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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.
551

微小重力下での直線燃料液滴列に沿った火炎伝ぱ (第1報, 液滴間火炎伝ぱ様式マップの作成)

梅村, 章, UMEMURA, Akira 08 1900 (has links)
No description available.
552

Les ressources annotées, un enjeu pour l'analyse de contenu : vers une méthodologie de l'annotation manuelle de corpus

Fort, Karën 07 December 2012 (has links) (PDF)
L'annotation manuelle de corpus est devenue un enjeu fondamental pour le Traitement Automatique des Langues (TAL). En effet, les corpus annotés sont utilisés aussi bien pour créer que pour évaluer des outils de TAL. Or, le processus d'annotation manuelle est encore mal connu et les outils proposés pour supporter ce processus souvent mal utilisés, ce qui ne permet pas de garantir le niveau de qualité de ces annotations. Nous proposons dans cette thèse une vision unifiée de l'annotation manuelle de corpus pour le TAL. Ce travail est le fruit de diverses expériences de gestion et de participation à des campagnes d'annotation, mais également de collaborations avec différents chercheur(e)s. Nous proposons dans un premier temps une méthodologie globale pour la gestion de campagnes d'annotation manuelle de corpus qui repose sur deux piliers majeurs : une organisation des campagnes d'annotation qui met l'évaluation au cœur du processus et une grille d'analyse des dimensions de complexité d'une campagne d'annotation. Un second volet de notre travail a concerné les outils du gestionnaire de campagne. Nous avons pu évaluer l'influence exacte de la pré-annotation automatique sur la qualité et la rapidité de correction humaine, grâce à une série d'expériences menée sur l'annotation morpho-syntaxique de l'anglais. Nous avons également apporté des solutions pratiques concernant l'évaluation de l'annotation manuelle, en donnant au gestionnaire les moyens de sélectionner les mesures les plus appropriées. Enfin, nous avons mis au jour les processus en œuvre et les outils nécessaires pour une campagne d'annotation et instancié ainsi la méthodologie que nous avons décrite.
553

Molecular Phylogeography and Species Discrimination of Freshwater <em>Cladophora</em> (Cladophorales, Chlorophyta) in North America

Ross, Sara J. January 2006 (has links)
<em>Cladophora</em> is a widespread freshwater filamentous cholorophyte genus and is frequently observed in eutrophic waters where it can produce large nuisance blooms. These blooms can have direct impacts on water intake for power generation, irrigation canals and can be aesthetically unpleasant. Much of the ecological and physiological studies on <em>Cladophora</em> have assumed that the populations of this genus in North America belong to the species <em>Cladophora glomerata</em>. However, this has never been tested despite that it is well documented that identifying freshwater <em>Cladophora</em> to the species level is difficult due morphological variability under different ecological conditions. In addition, the species epithets for freshwater <em>Cladophora</em> are based on European collections and it is not clear if these should be applied to North America. This study examines approximately 40 collections of <em>Cladophora</em> from the Laurentian Great Lakes and 43 from various locations in North America ranging from the Northwest Territories to Puerto Rico. Initially we determined the nucleotide sequences of the internal transcribed spacer (ITS) region of the nuclear ribosomal cistron and observed sequence divergence to be low (0-3%), demonstrating an inability for this marker to resolve species delineation as divergence of this region was low. Amplification of the inter-simple sequence repeat (ISSR) regions were used to analyze microsatellite motif frequency throughout the genome to evaluate the biogeography relationships, including diversity, of freshwater <em>Cladophora</em> sp. five different primers were used on 70 individuals. UPGMA analyses of the presence/absence of bands demonstrate that each of the Great Lake populations separate into groups according to the Lake they were initially sampled from. However, collections from North America are highly variable and do not form well supported biogeographic clades. In addition, these collections appear to be distinct from type cultures of freshwater <em>Cladophora</em> from Europe. Supplementary morphological analysis using suggested taxonomically valid criterion (length and diameter of main axis, ultimate branch, and apical cell) none were able to differentiate Great Lake populations.
554

Social Network Theory in Inter-Organizational Alliances: An Exploratory Examination of Mobile Payments Engagement

Hazzard-Robinson, Deborah D 05 May 2012 (has links)
Fueled by ubiquitous access to mobile phones, and a massive population of nearly 3 billion unbanked people around the globe, mobile commerce is evolving as a disruptive technology. Simultaneously, mobile payments are surfacing as a killer application within the mobile commerce context (Hu et al. 2008). Undeniably, the proliferation of wireless mobile technology provides much-needed access to vital information, and financial services for disenfranchised, unbanked populations. In addition, technological innovations offer first-time opportunities for suppliers of goods and services in a market context to gain competitive advantages while enhancing their economic viability. According to Portio Research, the volume of mobile payments rose significantly from $68.7 billion U.S. dollars in 2009, with predictions of $633.4 billion U.S. dollars by the end of 2014 (mobithinking.com 2012). Despite exponential growth in the number of mobile subscribers globally, and widespread adoption of mobile commerce, acceptance rates for mobile payment applications have lagged (Dahlberg et al. 2007, Ondrus et al 2009, Ondrus and Lyytinen 2011). Yet examinations of factors inhibiting the widespread acceptance of mobile payments are relatively sparse. Using Social Network theory, this research examines factors affecting engagement in mobile payments. The researcher posits that four primary elements influence mobile payment engagement: 1) the relationships between and amongst inter-organizational alliance members; 2) the prevailing regulatory environment; 3) the state of existing banking and technology infrastructures, and 4) an assessment of economic opportunity. The research outcomes from this exploratory examination led to the development of a comprehensive model for mobile payment engagement, and strongly suggest that ties between and amongst firms in inter-organizational alliances help ensure the success of mobile payment engagement. Support was found for the following suppositions: 1) similarities and relations (continuous ties) help establish a framework and understanding amongst alliance members as to each party’s goals and objectives; and 2) interactions and flows (discrete ties) between and amongst inter-organizational alliance members strengthen the overall ties between alliance members while solidifying a viable working relationship amongst the alliance members. This study employs a qualitative approach to obtain real world insight into the dynamism of the mobile payment arena. A model is then proposed to practically examine mobile payment engagement opportunities. From a theoretical perspective, the research contributes to the extant scholarly knowledgebase pertaining to engagement in mobile payments.
555

Behavior Modeling of a Digital Video Broadcasting System and the Evaluation of its Equalization Methods

Jian, Wang, Yan, Xie January 2010 (has links)
In this thesis, a single carrier ATSC DTV baseband transmitter, part of the receiver(including channel estimator and channel equalizer), were modeled. Since multi-pathinduced ISI (inter symbol interference) is the most significant impact on theperformance of single carrier DTV reception, modeling and implementation of singlecarrier channel estimator and channel equalizer have been the focus of the thesis. Westarted with the investigation of channel estimation methods. Afterwards, severalchannel estimators and equalizers were modeled and the performance of each channelequalization methods in different scenarios was evaluated. Our results show that thefrequency domain equalizer can achieve low computing cost and handle long delaypaths. Another important issue to be considered in block equalization is Inter-BlockInterference (IBI). The impact of IBI was investigated via behavior modeling. In lastpart of our thesis, two methods for IBI cancellation are compared and the proposal forhardware implementation was given.
556

How to manage flexibility and control in interfirm R&amp;D collaborations? : A study of knowledge integration between companies in the explorative phase of innovation

Lindberg, Hanna, Rinstad, Henrik January 2011 (has links)
Background and problem: There are a number of benefits that can be gained from an inter-firm R&amp;D collaboration, however it is at the same time a challenging task. An important factor to achieve a sucessful R&amp;D collaboration is the knowledge integration between the companies. Handling the two problems of cooperation and coordination are key to this success and can be done by using different mechanisms. These mechanisms suggest that the increasing degree of problems with cooperation and coordination requires increased control. As a result, an interesting aspect is how to manage the contradiction between control of knowledge integration and the need for flexibility which are both necessary for the explorative phase of an innovation process. Objective: The purpose of this thesis is to explore how an inter-firm R&amp;D collaboration in the explortive phase of innovation can manage the knowledge integration contradiction of flexibility and control. Method: To fulfill our purpose we have made a ethnographically inspired case study on an inter-firm R&amp;D collaboration in the explorative phase of innovation. Definitions: Knowledge integration: Taking advantage of specialists’ knowledge that exists in collaboration. Inter-firm R&amp;D collaboration: A partnership between external companies undertaking research and developing something together. The explorative phase of innovation: The early phase before the architecture of the innovation has been set. Conclusion: Our results indicate that a loose structure, high trust, bigness as a source of power, vertical collaboration, close collaboration and limited size of the collaboration are mechanisms that the collaborators use to manage the contradiction between flexibility and control in the explorative phase of innovation.
557

Cooperation in the distribution channel : Determinants of inter-organisational cooperation between suppliers and servicing dealers in the Swedish outdoor power equipment market

Magnusson, Jonas, Olsson, Johan, Risom, Benjamin January 2011 (has links)
Background: For manufacturing suppliers, careful handling of business relationships with dealers is an essential function required for business success. End consumers rely on dealers for product information, advice and after sales support; all of which being factors capable of enhancing their perceived value of the product. The importance of the dealers for the end consumers implies that it is in the interest of suppliers to manage their relationship with the dealers in a satisfactory manner in order of gaining their support and commitment. In the case of suppliers in the Swedish market for outdoor power equipment, managing this relationship with servicing dealers is of great importance to their business success and viability. Successful management of such relationships requires coordination and cooperation. Thus, it is in the interest of suppliers to understand how long-term cooperation with dealers can be enhanced. Purpose: Our research focuses on identifying determinants that enhance sustainable cooperation between manufacturers and servicing dealers in the Swedish outdoor power equipment market. Method: A survey was conducted among servicing dealerships in Sweden testing eight hypotheses developed through an adaption of Morgan and Hunts’ (1994) Commitment-trust theory together with an extensive literature review. The results were ana-lysed and tested with correlation analysis. Conclusions: Trust and commitment were found to be determinants in fostering sustainable cooperation between dealers and manufacturers in the Swedish market for outdoor power equipment. Furthermore, four important antecedents for dealer commitment were identified; supplier commitment, support, termination costs and participation. Whereas, communication was found to be an important precursor for trust.
558

Self-Organizing Wireless Sensor Networks For Inter-Vehicle Communication

Iqbal, Zeeshan January 2006 (has links)
Now a day, one of the most attractive research topics in the area of Intelligent Traffic Control is Inter-vehicle communication (V2V communication). In V2V communication, a vehicle can communicate to its neighbouring vehicles even in the absence of a central Base Station. The concept of this direct communication is to send vehicle safety messages one-to-one or one-to- many vehicles via wireless connection. Such messages are usually short in length and have very short lifetime in which they must reach the destination. The Inter-vehicle communication system is an ad-hoc network with high mobility and changing number of nodes, where mobile nodes dynamically create temporary sensor networks and transferring messages from one network to others by using multiple hops due to limitation of short range. The goal of the project is to investigate some basic research questions in order to organize such sensor networks and at the same time highlight the appropriate routing protocol that support mobile ad hoc networks in an efficient and reliable manner. In our investigation, we have answered the technical issues in order to construct a V2V communication system. We have also studied some mobile ad hoc network routing protocols in detail and then selected the DSR (Dynamic Source Routing) for our V2V communication and then simulated it according to our system requirements. We are quite satisfied by the result of DSR, but at the same time much more work is required to come up with an absolute application for the end user.
559

Molecular Phylogeography and Species Discrimination of Freshwater <em>Cladophora</em> (Cladophorales, Chlorophyta) in North America

Ross, Sara J. January 2006 (has links)
<em>Cladophora</em> is a widespread freshwater filamentous cholorophyte genus and is frequently observed in eutrophic waters where it can produce large nuisance blooms. These blooms can have direct impacts on water intake for power generation, irrigation canals and can be aesthetically unpleasant. Much of the ecological and physiological studies on <em>Cladophora</em> have assumed that the populations of this genus in North America belong to the species <em>Cladophora glomerata</em>. However, this has never been tested despite that it is well documented that identifying freshwater <em>Cladophora</em> to the species level is difficult due morphological variability under different ecological conditions. In addition, the species epithets for freshwater <em>Cladophora</em> are based on European collections and it is not clear if these should be applied to North America. This study examines approximately 40 collections of <em>Cladophora</em> from the Laurentian Great Lakes and 43 from various locations in North America ranging from the Northwest Territories to Puerto Rico. Initially we determined the nucleotide sequences of the internal transcribed spacer (ITS) region of the nuclear ribosomal cistron and observed sequence divergence to be low (0-3%), demonstrating an inability for this marker to resolve species delineation as divergence of this region was low. Amplification of the inter-simple sequence repeat (ISSR) regions were used to analyze microsatellite motif frequency throughout the genome to evaluate the biogeography relationships, including diversity, of freshwater <em>Cladophora</em> sp. five different primers were used on 70 individuals. UPGMA analyses of the presence/absence of bands demonstrate that each of the Great Lake populations separate into groups according to the Lake they were initially sampled from. However, collections from North America are highly variable and do not form well supported biogeographic clades. In addition, these collections appear to be distinct from type cultures of freshwater <em>Cladophora</em> from Europe. Supplementary morphological analysis using suggested taxonomically valid criterion (length and diameter of main axis, ultimate branch, and apical cell) none were able to differentiate Great Lake populations.
560

R-D Optimal Scalable Video Coding Using Soft Decision Quantization

Hebel, Krzysztof Michal 17 November 2010 (has links)
In this thesis, we study the concept of scalable video coding as implemented in the extension to the H.264 video coding standard. Specifically, for the spatial and quality scalability scenarios, we propose an optimization algorithm based on the Soft Decision Quantization (SDQ) concept, which aims at jointly optimizing all layers being encoded. The performance of the algorithm was assessed in an SVC implementation. Experimental results show, that the proposed method significantly improves the coding efficiency when compared to an unmodified SVC encoder.

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