaires (c-à-d additionneurs binaires), le calcul numérique par rotation de coordonnées (CORDIC) et le processeur du standard de chiffrement avancé (AES) sont également traités
The steady geometrical reduction of CMOS technology brought a great industry success and affected a lot the human life. However, the integrated circuits (ICs) are shrinking along with new challenges. The design and manufacturing are becoming more complex than before. ICs suffer from two major problems: the parametric variability in materials and limited precision processes, and the sensibility to environment noise. With the increasing failure rate related to these two problems, the future ICs implemented with sub-micron CMOS technology are expected to be less reliable. New reliable ICs are highly desired in critical applications such as avionic, transport and biomedicine. Numerous solutions have been reported in literature covering the enhancement in different abstraction levels (i.e., system level, architecture level and electrical level). Among these solutions, the improvement in architecture level benefits the independence from CMOS technology and the low latency of reaction. Expected architectural solutions will be self-controlled meaning that is able to either automatically indicate the occurrence of faults or directly mask the faults. This thesis is devoted to the reliability analysis methodology and reliability enhancement approaches on architecture level. In particular, the reliability issues in usage time are discussed in details. Digital arithmetic operators for signal processing are taken as studied objects. In addition to the basic operators (i.e., binary adders), coordinate rotation digital computer (CORDIC) and advanced encryption standard (AES) processor are also covered in the scope of this work

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17

Woods, Michael D. "A comparative analysis of radiation effects on silicon, gallium arsenide, and GaInP2/GaAs/Ge triple junction solar cells using a 30 MeV electron linear accelerator." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion/02Sep%5FWoods.pdf.

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18

Salih, Isam M. Musa. "Radon in natural waters : Analytical Methods; Correlation to Environmental Parameters; Radiation Dose Estimation; and GIS Applications." Doctoral thesis, Linköpings universitet, Medicinsk radiofysik, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5221.

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Investigations of radon in natural water and its relation to physical and chemical parameters are outlined in this thesis. In particular, a method for measuring 222Rn in water at low concentrations (~20 mBq.l-1) is described, followed by discussions concerning the design and its application to study both radon and parameters influencing radon levels in natural waters. A topic considered is the impact of fluoride and other aquatic parameters on radon in water. Moreover, variables such as uranium series radionuclides and stable elements in water, bedrock and sediment radioactivity and geology are investigated in two case studies. This was performed by employing radiometric-, chemical-, statistical- and GIS & geostatistical- analyses. The general water chemistry and presence of some elements such as fluoride was observed to influence radon levels in water. Health aspects of radon in drinking water are discussed based on radiation dose assessments. The radiation doses are compared with and added to doses incurred from ingestion of uranium, radium and polonium isotopes in drinking water and inhalation of radon in air in order to estimate total exposures for different age categories. The results may have a potential for future epidemiological studies.

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19

DeBolt, Frederick C. "Analysis of thermal effects produced by incident laser radiation on a structure /." Online version of thesis, 1991. http://hdl.handle.net/1850/10788.

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20

Foo, Kerwyn Yi Min. "Methodological uncertainties in radiotherapy dose-effect analysis." Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/24421.

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Cancer and normal tissues in patient populations exhibit variability in biological response to the same dose of radiation. Sources of this variability include: • Inherent biological factors of patient, tumour or tissue • Metrics to measure, classify or declare biological outcomes • Volumetric (prescription of target or avoidance regions) • Dosimetric and delivery Dosimetric and delivery variation is easily measured and has relatively little impact on variation of outcome in modelling studies. Volumetric variation contributes greatly to uncertainty, dependent on human judgement by oncologists. However, analysis methodology is generally overlooked as a source of variation in reported dose-effect results and is the subject of investigation in this thesis. Dosimetric and clinical data from clinical trials and prospective cohort studies have been used to illustrate the contribution of analysis methodology to variation in dose-effect relationships using evidence from prostate cancer radiation therapy. The primary data source is the Trans-Tasman Radiation Oncology Group clinical trial 03.04 “RADAR”, which investigated dose escalation in external beam radiotherapy for prostate cancer. Systematic review of the medical physics literature shows that prostate cancer radiotherapy toxicity reporting does not fully account for fractionation, which biases and causes unreported variation in dose-effect results. The toxicity-dose-volume-effect relationship is shown to depend on the anatomical subsite delineated and the type/grade of toxicity outcome chosen. Multivariate regression of multiple dose factors is not reliable due to multicollinearity of these factors. Heterogeneity in method of analysis is an important and overlooked component of variability in reported results of dose effect relationships in radiotherapy studies. Harmonisation of analysis or correction for this heterogeneity will reduce uncertainties to allow better modelling of biological effects in the molecular oncology era.

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21

Assis, Thiago Rocha de. "Analysis of transistor sizing and folding effectiveness to mitigate soft errors." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/31135.

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Este trabalho apresenta uma avaliação da eficiência do dimensionamento e particionamento (folding) de transistores para a eliminação ou redução de efeitos de radiação. Durante o trabalho foi construído um modelo de transistor tipo-n MOSFET para a tecnologia 90nm, utilizando modelos preditivos. O transistor 3D modelado foi comparado com o modelo de transistor elétrico PTM level 54 da Arizona State University e os resultados mostraram uma coerência entre os dispositivos. Este transistor modelado foi irradiado por uma série de partículas que caracterizam ambientes terrestres e espaciais. Foi descoberto que a técnica de redimensionamento de transistores tem sua eficiência relacionada ao tipo de partícula do ambiente e não é aplicável em ambientes com partículas com alta energia. Descobriu-se também que aplicando o particionamento de transistores é possível reduzir a amplitude e a duração de erros transientes. A combinação do dimensionamento e o particionamento de transistores pode ser utilizada para a redução de efeitos de radiação incluindo partículas leves e pesadas. Por fim um estudo de caso foi realizado com uma célula de memória estática de 6 transistores utilizando as técnicas mencionadas anteriormente. Os resultados da célula de memória indicaram que a combinação das duas técnicas pode de fato reduzir e até impedir a mudança do estado lógico armazenado na célula.
In this work the transistor sizing and folding techniques were evaluated for SET robustness in a 90nm MOSFET technology using a 3D device model. A n-type MOSFET transistor using a 90nm technology predictive profile was modeled and functional behavior compared with PTM level 54 model showing a fit of the device with the PTM. During simulations the modeled device was irradiated in a simulation environment using particles with the profile of sea and space level ions. The radiation effects simulation had indicated that the transistor sizing can be more or less efficient to reduce SET according to the collected charge. It was found that for environments with high energy particle, transistor sizing was not able to reduce soft errors intensity. The use of folding has shown significant reduction of the amplitude and duration of the transient pulse, making this technique very useful to reduce soft errors. For alpha particles and heavy ions the combination of transistor folding and sizing had shown to be an effective combination to enhance the reliability of the circuits. A 6T SRAM cell was modeled to evaluate transistor sizing and folding techniques and the results confirmed the efficiency of folding plus sizing to reduce the effects of radiation.

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ANDRADE, LUANA dos S. "Estudo do efeito da radiação ionizante em compostos orgânicos do diesel e do petróleo: hidrocarbonetos, sulfurados e nitrogenados." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11788.

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Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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23

EVORA, MARIA C. C. "Estudo do efeito da radiacao sobre a poliamida-6 reciclada." reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10958.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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24

Souza, Maria Djiliah Camargo Alvarenga de. "Identificação, quantificação e comparação das substâncias químicas responsáveis pelos aromas da cachaça de alambique e do rum comercial tratados pelo processo de irradiação." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-15052012-104641/.

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Quando aplicada em bebidas alcoólicas, a radiação ionizante pode ser usada para descontaminação de malte ou esterilização de mostos e tem sido proposta sua aplicação na aceleração do envelhecimento. Devido à internacionalização da cachaça, alguma confusão tem surgido sobre a sua identidade e a do rum. Este trabalho teve como propósito identificar, quantificar e comparar as substâncias químicas responsáveis pelo aroma de amostras de cachaça de alambique e de rum comercial, por meio de análises instrumentais e sensoriais. Pode-se afirmar haver forte correlação entre a concentração dos compostos voláteis analisados com a dose de radiação aplicada (0, 150 e 300Gy), em todas as amostras. De acordo com os testes triangulares, apenas para aroma, todos os provadores puderam distinguir nas amostras não irradiadas e irradiadas com 300Gy, a cachaça envelhecida do rum e a cachaça não envelhecida do rum, porém, não foram observadas diferenças entre a cachaça não envelhecida e a envelhecida. Os resultados da Análise Descritiva Quantitativa mostraram que as amostras não irradiadas de cachaça não envelhecida e as do rum diferiram entre si em relação aos atributos de aroma definidos como álcool, vinagre, baunilha, citros, melão, condimento, vegetal e grama, mas não em relação aos atributos caramelo e maçã. As amostras de cachaças não envelhecidas não irradiadas e irradiadas (300Gy) e as de rum não irradiadas e irradiadas (300Gy) diferiram entre si em relação aos atributos de aroma definidos como maçã, caramelo, vinagre, baunilha, citros, melão, condimento, vegetal e grama, mas não em relação ao aroma de álcool. De acordo com os resultados da cromatografia gasosa/olfatometria foi encontrada diferença significativa entre cachaça e rum não irradiados; cachaça não irradiada e cachaça irradiada (300Gy); e rum não irradiado e irradiado (300Gy), quando foram comparados seus aromas.
The irradiation process has being presented as an alternative technique in food preservation. When apply on beverages, radiation is mainly used for malt decontamination or sterilization of musts and had been proposed also to accelerate aging. Some confusion over rum and cachaça identities has arisen due to the internationalization of cachaça. This research aims to identify, quantify and compare the effect of gamma radiation on the aroma of the Brazilian spirit with rum, irradiated and non irradiated, by instrumental and sensory analysis. Results showed that the content of volatile compounds presented strong correlation with the radiation dose (0, 150 and 300Gy) for all the samples. According to Triangle Test for aroma, all the judges could distinguish among non irradiated and irradiated samples (300Gy), aged cachaça from rum and non aged cachaça from rum, but they couldn\'t distinguish aged cachaça from non aged cachaça. Analysis of variance (ANOVA) of the results from the quantitative descriptive analysis showed that non irradiated non aged cachaça and rum were different in their alcohol, vinegar, vanilla, citrus, melon, spice, vegetal and grass except caramel and apple aroma attributes. Non irradiated cachaça and irradiated cachaça (300Gy); and non irradiated rum and irradiated rum (300Gy) were different in their apple, caramel, vinegar, vanilla, citrus, melon, spice, vegetal and grass except alcohol aroma attributes. According to the gas chromatography/olfatometry results, significant difference was found among non irradiated cachaça and rum; non irradiated cachaça and irradiated cachaça (300Gy); and non irradiated rum and irradiated rum (300Gy) when their aromas were compared.

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25

Ebrahimiketilateh, Nasim. "Predicting Tolerance Effects on The Radiation Pattern of Reflectarray Antennas Through Interval Analysis." Doctoral thesis, Università degli studi di Trento, 2018. https://hdl.handle.net/11572/368584.

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The thesis focuses on predicting tolerance effects on the radiation pattern of reflectarray antennas through Interval Analysis. In fact, the uncertainty on the actual size of all parameters under fabrication tolerates such as element dimensions and dielectric properties, are modeled with interval values. Afterwards, the rules of Interval Arithmetic are exploited to compute the bounds of deviation in the resonance frequency of each element, the phase response of the element and the radiated power pattern. Due to the redundancy problems of using Interval Cartesian (IAâˆ’CS) for complex structure, the interval bounds are overestimated and the reasons are the Dependency and Wrapping effects of using interval analysis for complex structures. Different techniques are proposed and assessed in order to eliminate the dependency effect such as reformulating the interval function and the Enumerative interval analysis. Moreover, the Minkowski sum approach is used to eliminate the wrapping effect. In numerical validation, a set of representative results, show the power bounds computations with Interval Cartesian method (IA âˆ’ CS), a modified Interval Cartesian method (IA âˆ’ CS*), Interval Enumerative method (IA âˆ’ ENUM) and Interval Enumerative Minkowski method ( IA âˆ’ ENUM âˆ’ MS) and a comparative study is reported in order to assess the effectiveness of the proposed approach (IA âˆ’ ENUM âˆ’ MS) with respect to the other methods. Furthermore, different tolerances in patch width,length, substrate thickness and dielectric permittivity are considered which shows that the higher uncertainty produces the larger deviation of the pattern bounds and the larger deviation include the smaller deviation and the nominal one. To validate the inclusion properties of the interval bounds, the results are compared with Monte Carlo simulation results. Then, a numerical study is devoted to analyse the dependency of the degradation of the pattern features to steering angle and the bandwidth. Finally, the effect of feed displacement errors on the power pattern of reflecttarray antennas is considered with Interval Enumerative Minkowski method. The maximal deviations from the nominal power pattern (error free) and its features are analysed for several reflectarray structures with different focal-length-to-diameter ratios to prove the effectiveness of the proposed method.

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26

Mars, Johan Andre. "The application of nuclear microprobe analysis in materials science." Thesis, Peninsula Technikon, 2003. http://hdl.handle.net/20.500.11838/1513.

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Thesis (DTech (Science))--Peninsula Technikon, Cape Town, 2003.
The impetus for the refinement and renewal of daily-used products has spurred international interest in investigating the small in homogeneities that might exist in these products. This interest has become an important part in the design philosophy, which is based on structural information gained by the analysis of these products. It is this drive that initiated the study to investigate the simultaneous use of novel nuclear analytical techniques such as micro proton induced X-ray emission( u-PlXE), micro proton induced gamma-ray emission (u-PlGE) and micro proton backscattering (u-RBS) to achieved a broader and yet deeper insight into the fine structure of products. The fundamental underlying physical principles of these techniques are discussed to gain in-depth knowledge on how to them to obtain the desired information. Also determined was the degree of accuracy that could be attained in the application of this knowledge. These principles were evaluated in conjunction with the instrumentation with which the applicability of these techniques could then be further extended. More so is the use of sophisticated software that facilitated the use of both physical and instrumental parameters. After describing the necessary implements to achieve this further know-how, products of industrial origin were investigated to determine in homogeneities that existed in those products and compared those theoretical values. The first application was made to ceramic-based sorption electrodes to be used in the purification of wastewater.

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27

Liang, Li Heng. "Statistical analysis and biological effects of prostate motion in ultrasound image-guided external beam radiotherapy." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81359.

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Biological effects and prostate motion were studied for prostate cancer patients treated with external beam radiotherapy. The prostate motion was determined using an ultrasound-based patient positioning system (BAT: B-mode Acquisition and Targeting) just after conventional patient setup. The changes in planned biological effects due to prostate motion were calculated for the prostate target organ and for the rectum and bladder normal tissues using TCP (tumor control probability) and NTCP (normal tissue complication probability) calculations, respectively. The prostate TCP calculations were carried out for both prostate PTV and GTV structures, whereas the rectum and bladder wall structures were used for the NTCP calculations.

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28

Kohler, Pierre. "Méthodes de caractérisation et analyse de la sensibilité aux effets des radiations de mémoires dynamiques basse consommation pour application spatiale." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS003.

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Les composants électroniques embarqués dans des applications spatiales sont exposés à différents types de particules qui composent l’environnement radiatif spatial. L’interaction de ces particules avec les matériaux constituant les circuits intégrés est à l’origine d’effets singuliers ou d’effets de dose qui peuvent altérer la fiabilité des systèmes en induisant différents types de défaillances à l’échelle des fonctions électroniques élémentaires, et mettre en péril les missions satellitaires. En vue de prédire les taux d’évènement au cours d’une mission ou la durée de vie des composants en environnement radiatif, préalablement à leur intégration dans une application spatiale, il est nécessaire de comprendre les mécanismes physiques induits et de caractériser le fonctionnement des composants sous irradiation.Dans ce contexte, nous présentons l'élaboration et la mise en oeuvre de méthodes de caractérisation de la sensibilité des mémoires dynamiques SDRAM DDR3 aux effets des radiations en vue de leur future intégration dans des modules mémoires pour application spatiale. Le développement d’un banc de test fonctionnel et paramétrique compatible avec différents moyens d’irradiations est présenté. Les résultats d’essais obtenus sous rayonnement gamma, sont analysés et complétés par une estimation de la sensibilité des composants obtenue sous rayons X. Une campagne de caractérisation sous ions lourds, associée à l’utilisation d’un outil laser, permet de présenter une analyse comparative de la sensibilité des composants aux évènements singuliers. La complémentarité de ces techniques ainsi que les avantages et inconvénients des outils laser et rayons X sont discutés
Electronic components, embedded in space applications, are exposed to different types of particles that make up the space radiation environment. The individual or cumulative interaction of these particles with the integrated circuits materials is the source of single-event effects or dose effects that can alter the reliability of the systems by inducing different types of failures at basic electronic functions level and threaten the mission success. In order to predict the event rate during a mission or the components lifetime in a radiative environment, prior to their integration into a space application, it is necessary to model these failures and to characterize the functioning of the components under irradiation.In this context, the objectives of this thesis are the development and implementation of models and methods for characterizing the sensitivity of DDR3 SDRAM memories to the radiation effects for their future integration into memory modules for space applications. The development of a functional and parametric test bench compatible with various irradiation facilities is presented. Results obtained under gamma radiation, are analyzed, and supplemented by sensitivity estimation using X-rays. A characterization campaign under heavy ions, combined with laser testing, allows us to present comparative analysis of the components SEE sensitivity. The complementarity of these

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29

Birgisson, Helgi. "Cancer of the Colon and Rectum : Population Based Survival Analysis and Study on Adverse Effects of Radiation Therapy for Rectal Cancer." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6824.

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30

NISTI, MARCELO B. "Sistema Ambiental aplicado a liberacao de efluentes radioativo liquido." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9390.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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31

Herrick, Andrea Celeste. "A Comparative Dosimetric Analysis of the Effect of Heterogeneity Corrections Used in Three Treatment Planning Algorithms." University of Toledo Health Science Campus / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=mco1290427283.

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32

Li, Yang. "Fragilisation des aciers de cuve irradiés : analyse numérique des mécanismes de plasticité à l’aide de simulations de dynamique des dislocations." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLN031/document.

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Ce travail est une contribution à l’étude de la dégradation des propriétés mécaniques des matériaux métalliques irradiés, dans le contexte de la production d’énergie nucléaire. Cette thèse porte en particulier sur l’étude du comportement des dislocations dans les matériaux ferritiques irradiés, à l’aide de simulations de dynamique des dislocations (DD).L’évolution de la microstructure des défauts d’irradiation est tout d’abord analysée à l'aide d’un code nodal (code NUMODIS). Le Chapitre 2 traite en particulier de la diffusion et l’interaction de boucles prismatiques, en utilisant la dynamique des dislocations dite «stochastique». Ces calculs reproduisent les forces d’interaction élastiques boucle/boucle et les forces stochastiques associées aux fluctuations thermiques ambiantes. Il est ainsi montré que la réorientation des boucles (tilt) a un fort effet sur leur dynamique, en ce qui concerne notamment le taux d’évolution du confinement élastique boucle/boucle.L'effet du glissement dévié sur l’interaction entre dislocation/boucle est ensuite examiné au Chapitre 3. Cette étude fait appel à une configuration initiale spécifique, associée à un changement du plan de glissement d'une source de dislocation vis. De cette manière, il est montré que le glissement dévié réduit considérablement la résistance des défauts/obstacles. Cet effet confirme le rôle critique du glissement dévié durant la déformation plastique post-irradiation.La déformation plastique post-irradiation est étudiée à l’échelle du grain, au Chapitre 4, à l’aide de simulations DD à base de segments (code TRIDIS). Ces simulations traitent les mécanismes de glissement dévié et de glissement thermiquement activé (vis). Chaque condition d’irradiation simulée peut être caractérisée par un «décalage de la température apparente induite par des défauts d’irradiation» (ΔDIAT). Cette quantité est proportionnelle aux évolutions statistiques de la mobilité effective des dislocations. Le ΔDIAT calculé est pratiquement équivalent au décalage de la température de transition fragile à ductile (ΔDBTT) obtenu expérimentalement, pour une taille et densité de défauts d’irradiation donnée. Cette corrélation ΔDIAT/ΔDBTT peut être interprétée à partir de mécanismes de déformation plastique élémentaires, faisant appel à la théorie des dislocations
The interplay between radiation-generated defects and dislocation networks leads to a variety of changes in mechanical properties and results in a detrimental effect on the structural reactor component lifetime. The present PhD work focuses on studying elementary and collective dislocation mechanisms in irradiated iron-based materials, by means of dislocation dynamics (DD) simulations.Evolutions of the radiation-induced defect microstructure are studied first. Namely, the 1D diffusion of interacting prismatic loops is analyzed using the stochastic dislocation dynamics approach, accounting for the elastic forces acting between the loops and the stochastic forces associated with ambient thermal fluctuations. It is found that the interplay between stochastic forces and internal degrees of freedom of loops, in particular the loop reorientation, strongly influences the observed loop dynamics, especially the reaction rates resulting in the elastic confinement of loops.The cross-slip effect on the dislocation/loop interactions is then examined using a specific initial configuration associated with the glide plane change of a screw dislocation source, due to a single and well defined cross-slip event. It is shown that cross-slip significantly affects the effective strength of dislocation/defect interactions and therefore, post-irradiation plastic strain spreading.Lastly, post-irradiation plastic strain spreading is investigated at the grain scale using segment-based dislocation dynamics simulations, accounting for the thermally activated (screw) dislocation slip and cross-slip mechanisms. It is shown that each simulated irradiation condition can be characterized by a specific “Defect-Induced Apparent Straining Temperature shift” (ΔDIAT) level, reflecting the statistical evolutions of the effective dislocation mobility. It is found that the calculated ΔDIAT level closely matches the ductile to brittle transition temperature shift (ΔDBTT) associated with the corresponding, experimentally-observed defect size and number density. This ΔDIAT/ΔDBTT correlation can be explained based on plastic strain spreading arguments

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33

Virmontois, Cédric. "Analyse des effets des déplacements atomiques induits par l’environnement radiatif spatial sur la conception des imageurs CMOS." Thesis, Toulouse, ISAE, 2012. http://www.theses.fr/2012ESAE0009/document.

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L' imagerie spatiale est aujourd'hui un outil indispensable au développement durable, à la recherche et aux innovations scientifiques ainsi qu’à la sécurité et la défense. Fort de ses excellentes performances électro-optiques, de son fort taux d’intégration et de la faible puissance nécessaire à son fonctionnement, le capteur d’images CMOS apparait comme un candidat sérieux pour ce type d’application. Cependant, cette technologie d’imageur doit être capable de résister à l’environnement radiatif spatial hostile pouvant dégrader les performances des composants électroniques. Un nombre important d’études précédentes sont consacrées à l’impact des effets ionisants sur les imageurs CMOS, montrant leur robustesse et des voies de durcissement face à de telles radiations. Les conclusions de ces travaux soulignent l’importance d’étudier les effets non-ionisants, devenant prépondérant dans les imageurs utilisant les dernières évolutions de la technologie CMOS. Par conséquent, l’objectif de ces travaux de thèse est d’étudier l’impact des effets non-ionisants sur les imageurs CMOS. Ces effets, regroupés sous le nom de déplacements atomiques, sont étudiés sur un nombre important de capteurs d’images CMOS et de structures de test. Ces dispositifs sont conçus avec des procédés de fabrication CMOS différents et en utilisant des variations de règle de dessin afin d’investiguer des tendances de dégradation commune à la technologie d’imager CMOS. Dans ces travaux, une équivalence entre les irradiations aux protons et aux neutrons est mise en évidence grâce à des caractéristiques courant-tension et des mesures de spectroscopie transitoire de niveau profond. Ces résultats soulignent la pertinence des irradiations aux neutrons pour étudier les effets non-ionisants. L’augmentation et la déformation de l’histogramme de courant d’obscurité ainsi que le signal télégraphique aléatoire associé, qui devient le facteur limitant des futures applications d’imagerie spatiale, sont évalué et modélisés. Des paramètres génériques d’évaluation des effets des déplacements atomiques sont mis en évidence, permettant de prévoir le comportement des capteurs d’images CMOS en environnement radiatif spatial. Enfin, des méthodes d’atténuation et des voies de durcissement des imageurs CMOS limitant l’impact des déplacements atomiques sont proposées
Today, space imaging is an essential tool for sustainable development, research and scientific innovation as well as security and defense. Thanks to their good electro-optic performances and low power consumption, CMOS image sensors are serious candidates to equip future space instruments. However, it is important to know and understand the behavior of this imager technology when it faces the space radiation environment which could damage devices performances. Many previous studies have been focused on ionizing effects in CMOS imagers, showing their hardness and several hardening-by-design techniques against such radiations. The conclusions of these works emphasized the need to study non-ionizing effects which have become a major issue in the last generation of CMOS image sensors. Therefore, this research work focuses on non-ionizing effects in CMOS image sensors. These effects, also called displacement damage, are investigated on a large number of CMOS imagers and test structures. These devices are designed using several CMOS processes and using design rule changes in order to observe possible common behaviors in CMOS technology. Similarities have been shown between proton and neutron irradiations using current-voltage characteristics and deep level transient spectroscopy. These results emphasize the relevance of neutron irradiations for an accurate study of the non-ionizing effects. Then, displacement damage induced dark current increase as well as the associated random telegraph signal are measured and modeled. Common evaluation parameters to investigate displacement damage are found, allowing imager behavior prediction in space radiation environment. Finally, specific methods and hardening-by-design techniques to mitigate displacement damage are proposed

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PEREIRA, MARCO A. dos S. "Estudo da acao da radiacao gama de sup(60)Co sobre Salmonella poona, Escherichia coli e Alicyclobacillus Acidoterrestris em polpa de manga congelada." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9425.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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35

SOUZA, FABIO R. de. "Analise do grau de resistencia a flexao de femures de ratos irradiados com laser de dioxido de carbono." reponame:Repositório Institucional do IPEN, 2002. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11526.

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Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia)
IPEN/D-MPLO
Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo

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36

Gupta, Viyas. "Analysis of single event radiation effects and fault mechanisms in SRAM, FRAM and NAND Flash : application to the MTCube nanosatellite project." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS087/document.

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L’environnement radiatif spatial est un environnement sévère qui agit sur tout composants électroniques embarqués sur des engins spatiaux, y compris sous le bouclier naturel que nous procure le champ magnétique terrestre en orbite basse. Bien qu’il soit possible, en particulier à ces orbites, de se protéger efficacement contre les particules créant de la dose totale ionisante, cela pose plus de difficultés pour les particules générant des effets singuliers. Cela est d’autant plus un problème que l’utilisation des composants commerciaux (dits « COTS »), non conçus pour de telles applications, sont de plus en plus utilisés. Dans le cadre de cette thèse, les effets singuliers sur trois types de mémoires sont étudiés: SRAM, FRAM et NAND Flash. En se basant sur l’analyse des résultats de tests, les mécanismes d’erreurs induits par des particules générant des effets singuliers sont analysés. Avec pour objectif d’étudier et comparer la sensibilité de ces mémoires directement en orbite, l’expérience RES (Radiation Effect Study) a été développée et est présentée dans ce manuscrit. Cette expérience scientifique constituera la charge utile du nanosatellite de type CubeSat nommé MTCube (Memory Test CubeSat) developpé à l’Université de Montpellier en collaboration entre le Centre Spatial Universitaire Montpellier-Nîmes, et les laboratoires LIRMM et IES. Ce nanosatellite est financé par l’ESA (Agence Spatial Européenne)
Space radiation is a harsh environment affecting all electronic devices used on spacecraft, despite the presence of Earth’s protective magnetic field in Low Earth Orbit (LEO). Although particles inducing total ionizing dose (TID) can be effectively shielded against in LEO, particles responsible for Single Event Effects (SEEs) remain an issue for the reliability of electronics. This is particularly of concern considering the increasing use of Commercial-Off-The-Shelf (COTS) components, not designed for space applications. In the frame of this thesis, the SEE response of three commercial memory types are explored: SRAM, FRAM and NAND Flash. Based on SEE test results, the possible fault mechanisms induced by SEE particles on those devices are analysed. In order to study and compare the devices’ response with actual in-orbit measurements, the RES (Radiation Effect Study) science experiment was developed and is presented. The RES experiment will be the payload of the MTCube (Memory Test CubeSat) nanosatellite, which is being developed at the University of Montpellier as a joint project between the University Space Center (CSU Montpellier-Nîmes), as well as the LIRMM and IES laboratories. MTCube is financed by the European Space Agency (ESA)

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37

Romero, Faviola. "In-orbit performance analysis of the image sensors from Pleiades mission." Thesis, Luleå tekniska universitet, Rymdteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-66934.

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The image sensors embedded in the instruments on board of different satellites are a key aspect in the success of a mission of any type such as Earth observation, astronomy or planetary and universe exploration. The quality of the sensor itself as well as the electronics embedded in the instrument suffer from aging, not only due to the usage, but also due to the space environment factors. The outer space harsh environment is composed of charged particles with an incredibly high energy that can get through the shielding of the spacecraft thus causing damage to the sensors, or any part of the spacecraft. After a satellite is placed in orbit, there is no other way to check on its condition than to analyse the data transmitted to the ground stations. It is well known that we can measure the evolution of the instrument’s detection unit by measuring the variation of the quality of the images taken in orbit. As it has been done in past work, the atypical behaviour can be detected at a pixel level by analysing the images taken in orbit, preferably in complete darkness to discard any parasitic light. Past analysis of the dark images from the sensors on board the Picard, SPOT4 and Sentinel2A mission, proposed a classification of the different atypical behaviour that a pixel can show, such as hot, transitory-hot or RTS. By the end of the mission this defects may even be present in several pixels. The purpose of this work is to process the dark images obtained on orbit, at the end of the mission PLEIADES, to better understand the behaviour both Panchromatic and Multispectral CCD sensors and the differences in performance with respect to the tests made previously on ground. For this, a description of the framework of the PLEIADES mission and the technical design aspects of the CCD sensors on board are presented. Subsequently, the different image processing techniques used and developed are described, along with the tests made to get to the positive conclusion of no major anomalies detected in the PLEIADES images sensors. The analysis is done by means of new set of functions adjusted to the structure of the data, as well as the same detection software used in the previous analysis. Finally, a discussion is presented along with a further perspective for the analysis of future sets of data.

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GUIMARAES, FILHO RUBENS. "Efeitos da radiacao do laser de dioxido de carbono ( COsub(2) ) no tecido osseo: analise em microscopia optica e microscopia eletronica de varredura." reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10862.

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Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia)
IPEN/D-MPLO
Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo

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39

Wase, Nishikant V. "Proteomic and metabolomic analysis of the effects of UV-A radiation on the cyanobacterium nostoc punctiforme ATCC 29133." Thesis, University of Sheffield, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.557618.

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Over the last two decades, thinning of the ozone layer has raised serious concerns throughout the world, since it allows penetration of harmful ultraviolet radiation (UV-R) onto the Earth. Ultraviolet radiation (UV-R, 280-400 nm) has both direct and indirect effects on living organism. Both UV-A and UV-B have deleterious effect on living organisms. Numerous studies were undertaken in the past that have attempted to elucidate the biological effect of UV-B on photosynthetic organisms such as higher plants and microbes such as green algae and cyanobacteria, but there is only very limited knowledge about the effect of UV-A radiation on photosynthetic organisms. In the context of climate change and ozone depletion, it is clearly beneficial to understand the physiological and underlying molecular mechanism of UV-A response of cyanobacteria. This thesis primarily serves to generate understanding of response of cyanobacterium at the proteome and metabolome level in response to UV-A radiation. During this PhD project, a cyanobacterium was selected as an organism of choice because it has a geological past that can traced back to the Precambrian era, long before the production of the present ozone layer. Because of their geological past, cyanobacteria were thought to be well equipped in sustaining UV-R. In the present study, the filamentous cyanobacterium Nostoc punctiforme ATCC 29133 was used as a model organism to understand the effect of UV-A radiation on the physiology and the underlying molecular response. In order to assess the effects that environmental UV-A perturbation has on regulatory networks and pathways of N. punctiforme, a quantitative proteomics investigation was performed using soluble proteome sample. A total of 572 unique proteins were found in both studies constituting 8.41 % of the total proteome. Effect of short-term exposure (4h, 12h, 24h) and long-term exposure (20 days) was elucidated with the recent and powerful mass spectrometry based approach using iTRAQ (isobaric tag for relative and absolute quantification) methodology. Approximately, 32 and 61 proteins were found significantly changed in abundance during short-term and long-term exposure respectively. Abundance of some of the metabolically important proteins (13) were assessed using pSRM (pseudo selected reaction monitoring) and a strong correlation with the iTRAQ dataset was observed. Further, using HPLC, it was observed that UV-A has strong effect on photosynthetic accessory pigments (UV-A treatment period 4, 8, 12, 24 hours, 3, 5, and 7 days). An initial increase in carotenoids, ~-carotene, astaxanthin, and zeaxanthin was observed which later on decreased. An induction of scytonemin production during an acclimatization phase (4 hrs) was also observed. Using GC-MS, 62 compounds of known chemical structures were identified. Statistically significant elevated levels of glycine, alanine, tyrosine, proline, malate and succinic acid was observed (treatment interval periods 1, 3, 5, 7, 9, and 11 days), indicating a possible role of these metabolites during UV-A stress. Under prolonged exposure, UV-A not only substantially retarded the growth of N. punctiforme but a lowered abundance of photosynthetic apparatus and phycobilisomes was also observed. A number of targets (3 proteins) that are believed to have a strong role in the UV-sensing and signal transduction were also identified. Additionally, it was observed that long-term exposure causes the induction of increased protein scaffolding, redox rebalancing, and DNA repairing. In contrast, short-term exposure causes an immediate response from both the primary photosynthetic machineries, and also the secondary pigmentation apparatus. Additiona"y increased abundance of heat shock proteins was observed in both short-term and long-term treatment condition. Fina"y, a comparison of iTRAQ and pSRM data reaffirms the caveat regarding underestimation of quantitative measurements using iTRAQ. As a thesis closure, a comprehensive proteomics and metabolomics characterization of effect of UV-A stress in a model cyanobacterium N. puncfiforme ATCC 29133 is presented. The compilations of established analytical tools used to infer both qualitative and quantitative biological observations can also be adapted to other systems. Suggestions for future work are made.

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40

Choi, Hong Kyu. "Analysis and modeling of the long-term performance of amorphous photovoltaic arrays." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184835.

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A validated predictive model of a-Si:H solar cell arrays was developed. The performance of a-Si:H solar cells was modeled by predicting the performance before degradation first, and then modifying it with terms that account for degradation and recovery effects. A unique approach for the determination of the fundamental rate controlling parameters for the degradation and recovery process was carried out by observing the variation of the short-circuit current. The experimental annealing of a-Si:H silicon samples showed that the percent recovery from the degraded state to the as-grown state by annealing was virtually independent of the initial state at the start of the annealing process. This allowed the recovery parameters to be determined independently of the prior degradation process. An extremely simple and fast running algorithm for the long-term performance was developed in terms of the incident solar radiation, the panel temperature, and the total radiation exposed. Also it was found that the entire process of the Staebler-Wronski effect could be adequately represented by a correlation in which the degradation and recovery processes are solely a function of the total radiation exposure of the panel at ambient conditions.

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41

Ficuciello, Antonio. "Analyse des effets acoustiques à haute fréquence/haute intensité sur l'injection coaxiale : application aux moteurs-fusées." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMR106/document.

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Le contexte de ce travail repose sur l'étude des instabilités de combustion au sein des moteurs-fusées à propergols liquides. Cette étude se concentre sur les effets des champs acoustiques transverses de haute amplitude sur l'injection coaxiale en conditions non-réactives. La réponse acoustique du système d'injection est dépendante des propriétés locales du champ acoustique dans la cavité d'injection. La modification du processus d'atomisation, induit par le champ acoustique, a été analysée dans des configurations simples et multiinjection. Des expériences ont été menées pour des régimes d'atomisation de faibles et hauts nombres de Weber. Trois phénomènes ont été observés: un aplatissement du jet, une amélioration du processus d'atomisation et la déviation du système liquide. La combinaison de ces trois phénomènes en configuration multi-injection résulte en un phénomène de regroupement de gouttes. En présence de combustion, un tel regroupement pourraitmener à un dégagement de chaleur non-uniforme susceptible de déclencher ou d'entretenir des instabilités de combustion. Un modèle théorique basé sur les équations d'acoustique non-linéaire a été développé pour donner les expressions générales de pression de radiation et de forces de radiations résultantes appliqué aux objets sphériques et cylindriques en champ stationnaire ou progressif. Le modèle a été utilisé pour interpréter et quantifier les observations expérimentales en configurations liquide/gaz, trans-critique/super-critique et gaz/gaz, et a permis de montrer que le nombre de Helmholtz qui caractérise le champ acoustique, et le rapport de densité qui caractérise les deux milieux, sont deux paramètres cruciaux. Les principales conclusions montrent que le phénomène observé peut être interprété comme résultant de l'acoustique non-linéaire, dont le paramètre clé étant le ratio de densité. Cela exige que la couche séparant les deux milieux, vue comme une interface, ne doive pas être réduite uniquement à une interface liquide/gaz
The context of this work relies to high frequency combustion instabilities in Liquid Rocket Engines (LRE). The present research focuses on the effects of high amplitude transverse acoustic fields on non-reactive coaxial injection. The acoustic response of injection domes is found to be dependent on the local properties of the acoustic field in the injection cavity. The modification of the atomization process, induced by the acoustic field, has been analyzed in single and multi-injection configurations. Experiments were performed from low to high Weber number atomization regimes. Three phenomena are observed: jet flattening, improvement of the atomization process and deviation. The combination of these phenomena in multi-injection configurations leads to a droplet clustering phenomenon. In the presence of combustion, such a clustering could lead to non-uniform heat release rate which can trigger or sustain combustion instabilities. A theoretical model based on non-linear acoustics has been developed, providing general expressions of radiation pressure and resulting radiation force, for spherical and cylindrical objects in standing and progressive wave field. The model has been successfully used to interpret and quantify experimental observations in liquid/gas, trans-critical/super-critical and gas/gas configurations and showed that the Helmholtz number α characterizing the acoustic field and the density ratio η characterizing the two media are two parameters of importance. The major conclusions are that the observed phenomena can be interpreted as resulting from non-linear acoustics, the key feature being the density ratio. It is claimed that the layer separating the two media, seen as an interface, does not need to be restricted only to a liquid/gas interface

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42

FERRETO, HELIO F. R. "Estudo da sintese copolimero olefínico à base de politetrafluoroetileno (PTFE) por meio da enxertia induzida por radiação gama." reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11420.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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43

Kim, Julian. "EFFECT OF RADIATION THERAPY ON SURVIVAL IN PATIENTS WITH RESECTED MERKEL CELL CARCINOMA: A POPULATION-BASED ANALYSIS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1278471897.

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44

Chapa, Matthew R. "Analysis of 3D silicon pixel vertex detector damage effects due to radiation levels present in the LHC at CERN." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76932.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2012.
"June 2012." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 45).
In high energy physics experiments, very high precision tracking of charged particles is needed. Solid state detectors achieve the high precision necessary to provide track and vertex reconstruction of the particles that traverse them, but tracking performance begins to deteriorate at fluxes of radiation around 10¹⁴ - 10¹⁵ hadrons/cm 2. These radiation levels are congruent with those experienced by the ATLAS pixel detector, the inner most part of the ATLAS tracking system, which is vital to track and vertex reconstruction. During the planned shut-down of the Large Hadron Collider (LHC) in 2013-2014, the energy and luminosity of the LHC will both be increased. The current pixel detector has begun to suffer deterioration of performance, so the ATLAS Collaboration has initiated an upgrade to take place during the scheduled shut-down beginning in 2013, the Insertable B-Layer (IBL). The IBL will be assembled and placed in between a reduced diameter beam pipe and the current pixel detector, acting as the fourth layer of the ATLAS inner detector. The pixel sensors of the IBL will have to sustain a radiation dose of 5 * 10¹⁵neq/cm². Two sensor technologies are being considered for the IBL upgrade: planar n-in-p silicon pixel sensors and 3D double sided n-in-p pixel sensors. Research of both these technologies is being done by the IFAE in collaboration with CNM-Barcelona. To cope with the increased data rate after the LHC upgrade, a new front-end chip has also been produced, the FE-14 front-end chip. Test results and data analysis from five different 3D pixel sensor devices, all fabricated at CNM-Barcelona were done. Evaluation of these technologies and the test results of irradiated 3D pixel sensor devices are carried out in this thesis.
by Matthew R. Chapa.
S.B.

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45

OLIVEIRA, JOSELENE de. "Determinacao dos niveis de radioatividade natural em aguas utilizadas para abastecimento publico no Estado de Sao Paulo .Vol. 2." reponame:Repositório Institucional do IPEN, 1998. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10699.

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Tese (Doutoramento) - IPEN Apendices
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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46

Bernier, Marie-Odile. "Mise en place d'une cohorte d'enfants exposés au scanner et analyse du risque de cancer radio-induit." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066744/document.

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L'exposition médicale diagnostique aux rayonnements ionisants représente environ 40% de l'exposition totale aux radiations en France. L'utilisation du scanner, beaucoup plus irradiant que l'imagerie conventionnelle, ne cesse de progresser, y compris chez les enfants, dont la radiosensibilité est supérieure à celle des adultes. Plusieurs études récentes sont en faveur d'une augmentation du risque de leucémie et de tumeur cérébrale après exposition au scanner dans l'enfance. Une cohorte nationale multicentrique a été mise en place à l'IRSN depuis 2009 incluant plus de 108 137 enfants soumis à un ou plusieurs scanners avant l'âge de 10 ans sur la période 2000-2010 dans 23 services de radiologie pédiatriques de CHU, répartis sur l'ensemble du territoire. L'estimation des doses reçues au niveau des principaux organes a été faite en fonction des protocoles utilisés. La grande variabilité des doses selon les services témoigne de la nécessité d'optimisation des protocoles. Près de 3% des enfants de la cohorte présentaient un facteur de prédisposition aux cancers étudiés. Le croisement de la cohorte avec le registre national des cancers pédiatriques a identifié 106 cas incidents de cancer, dont 22 tumeurs cérébrales et 17 leucémies. Chez les enfants sans facteur de prédisposition, un excès de risque positif mais non significatif était observé pour la leucémie et les tumeurs cérébrales en fonction de la dose, similaire à celui observé pour la population d'étude dans son ensemble. Chez les enfants avec un facteur de prédisposition au cancer, le risque diminuait, possiblement en lien avec une mortalité précoce augmentée entrainant un déficit de risque de cancer radio-induit à plus long terme. Le projet européen EPI-CT inclut 9 cohortes nationales, dont la cohorte française et regroupera plus d’un million d’enfants exposés au scanner. L’analyse conjointe de ces données permettra d’apporter prochainement des résultats complémentaires sur ce sujet
Medical diagnostic exposure to ionizing radiation represents about 40% of the total annual radiation exposure in France. The CT scans, which represent only 5% of the total number of X-rays examinations, account for half of the total collective dose associated with medical diagnostic exposure. However, its use continues to grow, including in children, for whom the radio sensitivity is known to be greater than in adults. Several recent studies support an increased risk of leukemia and brain tumors after exposure to CT scan in childhood. A national multicenter cohort was set up at the IRSN since 2009 including 108 137 children subjected to at least one CT scans before the age of 10 during the 2000 to 2013 period in 23 French University hospital’s pediatric radiology departments. Children's exposure was assessed based on radiological protocols. It was observed high variability of doses according to the participant departments, reflecting the need for protocol optimization. Moreover, children with predisposing factor for studied cancers represented 3% of the study population, a percentage well above that observed in the general population. The linkage of the cohort with the National Register of pediatric cancers identified 106 incident cases of cancer in the cohort, 22 brain tumors and 17 leukemias. For children without predisposing factor, it was observed a non-significant excess risk of cancer according to the received dose, similar to that observed for the whole study population. For children with predisposing factor to cancer, the risk decreased without reaching significance, possibly linked to earlier non-cancer mortality in this group and then to a lower risk to develop later radiation induced cancer. The European project EPI-CT, which includes 9 national cohorts (including the French cohort), will include more than one million children and then will bring further results on this topic

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47

Andersson, Lucas. "Shadow effects in open cross-sections : An analysis of steel temperatures with COMSOL Multiphysics, TASEF and Eurocode." Thesis, Luleå tekniska universitet, Byggkonstruktion och brand, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70086.

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Steel is a material commonly used in various constructions such as high-rise buildings, sport arenas, ships etc. Steel is a versatile building material due to its isotropic characteristics, e.g. both high tensile- and compressive strength. This allows steel to be formed into open section profiles which reduces material usage but simultaneously allows the tensile- and compressive stress resistance to be high in directions were loads are applied. Although steel has a high stress resistance its sensitivity to fire is larger than other building materials due to its high thermal conductivity. The strength of the material is reduced at higher temperatures and thereby makes the dimensioning of beams in fire cases vital in fire safety design of structural elements. An aspect to consider when dimensioning open section building elements in steel is the shadow effect. The shadow effect is the result of the open cross-section geometrical shape of beams and columns, e.g. H-profiles. The interior of the profile is screened from thermal radiation caused by fire which makes the characteristics of the thermal exposure different from closed cross-section profiles. A common way to estimate the temperatures of steel after a certain time of fire exposure is to use numerical calculations described in Eurocode. In these calculations the shadow effect is applied as a reduction of the total heat exchange, i.e. both convection and thermal radiation, from the fire exposure. A more realistic approach is to separate these boundary conditions and treat them as independent quantities. Wickström (2001) argues that a void is created within the flanges and that reduction factor thereby only should be applied to the radiative part of the total heat exchange, acting as a reduction of surface emissivity within the profile. This, since the convection is not affected by the shadow effect. Wickströms (2001) suggestion of application has been investigated in this thesis and has showed a better correlation than the approach suggested in Eurocode when compared to experimental tests. Shadow effects calculated on the premises of separated boundary conditions for the total heat exchange has of yet only been investigated in detail with TASEF+-simulations, but these simulations predicts steel temperatures with satisfactory results. It is possible to reproduce a similar setup in the program COMSOL Multiphysics in two-dimensional simulations, and further three-dimensional simulations. This possibility has been investigated in this thesis. COMSOL Multiphysics has proven to be an adequate tool when it comes to simulate fire exposure on slender steel beam with shadow effects considered. Both three- and two-dimensional models produced simulation results correlating well to simulations conducted in TASEF. Additionally, adequate correlations with experimental tests were obtained for COMSOL Multiphysics as well. Further work regarding fire simulations with the utilisation of COMSOL Multiphysics is thereby suggested.

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48

COELHO, JOAQUIM M. S. "Serrapilheira aplicada como biomonitor na avaliação do bosque urbano do Instituto de Pesquisas Energéticas e Nucleares, São Paulo, SP." reponame:Repositório Institucional do IPEN, 2012. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10108.

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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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49

BLAY, CLAUDIA C. "Analise comparativa da reducao bacteriana com irradiacao do laser Er:YAG ou ponta montada em alta rotacao apos remocao de tecido cariado em dentina: estudo in anima nobile." reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10940.

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Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia)
IPEN/D-MPLO
Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo

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50

REGO, MARIA E. de M. "Gestão dos rejeitos radioativos gerados na produção de 99Mo por fissão nuclear." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10584.

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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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