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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.
51

Avaliação da deposição da calda de pulverização em função do tipo de ponta e do volume aplicado, na cultura do feijão / Evaluation of the deposition of syrup of spraying depending on the type of edge and the amount applied, in the culture of beans

Limberger, Aline Regina 29 September 2006 (has links)
Made available in DSpace on 2017-07-10T17:37:04Z (GMT). No. of bitstreams: 1 Aline Regina Limberger.pdf: 204926 bytes, checksum: b8fbd6dc1e3385987c7eefab743c20cd (MD5) Previous issue date: 2006-09-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The culture of the beans (Phaseolus vulgaris L.) is one of most important in Brazilian agriculture. The occurrence of illnesses is a serious factor of influence in its development and productivity. One of the critical points of the current system of production of agricultural cultures is the use of defensive defensive, besides raising the production cost, can cause direct and indirect ambient contaminations. The choice and the adequate use of spraying beaks are essential for the correct application of defensive. Due to those needs the present work was carried out in Cascavel PR, in the harvest 2004/2005, using the beans IAPAR 81, with the objective evaluating the amount of syrup deposited on the beans leaves, varied the volume of syrup applied and the beaks types used in the spraying bar, used tracer substance, simulating the physical characteristics of the solutions of the products. To evaluate the spraying distribution, fifteen leaves were collected per plant in different extracts (higher, medium and lower), with the purpose of evaluating the syrup penetration, in agreement with the different beaks and applied volumes. The experimental design was arranged in randomized complete blocks, in factorial arrangement, with four beaks and point of the type simple fan, double fan, double fan with air injection and empty cone and 3 syrup volumes (100, 200 and 300 L ha-1). In agreement with the results obtained and in the conditions that the present work was carried out.,concluded that: The syrup volume that presented larger depositions , in different extracts of the beans plants was of 300 L ha-1; for larger depositions in the higher extract of the beans plants, the best combination is to use beaks of Empty Cone, with volumes of the 300 L ha-1 and for larger depositions for the medium and lower extracts of the bean plants, the best combination is to use peaks Double Fan with air injection, volumes of 100, 200 or 300 L ha-1 / A cultura do feijão (Phaseolus vulgaris L.) é uma das mais importantes na agricultura brasileira. A ocorrência de doenças é um sério fator de influência no seu desenvolvimento e produtividade. Um dos pontos críticos do atual sistema de produção de culturas agrícolas é o uso de agrotóxicos, que, além de elevar o custo de produção, pode causar contaminações ambientais diretas e indiretas. A escolha e o uso adequado de bicos de pulverização são essenciais para a correta aplicação de agrotóxicos. Diante dessas necessidades foi conduzido o presente trabalho no município de Cascavel PR, na safra de 2004/2005, utilizando a variedade IAPAR 81, com o objetivo de avaliar a quantidade de calda depositada nas folhas do feijão, variando-se o volume de calda aplicada e os tipos de bicos utilizados na barra de pulverização, utilizando-se substância traçadora, simulando as características físicas das soluções de produtos fitossanitários. Para avaliar a distribuição da pulverização, foram coletadas quinze folhas por planta em diferentes extratos (superior, mediano e inferior), com a finalidade de avaliar a penetração da calda, de acordo com os diferentes bicos e volumes aplicados. O delineamento experimental constituiu-se de blocos ao acaso, em arranjo fatorial, compreendendo 4 bicos de pulverização com pontas do tipo leque simples, duplo leque, duplo leque com injeção de ar e cone vazio e 3 volumes de calda (100, 200 e 300 L ha-1 ). De acordo com os resultados obtidos e nas condições em que o presente trabalho foi conduzido, concluiu-se que: o volume de calda que apresentou maiores deposições, nos diferentes extratos das plantas de feijão foi o de 300 L ha-1; para maiores deposições no terço superior das plantas de feijão, a melhor combinação é utilizar bicos de Cone Vazio, com volumes de calda de 300 L ha-1 e para maiores deposições no terço mediano e inferior das plantas de feijão, a melhor combinação é utilizar bicos Duplo Leque com injeção de ar , com volumes de calda de 100 ,200 ou 300 L ha-1
52

CLIP-170 : Interaction avec LIS1, régulations et implication dans le fonctionnement du complexe dynéine/dynactine.

Coquelle, Frédéric 10 January 2003 (has links) (PDF)
La CLIP-170 (Cytoplasmic Linker Protein of 170 kDa) est requise, in vitro, pour l'établissement d'un lien statique entre les endosomes et les microtubules (MTs). Elle se localise, in vivo, aux bouts « plus » des MTs en croissance et semble participer ainsi à la capture de ces derniers au cortex cellulaire et aux kinétochores. Elle contribue au contrôle de la dynamique des MTs et semble aussi recruter le complexe moteur dynéine cytoplasmique/dynactine sur les extrémités « plus » des MTs, via son domaine carboxy-terminal. La CLIP-170 s'associe également aux kinétochores d'une façon dépendante du complexe dynéine/dynactine et de son domaine C-terminal. Ce domaine C-terminal contient deux motifs de type « doigt de zinc » (proximal et distal) probablement impliqués dans des interactions avec d'autres protéines.<br />Nous rapportons ici la démonstration d'une interaction directe entre la CLIP-170 et LIS1, une protéine capable, par ailleurs, d'interagir directement avec le complexe dynéine/dynactine. LIS1 est mutée chez de nombreux patients atteints d'une lissencéphalie de type I et semble jouer le rôle de co-facteur activateur de la dynéine cytoplasmique. Nous avons montré que cette interaction dépendait du doigt de zinc distal de la CLIP-170 et nous avons apporté des éléments indiquant une possible régulation de cette interaction par phosphorylation.<br />L'étude des fonctions cellulaires potentielles de cette interaction nous a permis de mettre en évidence un enrichissement de LIS1 aux extrémités « plus » des MTs. Elle a fourni des éléments substantiels laissant supposer que cette localisation, comme celle de la dynactine au même endroit, était dépendante du domaine C-terminal de la CLIP-170. Par ailleurs, nous avons démontré que la localisation de la CLIP-170 sur le kinétochore dépendait de son domaine d'interaction avec LIS1, et que le recrutement de LIS1 au même site dépendait du complexe dynéine/dynactine. L'ensemble de ces données suggère que LIS1 constitue un adaptateur entre la CLIP-170 et le complexe moteur dynéine/dynactine.<br />Parallèlement, nous avons initié l'étude de protéines LIS1 qui présentent chacune une mutation ponctuelle dans diverses régions conservées. Ces mutations ponctuelles ont été découvertes chez des patients atteints d'une lissencéphalie de type I plus ou moins sévère. Par des approches biochimiques, moléculaires et cellulaires, nous avons montré que, selon la sévérité de la maladie, les différentes propriétés de LIS1 (repliement, stabilité, localisations sub-cellulaires, interaction avec ses partenaires et liaison aux MTs) étaient plus ou moins affectées. À l'occasion de cette étude, nous avons également identifié les domaines de LIS1 impliqués dans l'interaction avec les MTs et d'autres partenaires comme les sous-unités catalytiques du PAFAH(I) (Platelet-Activating Factor Acétylhydrolase).
53

Hermes Technologies : En entreprenöriell process

Rahimi, Foad January 2005 (has links)
<p>Detta examensarbete beskriver problem och hinder som uppstår vid nyföretagande och entreprenörskap. Arbetet initierades i en period som karaktäriserades av stora nedskärningar inom den svenska högteknologi industrin och väldigt få examensarbeten var tillgängliga.</p><p>Den entreprenöriella processen och tankesättet har varit väldigt tongivande för det svenska samhället. Denna anda har producerat flera stora internationella storföretag. Även om inte alla entreprenörer når de internationella företag i storlek så har småföretagen en minst lika viktig roll för utvecklingen av samhället med det kreativa tankesättet och synen på affärsmöjligheter.</p><p>Rapporten består av litteraturstudie och en fallstudie Hermes Technologies. Med hjälp av modeller kring den entreprenöriella processen, teorier om de psykografiska förhållandena på högteknologiska marknader samt teorier kring skapandet av en markand och prissättning samt analysverktygen Affärsplattformen har en teoretisk bas byggts upp för att sedan appliceras på en fallstudie.</p><p>Teorin framhäver hur viktigt upptäckten av affärsmöjligheten är för framgång tillsammans med ett kreativt hanterande av resurserna.</p><p>Fallstudien består av uppstarten till grundandet av ett högteknologiskt utvecklingsföretag inom marknaden för Electronic Shelf Labeling system, ESL-system. Casestudien genomfördes vid ProNova Science Park i Norrköping som en del i pilotprojektet ”FörInkubatorn” vilket senare utvecklades till Drivbänken. Genom att tillämpa teorin på fallstudien framkom det att flera faktorer för att med framgång genomföra grundandet av Hermes Technologies saknades eller var bristfälliga.</p><p>Här framgår även hur grundandet av Hermes Technologies har genomförts. Vidare framförs hur detaljhandeln ställer sig inför införandet av ESL-system istället för dagens pappersmarkeringar.</p><p>Analysen klargjorde vilka faktorer som låg till grund för ett misslyckade samt vilka åtgärder som krävdes för att uppnå en mer tillfredsställande nivå. Erfarenhet var den ensamt största bristfälliga faktorn som resulterade i att projektet inte lyckades. För att kunna påverka denna faktor krävs det ofta flertaliga försök inom nyföretagande.</p><p>Resultatet påvisar att de teorier, som används i litteraturstudien, bör användas tillsammans med varandra för att uppnå bästa resultat vid nystartandet av ett företag. Detta kommer av att man på detta vis belyser problemet från flera infallsvinklar vilket ytterligare klargör de hinder som kan uppkomma eller har uppstått.</p>
54

Hermes Technologies : En entreprenöriell process

Rahimi, Foad January 2005 (has links)
Detta examensarbete beskriver problem och hinder som uppstår vid nyföretagande och entreprenörskap. Arbetet initierades i en period som karaktäriserades av stora nedskärningar inom den svenska högteknologi industrin och väldigt få examensarbeten var tillgängliga. Den entreprenöriella processen och tankesättet har varit väldigt tongivande för det svenska samhället. Denna anda har producerat flera stora internationella storföretag. Även om inte alla entreprenörer når de internationella företag i storlek så har småföretagen en minst lika viktig roll för utvecklingen av samhället med det kreativa tankesättet och synen på affärsmöjligheter. Rapporten består av litteraturstudie och en fallstudie Hermes Technologies. Med hjälp av modeller kring den entreprenöriella processen, teorier om de psykografiska förhållandena på högteknologiska marknader samt teorier kring skapandet av en markand och prissättning samt analysverktygen Affärsplattformen har en teoretisk bas byggts upp för att sedan appliceras på en fallstudie. Teorin framhäver hur viktigt upptäckten av affärsmöjligheten är för framgång tillsammans med ett kreativt hanterande av resurserna. Fallstudien består av uppstarten till grundandet av ett högteknologiskt utvecklingsföretag inom marknaden för Electronic Shelf Labeling system, ESL-system. Casestudien genomfördes vid ProNova Science Park i Norrköping som en del i pilotprojektet ”FörInkubatorn” vilket senare utvecklades till Drivbänken. Genom att tillämpa teorin på fallstudien framkom det att flera faktorer för att med framgång genomföra grundandet av Hermes Technologies saknades eller var bristfälliga. Här framgår även hur grundandet av Hermes Technologies har genomförts. Vidare framförs hur detaljhandeln ställer sig inför införandet av ESL-system istället för dagens pappersmarkeringar. Analysen klargjorde vilka faktorer som låg till grund för ett misslyckade samt vilka åtgärder som krävdes för att uppnå en mer tillfredsställande nivå. Erfarenhet var den ensamt största bristfälliga faktorn som resulterade i att projektet inte lyckades. För att kunna påverka denna faktor krävs det ofta flertaliga försök inom nyföretagande. Resultatet påvisar att de teorier, som används i litteraturstudien, bör användas tillsammans med varandra för att uppnå bästa resultat vid nystartandet av ett företag. Detta kommer av att man på detta vis belyser problemet från flera infallsvinklar vilket ytterligare klargör de hinder som kan uppkomma eller har uppstått.
55

Conceptual design of multi-domain systems: products and materials

Dietz, Timothy Paul 08 April 2010 (has links)
A key challenge facing designers creating innovative products is concept generation. Conceptual design is more effective when the design space is broadened by using an integrated design of product and material concepts approach. Conceptual design can also be accelerated by including problem solving and solution triggering tools in its structure. In this approach, structured analogy is used to transfer underlying principles from a solution suitable in one domain (i.e., product or mechanical domain) to an analogous solution in another domain (i.e., material domain). The nature of design analogy does not require as full of an exploration of the target domain as would otherwise be necessary; affording the possibility of a more rapid development. The addition of problem solving and solution triggering tools to a design method also decreases the design time and/or improves the quality of the final solution. This approach is formulated through a combination of the Theory of Inventive Problem Solving (TRIZ) proposed by Altshuller, and the systematic approach of Pahl and Beitz, for products that are jointly considered at the product and material level. These types of problems are ones where customer performance requirements are fulfilled through both the designed product and the designed material. The systematic approach of Pahl and Beitz is used as the base method through which TRIZ is used as a means of transferring abstract information about the design problem between the domains with the aim of accelerating conceptual design. This also allows for multi-domain design tools such as Su-Field-Model integration with design repositories for the transfer of information at different levels of abstraction; expanding the design space and effectively directing the designer. The explanation of this approach is presented through a simple example of a spring design improvement and validated through concept generation of a reactive material containment system.
56

New Techniques for Sample Preparation in Analytical Chemistry : Microextraction in Packed Syringe (MEPS) and Methacrylate Based Monolithic Pipette Tips

Altun, Zeki January 2008 (has links)
Sample preparation is often a bottleneck in systems for chemical analysis. The aim of this work was to investigate and develop new techniques to address some of the shortcomings of current sample preparation methods. The goal has been to provide full automation, on-line coupling to detection systems, short sample preparation times and high-throughput. In this work a new technique for sample preparation that can be connected on-line to liquid chromatography (LC) and gas chromatography (GC) has been developed. Microextraction in packed syringe (MEPS) is a new solid-phase extraction (SPE) technique that is miniaturized and can be fully automated. In MEPS approximately 1 mg of sorbent material is inserted into a gas tight syringe (100-250 μL) as a plug. Sample preparation takes place on the packed bed. Evaluation of the technique was done by the determination of local anaesthetics in human plasma samples using MEPS on-line with LC and tandem mass spectrometry (MS-MS). MEPS connected to an autosampler was fully automated and clean-up of the samples took about one minute. In addition, in the case of plasma samples the same plug of sorbent could be used for about 100 extractions before it was discarded. A further aim of this work was to increase sample preparation throughput. To do that disposable pipette tips were packed with a plug of porous polymer monoliths as sample adsorbent and were then used in connection with 96-well plates and LC-MS-MS. The evaluation of the methods was done by the analysis of local anaesthetics lidocaine and ropivacaine, and anti-cancer drug roscovitine in plasma samples. When roscovitine and lidocaine in human plasma and water samples were used as model substances, a 96-plate was handled in about two minutes. Further, disposable pipette tips may be produced at low cost and because they are used only once, carry-over is eliminated.
57

A Probing System with Replaceable Tips for Three Dimensional Nano-Metrology

Mrinalini, R Sri Muthu January 2017 (has links) (PDF)
With increase in the number of three dimensional (3-D) nanometer-scale objects that are being either fabricated or studied, there is a need to accurately characterize their geometry. While the Atomic force microscope (AFM) is a versatile tool for performing nano-metrology, it suffers from issues of poor accessibility of 3-D features and inability to measure 3-D forces that limit its applicability in 3-D nano-metrology. This thesis investigates the design and development of a novel probing system based on AFM that improves accessibility and enables direct measurement of 3-D forces acting on the AFM tip. Two approaches are investigated to address the issue of poor accessibility. The first is to develop a novel system that enables in-situ replacement and reuse of specialized AFM tips that improve accessibility, and the second is to design a special AFM tip that can actively re-orient about two independent axes. In order to perform in-situ tip replacement, a liquid meniscus based micro-gripper is developed and integrated on to a conventional AFM probe. The stiffness of the gripper is analyzed and shown to be adequately high along all three axes for AFM imaging to be performed. Tip replacement and re-use are both experimentally demonstrated by employing a novel tip-exchange station. The replaced tips are employed to show artifact-free AFM imaging of a standard calibration grating in both tapping-mode and contact-mode. To actively re-orient a conventional tip, a novel magnetically-actuated micro-scale ball-and-socket joint is integrated onto an AFM probe. The quasi-static behavior of the joint is experimentally characterized, and the ability of the tip to independently re-orient about two axes is demonstrated. The achieved range is about +/- 90 degrees about both X- and Y-axes. In order to realize the potential of the proposed probes for 3-D nano-metrology, an AFM is developed in-house that possesses the capability to make direct measurement of 3-D forces. Optimization of the measurement system to achieve identical sensitivities and resolution along all three axes is studied. Subsequently, the necessary electronics for measurement, actuation and control are developed. All the subsystems are experimentally calibrated and integrated. The overall AFM is shown to have a resolution of about 0.2 nm when operated in tapping-mode. The developed AFM is employed to showcase the following applications: characterization of the coefficient of kinetic friction of Muscovite mica, force controlled nano-scribing on polymethyl methacrylate (PMMA) and tapping-mode imaging of a calibration grating with the developed re-orientable AFM probe. Finally, the unique ability of the re-orientable AFM probe to control its tip-orientation is employed to develop a nanometer-scale coordinate measurement machine (CMM). The developed nano-CMM is shown to access the vertical wall of a sample and obtain its topography.
58

Fabricação e caracterização eletrica de ponteiras de emissão de campo recobertas com filme fino DLC (Diamond Like Carbon) / Fabrication and electrical characterization of field emission tips covered by DLC (Diamond Like Carbon) thin films

Porto, Lesnir Ferreira 20 December 2005 (has links)
Orientador: Marco Antonio Robert Alves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e Computação / Made available in DSpace on 2018-08-05T19:44:58Z (GMT). No. of bitstreams: 1 Porto_LesnirFerreira_M.pdf: 4190794 bytes, checksum: 1dec9fdc0b3dd1bffb34d78bccf2648b (MD5) Previous issue date: 2005 / Resumo: Este trabalho de mestrado teve como objetivos a fabricação e o estudo do comportamento elétrico das ponteiras de silício de emissão de campo a vácuo (PECV) recobertas com filme fino de carbono tipo diamante (DLC). Apresentamos o processo de fabricação das ponteiras de silício que é realizado através das etapas de fotolitografia, corrosão por íon reativo no plasma de SF6 (hexafluoreto de enxofre), oxidação térmica seca para afinamento, e deposição do filme DLC por PECVD (Plasma Enhanced Chemical Vapor Deposition). Mostramos os resultados obtidos da caracterização elétrica das ponteiras sem o filme e com o filme DLC, através do levantamento das curvas características I x V (corrente x tensão) e I x t (corrente x tempo). Verificamos que as curvas I x V obedeceram ao modelo de emissão de elétrons de Fowler-Nordheim. Comparamos estes resultados a fim de avaliarmos as mudanças na tensão de limiar, corrente emitida, e estabilidade de emissão. Neste estudo fabricamos PECV recobertas por filme DLC com espessura de aproximadamente 170 Å / Abstract: The objectives of this dissertation were the fabrication of silicon field emitter tips coated with diamond like carbon (DLC) thin films, and the study of its electrical behavior. We present the fabrication process of silicon tips that consists on four stages: photolithography, reactive ion etching SF6 plasma, thermal oxidation for sharpening, and the DLC deposition by PECVD (Plasma Enhanced Chemical Vapor Deposition). We show results obtained from the electrical characterization of tips without film and tips with DLC, by the characteristics curves I x V (current x voltage) and I x t (current x time). Current-voltage measurements followed a Fowler-Nordheim electron emission behavior. We compare these results to evaluate the change of the threshold voltage, emitted current, and emission stability, as a function of the coating with the film. In this study we fabricated silicon tips coated with DLC film with thickness of approximately 170 Å / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica
59

Aldolisation des alpha-trialkylsilyl-alpha-diazoacétones induite par l'ion fluorure / Fluoride induced aldol reaction of α-trialkylsilyl-α-diazoacetones

Abid Walha, Imen 17 January 2017 (has links)
Les composés diazocétoniques sont des intermédiaires utiles en synthèse organique et l’élaboration de motifs diazocarbonylés est à ce titre un enjeu important. Les diazocétones terminales peuvent subir une addition sur des aldéhydes dans des conditions basiques pour conduire de façon convergente à des composés béta-hydroxy-alpha-diazocétoniques à fort potentiel synthétique. Dans ce contexte, notre projet visait à promouvoir ce type de réaction dans des conditions douces et peu basiques. La stratégie adoptée reposait sur l’utilisation des alpha-trialkylsilyl-alpha-diazoacétones et leur activation nucléophile spécifique par un ion fluorure. Dans un premier temps, la synthèse de la TES-diazoacétone a été optimisée, puis une étude approfondie des paramètres réactionnels a permis la mise au point de la réaction d’aldolisation de la TES-diazoacétone, induite par le TBAF. Deux protocoles expérimentaux faciles de mise en œuvre ont ainsi été mis en place pour conduire à une large gamme de béta-hydroxy-alpha-diazoacétones avec des rendements élevés. L’extension asymétrique de cette méthodologie a ensuite été étudiée en mettant en jeu un fluorure d’ammonium chiral dérivé d’alcaloïde de Cinchona conduisant à la formation des premières béta-hydroxy-alpha-diazoacétones énantioenrichies (e.e = 35%) avec des rendements élevés. Enfin, cette méthodologie a été étendue avec succès à la TIPS-diazoacétone. La robustesse du groupement protecteur TIPS permet d’envisager une large gamme de transformations synthétiques « methyl-side », sans induire une désilylation partielle de la position azométhine du diazo-aldol. Ceci ouvre la voie à l’exploration future de la réactivité des diazoaldols TIPS. / Diazoketones are valuable intermediates in organic synthesis and the elaboration of α-diazocarbonyl scaffolds has aroused a steady interest for many years. The terminal diazoketones can be added to aldehydes under basic conditions to produce beta-hydroxy-alpha-diazoketone compounds with a high synthetic potential. In this context, our project aimed at promoting this type of reaction under mild conditions without using a base. The strategy adopted was based on the use of α-trialkylsilyl-α-diazoacetones and their specific nucleophilic activation by a fluoride ion. Initially, the synthesis of α-trialkylsilyl-α-diazoacetone was optimized and then, an extensive study of the reaction parameters allowed the development of an efficient aldolisation of TES-diazoacetone induced by TBAF. The nucleophilic, weakly basic conditions employed tolerate a wide range of substrates and constitute a practical high-yielding experimental procedure. The asymmetric extension of this methodology was then studied by using a chiral ammonium fluoride derived from Cinchona alkaloid. The condition set up allowed to elaborate the first enantioenriched beta-hydroxy-alpha-diazoacetones (e.e = 35%) in high yields. Finally, this methodology was successfully extended to TIPS-diazoacetone. The robustness of the TIPS protective group makes it possible to envision a range of synthetic « methyl-side » transformations without desilylation of the azomethine position of the diazo-aldol. This study paves the way for future exploration of the reactivity of TIPS diazoaldols.
60

Tvorba inovačních zadání a jejich řešení / Theory of inventive problem solving

Lněnička, Luboš January 2012 (has links)
This thesis deals with methodology for creating innovative concepts and their solving. More precisely, TIPS methodology „Theory of inventive problem solving“. This thesis is divided into four parts. In the first part, this methodology and its five basic tools are introduced. The second part provides introduction of software Goldfire Inovator including the tools which could be useful for students working on their projects. Third part demonstrates TIPS methodology on the innovation of wind power plant supported by software Goldfire Inovator. The fourth part evaluates advantages and contributions of TIPS methodology for education and practice.

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