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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.
641

La distribution et la diffusion du livre québécois dans la sphère numérique : le cas de l’Entrepôt numérique (ANEL – De Marque)

Grenier, Joanie January 2016 (has links)
En 2008, le Québec fait son entrée dans le marché du livre numérique. Cette année-là, l’Association nationale des éditeurs de livres du Québec (ANEL) s’associe avec l’entreprise De Marque pour créer l’Entrepôt numérique (www.entrepotnumerique.com), une plateforme de diffusion et de distribution de livres numériques québécois. Sa structure permet de stocker et de gérer les fichiers numériques, tout en offrant aux éditeurs une interface personnalisée afin que chacun puisse commercialiser ses titres en quelques étapes simples. Dès le départ, les instigateurs de ce projet font le pari de mettre en place une infrastructure de diffusion-distribution propre aux Québécois et qui répond à l’internationalisation du marché du livre. Mais les enjeux sont nombreux pour les professionnels du système-livre du Québec qui tentent de s’adapter aux nouvelles structures et de se frayer un chemin dans la sphère numérique. À la fois d’ordre technologique, économique et culturel, ces enjeux posent la double question de la commercialisation d’une nouvelle forme de livre et de la présence de la culture québécoise sur le web. En effet, face à la multiplication des titres et devant l’espace infini de la Toile, comment assurer la circulation et la promotion du livre numérique ? Comment adapter les circuits traditionnels à un nouveau format de livre qui se distingue de la forme fixe du livre imprimé que l’on connaît ? Et comment, surtout, la culture québécoise peut-elle prendre place auprès de géants internationaux comme Amazon, Google ou Apple ? Ayant précisément pour mandat d’offrir une solution de diffusion numérique simple et efficace aux éditeurs québécois et canadiens-français, l’Entrepôt numérique distribue la production de 148 éditeurs, donnant ainsi aux lecteurs un accès à un catalogue mutualisé comptant 17 144 publications. Plus de 750 000 livres numériques ont été vendus depuis 2009 et de nombreuses ententes de partenariat ont été signées avec 194 revendeurs provenant de 58 pays. Or, en assurant la circulation et la commercialisation des titres dans l’espace numérique, l’Entrepôt numérique participe à la mutation du secteur de la diffusion-distribution au Québec. Il illustre ainsi les évolutions techniques, économiques et structurelles du marché. S’intéresser à l’Entrepôt numérique comme objet d’étude, c’est donc s’intéresser aux enjeux (technologiques, culturels, économiques) pouvant se dégager des nouvelles stratégies de circulation et de commercialisation du livre numérique implantées au sein de la filière québécoise.  Trois chapitres composent ce mémoire. Le premier propose un historique de l’Entrepôt numérique. En décrivant à la fois les enjeux de départ, les acteurs impliqués et l’évolution de la plateforme, il permet de situer les conditions culturelles, commerciales et éditoriales ayant permis le développement de cette plateforme. Le deuxième chapitre, qui examine les mécanismes de distribution via l’Entrepôt numérique, met en lumière les différents jalons qui marquent le passage de la distribution traditionnelle à la distribution du livre numérique. Enfin, le troisième chapitre porte sur les mécanismes de diffusion du livre numérique de la plateforme et illustre ainsi les nouvelles conditions de promotion du livre dans la sphère numérique. En somme, la présentation de l’historique de l’Entrepôt numérique et l’examen des mécanismes de diffusion et de distribution de la plateforme permettent d’offrir une meilleure préhension des transformations et enjeux émanant de l’industrie du livre numérique au Québec, entre 2007 et 2015.
642

Investigation of Certain Accident Data to Determine if It Follows a Poisson Distribution and the Extent to Which It Does

Clark, Carl D. 08 1900 (has links)
The purpose of this study was to investigate the medical records of 900 maintenance personnel employed in an aircraft manufacturing plant, and determine if the accident rate followed a Poisson distribution as well as the extent to which it did. It was assumed that the closer the data conformed to the Poisson curve, the more likely it would be that the variance in accident rates was due to "pure chance factors." The investigation of data in this study was expected to reveal information concerning the relative importance of the various injury sources, the conditions, processes or activities that produce injuries, extent of recurrence of each kind of injury or accident in each type of activity or operation, repeaters, which could be utilized in preventing recurrence.
643

The Political Determinants of Fdi Location in Prchina, 1997-2009: Application of a New Model to Taiwanese Fdi in Mainland China

Lu, Kelan 08 1900 (has links)
This research seeks to identify the political determinants that account for the uneven geographical distribution of foreign direct investment (FDI) across Chinese counties. I compare the political determinants of Taiwanese FDI (TDI) and non-Taiwanese FDI site selection across counties in China. I focus on the central-local politics in China, especially the effect of county government autonomy on FDI and TDI site selection. I investigate whether the effect of county government autonomy and its interaction with TDI agglomeration varies across the three economic regions of China (i.e. eastern, central, and western regions). I argue that county government autonomy is critical to attracting inflows of FDI, and its impact is conditional on the existing level of FDI in a given county. Counties with higher autonomy are able to make greater commitments to and involvement in the market economy, have more flexibility to give preferential treatment to FDI and to improve the local investment environment. With the political burden that Taiwanese investors face from the special military and political relationship across the Strait, I argue that TDI is more sensitive to county government autonomy not only for the economic gains like other foreign investors but also for pursuing local protection against the political uncertainties from Beijing and the social instabilities of the local population. I also argue that county government autonomy’s impact on TDI inflow is strongest in the central region due to the less dominating role of the geographic and cultural advantages enjoyed by the eastern region and its better economic, cultural, political and geographic conditions that are lacking in the western region. Using the System General Method of Moment model to analyze the county level FDI/TDI panel data sets, I find autonomy’s impact on future FDI inflows fades with the increases in the existing level of FDI but gets stronger with the increases in the existing level of TDI inflows. I also find county government autonomy’s impact is strongest for the central region when the existing TDI inflows are zero or at the national average level.
644

The Interconnection of the Great Recession, Income Disparity, Segregated Metropolitan Districts, and Their Significance to All in the U.S.

Demer, Marcellus 01 January 2017 (has links)
In the United States, nobody can survive without depending on the income of oneself or of those that support them. Thus, economic opportunity and its skewed availability is pertinent to everyone. With income inequality in the United States measured in the early 2010s reaching some of the highest estimates among nations around the globe, people seek to investigate the forces behind this phenomenon and reverse it. This paper focuses on some of the many cycles and structures that exist to reinforce the challenges of achieving economic equality. Specifically, I extrapolate data to measure the correlations between the Great Recession and measures of income disparity. I then measure the effects across suburban, urban, and rural areas to highlight their differences. The paper further explains the relationship among the three, their relevance to the economy, and general directions in which organizations can circumvent the negative trends observed from the data.
645

Étude de la distribution de Salmonella spp. dans les tissus chez le porc suite à une infection naturelle et expérimentale

Côté, Sylvie January 2003 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
646

Le nématode trichostrongle Trichostrongylus axei : distribution géographique, traits de vie et résistance aux benzimidazoles / The trichostrongyle nematode Trichostrongylus axei : geographical distribution, life traits and benzimidazoles resistance

Palcy, Chrystèle 25 September 2008 (has links)
Pas de résumé fourni / No summary available
647

Incorporating geologic information into hydraulic tomography: A general framework based on geostatistical approach

Zha, Yuanyuan, Yeh, Tian-Chyi J., Illman, Walter A., Onoe, Hironori, Mok, Chin Man W., Wen, Jet-Chau, Huang, Shao-Yang, Wang, Wenke 04 1900 (has links)
Hydraulic tomography (HT) has become a mature aquifer test technology over the last two decades. It collects nonredundant information of aquifer heterogeneity by sequentially stressing the aquifer at different wells and collecting aquifer responses at other wells during each stress. The collected information is then interpreted by inverse models. Among these models, the geostatistical approaches, built upon the Bayesian framework, first conceptualize hydraulic properties to be estimated as random fields, which are characterized by means and covariance functions. They then use the spatial statistics as prior information with the aquifer response data to estimate the spatial distribution of the hydraulic properties at a site. Since the spatial statistics describe the generic spatial structures of the geologic media at the site rather than site-specific ones (e. g., known spatial distributions of facies, faults, or paleochannels), the estimates are often not optimal. To improve the estimates, we introduce a general statistical framework, which allows the inclusion of site-specific spatial patterns of geologic features. Subsequently, we test this approach with synthetic numerical experiments. Results show that this approach, using conditional mean and covariance that reflect site-specific large-scale geologic features, indeed improves the HT estimates. Afterward, this approach is applied to HT surveys at a kilometerscale- fractured granite field site with a distinct fault zone. We find that by including fault information from outcrops and boreholes for HT analysis, the estimated hydraulic properties are improved. The improved estimates subsequently lead to better prediction of flow during a different pumping test at the site.
648

Estimation non paramétrique du nombre d'espèces : Application à l'étude de la faune ichtyologique du bassin du fleuve Ouëmé / Nonparametric estimation of the number of species : application to the ichthyofauna of the Ouémé basin river

Koladjo, Babagnidé François 20 September 2013 (has links)
Ce manuscrit est structuré en deux parties. La première partie composée des chapitres 2à 4 aborde le problème d'estimation du nombre de classes dans une population avec une application en écologie. La deuxième partie, correspondant au chapitre 5,concerne la mise en oeuvre de méthodes statistiques pour analyser des données de pêche. Dans la première partie, nous considérons une population hétérogène subdiviséeen plusieurs classes. À partir d'un échantillon, les effectifs d'individus observés parclasse, encore appelés abondances, sont utilisés pour estimer le nombre total declasses dans la population. Dans la littérature consacrée à l'estimation du nombrede classes, les méthodes basées sur un mélange de distributions de Poisson semblentêtre les plus performantes (voir par exemple les travaux de Chao and Bunge (2002)dans le cadre paramétrique et celui de Wang and Lindsay (2005) dans un cadrenon paramétrique). La mise en oeuvre de ces approches sur des données réellesmet en évidence que la distribution des abondances peut être approchée par unedistribution convexe. Nous proposons une approche non paramétrique pour estimerla distribution des abondances sous contrainte de convexité. Cette contrainte définitun cadre théorique d'estimation d'une densité discrète. Le problème d'estimation dunombre de classes est donc abordé en deux volets. Nous montrons d'une part l'existenceet l'unicité d'un estimateur d'une densité discrète sous la contrainte de convexité.Sous cette contrainte, nous démontrons qu'une densité discrète s'écrit comme un mélange de densités triangulaires. À partir de l'algorithme de réduction du supportproposé par Groeneboom et al. (2008), nous proposons un algorithme exact pourestimer les proportions dans le mélange. D'autre part, la procédure d'estimationd'une densité discrète convexe nous sert de cadre pour l'estimation de la distributiontronquée en zéro des observations d'abondance. L'estimation de la loi tronquée obtenue est ensuite prolongée en zéro pour estimer la probabilité qu'une classe ne soit pasobservée. Ce prolongement en zéro est fait de façon à annuler la proportion dela première composante dans le mélange de densités triangulaires. Nousaboutissons à une estimation du nombre de classes à l'aide d'un modèle binomial ensupposant que chaque classe apparaît dans un échantillon par une épreuve deBernoulli. Nous montrons la convergence en loi de l'estimateur proposé. Sur le plan pratique, une application aux données réelles en écologie est présentée. La méthode est ensuite comparée à d'autres méthodes concurrentes à l'aide de simulations. La seconde partie présente l'analyse des données de pêche collectées dans le fleuveOuémé au Bénin. Nous proposons une démarche statistique permettant de regrouperles espèces selon leur profil temporel d'abondances, d'estimer le stock d'une espèceainsi que leur capturabilité par les engins de pêche artisanale. / This manuscript is structured in two parts. The #rst part composed of Chapters 2to 4 deals with the problem of estimating the number of classes in a population withan application in ecology. The second part, corresponding to Chapter 5, concernsthe application of statistical methods to analyze fisheries data.In the first part, we consider a heterogeneous population split into several classes.From a sample, the numbers of observed individuals per class, also called abun-dances, are used to estimate the total number of classes in the population. In theliterature devoted to the number of classes estimation, methods based on a mix-ture of Poisson distributions seem to be the most effcient (see for example the workof Chao and Bunge (2002) in the parametric framework and that of Wang and Lind-say (2005) in a non-parametric framework). Applications of these approaches to realdata show that the distribution of abundances can be approximated by a convexdistribution. We propose a non-parametric approach to estimate the distribution ofabundances under the constraint of convexity. This constraint defines a theoreticalframework for estimating a discrete density. The problem of estimating the numberof classes is then tackled in two steps.We show on the one hand the existence and uniqueness of an estimator of adiscrete density under the constraint of convexity. Under this constraint, we provethat a discrete density can be written as a mixture of triangular distributions. Usingthe support reduction algorithm proposed by Groeneboom et al. (2008), we proposean exact algorithm to estimate the proportions in the mixture.On the other hand, the estimation procedure of a discrete convex density is usedto estimate the zero-truncated distribution of the observed abundance data. Thezero-truncated distribution estimate is then extended at zero to derive an estimateof the probability that a class is not observed. This extension is made so as tocancel the first component in the mixture of triangular distributions. An estimateof the total number of classes is obtained through a binomial model assuming thateach class appears in a sample by a Bernoulli trial. We show the convergence inlaw of the proposed estimator. On practical view, an application to real ecologicaldata is presented. The method is then compared to other concurrent methods usingsimulations.The second part presents the analysis of fisheries data collected on the Ouémériver in Benin. We propose a statistical approach for grouping species accordingto their temporal abundance profile, to estimate the stock of a species and theircatchability by artisanal fishing gears.
649

Efficient double auction mechanisms in the energy grid with connected and islanded microgrids

Faqiry, Mohammad January 1900 (has links)
Doctor of Philosophy / Department of Electrical and Computer Engineering / Sanjoy Das / The future energy grid is expected to operate in a decentralized fashion as a network of autonomous microgrids that are coordinated by a Distribution System Operator (DSO), which should allocate energy to them in an efficient manner. Each microgrid operating in either islanded or grid-connected mode may be considered to manage its own resources. This can take place through auctions with individual units of the microgrid as the agents. This research proposes efficient auction mechanisms for the energy grid, with is-landed and connected microgrids. The microgrid level auction is carried out by means of an intermediate agent called an aggregator. The individual consumer and producer units are modeled as selfish agents. With the microgrid in islanded mode, two aggregator-level auction classes are analyzed: (i) price-heterogeneous, and (ii) price homogeneous. Under the price heterogeneity paradigm, this research extends earlier work on the well-known, single-sided Kelly mechanism to double auctions. As in Kelly auctions, the proposed algorithm implements the bidding without using any agent level private infor-mation (i.e. generation capacity and utility functions). The proposed auction is shown to be an efficient mechanism that maximizes the social welfare, i.e. the sum of the utilities of all the agents. Furthermore, the research considers the situation where a subset of agents act as a coalition to redistribute the allocated energy and price using any other specific fairness criterion. The price homogeneous double auction algorithm proposed in this research ad-dresses the problem of price-anticipation, where each agent tries to influence the equilibri-um price of energy by placing strategic bids. As a result of this behavior, the auction’s efficiency is lowered. This research proposes a novel approach that is implemented by the aggregator, called virtual bidding, where the efficiency can be asymptotically maximized, even in the presence of price anticipatory bidders. Next, an auction mechanism for the energy grid, with multiple connected mi-crogrids is considered. A globally efficient bi-level auction algorithm is proposed. At the upper-level, the algorithm takes into account physical grid constraints in allocating energy to the microgrids. It is implemented by the DSO as a linear objective quadratic constraint problem that allows price heterogeneity across the aggregators. In parallel, each aggrega-tor implements its own lower-level price homogeneous auction with virtual bidding. The research concludes with a preliminary study on extending the DSO level auc-tion to multi-period day-ahead scheduling. It takes into account storage units and conven-tional generators that are present in the grid by formulating the auction as a mixed inte-ger linear programming problem.
650

The utility of higher-order statistics in Gaussian noise suppression

Green, Donald R. 03 1900 (has links)
Approved for public release; distribution is unlimited. / The use of higher-order statistics provides insight into signals which is not always available at lower orders. Additionally, Gaussian-distributed signals have the interesting characteristic of disappearing at higher orders. Because so much of the noise and inter- ference environment is Gaussian-distributed, higher-order statistics thus offer the promise of an additional method of noise reduction and interference mitigation. As communica- tions signals become more and more complex, any additional ability to reduce the effects of noise and interference will have a profound impact on communications, surveillance, and intelligence systems. / US Department of Defense author (civilian).

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