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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.
401

Classificação dos exercícios do Jump Fit a partir de parâmetros relativos ao impacto

Schiehll, Paulo Eduardo January 2007 (has links)
As lesões decorrentes da prática da ginástica desde o início dos anos 70 tem aumentado a atenção dos pesquisadores. Tem sido documentado por diversos autores que 43 % dos praticantes e 76 % dos instrutores de aeróbica de alto impacto sofrem lesão, sendo que o impacto da aterrissagem é um dos momentos de maior risco nos membros inferiores em muitas destas modalidades terrestres. Diante disso, percebe-se a necessidade de estudos específicos que analisem adequadamente o comportamento do impacto durante aulas de ginástica inclusive na modalidade de ginástica JUMP FIT®. Objetivo deste estudo foi classificar os exercícios do JUMP FIT® a partir de parâmetros relativos ao impacto. Participaram sessenta professores de ambos os sexos, com mínimo de 6 meses de experiência na modalidade JUMP FIT®. Para a aquisição dos dados da força de reação do solo o minitrampolim foi instrumentado com 6 células de carga marca HBM, modelo PW 10 D1. O presente estudo mostrou que existe simetria na FRS entre os lados direito e esquerdo, com maiores valores para o lado esquerdo, apenas nos exercícios femoral simples e elevação de joelhos. Os mecanismos que levam a estas assimetrias ou mesmo suas conseqüências sobre o sistema músculoesquelético permanecem desconhecidas. Apartir dos resultados obtidos, sugere-se uma classificação associada ao pico de força e outra associada à taxa de aplicação de força. / The injuries due to the practice of the gymnastics since the beginning of 70´s have increased the attention of researchers. It has been documented for diverse authors that 43% of who practices and 76% of the aerobics’ instructors of high impact suffer injury, and the impact of the landing is one of the moments of major risk in the lower limbs in many of these terrestrial modalities. Because of this, it is perceived the necessity of specific studies that adequately analyze the behavior of the impact during lessons of gymnastics also in the modality of gymnastics JUMP FIT®. The aim of this study was to classify the exercises of JUMP FIT® from parameters related to the impact. Participated of this study sixty professors of both sex, with minimum of 6 months of experience in modality JUMP FIT®. For the acquisition of the data of the reaction force of the ground the mini springboard was instrumented with 6 mark’s cells HBM, model PW10 D1. The present study showed that exist symmetry in the FRS between the left and the right sides, with bigger values for the left side, only in the exercises simple femoral and elevation of knees. The mechanisms that take to these asymmetrical or even the consequences on the system skeletal-muscle remain unknown. From the obtained results we suggest a classification related to force peak and another to force load rate.
402

Quando o dinheiro compra mais felicidade? : o papel da self-regulation na felicidade de consumidores com experiências e bens materiais

Gonçalves, Manuela Albornoz January 2009 (has links)
Estudos anteriores sugeriram que as compras de experiências, tais como viagens e shows, deixam as pessoas mais felizes do que compras materiais, como, por exemplo, roupas e eletrônicos. E, por esta razão, sugerem que as pessoas passem a alocar mais a sua renda discricionária em tais tipos de compra. Entretanto, acredita-se que isto não é verdade para todos os indivíduos. O nível de felicidade com cada tipo de compra, provavelmente, varie de acordo com o estado motivacional das pessoas. À luz da teoria de self-regulation, hipotetizase que a felicidade derivada das compras depende da adequação entre as diferentes orientações motivacionais (prevention x promotion) e o tipo de compra (experiência x material). Em um estudo experimental, manipulou-se o tipo de compra e o regulatory focus, e se descobriu que os participantes com promotion focus, realmente, são mais felizes com as compras de experiência, no entanto, os participantes com prevention focus são tão felizes com as compras materiais quanto com as de experiência. Em um segundo estudo experimental, testou-se como os participantes com diferentes estados motivacionais alocam sua renda discricionária de modo a se sentirem mais felizes. Dado os resultados, sugere-se que os participantes com promotion focus são os que devem melhorar sua forma de investir para ficarem mais felizes, estes sim devem seguir a recomendação à experiência. Ainda, quando o trade-off entre os tipos de compra (experiência e material) estava saliente, os participantes com prevention focus, na seqüência, avaliaram as experiências mais favoravelmente do que quando o trade-off não estava saliente. / Experiential consumption - which is made with the primary intention of acquiring a life experience - usually yields greater happiness than material purchases. However, it might not be true for all individuals. The level of happiness in each type of purchase may vary according to one's motivational state. Building on research on subjective well-being and regulatory focus it is being put forward a hypothesis that happiness derived from purchases depends on the fit between self-regulation (individual differences) and the type of purchase (experiential versus material). In the first experimental study, the regulatory focus (prevention vs. promotion) and type of purchase (experiential vs. material) have been manipulated. The data shows that the promotion-focused participants indeed were happier with the experiential purchases than with the material ones. However, the prevention-focused participants were as happy with the material purchases as with the experiential purchases. In the second experimental study, it has been tested how the participants with different regulatory foci allocate their discretionary income as to feel happier. According to the results, its been suggested that in order to spend their income more judisciously, the promotion-focused participants should choose the experiential form of purchase and the prevention-focused participants should continue to invest in both types of purchases. Further, when the trade-off between the material and experiential purchases was made salient, experiences were subsequently evaluated more favorably than when the trade-off was not salient.
403

Distribution Fits for Various Parameters in the Hurricane Model

Oxenyuk, Victoria 20 March 2014 (has links)
The FPHLM is the only open public hurricane loss evaluation model available for assessment of hazard to insured residential property from hurricanes in Florida. The model consists of three independent components: the atmospheric science component, the vulnerability component and the actuarial component. The atmospheric component simulates thousands of storms, their wind speeds and their decay once on land on the basis of historical hurricane statistics defining wind risk for all residential zip codes in Florida. The focus of the thesis was to analyze atmospheric science component of the Florida Public Hurricane Loss Model, replicate statistical procedures used to model various parameters of atmospheric science component and to validate the model. I establish the distribution for modeling annual hurricane occurrence, choose the best fitting distribution for the radius of maximum winds and compute the expression for the pressure profile parameter Holland B.
404

Nonwork Role Importance as a Moderator to the Congruence-Satisfaction Relation

January 2016 (has links)
abstract: Individuals are attracted to occupational environments that align with their interests and personality characteristics (Holland, 1985, 1997). When an individual's attributes (i.e., needs, abilities, values and/or interests) align with the occupational environment's characteristics an individual is more satisfied. Past research suggests this relation is modest at best, hovering between .20 and .30 (Meyer et al., 2001, c.f. Wilkins & Tracey, 2014), with slightly higher estimates (ranging from .24 to .35) depending on how the variables of person and environment were measured (Kristof-Brown, Zimmerman, & Johnson, 2005). Several factors contribute to such low estimates, most notably the role of moderator variables in suppressing or exacerbating the true magnitude of this relation. A moderator that has yet to be explored is that of nonwork role priority, or the degree to which an individual's work identity is valued relative to other role identities. In the current study, three hypotheses were posited to investigate nonwork role priorities as a potential moderator to the congruence-satisfaction relation. Latent class analysis was used to apply a person-centered approach to understanding response patterns and differences in these roles. The sample was differentiated best by a two-class solution and the class variable in all three hierarchical regression models explained about five percent of the variance in job satisfaction, which suggests that work and nonwork role priority are meaningful to understanding individual career happiness. Class was not identified as a significant moderator to the congruence-satisfaction relation. Discussion of limitations to the current study and recommendations for future work in this area are presented. / Dissertation/Thesis / Doctoral Dissertation Counseling Psychology 2016
405

College Self-Efficacy and Academic Performance in Mexican American Undergraduates

January 2017 (has links)
abstract: Grounded in Social Cognitive Career Theory (SCCT; Lent, Brown, & Hackett, 1994, 2000), the current study examines environmental and person-cognitive variables as predictors of academic performance among a sample of 194 Mexican American undergraduate students. Specifically, this study used multiple regression analysis to test the associations between college self-efficacy (course self-efficacy and social self-efficacy), proximal contextual influences (campus climate and cultural fit), and gender on the academic performance (self reported grade point average, GPA). Results indicated that course self-efficacy was a significant predictor of academic performance for Mexican American undergraduate students. In addition, social self-efficacy, positive perceptions of the campus climate, and cultural fit were associated with high self-efficacy. This study contributes to our knowledge of college student development in general, and academic attainment among Mexican Americans specifically. Practice and research recommendations are discussed. / Dissertation/Thesis / Masters Thesis Counseling Psychology 2017
406

Goodness-of-fit tests in reliability : Weibull distribution and imperfect maintenance models / Tests d'adéquation en fiabilité : Loi de Weibull et modèles de maintenance imparfaite

Krit, Meryam 16 October 2014 (has links)
Ce travail porte sur les tests d'adéquation en fiabilité, à la fois pour les systèmes non réparables et les systèmes réparables. Les tests d'adéquation sont des outils efficaces pour vérifier la pertinence d'un modèle pour un jeu de données. Pour les systèmes non réparables, la loi exponentielle et la loi de Weibull sont les lois de durée de vie les plus utilisées en fiabilité. Une comparaison exhaustive des tests d'adéquation pour la loi exponentielle est présentée pour des données complètes et censurées, suivie par des recommandations d'utilisation de ces tests. La loi de Weibull à deux paramètres permet de modéliser des taux de hasard décroissants et croissants contrairement à la loi exponentielle qui suppose un taux de hasard constant. Cependant, il existe moins de tests d'adéquation à la loi de Weibull dans la littérature. Une revue exhaustive des tests existant est effectuée et deux familles de tests exacts sont preésentées. La première famille est la famille des tests basés sur la vraisemblance et la deuxième est la famille des tests basés sur la transformée de Laplace. Des propriétés asymptotiques des nouvelles statistiques de tests sont établies. Une comparaison complète des tests d'adéquation pour la loi de Weibull est effectuée. Des recommandations sur les tests les plus puissants sont données en fonction des caractéristiques du jeu de donnés testé. Pour les systèmes réparables, de nouveaux tests d'adéquation sont développés pour des modèles de maintenance imparfaite avec à la fois des maintenances correctives et des maintenances préventives déterministes. Ces tests sont exacts et peuvent être appliqués à des petits jeux de données. Finalement, des applications à de vrais jeux de données issus de l'industrie sont effectuées pour des systèmes réparables et des systèmes non réparables. / This work deals with goodness-of-fit (GOF) tests in reliability for both non repairable and repairable systems. GOF tests are efficient techniques to check the relevance of a model for a given data set. For non repairable systems, the Exponential and Weibull distributions are the most used lifetimes distributions in reliability. A comprehensive comparison study of the GOF tests for the Exponential distribution is presented for complete and censored samples followed by recommendations about the use of the tests. The two-parameter Weibull distribution allows decreasing and increasing failure rates unlike the Exponential distribution that makes the assumption of a constant hazard rate. Yet, there exist less GOF tests in the literature for the Weibull distribution. A comprehensive review of the existing GOF tests is done and two new families of exact GOF tests are introduced. The first family is the likelihood based GOF tests and the second is the family of tests based on the Laplace transform. Theoretical asymptotic properties of some new tests statistics are established. A comprehensive comparison study of the GOF tests for the Weibull distribution is done. Recommendations about the most powerful tests are given depending on the characteristics of the tested data sets. For repairable systems, new GOF tests are developed for imperfect maintenance models when both corrective maintenance and deterministic preventive maintenance are performed. These tests are exact and can be applied to small data sets. Finally, illustrative applications to real data sets from industry are carried out for repairable and non repairable systems.
407

Facilities management 'cultural fit' and the socialisation of external service provider employees in client organisations

Aderiye, Yetunde Oluwatoyin January 2015 (has links)
This thesis’ original contribution to knowledge is creating the awareness that facilities management (FM) departments and organisations do not consciously socialise external service provider staff into the client workplace and the development of a framework that can successfully achieve this integration. To provide a solid theoretical background for this framework, it reviews current literature on FM, outsourcing, organisational culture, and organisational socialisation. The aim of this study was achieved with the development of the ‘Cultural Fit’ framework which should go a long way in solving the research problem and answering the proposed question. The study was conducted as a qualitative multi-method design. This was selected because there were obvious gaps in socialisation especially in the FM industry. Qualitative methods are believed to provide richer data and this was adopted to begin closing those gaps through the provision of literary data. The research was conducted using the ethnographic approach because of the focus on culture and to maximise the qualitative approach. Interviews and focus groups are the qualitative methods used to collect this data. Reliability and validity are not always easy to verify but researchers have proposed several methods to improve them. This study employs the triangulation of more than one method of data collection, peer debriefing with colleagues, member checks by confirming the initial results during subsequent data collection and a rich, thick description. The major findings of this study are that organisational socialisation can be successful in socialising external service provider staff into the client workplace despite a current unawareness of its use. This study has developed a framework and guide that can be used to achieve this integration if client organisations and service providers work together to socialise external service provider staff.
408

Modelagem do desempenho separativo de ultracentrifugas por regressao multivariada com matriz de covariancia

MIGLIAVACCA, ELDER 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:48:58Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:51Z (GMT). No. of bitstreams: 1 09624.pdf: 7500503 bytes, checksum: 0fbfc877328a1063a37709866b6cefdc (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
409

Rörlighet i ländryggen, sittposition och förekomst av ländryggssmärta hos landsvägscyklister.

Djurback, Ingrid January 2018 (has links)
Bakgrund: Ländryggsmärta orsakad av överbelastning är vanligt inom cykelidrotten med en prevalens mellan 15 % -60 % hos landsvägscyklister på motions- och elitnivå. Vid sittande förändras ryggradens kurvatur vilket gör att belastningen förändras och det ger obalanser och större risk för smärta och skada än vid stående och gående. Sittpositionen på cykeln kan anpassas genom justering av cykeln, även kallad bike fit. Det finns få vetenskapliga studier hur denna anpassning ska ske för att undvika ryggsmärta. Syfte: Syftet med studien var att undersöka hur strukturer i ländryggen och säte/ben påverkar sittposition och förekomsten av ländryggssmärta vid landsvägscykling. Metod: Totalt 33 deltagare analyserades för hamstringslängd, total lumbal flexion samt sittposition på cykeln. Deltagarna tillfrågades angående erfarenheter av ländryggssmärta vid cykling. Resultat: Studien kunde påvisa en signifikant korrelation (r=0,57, P= 0,00082) mellan sittposition på cykeln samt total lumbal flexion. Hamstringslängd eller lumbal flexion på cykel visade sig ej korrelera med ländryggssmärta på cykel. Ingen skillnad förelåg mellan de cyklister som rapporterat ländryggssmärta eller ej gällande total lumbal flexionsrörlighet, lumbal flexion på cykeln eller hamstringslängd visades. Konklusion: Rörlighet i ländryggen och position på cykel verkar inte ensamt kunna förklara förekomst av cykelrelaterad ländryggssmärta. Hamstringslängden tycks inte påverka sittposition eller ländryggssmärta vid cykling.
410

Influência dos parâmetros envolvidos no processo de união por interferência de tubos por cravamento eletromagnético

Geier, Martin January 2014 (has links)
A união por conformação eletromagnética de perfis tubulares de alta condutividade elétrica é um processo inovador e limpo que pode substituir com sucesso os processos convencionais de união baseados na fixação mecânica por parafusos, rebites, soldagem e adesivos estruturais. Esta tecnologia funciona a temperatura ambiente, permite a união de materiais diferentes e oferece potencial para promover novas aplicações na montagem de estruturas leves. Neste trabalho busca-se compreender a união por interferência de tubos por cravamento eletromagnético em termos de seus principais parâmetros com o objetivo de identificar a influência na resistência global das uniões e estabelecer a faixa útil de condições operacionais do processo. Inicialmente são apresentados os fundamentos teóricos do processo de conformação eletromagnética e suas principais variantes operacionais, seguido de um resumo do estado atual do conhecimento da aplicação desta tecnologia na união de perfis tubulares no qual é verificado que os parâmetros mecânicos são a tensão residual no mandril, a área e forma da zona de união e o coeficiente de atrito entre os componentes. Entretanto, tais parâmetros estão relacionados de forma complexa com o processo de cravamento eletromagnético, a começar pela energia e a distribuição do pulso de pressão magnética gerados pela máquina e ferramenta que “disparam” o processo de conformação, a folga inicial entre componentes, o material dos componentes e, a geometria, forma e rugosidade do mandril. O estudo experimental foca a união por interferência de tubos de alumínio (AA6082-O) com mandris de aço (AISI 1045) e alumínio (AA6082 nos estados O e T6) investigando de forma gradual a influência de parâmetros do processo na resistência mecânica (à tração) deste tipo de uniões. Os resultados obtidos demonstram que a resistência mecânica da união e os modos de falha associados são diretamente relacionados com os parâmetros de processo e condições do mandril. Além disso, outras importantes contribuições são apresentadas em relação à instrumentação para medição de fluxo magnético e eficiência global do processo e para o desenvolvimento e aplicações industriais desta tecnologia. / Joining of tubular profiles with high electrical conductivity by electromagnetic forming (EMF) is an innovative and clean technology that can successfully replace conventional joining technologies based on mechanical fixing with fasteners, rivets, welding and structural adhesives. The technology works at room temperature, allows joining dissimilar materials and offers potential to foster new applications in the assembly of lightweight tubular frame structures. This work investigates the interference-fit joining of tubes by electromagnetic crimping in terms of its major parameters with the aim of identifying their influence on the overall strength of the joints and establishing the useful range of process operating conditions. Initially, the theoretical principles of EMF and its main operational process variants are presented, followed by a summary of the current state of the knowledge of its application in the joining of tubular profiles in which it is found that the mechanical parameters are the residual stress at the joint interface, the area and shape of the joint interface and the friction coefficient between the joining partners. However, these parameters are related in a very complex way with the electromagnetic crimping process parameters, starting with the charging energy and by the machine and tool which generates the distribution of the magnetic pressure pulse that “triggers” the forming process, the initial gap between joining partners, the mandrel properties such as material, geometry, shape and surface roughness. The experimental study focuses the interference-fit of aluminum tubes (AA6082-O) on mandrels made of different materials and metallurgical conditions (AISI 1045, AA6082-O and AA6082-T6) and, therefore, the process is analyzed by the gradual influence of other process parameters aiming to achieve high strength joints. Results show that the joint strength and the associated failure mechanisms are directly related to process parameters and mandrel conditions. In addition, other important contributions are presented regarding the instrumentation for measuring the magnetic flux and overall process efficiency and to the development and implementation of this technology in industrial processes.

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