Dans de nombreuses industries, les producteurs doivent passer par des intermédiaires afin de distribuer leurs produits sur les marchés. Par exemple, dans le secteur de la grande distribution alimentaire, les producteurs vendent leurs produits à des distributeurs qui ont un accès direct aux consommateurs finaux; dans les secteurs de la santé, les fournisseurs de soins médicaux (e.g., les hôpitaux) traitent avec les assureurs afin d’avoir accès aux patients. Toutes ces industries sont souvent caractérisées par une structure oligopolistique bilatérale avec un petit nombre d'entreprises opérant sur les deux côtés du marché, impliquant des relations commerciales complexes entre les acteurs. En effet, les externalités contractuelles sont omniprésentes dans ce type d’environnement puisque la valeur générée par une transaction et partagée entre un fabricant et un détaillant dépend généralement des décisions contractuelles des autres entreprises opérant sur le marché. Un certain nombre de pratiques, communément appelées « restrictions verticales », peuvent également survenir, telles que des contrats d'exclusivité, des pratiques de ventes liées, ou bien des fixations de prix de revente. En outre, les conditions tarifaires sont principalement déterminées par un processus de négociation entre les entreprises. L’objet de ma recherche consiste à analyser comment les relations verticales entre entreprises dans un contexte aussi complexe que celui des oligopoles bilatéraux peuvent avoir un impact sur le surplus du consommateur et le bon fonctionnement de l’industrie. Dans le premier chapitre de ma thèse, j’élabore un modèle d’économétrie structurelle afin d’analyser empiriquement les relations producteur- distributeur dans des oligopoles bilatéraux avec produits différenciés. L’approche contraste avec la plupart des méthodes empiriques antérieures et permet d’identifier la division du surplus entre les entreprises sans la nécessité d’avoir des données sur les contrats de gros et les coûts marginaux des firmes. Le deuxième chapitre se concentre sur l’étude des effets générés par la formation d’alliances entre distributeurs pour négocier des tarifs communs et acheter des produits auprès de leurs fournisseurs. En utilisant des données d’achats sur les eaux embouteillées réalisés par un panel de consommateurs représentatif de la population Française, j'estime un modèle structurel de demande et d'offre. Je réalise ensuite des simulations pour étudier les effets de trois alliances formées par des distributeurs dans le secteur de la distribution alimentaire en France. Les résultats montrent que le pouvoir de négociation des distributeurs est affaibli, le profit total de l'industrie diminue, et que les consommateurs finaux font face à des prix plus élevés. Le troisième chapitre de cette thèse analyse la pratique du «full-line forcing» comme mécanisme d’éviction sur les marchés verticalement liées. Je considère un modèle dans lequel un producteur multi-produit offre une marque leader et une marque secondaire sur laquelle il est en concurrence avec une entreprise plus efficace. Le modèle permet de mettre en évidence que le « full-line forcing » est une stratégie de négociation efficace car elle permet au producteur multi-produit d’influer sur les points de menace dans les négociations et d’imposer son portefeuille de marques sur les étagères du distributeur, excluant ainsi le producteur concurrent. Cette stratégie émerge à l’équilibre sous trois conditions : (i) la marque leader de l’entreprise multi-produit est suffisamment forte, (ii) son inefficacité sur la marque secondaire n’est pas trop sévère, et (iii) le fournisseur concurrent est assez puissant dans sa négociation avec le distributeur. Les résultats suggèrent que les consommateurs finaux et le bien-être total peuvent être réduit alors que, dans certains cas, le distributeur bénéficie d’une telle stratégie d’éviction. / In many economic environments, producers need to deal with intermediaries to supply their products on markets. Examples include grocery markets in which food manufacturers sell their products to retailers who have direct access to final consumers; pharmaceutical industries where manufacturers distribute their drugs on markets through drugstores; multichannel television industries where cable channels sell their programs to multichannel video program distributors who then charge fees to consumers; private healthcare sectors in which medical providers (e.g., hospitals) deal with insurers to have access to sick patients. One particular feature of such industries is that they are often characterized by a bilateral oligopolistic structure with a small number of firms operating on both sides of the market, resulting in complex vertical relationships. Contracting externalities are indeed intrinsic to such environments because the value generated by a transaction and shared between a manufacturer and a retailer generally depends on the contracting decisions of other firms operating on the market. A number of practices, commonly referred to as vertical restraints, may also arise such as exclusive dealing, bundling and tying, resale price maintenance, or quantity discounts. Furthermore, trading terms are mostly determined through a bargaining process between upstream and downstream firms rather than being fixed by one-side of the market. My research consists in analyzing how vertical relationships between firms in such complex settings impact consumer surplus and total welfare. To this end, I rely on both theoretical models and empirical methods to derive predictions of the effects of contractual arrangements within the supply chain. In the first chapter of this dissertation I design a structural framework to analyze manufacturer-retailer relationships in bilateral oligopolies with differentiated products. Our approach contrasts with most prior empirical models of bargaining and allows to identify the division of surplus between firms without data on wholesale contracts and marginal costs. The second chapter investigates the economic effects of alliances formed by retailers to negotiate common prices and purchase products from manufacturers. I use household- level scanner data on bottled water purchases and estimate a structural model of demand and supply. I perform simulations to study the economic effects of three buyer alliances that have been formed by competing retailers in the French food retail sector. Results show that the bargaining power of retailers is weakened, total industry profit decreases, and final consumers face higher prices. The third chapter examines the case of full-line forcing as a foreclosure device in vertically related markets. We consider a setting in which a multi-product manufacturer offers a leading brand and a secondary brand for which it competes with a more efficient single-product firm. We show that full-line forcing is an efficient bargaining strategy as it allows the multi-product manufacturer to affect threat points and impose its brand portfolio on the retailer’s shelves therefore excluding the rival supplier. This strategy arises in equilibrium under three conditions (i) the leading brand of the multi- product firm is strong enough, (ii) the inefficiency on the secondary brand is not too severe, and (iii) the rival supplier is powerful enough in its bargaining with the retailer. Our results suggest that final consumers and total welfare may be harmed whereas, in some cases, the retailer benefits from such a foreclosure strategy.

No description available.

The implementation and application of Geographic Information Systems (GIS) and spatial analyses have become standard practice in many archaeological projects. In this study, we demonstrate how GIS can play a crucial role in the study of taphonomy, i.e., understanding the processes that underpinned the creation of archaeological deposits, in this case the distribution of artifacts across an archeological site. The Stelida Naxos Archeological Project (SNAP) is focused on the exploration of a Paleolithic-Mesolithic stone tool quarry site located on the island of Naxos, Greece. An extensive pedestrian survey was conducted during the 2013 and 2014 archeological field seasons. An abundance of lithic material was collected across the surface, with some diagnostic pieces dating to more than 250 Kya. Spatial statistical analysis (Empirical Bayesian Kriging) was conducted on the survey data to generate predictive distribution maps for the site. This study then determined the contextual integrity of the surface artifact distributions through a study of geomorphic processes. A digital surface model (DSM) of the site was produced using Unmanned Aerial Vehicle (UAV) aerial photography and Structure from Motion (SfM) terrain modeling. The DSM employed to develop a Revised Universal Soil Loss Equation (RUSLE) model and hydrological flow models. The model results provide important insights into the site geomorphological processes and allow categorization of the diagnostic surface material locations based on their contextual integrity. The GIS analysis demonstrates that the surface artifact distribution has been significantly altered by post-depositional geomorphic processes, resulting in an overall low contextual integrity of surface artifacts. Conversely, the study identified a few areas with high contextual integrity, loci that represent prime locations for excavation. The results from this study will not only be used to inform and guide further development of the archeological project (as well as representing significant new data in its own right), but also contributes to current debates in survey archaeology, and in mapping and prospection more generally. This project demonstrates the benefit of using spatial analysis as a tool for planning of pedestrian surveys and for predictive mapping of artifact distributions prior to archaeological excavations. / Thesis / Master of Science (MSc)

[pt] O gerenciamento da cadeia de suprimento (GCS) recebeu muita atenção de acadêmicos e praticantes da indústria no que tange a grandes empresas. Contudo, existe uma carência de estudos do GCS focados em pequenas empresas. Isto se faz necessário em função das diferenças entre as realidades de grandes e pequenas empresas, implicando na dificuldade de aproveitar o conhecimento acumulado já existente de GCS para as pequenas empresas, e na importância que as pequenas empresas têm para a economia de diversos países, em particular as emergentes, como a Brasileira. Neste contexto, a presente dissertação de mestrado tem como objetivo avançar no conhecimento do GCS em pequenas empresas por meio da análise de práticas de GCS em empresas no Estado do Rio de Janeiro (Brasil). As práticas analisadas nesta pesquisa são gestão de relacionamento com o cliente, práticas de gerenciamento de operações, planejamento e processos de negócios e gestão do relacionamento com fornecedores. A metodologia adotada é composta de três etapas, as quais visam através da adoção das quatro abordagens do MIT GeneSys coletar dados acerca do perfil do gerente e da empresa, das práticas de negócios utilizadas pela empresa, mapear os ativos da empresa, verificar quais práticas de GCS são utilizadas, determinar quais atividades e quanto tempo o tomador de decisões gasta nelas e em quais atividades ele gasta mais tempo. Sendo consolidada nessa dissertação a assessoria dada às empresas, pois após todo o processo da coleta de dados foi realizado um feedback à empresa, através de uma apresentação dos resultados com as recomendações. Como resultado, a dissertação oferece um guia prático para implementar e gerir com sucesso práticas de GCS em pequenas empresas, o qual está disponível para que as empresas possam utilizar. / [en] Supply chain management (SCM) has received a lot of attention from academics and industry practitioners when it comes to large companies. However, there is a shortage of SCM studies focused on small enterprises. This is necessary due to the differences between the realities of large and small enterprises, resulting in the difficulty of harnessing the existing accumulated knowledge of SCM for small enterprises, and the importance that small enterprises have for the economy of various countries, particularly emerging ones, such as the Brazilian. In this context, this master dissertation aims to advance the knowledge of SCM in small enterprises by analyzing SCM practices in enterprises in the State of Rio de Janeiro (Brazil). The practices analyzed in this research are customer relationship management, operations management practices, planning and business processes and supplier relationship management. The methodology adopted consists of three stages, which aim to adopt the four approaches of MIT GeneSys to collect data about the profile of the manager and the company, the business practices used by the company, map the company s assets, verify which practices of SCM are used, determining which activities and how much time the decision maker spends on them and on what activities he spends the most time. The advice given to the companies was consolidated in this dissertation, since after the entire data collection process, a feedback was made to the company, through a presentation of the results with the recommendations. As a result, the dissertation provides a hands-on guide for successfully implementing and managing small enterprises SCM practices, which is available for the companies to use.

The purpose of this study is to explore if the use of virtual reality (VR) improves performance in sports and examine whether there is empirical evidence supporting this. There is a lack of a common denominator that can be used as a direct comparison between various studies. Construct validity, the degree of which a method and test accurately trains and assesses what is required on the sports field, could be this link. A scoping review of empirical research evidence, using methodology adapted to the field of engineering, was conducted. This review sourced articles from two databases, PubMed and Scopus. The selection process was conducted according to PRISMA, using specific selection criteria. A total of 23 articles were analysed. An absolute majority of the examined articles (74%) demonstrated that VR is an effective tool in boosting performance of participants in the respective studied sports. Martial arts and ball sports are the sports utilising VR technology the most in our sample, the studies examining these sports demonstrate positive performance outcomes of VR training. The results of this scoping review clearly demonstrates that there is empirical evidence that VR technology is used in a variety of sports to train and test important performance factors. For the future, more controlled studies should examine causal relationships between VR training and subsequent outcomes to further assess VR technology and its effect on sports performance. Studies should consider using tests and VR training methods that are as close to real world equivalent training methods in sports as possible in order to improve construct validity. The level of construct validity could be evaluated through a score system (0-10), which can be used to directly compare the quality of the studies examining VR as a tool for training and performance between sports. / Syftet med denna studie är att utvärdera användningen av virtual reality (VR) som ett medel för att förbättra prestationen inom sport och om det finns empiriska bevis som stödjer detta. VR har potentialen att förbättra prestationen inom olika sporter för amatörer såväl som elitidrottare oberoende av väder och vind samt geografiska restriktioner. En scoping-review genomfördes, med metodik adapterad till ingenjörsvetenskap. Sökningen utfördes via sökmotorer PubMed och Scopus. Det saknas en gemensam nämnare som kan användas som ett jämförelsemått mellan de olika studierna. Begreppsvaliditet, i vilken utsträckning en test och träningsmetod är tillämpbar för att träna och mäta prestationsförmågan på fältet, kan vara ett sådant mått. 23 artiklar valdes ut med stöd av inklusions och exklusionskriterier med PRISMA-metodik. En absolut majoritet av de utvalda artiklarna (74 %) påvisade att VR var ett effektivt verktyg för att höja prestationsförmågan hos försökspersonerna inom sina respektive sporter. Kampsport och bollsporter är de mest populära sporterna som använder VR-teknik inom vårt urval, studierna som publicerats i dessa sporter visar positiva utfall av VR träning. Sammanfattningsvis finns det empiriska bevis som visar att VR teknologi används i en rad olika sporter för träning och test av olika faktorer för att förbättra prestationsförmågan i respektive idrott. Denna scoping-review visar att VR-träning förbättrar prestationsförmågan i en majoritet av utvärderade artiklar. För framtiden finns ett behov av att studier studerar kausala samband mellan VR träning och utfall för att förbättra VR teknologin och dess påverkan på idrottsprestationer. Studier bör anpassas så att tester och träning är så lika som möjligt till verkliga idrottsprestationer för att förbättra begreppsvaliditeten och kanske göra denna faktor till ett mått/score (0-10) som kan användas för att kunna jämföra kvaliteten av studier kring effekten av VR träning mellan olika idrotter.

The Mechanistic-Empirical Pavement Design Guide (MEPDG) which is widely used for the rational design of pavements has three different design levels (i.e., Level 1, Level 2, and Level 3) that are typically based on the resources and the level of risk associated for a given project. Specifically, Level 2 design requires the estimation of the resilient modulus, MR (which is the key parameter in the mechanistic design procedures) from simple experiments such as the California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS) and R-value tests. In this study, a technique is proposed for estimation of MR from CBR that can be used in Level 2 designs of pavements. The California Bearing Ratio (CBR) is a relatively inexpensive laboratory test which provides a measure of the strength of a soil. The CBR test can easily be performed as the experimental procedure is relatively straightforward to execute. The CBR test procedure widely used and is simple, however the fundamental engineering principles governing CBR tests do not realistically describe the mechanical behavior of pavements. Due to this reason, there has been a significant interest to design pavements using a mechanistic approach such as the resilient modulus (MR). The MR test method provides an indication of the stiffness of pavement materials under cyclic loads, which closely represents the typical loading conditions that are experienced by pavements. MR is a reliable method as it considers the cyclic loading (i.e., resilient response) of pavements. However, it has one major drawback as the triaxial testing equipment used for measurement of the MR is relatively costly, testing is complex and requires trained professional to perform them. The CBR and MR are both used in present day practice to evaluate the strength of pavement materials. However, the CBR is widely used because of its relatively low cost and the vast experience with its use in the design of pavements. The common trend in today’s practice is to estimate the MR from CBR as evident in most pavement design procedures used around the world. For instance, the Mechanistic-Empirical Pavement Design Guide (AASHTO 2008) suggests that the MR may be estimated from standard tests like the CBR for design of Level 2 pavements. Numerous studies in the literature propose relationships between CBR and MR, but only a hand full of these studies takes account of the effect of matric suction, 𝜓 which is a key stress state variable that describes the rational behavior of unsaturated soils. This thesis document includes the explanation of a modified CBR test equipment capable of measuring unsaturated properties (𝜓 and water content) of specimens subjected to wetting and drying. In addition, some correlations were developed using the measured CBR data and the data of MR from other studies. The results provide useful information for Level 2 mechanistic-empirical design of pavement structures for various soils in the province of Ontario.

No description available.

We first consider confidence intervals for a normal percentile, an exponential percentile and a uniform percentile. Then we develop confidence intervals for a difference of percentiles from two independent normal populations, two independent exponential populations and two independent uniform populations. In our study, we mainly focus on the maximum likelihood to develop our confidence intervals. The efficiency of this method is examined via coverage rates obtained in a simulation study done with the statistical software R.

Characterization of the seismic hazard and ground-failure hazard of a site using traditional empirical lateral spread displacement models requires consideration of uncertainties in seismic loading, site conditions, and model prediction. Researchers have developed performance-based design methods to simultaneously account for these sources of uncertainty through the incorporation of a probabilistic analytical framework. While these methods can effectively handle the various sources of uncertainty associated with empirical lateral spread displacement prediction, they can be difficult for engineers to perform in a practical manner without the use of specialized numerical tools. To make the benefits of a performance-based approach accessible to a broader audience of geotechnical engineers, a simplified performance-based procedure is introduced in this paper. This map-based procedure utilizes a reference soil profile to provide hazard-targeted reference displacements across a geographic area. Equations are provided for engineers to correct those reference displacements for site-specific soil conditions and surface geometry to produce site-specific, hazard-targeted estimates of lateral spread displacement. The simplified performance-based procedure is validated through a comparative study assessing probabilistic lateral spread displacements across several cities in the United States. Results show that the simplified procedure closely approximates the results from the full performance-based model for all sites. Comparison with deterministic analyses are presented, and the place for both in engineering practice are discussed.

In an effort to increase both the quality of software applications and the efficiency with which applications can be written, developers often incorporate multiple programming languages into software projects. Although language specialization arguably introduces benefits, the total impact of the resulting language fragmentation (working concurrently in multiple programming languages) on developer performance is unclear. For instance, developers may solve problems more efficiently when they have multiple language paradigms at their disposal. However, the overhead of maintaining efficiency in more than one language may outweigh those benefits. This thesis represents a first step toward understanding the relationship between language fragmentation and programmer productivity. We address that relationship within two different contexts: 1) the individual developer, and 2) the overall project. Using a data-centered approach, we 1) develop metrics for measuring productivity and language fragmentation, 2) select data suitable for calculating the needed metrics, 3) develop and validate statistical models that isolate the correlation between language fragmentation and individual programmer productivity, 4) develop additional methods to mitigate threats to validity within the developer context, and 5) explore limitations that need to be addressed in future work for effective analysis of language fragmentation within the project context using the SourceForge data set. Finally, we demonstrate that within the open source software development community, SourceForge, language fragmentation is negatively correlated with individual programmer productivity.