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

Système de protections novateur et distribué pour les réseaux Moyenne Tension du futur

Jecu, Cristian 16 September 2011 (has links) (PDF)
Ce travail est lié au système de protection des réseaux de distribution. Les réseaux radiaux dedistribution peuvent être protégés simplement par une protection placée en tête du départ. Maisl'exploitation future des réseaux de distribution, qui se transforment en réseaux intelligents,flexibles et adaptatifs, va sûrement nécessiter une protégeabilité plus complexe. Parconséquent, un nouveau plan de protection pourrait être nécessaire afin d'augmenter la fiabilitédu réseau de distribution et le taux de productions décentralisées. Il pourrait inclure plusieursprotections déployées sur un départ. Le but principal de ce travail est d'étudier comment lesprotections pourraient agir (sur quel genre de grandeurs les protections reposeront, quellecoordination faut-il choisir) et d'analyser les limites de ces nouvelles protections. En déployantplusieurs protections qui divisent le départ en des zones plus petites, le plan de protectionproposé, reposant sur une formulation modifié et optimisée, proche de celle des protections dedistance classiques, déconnectera ainsi moins de consommateurs et de producteurs lors del'apparition de défauts. Cela devrait réduire le temps de coupures brèves et de diminuerl'énergie non fournie. Ce manuscrit présente une solution pour les réseaux HTA radiaux faceaux défauts monophasés.
12

Caractérisation et valorisation de protections solaires pour la conception de bâtiments : analyse expérimentale et propositions de modélisations / Characterization and enhancement of shading solar devices in order in the context of solar building design : experimental analysis and modelling proposals

Dugué, Antoine 18 October 2013 (has links)
Lors d’une démarche de modélisation énergétique d’un bâtiment, la prise en compte de l’enveloppe solaire reste souvent imprécise. L’objet du travail présenté ici est la description détaillée de solutions de protections solaires, induisant un tirage thermique (bardage, store), dans un objectif de modélisation et de valorisation pour répondre aux besoins d’industriels du secteur ; la caractérisation des performances permet alors d’assister la maitrise d’œuvre en phase conception.La mise en place d’une plateforme expérimentale – mur exposé sud muni d’une protection solaire devant lame d’air – a permis la mesure de températures d’airs et d’éléments solides présents dans le système, de vitesses d’écoulement dans la lame d’air ouverte, et du flux radiatif incident. Deux types de bardage bois, un type de store et un type de métal déployé ont été considérés.Parallèlement, un modèle 1D amélioré de transfert de chaleur dans le système étudié est développé. Trois familles de modèle de convection dans la lame d’air sont identifiées, présentées et intégrées dans le modèle global. La description de l’écoulement dans la lame d’air est retenue à partir d’analyses des résultats expérimentaux.Un modèle simplifié d’intégration de tels systèmes de protections solaires dans des plateformes de simulation thermique de bâtiments est proposé, basé sur la paramétrisation des sollicitations extérieures par le facteur solaire. La méthode de calcul du facteur solaire est présentée. Le caractère intrinsèque facteur solaire et son intérêt sont discutés notamment à partir d’analyse de sensibilités. / During the design process of a building, the energetic modelling of the solar envelop is often imprecise. The purpose of the present work is the detailed description of solar shading devices that induce a chimney effect such as claddings or blinds, which would allow their promotion in order to meet the industrial needs of the sector. An experimental platform – south facing wall with a shading solar device that define an air gap – has been set up and allow the measurement of temperatures, air flows in the ventilated air gap, and the incident solar radiation. Two different wooden claddings, one type of blinds and one type of expanded metal were considered.A 1D model has been developed by considering precisely the heat transfers in the system. Three families of convection model are identified, presented and integrated in the overall model. The description of the airflow in the air gap is chosen from analysis of the experimental results.A simplified model that allows the integration of such solar shading devices in a building simulation platform has been developed; it is based on the parameterization of external solicitations as function of the shading device properties. The calculation method of the solar factor is presented. The intrinsic nature of the solar factor is then discussed using sensibility analysis.
13

Protection of indigenous peoples in Africa: the case of the batwa in Rwanda

Nkurunziza, Venant January 2013 (has links)
Magister Legum - LLM
14

Assessment of head injury risk caused by impact using finite element models

Palomar Toledano, Marta 20 January 2020 (has links)
[ES] Las cargas de impacto son la fuente primaria de lesiones en la cabeza y pueden resultar en un rango de traumatismo desde leve hasta severo. Debido a la existencia de múltiples entornos en los que se pueden desencadenar lesiones por impacto (accidentes automovilísticos, deportes, caídas accidentales, violencia), éstas pueden afectar potencialmente a toda la población independientemente de su estado de salud. Pese al creciente esfuerzo en investigación para comprender la biomecánica de las lesiones por traumatismo en la cabeza, todavía no es del todo posible realizar predicciones precisas ni prevenir estos eventos. En esta Tesis, se han estudiado algunos aspectos del comportamiento ante impacto de los diferentes tejidos biológicos involucrados mediante el desarrollo de un modelo numérico de cabeza humana a partir de imágenes de tomografía computerizada (TAC). Se han realizado simulaciones en elementos finitos (EF) de ensayos experimentales de la literatura con el fin de validar el modelo numérico desarrollado, estableciendo unas propiedades mecánicas adecuadas para cada uno de sus constituyentes. De esta manera se puede adquirir una predicción adecuada del riesgo de sufrir daños. Parte de esta Tesis se centra en el entorno balístico, específicamente en cascos de combate antibalas, los cuales son susceptibles de causar traumatismo craneoencefálico debido a la elevada deformación que sufren durante el impacto. Previamente al estudio de estos fenómenos de alta velocidad, se han realizado ensayos experimentales y numéricos para caracterizar la respuesta mecánica de algunos materiales compuestos ante impacto de baja velocidad. Al principio de esta Tesis se ha realizado una revisión del estado del arte acerca de los criterios existentes para cuantificar el trauma craneoencefálico.Este es un aspecto clave para las simulaciones numéricas, ya que la idoneidad de algunos de estos criterios para la predicción de lesiones cerebrales todavía es un debate abierto. Mediante EF se han realizado simulaciones de impactos balísticos en una cabeza protegida con un casco de combate. Mediante la posterior aplicación de diferentes criterios de daño sobre los resultados obtenidos se ha evaluado el nivel de protección que aseguran los protocolos de aceptación de cascos de combate, así como las estrategias para determinar su tallaje. Se ha demostrado que las normativas existentes para cascos de combate son capaces de mitigar algunos mecanismos de trauma pero no logran prevenir otros como los gradientes de presión intracraneales. Además, se ha demostrado que algunas de las estrategias de tallaje más comúnmente adoptadas por los fabricantes, como producir un solo tamaño de calota, deberían ser reconsideradas ya que existe un mayor riesgo de traumatismo cuando la distancia entre la cabeza y la calota del casco no es suficiente. Siguiendo la línea de protecciones personales, algunos de los materiales compuestos comúnmente empleados en la industria armamentística se han combinado para crear distintas configuraciones de calota para optimizar la relación entre peso del casco y protección para la cabeza. Materiales ligeros como el UHMWPE han resultado en un comportamiento menos eficiente que el de los apilados de tejido de aramida a la hora de limitar la BFD (deformación máxima en la calota del casco en la zona de impacto). Hacia el final de la Tesis se presenta un modelo numérico de cabeza humana detallado, que incluye treinta y tres de las estructuras anatómicas principales. Dicho modelo se ha desarrollado para la simulación de un accidente ecuestre en el que aparecen múltiples lesiones craneoencefálicas. Principalmente, se pretende establecer un criterio mecánico para predecir el hematoma subdural (HS) basado en la ruptura de los vasos sanguíneos intracraneales. Se ha propuesto un valor umbral de ruptura en tensiones de 3.5 MPa, pero tanto este límite como la localización del vaso dañado son altamen / [CAT] Les càrregues d'impacte son la font primària de lesions al cap i poden resultar en un rang de severitat des de lleu a greu. Degut als múltiples entorns en que poden desencadenar-se lesions per impacte (accidents automobilístics, esports, caigudes accidentals, violència), aquestes poden afectar potencialment a tota la població independentment del seu estat de salut. Malgrat el creixent esforç en investigació per comprendre la biomecànica de les lesions per traumatisme al cap, encara no és del tot possible realitzar prediccions precises ni prevenir aquestos esdeveniments. En aquesta Tesi, s'han estudiat alguns aspectes del comportament a impacte dels diferents teixits biològics involucrats mitjançant el desenvolupament d'un model numèric de cap humà a partir d'imatges de tomografia computeritzada (TAC). S'han realitzat simulacions en elements finits (EF) d'assajos experimentals de la literatura amb la finalitat de validar el model numèric desenvolupat, establint unes propietats mecàniques adequades per a cadascun dels seus constituents. D'aquesta manera es pot aconseguir una predicció del risc de sofrir danys traumàtics. Part d'aquesta Tesi es centra en l'entorn balístic, específicament en cascs de combat antibales, els quals són susceptibles de causar traumatisme degut a l'elevada deformació que sofrixen durant l'impacte. Previament a l'estudi d'aquests fenòmens d'alta velocitat, s'han realitzat assajos experimentals i numèrics per a caracteritzar la resposta mecànica d'alguns materials compostos en condicions d'impacte a baixa velocitat. Al començament d'aquesta Tesi s'ha realitzat una revisió de l'estat de l'art sobre els criteris existents per quantificar el trauma cranioencefàlic. Aquest és un aspecte clau per a les simulacions numèriques, ja que l'utilitat d'alguns d'aquestos criteris per a la predicció de lesions cerebrals és encara un debat obert. Mitjançant EF s'han realitzat simulacions numèriques d'impactes balístics en un cap protegit amb un casc de combat. Gràcies a la posterior aplicació de diferents criteris de dany sobre els resultats obtinguts s'ha evaluat el nivell de protecció que asseguren els protocols d'acceptació de cascs de combat, així com les estratègies per a determinar les seues talles. S'ha demostrat que les normatives existents són capaces de mitigar alguns mecanismes de trauma però no aconseguixen prevenir altres com els gradients de pressions intracranials. A més, s'ha demostrat que algunes estratègies per determinar les talles més comunament adoptades pels fabricants (com produir només un tamany de calota i adaptar el gruix de les escumes interiors a les diferents dimensions dels subjectes) haurien de ser reconsiderades ja que existeix un major risc de traumatisme quan la distància entre el cap i la calota del casc no és suficient. Seguint la línia de proteccions personals, alguns dels materials compostos comunament utilitzats en la indústria de l'armament s'han combinat per a crear distintes possibles configuracions de calota amb la finalitat d'optimitzar la relació entre pes i protecció. Materials lleugers com l'UHMWPE han resultat en un comportament menys eficient que el d'apilats de teixit d'aramida a l'hora de limitar la BFD (deformació màxima a la calota del casc a la zona d'impacte). Cap al final de la Tesi es presenta un model numèric detallat de cap humà, que inclou trenta-tres de les estructures anatòmiques principals. Aquest model s'ha desenvolupat per a la simulació d'un accident eqüestre en el qual apareixen múltiples lesions cranioencefàliques. Principalment, es pretén establir un criteri mecànic per a la predicció de l'hematoma subdural (HS) basat en la ruptura dels vasos sanguinis intracranials. S'ha proposat un valor umbral de ruptura en tensions de 3.5 MPa, pero tant aquest límit com la ubicació del vas danyat són altament dependents de l'anatomia específica de cada subjecte. / [EN] Impact loading is the primary source of head injuries and can result in a range of trauma from mild to severe. Because of the multiple environments in which impact-related injuries can take place (automotive accidents, sports, accidental falls, violence), they can potentially affect the entire population regardless of their health conditions. Despite the increasing research effort on the understanding of head impact biomechanics, accurate prediction and prevention of traumatic injuries has not been completely achieved. In this Thesis, some aspects of the impact behaviour of the different biological tissues involved have been analysed through the development of a numerical human head model from Computed Tomography (CT) images. FE simulations of experimental tests from the literature have been performed and enhanced the validation of the head model through the establishment of proper material laws for its constituents, which enable adequate prediction of injury risks. Part of this Thesis focuses on the ballistic environment, especifically in bulletproof composite helmets, which are susceptible to cause blunt injuries to the head because of their large deformation during impact. Prior to the study of these high-speed impacts, experimental tests and finite element (FE) models have been performed to characterise the mechanical response of composite materials subjected to low velocity impact. The implementation of a continuum damage mechanics approach coupled to a Hashin failure criterion and surface-to-surface cohesive relations to the numerical model provided a good matching with the impact behaviour obtained experimentally, capturing the principal damage mechanisms. A review of the head injury criteria currently available in the literature has been performed at the beginning of this Thesis. This is a key issue for the numerical simulations, as the suitability of some criteria to predict head injuries is still an open question. Numerical simulation of ballistic impacts on a human head protected with a combat helmet has been conducted employing explicit FE analysis. The level of protection ensured by helmet acceptance protocols as well as their sizing strategies have been studied and discussed by means of the application of different mechanical-based head injury criteria. It has been demonstrated that current helmet testing standards do mitigate some specific forms of head trauma but fail to prevent other injury mechanisms such as the intracranial pressure gradients within the skull. Furthermore, it has been demonstrated that some well-established helmet sizing policies like manufacturing one single composite shell and adapting the thickness of the interior pads to the different head dimensions should be reconsidered, as there is a great risk of head injury when the distance between the head and the helmet shell (stand-off distance) is not sufficient. Following the line of personal protections, some composite materials commonly employed in the soft body armour industry have been combined into different helmet shells configurations to optimise the ratio of weight-to-head protection. Light materials like UHMWPE appear to be less efficient than integral woven-aramid lay-ups in the limitation of the backface deformation (BFD), the maximum deformation sustained by the helmet at the impact site. A detailed head numerical model including thirty-three of its main anatomical structures has been developed for the simulation of an equestrian accident that resulted in many head injuries. Above all, the establishment of a mechanical criterion for the prediction of subdural hematona (SDH) based on the rupture of the head blood vessels is intended. A stress threshold for vein rupture has been set on 3.5 MPa, but both this limit and the location of vessel failure are highly dependent on the specific anatomy of the subject's vascularity. / Palomar Toledano, M. (2019). Assessment of head injury risk caused by impact using finite element models [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/135254 / TESIS
15

New Surveillance Technologies and the Invasion of Privacy Rights

Simsek, Yilmaz 08 1900 (has links)
Definition of privacy has changed by the changes and improvements in information and surveillance technologies. These changes and improvement need new legal decisions for new kinds of privacy invasions. This study explores the scope of privacy right, particularly when a technological surveillance has occurred by law enforcement agencies. It focuses in particular on increasing law enforcements' surveillance technologies and devices that have the potential to impact citizens' information privacy. These increasing changes in surveillance technologies have important implications both for law enforcements and citizens. This study also discusses increasing law enforcement surveillance for the public's security, changes of the laws that allow law enforcements to use new surveillance powers as a war on terrorism, and the citizens concerns of information privacy. A particular attention is given to the recent public opinion surveys which show citizens' increasing privacy concerns. Finally, a set of recommendations to figure out security-privacy debate and reduce the privacy concerns of the citizens is offered.
16

BARNMORSKORS HANDLÄGGNING I ATT FÖREBYGGA UPPKOMSTEN AV PERINEALBRISTNINGAR : En webbaserad enkätundersökning

Nilsson, Alva, Lejerdal, Ronja January 2020 (has links)
Syfte: Att kartlägga hur barnmorskor arbetar för att förebygga uppkomsten av perinealbristningar i samband med förlossning. Metod: Kvantitativ tvärsnittsstudie där data samlades in genom en webbaserad enkätundersökning och sammanställdes med deskriptiv statistik. Resultat: Totalt deltog 86 barnmorskor, som grupperades om de arbetat ≤7 år eller >7 år. Medelvärdet för antal verksamma år var tre år (M=2,97) för gruppen ≤7 år respektive 18 år (M=18,05) för gruppen >7 år. Barnmorskorna som arbetat ≤7 år ansåg att hög arbetsbelastning påverkade uppkomsten av perinealbristningar och att omsorgsfull närvaro och c greppet var faktorer som motverkade uppkomsten av perinealbristningar. Barnmorskorna som arbetat >7 år följde PM/riktlinjer och förberedde inte kvinnorna med krystningssamtal i början av förlossningen. Båda grupperna använde norska handgreppet och majoriteten höjde barnets huvud vid framfödandet. Slutsatser: Barnmorskor använde ett handgrepp som inte var baserat på evidens eller praktisk erfarenhet. Barnmorskor med längre yrkeserfarenhet förberedde inte kvinnor i början av förlossningen, detta kan ses som bristande empowerment eller att barnmorskor med längre yrkeserfarenhet har lättare att göra en individuell bedömning. Barnmorskor med kortare yrkeserfarenhet ansåg att forcerad förlossning påverkade uppkomsten av perinealbrisningar. Barnmorskor vill ha mer utrymme åt kunskapsutbildning och lära av varandra, vilket kan stärka barnmorskors empowerment. / Aim: Investigate how midwives work to protect perineal tears during labour. Method: Quantitative cross-sectional study, data were collected through a webbased survey and compiled with descriptive statistics. Result: Total of 86 midwives participated, the mean value of active years as midwives in group ≤7 years was (M = 2,97) years. In group >7 years the mean value was (M = 18,05) years. Midwives ≤7 years considered high workload affected the onset of perineal tears and careful attendance and c grip were factors that counteracted of perineal tears. Midwives >7 years followed PM/guidelines and did not prepare women at beginning of labour. Midwives in both groups used the Norwegian hand grip and the majority of midwives raised the baby’s head during delivery. Conclusions: Midwives used a non-evidence based handgrip or practical experience. Midwives with longer experience did not prepare women at the beginning of labour, this can be seen as a lack of empowerment or that midwives with longer experience have easier to make an individual assessment. Midwives with shorter experience considered that forced delivery affected the onset of perineal tears. Midwives want more knowledge and learning from colleagues which can strengthen midwives empowerment.
17

LET’S SELL DRUGS : How the home-State of an investment can upset investment protections in the cannabis industry

Barba Radanovich, José Miguel January 2022 (has links)
Recently many States have legalised the production and retail of recreational cannabis, which is already a big business worldwide, and therefore, thoroughly attractive to international investors who would – reasonably – seek to develop their business in cannabis-friendly jurisdictions but, more so than many investments, this one carries with it a certain risk: Many influential and capital-exporting states are reticent to legalise cannabis for themselves and many times even criminalise any and all cannabis-related activities.  This work uses this dilema to explore the influence of the home-State of the investment on the legality of an investment, and question the uniletarality of the obligations derived from "Free Movement of Liquid Assets" or "repatriation" clauses, arguing that there is a multilateral obligation to protect the movement of investments' returns and that home-States to the investor must fulfill it by not impeding or upseting the repatriation of liquid assets.
18

Souběh autorskoprávní a známkové ochrany / Convergence of Copyright and Trademark Protection

Holub, Lukáš January 2016 (has links)
Convergence of Copyright and Trademark Protection Key Words: Copyright, Trademark, Protection, Convergence Abstract: The thesis analyzes the concept of copyright and trademark protection in Czech law and the consequences of their simultaneous operation. The aim is to determine whether the existing legislation responds the current trends and demands in our society, where business and arts are becoming interconnected and where the boundaries between those disciplines are blurred. Both protections are initially assigned to theoretical context of legal branches of intellectual property and intangible property. The author also deals with current conception of ownership in Civil Code. Following chapters are based on the principles of civil (continental) law concepts of copyright law and industrial property law established in this part. Subsequently the regulation of copyright protection and trademark protection is discussed in two separate chapters. Those chapters are divided into identical sub-chapters to highlight similarities and differences of both legal institutes. The focus is on subjects of both protections, their beneficiaries, formation, content, duration, means, limitations, international context and the issues of licensing. In the chapter devoted to convergence, various situations which might occur...
19

Implantations cryptographiques sécurisées et outils d’aide à la validation des contremesures contre les attaques par canaux cachés

Thuillet, Céline 30 March 2012 (has links)
Depuis plusieurs années, les composants dédiés à la sécurité comme les cartes à puce sont soumises à des attaques dites par canaux cachés. Ces attaques permettent d'exhiber les secrets en analysant des caractéristiques physiques comme la consommation du composant ou encore son temps d'exécution. Dans le cadre de cette thèse, deux contremesures ont été réalisées et appliquées à l'AES (algorithme de chiffrement symétrique). De plus, afin d'aider les développements futurs des contremesures et la validation de celles-ci, un simulateur a été développé. Il permet de réaliser des attaques grâce à un modèle de consommation défini dans les phases amont de développement. Enfin, j'ai pu participer aux groupes de travail qui ont proposé Shabal à la compétition SHA-3, qui vise à définir un nouveau standard pour les fonctions de hachage. Des implantations matérielles ont été réalisées par la suite. / For several years, the security components such as smart cards are subject to side channel attacks. These attacks allow to exhibit secrets by analyzing the physical characteristics such as power consumption or execution time. As part of this thesis, two countermeasures were carried out and applied to the AES (symmetric cipher). In addition, to help future development of countermeasures and their validation, a simulator was developed. It realizes attacks using a power consumption model defined in the early phases of development. Finally, I participated in working groups that have proposed Shabal to SHA-3 competition, which aims to define a new standard for hash functions. Hardware implementations have been made thereafter.
20

Avaliação do desempenho térmico de brises transparentes: ensaio em células-teste / Evaluation thermal performance of transparent solar protections: measurements in test-cells

Miana, Anna Christina 09 December 2005 (has links)
O objetivo desta pesquisa foi avaliar o desempenho térmico de brises transparentes, por meio de medidas em células-teste construídas em escala 1:1, na cidade de Campinas, São Paulo. Trata-se de um estudo que faz avaliação comparativa das temperaturas internas e superficiais dos brises e do vidro da janela em seis células-teste, quatro delas protegidas com brises transparentes horizontais e verticais combinados, constituídos por vidros, outra protegida com brise-soleil metálico horizontal e uma sem dispositivo de proteção solar, sendo esta considerada de referência. Foram selecionados quatro tipos de vidro com diferentes características ópticas: vidro float comum incolor, vidro impresso mini-boreal, vidro float comum azul e vidro refletivo metalizado a vácuo prata médio. Foi possível concluir que os brises de vidro refletivo prata, float azul e impresso possuem um desempenho térmico similar entre si e ao brise metálico estudado, e que o brise de vidro float incolor não apresenta um resultado de desempenho térmico satisfatório. Com relação aos procedimentos de medidas de campo, foram verificadas as modificações necessárias, para trabalhos futuros que tenham o mesmo objetivo dessa pesquisa, ou similares a esse. Além da avaliação do desempenho térmico, foi também iniciada uma avaliação do desempenho luminoso dos brises. Por meio das medidas dos níveis de iluminação natural dentro das células-teste constatou-se que o brise de vidro impresso apresentou um ótimo desempenho luminoso e que o brise de vidro refletivo prata reduziu significativamente a iluminância dentro da célula-teste, obtendo um desempenho luminoso inferior até mesmo ao brise metálico / This research intended to evaluate thermal performance of transparent solar protections using measurements in full scale test cells, located in the city of Campinas, São Paulo, Brazil. Surface (window and shading device) and internal air temperatures were compared for six test cells. One of them was unprotected, for reference purposes, another was obstructed with a metallic shading device and the other four had transparent glass horizontal and vertical shades installed. Four different types of glass with different optical properties were selected: float clear glass, mini-boreal printed glass, float blue glass and metallic silver reflective glass. The results of the thermal appraisal showed that silver reflective glass, float blue and printed glass shadings achieved similar performance, not very different to the ones obtained for the metallic shading device. Therefore the float clear glass shading did not attain a satisfactory result. The field measurements procedures were also evaluated and test cells characteristics problems were identified, in order to suggest changes for future research in this area. This research began to evaluate light performance of the same solar protections. For light performance evaluation were measured the daylight in the center of each test cell and outside. It was concluded that printed glass shadings presented very good results and silver reflective glass reduced the daylight inside the test cell

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