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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

Bridging the Theory-to-practice Gap: a Multivariate Correlational Study Exploring the Effects of a Graduate Online Learning Environment As a Community of Practice Framework

Bone, Tonda Jenean 12 1900 (has links)
In this multivariate correlational study, the researcher examined the course culture of an online graduate course whose environment exhibited characteristics of a Community of practice (CoP). An online survey captured data used to explore the relationships among variables shown to describe a CoP in field environments and among student perceptions of their experience in the course culture. A canonical correlation analysis (CCA) and commonality analysis (CA) were conducted using five predictor variables and three criterion variables to evaluate the degree and direction of the relationships. The CCA revealed that the full model was significant, explaining approximately 74% of the variance among the two synthetic variates. Impact, faculty leadership, and connection were the largest contributors to the predictor variate. The criterion variate was primarily explained by value and perceived CoP, with exposure to the profession providing a smaller contribution. The CA confirmed these findings. Results from this study indicate that a CoP could be fostered in an online graduate course. The overall significance of the model indicates teachers can nurture an environment wherein graduate students will take the initiative to work with others to create and acquire knowledge that creates a sense of professional connection with each other and with the profession overall. The results of this study suggest further empirical research in implementing and assessing CoPs in online graduate courses is warranted.
82

Antecedents and Impacts of Knowledge Management Practices Supported by Information Technology: An Empirical Study in Manufacturing Context

Muhammed, Shahnawaz 06 September 2006 (has links)
No description available.
83

Interação, Redes e comunidades de Prática (CoP): subsídios para a Gestão do Conhecimento na Educação / Interaction, Networks and Communities of Practice (CoP): basis for Knowledge Management in Education

Mengalli, Neli Maria 04 October 2006 (has links)
Made available in DSpace on 2016-04-27T14:31:55Z (GMT). No. of bitstreams: 1 CED - Neli Maria Mengalli.pdf: 1133453 bytes, checksum: 9b37542e06a79f0d5775441d5827b224 (MD5) Previous issue date: 2006-10-04 / This Master s Dissertation researches the disclosures derived from the curriculum of the School Administrators Development course in the use of Information and Communication Technologies of the School Administration and Technology Project, which emerged from the actions, practices, attitudes and discourse of the educational administrators from the public schools of Sao Paulo State and departments of education. These disclosures made explicit certain indications of knowledge based management through technological resources that empower the development of collaborative actions. Considering that the computer is a potential instrument for creating communities, the research shows the possible uses of technological resources for network building, problem solving, and decision making. Data collection instruments consisted of the forums and reflective memoirs written by the course participants in various roles; semi structured interviews with project members and instructors selected after review of the memoirs; and questionnaires regarding the topic of knowledge based management. After data analysis and interpretation, it was possible to perceive indications of knowledge based management in the schools, yet still enacted intuitively and unsystematically. Although the course project included the elements indicated by theorists as essential to knowledge based management, not all of these concepts were revealed in the data collection instruments. It was possible to perceive the potentials for the suggestion of network formation and community building, primarily Communities of Practice (CoP), as the basis for knowledge based management in Education. / A presente Dissertação de Mestrado pesquisa os desvelamentos derivados do currículo do curso Formação de Gestores Escolares para o uso das Tecnologias de Informação e Comunicação do Projeto Gestão Escolar e Tecnologias, que emergiram das ações, das práticas, das atitudes e dos discursos dos gestores educacionais que atuavam nas escolas da rede pública de São Paulo e nas diretorias de ensino. O desvelado explicitou indícios de gestão baseada no conhecimento por meio de recursos tecnológicos potencializadores do desenvolvimento de ações colaborativas. Sendo o computador um instrumento potencial para a criação de comunidades, a pesquisa procurou mostrar as possibilidades de uso dos recursos tecnológicos para a formação de redes, resolução de problemas e tomada de decisão. Os instrumentos de coleta de dados foram os fóruns e memoriais reflexivos, escritos por participantes do curso em diferentes papéis; entrevistas semi-estruturadas, realizadas com integrantes e formadores do projeto, selecionados após a leitura dos memoriais; e questionários acerca do assunto gestão baseada no conhecimento. Após a análise e interpretação dos dados, foi possível perceber indícios de gestão baseada no conhecimento em escolas, porém feitos ainda de modo intuitivo e sem sistematização. Embora o projeto do curso pesquisado tivesse trabalhado os elementos apontados por teóricos como essenciais para a gestão baseada no conhecimento não foram desveladas todas as noções nos instrumentos de coletas de dados. Foi possível perceber as potencialidades para a sugestão de formação de redes e criação de comunidades, principalmente a Comunidade de Prática (CoP), como subsídios para a gestão baseada no conhecimento na Educação.
84

Funktionelle Genomanalyse des Purinverwerters Clostridium acidurici 9a / Functional genome analysis of the purine-utilizing bacterium Clostridium acidurici 9a

Hartwich, Katrin 05 December 2012 (has links)
No description available.
85

Vėdinimo įrenginių su integruotais šilumos siurbliais projektavimas, tyrimas ir analizė / Design, Research and Analysis of Air Handling Units with Air Source Heat Pumps

Bareika, Paulius 20 June 2013 (has links)
Magistro baigiamajame darbe nagrinėjami vėdinimo įrenginiai su integruotais šilumos siurbliais. Darbe atliekama tokios rūšies įrenginių literatūros apžvalga. Apžvelgiami šilumos siurblio komponentai, darantys didžiausią įtaką jo darbui. Darbo metu atlikti įrenginių projektavimo ir konstravimo darbai. Pateikiamos projektavimo rekomendacijos. Lyginami skirtingi kompresorių galios moduliacijos principai. Nagrinėjami įrenginių darbo režimai, kylančios problemos eksploatacijos metu, ieškomi problemų sprendimų būdai. Pateikiamos kintamo sukimosi greičio kompresorių galių moduliacijos ribos. Atliekamos energinė ir ekserginė analizės pagal eksperimentinio bandymo duomenis. Nustatomi realūs termodinaminio efektyvumo ir naudingumo koeficientai. Jautrumo analizės metu atliekami elektrinio šildytuvo efektyvumo ir naudingumo skaičiavimai. Pateikiami rezultatai, išvados ir rekomendacijos tokios rūšies įrenginių tobulinimui ir tolimesniam vystymui. Darbo apimtis – 94 psl. teksto be priedų, 66 iliustr., 7 lent., 43 bibliografiniai šaltiniai. / Master's thesis examines air handling units with integrated air source heat pumps. Literature review about this type of units was carried out. An overview of mostly important heat pump‘s components are given. Thesis was an opportunity to design, construct and analyze these units. Different heat pump‘s operation modes examined and main issues turned out. Based on experimental data variable speed compressor's capacity modulation results defined. Moist air thermodynamic calculations have been made and air handling unit with integrated air source heat pump experimental energy and exergy efficiency was defined. Sensitivity evaluation changing heat pump with electric heater carried out. The main recommendation provided for units designing and further development. Thesis consist of 94 p. text without appendixes, 66 pictures, 7 tables, 43 bibliographical entries.
86

Resetting International Law Linkages: COP 20 Mechanisms and Protocols / Reinicializando los Vínculos del Derecho Internacional: Mecanismos y Protocolos de la COP 20

Ferrey, Steven 10 April 2018 (has links)
The article reviews the experiences of programs to promote renewable energy in Southeast Asian countries and proposes some learned lessons that can be useful in the context of COP 20 to promote renewable energy.The article analyzes the rates and mechanisms of promotion used in countries such as India, Indonesia and Vietnam, that are led by the World Bank. These mechanisms are used as a legal basis that proposes successful tested alternatives and its usefulness is that renewable energies can be implemented within the current legal structure of international environmental law.In conclusion, it is the correct timing for the COP 20 to secure funds and international legal mechanisms that promote sustainable energy infrastructure. / El presente artículo revisa las experiencias de programas de promoción de energías renovables en países del sudeste asiático a fin de proponer algunas lecciones aprendidas que puedan ser útiles en el contexto de la Vigésima Conferencia de las Partes de la Convención Marco de las Naciones Unidas sobre el Cambio Climático (COP 20) para la promoción de las energías renovables. Asimismo, revisa las tarifas y mecanismos de promoción utilizados en India, Indonesia y Vietnam, impulsados por el Banco Mundial, como una base para proponer alternativas legales ya probadas. Su utilidad es que las energías renovables pueden ser implementadas dentro de la estructura legal actual del Derecho Ambiental Internacional, la COP 20 es el momento de asegurar fondos y mecanismos jurídicos internacionales que promueven una infraestructura energética sostenible.
87

Le jeu de policiers-voleur sur différentes classes de graphes

Turcotte, Jérémie 12 1900 (has links)
Réalisé avec le support financier du Conseil de recherches en sciences naturelles et en génie du Canada (CRSNG) et du Fonds de Recherche du Québec – Nature et technologies (FRQNT). / Ce mémoire étudie le jeu de policiers-voleur et contient trois articles, chacun portant sur une classe de graphes spécifique. Dans le premier chapitre, la notation et les définitions de base de la théorie de graphe qui nous serons utiles sont introduites. Bien que chaque article comporte une introduction citant les concepts et résultats pertinents, le premier chapitre de ce mémoire contient aussi une introduction générale au jeu de policiers-voleur et présente certains des résultats majeurs sur ce jeu. Le deuxième chapitre contient l’article écrit avec Seyyed Aliasghar Hosseini et Peter Bradshaw portant sur le jeu de policiers-voleurs sur les graphes de Cayley abéliens. Nous améliorons la borne supérieure sur le cop number de ces graphes en raffinant les méthodes utilisées précédemment par Hamidoune, Frankl et Bradshaw. Le troisième chapitre présente l’article concernant le cop number des graphes 2K2-libres. Plus précisément, il est prouvé que 2 policiers peuvent toujours capturer le voleur sur ces graphes, prouvant ainsi la conjecture de Sivaraman et Testa. Finalement, le quatrième chapitre est l’article écrit avec Samuel Yvon et porte sur les graphes qui ont cop number 4. Nous montrons que tous ces graphes ont au moins 19 sommets. En d’autres mots, 3 policiers peuvent toujours capturer le voleur sur tout graphe avec au plus 18 sommets, ce qui répond par la négative à une question de Andreae formulée en 1986. Un pan important de la preuve est faite par ordinateur; ce mémoire contient donc une annexe comprenant le code utilisé. / This thesis studies the game of cops and robbers and consists of three articles, each considering a specific class of graphs. In the first chapter, notation and basic definitions of graph theory are introduced. Al- though each article has an introduction citing the relevant concepts and results, the first chapter of this thesis also contains a general introduction to the game of cops and robbers and presents some of its major results. The second chapter contains the paper written with Seyyed Aliasghar Hosseini and Peter Bradshaw on the game of cops and robbers on abelian Cayley graphs. We improve the upper bound on the cop number of these graphs by refining the methods used previously by Hamidoune, Frankl and Bradshaw. The third chapter presents the paper concerning the cop number of 2K2-free graphs. More precisely, it is proved that 2 cops can always catch the robber on these graphs, proving a conjecture of Sivaraman and Testa. Finally, the fourth chapter is the paper written with Samuel Yvon which deals with graphs of cop number 4. We show that such graphs have at least 19 vertices. In other words, 3 cops can always catch the robber on any graph with at most 18 vertices, which answers in the negative a question by Andreae from 1986. An important part of the proof is by computer; this thesis thus has an appendix containing the code used.
88

Analyse biomécanique et électromyographique des éléments d'anticipation de l'initiation de déplacement en fauteuil roulant manuel / Biomechanics and electromyographic analysis of anticipation elements of the manual wheelchair initiation displacement

Chikh, Soufien 19 June 2015 (has links)
Les Personnes à Mobilité Réduite (PMR) souffrent souvent de limitation au cours de la locomotion. Plusieurs outils sont à leurs dispositions pour les aider et les assister dans leur déplacement, plus particulièrement le Fauteuil Roulant Manuel (FRM) ou électrique. Ces travaux de thèse se focalisent sur les interactions entre le sujet et le FRM afin de déterminer des éléments prédictifs du déplacement à venir dans l’optique d’une aide à la locomotion. Comprendre l'Interaction Homme-FRM (IHF) est un enjeu actuel afin d'améliorer le déplacement et d’optimiser la performance ainsi que le confort, en minimisant la fatigue et les risques des blessures. Pour contribuer à mieux comprendre voire améliorer cette IHF, un ensemble d'études centrées sur une analyse biomécanique et électromyographique des éléments d'anticipation de l'Initiation du Déplacement en FRM (ID-FRM) a été réalisé au cours de ces travaux de thèse. Cet ensemble d’études porte sur i) les Activités Musculaires Anticipatoires (AMA) en position assise pour interroger la prédictibilité des mouvements au regard de ses paramètres préalables ; ii) l’évolution des patterns musculaires et des pressions sur l'assise lors de l'ID-FRM, pour interroger l’adaptabilité ou la spécificité des paramètres initiaux lors de différents déplacements en FRM chez des sujets valides. ; iii) l’évolutions des patterns musculaires et des pressions sur l'assise lors de l'ID-FRM chez des sujets blessés médullaires et ; iv) l’analyse multi-variée des paramètres de l'ID-FRM. Le SNC présente des capacités d'adaptabilité importantes au mouvement à venir en ajustant les commandes motrices aux conditions physiologiques globales du sujet. Cette adaptabilité a conduit à des pourcentages importants de prédiction et elle peut être enregistrée au travers d'éléments macroscopiques permettant d'envisager des systèmes d'aide au déplacement, notamment pour les PMR. / People with Disabled Mobility (PDM) often suffer from limitation during locomotion. Several tools are at their disposal to help and assist them in their displacement, specifically the electric or the Manual Wheelchair (MW). This thesis works focuses on the Human-MW-Interaction (H-MW-I) subject to determine elements predictors of forthcoming displacement with a view of aid to locomotion. Understanding (H-MW-I) is a current challenge to improve the displacement and optimize the performance as well as comfort, by minimizing fatigue and injury risk. In order to enhance understanding and even improving the (H-MW-I), a set of studies focusing on Biomechanics and electromyographic analysis of anticipation elements of the Manual Wheelchair Initiation Displacement (MW-ID) was performed during the thesis works. This set of studies focuses on i) Anticipatory Muscular Activities (AMA) in the sitting position to question the predictability of the movements in relation to its prior parameters; ii) evolution of muscular patterns and pressures on the seat when MW-ID to question the adaptability or specificity of the initial parameters during various displacements using MW in healthy subjects ; iii) evolution of muscular patterns and pressures on the seat when MW-ID in spinal cord injury subjects and; iv) multivariate analysis of the MW-ID parameters. The CNS presents an important capacity of adaptability to the forthcoming movement by adjusting motor commands to the global physiological condition of the subject. This adaptability has led to significant percentages prediction and it can be saved through macroscopic elements to envisage help systems to displacement for PDM.
89

Performance Analysis of CO2 Heat Pumps in Different Applications

Thanggavelu, Jaykumar January 2022 (has links)
This study focuses on researching the performance of CO2 heat pumps in different real-time applications and in some studies, it compares the performance to synthetic and other natural refrigerants based on heat pump data provided from buildings. The research on the performance of the CO2 heat pump is performed based on Sweden's climatic conditions. The study consists of four different case studies each focusing on the CO2 heat pump used for four different buildings. The first study evaluates the performance of air source CO2 heat pump installed in a residential building and performs cost benefit in comparison to district heating energy consumption. The second study investigates the performance of the air source CO2 heat pump for the district heating application and compares the same with other refrigerant heat pumps. The refrigerants compared with include Ammonia (R-717), Propane (R-290), R-134a (1,1,1,2-tetrafluoroethane). The third study examines the performance of air source CO2 heat pumps in a commercial building with the field measured data obtained directly from the heat pump sensors through the online portal “itop”. The fourth study analyses the performance of a CO2 heat pump with that of a propane (R-290) heat pump for a commercial swimming pool application.  The study is performed using a simulation model created using Microsoft Excel Sheets and Cool Prop add-in, a thermophysical property database. The simulation model makes use of formulae of heat pumps to analyse the performance of the heat pump systems. The climatic data for Stockholm is taken from ASHRAE IWEC 2 database. The results of the study show advantages of CO2 heat pumps when used for combined purposes like space heating, space cooling and domestic hot water over the heat pumps using other refrigerants for their operation, as these refrigerants when operated at high condensation temperature led to low Coefficient of Performance (COP). The first study on residential building CO2 heat pumps showed a cost savings of about 116,000 kr per year even in high-pressure operations concerning the annual cost of district heating, which is about 30% of the total cost district heating with auxiliary equipment. The study also examined the energy saving over the usage of an ejector used in the heat pump which reached an average energy saving of 8%. The second study shows the dominance of the performance of CO2 over other refrigerants for district heating purposes. The third study indicates the performance of the CO2 heat pump in the application using real-time measure data. The fourth study illustrates an increase in overall COP of about 10% from the CO2 heat pump in comparison to that of propane refrigerant for swimming pool application. These results show that when the domestic hot water demand is higher, the CO2 heat pump performs better than other refrigerants specifically because the COP of other refrigerants is lower at high condensation temperatures. / Denna studie fokuserar på att undersöka prestandan hos CO2-värmepumpar i olika realtidsapplikationer och i vissa studier jämför den prestandan med syntetiska och andra naturliga köldmedier baserat på värmepumpsdata från byggnader. Forskningen kring CO2-värmepumpens prestanda utförs utifrån Sveriges klimatförhållanden. Studien består av fyra olika fallstudier som var och en fokuserar på CO2-värmepumpen som används för fyra olika byggnader. Den första studien utvärderar prestandan hos luftkällans CO2-värmepump installerad i ett bostadshus och ger kostnadsfördelar jämfört med energiförbrukningen för fjärrvärme. Den andra studien undersöker prestandan hos luftkällans CO2-värmepump för fjärrvärmeapplikationen och jämför densamma med andra köldmedievärmepumpar. Köldmedierna jämfört med inkluderar ammoniak (R-717), propan (R-290), R-134a (1,1,1,2-tetrafluoretan). Den tredje studien undersöker prestandan hos luftkällans CO2-värmepumpar i en kommersiell byggnad med fältuppmätta data som erhålls direkt från värmepumpens sensorer via onlineportalen "itop". Den fjärde studien analyserar prestandan hos en CO2-värmepump med den hos en propan (R-290) värmepump för en kommersiell simbassängapplikation. Studien utförs med hjälp av en simuleringsmodell skapad med Microsoft Excel Sheets och Cool Prop-tillägget, en termofysisk egenskapsdatabas. Simuleringsmodellen använder formler för värmepumpar för att analysera värmepumpsystemens prestanda. Klimatdata för Stockholm är hämtade från databasen ASHRAE IWEC 2.  Resultaten av studien visar fördelarna med CO2-värmepumpar när de används för kombinerade ändamål som rumsuppvärmning, rumskylning och tappvarmvatten jämfört med värmepumpar som använder andra köldmedier för sin drift, eftersom dessa köldmedier när de används vid hög kondensationstemperatur ledde till låg koefficient prestanda (COP). Den första studien om bostadshus CO2-värmepumpar visade en kostnadsbesparing på cirka 116 000 kr per år även i högtrycksdrift avseende den årliga kostnaden för fjärrvärme, vilket är cirka 30 % av den totala kostnaden för fjärrvärme med hjälputrustning. Studien undersökte också energibesparingen jämfört med användningen av en ejektor som används i värmepumpen som nådde en genomsnittlig energibesparing på 8 %. Den andra studien visar dominansen av CO2s prestanda över andra köldmedier för fjärrvärmeändamål. Den tredje studien indikerar CO2-värmepumpens prestanda i applikationen med hjälp av mätdata i realtid. Den fjärde studien illustrerar en ökning av den totala COP på cirka 10 % från CO2-värmepumpen jämfört med den för propan-köldmedium för simbassängapplikationer. Dessa resultat visar att när efterfrågan på tappvarmvatten är högre presterar CO2-värmepumpen bättre än andra köldmedier, särskilt eftersom COP för andra köldmedier är lägre vid höga kondensationstemperaturer.
90

Les composés phénoliques des raisins : étude du potentiel qualitatif et des procédés émergeants d'extraction / The phenolic compounds of grapes : study of qualitative potential and emerging processes of extraction

El Darra, Nada 21 January 2013 (has links)
Ce travail porte sur l’amélioration de l’extraction des composés phénoliques à partir des raisins tout au long de la chaîne de la vinification en rouge. La qualité des vins rouges est en grande partie déterminée par les composés phénoliques. Parmi les composés phénoliques, les anthocyanes, qui sont responsables de la couleur, et les tanins, à l’origine de la sensation d’astringence. Pour augmenter la quantité des composés phénoliques présents dans le vin, un développement des procédés permettant d’améliorer la diffusion des composés phénoliques durant la vinification en rouge doit être mis en jeu. Nous avons entamé notre étude par un suivi de la maturité phénolique des raisins rouges appartenant à différentes parcelles de la société château KSARA localisées dans la vallée de la Békaa tout en se servant des méthodes Glories (1&2) et ITV. Quant à l’amélioration de l’extractibilité des composés phénoliques durant la vinification en rouge, différents prétraitements ont été appliqués dans le but d’améliorer la diffusion de ces composés. Parmi ces procédés, les technologies suivantes ont été abordées dans notre étude: les électrotechnologies (CEP), les ultrasons, le chauffage modéré, le traitement enzymatique, la macération préfermentaire à froid et la thermovinification. Ces techniques permettent d’endommager ou de fragiliser les membranes et/ou parois cellulaires facilitant ainsi la libération du contenu cellulaire vers le milieu extérieur. Les cinétiques d’extraction des composés phénoliques ont pu être modélisées par le modèle empirique de Peleg et le modèle cinétique simplifié afin d’estimer les rendements d’extraction. De plus, dans ce travail, l’accent a été mis sur les propriétés antiradicalaires et antimicrobiennes des composés phénoliques extraits de différentes variétés de raisins fournis par la société Château KSARA. Pour valoriser les co-produits de la vinification, le chauffage ohmique pulsé (COP) a été appliqué sur le marc du raisin dans le but d’améliorer l’extraction de ses composés phénoliques. L'optimisation du choix de la date des vendanges et l'amélioration des procédés d’extractions des composés phénoliques durant la vinification en rouge, pourraient nous conduire à élaborer un vin d'une meilleure qualité. Ce travail étant effectué, il sera intéressant comme projet à venir de valider ces différents pré-traitements à grande échelle pour une perspective d’application industrielle. / This study focuses on improving the extraction of phenolic compounds from grapes throughout the chain of red winemaking. The quality of wine is mainly determined by the phenolic compounds. From these phenolic compounds, the anthocyanins, which are responsible of the color and tannins, the responsible of the astringency. In order to increase the amount of phenolic compounds present in wine, a development of methods used to improve the extraction of phenolic compounds during the red vinification should be discussed. We began our study by using two methods Glories (1&2) and ITV to monitor the phenolic maturity of red grapes grown in the vineyards in the province of Bekaa-Château KSARA S.A.L. Whereas for the improvement of the extractibility of phenolic compounds during the vinification, different pre-treatments were applied in order to ameliorate the diffusion of these compounds. Among these process, the following technologies were discussed in our study: the electrotechnologies (PEF), the ultrasound, the moderate heat treatment, the enzymatic treatment, the cold maceration and the thermovinification. These techniques are able to weaken the cell walls and facilitate the diffusion of grape’s phenolic compounds during vinification. Peleg’s equation and the simplified kinetic model were shown to be suitable for describing the extraction kinetics for phenolic compounds and for the estimation of the extraction yield of polyphenols. Furthermore, in this study, the antiradical and antimicrobial activities of phenolic compounds extracted from grapevine varieties of Château KSARA-Bekaa-Lebanon were analyzed. To valorize the by-products of the vinification, the pulsed ohmic heating (POH) was applied on the grape pomace in order to ameliorate the extraction of the phenolic compounds. The optimization of the choice of the harvesting date and the amelioration of the extraction of phenolic compounds during the red vinification, will conduce to elaborate a high quality of wine. After this study, it will be interesting to validate the different pre-treatments at large scale for a perspective of an industrial application.

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