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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.
31

門市經營績效與管理-以個案A公司為例 / A case study of operation performance and management on chain stores

洪穎菁, Hung, Ying Ching Unknown Date (has links)
台灣連鎖零售業發展至今,市場已漸趨成熟,業者亦逐漸累積成功的商業經營模式。然而,連鎖通路勝出的關鍵因子不僅是規模經濟與經營效率,更需要了解每一門市經營效益,具備洞悉當地市場的能力,可以即時發現問題與調整經營方式。例如,如何透過經營活動產生的數值,分析店舖的績效(Ittner and Lacker 1998);瞭解不同類型門市經營模式的關鍵的經營因素,以及可以提供門市經營變化預警訊息之預警指標,門市經營(李孟熹1994),為連鎖式經營業者應予重視之管理議題,亦為值得深入探討之研究議題。 本研究以國內某3C連鎖零售通路為研究樣本,以其2009年1月至2012年5月的營運數據為資料,實證分析影響該業者門市經營績效的因素。並就商品銷售變化面、營業面積運用效益面與門市獲利面,作進一步之分析。 透過實證模型結果分析,在「商品銷售變化面」,來客數與商品別週邊耗材營業額呈顯著正向關係。週邊耗材商品業績良好與否的變化與門市來客數之增減有密切關係,可做為評估門市經營客群的掌握度。另外,商圈類型為社區型、都市型與鄉鎮型門市商品銷售以2C為主,說明不同商圈類型的門市確實有不同商品組合,門市商品配置時需作調整以利滿足當地顧客購買需求。 在「營業面積運用效益面」,每人負責的坪數與坪效呈顯著負向關係。當每人負責的坪數越大時,該門市的坪效越差,也代表每人業績貢獻度越低,當店業績越少,營業坪數的承租應考量人員守備範圍以利最佳化。 在「門市獲利面」,單一門市經營時,來客數的掌握與特定商圈類型(社區型、都市型與鄉鎮型)門市的週邊配件業績占比可為衡量經營優劣的指標;多家門市共同經商圈時,業績因新設點的加入而擴大,的確透過多家門市可達到較高的商圈覆蓋範圍,在市場上掠奪競爭者的業績;但該商圈的整體獲利鮮少有提升,因需負擔相同的營業費用項目(如租金、人事費用、管理費用),且經營時程拉長,同商圈內的門市相互競爭狀況無法改善,出現將市場越做越小的情形。 / The developments of chain stores market in retailer industry mature gradually right now. Enterprises have accumulated commercial model how to operate successfully as well. However, the key point of success is not only scale economy and operating efficiency, but also operating benefit of per store. Having the ability of insight local market can discover problem and remodel it. For example, we can analyze stores performance by the operation information.(Ittner and Lacker 1998)we can understand the key operation factor in different kind of store. At the same time, that can be a warning sign for observing changing. Stores management is a important issue that enterprise should attach importance to it and it is valuable to investigate deeply. This thesis is based on 3C retailer industry, and the data period is from January, 2009 to May, 2012. Practical demonstration analyzes which kind factors will influence stores performance, and seperately discuss different aspect, sale change of product, average sale of per unit area, and profit &loss to do advanced analysis. According to the result of practical model, in the aspect of changing of product sales, consumer flow is positive related with accessory sales. The increase of the accessory sales will raise consumer flow. On the other hand, marketplace types are community type, city type, and countryside type which sale more consumer product than other marketplace type. So, different market type has different product portfolio, and need to adjust to fit the demand of local customer. In the aspect of average sales per unit area, average space per person is negative related with average sales per unit area. If area space per person is larger, average sales per unit area is less. It also means an average sale per person is lower. If the store sales decrease, we should consider optimizing average space per person. In the aspect of profit & loss on chain stores, accessory ratio can be an indicator whether the operation is excellent on particular marketplace type and consumer flow. When several stores cooperate to manage one marketplace, the sale will increase due to new store adding, and expand the market share. However, the total profit is rarely increasing due to expending double overheads (rental, salary, administration fee, etc.). These stores in same marketplace compete with each other in the long term. If this situation can’t improve, the market share will become more and more less.
32

Etude de la croisssance CVD des films minces de 3C-SiC et élaboration du cantilever AFM en 3C-SiC avec pointe Si intégrée / Study of the CVD growth of 3C-SiC thin films and fabrication of 3C-SiC based AFM centilever with integrated Si type

Jiao, Sai 12 November 2012 (has links)
Parmi les polytypes les plus connus du carbure de silicium (SiC), le polytype cubique (3C-SiC), est le seul qui peut croitre sur des substrats silicium. L’hétérostructure 3C-SiC/Si est intéressante non seulement pour son faible coût de production mais aussi pour la conception de Systèmes Micro-Electro-Mécaniques (« MEMS »). La valeur élevée du module de Young du 3C-SiC, comparé à celui du silicium, permettrait à des cantilevers submicroniques, fabriqués à partir de films minces de 3C-SiC, de vibrer à ultra-hautes fréquences (>100MHz). Cette haute fréquence de résonance est la clé pour obtenir un système AFM non-contact ultra-sensible et rapide. Cependant, il n’existe pas de cantilever en SiC disponible sur le marché en raison de la difficulté à élaborer des films minces de 3C-SiC de bonne qualité, la technique de synthèse la plus utilisée étant le Dépôt Chimique en phase Vapeur (CVD). La raison première de cette difficulté à obtenir un matériau de bonne qualité réside essentiellement dans l’important désaccord de maille et la différence de dilatation thermique entre le 3C-SiC et Si qui génèrent des défauts cristallins à l’interface et jusqu’à la surface du film de 3C-SiC, la zone la plus défectueuse se localisant auprès de l’interface……. / Among aIl the well known polytypes ofihe silicon carbide (SiC), the cubic polytype (3C-SiC) is the only one that min be grown on silicon substrates. This heterostructure 3C SiC/Si ta interesting not only for its low production cost but also for the design of tise Micro-Electro-Mechanical Systems (MEMS). The high value ofthe Young’s modulis the 3C-SiC, compared to the silicon, allows submicronic cantilevers, fabrmcated from tIse 3C-SiC thin filins, to resonate at ultra-high frequency (>100MHz). The high resonant frequency is the key to obtain s fast, ultra-sensitive non-contact AFM systein.However, there isn’t any SiC cantilevers available on the market because of the difficulty to elaborate gond quality 3C-SiC thin films, with tIse Chemical Vapor Deposition (CVD) technique being tIse most frequently used synthesis technology. Tise first reason of tIse difficulty with the CVD technology to obtain gond quality thin film rests essentially in the important lattice mismatch and the difference in thermal expansion coefficient existing between 3C SiC and Si which generate crystalline defects at the interface and propagating tilI the 3C-SiC filin surface, with the inost defective zone localizing near the interface…….
33

Addition of Ge to the H-Si-C chemical system during SiC epitaxy / Addition de Ge dans le système chimique H-Si-C durant l'épitaxie de SiC

Alassaad, Kassem 03 November 2014 (has links)
Ce travail concerne l'ajout de GeH4 au système de précurseurs gazeux classique SiH4+C3H8 pour la croissance épitaxiale de SiC par dépôt chimique en phase vapeur. L'objectif principal était d'explorer l'influence de la présence de l'élément Ge (impureté isoélectronique à SiC), dans la matrice SiC ou à sa surface, sur les mécanismes de croissance et sur la qualité et les propriétés des couches minces déposées. La croissance épitaxiale a été réalisée dans la gamme de température 1450-1600°C sur des substrats 4H-SiC(0001) désorientés fortement (4° et 8°) ou faiblement (0° et 1°). Sur les germes désorientés, nous avons exploré l'impact des atomes de Ge sur la qualité des couches homoépitaxiales, d'un point de vue morphologique et structural. Les mécanismes d'incorporation de cette impureté ont été étudiés en fonctions des paramètres de croissance. Il a été montré que l'incorporation de cet élément peut être contrôlée dans la gamme 1x1016 - 7x1018 at.cm-3. De plus, cette incorporation de Ge s'accompagne d'une augmentation du dopage de type n. Les caractérisations électriques de ces couches montrent une amélioration de la mobilité et de la conductivité électrique du matériau 4H-SiC sans aucun impact négatif sur les caractéristiques de contact Schottky. Sur les substrats faiblement désorientés, GeH4 a été ajouté à la phase gazeuse uniquement pendant l'étape de préparation de la surface, c’est-à-dire avant d'initier la croissance de SiC. Il a été montré que des couches hétéroépitaxiales de 3C-SiC exemptes de macles peuvent être déposées dans une fenêtre de conditions expérimentales (température et flux de GeH4). Un mécanisme permettant l'élimination des macles a été proposé. Il implique une étape transitoire de croissance homoépitaxiale, favorisée par la présence de Ge liquide à la surface, suivie de la nucléation de 3C-SiC sur les larges terrasses résultant du facettage des marches. Ces couches de 3C-SiC ont été caractérisées électriquement par microscopie à force atomique en mode conduction / In this work, addition of GeH4 gas to the classical SiH4+C3H8 precursor system is reported for the epitaxial growth of SiC by chemical vapor deposition. The main objective of this fundamental study is to explore the influence of Ge presence within SiC lattice or at its surface on the overall growth mechanism and the grown layer quality and properties. Epitaxial growth was performed either on high off axis (8 and 4°) or low off-axis (1° and on-axis) 4H-SiC substrate in the temperature range 1450-1600°C. On high off-axis seeds, we discussed the impact of Ge atoms on the homoepitaxial layer quality from surface morphological and structural point of view. Ge incorporation mechanism in these layers as a function of growth parameters was also investigated. The Ge incorporation can be controlled from 1x1016 - 7x1018 at.cm-3. Moreover, a clear link between n-type doping and Ge incorporation was found. Electrical characterizations of these layers show an improvement of electron mobility and conductivity of 4H-SiC material while the performances of Schottky contacts were not negatively impacted. On low off-axis seeds, GeH4 was added to the gas phase only during the surface preparation step, i.e. before starting the SiC growth. It was found that there is a conditions window (temperature and GeH4 flux) for which heteroepitaxial 3C-SiC twin free layers can be grown. Interpretation of the results allowed proposing a mechanism leading to twin boundary elimination. It involves a transient homoepitaxial growth step, favored by the presence of liquid Ge at the surface, followed by 3C nucleation when large terraces are formed by step faceting. Electrical characteristics of the twin free 3C-SiC layers were studied using conductive atomic force microscopy (c-AFM)
34

[en] COORDINATION SUPPORT IN COLLABORATIVE SYSTEMS: ACTION RESEARCH WITH LEARNERS AND MEDIATORS ACTING IN DISCUSSION FORUMS IN A DISTANCE COURSE / [pt] SUPORTE À COORDENAÇÃO EM SISTEMAS COLABORATIVOS: UMA PESQUISA-AÇÃO COM APRENDIZES E MEDIADORES ATUANDO EM FÓRUNS DE DISCUSSÃO DE UM CURSO A DISTÂNCIA

DENISE DEL RE FILIPPO 10 June 2008 (has links)
[pt] Nesta tese são investigadas ferramentas de suporte à coordenação de fóruns de discussão de cursos a distância. A pesquisa é fundamentada na aprendizagem colaborativa e do Modelo 3C de Colaboração e utiliza a pesquisaação como método de pesquisa. Num fórum realizado como uma atividade colaborativa, a aprendizagem ocorre principalmente através das trocas de mensagens entre os aprendizes, o que demanda coordenação. A coordenação nesta tese é entendida como um das 3 dimensões da colaboração evidenciadas no Modelo 3C: comunicação, coordenação e cooperação. Os resultados desta tese, que incluem dados, análises, procedimentos, reflexões e implementação dos serviços e funcionalidades investigados, foram obtidos após 3 anos de uma pesquisa- ação. Na pesquisa-ação, o pesquisador conduz a pesquisa realizando ações sucessivas que busquem reduzir um problema específico em um ambiente real. Nesta tese, o ambiente real é o curso Tecnologias de Informação Aplicadas à Educação da PUC-Rio e o problema identificado é a dificuldade de coordenação dos fóruns do curso. A ação é a disponibilização de ferramentas de suporte à coordenação no AulaNet, o ambiente de ensino e aprendizagem para web utilizado no curso. A característica comum das ferramentas investigadas é a de disponibilizar informações sobre o andamento do fórum sem que seja necessário fazer uso da interface web para desktop do AulaNet: para isto, grafos, gráficos, dados estatísticos e notificações são apresentados através de PDAs, celulares e janelas pop-up no desktop. A avaliação das ferramentas desenvolvidas é feita a cada semestre: avaliando-se como aprendizes e mediadores usam as ferramentas, melhorias ou novas ferramentas são propostas e investigadas no semestre seguinte, num processo cíclico. / [en] In this thesis tools for the coordination support of discussion forums in a distance course are investigated. The research is conducted from the point of view of collaborative learning and the 3C Collaboration Model and uses action research as a method. In a forum carried out as a collaborative activity, learning takes place mainly through the exchange of messages among learners, which demands coordination. Coordination in this thesis is understood as one of the 3 dimensions of collaboration as made evident in the 3C Model: communication, coordination and cooperation. The results of this thesis, which include data, analyzes, procedures, reflections and implementation of the services and functionalities investigated, were obtained in the course of 3 years of action research. In action research the researcher performs successive actions aiming at minimizing a specific problem in a real environment. In this thesis, the real environment is the Information Technologies Applied to Education course at PUC-Rio and the problem identified is a difficulty in the coordination of the course`s forums. The action is the offering of support tools for coordination in the AulaNet, the web-based education and learning environment used in the course. The common characteristic of the tools investigated is the offering of information on the progress of the forum without the need to use the AulaNet`s desktop web interface: with this objective, graphs, statistical data and notifications are presented through PDAs, cell- phone SMSs and pop-up windows in the desktop. An assessment of the tools developed is carried out every semester: through the evaluation of the use of the tools by learners and mediators, improvements or new tools are proposed for the following semester, in a cyclical process.
35

Cross Cultural Competence : Ett sätt att förstå vår värld / Cross Cultural Competence : A way to understand our world

Lennerman, Carl January 2010 (has links)
<p>Vi strävar alltid efter att förstå det som sker i den värld vi lever i. Till vår hjälp har vi olika referenser och kunskaper som vi har lärt oss under våra liv. Dessa referenser och kunskaper förenklar och förklarar våra upplevelser och sätter in dem i ett sammanhang. Utan detta sammanhang blir enskilda händelser omöjliga att förstå och vi tvingas navigera oss fram med förbundna ögon. Kultur är ett av de verktyg vi människor använder för att förklara den verklighet vi lever i. Vi omges ständigt av en mängd olika kulturella kontexter med sina egna koder och sammanhang. För att kunna interagera med dessa kulturer måste vi ha en förståelse för vad kultur är och hur det påverkar våra handlingar och tankar. För en soldat eller officer som skall operera i en internationell miljö blir denna kunskap ännu viktigare, då det kulturella avståndet mellan människor tenderar att växa exponentiellt i förhållande till det geografiska avståndet. Detta är en av de viktigaste erfarenheter som man dragit under 2000-talets internationella konflikter. Till följd av detta så har institutioner över hela världen startat projekt i syfte att utveckla utbildningar och träningsprogram som skall öka förmågan att hantera kultur och kulturell problematik vid militära insatser. Denna uppsats huvudsyfte är att med hjälp av Brian A. Selmeskis 3C koncept undersöka hur den svenska Försvarsmakten och Försvarshögskolan hanterar kultur och kulturell problematik i sin utbildning. Målet med uppsatsen är att identifiera områden som kan utvecklas i syfte att utveckla Cross Cultural Competence.</p> / <p>We always try to make sense of the things that happens in the world we live in. To our help we have different references and knowledge that we have learned during our life. These references and knowledge simplifies and explains our experiences and put them in to context. Without this context single events becomes impossible to understand and we are forced to navigate with our eyes bound. Culture is one of the tools, we humans use to explain the reality we live in. We are constantly surrounded by a wide range of different cultural contexts with there own codes and conducts. To be able to interact with these cultures we must have a understanding for what culture is and how it affect our actions. For soldier or an officer that will operate in an international environment, this knowledge becomes even more important cause the cultural distance between people tend to grow exponentially in relations to the geographical distance. This is one of the most important experiences from the 21 st century’s international conflicts. As a result of this, institutions all over the world have started projects with the purpose to develop educations and training programs that will increase the ability to manage culture and cultural problems. This essays main purpose it to with the help of Brian A. Selmeskis 3C concept study how the Swedish Defence and the Swedish National Defence Collage handles culture and cultural problems in their education. The goal with the essay is to identify areas that can be developed with the purpose to evolve Cross Cultural Competence.<strong><em></em></strong></p>
36

Cross Cultural Competence : Ett sätt att förstå vår värld / Cross Cultural Competence : A way to understand our world

Lennerman, Carl January 2010 (has links)
Vi strävar alltid efter att förstå det som sker i den värld vi lever i. Till vår hjälp har vi olika referenser och kunskaper som vi har lärt oss under våra liv. Dessa referenser och kunskaper förenklar och förklarar våra upplevelser och sätter in dem i ett sammanhang. Utan detta sammanhang blir enskilda händelser omöjliga att förstå och vi tvingas navigera oss fram med förbundna ögon. Kultur är ett av de verktyg vi människor använder för att förklara den verklighet vi lever i. Vi omges ständigt av en mängd olika kulturella kontexter med sina egna koder och sammanhang. För att kunna interagera med dessa kulturer måste vi ha en förståelse för vad kultur är och hur det påverkar våra handlingar och tankar. För en soldat eller officer som skall operera i en internationell miljö blir denna kunskap ännu viktigare, då det kulturella avståndet mellan människor tenderar att växa exponentiellt i förhållande till det geografiska avståndet. Detta är en av de viktigaste erfarenheter som man dragit under 2000-talets internationella konflikter. Till följd av detta så har institutioner över hela världen startat projekt i syfte att utveckla utbildningar och träningsprogram som skall öka förmågan att hantera kultur och kulturell problematik vid militära insatser. Denna uppsats huvudsyfte är att med hjälp av Brian A. Selmeskis 3C koncept undersöka hur den svenska Försvarsmakten och Försvarshögskolan hanterar kultur och kulturell problematik i sin utbildning. Målet med uppsatsen är att identifiera områden som kan utvecklas i syfte att utveckla Cross Cultural Competence. / We always try to make sense of the things that happens in the world we live in. To our help we have different references and knowledge that we have learned during our life. These references and knowledge simplifies and explains our experiences and put them in to context. Without this context single events becomes impossible to understand and we are forced to navigate with our eyes bound. Culture is one of the tools, we humans use to explain the reality we live in. We are constantly surrounded by a wide range of different cultural contexts with there own codes and conducts. To be able to interact with these cultures we must have a understanding for what culture is and how it affect our actions. For soldier or an officer that will operate in an international environment, this knowledge becomes even more important cause the cultural distance between people tend to grow exponentially in relations to the geographical distance. This is one of the most important experiences from the 21 st century’s international conflicts. As a result of this, institutions all over the world have started projects with the purpose to develop educations and training programs that will increase the ability to manage culture and cultural problems. This essays main purpose it to with the help of Brian A. Selmeskis 3C concept study how the Swedish Defence and the Swedish National Defence Collage handles culture and cultural problems in their education. The goal with the essay is to identify areas that can be developed with the purpose to evolve Cross Cultural Competence.
37

從3C產品產銷看防盜展示座之產業發展 / A Study of Anti-theft display holder via Consumer Electronics Products on Industry Development

林郭田 Unknown Date (has links)
一般而言,防盜展示座是用於3C賣場、展覽會場、實體體驗店鋪、影音視聽設備販售商場、通訊賣場或店面等場所,而被使用的商品更包含手機、影音視聽設備、照相機、攝影機、平板電腦、筆記型電腦、通訊設備等3C商品,當展覽會場或銷售商場將3C產品安裝於展示座之上,即可安全的提供商品陳列,而這樣提供一個安全性的商品銷售的產品,便是防盜展示座與3C產品間密不可分的說明。換言之,當3C產品的銷售量或生產量達到一定程度時,防盜展示座的需求量也會隨之上升。因此,本研究擬欲透過3C產品的生產與銷售概況,據以進一步瞭解防盜展示座的產業發展,故本研究擬針對3C產品之營運現況及產銷現況進行探究,其研究結果顯示: 1. 防盜展示座的產業預期具有正向的發展; 2. 3C產品之產銷現況受季節因素的影響; 3. 3C產品之營運現況是呈現成長趨勢; 4. 防盜展示座預期可能會受季節因素影響。
38

Optical and electrical properties of highly excited 3C-SiC crystals and heterostructures / Stipriai sužadintų 3C-SiC kristalų ir heterostruktūrų optinės ir elektrinės savybės

Manolis, Georgios 27 March 2013 (has links)
This thesis is dedicated to investigation of carrier dynamics in 3C-SiC crystals and heterostructures by using light-induced transient gratings and differential transmission techniques. The experimental studies in a wide range of excess carrier densities and temperatures revealed the influence of several particular growth conditions in different growth techniques on electronic properties of grown layers, and hence, a possibility to characterize indirectly the structural perfection of a layer by non-destructive optical means. Based on these results, we were able to evaluate and compare quality of 3C-SiC specimens manufactured by nearly all currently available growth techniques and to distinguish the most promising growth methods for 3C-SiC semiconductor. Moreover, we found a novel way, based on DT technique, to determine the carrier trap concentration in finite thickness layers, as well as to attribute them to specific impurity species. Finally, we investigated the influence of substrate surface features on carrier lifetime and mobility of the overgrown layers. / Disertacija yra skirta krūvininkų dinamikos tyrimams 3C-SiC kristaluose ir heterostruktūrose naudojant šviesa indukuotų dinaminių gardelių ir diferencinio pralaidumo metodikas. Atlikti tyrimai plačiame žadinimų ir temperatūros intervale atskleidė skirtingų auginimo technologijų ir jų tam tikrų parametrų įtaką opto-elektroninėms užaugintų sluoksnių savybėms, kas įgalino atlikti medžiagos neardančią, optinę kristalų struktūrinės kokybės charakterizaciją. Remiantis gautais rezultatais mes galėjome palyginti visomis plačiausiai naudojamomis auginimo technologijomis užaugintų 3C-SiC bandinių kokybę, taigi ir įvertinti perspektyviausią 3C-SiC puslaidininkio auginimo metodą. Šiame darbe atradome naują būdą, paremtą diferencinio pralaidumo metodika, krūvininkų gaudyklių koncentracijos ir šių priemaišinių atomų prigimties nustatymui pakankamai plonuose sluoksniuose. Taip pat, tyrėme padėklo paviršiaus įtaką krūvininkų gyvavimo laikui ir judriui epitaksiniuose sluoksniuose.
39

Stipriai sužadintų 3C-SiC kristalų ir heterostruktūrų optinės ir elektrinės savybės / Optical and electrical properties of highly excited3C-SiC crystals and heterostructures

Manolis, Georgios 27 March 2013 (has links)
Disertacija yra skirta krūvininkų dinamikos tyrimams 3C-SiC kristaluose ir heterostruktūrose naudojant šviesa indukuotų dinaminių gardelių ir diferencinio pralaidumo metodikas. Atlikti tyrimai plačiame žadinimų ir temperatūros intervale atskleidė skirtingų auginimo technologijų ir jų tam tikrų parametrų įtaką opto-elektroninėms užaugintų sluoksnių savybėms, kas įgalino atlikti medžiagos neardančią, optinę kristalų struktūrinės kokybės charakterizaciją. Remiantis gautais rezultatais mes galėjome palyginti visomis plačiausiai naudojamomis auginimo technologijomis užaugintų 3C-SiC bandinių kokybę, taigi ir įvertinti perspektyviausią 3C-SiC puslaidininkio auginimo metodą. Šiame darbe atradome naują būdą, paremtą diferencinio pralaidumo metodika,krūvininkų gaudyklių koncentracijos ir šių priemaišinių atomų prigimties nustatymui pakankamai plonuose sluoksniuose. Taip pat, tyrėme padėklo paviršiaus įtaką krūvininkų gyvavimo laikui ir judriui epitaksiniuose sluoksniuose. / This thesis is dedicated to investigation of carrier dynamics in 3C-SiC crystals and heterostructures by using light-nduced transient gratings and differential transmission techniques. The experimental studies in a wide range of excess carrier densities and temperatures revealed the influence of several particular growth conditions in different growth techniques onelectronic properties of grown layers, and hence, a possibility to characterize indirectly the structural perfection of a layer by non-destructive optical means. Based on these results, we were able to evaluate and compare quality of 3C-SiC specimens manufactured by nearly all currently available growth techniques and to distinguish the most promising growth methods for 3C-SiC semiconductor. Moreover, we found a novel way, based on DT technique, to determine the carrier trap concentration in finite thickness layers, as well as to attribute them to specific impurity species. Finally, we investigated the influence of substratesurface features on carrier lifetime and mobility of the overgrown layers.
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[en] COMPONENT-BASED GROUPWARE DEVELOPMENT BASED ON THE 3C COLLABORATION MODEL / [pt] DESENVOLVIMENTO DE GROUPWARE COMPONENTIZADO COM BASE NO MODELO 3C DE COLABORAÇÃO

MARCO AURELIO GEROSA 12 July 2006 (has links)
[pt] Groupware é evolutivo e é difícil de construir e de manter, e acaba tendo um código desorganizado e difícil de evoluir. Nesta tese é proposta uma abordagem de desenvolvimento de groupware baseado em componentes concebidos em função do modelo 3C de colaboração. No modelo 3C, a colaboração é analisada a partir da comunicação, coordenação e cooperação. Na abordagem proposta, partese das necessidades de colaboração do grupo, analisadas com base no modelo, e componentes de software também organizados em função do modelo são utilizados para compor a solução. Como estudo de caso, a abordagem é aplicada no desenvolvimento da nova versão do ambiente AulaNet, cujo código padece dos problemas mencionados anteriormente. Neste estudo de caso, são desenvolvidos component kits para instanciar os serviços de comunicação do ambiente. Os componentes possibilitam compor, recompor e customizar os serviços de modo a refletir alterações na dinâmica de colaboração. / [en] Groupware is evolutionary and difficult to develop and maintain. Thus, its code becomes unstructured and difficult to evolve. In this thesis, a groupware development approach based on components organized according to the 3C collaboration model is proposed. In this model, collaboration is analyzed based on communication, coordination and cooperation. Collaboration necessities of the group, analyzed based on the 3C model, are mapped to software components, also organized according to the model, in order to compose the system. The proposed approach is applied as a case study to the development of the new version of the AulaNet environment. The environment´s code currently suffers the mentioned problems. In order to instantiate the communication services of the environment, for the case study, 3C based component kits were developed. The components allow the composition, re-composition and customization of the services in order to reflect collaboration dynamics changes.

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