Dans de nombreuses applications, des paquets d’électrons relativistes sub-ps sont requis : Accélération laser-plasma, Lasers à électrons libres, Génération de rayonnement THz intense, Etude des phénomènes ultra-rapides dans la matière… L’aspect court des paquets et la nécessité d’un fort courant crête pour les applications impliquent de fortes forces de charge d’espace conduisant à une dégradation des propriétés du faisceau, telle que son émittance transverse et sa longueur. La principale difficulté est de caractériser, modéliser et prendre en compte ces effets. Ma thèse s’inscrit dans ce cadre à travers l’étude de la dynamique et des diagnostics associés à ces paquets courts. Le chapitre 2 rassemble des mesures de plusieurs propriétés du faisceau : charge, émittance transverse et longueur. L’originalité de mon travail réside dans l’utilisation de méthodes simples, des points de vues théoriques et technologiques. Ces méthodes, plus adaptées pour des faisceaux moins extrêmes, permettent néanmoins d’obtenir de très bons résultats. J’ai en particulier développé une méthode de mesure de charge à partir de la mesure de l’intensité lumineuse émise par un écran scintillant suite à l’interaction avec le faisceau. Cette méthode permet de mesurer précisément des charges inférieures à 100 fC, ce qui surpasse les capacités des diagnostics classiques (ICT et Coupe de Faraday) limités au picocoulomb à cause du bruit électronique. Cette méthode est utile, du fait que les paquets courts sont souvent faiblement chargés pour limiter l’effet des forces de charge d’espace. J’ai aussi adapté des méthodes multiparamétriques pour mesurer l’émittance transverse et la longueur des paquets d’électrons. Ces méthodes indirectes permettent de déterminer ces propriétés à partir de la mesure d’autres propriétés plus accessibles : les dimensions transverses pour l’émittance et la dispersion en énergie pour la longueur. La mesure de longueur (méthode des 3 phases) donne de très bons résultats, puisqu’elle permet de mesurer avec une précision meilleure que 10% des longueurs rms inférieures à la picoseconde. La mesure d’émittance sans prise en compte des forces de charge d’espace donne des résultats mitigés, puisque la précision varie de 20% (méthode des 3 gradients) à plus de 100% (méthode des 3 écrans). Une amélioration significative de la précision, jusqu’à un facteur 5, peut être obtenue en prenant en compte les forces de charge d’espace via une équation d’enveloppe, ce qui constitue l’originalité de mon travail. Le chapitre 3 consiste en une comparaison des propriétés des paquets courts d’électrons, unique ou longitudinalement modulé, générés par trois méthodes différentes : Utilisation d’une impulsion laser courte ou longitudinalement modulée dans un canon RF ; Compression magnétique dans une chicane ; Compression RF dans une structure accélératrice (Velocity Bunching). J’ai en particulier montré que, à charge égale, la génération de paquets courts via une impulsion laser courte dans un canon RF est désavantageuse, des points de vue de la longueur et de l’émittance transverse du faisceau, par rapport à la compression magnétique RF d’un paquet déjà accéléré. Cela est expliqué par les forces de charge d’espace plus importantes juste après l’émission du faisceau par la photocathode. Il est également consacré au développement et au test de modèles analytiques de la dynamique longitudinale des faisceaux. J’ai développé une matrice de transfert longitudinale pour un canon RF, en partant du modèle de K. J. Kim. Ce modèle a été comparé avec plusieurs mesures effectuées à PITZ et PHIL et a prouvé être précis sur les aspects énergétiques et temporels, mais pas sur l’aspect de la dispersion en énergie. J’ai également développé un modèle analytique du phénomène de velocity bunching dans des structures accélératrices à onde progressive, en partant d’un modèle simple développé par P. Piot. / In several applications, quasi-relativistic sub-ps electron bunches are required: Laser-plasma acceleration, Free electron lasers, Generation of intense THz radiation, Study of ultra-fast phenomena in matter… The short nature of the bunch and the necessity of a high peak current for the applications imply strong space-charge forces leading to a degradation of beam properties, as its transverse emittance and duration. The main difficulty is to characterize, model and take into account these effects. My thesis falls within this context through the study of dynamics and diagnostics related to these short bunches, namely whose rms duration is not directly measurable by an electronic method locating the border at a few tens of picoseconds. The chapter 2 consists in the measurements of several properties of these bunches: charge, transverse emittance and duration. The originality of my work is that I use simple methods, both on the theoretical (analytical at maximum) and technological (using only common elements of electron accelerators) point of view. These methods, more suitable for less extreme bunches, allow however obtaining very good results. I especially developed a method of charge measurement from the measurement of the light intensity emitted by a scintillating screen following the interaction with an electron beam. This method allows precisely measuring charges lower than 100fC. This is better than the capabilities of classical diagnostics (ICT and Faraday Cup) limited to the picocoulomb because of electronic noise. This method is useful since the short bunches are often low-charged to minimize the effects of space-charge forces. It will also be used for detectors calibration, which requires low charges. I also adapt multiparametric methods to measure the transverse emittance and duration of electron bunches. These indirect methods allow determining these properties from the measurement of other more accessible properties: the transverse dimensions for the transverse emittance and the energy spread for the duration. The duration measurement (3-phase method) gives very good results, since it allows determining with accuracy better than 10% rms durations lower than one picosecond. The emittance measurement without taking into account the space-charge forces in the modeling gives mixed results, since the accuracy is from 20% (3-gradients method) to more than 100% (3-screens method). A significant accuracy improvement, up to a factor of 5, can be obtained by taking the space-charge forces into account through a beam envelop equation, which constitutes the originality of my work. The chapter 3 consists in the comparison of the properties of short electron beams, single or longitudinally modulated, generated by three different methods: Injection of a short or longitudinally modulated laser pulse in an RF-gun; Magnetic compression in a chicane; RF-compression in an accelerating structure (Velocity Bunching). I particularly shown that, at equal conditions of charge, the generation of short bunches thanks to a short laser pulse driven an RF-gun is disadvantageous, both from the beam duration and transverse emittance point of view, with respect to a magnetic or RF compression of an already accelerated beam. This is explained by the more important space-charge forces just after the beam emission by the photocathode. It also consists in the development and test of analytical models for longitudinal beam dynamics. I developed a longitudinal transfer matrix for RF-gun, starting from a Kim-like model. This model has been compared with several measurements performed at PITZ and PHIL and shown to be accurate on the energy and temporal aspects, but not on the energy spread aspect. I also developed an analytical model of the velocity bunching phenomenon in travelling wave accelerating structures, starting from a simple model developed by P. Piot.

Este trabalho apresenta o quadro da época da chegada dos portugueses no Japão e da sua ação por quase um século em terras nipônicas. A Europa dos séculos XV e XVI era o centro da civilização ocidental, e os portugueses, espanhóis e italianos ocupavam a posição de destaque de controladores e donos do comércio com o oriente médio e a China, via Mar Mediterrâneo e por terra. Os portugueses e os espanhóis, grandes navegadores, ao se aventurarem pelo mar, foram descobrindo e conquistando novas terras e obtendo com isso grandes vantagens de comércio e de divisas. Por outro lado, o Japão, arquipélago isolado e imerso em guerras civis, com muitos conflitos, não tinha a integração de suas unidades, e o desfecho da unificação dos reinos acabou ocorrendo com a ação dos grandes senhores suseranos, os daimyō Oda Nobunaga e Toyotomi Hideyoshi. Os primeiros portugueses - mercadores e missionários - que aportaram no Japão nessa época, por muitos chamada de \"Grandes Navegações\", encontraram o Japão sob o domínio de Nobunaga e Hideyoshi. O primeiro era receptivo, tolerante e pragmático, não se envolvia com a crença, mas servia-se da religião como instrumento para auferir resultados vantajosos desta relação com os portugueses. À primeira vista, o catolicismo foi bem aceito pelas autoridades, por sacerdotes xintoístas e budistas e, consequentemente, também pela comunidade em geral, pois os preceitos do budismo eram julgados coerentes com os \"Dez Mandamentos\" pregados pela Igreja cristã. Posteriormente, com o passar do tempo, os monges budistas e xintoístas sentiram seu espaço ameaçado pela expansão do catolicismo e muitos atritos ocorreram envolvendo adeptos das facções religiosas. As autoridades, sentindo a inconveniência das ações dos católicos e ajudadas pela interferência dos holandeses - que haviam ganho a simpatia dos japoneses -, conseguiram tirar os comerciantes portugueses do caminho, assegurando a exclusividade do comércio juntamente com os chineses, alegando que os ibéricos estariam tramando a tomada do país por meio da disseminação da religião católica. Com isso o governo japonês vetou qualquer atividade religiosa católica no país, promovendo a expulsão de todos os portugueses, espanhóis e italianos, envolvidos ou não com a religião. Apesar de a estada dos portugueses ter sido limitada a 96 anos, este trabalho ressalta o mérito das ações realizadas pelos mercadores e pelos missionários que deixaram um legado importante para os japoneses de então, bem como para as gerações seguintes, servindo de base para outras contribuições que viriam dos holandeses e chineses, que ocuparam o espaço dos retirantes latinos. De todas as contribuições efetuadas pelos portugueses e que influenciaram a cultura japonesa, a que mais impactou na política e na sociedade japonesa foi realmente a introdução das armas de fogo, as espingardas, cujo desdobramento deu outro rumo para a história do Japão. / This thesis presents a state when Portuguese arrived in Japan, and their actions for almost a century in Japanese land. At that time, Europe was the center of occidental civilization and Portuguese, Spanish and Italians were leaders as market controllers and masters of Middle East and China zones, by Mediterranean Ocean and by land. Portuguese and Spanish, great navigators explored the oceans, discovering and conquering new lands obtaining huge benefits in trade and money. At the other hand, Japan, an isolated archipelago and under civil wars with many conflicts, with no integration of their unities, the unification only were be able to be achieved by actions of great lords as Oda Nobunaga and Toyotomi Hideyoshi. When the first Portuguese, merchants and missionaries, ashored Japan, the country was under Nobunaga and Hideyoshi domain, the first one, who welcomed them but not concerning with religion affairs, only shown interests in beneficial gains relating with them. In a first moment, the catholicism was accepted by Government officials and shinto and buddhist priests , consequently also by the people, because it was thought that catholic precepts were coherent with buddhist ones. Lately, buddhist and shinto priests felt a fear with the expansion of catholicism, and troubles started to occur within religion groups. Government officials also feeling the inconvenience of actions of catholic priests and aided by Dutchmen interference, interested in keeping away the Portuguese merchants, gained confidence of Japanese Government officials, alleging that they were attempting to subjugate the people by dissemination of catholicism. Due to that, any catholic religion activity was banned, ending with the expulsion of all Portuguese, Spanish and Italians, missionaries or not. In spite the stay of Portuguese in Japan was limited to 96 years, its showed the merit of works developed by merchants and missionaries, who left an important heritage to Japanese people, as well as for following generations as base for other foreign contributions, as Dutchmen or Chinese. For all contributions made by Portuguese, that so influenced Japanese culture and the most impact caused was really the introduction of firearms that promoted another course of the Japanese History.

Gun violence on college campuses has gained the attention of campus leaders, leading to an active shooter policy and procedure development and implementation. There was little awareness within the campus leadership of a college in the Southeast United States on the college's active shooter policy and procedures. Guided by Coomb's crisis management plan model, the purpose of this case study was to explore how information was provided to students, faculty, and staff regarding how to respond to an active shooter on campus. Purposeful sampling was used to identify 16 participants (6 students, 5 faculty, and 5 administrator/staff) who were interviewed in person. Data analysis included content analysis for the documents and open and axial coding for the interview data, followed by identification of emergent themes. The outcomes included significant variations and inconsistencies among students, faculty, and staff regarding awareness and understanding of how to respond to an active shooter crisis. Overall, students demonstrated the least awareness and understanding. Based on the findings, a project was developed consisting of recommendations to augment the current active shooter procedures and to develop a comprehensive active shooter policy. The results of the study could promote increased awareness, understanding, and preparation for students and employees of technical and community colleges regarding an active shooter policy and procedures, thus increasing safety and confidence on campus.

The Great War was in many ways a conflict defined by technology. The rapid advancements in technology over the decades leading up to 1914 coupled with the outdated tactics employed by all sides created the stalemate of Trench Warfare. Improvements to the existing technology, the addition of new technology, as well as an evolution in tactics led to the breakout, and eventual Allied victory, of 1918. These changes in tactics and technology significantly affected the lives of frontline soldiers. This thesis asks if the tactical and technological changes, in the final two years of the war, were reflected in diaries and memoirs of Canadian soldiers serving at the front. The diaries and memoirs of the soldiers do reflect many of the changes found in the secondary sources. Surprisingly, however, the primary sources often provide more detail about how these weapons were employed by the Germans. Unless the soldier in question was directly involved in their use, or was witnessing a spectacular event, accounts of Canadian artillery, machine gun and poison gas use are often short and lacking in detail.

Esta Tese é composta por dois ensaios, nos quais são apresentados modelos teóricos de Economia do Crime. O primeiro estuda o impacto de políticas de controle de armas sobre o crime através de um modelo teórico de crime e autodefesa com o uso de armas. As principais conclusões são que mudanças nos payoffs geram equilíbrios distintos, além disso, o controle de armas leva a uma redução nos crimes com armas e que estas políticas são mais eficientes quando afetam os custos tanto de criminosos quanto das vítimas. O segundo propõe um modelo dinâmico baseado em opções reais para avaliar a carreira criminosa. No modelo, os indivíduos podem escolher o melhor momento para se engajar no crime (atividade ilegal). Através da calibragem do modelo é possível observar que a opção por uma carreira criminosa depende de um retorno alto na atividade ilegal mesmo quando os indivíduos são neutros ao risco e possuem uma taxa de desconto intertemporal baixa. / This Thesis is composed by two essays, which theoretical models of economics of crime are presented. The first studies the impact of gun control policies on crime trough a theoretical model of crime and self-defense with guns. The main conclusions are that payoffs change generates different equilibriums, besides, gun control implies on a decrease of gun crimes and that such policies are more effective when affects both criminals and victims costs. The former purpose a dynamic model based on real options to evaluate the criminal career. In the model, individuals can choose the best moment to get in crime. Through model calibration is possible to observe that the option for a criminal career depends on a high return in the illegal activity even when individuals are risk neutral and when they have a low time discount.

Made available in DSpace on 2014-10-09T12:50:50Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:24Z (GMT). No. of bitstreams: 1 11097.pdf: 8468953 bytes, checksum: 884442a7a2e945eacad452d3697f2149 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

This thesis describes the basic breeds of work dogs presently used by the Police of the Czech Republic, divides the dogs by their character and psychologic features, and processes the current literature and regulations relating to work dogs training. The thesis summarizes the data collected from 8 Regional Directorates of the Police of the Czech Republic regarding the number of casas when the work dogs were utilized in practice in 2007, 2008 and up to the 3rd quarter of 2009. All the stated information has been processed in the thesis with the aim to elaborate a methodology of training of work dogs intended for guns and ammunition search, and to set the standards for assesment of suitability of individual dogs for training for guns and ammunition search, and for their subsequent utilization in practice. The obtained data were used in the thesis for elaboration of the methodology of work dogs training for guns and ammunition search. While elaborating the methodology it was ascertained thatdespite the existing universal training methodology each dog requires an individual approach with due regard to its physical and mental characteristics. The thesis also includes setting the standards for assesment of suitability of individual dogs for traning for guns and ammunition search, and for their subsequent utilization in practice. This thesis may be used in practice as a methodology of work dogs training for guns and ammunition search in training centres of the Police of the Czech Republic and in individual Special Cynology Groups of the Police of the Czech Republic, and subsequent utilization of trained dogs in practice for protection of citizens.

Esta Tese é composta por dois ensaios, nos quais são apresentados modelos teóricos de Economia do Crime. O primeiro estuda o impacto de políticas de controle de armas sobre o crime através de um modelo teórico de crime e autodefesa com o uso de armas. As principais conclusões são que mudanças nos payoffs geram equilíbrios distintos, além disso, o controle de armas leva a uma redução nos crimes com armas e que estas políticas são mais eficientes quando afetam os custos tanto de criminosos quanto das vítimas. O segundo propõe um modelo dinâmico baseado em opções reais para avaliar a carreira criminosa. No modelo, os indivíduos podem escolher o melhor momento para se engajar no crime (atividade ilegal). Através da calibragem do modelo é possível observar que a opção por uma carreira criminosa depende de um retorno alto na atividade ilegal mesmo quando os indivíduos são neutros ao risco e possuem uma taxa de desconto intertemporal baixa. / This Thesis is composed by two essays, which theoretical models of economics of crime are presented. The first studies the impact of gun control policies on crime trough a theoretical model of crime and self-defense with guns. The main conclusions are that payoffs change generates different equilibriums, besides, gun control implies on a decrease of gun crimes and that such policies are more effective when affects both criminals and victims costs. The former purpose a dynamic model based on real options to evaluate the criminal career. In the model, individuals can choose the best moment to get in crime. Through model calibration is possible to observe that the option for a criminal career depends on a high return in the illegal activity even when individuals are risk neutral and when they have a low time discount.

Esta Tese é composta por dois ensaios, nos quais são apresentados modelos teóricos de Economia do Crime. O primeiro estuda o impacto de políticas de controle de armas sobre o crime através de um modelo teórico de crime e autodefesa com o uso de armas. As principais conclusões são que mudanças nos payoffs geram equilíbrios distintos, além disso, o controle de armas leva a uma redução nos crimes com armas e que estas políticas são mais eficientes quando afetam os custos tanto de criminosos quanto das vítimas. O segundo propõe um modelo dinâmico baseado em opções reais para avaliar a carreira criminosa. No modelo, os indivíduos podem escolher o melhor momento para se engajar no crime (atividade ilegal). Através da calibragem do modelo é possível observar que a opção por uma carreira criminosa depende de um retorno alto na atividade ilegal mesmo quando os indivíduos são neutros ao risco e possuem uma taxa de desconto intertemporal baixa. / This Thesis is composed by two essays, which theoretical models of economics of crime are presented. The first studies the impact of gun control policies on crime trough a theoretical model of crime and self-defense with guns. The main conclusions are that payoffs change generates different equilibriums, besides, gun control implies on a decrease of gun crimes and that such policies are more effective when affects both criminals and victims costs. The former purpose a dynamic model based on real options to evaluate the criminal career. In the model, individuals can choose the best moment to get in crime. Through model calibration is possible to observe that the option for a criminal career depends on a high return in the illegal activity even when individuals are risk neutral and when they have a low time discount.

Made available in DSpace on 2014-10-09T12:50:50Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:24Z (GMT). No. of bitstreams: 1 11097.pdf: 8468953 bytes, checksum: 884442a7a2e945eacad452d3697f2149 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP