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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.
81

Une approche ergonomique des sites marchands sur internet : de la perception au comportement des consommateurs

Belaud, Lydie 07 October 2011 (has links) (PDF)
L'environnement très concurrentiel de la toile détermine le contexte de la recherche. Attirer un internaute n'est pas simple et de surcroît, cela ne suffit pas puisqu'il faut ensuite qu'il devienne un consommateur fidèle qui recommandera le site marchand. La littérature a identifié certaines variables ergonomiques isolées ou semi-groupées qui auraient une influence sur l'intention comportementale, en termes d'intention d'achat, de retour, ou en termes d'intention de recommander le site, mais aucune approche satisfaisante du construit ergonomie, considéré dans sa globalité, n'est recensée dans la littérature marketing. Ce fut l'un des enjeux de cette recherche doctorale puisque nous nous sommes demandé quelle pouvait être l'influence de la perception de l'ergonomie, comprise de façon holistique, sur l'intention comportementale de l'internaute. Des allers-retours entre la littérature et les études exploratoires nous ont conduits vers des questions de recherche complémentaires. En effet, évaluer l'influence de la perception de l'ergonomie requiert de prendre en considération l'orientation motivationnelle de l'internaute, les efforts sous-jacents au traitement d'un stimulus visuel étant en partie liés à la motivation d'un individu. Par ailleurs, nous avons voulu dépasser la seule perspective cognitive pour considérer une vision plus expérientielle de la consommation. Enfin, nous avons étudié la relation qu'il pouvait y avoir entre le comportement sur le site traduit par les données logs et l'intention comportementale. Ainsi, le paradigme Personne x Objet x Situation nous a paru le mieux adapté à cette recherche doctorale en ce qu'il stipule que pour déterminer les sources ou les causes d'un phénomène il faut à la fois prendre en compte les caractéristiques de l'objet étudié, les caractéristiques de l'individu ainsi que les caractéristiques situationnelles. La circonscription et la mesure de la perception de l'ergonomie, un construit jusque-là non clairement délimité en comportement du consommateur, est l'un des apports théoriques majeurs de cette recherche. Nous avons créé un instrument de mesure court, aux propriétés psychométriques très satisfaisantes et qui est valable pour tout type de site. Le modèle structurel a montré que la perception de l'ergonomie d'un site n'aurait pas d'influence sur l'intention comportementale en ce sens où la relation serait totalement médiatisée par la dimension hédonico sensorielle. D'un point de vue managérial, cette recherche doctorale insiste sur une révision des standards ergonomiques tels qu'ils sont définis actuellement, conjointement à une meilleure prise en compte de la dimension hédonico sensorielle. Le gestionnaire de l'entreprise virtuelle s'interrogera sur un ré-enchantement du site marchand, ainsi que sur le degré de réenchantement de ce site, ce qui passera par une véritable réflexion stratégique quant au positionnement de l'enseigne et un juste équilibre entre standards ergonomiques et variables expérientielles. D'un point de vue méthodologique, nous avons souligné la complémentarité expert/utilisateur et toute la richesse d'une multiangulation des sources de données. Nous nous sommes appuyés sur des méthodologies issues d'autres disciplines comme l'oculométrie traditionnellement utilisée en IHM et qui reste peu répandue en comportement du consommateur. Nous avons montré pourquoi l'utilisation des données eye tracking pouvait se révéler particulièrement intéressante pour le chercheur, la manipulation de variables liées au design étant alors évaluée par une réponse quasi physiologique comme le temps passé sur une zone. Enfin, nous avons proposé une nouvelle méthodologie de collecte des logs avec l'utilisation du logiciel Netobserve, un outil particulièrement intéressant pour des sites non administrés par le chercheur et qui rend une relative autonomie dans le choix du terrain de recherche.
82

Energihushållning och varsamhet för äldre byggnader : Chefsbostaden i Strömsholm, ett timmerhus från 1900-talets början

Ölander, Ylva January 2014 (has links)
This report is the result of a degree project in building engineering, at an advanced level. The project evaluated a building from a technical and historical point of view, and focused on its energy consumption, particularly the energy used for heating. The building in question was a small apartment building in Strömsholm, Sweden. It was made in 1902, from vertical logs, a not so common form of the traditional log house. The goal of the project was to evaluate if the energy consumption could be reduced in accordance with building preservation regulations, that is without damaging any of the building’s cultural or historical values. The building was surveyed with the help of archive and literature studies, interviews and inspections. Based on these findings, supplementary insulation on the inner side of the climate screen was decided on. The program IDA Indoor Climate and Energy was used to make computer simulations of the energy consumption of the building for five different alternatives of supplementary insulation. Part of the project was also to investigate whether IDA Indoor Climate and Energy was suitable for energy simulations of old buildings. The moisture balance of the outer walls was calculated manually to see if the supplemental insulation constituted a risk when it came to the moisture sensitivity of the construction. The result of the computer simulations, combined with building physics, shows that the energy consumption for heating could be reduced, especially if the roof was to be insulated. However, these results cannot and should not be seen as anything but indications, because of the uncertainty of the input data. The data on ventilation and air flows was considered to be one of the main sources of error. Furthermore, there were signs that the design of the computer models was far from optimal. The result of the moisture calculations shows that the moisture sensitivity is indeed increased. IDA Indoor Climate and Energy was judged as more suitable for simulations of new buildings than of old ones, due to the complexity of the latter, but the program can still be used as an aid for energy evaluations of old buildings if it is used in the right way. / Denna rapport är resultatet av ett examensarbete i byggnadsteknik på avancerad nivå. Arbetet gick ut på att undersöka en byggnad ur ett tekniskt och kulturhistoriskt perspektiv, med inriktning på hushållning av energi. Föremålet för undersökningen var ett flerbostadshus i restimmer, uppfört 1902 i Strömsholm, Västmanland. Målet var att undersöka om byggnadstekniska åtgärder behövdes för att minska energiåtgången, främst den för aktiv uppvärmning, i byggnaden. Dessa åtgärder skulle utformas så att byggnadens bevarandevärda särdrag inte går förlorade, i enlighet med Plan- och bygglagens bestämmelser om ändring av byggnader. Med hjälp av arkivsökningar, litteraturstudier, intervjuer och undersökningar kartlades byggnaden. Utifrån dess förutsättningar bestämdes förslag för energibesparande åtgärder, fem olika alternativ för invändig tilläggsisolering. För att beräkna byggnadens energiåtgång och hur mycket de olika alternativen skulle kunna påverka denna gjordes simuleringar i programmet IDA Indoor Climate and Energy. En av frågeställningarna i arbetet var huruvida detta program var lämpligt för energisimuleringar av äldre byggnader eller inte. Beräkningar av den relativa luftfuktigheten i ytterväggen gjordes för hand för att bedöma fuktskaderisken i konstruktionen efter tilläggsisolering. Indata till fuktberäkningarna och datorsimuleringarna hämtades från litteraturen eller utgjordes av uppskattningar. Resultat av datorsimuleringarna, tillsammans med byggnadsfysiska resonemang, visar att det går att minska energiåtgången för uppvärmning, driftel och tappvarmvatten, i synnerhet vid tilläggsisolering av taket. Dock kan inte dessa resultat ses som något annat än indikationer eftersom osäkerheterna i indata för modellerna var för stora. Bristande indata för ventilationen bedömdes vara en av de största felkällorna. Dessutom föreligger vissa reservationer gällande modellernas utformning. Resultatet av fuktberäkningarna visar att väggarna blir känsliga för fuktskador vid invändig tilläggsisolering. IDA Indoor Climate and Energy bedöms vara lämpligare för simuleringar av nyproducerade byggnader än av äldre byggnader på grund av komplexiteten hos de senare, men det kan ändå fungera som ett hjälpmedelvid energiutvärderingar av sådana om det används rätt.
83

Usage-driven unified model for user profile and data source profile extraction / Model unifié dérigé par l'usage pour l'extraction du profile de l'utilisateur et de la source de donnée

Limam, Lyes 24 June 2014 (has links)
La problématique traitée dans la thèse s’inscrit dans le cadre de l’analyse d’usage dans les systèmes de recherche d’information. En effet, nous nous intéressons à l’utilisateur à travers l’historique de ses requêtes, utilisées comme support d’analyse pour l’extraction d'un profil d’usage. L’objectif est de caractériser l’utilisateur et les sources de données qui interagissent dans un réseau afin de permettre des comparaisons utilisateur-utilisateur, source-source et source-utilisateur. Selon une étude que nous avons menée sur les travaux existants sur les modèles de profilage, nous avons conclu que la grande majorité des contributions sont fortement liés aux applications dans lesquelles ils étaient proposés. En conséquence, les modèles de profils proposés ne sont pas réutilisables et présentent plusieurs faiblesses. Par exemple, ces modèles ne tiennent pas compte de la source de données, ils ne sont pas dotés de mécanismes de traitement sémantique et ils ne tiennent pas compte du passage à l’échelle (en termes de complexité). C'est pourquoi, nous proposons dans cette thèse un modèle d’utilisateur et de source de données basé sur l’analyse d’usage. Les caractéristiques de ce modèle sont les suivantes. Premièrement, il est générique, permettant de représenter à la fois un utilisateur et une source de données. Deuxièmement, il permet de construire le profil de manière implicite à partir de l’historique de requêtes de recherche. Troisièmement, il définit le profil comme un ensemble de centres d’intérêts, chaque intérêt correspondant à un cluster sémantique de mots-clés déterminé par un algorithme de clustering spécifique. Et enfin, dans ce modèle le profil est représenté dans un espace vectoriel. Les différents composants du modèle sont organisés sous la forme d’un Framework, la complexité de chaque composant y est évaluée. Le Framework propose : - une méthode pour la désambigüisation de requêtes; - une méthode pour la représentation sémantique des logs sous la forme d’une taxonomie ; - un algorithme de clustering qui permet l’identification rapide et efficace des centres d’intérêt représentés par des clusters sémantiques de mots clés ; - une méthode pour le calcul du profil de l’utilisateur et du profil de la source de données à partir du modèle générique. Le Framework proposé permet d'effectuer différentes tâches liées à la structuration d’un environnement distribué d’un point de vue usage. Comme exemples d’application, le Framework est utilisé pour la découverte de communautés d’utilisateurs et la catégorisation de sources de données. Pour la validation du Framework, une série d’expérimentations est menée en utilisant des logs du moteur de recherche AOL-search, qui ont démontrées l’efficacité de la désambigüisation sur des requêtes courtes, et qui ont permis d’identification de la relation entre le clustering basé sur une fonction de qualité et le clustering basé sur la structure. / This thesis addresses a problem related to usage analysis in information retrieval systems. Indeed, we exploit the history of search queries as support of analysis to extract a profile model. The objective is to characterize the user and the data source that interact in a system to allow different types of comparison (user-to-user, source-to-source, user-to-source). According to the study we conducted on the work done on profile model, we concluded that the large majority of the contributions are strongly related to the applications within they are proposed. As a result, the proposed profile models are not reusable and suffer from several weaknesses. For instance, these models do not consider the data source, they lack of semantic mechanisms and they do not deal with scalability (in terms of complexity). Therefore, we propose a generic model of user and data source profiles. The characteristics of this model are the following. First, it is generic, being able to represent both the user and the data source. Second, it enables to construct the profiles in an implicit way based on histories of search queries. Third, it defines the profile as a set of topics of interest, each topic corresponding to a semantic cluster of keywords extracted by a specific clustering algorithm. Finally, the profile is represented according to the vector space model. The model is composed of several components organized in the form of a framework, in which we assessed the complexity of each component. The main components of the framework are: - a method for keyword queries disambiguation; - a method for semantically representing search query logs in the form of a taxonomy; - a clustering algorithm that allows fast and efficient identification of topics of interest as semantic clusters of keywords; - a method to identify user and data source profiles according to the generic model. This framework enables in particular to perform various tasks related to usage-based structuration of a distributed environment. As an example of application, the framework is used to the discovery of user communities, and the categorization of data sources. To validate the proposed framework, we conduct a series of experiments on real logs from the search engine AOL search, which demonstrate the efficiency of the disambiguation method in short queries, and show the relation between the quality based clustering and the structure based clustering.
84

Avaliação da rigidez à flexão de toras de madeira por meio de vibração transversal / Evaluation of bending stiffness of wood logs by means of transverse vibration

Carreira, Marcelo Rodrigo 12 March 2012 (has links)
Antes de utilizar as toras de madeira como elemento estrutural é necessário avaliar as propriedades mecânicas desse material tanto por inspeção visual quanto por ensaio mecânico. A técnica de vibração transversal tem se destacado entre os demais métodos de Avaliação Não-Destrutiva para madeira serrada por obter estimativas acuradas do módulo de elasticidade à flexão. Contudo, testes prévios com essa técnica evidenciaram dificuldades de empregá-la na avaliação a rigidez à flexão de toras. O objetivo deste trabalho foi propor um método de ensaio para estimar o módulo de elasticidade na flexão de toras de madeira por meio de vibração transversal. O método proposto foi testado e validado em uma amostra de 40 toras de Eucalyptus sp. Foram obtidas boas correlações entre o módulo de elasticidade estático e o módulo de elasticidade dinâmico obtido pelo ensaio de vibração transversal. / Before using the wood logs as a structural element is necessary to evaluate the mechanical properties of this material by visual inspection and mechanical testing. The transverse vibration technique has stood out among the other methods of Non-Destructive Evaluation for lumber to obtain accurate estimates of the bending modulus of elasticity. However, previous tests showed difficulties with this technique to use it to evaluate the bending stiffness of logs. The aim of this work is to propose a test method to estimate the bending modulus of elasticity of wood logs by means of transverse vibration. The proposed method was tested and validated on a sample of 40 logs of Eucalyptus sp. It was obtained good correlation between the static bending and dynamic modulus of elasticity obtained by transverse vibration test.
85

Gender Difference in Role-Play : Male and Female Character Language in World of Warcraft

Skoglund, Jeanette January 2009 (has links)
<p>In this essay, I have investigated whether players of World of Warcraft change their language to suit the gender of the character they play. I have researched if there are gender differences that correspond to what is defined as male and female language in mixed-sex conversations. Chat-logs, collected during four participant observations, were used for making an analysis based primarily on research by Coates (1993) and Yale (2007). Seven features were selected for analysis: amount of participation, hedges, questions, directives and commands, taboo language, compliments and grammar. It was possible to discover gender differences, but these were not consistent in all areas of research. For example, female characters had a higher contribution than males, as well as a higher use of hedges and tag-questions among males, which contradicts previous research. The lack of consistency might be due to the fact that the participants do not specifically consider all areas as typically female or male, or their unawareness of these tendencies. We also need to consider disagreement in previous gender studies as well as folklinguistic belief. The explanation of the lack of consistent differences may be a more equal relationship between males and females in this context, or due to thepossibility that the participants, who are usually male, make use of their normal male language.</p>
86

Hur såg Birkas hamn ut och vilka transporter behövdes?

Wiklund, Jonas January 2009 (has links)
<p>What is located on the bottom in the water outside of Birka? Remains of a water palisade or jetties and other constructions.</p><p>Birka a Viking Age town that existed between AD 750 and 975 was located on the northwestern part of the small island of Björkö, in the Mälar archipelago of the Baltic Sea in Sweden. The Town was protected onshore by a hill fort and a town rampart. It is a widely spread assumption that Birka had a water palisade as a part of its<strong> </strong>defense. There are logs and other remnants on the bottom of the lake dating back to the Viking age. Uncertainty remains as to the origin of these remnants. The questions being, are they from a water palisade or the remnants of jetties and other constructions. The amount of fire wood alone needed to support 500 inhabitants for one year is equal to a wall of wood one meter high, one meter wide and two kilometers in length. This calculation does not take into account the wood used for transportation of other materials, people and animals. The conclusion is that future examination of the area is necessary to find out what is located on the bottom in the water.</p>
87

Comparative Study of the Chemostratigraphic and Petrophysical characteristics of Wells A-A1, A-L1, A-U1 and A-I1 in the Orange Basin, South Atlantic Margin, Offshore South Africa.

Bailey, Carlynne. January 2009 (has links)
<p>Many hydrocarbon reservoirs are situated in barren sequences that display poor stratigraphic control. Correlation between the wells can become extremely difficult and traditional correlation techniques can prove to be inadequate. Past studies have shown that trace and major element concentrations can be used as a correlation tool. This practice of using geochemical fingerprints to characterize between wells is called Chemostratigraphic analysis. (Pearce et al, 1999) Chemostratigraphy has been recognized as a very important correlation technique as it can be used for rocks of any age, in any geological setting as well as sequences that are traditionally defined as barren. Chemostratigraphic analyses can be used as a means of getting rid of ambiguities within data produced by traditional correlation methods such as Biostratigraphy, Lithostratigraphy and Geophysical Logging. In areas where stratigraphic data is not available it can be used to construct correlation frameworks for the sequences found in the area. The motivation behind this study is that the research is not only worthy of academic investigation, but can also provide the industry with new insights into areas that were previously misunderstood because traditional correlation methods were not adequate. The study area, the Orange basin, is located offshore South Africa and is largely underexplored. The basin, that hosts two gas field namely the Ibhubesi and the Kudu gas fields, has large potential but in the past has not been given due attention with only 34 wells being drilled in the area. The Orange basin has recently been the topic of investigation because of the belief that it may be hosts to more hydrocarbons. This study will utilise Chemostratigraphy to attempt to provide geological information on this relatively under-explored basin. The aim of this research study is to produce a chemostratigraphic framework -scheme for the Orange Basin in order to facilitate reservoir scale interwell correlation. The Objectives of this research study will be to identify chemostratigraphic units or indices, to prove the adequate use of chemostratigraphy as an independent correlation technique and to integrate the chemostratigraphy and petrophysical characteristics of the four wells to facilitate lithological identification.</p>
88

Hur såg Birkas hamn ut och vilka transporter behövdes?

Wiklund, Jonas January 2009 (has links)
What is located on the bottom in the water outside of Birka? Remains of a water palisade or jetties and other constructions. Birka a Viking Age town that existed between AD 750 and 975 was located on the northwestern part of the small island of Björkö, in the Mälar archipelago of the Baltic Sea in Sweden. The Town was protected onshore by a hill fort and a town rampart. It is a widely spread assumption that Birka had a water palisade as a part of its defense. There are logs and other remnants on the bottom of the lake dating back to the Viking age. Uncertainty remains as to the origin of these remnants. The questions being, are they from a water palisade or the remnants of jetties and other constructions. The amount of fire wood alone needed to support 500 inhabitants for one year is equal to a wall of wood one meter high, one meter wide and two kilometers in length. This calculation does not take into account the wood used for transportation of other materials, people and animals. The conclusion is that future examination of the area is necessary to find out what is located on the bottom in the water.
89

Reservoir description with well-log-based and core-calibrated petrophysical rock classification

Xu, Chicheng 25 September 2013 (has links)
Rock type is a key concept in modern reservoir characterization that straddles multiple scales and bridges multiple disciplines. Reservoir rock classification (or simply rock typing) has been recognized as one of the most effective description tools to facilitate large-scale reservoir modeling and simulation. This dissertation aims to integrate core data and well logs to enhance reservoir description by classifying reservoir rocks in a geologically and petrophysically consistent manner. The main objective is to develop scientific approaches for utilizing multi-physics rock data at different time and length scales to describe reservoir rock-fluid systems. Emphasis is placed on transferring physical understanding of rock types from limited ground-truthing core data to abundant well logs using fast log simulations in a multi-layered earth model. Bimodal log-normal pore-size distribution functions derived from mercury injection capillary pressure (MICP) data are first introduced to characterize complex pore systems in carbonate and tight-gas sandstone reservoirs. Six pore-system attributes are interpreted and integrated to define petrophysical orthogonality or dissimilarity between two pore systems of bimodal log-normal distributions. A simple three-dimensional (3D) cubic pore network model constrained by nuclear magnetic resonance (NMR) and MICP data is developed to quantify fluid distributions and phase connectivity for predicting saturation-dependent relative permeability during two-phase drainage. There is rich petrophysical information in spatial fluid distributions resulting from vertical fluid flow on a geologic time scale and radial mud-filtrate invasion on a drilling time scale. Log attributes elicited by such fluid distributions are captured to quantify dynamic reservoir petrophysical properties and define reservoir flow capacity. A new rock classification workflow that reconciles reservoir saturation-height behavior and mud-filtrate for more accurate dynamic reservoir modeling is developed and verified in both clastic and carbonate fields. Rock types vary and mix at the sub-foot scale in heterogeneous reservoirs due to depositional control or diagenetic overprints. Conventional well logs are limited in their ability to probe the details of each individual bed or rock type as seen from outcrops or cores. A bottom-up Bayesian rock typing method is developed to efficiently test multiple working hypotheses against well logs to quantify uncertainty of rock types and their associated petrophysical properties in thinly bedded reservoirs. Concomitantly, a top-down reservoir description workflow is implemented to characterize intermixed or hybrid rock classes from flow-unit scale (or seismic scale) down to the pore scale based on a multi-scale orthogonal rock class decomposition approach. Correlations between petrophysical rock types and geological facies in reservoirs originating from deltaic and turbidite depositional systems are investigated in detail. Emphasis is placed on the cause-and-effect relationship between pore geometry and rock geological attributes such as grain size and bed thickness. Well log responses to those geological attributes and associated pore geometries are subjected to numerical log simulations. Sensitivity of various physical logs to petrophysical orthogonality between rock classes is investigated to identify the most diagnostic log attributes for log-based rock typing. Field cases of different reservoir types from various geological settings are used to verify the application of petrophysical rock classification to assist reservoir characterization, including facies interpretation, permeability prediction, saturation-height analysis, dynamic petrophysical modeling, uncertainty quantification, petrophysical upscaling, and production forecasting. / text
90

Död ved och förekomsten av två mossor som indikerar skoglig kontinuitet / Dead wood and the presence of two mosses indicating forest continuity

Flink, Maria January 2011 (has links)
Studiens syfte är att undersöka arterna Buxbaumia viridis och Nowellia curvifolia för att kunna förutse var man hittar dessa signalarter. Detta gjordes genom att död liggande ved undersöktes i Ycke naturreservat samt en närliggande brukas skog, Östergötlands län. Resultaten visar att faktorerna som är avgörande för B. virids är markkontakt och nedbrytningsklass. B. viridis föredrar att växa på lågor i de högre nedbrytningsklasserna (4-7) och med stor andel markkontakt, över 80 %. N. curvifolia beror på diameter (över 60cm), nedbrytningsklass (3-4) och längd (över 30m). Baserat på dessa resultat, kan signalarter lättare upptäckas utan en fullskalig inventering av skogen. / Young trees dominate Swedish forests, which today have a shortage of downed dead wood, key biotopes, and an overall lack of high natural values. By using the mosses Buxbaumia viridis and Nowellia curvifolia the general state of a forest can be assessed. These species indicate high natural values, with a continuity of dead wood in different stages of decay. By investigating ground-lying dead wood, one can predict if the mosses occur in the area or not. This is useful for maintenance of the forests and the preservation of biological diversity. The purpose of this study was to study the species B. viridis and N. curvifolia in Ycke natural reserve in Östergötland, southern Sweden, and learn how to predict where these species occur. The results showed that ground contact (over 80 %) and stage of decay (stage 4-6) of logs were important to B. viridis, with test values 30- 50 times as high as the other test values. To N. curvifolia, the diameter of the logs was the most important. Decay stage and length of the log were also important factors to N. curvifolia. Based on these results, these indicator species can more easily detected without a full scale inventory of the forest.

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