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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.
21

Hacia una adecuada infraestructura nacional de la calidad en Chile

Aravena Muñoz, Dayana 05 1900 (has links)
TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN POLÍTICAS PÚBLICAS / La integración comercial ha avanzado a pasos agigantados, las barreras y dificultades comerciales son mínimas y los costos de traslado han disminuido. Las mejoras en la infraestructura física y económica, los desarrollos tecnológicos y en sistemas de información, mejores procesos de fabricación, transporte y otras mejoras que impactan directamente a las industrias y al comercio de productos y servicios, han generado un aumento acelerado del número de transacciones comerciales intra e inter mercados. Se han firmado tratados y convenios de comercio internacional y con ellos se han establecido reglas que enmarcan las relaciones comerciales como el Acuerdo sobre Obstáculos Técnicos al Comercio y el Acuerdo sobre la Aplicación de Medidas Sanitarias y Fitosanitarias, que cada miembro de la Organización Mundial de Comercio debe adscribir. Durante el 2016, se firmó el Acuerdo de Asociación Transpacífico (TTP) entre 12 países de América Latina y el Caribe (entre ellos Chile), América del Norte, Asia y Oceanía. EL TTP representa la mayor área de comercio medida como el PIB conjunto de sus integrantes y se caracteriza por tener una fuerte intención de armonización reglamentaria en áreas como el comercio electrónico, propiedad intelectual y cuidados medioambientales. Actualmente existe mucha incertidumbre respecto de su entrada en vigor por posibles efectos negativos sobre pequeños productores y también por conflictos políticos entre algunos miembros, no obstante, es un ejemplo de lo que significa la ganancia por mejora en las negociaciones y exportaciones de Chile (por ejemplo, agrícolas y agroindustriales) ante la presencia de acuerdos comerciales. Los potenciales beneficios de este y otros tratados, requieren de fuertes políticas industriales, tecnológicas y de innovación para dar respuesta a las exigencias internacionales. ¿Chile está preparado?. Los acuerdos comerciales se basan en la confianza y reconocimiento entre sus miembros. ¿Qué pasa si incumplimos los requisitos armonizados en la reglamentación? Podemos evaluar la respuesta mirando el caso de la exportación de salmón de Chile que excedió la cantidad de antibióticos permitida según los requisitos de ingreso de nuestro socio comercial Estados Unidos. El resultado fue la sustitución del mercado chileno por el mercado noruego y grandes pérdidas monetarias que se suman a la perdida de confianza en el aseguramiento de la calidad que brinda el país. Ejemplos como este, existen muchos en todas las regiones y en particular afectan principalmente a los países en desarrollo por su fuerte dependencia de la exportación de productos y servicios y las limitadas capacidades de establecer un sólido marco regulatorio e institucional que permita una mayor competitividad en el mercado internacional. Según la Organización para Cooperación y el Desarrollo Económico (OCDE, 1999), el 80% del comercio mundial total se ve afectado por normas y requisitos técnicos; y entre un 2% y 10% del costo total de producción se destinan a cumplir con las mismas (OCDE, 1996). Es decir que, si los países en vías de desarrollo buscan ingresar al mercado globalizado, deben poder contar con recursos relacionados al acceso a normas, capacidades de mediciones exactas, servicios de certificación y ensayos y acreditación. Todo esto es parte de lo que se llama Infraestructura de la Calidad. El crecimiento industrial sostenido ha sido motivo de creación de organizaciones que apoyen a los países en desarrollo o en transición para el fortalecimiento de las capacidades comerciales. En este contexto la Organización de las Naciones Unidas para el Desarrollo Industrial ha planificado y creado infraestructuras de la calidad donde no existían para maximizar las capacidades comerciales a nivel regional e internacional, movilizando conocimiento, destrezas, información y tecnología para apoyar el comercio y el desarrollo industrial. Se ha consensuado que la infraestructura de la calidad constituye un catalizador para la mejora de la calidad de los productos y servicios que se transan en los mercados y que, en consecuencia, ayuda a estimular la demanda de estos, lo que vigoriza negocios y la economía en general. Al contribuir con la industria nacional a satisfacer los requerimientos de los mercados de exportación, la infraestructura de la calidad aumenta la competitividad de la economía del país y su capacidad para participar en el comercio mundial y cadenas de valor, resguardando la seguridad del ciudadano y el medio ambiente. En síntesis, la infraestructura de la calidad entrega confianza al cliente y/o usuario cuando adquiere determinado bien o servicio. En adición, los servicios prestados por la infraestructura de la calidad, son grandes propulsores de nuevos avances sociales y tecnológicos, todos sus elementos ayudan a la sociedad y a la economía a hacer frente a distintos desafíos en un entorno cambiante, mediante la creación y difusión de nuevas tecnologías. Por ejemplo, para poder tener una comunicación eficiente se requiere de normas terminológicas para transferencia de conocimiento (normalización); o como el caso del sistema mundial de determinación de la posición (GPS) que se relaciona íntimamente con los avances en las esferas de la metrología científica; o bien cómo se han incorporado los sellos de rotulado energético a los electrodomésticos para orientar a la demanda a consumo eficiente de energía (acreditación y evaluación de la conformidad). En conexión con la relevancia de la IC en la estructura económica y la competitividad comercial, la incorporación de este tema en la agenda de discusión de política pública significa un gran avance en términos de la institucionalidad y marco regulatorio coherente y eficiente en sus iniciativas e interacciones. Este estudio constituye un esfuerzo de levantamiento de ideas, ciertas acciones y decisiones de política para el desafío de desarrollo de la Infraestructura Nacional de la Calidad chilena. Cabe mencionar que no se incorpora análisis econométrico, dada la escasa existencia de datos y a que el foco se mantuvo en generar un marco conceptual común para comenzar a generar conocimiento y literatura nacional sobre el tema. A su vez, esto se enlaza con un estudio previo de Evaluación del Impacto de la Infraestructura de la Calidad chilena en la Productividad1 solicitado por interés del Banco Interamericano de Desarrollo que levantó una serie de falencias respecto de lo que es en Chile una Infraestructura de la Calidad. El documento se divide en dos partes, en la primera se muestran las principales características de un modelo según las buenas prácticas internacionales y cómo se ha desarrollado en Chile. En ambos casos se abordan sus componentes, actores, institucionalidad, cifras de desempeño y otros, para cerrar posteriormente con una síntesis de impactos, beneficios y costos de la Infraestructura de la calidad en distintos ámbitos económicos y sociales. Luego, una segunda parte, enfrenta la discusión sobre las recomendaciones que acercarán a Chile hacia un correcto aseguramiento de la calidad, para lo cual en principio se compara el modelo según buenas prácticas con el existente a nivel nacional y luego se abordan los principales ámbitos de acción y decisión de política publica mediante recomendaciones.
22

Genetic Determinants of Plasma alpha-tocopherol

Garofalo, Francesca 27 June 2013 (has links)
alpha-tocopherol is the most abundant form of vitamin E in human plasma and tissues. Inter-individual differences in plasma alpha-tocopherol concentration or its response to dietary alpha-tocopherol may be due, in part, to polymorphisms in vitamin E metabolism genes (alpha-tocopherol transfer protein (alpha-TTP), tocopherol associated protein (TAP) and CYP4F2). The thesis objectives were to determine whether common polymorphisms in the alpha-TTP (rs6994076 A>T), TAP (rs2072157 C>T and Arg11Lys) and CYP4F2 (Val433Met) genes influence plasma alpha-tocopherol concentration or modify the association between dietary and plasma alpha-tocopherol. Subjects (n=1248), 20 to 29 years from the Toronto Nutrigenomics and Health study completed a food frequency questionnaire. Fasting blood samples were used for genotyping and to measure plasma alpha-tocopherol concentration. The alpha-TTP and TAP Arg11Lys polymorphisms significantly altered plasma alpha-tocopherol. The alpha-TTP polymorphism only influenced plasma alpha-tocopherol in individuals not using supplements. None of the polymorphisms examined modified the plasma alpha-tocopherol response to dietary alpha-tocopherol.
23

Genetic Determinants of Plasma alpha-tocopherol

Garofalo, Francesca 27 June 2013 (has links)
alpha-tocopherol is the most abundant form of vitamin E in human plasma and tissues. Inter-individual differences in plasma alpha-tocopherol concentration or its response to dietary alpha-tocopherol may be due, in part, to polymorphisms in vitamin E metabolism genes (alpha-tocopherol transfer protein (alpha-TTP), tocopherol associated protein (TAP) and CYP4F2). The thesis objectives were to determine whether common polymorphisms in the alpha-TTP (rs6994076 A>T), TAP (rs2072157 C>T and Arg11Lys) and CYP4F2 (Val433Met) genes influence plasma alpha-tocopherol concentration or modify the association between dietary and plasma alpha-tocopherol. Subjects (n=1248), 20 to 29 years from the Toronto Nutrigenomics and Health study completed a food frequency questionnaire. Fasting blood samples were used for genotyping and to measure plasma alpha-tocopherol concentration. The alpha-TTP and TAP Arg11Lys polymorphisms significantly altered plasma alpha-tocopherol. The alpha-TTP polymorphism only influenced plasma alpha-tocopherol in individuals not using supplements. None of the polymorphisms examined modified the plasma alpha-tocopherol response to dietary alpha-tocopherol.
24

Hospodaření na trvalých travních porostech a struktura živočišné výroby v podnicích s jejich převahou / Farming on permanent grassland and structure of animal husbandry in enterprises with their superiority

SEDLECKÝ, Pavel January 2010 (has links)
The Thesis was elaborated on the theme: Farming on permanent grassland (PG) and structure of animal husbandry in enterprises with their superiority. The aim was to analyze number of cattle, milk and meat production, the proportion of PG in Czech Republic and detail in the South Bohemia. A working hypothesis was set as follows, that with increasing altitude, increasing the proportion of grassland. From 1989 till 2009 in the Czech Republic the acreage of grassland increased about 100 thousand he, but in the same period decreased by 2 100 000 pieces in cattle. This has resulted in insufficient load {--} 0.7 LU/he. For comparison I show the average load in the EU {--} 1.1 LU/he. The results show that the proportion of PG in the Czech Republic had increased, but grassing should be more focused. It should also improve the structure of livestock farming on PG and thereby achieve an increase in load and LU/he.
25

Optimalizace predikce pozice v síti / Optimization of network position prediction

Pospíšil, Petr January 2008 (has links)
This work is about position prediction in network, it is focused to find Landmark closest to the Host in the network (with lowest distance vector). The algorithm is based on GNP system. In terms of GNP system simulation was selected method for mathematical part of position prediction. The method was Simplex Downhill. The designed algorithm was implemented in Java. In the first step chose Host continent by meassuring the distance vector. In next step is selected nearest part in the continent. In conclusion estimate Host its position and then closest Landmark. Results from this work is important for designing TTP protocol. The verdict is that the GNP can be used for TTP, but Landmarks must be located in uniform density.
26

Support consumers' rights in DRM : a secure and fair solution to digital license reselling over the Internet

Gaber, Tarek January 2012 (has links)
Consumers of digital contents are empowered with numerous technologies allowing them to produce perfect copies of these contents and distribute them around the world with little or no cost. To prevent illegal copying and distribution, a technology called Digital Rights Management (DRM) is developed. With this technology, consumers are allowed to access digital contents only if they have purchased the corresponding licenses from license issuers. The problem, however, is that those consumers are not allowed to resell their own licenses- a restriction that goes against the first-sale doctrine. Enabling a consumer to buy a digital license directly from another consumer and allowing the two consumers to fairly exchange the license for a payment are still an open issue in DRM research area. This thesis investigates existing security solutions for achieving digital license reselling and analyses their strengths and weaknesses. The thesis then proposes a novel Reselling Deal Signing (RDS) protocol to achieve fairness in a license reselling. The idea of the protocol is to integrate the features of the concurrent signature scheme with functionalities of a License Issuer (LI). The security properties of this protocol is informally analysed and then formally verified using ATL logic and the model checker MOCHA. To assess its performance, a prototype of the RDS protocol has been developed and a comparison with related protocols has been conducted. The thesis also introduces two novel digital tokens a Reselling Permission (RP) token and a Multiple Reselling Permission (MRP) token. The RP and MRP tokens are used to show whether a given license is single and multiple resalable, respectively. Moreover, the thesis proposes two novel methods supporting fair and secure digital license reselling. The first method is the Reselling Deal (RD) method which allows a license to be resold once. This method makes use of the existing distribution infrastructure, RP, License Revocation List (LRL), and three protocols: RDS protocol RD Activation (RDA) protocol, and RD Completion (RDC) protocol. The second method is a Multiple License Reselling (MLR) method enabling one license to be resold N times by N consumers. The thesis presents two variants of the MLR method: RRP-MR (Repeated RP-based Multi-Reselling) and HC-MR (Hash Chain-based Multi-Reselling). The RRP-MR method is designed such that a buyer can choose to either continue or stop a multi-reselling of a license. Like the RD method, the RRP-MR method makes use of RP, LI, LRL, and the RDS, RDA, and RDC protocols to achieve fair and secure reselling. The HC-MR method allows multiple resellings while keeping the overhead on LI at a minimum level and enable a buyer to check how many times a license can be further resold. To do so, the HC-MR utilises MRP and the hash chain cryptographic primitive along with LRL, LI and the RDS, RDA and RDC protocols. The analysis and the evaluation of these three methods have been conducted. While supporting the license reselling, the two methods are designed to prevent a reseller from (1) continuing using a resold license, (2) reselling a non-resalable license, and (3) reselling one license a unauthorised number of times. In addition, they enable content owners of resold contents to trace a buyer who has violated any of the usage rights of a license bought from a reseller. Moreover, the methods enable a buyer to verify whether a license he is about to buy is legitimate for re-sale. Furthermore, the two methods support market power where a reseller can maximise his profit and a buyer can minimise his cost in a reselling process. In comparison with related works, our solution does not make use of any trusted hardware device, thus it is more cost-effective, while satisfying the interests of both resellers and buyers, and protecting the content owner's rights.
27

Régulations épigénétiques et rôles de la protéine Btk dans l'expression du TNF-α par la voie des TLRs

Frenzel, Laurent 02 September 2013 (has links) (PDF)
La Bruton tyrosine kinase ou Btk est une protéine dont le rôle dans la maturation des lymphocytes B est connu depuis plusieurs années. Par contre, son rôle dans le contrôle de l'immunité innée est moins établi. Nous avons montré que, en réponse à la voie des Toll like Receptors ou TLRs, Btk régule la stabilité de l'ARN messager du TNF-α par l'intermédiairede la protéine TTP ou Tristétraproline. Par ailleurs, nous avons montré que l'expression d'un microARN, le miR-346, régulait négativement la protéine Btk et donc la synthèse de TNF-α. L'amplification de l'expression de ce miR-346 par transfection permet d'avoir un effet anti-TNF-α et anti-Btk interessant notamment dans le modèle cellulaire de la polyarthrite rhumatoïde. Enfin, nous avons montré que, en réponse au TLRs, la modulation de l'expression du TNF-α en fonction de l'état de méthylation de l'ADN et d'acétylation des histones dépendait directement de l'expression du couple miR-346 et Btk. Btk est donc une protéine charnière dans le contrôle de l'inflammation par les mécanismes épigénétiques que sont les miARNs, la méthylation de l'ADN et l'acétylation des histones. Sur le plan thérapeutique, l'inhibition de cette protéine par ces différents mécanismes de régulation semble donc être très interessante, à la fois dans les maladies inflammatoires et néoplasiques.
28

Biodiverzita epigeických brouků na vybraných polních kulturách - vliv managementu na strukturu společenstev / Biodiversity of epigeic beetles on selected field crops - effects of management on the structure of communities

SVOBODA, Richard January 2012 (has links)
Epigeických beetle communities were studied on four agroecosystems with different crops grown. All four agroecosystems were located in the vicinity of Czech Budejovice (South Bohemia). The first agroecosystem is conventionally grown corn. On the second one agroecosystem it was conventionally grown wheat. The third agroecosystem was barley and the fourth was permanent grassland. Individual agroekosystems differed not only in crops but also in agrotechnical operations during the capture. In all agroecosystems was for capture of the material used method of pitfall traps. Subsequently, those types have been studied. Then was studied degree of human impact on the biodiversity of species of different ecological groups found in these locations.Beetle activity was highest in the maize agroecosystem. There was found almost half of all captured individuals. In all agroecosystems was activity affected by management of agrotechnic operations and also by for that year specific weather. All sites were completely dominated by expansive species (E - types of deforested habitats strongly influenced by human activities)
29

Securing data dissemination in vehicular ad hoc networks

Aldabbas, Hamza January 2012 (has links)
Vehicular ad hoc networks (VANETs) are a subclass of mobile ad hoc networks (MANETs) in which the mobile nodes are vehicles; these vehicles are autonomous systems connected by wireless communication on a peer-to-peer basis. They are self-organized, self-configured and self-controlled infrastructure-less networks. This kind of network has the advantage of being able to be set-up and deployed anywhere and anytime because it has no infrastructure set-up and no central administration. Distributing information between these vehicles over long ranges in such networks, however, is a very challenging task, since sharing information always has a risk attached to it especially when the information is confidential. The disclosure of such information to anyone else other than the intended parties could be extremely damaging, particularly in military applications where controlling the dissemination of messages is essential. This thesis therefore provides a review of the issue of security in VANET and MANET; it also surveys existing solutions for dissemination control. It highlights a particular area not adequately addressed until now: controlling information flow in VANETs. This thesis contributes a policy-based framework to control the dissemination of messages communicated between nodes in order to ensure that message remains confidential not only during transmission, but also after it has been communicated to another peer, and to keep the message contents private to an originator-defined subset of nodes in the VANET. This thesis presents a novel framework to control data dissemination in vehicle ad hoc networks in which policies are attached to messages as they are sent between peers. This is done by automatically attaching policies along with messages to specify how the information can be used by the receiver, so as to prevent disclosure of the messages other than consistent with the requirements of the originator. These requirements are represented as a set of policy rules that explicitly instructs recipients how the information contained in messages can be disseminated to other nodes in order to avoid unintended disclosure. This thesis describes the data dissemination policy language used in this work; and further describes the policy rules in order to be a suitable and understandable language for the framework to ensure the confidentiality requirement of the originator. This thesis also contributes a policy conflict resolution that allows the originator to be asked for up-to-date policies and preferences. The framework was evaluated using the Network Simulator (NS-2) to provide and check whether the privacy and confidentiality of the originators’ messages were met. A policy-based agent protocol and a new packet structure were implemented in this work to manage and enforce the policies attached to packets at every node in the VANET. Some case studies are presented in this thesis to show how data dissemination can be controlled based on the policy of the originator. The results of these case studies show the feasibility of our research to control the data dissemination between nodes in VANETs. NS-2 is also used to test the performance of the proposed policy-based agent protocol and demonstrate its effectiveness using various network performance metrics (average delay and overhead).

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