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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.
671

Les SARMs (Selective Androgen Receptor Modulators) : une nouvelle famille d'agents anabolisants. Etude des effets zootechniques associés et développement de stratégies analytiques visant la mise en évidence de leur utilisation chez le jeune bovin / SARMs (Selective Androgen Receptor Modulators) : a new class of anabolic agents. Zootechnical effects and analytical strategies to detect their administration in bovines

Cesbron, Noura 04 June 2017 (has links)
De nouveaux composés anabolisants sont devenus accessibles via Internet : les modulateurs spécifiques des récepteurs androgènes (SARMs) actuellement développés pour le traitement des pertes musculaires. L’Ostarine® (MK-2866, GTX-024, enobosarm) en particulier, exerce ses effets sur les muscles squelettiques et ne présente pas d'activité androgénique. Sur la base de son mécanisme d’action et des résultats cliniques préliminaires, ce produit pourrait être utilisé comme promoteur de croissance en élevage bovin. Dans ce contexte, les objectifs de la thèse sont de valider des outils permettant de décrire les effets zootechniques pouvant être induits par l’administration orale d'enobosarm à des bovins et de développer des stratégies analytiques dédiées à la mise en évidence de son utilisation frauduleuse. En comparant animaux contrôles et animaux traités avec l'enobosarm, aucun effet morphologique n'a été mis en évidence en termes de croissance ou de conformation. Il a été ensuite démontré que l'enobosarm et ses principaux métabolites de phase II sont éliminés dans les urines et les fèces à des concentrations permettant leur détection par des techniques analytiques impliquant le couplage chromatographie en phase liquide et spectrométrie de masse. Enfin, une stratégie de type métabolomique conduite sur matrices urinaire et fécale a conduit à la description d’empreintes spécifiques et discriminantes pouvant signer l’administration d'enobosarm. Ce travail de recherche pluridisciplinaire contribue à générer des connaissances sur une nouvelle classe d'anabolisants, permettant par extension de contribuer à garantir au consommateur une sécurité chimique accrue des denrées d’origine animale. / New compounds with anabolic properties have recently become accessible via Internet-based suppliers: selective androgens receptor modulators (SARMs) currently developed for the treatment of chronic diseases with wasting muscle. Ostarine® (MK-2866, GTX-024, enobosarm), in particular, exerts its anabolic effects exclusively on the skeletal muscles and has no androgenic activity. Based on its mechanism of action and clinical preliminary results, this product could potentially be used as a growth promoter in cattle. In this context, the aims of this thesis are to validate tools allowing to describe the zootechnical effects that may be induced by an oral administration of enobosarm in calves and to develop analytical strategies dedicated to highlight its fraudulent use. Following a comparison between control animals and enobosarm treated animals, no morphological effect was visible and measurable in terms of growth and conformation. It was then demonstrated that enobosarm and its main phase II metabolites are eliminated in urine and feces at concentrations allowing their detection with analytical techniques using a liquid chromatography-mass spectrometry coupling. Finally, a metabolomics approach on urine and fecal matrices led to the description of specific and discriminant fingerprints signaling the administration of enobosarm. This multidisciplinary research work helps to generate knowledge on a new class of anabolic substance and therefore contributes to guarantee a more chemically-safe food of animal origin to the consumer.
672

Condition measuring and lifetime modelling of disconnectors, circuit breakers and other electrical power transmission equipment

Westerlund, Per January 2017 (has links)
The supply of electricity is important in modern society, so the outages of the electric grid should be few and short, especially for the transmission grid. A summary of the history of the Swedish electrical system is presented. The objective is to be able to plan the maintenance better by following the condition of the equipment. The risk matrix can be used to choose which component to be maintained. The risk matrix is improved by adding a dimension, the uncertainty of the probability. The risk can be reduced along any dimension: better measurements, preventive maintenance or more redundancy. The number of dimensions can be reduced to two by following iso-risk lines calculated for the beta distribution. This thesis lists twenty surveys about circuit breakers and disconnectors, with statistics about the failures and the lifetime. It also presents about forty condition-measuring methods for circuit breakers and disconnectors, mostly applicable to the electric contacts and the mechanical parts. A method for scheduling thermography based on analysis of variance of the current is tried. Its aim is to reduce the uncertainty of thermography and it is able to explain two thirds of the variation using the time of the day, the day of the week and the week number as explanatory variables. However, the main problem remains as the current is in general too low. A system with IR sensors has been installed at the nine contacts of six disconnectors with the purpose of avoiding outages for maintenance if the contacts are in a good condition. The measured temperatures are sent by radio and regressed against the square of the current, the best exponent found. The coefficient of determination $R^2$ is high, greater than 0.9. The higher the regression coefficient is, the more heat is produced at the contact. So this ranks the different contacts. Finally a framework for lifetime modelling and condition measuring is presented. Lifetime modelling consists in associating a distribution of time to failure with each subpopulation. Condition measuring means measuring a parameter and estimating its value in the future. If it exceeds a threshold, maintenance should be carried out. The effect of maintenance of the contacts is shown for four disconnectors. An extension of the risk matrix with uncertainty, a survey of statistics and condition monitoring methods, a system with IR sensors at contacts, a thermography scheduling method and a framework for lifetime modelling and condition measuring are presented. They can improve the planning of outages for maintenance. Finally a framework for lifetime modelling and condition measuring is presented. Lifetime modelling consists in associating a distribution of time to failure with each subpopulation. Condition measuring means measuring a parameter and estimating its value in the future. If it exceeds a threshold, maintenance should be carried out. The effect of maintenance of the contacts is shown for four disconnectors. An extension of the risk matrix with uncertainty, a survey of statistics and condition monitoring methods, a system with IR sensors at contacts, a thermography scheduling method and a framework for lifetime modelling and condition measuring are presented. They can improve the planning of outages for maintenance. / Elförsörjningen är viktig i det moderna samhället, så avbrotten bör vara få och korta, särskilt i stamnätet. En kortfattad historik över det svenska elsystemet presenteras. Målet är att kunna planera avbrotten för underhåll bättre genom att veta mera om apparaternas skick. Det är svårt att planera avbrott för underhåll och utbyggnad. Riskmatrisen är verktyg för att välja vad som ska underhållas och den kan förbättras genom att lägga till en dimension, sannolikhetens osäkerhet. Risken kan minskas längs med varje dimension: bättre mätningar, förebyggande underhåll och mer redundans. Antalet dimensioner kan igen bli två genom att följa linjer med samma risk, som är beräknade för betafördelningen. Denna avhandling tar upp tjugo studier av fel i brytare och frånskiljare med data om felorsak och livslängd. Den har också en översikt av ett fyrtiotal olika metoder för tillståndsmätningar för brytare och frånskiljare, som huvudsakligen rör de elektriska kontakterna och de mekaniska delarna. Ett system med IR sensorer har installerats på de nio kontakterna på sex frånskiljare. Målet är att minska antalet avbrott för underhåll genom att skatta skicket när frånskiljarna är i drift. De uppmätta temperaturerna tas emot genom radio och behandlas genom regression mot kvadraten av strömmen, då den bästa exponenten för strömmen visade sig vara 2,0. Förklaringsfaktorn $R^2$ är hög, över 0,9. För varje kontakt ger det en regressionskoefficient. Ju högre koefficienten är, desto mer värme utvecklas det i kontakten, vilket kan leda till skador på materialet. Koefficienterna ger en rangordning av frånskiljarna. Systemet kan också användas för att minska eller öka den tillåtna strömmen baserat på skicket. Slutligen förklaras ett ramverk för livslängdsmodellering och tillståndsmätning. Livslängdsmodellering innebär att koppla en fördelning för tiden till fel med varje delpopulation. Med tillståndsmätning avses att mäta en parameter och skatta dess värde i framtiden. Om den överskrider en tröskel, måste apparaten underhållas. Effekten av underhåll visas för fyra frånskiljare. En utveckling av riskmatrisen med osäkerheten, en sammanställning av statistik och metoder för tillståndsövervakning, ett system med IR-sensor vid kontakerna, en metod för termografiplanering och ett ramverk för livslängdsmodellering och tillståndsmätningar presenteras. De kan förbättra avbrottsplaneringen. / El suministro de energía eléctrica es importante en la sociedad moderna. Por eso los cortes eléctricos deben ser poco frecuentes y de poca duración, sobre todo en la red de transmisión. Esta tesis resume la historia del sistema eléctrico sueco. El objetivo es planificar los cortes mejor siguiendo la condición de los aparatos. La matriz de riesgo se utiliza muchas veces para escoger en qué aparatos debería realizarse mantenimiento. Esta matriz se puede mejorar añadiendo una dimensión: la incertidumbre de la probabilidad. El riesgo puede ser disminuido siguiendo cada una de las tres dimensiones: mejores mediciones, mantenimiento preventivo y mayor redundancia. El número de dimensiones puede reducirse siguiendo líneas del mismo riesgo calculadas para la distribución beta. Esta tesis presenta veinte estudios de fallos en interruptores y seccionadores con datos sobre la causa y el tiempo hasta la avería. Contiene también una visión general de cuarenta métodos para medir la condición de seccionadores e interruptores, aplicables en su mayoría a los contactos eléctricos y los componentes mecánicos. Se ha instalado un sistema con sensores infrarrojos en los seis contactos de nueve seccionadores. El objetivo es disminuir los cortes de servicio para mantenimiento, estimando la condición con el seccionador en servicio. Las temperaturas son transmitidas por radio y se hace una regresión con el cuadrado de la corriente, ya que el mejor exponente de la corriente resultó ser 2,0. $R^2$ alcanza un valor de 0,9 indicando un buen ajuste de los datos por parte del modelo. Existe un coeficiente de regresión para cada contacto y este sirve para ordenar los contactos según la necesidad de mantenimiento, ya que cuanto mayor sea el coeficiente más calor se produce en el contacto. Finalmente se explica que el modelado de tiempo hasta la avería consiste en asignar una distribución estadística a cada equipo. La monitorización del estado consiste en medir y estimar un parámetro y luego predecir su valor en el futuro. Si va a sobrepasar un cierto límite, el equipo necesitará de mantenimiento. Se presenta el efecto de mantenimiento de cuatro seccionadores. Un desarrollo de la matriz de riesgo, un conjunto de estadísticas y métodos de monitoreo de condición, un sistema de sensores IR situados cerca de los contactos, en método de planificación de termografía y un concepto para explicar la modelización de tiempo hasta la avería y de la monitorización de la condición han sido presentados y hace posible una mejor planificación de los cortes de servicio. / <p>QC 20170928</p>
673

[en] FALL RISK ANALYSIS DURING VR INTERACTION / [pt] ANÁLISE DO RISCO DE QUEDA DURANTE A INTERAÇÃO COM AMBIENTES DE REALIDADE VIRTUAL

ARMANDO ENRIQUE MARTINEZ GONZALEZ 28 July 2017 (has links)
[pt] Com o aumento da popularidade e acessibilidade de sistemas de realidade virtual (RV) de alta qualidade, tem-se levantado preocupações com relação a tendência dos sistemas de realidade virtual em provocar perda de equilíbrio. O equilíbrio é essencial para o uso seguro da realidade virtual e a perda do mesmo pode causar lesões graves. O objetivo deste trabalho é criar um sistema para avaliar o impacto da realidade virtual no equilíbrio humano. Neste trabalho, propomos e conduzimos um experimento usando o Oculus Rift e o MS Kinect Sensor. Nesse experimento, foi possível observar, quantificar e comparar o efeito de diferentes cenas de RV no equilíbrio dos usuários, bem como o efeito de avisos visuais e sonoros sobre perda de equilíbrio. / [en] With the increasing popularity and accessibility of high-quality Virtual Reality (VR) systems, concerns have been raised about the propensity of VR to induce balance loss. Balance is essential for safe use of VR experience and its loss can result in severe injury. This project is set to create a system able to measure the impact of VR in the human balance system. In this work, we design and conduct an experiment making use of the Oculus Rift VR headset and MS Kinect Sensor. In this experiment, we are able to visualize, quantify, and compare the effect of different VR scenes on the balance of the experiment subjects as well as the effect of visual and auditory warnings of balance loss.
674

Modélisation, prévision et couverture du risque de contagion financière / Modeling, forecasting and hedging financial contagion

Fofana, Lazeni 15 December 2015 (has links)
Cette thèse porte sur la modélisation, la prévision et la couverture du risque de contagion financière. Après une présentation générale des fondements théoriques et des mécanismes de propagation relatifs à la contagion financière, nous introduisons une modélisation fondée sur les modèles de cointégration non linéaire et de causalité non linéaire dans lesquels, les variables et le terme d’erreur du modèle à correction d’erreur obéissent à la dynamique de processus auto-régressifs à changement de régime de type TAR et M-TAR pour capter l’effet de contagion. Une extension de cette modélisation au cadre de prévision probabiliste conditionnelle a été faite par la suite à travers les réseaux de croyance Bayésienne pour renforcer le pouvoir prédictif. Ensuite, nous montrons comment une institution financière peut couvrir son portefeuille contre ce type de risque par de nouvelles approches. Nous proposons pour cela, une stratégie de couverture purement statique dans une perspective règlementaire à l’aide de modèles génératifs de type Vines-copula, une stratégie de couverture semi-statique fondée sur la budgétisation des risques et une stratégie de couverture dynamique à partir des processus de diffusion à sauts mutualisés. Ces nouvelles modélisations sont testées empiriquement sur un ensemble d’indices boursiers. / This Ph.D thesis focuses on modeling, forecasting and hedging financial contagion. After an overview of the theoretical foundations and spread mechanism relating to financial contagion, we introduce modeling based on nonlinear cointegration and non-linear causality models in which the variables and the error term in the correction model error obey at the dynamics of autoregressive regime change process of type TAR and M-TAR to catch the contagion effect. An extension of this model to conditional probabilistic forecasting framework was done through Bayesian belief networks, to enhance the predictive power. Then we show how a financial institution can hedge its portfolio against this risk by new specifications. Therefore, we offer a purely static hedging strategy in a regulatory perspective using generative models Vines-copula, a semi-static hedging strategy based on risk budgeting and dynamic hedging strategy based on mutually exciting jumps diffusion process. These new models are tested empirically on set of market indices.
675

Zavádění bezpečnostní politiky ve firmě / Security policy implementation in a selected company

Doležalová, Eliška January 2017 (has links)
This diploma thesis examines the process of preparation and implementation of a security policy as a means of information asset security management. The theoretical part describes security policies as an important part of information security management systems in a company and discusses the issue of virtual teams in terms of safety risks they pose for information security. This theoretical knowledge is applied in the practical part of the thesis where a security policy is composed for a small IT company with virtual team organization.
676

A Multi-Criteria GIS-Based Route Selection Tool for Hazardous Material Transport: Consideration of Environmental Consequence, Traffic Congestions and Costs

Inanloo, Bahareh 23 October 2015 (has links)
Hazardous materials are substances that, if not regulated, can pose a threat to human populations and their environmental health, safety or property when transported in commerce. About 1.5 million tons of hazardous material shipments are transported by truck in the US annually, with a steady increase of approximately 5% per year. The objective of this study was to develop a routing tool for hazardous material transport in order to facilitate reduced environmental impacts and less transportation difficulties, yet would also find paths that were still compelling for the shipping carriers as a matter of trucking cost. The study started with identification of inhalation hazard impact zones and explosion protective areas around the location of hypothetical hazardous material releases, considering different parameters (i.e., chemicals characteristics, release quantities, atmospheric condition, etc.). Results showed that depending on the quantity of release, chemical, and atmospheric stability (a function of wind speed, meteorology, sky cover, time and location of accidents, etc.) the consequence of these incidents can differ. The study was extended by selection of other evaluation criteria for further investigation because health risk as an evaluation criterion would not be the only concern in selection of routes. Transportation difficulties (i.e., road blockage and congestion) were incorporated as important factor due to their indirect impact/cost on the users of transportation networks. Trucking costs were also considered as one of the primary criteria in selection of hazardous material paths; otherwise the suggested routes would have not been convincing for the shipping companies. The last but not least criterion was proximity of public places to the routes. The approach evolved from a simple framework to a complicated and efficient GIS-based tool able to investigate transportation networks of any given study area, and capable of generating best routing options for cargos. The suggested tool uses a multi-criteria-decision-making method, which considers the priorities of the decision makers in choosing the cargo routes. Comparison of the routing options based on each criterion and also the overall suitableness of the path in regards to all the criteria (using a multi-criteria-decision-making method) showed that using similar tools as the one proposed by this study can provide decision makers insights in the area of hazardous material transport. This tool shows the probable consequences of considering each path in a very easily understandable way; in the formats of maps and tables, which makes the tradeoffs of costs and risks considerably simpler, as in some cases slightly compromising on trucking cost may drastically decrease the probable health risk and/or traffic difficulties. This will not only be rewarding to the community by making cities safer places to live, but also can be beneficial to shipping companies by allowing them to advertise as environmental friendly conveyors.
677

Bezpečnost firemních telefonních sítí využívajících VoIP / Security of Enterprise VoIP Telephony Networks

Šolc, Jiří January 2008 (has links)
This thesis focuses on enterprise VoIP telephony network security. Introduces brief comparison of old analog and digital voice networks and IP telephone networks with special focus on VoIP system security. The goal of the thesis is to identify the risks of implementation and operation of VoIP technologies in enterprise environment and so thesis brings some conclusion how to minimalize or avoid these risks. First two chapters briefly introduce the development of telephony technologies with differentiation of enterprise telephone network from public telephone networks. Further it describes individual technologies, digitalization of voice, processing the signal and VoIP protocols and components. Third chapter focuses on infrastructure of telephony networks with special interest for architecture of IP telephony and ways of establishing call processing. It describes data flows for further security risk analysis, which this technology came with. Fifth chapter is about enterprise security standards in common and is trying to describe information security management system (ISMS) adopting VoIP technology. Individual security threats and risks are described in sixth chapter, along with known methods how to avoid them. Final parts of thesis concludes of two real situation studies of threats and risks of VoIP technologies implemented in environment of small commercial enterprise and medium size enterprise, in this example represented by University of economics. These chapters conclude theoretical problems shown on practical examples.
678

Bezpečnost a ochrana dat a informací v bankovnictví pro manažery / Security and Protection of Data and Information in Banking Business for Managers

Melichar, Jan January 2009 (has links)
This dissertation describes information as an economic object and focuses on information security with reference to all technical and social aspects and documents the necessity to consider both those areas simultaneously. The dissertation determines information security standards and describes some tools being used for effective data protection and information systems protection. One part of this dissertation is a model design for effective controlling of data and process protection, which can be used by bank managers on process control design especially in transaction processing area. This model is divided into several logical and consequential blocks and provides help to operating managers to design or redesign new or existing processes accordingly. The dissertation clearly highlights related insufficiencies especially those related to data access protection and passwords and one related survey has been performed to prove that
679

Informačná bezpečnosť a riadenie rizík v konkrétnej spoločnosti / Information security and risk management in a particular company.

Slávková, Daniela January 2012 (has links)
The aim of the thesis is to apply the methodology of qualitative risk analysis according to ISO/EC/27005:2011 and to increase awareness of existing threats and impacts on information assets and to create possible security precautions to minimize identified threats in a particular company. The thesis is divided into five chapters. Introductory chapter explains the basic concepts of information security and risk management in the organization that are necessary for understanding of the principles and the importance of information security. The second chapter deals with the international standards aimed at information security and briefly describes ISO/IEC 27001, ISO/IEC 27002 and ISO/IEC 27005. The following two chapters form a smooth transition from the theoretical to the practical part. The third chapter characterizes selected company and describes the current state of information security in the company. The fourth chapter forms the methodological apparatus of qualitative risk analysis, compiled in accordance with ISO/IEC 27005:2011. It also contains a list of relevant threats, to which an asset of the company is exposed. The last chapter is conducted to qualitative risk analysis, together with the draft of the precautions to minimize the risks. The practical section shows that by the implementing the proposed action the company will reduce existing risks to acceptable levels and will significantly improve the protection of information assets.
680

Podnikatelský plán / Business plan

Bláhová, Karolína January 2016 (has links)
This thesis focuses on developing a business plan for the production of baby food. The thesis consists of three parts. The main purpose of the theoretical part is to introduce the reader the environment of small and medium enterprise subsequently to describe the proper writing of a business plan. There are also recommendations for suitable structures procedures. Methodical part deals with the proper execution of marketing research, considerable attention particularly a method of interrogation. The practical part is the business plan itself. The aim of this thesis is to evaluate the feasibility of the project and its ability to prosper at today's market.

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