Made available in DSpace on 2015-04-14T14:52:20Z (GMT). No. of bitstreams: 1 434793.pdf: 1295703 bytes, checksum: 568e7db4f4ec20fdf7d1442466026768 (MD5) Previous issue date: 2011-08-31 / O aumento da competitividade em ?mbito global e a redu??o das barreiras ao com?rcio internacional t?m for?ado as empresas a atuarem em um ambiente cada vez mais complexo, deparando-se com situa??es, muitas vezes, ainda n?o estudadas em profundidade no meio acad?mico. Para enfrentar a alta competitividade, as empresas est?o se unindo em arranjos organizacionais com o objetivo de obter resultados melhores ao atuarem sob forma de uma cadeia de suprimentos. Tais cadeias de suprimentos por vezes agregam empresas presentes em v?rios pa?ses, fato que tem sido maximizado pela redu??o das barreiras comerciais, atrav?s da internacionaliza??o de compras, que representa o aumento da disponibilidade e da oferta de materiais, permitindo que a busca por insumos produtivos v? al?m das fontes do mercado dom?stico.Neste contexto, este trabalho trata da an?lise da internacionaliza??o de compras em empresas brasileiras participantes de uma cadeia de suprimentos de uma ind?stria multinacional instalada na regi?o sul do Brasil. Mais especificamente, o trabalho visa mostrar qual a rela??o entre o est?gio de internacionaliza??o de compras das empresas fornecedoras e os requisitos de desempenho impostos pela empresa foco da cadeia de suprimentos analisada. Al?m disso, visa tamb?m identificar os fatores motivadores e inibidores, sob o ponto de vista dos fornecedores, da internacionaliza??o de compras e a influ?ncia dos crit?rios utilizados pela empresa focal para medir o desempenho destas empresas. Por ?ltimo, visa, ainda, identificar como as empresas fornecedoras desta cadeia de suprimentos analisam o seu processo de compras, em especial as compras internacionais.Este estudo foi realizado atrav?s de uma pesquisa qualitativa, com o uso de estrat?gia de estudo de casos m?ltiplos com abordagem explorat?ria. A partir da revis?o da literatura, foram obtidos os elementos necess?rios para desenvolver o estudo e elaborar os instrumentos de pesquisas que foram aplicados em duas etapas: a primeira em entrevista com a empresa focal, onde foram obtidos os elementos necess?rios para a sele??o das empresas fornecedoras a participarem deste estudo, al?m da identifica??o dos crit?rios utilizados pela empresa focal na avalia??o da performance das mesmas; na segunda etapa foram abordadas as empresas fornecedoras, onde se buscou elementos para o atendimento dos objetivos propostos. Ap?s a an?lise das respostas obtidas junto ?s empresas (focal e fornecedores) e do cruzamento destas informa??es com a teoria, foi poss?vel concluir que em determinado tipo de relacionamento inter-organizacional existe influ?ncia da forma como a empresa focal analisa seus fornecedores nas estrat?gias de compras destes fornecedores e, ao mesmo tempo, tamb?m existe rela??o desta an?lise na percep??o desses fornecedores sobre os fatores que os motivam ou n?o a realizar compras internacionais. Por ?ltimo, foi poss?vel tamb?m concluir que as avalia??es realizadas pelas empresas fornecedoras, de suas pr?prias atividades de compras, n?o representam uma ponto forte para as mesmas.

Submitted by Elba Lopes (elba.lopes@fecap.br) on 2017-11-18T16:08:32Z No. of bitstreams: 2 Marcio Roberto de Souza.pdf: 3290425 bytes, checksum: beebb33e7919dbb799efa3b2b936dfb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-11-18T16:08:32Z (GMT). No. of bitstreams: 2 Marcio Roberto de Souza.pdf: 3290425 bytes, checksum: beebb33e7919dbb799efa3b2b936dfb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-28 / Understanding and practicing Supply Chain Management ??? SCM - with excellence has become a prerequisite for the continuity of the organizations in the era of network competition. However, even after some decades of evolution under the aegis of the systemic approach, the methodology still needs to provide instruments capable of measuring the economic results of this broader system, since the existing models in the area - SCOR and GSCF - do not fulfill this function in its completeness and, therefore, does not allow to check if the supply chain is effective. The probable solution of the problem passes through the use of innovations developed in the scope of Managerial Accounting such as the Model of Economic Management in the SCM. To the accounting-management artifact is attributed the concepts of economic events and economic profit - the best indicator of effectiveness of the "enterprise system" and, it is believed, the "supply chain system" - whose application in the context of the supply chain depends on the ability of managers from companies with greater bargaining power to perceive systems, because if they do not see it, they do not understand it or manage it strategically, nor do they know adequate measures for this angle of analysis. This work aimed, therefore, to know the systemic view of the managers of purchases of Brazilian retailers, of the areas of telephony and/or electronics products, on the process of management of the economic events of the upstream supply chain, not properly for that moment to apply a system of measurement of the global economic results of the system, but to investigate if there is fertile field to develop it, because these managers, supported by the company with greater bargaining power in the chain, have in their hands the decision about the economic event "purchase" and can influence the strategic objectives of the chains that their company integrates and the adoption of instruments to manage them. To achieve the proposed goal, the Focus Group technique was used with six retail managers and content analysis to handle the data collected at this stage. Subsequently, their inferences were investigated through questionnaires sent to retail purchasing managers from all over the country. The data of 44 respondents were modeled with logistic regression and it was verified that the congruence of objectives and the creation of knowledge together are the constructs that most influence the systemic vision that the managers have on the process of management of the economic events of the chain of and there is propensity for the development of systems for measuring the overall economic profit of the system. / Compreender e praticar o gerenciamento da cadeia de suprimentos ??? ou SCM, acr??nimo de Supply Chain Management ??? com excel??ncia tornou-se pr??-requisito para a continuidade das organiza????es na era da competi????o em rede. No entanto, mesmo depois de algumas d??cadas de evolu????o sob a ??gide da abordagem sist??mica, ainda falta ?? metodologia prover instrumentos capazes de mensurar os resultados econ??micos desse sistema mais amplo, pois os modelos existentes na ??rea ??? SCOR e GSCF ??? n??o cumprem essa fun????o em sua plenitude e, por isso, alijam a capacidade de conferir se a cadeia de suprimentos ?? eficaz. Conjectura-se que a solu????o do problema passa pelo aproveitamento no SCM de inova????es desenvolvidas no ??mbito da Contabilidade Gerencial como ?? o Modelo de Gest??o Econ??mica. Ao artefato cont??bil-gerencial se atribui os conceitos de eventos econ??micos e lucro econ??mico ??? o melhor indicador de efic??cia do ???sistema empresa??? e, acredita-se, do ???sistema cadeia de suprimentos??? ??? cuja aplica????o no contexto da cadeia de suprimentos depende da habilidade dos gestores das empresas integrantes com maior poder de barganha em perceber sistemas, pois se n??o o enxergam, n??o o compreendem nem o gerenciam de modo estrat??gico, nem tampouco conhecem medidas adequadas para esse ??ngulo de an??lise. Este trabalho buscou, portanto, conhecer a vis??o sist??mica dos gestores de compras de varejistas brasileiros, das ??reas de telefonia e/ou eletr??nicos, sobre o processo de gest??o dos eventos econ??micos da rede ?? montante, n??o propriamente para j?? nesse momento aplicar um sistema de mensura????o dos resultados econ??micos globais do sistema, mas sim para investigar se h?? campo f??rtil para desenvolv??-lo, pois esses gestores, suportados pela companhia com maior poder de barganha da rede, t??m em suas m??os a decis??o sobre o evento econ??mico ???compra??? e podem influenciar os objetivos estrat??gicos das cadeias que sua empresa integra e a ado????o de instrumentos para gerenci??-las. Para atingir o objetivo proposto, utilizou-se a t??cnica de Focus Group com seis gestores do varejo e an??lise de conte??do para tratar os dados levantados nessa etapa. Posteriormente, se investigou suas infer??ncias por meio de question??rios enviados a gestores de compras do varejo de todo o pa??s. Os dados de 44 respondentes foram modelados com regress??o log??stica e constatou-se que a congru??ncia de objetivos e a cria????o de conhecimento em conjunto s??o os constructos que mais influenciam a vis??o sist??mica que os gestores t??m sobre o processo de gest??o dos eventos econ??micos da cadeia de suprimentos e que h?? espa??o para o desenvolvimento de sistemas de mensura????o do lucro econ??mico global do sistema.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-17T19:08:45Z No. of bitstreams: 1 2015 - Waldenir Jose das Chagas de Oliveira.pdf: 1418599 bytes, checksum: 36c462f2863aa65bfdf908a2bf0bf8c8 (MD5) / Made available in DSpace on 2017-08-17T19:08:45Z (GMT). No. of bitstreams: 1 2015 - Waldenir Jose das Chagas de Oliveira.pdf: 1418599 bytes, checksum: 36c462f2863aa65bfdf908a2bf0bf8c8 (MD5) Previous issue date: 2015-04-30 / The purpose of this study is to analyze the logistic and collaborative actions with three associative supermarket networks located in the State of Rio de Janeiro. This research assumes that the business logistic and collaborative actions (vertical and horizontal) have important roles to obtain competitive advantages in an area that is getting more and more unstable, where the only ones to survive are the companies that are able to aggregate value to the client by offering quicker and more efficient answers. The field research is characterized by a multiple case study of qualitative approach, that happens in three associative supermarket network constituted of small and medial business owners. For the database research were elaborated three semi structured and distinctive scripts that allowed the implementation of sixteen interviews. The subjects of the research were the associates or buyers, managers and presidents, members of the three networks. It was concluded that the three networks studied in this research were able to develop throughout their years in business, feelings of trust and reciprocity capable of strengthening the relational coherency between associates. Although, it is important to highlight that the said networks still have a long way to improve until they can really become the "Business Network", nomenclature for which they were designated in this paper. The results found in this research indicate that the three networks need to amplify the scope of their collaborative actions in a way to transcend the stage of joint negotiation and reach a level of cooperation that allows to also be working together. Furthermore, it is necessary that the capacity to provide better gains and offer complementary resources could be extrapolate to something beyond buying or marketing shares, pervading the development of instate a strategy with associates and suppliers, that can contemplate: the improvement of merchandise transportation, managing the stock, managing by categories, defining a mix of products suitable for sale, integrated usage of technology tools of logistic support, amongst others. / O presente estudo teve como objetivo analisar as pr?ticas log?sticas e as a??es colaborativas observadas na atua??o de tr?s redes associativistas de supermercados localizadas no Estado do Rio de Janeiro. As implica??es dessa pesquisa pressup?em que a log?stica empresarial e a??es as colaborativas (verticais e horizontais) t?m pap?is importantes para obten??o de vantagens competitivas, em mercados cada vez mais vol?teis, onde sobrevivem de fato, as empresas que conseguem agregar valor ao cliente oferecendo respostas mais r?pidas e eficientes. A pesquisa de campo caracteriza-se por um estudo de caso m?ltiplo, de abordagem qualitativa, que se d? em tr?s redes associativistas de supermercados formadas por pequenos e m?dios empres?rios. Para coleta de dados foram elaborados tr?s roteiros semiestruturados distintos, que permitiram a realiza??o de dezesseis entrevistas. Os sujeitos da pesquisa s?o os associados ou compradores, gestores e presidentes, integrantes das tr?s redes. Conclui-se que as redes estudadas nessa pesquisa conseguiram desenvolver ao longo dos seus anos de atua??o sentimentos de confian?a e reciprocidade capazes de tornar mais forte a coes?o relacional entre os associados. Entretanto, ? importante ressaltar que as referidas redes ainda t?m um longo caminho evolutivo a percorrer at? que possam realmente fazer jus ? nomenclatura de ?Centrais de Neg?cios?, pela qual foram designadas nesse trabalho. Os resultados encontrados nessa pesquisa indicam que as tr?s redes precisam amplificar o escopo de suas a??es colaborativas, de maneira a transcender a fase de negociar em conjunto e alcan?ar um est?gio de coopera??o que permita tamb?m operar em conjunto. Desta forma, ? necess?rio que a capacidade de proporcionar os ganhos em escala e oferecer recursos complementares seja extrapolada para ir al?m da compra e das a??es marketing, perpassando o desenvolvimento de estrat?gias integradas com associados e fornecedores que contemplem: a melhoria do transporte de mercadorias, gerenciamento de estoque, gerenciamento por categoria, defini??o de um mix de produtos adequado ? venda, uso integrado de ferramentas tecnologias de apoio log?stico, entre outras.

Past focus in the panel gravity literature has been on multidimensional fixed effects specifications in an effort to accommodate heterogeneity. After introducing conventional multidimensional fixed effects, we find evidence of cross-sectional dependence in flows. We propose a simultaneous dependence gravity model that allows for network dependence in flows, along with computationally efficient Markov Chain Monte Carlo estimation methods that produce a Monte Carlo integration estimate of log-marginal likelihood useful for model comparison. Application of the model to a panel of trade flows points to network spillover effects, suggesting the presence of network dependence and biased estimates from conventional trade flow specifications. The most important sources of network dependence were found to be membership in trade organizations, historical colonial ties, common currency and spatial proximity of countries. / Series: Working Papers in Regional Science

We develop and evaluate algorithms for generating random variates for simulation input. One group called automatic, or black-box algorithms can be used to sample from distributions with known density. They are based on the rejection principle. The hat function is generated automatically in a setup step using the idea of transformed density rejection. There the density is transformed into a concave function and the minimum of several tangents is used to construct the hat function. The resulting algorithms are not too complicated and are quite fast. The principle is also applicable to random vectors. A second group of algorithms is presented that generate random variates directly from a given sample by implicitly estimating the unknown distribution. The best of these algorithms are based on the idea of naive resampling plus added noise. These algorithms can be interpreted as sampling from the kernel density estimates. This method can be also applied to random vectors. There it can be interpreted as a mixture of naive resampling and sampling from the multi-normal distribution that has the same covariance matrix as the data. The algorithms described in this paper have been implemented in ANSI C in a library called UNURAN which is available via anonymous ftp. (author's abstract) / Series: Preprint Series / Department of Applied Statistics and Data Processing

Cloud computing is one important direction of current advanced technology trends, which is dominating the industry in many aspects. These days Cloud computing has become an intense battlefield of many big technology companies, whoever can win this war can have a very high potential to rule the next generation of technologies. From a technical point of view, Cloud computing is classified into three different categories, each can provide different crucial services to users: Infrastructure (Hardware) as a Service (IaaS), Software as a Service (SaaS), and Platform as a Service (PaaS). Normally, the standard measurements for cloud computing reliability level is based on two approaches: Service Level Agreements (SLAs) and Quality of Service (QoS). This thesis will focus on IaaS cloud systems’ Error Event Logs as an aspect of QoS in IaaS cloud reliability. To have a better view, basically, IaaS is a derivation of the traditional virtualization system where multiple virtual machines (VMs) with different Operating System (OS) platforms, are run solely on one physical machine (PM) that has enough computational power. The PM will play the role of the host machine in cloud computing, and the VMs will play the role as the guest machines in cloud computing. Due to the lack of fully access to the complete real cloud system, this thesis will investigate the technical reliability level of IaaS cloud through simulated virtualization system. By collecting and analyzing the event logs generated from the virtualization system, we can have a general overview of the system’s technical reliability level based on number of error events occur in the system. Then, these events will be used on neural network time series model to detect the system failure events’ pattern, as well as predict the next error event that is going to occur in the virtualization system.

Les études épidémiologiques longitudinales sur la qualité de vie (QdV) connaissent un essor depuis quelques années, surtout pour les maladies chroniques où aucun traitement curatif n'existe. L'objectif de ces études est la surveillance de la santé incluant la QdV et la survie. Une telle surveillance repose sur la comparaison de l'évolution longitudinale de QdV entre groupes de patients. Aussi, avons nous élaboré un test global de type log-rank pour l'évolution longitudinale de QdV par rapport à un taux de dégradation de QdV pour deux groupes de patients. <br />Généralement lors de ces études, des questionnaires de QdV sont donnés à remplir aux patients permettant de calculer leur score de QdV. L'évolution de QdV se traduit par le concept de dégradation de QdV. Un taux critique x de dégradation de QdV peut être fixé. Les patients sont considérés comme dégradés si leur score de QdV est supérieur à x. Nous étendons la statistique du score de vraisemblance partielle afin de prendre en compte un taux x de dégradation de QdV préalablement fixé et montrons que le vecteur du processus de score normalisé converge vers un processus gaussien centré. Le taux x de dégradation de QdV est ensuite supposé variable. A l'aide de la théorie des processus empiriques nous prouvons la convergence en distribution de la statistique du score normalisé vers un processus gaussien. Ces travaux ont permis de construire, lorsque le taux x de dégradation de QdV est variable, un test de type log-rank permettant de comparer l'évolution longitudinale de la dégradation de QdV pour deux goupes de patients.<br />Des simulations et une application à une cohorte de patients infectés par le VIH sont présentées.

Le thème central de cette thèse est l'étude et le rôle des<br />trajectoires anormales en théorie du contrôle optimal.<br /><br />Après avoir rappelé quelques résultats fondamentaux en contrôle<br />optimal, on étudie l'optimalité des<br />anormales pour des systèmes affines mono-entrée avec contrainte<br />sur le contrôle, d'abord pour le problème du temps optimal, puis<br />pour un coût quelconque à temps final fixé ou non.<br />On étend cette théorie aux<br />systèmes sous-Riemanniens de rang 2, montrant qu'on se ramène<br />à un système affine du type précédent.<br />Ces résultats montrent que,<br />sous des conditions générales, une trajectoire anormale est<br />\it{isolée} parmi toutes les solutions du système ayant les mêmes<br />conditions aux limites, et donc \it{localement optimale}, jusqu'à<br />un premier point dit \it{conjugué} que l'on peut caractériser.<br /><br />On s'intéresse ensuite<br />au comportement asymptotique et à la<br />régularité de la fonction valeur associée à un système affine<br />analytique avec un coût quadratique. On montre que, en<br />l'absence de trajectoire<br />anormale minimisante, la fonction valeur est<br />\it{sous-analytique et continue}. S'il existe une anormale<br />minimisante, on sort de la catégorie sous-analytique en général,<br />notamment en géométrie sous-Riemannienne. La présence d'une<br />anormale minimisante est responsable de la \it{non-propreté} de<br />l'application exponentielle, ce qui provoque un phénomène de<br />\it{tangence} des ensembles de niveaux de la fonction valeur par<br />rapport à la direction anormale. Dans le cas affine mono-entrée<br />ou sous-Riemannien de rang 2, on décrit précisément ce<br />contact, et on en déduit une partition de la<br />sphère sous-Riemannienne au voisinage de l'anormale<br />en deux secteurs appelés \it{secteur<br />$L^\infty$} et \it{secteur $L^2$}.\\ <br />La question de transcendance est étudiée dans le cas<br />sous-Riemannien de Martinet où la distribution est<br />$\Delta=\rm{Ker }(dz-\f{y^2}{2}dx)$. On montre que<br />pour une métrique générale graduée d'ordre $0$~:<br />$g=(1+\alpha y)^2dx^2+(1+\beta x+\gamma y)^2dy^2$,<br />les sphères de petit rayon<br />\it{ne sont pas sous-analytiques}. Dans le cas général<br />intégrable où $g=a(y)dx^2+c(y)dy^2$, avec $a$ et $c$ analytiques,<br />les sphères de Martinet appartiennent à la<br />\it{catégorie log-exp}.

Nous présentons dans cette thèse la définition, la réalisation et les tests d'un radar V.H.F. multifréquence et multipolarisation, travaillant dans une gamme allant de 20 à 100 MHz. <br />Ce système dénommé M.O.S.A.R. (Maquette Orientée pour un Système d'Analyse de Résonances) a pour objectif la mesure des sections efficaces radars d'avions dans cette gamme de fréquence, afin de fournir l'ensemble des connaissances qui permettront de concevoir un futur radar opérationnel, destiné à la détection et à l'identification des cibles aériennes.<br />Dans un premier temps, nous définissons les caractéristiques principales du système, telles que la largeur de l'impulsion émise, la période de récurrence, le nombre de fréquences utilisées, ... . Ensuite, nous construisons un radar à impulsions, monostatique, cohérent, commandé par ordinateur, capable de mesurer et d'enregistrer les signaux rétrodiffusés par des avions. Ce système emploie deux réseaux d'antennes différents pour l'émission et la réception, chacun de ces réseaux utilisant respectivement quatre antennes log-périodiques dipolaires. Les informations relatives aux cibles (amplitude, phase et fréquence Doppler) sont ensuite extraites par une analyse spectrale non linéaire haute résolution.<br />Nous évaluons les performances du radar et précisons les limites du système. Enfin, des résultats expérimentaux sont présentés et confirment les choix dans la définition et la réalisation du radar.

Cette thèse porte sur la restauration des signaux bruités observés sur des plans d'expérience aléatoires. Trois méthodes sont proposées. Dans les deux premières, on se ramène (soit par préconditionnement des données initiales, soit par régression polynomiale locale), à un problème de régression sur grille régulière. Des majorations asymptotiques de l'erreur d'estimation sont données pour les deux méthodes, sur des classes de fonctions holderiennes pour la première et sur des boules d'espaces de Besov pour la deuxième. La vitesse de décroissance de l'erreur est dans les deux cas très proche de la vitesse optimale. Un troisième algorithme concerne les plans d'expérience déterministes et utilise les ondelettes adaptées à la grille. Elles sont construites par des schémas de subdivision non réguliers, dont on étudie la convergence et les propriétés. Des nombreuses simulations et une étude comparative illustrent le comportement des trois algorithmes quand ils sont appliqués à des échantillons de taille finie.