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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.
661

Hodnocení kvality gastronomických služeb / Gastronomic services quality evaluation

Kosová, Michaela January 2008 (has links)
The thesis is focused on gastronomic services quality evaluation. The theoretical section characterizes gastronomy, its particularities and gives an overview of legal regulations covering this area. Furthermore, it explains the concept of quality, outlines the basic quality management systems, specifies the particularities of quality in gastronomic services and elucidates possible attitudes towards gastronomic services quality evaluation and recognition. The analytical section presents an analysis of the situation in the field of gastronomic services quality evaluation in Germany and in the Czech Republic and is focused on gastronomic guides, internet evaluation portals and restaurant databases. It also mentions the approach to the unified classification or quality standardization in this branch and introduces a short comparison of selected statistical indicators. The final part of the thesis proposes own simple system of catering establishment standardization and quality certification in the Czech Republic.
662

Les modes de plasmon sur film métallique ondulé, appliqués aux documents de sécurité / Plasmon modes applied to the Optical Document Security

Sauvage-Vincent, Jean 22 October 2013 (has links)
La présente thèse se propose de résoudre les problématiques de facilités de contrôle optique d’un document de sécurité pourvu d’un hologramme par l’application d’une structure optique complexe mettant en œuvre les modes de plasmons de surface. Dans une partie dédiée nous démontrerons l’adaptation de la transmission extraordinaire plasmonique à travers une couche métallique continue ; un concept de sécurité sera aussi présenté permettant l’observation et l’authentification de l’effet transmissif. Dans une autre partie nous présentons un effet de réflexion plasmonique extraordinaire. En lieu et place des phénomènes classiques d’absorption sur une couche métallique épaisse, nous présentons un phénomène que nous avons nommé balance énergétique à médiation plasmonique. Cet effet est bien évidemment mis en évidence à travers un concept final adapté au domaine de l’optique de sécurité / The aim of this PhD thesis is to find optical solutions based on plasmon modes excitation for the control and the authentication of optical security documents. We developed complex optical structures for the excitation of plasmon modes in order to create “easy to catch” and “easy to check" effect. In the first part of the thesis we demonstrated the extraordinary optical transmission through a thin corrugated metallic layer using the Long range plasmon mode; a concept of optical document security is demonstrated. In a second part of the thesis we developed an unusual plasmon effect in reflexion. Instead of having absorption of the spectrum due to the plasmon excitation, we have reflection of the spectrum due to the plasmon excitation using higher diffracted orders. We call this effect "reflection switch" mediated by plasmon. At the end we developed the concept to an optical security document
663

Contribution à la caractérisation de l’anglais de l’alpinisme, par l’étude du domaine spécialisé des guides de haute montagne états-uniens / Contribution to the Characterization of Mountaineering English as Specialized Discourse. The Case of American Mountain Guides

Wozniak, Séverine 25 November 2011 (has links)
Cette thèse en anglais de spécialité s’inscrit dans le champ de l’étude des domaines spécialisés et de leurs discours en contexte anglophone. La recherche entreprise contribue à la caractérisation de l’anglais de l’alpinisme par l’étude du domaine spécialisé des guides de haute montagne états-uniens. Dans cet objectif, nous élaborons un modèle de caractérisation des domaines spécialisés et de leurs discours et nous le testons. La première partie présente notre cadre théorique et notre méthodologie de recherche. Elle s’ouvre par une réflexion épistémologique sur la posture du chercheur et sur son objet de recherche, avant de s’intéresser à l’approche du domaine spécialisé, puis au cadre méthodologique. La deuxième partie aborde la caractérisation du domaine spécialisé en contexte états-unien. Elle débute par une perspective historique sur l’alpinisme aux États-Unis. La communauté professionnelle des guides de haute montagne et les enjeux de leur pratique professionnelle font ensuite l’objet d’une analyse. La troisième partie propose une caractérisation des discours du domaine spécialisé de l’alpinisme. Nous identifions tout d’abord les outils mobilisables pour l’analyse des discours spécialisés, avant d’entreprendre une analyse terminologique de l’anglais de l’alpinisme et de tenter de dresser une typologie des genres du discours spécialisé écrit. / This dissertation focuses on English for Specific Purposes and, more particularly, on the study and characterization of specialized professional domains and their discourses in English-speaking countries. It is a contribution to the characterization of mountaineering English, via the study of the specialized domain of American mountain guides. To this end, a model for the characterization of specialized domains and their discourses was designed and tested. Part 1 presents the theoretical and methodological framework of this research. It begins with an epistemological reflection on the status of the researcher and his/her object, and then moves on to the description of the process by which specialized domains can be studied, based on a consideration on the methodological framework, and more particularly, on the nature and value of fieldwork. Part 2 focuses on the characterization of the specialized professional domain of mountain guiding and begins with a historical account of mountaineering in the US. It deals with the training and work of professional mountain guides and aims to identify and analyze the stakes for the profession today. Part 3 attempts to characterize the discourse of mountaineering and mountain guiding. Some features of this specialized discourse are discussed, from a terminological point of view, and finally, a typology of the different written genres of the specialized discourse is proposed.
664

Analyse et conception de répéteurs passifs plans à rayonnement quasi-latéral pour communications «indoor» à 60GHz / Analysis and design of planar passive repeaters with quasi-endfire radiation for 60GHz indoor communications

Wang, Duo 06 May 2015 (has links)
Le développement rapide de l’industrie des systèmes sans fil suscite une demande urgente pour des communications à haut débit, notamment en environnement « indoor ». Toutefois, les protocoles traditionnels de communications sont incapables de supporter de très hauts débits et, surtout, il n'y a pas de ressources spectrales disponibles à basse fréquence. Comme une alternative, la bande des 60GHz est préconisée parce qu’elle permet un débit de plus de 5Gbit/s, grâce à son large spectre (57GHz à 64 GHz). Toutefois, en pratique, l’environnement « indoor » est complexe et, dans les situations d’absence de visibilité directe, la couverture radio est difficile à assurer à cause des fortes atténuations. Afin de remédier à ce problème, l’utilisation de répéteurs est possible. Dans cette thèse, l’intérêt est porté sur les répéteurs passifs, plus simples à installer et compatibles avec une réalisation faible coût. Le cas critique de la couverture radio d’un couloir en T est choisi comme fil conducteur, tout au long de cette étude. Les solutions préconisées visent aussi la compacité, ce qui justifie l’utilisation de réflecteurs plans. A partir de la théorie des réseaux d’antennes, une structure périodique générique pour le répéteur est proposée. Elle implique deux cellules réfléchissantes élémentaires (espacées de /2), produisant des ondes en opposition de phase. Plusieurs topologies et technologies sont ensuite envisagées et étudiées pour la mise en oeuvre. La première utilise des antennes à résonateur diélectrique (DRA). Deux topologies différentes sont étudiées et comparées, le DRA à encoche et le DRA couplé à une ligne déphaseuse en circuit ouvert. Différentes stratégies de modélisation sont également étudiées en utilisant une cellule unique, un couple de 2 cellules avec phases opposées ou un petit réseau. Pour chaque topologie, un réseau canonique de 6×6 éléments est simulé. La deuxième technologie étudiée utilise des guides d’ondes rectangulaires chargés par un matériau diélectrique et courtcircuités. Des analyses paramétriques sont effectuées et un 6 ×6 réseau est conçu et optimisé pour valider la faisabilité de la solution. Finalement, une structure en guide à plaques métalliques parallèles est analysée. Dérivant de la solution précédente, elle permet une fabrication plus simple. Pour cette dernière solution, une analyse plus complète est menée incluant des considérations sur la bande passante, les performances en incidence oblique et la direction de rayonnement maximal. Enfin, un réseau à base de cet élément rainuré est fabriquée présentant une taille de 200 mm×200 mm. Des mesures expérimentales à 60GHz sont réalisées pour tester les performances du réseau. La preuve de concept est ainsi donnée et les résultats expérimentaux sont analysés. / The fast development of information and consumer electronics industries creates a pressing demand for high-speed indoor communications. Traditional communication protocols are unable to support such high transmission rate, and there are no radio bands available at lower frequency. As an alternative, 60GHz communications have sparked great attention, since it enables a maximum data transmission rate more than 5Gbit/s based on its wide unlicensed bandwidth. However, practical indoor environment is usually complicated (e.g. walls, corridors, stairs, etc.), thus the non-line-of-sight (NLOS) areas cannot be covered due to the significant attenuation. Considering the requirements for signal recovery in the NLOS environment, a planar passive repeater with endfire radiation and high directivity, low profile and low cost is investigated and designed in this thesis. Based on array theory, a periodic structure for the foreseen printed repeater is derived out. It involves two reflector elements (in the spacing of 2) to provide 0° and 180°reflection phases respectively. In order to construct a proper reflector element, four topologies are proposed and analyzed. In the first part of the study, DRA (Dielectric Resonator Antenna) technology is the main focus. Two different topologies are investigated and compared, including notched DRA and DRA coupled to phase-shift stub. Different modeling strategies are also studied using either a single cell, a couple of cells with opposite phases or a small array. For each topology, a preliminary 6×6 array is simulated. Optimization at the array level is emphasized through the whole thesis. In the second part, investigations are taken on a rectangular dielectric filled waveguide element. Parametric analyses are carried out and possible fabrication technologies are discussed. Once again, a preliminary 6×6 array is designed and optimized to validate the feasibility of such a structure. In the third part, a parallel-plate groove structure is analyzed. It evolves from the rectangular waveguide, and enjoys more simplification. Further work is taken to explore the arrays’ bandwidth, oblique incidence performance and maximum radiation direction. Detailed theoretical analysis based on the simulation results are demonstrated in the end. Finally, an array based on the groove elements is fabricated in the size of 200mm×200mm. Practical measurements for 60GHz communications in NLOS environment are designed to test the array’s performance. Analyses on the experiment results are given.
665

Planejamento da operação energetica via curvas-guias de armazenamento / Hydrothermal scheduling with storage guide-curves

Zambelli, Monica de Souza 31 July 2006 (has links)
Orientadores: Secundino Soares Filho, Marcelo Agusto Cicogna / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-07T21:19:01Z (GMT). No. of bitstreams: 1 Zambelli_MonicadeSouza_M.pdf: 1476300 bytes, checksum: 26436b0b3c9bd918ebd703de827d4906 (MD5) Previous issue date: 2006 / Resumo: O setor elétrico brasileiro vem passando por sucessivas reformas na busca por um modelo institucional que permita a otimização do uso dos recursos energéticos, conciliada com o objetivo de se alcançar um desenvolvimento sustentável. O planejamento energético tem um papel fundamental neste contexto, de modo que estudos e pesquisas que forneçam suporte ao planejamento do setor energético e à elaboração de políticas energéticas de médio e longo prazo têm ganhado destaque entre as prioridades do setor elétrico brasileiro. A proposta deste trabalho é apresentar uma política operativa baseada no conceito de curvas-guias de armazenamento para o planejamento da operação energética de médio prazo. Essa política determina que, a cada estágio do período de planejamento, as decisões de vazão turbinada por cada usina hidrelétrica devem ser tais que mantenham seus reservatórios em níveis pré-estabelecidos por curvas-guias de armazenamento. A análise de desempenho dessa política operativa foi feita através de simulações da operação hidrotérmica, para sistemas de único reservatório e uma cascata do sistema elétrico brasileiro. Os resultados das simulações foram também comparados aos de políticas operativas mais robustas, incluindo o uso de programação dinâmica estocástica, técnica de solução já consolidada para o problema e utilizada atualmente no setor elétrico brasileiro. Os resultados demonstram que, apesar de simples e transparente, essa política operativa apresenta um desempenho competitivo para o planejamento da operação energética / Abstract: The Brazilian electric sector has been passing through successive reforms in the search for an institutional model that allows the optimization of the use of the energetic resources, concealed with the goal of achieving a sustaining development. The energetic planning plays a fundamental roll in this context, thus studies and researches designated to support planning in the energetic sector and elaboration of long term energetic policies have been gaining space among the Brazilian electric sector priorities. The proposal of this work is to present an operating policy based on the concept of storage guide-curves for the mid term hydrothermal scheduling. This policy determines that, at each stage of the planning period, the decisions of water discharged from each hydro plant must be such that keep their reservoirs at levels pre-determined by storage guide-curves. The performance analysis of this operating policy was done through operation simulation, considering different hydro plants of the Brazilian system. The simulation results were also compared to more robust operative policies, including the use of stochastic dynamic programming, a consolidated solution technique for the problem witch is actually in use by the Brazilian electric sector. The results demonstrate that, despite of simple and transparent, this operating policy presents a competitive performance for the hydrothermal scheduling / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica
666

Successful outcomes of adult ex-offenders: "Catalyst to Change"

Crowley-Ames, Coleen, McNeal, Phyllis Paulette 01 January 2003 (has links)
This descriptive, statistical survey research design sought to identify factors that motivate individuals to stay crime free after serving time in prison. The purpose of this research study was to examine the factors that played a significant role in recidivism.
667

Persuasive Chatbot Conversations : Towards a Personalized User Experience

Rönnberg, Sofia January 2020 (has links)
Helping drivers improve their driving skills and become safer drivers is a problematic topic. Most drivers have a lacking self-assessment ability and consider themselves above average driving skills. This is believed to be related to the lack of continuous feedback after getting the driver’s license. This has led to initiatives to find alternative ways of coaching drivers toward better self-assessment and thereby toward safer driving. Chatbots and conversational interfaces has received increasing attention over the years and could be technologies that can solve these challenges. However, a major challenge to chatbots is that they are mostly implemented in a “one-size-fits-all” approach, and while personalization of the chatbot could solve that challenge, it ishard to achieve. In this study, personalized chatbot conversations that aim to coach drivers are examined. The aim is to create a guide that can help designers and practitioners with design decisions that needs to be considered when creating coaching chatbot conversations. The study was performed as a Wizard of Oz study, where attributes for personalization as well as coaching considerations were tested with users in two iterations to iteratively develop the guide. The findings of the study include the guide itself with its guidelines (see appendix 4), as well as insights on considerations required chatbot personalization and coaching. Regarding personalization, chatbot personality and level of control were identified as two attributes that were fit for adaptation. These can lead to social benefits as well as more tailored services to the users. For coaching, the use of follow-ups, feedback and the chatbot’s attitude are identified as necessary considerations when designing coaching chatbot conversations.
668

Drum Music: A Performance Guide and Discussion of John Mackey's Influential Concerto for the Modern Percussionist

McWilliams, Chris 08 1900 (has links)
John Mackey is an influential and prolific composer of wind band literature. His focus on and exploration of the percussion section are defining characteristics of his compositional voice. Mackey's concerto for percussion and wind band, "Drum Music," is a perfect example of his exploitation of the myriad timbres available within the percussion family, and also serves to showcase the versatility required of a modern percussionist. This dissertation and accompanying lecture recital provide a comprehensive guide for performers of the work. Major aspects of Mackey's compositional approach are discussed with emphasis placed on his use of percussion throughout his works. Analysis and performance concerns are discussed for each of the concertos three movements, and information is provided on the reduced version of the work prepared as part of this study.
669

Traditional Korean Music in Contemporary Context: A Performance Guide to Gideon Gee Bum Kim's Kangkangsullae

Lee, Hyejin 05 1900 (has links)
Gideon Gee Bum Kim is an internationally-acclaimed contemporary Korean-Canadian composer. Kim has utilized traditional Korean music with Western composition techniques in some of his works. Kim created his own style by incorporating traditional Korean musical elements such as the scale, rhythmic diversity, syncopation, variation, ornamentation, and the progression of melody into a body of music that is otherwise contemporary and Western. The purpose of this study is to develop a performance guide for Gideon Gee Bum Kim's Kangkangsullae for string trio. Kangkangsullae trio is based on Korean historical, cultural and musical influences. I give a detailed historical and cultural background for this work and demonstrate how Kim integrated Western compositional techniques with traditional Korean music. My emphasis is on defining specific characteristics of traditional Korean music which will provide several points toward understanding Kim's compositional style.
670

Unorthodox Pianism and Its Unexpected Consequences: A Performance Guide to Leo Ornstein's Seventeen Waltzes

Kharitonov, Arsentiy 05 1900 (has links)
Leo Ornstein's most significant piano oeuvre, the Seventeen Waltzes, stand out as a unique example of a pianism as a foundation for the composer's musical thoughts. The purpose of this document is to provide musical and technical suggestions based on Ornstein's pianistic patterns, which will help pianists understand the composer's complex writing and form a coherent interpretation. The guide covers the main avant-garde musical devices used by Ornstein such as tone clusters, polymeter, and polyrhythm. A comparison process within the collection will help performers to address Ornstein's unmarked waltzes by underlining the composer's similar ideas and traits.

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