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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.
61

Uso de coentro e sorgo granífero em cultivo de tomate orgânico visando ao aumento de insetos predadores e polinizadores / Coriander and sorghum use aiming to increase insect predators and pollinators in organic tomato

Santos, Laís da Conceição dos [UNESP] 30 May 2016 (has links)
Submitted by LAÍS DA CONCEIÇÃO DOS SANTOS null (laisc_santos@yahoo.com.br) on 2016-06-20T22:21:07Z No. of bitstreams: 1 Tese_Laís_da_Conceição_dos_Santos.pdf: 1686749 bytes, checksum: 6e7427e1641edd7e01def546c8b2617f (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-06-22T13:58:16Z (GMT) No. of bitstreams: 1 santos_lc_dr_jabo.pdf: 1686749 bytes, checksum: 6e7427e1641edd7e01def546c8b2617f (MD5) / Made available in DSpace on 2016-06-22T13:58:16Z (GMT). No. of bitstreams: 1 santos_lc_dr_jabo.pdf: 1686749 bytes, checksum: 6e7427e1641edd7e01def546c8b2617f (MD5) Previous issue date: 2016-05-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo do presente estudo foi avaliar os efeitos da estratégia “pushpull” utilizando plantas de sorgo (Sorghum bicolor L.) e coentro (Coriandrum sativum L.) sobre insetos-praga e predadores e avaliar a abundância e riqueza de espécies de Coleoptera, Hemiptera e abelhas, em tomateiro orgânico cultivado em casa-devegetação. O experimento foi composto de dois tratamentos: a) policultivo e b) monocultivo de tomateiro. O policulivo compreendeu plantas de tomate, Solanum lycopersicum L., de coentro e sorgo. As avaliações foram quinzenais e realizadas desde o plantio até o fim do ciclo da cultura. Em cada parcela os insetos foram amostrados visualmente examinando-se toda a planta, considerando-se aleatoriamente 10 plantas de tomateiro, 10 plantas de C. sativum e 10 plantas de S. bicolor. O delineamento utilizado foi o de blocos casualizados com parcelas subdivididas no tempo (Split-Plot), com 12 repetições, sendo os tratamentos principais (parcelas) representados pelo mono e policultivo de tomateiro e os tratamentos secundários (subparcelas) representados pelas datas de coleta, sendo oito datas de coleta para cada safra. A presença de sorgo e coentro não reduz significativamente a densidade populacional de Tuta absoluta (Meirick) (Lepidoptera: Gelechiidae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Caliothrips phaseoli Hood (Thysanoptera: Thripidae) e Aphis gossypii Glover (Hemiptera: Aphididade) no tomateiro em casa-de-vegetação. O policultivo tomateiro-coentrosorgo favorece a ocorrência de insetos predadores, sobretudo após a floração do coentro, que proporciona a ocorrência de Franklinothrips vespiformis (Crawford) (Thysanoptera: Aeolothripidae). O coentro não possui efeito repelente sobre coleópteros e hemípteros fitófagos. A associação do coentro com o tomateiro em casa-de-vegetação contribui para a atração de insetos polinizadores. A diversificação vegetal promove aumento na abundância e riqueza de espécies de besouros e percevejos em tomateiro orgânico. / The objective of this study was to evaluate the effects of the strategy "push-pull" using sorghum plants (Sorghum bicolor L.) and coriander (Coriandrum sativum L.) on pests insect and predators and evaluate the abundance and species richness of Coleoptera, Hemiptera and bees in organic tomato. The experiment consisted of two treatments: a) polyculture; b) tomato monoculture. The polyculture was formed by tomato plants, Solanum lycopersicum L., coriander and sorghum. The evaluations were carried out fortnightly, from planting to end of crop cycle. In each plot the insects were sampled visually examining the whole plant, considering randomly 10 tomato plants, 10 plants of C. sativum and 10 plants of S. bicolor. The design was a randomized block with split plot in the time (Split-Plot) with 12 repetitions, the main treatments (plots) were represented by mono and tomato polyculture and secondary treatments (subplots) represented by the collection dates, having been evaluated eight dates in each crop cycle. The presence of sorghum and coriander did not significantly reduce the population density of Tuta absoluta (Meirick) (Lepidoptera: Gelechiidae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Caliothrips phaseoli Hood (Thysanoptera: Thripidae) and Aphis gossypii Glover (Hemiptera: Aphididade) in tomato in greenhouse. The tomato-coriander-sorghum polyculture favors the occurrence of insect predators, especially after flowering coriander. Coriander provides greater diversity of insect predators, especially Franklinothrips vespiformis (Crawford) (Thysanoptera: Aeolothripidae). Coriander has no repellent effect on phytophagous Coleoptera and Hemiptera in organic tomato cultivation. The plant diversification promotes increase in the abundance and species richness of beetles and hemipteran in organic tomato. The combination of coriander and tomato plants in greenhouse helps to attract pollinating insects. / CNPq: 140745/2016-5
62

Espectroscopia eletrônica e solvatação de cromóforos zwiteriônicos: um estudo ab initio

Maximiano Fernandes Pinheiro Junior, José 31 January 2009 (has links)
Made available in DSpace on 2014-06-12T18:02:03Z (GMT). No. of bitstreams: 2 arquivo2369_1.pdf: 4588742 bytes, checksum: 7359c39184a61c299104b1a396348c30 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pela simplicidade do tratamento teórico, fácil processabilidade, e possíveis aplicações em ciências dos materiais, oligômeros conjugados representam uma classe especial de compostos orgânicos. A substituição terminal dessas estruturas com grupos doadores (D) e aceitadores de elétrons (A) resulta em moléculas (D 􀀀 􀀀 A) com propriedades óticas e eletrônicas excepcionais. Em geral, estes sistemas são caracterizados por uma efetiva Transferência de Elétrons Intramolecular Fotoinduzida (TEIF). Por exemplo, betaínas são compostos D 􀀀􀀀 A que têm recebido uma atenção especial devido à grande redução do seu momento de dipolo após excitação eletrônica, o que induz uma intensa transferência de carga do grupo D para o A. Em particular, examinamos betaínas piridínicas, contendo uma longa ponte -conjugada, devido à sugestão de que podem exibir uma TEIF na direção inversa, isto é, do grupo A para o D, como consequência de uma mudança observada na localização dos orbitais moleculares de fronteira (OMFs) HOMO e LUMO. Inicialmente, confirmamos por método ab initio a existência de uma TEIF inversa em uma família representativa de betaínas piridínicas, e destacamos o papel fundamental desempenhado pela ponte conjugada. Estes resultados contribuem para a expectativa de que a TEIF inversa seja um efeito físico real e não um artefato do método utilizado. Estendemos nossa análise a um total de 88 oligômeros D􀀀()n 􀀀A pertencentes a 8 novas famílias distintas de moléculas, nas quais a inversão HOMO-LUMOfoi identificada. Verificamos ainda que os orbitais HOMO-i e LUMO+i (i=1,2 e 3) desses cromóforos também são suscetíveis a mudanças na localização espacial como função do tamanho da cadeia conjugada, devido a sucessivos pontos de cruzamento entre os níveis de energia destes orbitais. Em seguida, exploramos teoricamente os efeitos da mudança na localização espacial dos OMFs sobre as propriedades espectroscópicas das 88 estruturas examinadas. Por m, investigamos a influência do solvente sobre as propriedades eletrônicas e espectroscópicas de uma família de moléculas D 􀀀 ()n 􀀀 A derivados da Betaína-30 utilizando modelos de solvatação contínuos. Concluímos que a intensidade e a direção dos deslocamentos solvatocrômicos do espectro destes cromóforos dependem do comprimento da cadeia conjugada que conecta os grupos D e A, sugerindo uma possível forma de verificação experimental para o fenômeno de inversão HOMO-LUMO. Discutimos também, as possíveis aplicações deste efeito para o desenvolvimento de uma nova classe de dispositivos da Eletrônica Molecular em fase líquida.
63

Unga svenskars migration till Barcelona : En studie om åtta unga svenskars beslut samt upplevelser med sin flytt

Saume, Edra January 2017 (has links)
Studiens syfte var att undersöka unga svenskars anledningar samt erfarenhet av migration från Sverige till Barcelona, Spanien, och såvida de kan tänka sig att permanent bosätta sig utomlands. Forskning inom migration finns det gott om, dock saknas kvalitativa studier som fokuserar på svenska ungdomars motiv till utlandsflytten. Studiens teoretiska ramverk bygger på fyra perspektiv; ”Push-pullteorin” som handlar om olika faktorer som har dragit individen till den nya orten samt ifrån ursprungsorten, ”socialt nätverksteorin” som behandlar frågan om huruvida ens kontaktnätverk kan påverka beslut inför en sådan flytt, ”platsanknytningar” som berättar om hur vi känner inför olika platser och hur pass mycket man känner en anknytning till platsen ifråga sett ur olika dimensioner, samt ”identitet” där jag undersöker om informanternas identitetsbygge kan vara en drivkraft i beslutsprocessen. Studiens data består av 8 informanter som har intervjuats i Barcelona. Samtliga informanter är svenska kvinnor och män mellan 21–28 år. Studien visar att anledningen till deras flytt till Barcelona var att de behövde en ny start i livet. De ville hitta sig själv, utvecklas samt få uppleva något mer, något nytt. De förklarar att de flyttade ifrån Sverige för att få kunna vara vem man vill och göra vad man vill utan en massa normer som begränsar ens handlingsutrymme. Push-faktorer dominerade således i beslutsfattandet. Sociala nätverksteorin verkar ha en stor påverkan på deras flytt då alla har flera vänner som har flyttat utomlands. Nästan alla kunde tänka sig att permanent bosätta sig utomlands och det som då skulle vara den främsta orsaken var om de skulle inleda ett förhållande med någon som bor i utlandet. En annan anledning skulle vara jobbet/karriären.
64

Internationalization of Higher Education : Understanding the International Students' Choice of a Swedish University and the Decision-Making Process

Thiru, Prisca, Denisova, Aleksandra January 2020 (has links)
As the growth of Internationalisation of Higher Education shifts from former dominant nations like USA, Canada, England and Australia to other nations in Europe and Asia such as Germany, Sweden, Japan and Singapore, this study seeks to understand the decision-making process of an International Student looking to study at a Swedish University. Borrowing from previous studies, the ‘push and pull factors’ are used as the main theoretical reference as well as in discussion of the findings. Specific factors special to Sweden and the European Union in general such as visa policies and tuition fees are also discussed. For empirical data, international students already undertaking various master’s programmes as well as former master’s students at the Swedish university answer an online questionnaire pertaining to: decision to study abroad, decision to study in Sweden and decision to study at the particular Swedish University. Moreover, empirical data includes an interview with a representative of the university under analysis. In-depth analyses of data using Standard Deviation (SD), calculation of p value, ANOVA and Tukey’s tests are also performed to give clear comparisons of the various data sets such as ‘programme specialisation’ and ‘home country’ and their influence on the decision-making process. Personal satisfaction and better career prospects are identified as the major ‘push factors’. Programme quality and requirements, Sweden’s quality of life and health of environment, safe place to study, and location in the European Union are identified as main ‘pull factors’. It is found out that the home country of international students has a huge influence on their decisions to study abroad/ in Sweden/ at a certain university, although specialization also has influence, it appears to be drastically less. The findings have important implications in helping aspiring students make informed decisions as they consider choice of country and university, as well as implications for Higher Education Institutions as they respond to the demands created by globalisation of higher education, and subsequently endeavour to attract more international students through marketing or curriculum development of their programmes.
65

Filipina Nurses in the National Health Service: The push and pull factors behind international migration to the United Kingdom

Ford, Catherine January 2018 (has links)
No description available.
66

Design of a Passive Exoskeleton Spine

Zhang, Haohan 07 November 2014 (has links)
In this thesis, a passive exoskeleton spine was designed and evaluated by a series of biomechanics simulations. The design objectives were to reduce the human operator’s back muscle efforts and the intervertebral reaction torques during a full range sagittal plane spine flexion/extension. The biomechanics simulations were performed using the OpenSim modeling environment. To manipulate the simulations, a full body musculoskeletal model was created based on the OpenSim gait2354 and “lumbar spine” models. To support flexion and extension of the torso a “push-pull” strategy was proposed by applying external pushing and pulling forces on different locations on the torso. The external forces were optimized via simulations and then a physical exoskeleton prototype was built to evaluate the “push-pull” strategy in vivo. The prototype was tested on three different subjects where the sEMG and inertial data were collected to estimate the muscle force reduction and intervertebral torque reduction. The prototype assisted the users in sagittal plane flexion/extension and reduced the average muscle force and intervertebral reaction torque by an average of 371 N and 29 Nm, respectively.
67

Validation of the Religious Exit Push Pull Measure

Engelman, Joel 26 November 2019 (has links)
No description available.
68

Spínané zdroje ve vozidlech elektrické trakce / Switching source in electric tractions vehicle

Škunda, Michal January 2010 (has links)
The first part of this work describes the design and implementation of switch-mode power supply for control circuits for 12/2x24V 4.5A fuel cells. The introduction picks the issue of power sources in electromobiles and final design and implementation of switching power suply. The next part deals with the issues of fast-charger and generators for power transistors. It describes the structure of DC converter and control and protectin circuits of quick-charger. In the end this work describes selected driver circuits and charge tests on fast-charger as evidenced by measurements.
69

Optimisation du ConWip dans un environnement multiproduit / ConWip optimization in a multiprodut environment

Jaegler, Yann 07 December 2018 (has links)
Au cours de la dernière décennie, le système de contrôle de production (PCS) Constant Work InProgress (CONWIP) a été étudié par un nombre croissant de publications. Compte tenu des défis industrielsactuels, tels que la nécessité de s’adapter, la personnalisation croissante des produits, la réduction des délaiset l’importance grandissante du service rendu aux clients, le ConWip semble être un PCS efficace et agilepour les industriels. Cette thèse débute par une revue systématique des travaux sur le ConWip remontant à2003 basée sur une méthode de classification originale. Cette méthode permet de catégoriser les papiers quise concentrent sur le dimensionnement, la performance, le contexte d’implémentation et la comparaison avecd'autres PCS. En plus de proposer une clé de lecture pour interpréter les approches de recherche, les critèresconsidérés répondent à des questions sur la façon de mettre en oeuvre, la façon d’optimiser et les raisonspour lesquelles utiliser le ConWip. Une étude sur les pistes de recherche proposées ou applicables au ConWipa ensuite permis de mettre en évidence les plus prometteuses et d’en extraire les principales tendances.L'objectif consiste ici à mettre à jour les lacunes de la recherche existante sur le ConWip. L'une d'entre ellesamène à des questions clés liées à la mise en oeuvre du ConWip dans un environnement caractérisé par unmix produit élevé et/ou par un mix gamme opératoire élevé. Dans ce contexte, quatre algorithmes qui génèrentdifférentes gammes génériques sont ensuite présentés. Ces gammes, appelées « gammes enveloppes » sontimplémentées dans Wipsim, un outil d'ingénierie utilisé dans les projets de conception et d'amélioration deslignes d'assemblage ConWip, qui permet de calculer les paramètres ConWip optimisés pour chacune desgammes. Un échantillon de données, dérivé d'un cas industriel, est utilisé pour tester les quatre algorithmes.Nous les comparons à travers leur sensibilité au mix produit et selon l'impact induit par l'introduction dedifférents produits atypiques dans le mix. Nos expériences montrent que nos algorithmes génèrent desgammes enveloppes pertinentes et aident les praticiens à choisir le plus adapté à leur contexte spécifique. / In the past decade, a growing body of literature has investigated the CONstant Work InProgress (ConWip) production control system (PCS). In view of the current industrial challengesentailing adaptability, product customisation, decreas- ing leadtimes and customer satisfaction, ConWipseems to be an effective and adaptive PCS for manufacturers. A ConWip systematic review datingback to 2003 and provides a guide for understanding through an original classification method. Thismethod enables the differentiation of papers that concentrate on Con- Wip sizing, performance andcontext as well as a comparison with other PCSs. In addition to providing a key to interpreting theresearch approaches, the criteria considered answers questions on how to implement, how to optimiseand why and when to use ConWip. The survey of research avenues proposed or applicable to CONWIPclassify them, highlight the most promising and extract the main trends. The final aim is to provide somegaps. One of the them deals with key questions related to the implementation of ConWip in a highproduct mix and/or high routing mix environment. Four algorithms that generate different genericroutings are presented. These routings are implemented into Wipsim, an engineering tool used inprojects to design and improve ConWip assembly lines, which allows the optimized ConWip parametersfor each routing to be calculated. A sample of data, derived from an industrial case, is used to test thefour models. We compare them via their sensitivity to the mix product and through the impact of theintroduction of different, atypical products. Our experiments show that our algorithms generatedworthwhile generic routings and help practitioners choose among them, depending on a specificcontext.
70

Motivational factors among entrepreneurs

Williamsson, Vanessa January 2022 (has links)
There are several motivational factors for why entrepreneurs start a venture, continue to run the venture and also exit the venture. A prevalent theme in previous literature regarding entrepreneurial motivation, is the dichotomy of push and pull theory. This suggests that an entrepreneur can either be a necessity entrepreneur or an opportunity entrepreneur, meaning their motivation comes from either push or pull factors. Newer research argues that push and pull factors can co-exist and also change over time, highlighting that this dichotomy is ambiguous. However, this is still an under-researched area and many researchers call for more empirical findings concerning this topic. To gather more information regarding this disagreement, a qualitative study was executed, through semi-structured interviews with Swedish entrepreneurs from different entrepreneurial phases. The findings in this study indicate that motivational push and pull factors can be present simultaneously in an individual, and also change over time, depending on dynamic internal and external factors regarding the entrepreneur themselves and/or the venture.

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