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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Padrão de fixação dos salários e política monetária no Brasil

Silva, Gian Barbosa da 01 April 2013 (has links)
Submitted by Gian Silva (gian.economista@gmail.com) on 2013-05-15T14:33:02Z No. of bitstreams: 1 Dissertação.pdf: 894008 bytes, checksum: 93448fceb6721e0f54e5d8264ec33587 (MD5) / Approved for entry into archive by Suzinei Teles Garcia Garcia (suzinei.garcia@fgv.br) on 2013-05-15T20:03:54Z (GMT) No. of bitstreams: 1 Dissertação.pdf: 894008 bytes, checksum: 93448fceb6721e0f54e5d8264ec33587 (MD5) / Made available in DSpace on 2013-05-16T12:16:20Z (GMT). No. of bitstreams: 1 Dissertação.pdf: 894008 bytes, checksum: 93448fceb6721e0f54e5d8264ec33587 (MD5) Previous issue date: 2013-04-01 / Este estudo buscou incluir mais um ponto de dados às evidências que se acumulam a partir do trabalho de Olivei e Tenreyro (2007, 2010), que encontrou evidências empíricas sobre a importância da rigidez dos salários nominais sobre os efeitos reais da política monetária, explorando a ligação entre os diferentes padrões dos reajustes salariais encontrados nos países e o comportamento do produto e dos preços diante de choques de política monetária. Para o Brasil, inovações na política monetária que ocorrem no segundo trimestre ou no quarto trimestre provocariam uma resposta mais intensa do PIB do ponto de vista da significância estatística. Por outro lado, os choques monetários que ocorrem no primeiro ou no terceiro trimestre são associados a reações do produto com pouca significância estatística. Para a inflação, não foram conseguidas respostas estatisticamente significantes para nenhum tipo de trimestre. Incentivado por informações concretas sobre o calendário dos reajustes salariais, que sugerem a redefinição de uma grande fração dos salários entre março e maio e entre outubro e novembro, propomos uma possível explicação para as respostas diferenciadas baseadas em alteração concentrada dos contratos dos salários. / The aim of this study was to add another data point to evidence that accumulates from the work of Olivei and Tenreyro (2007, 2010), who found empirical evidence about the importance of nominal wage rigidity on the real effects of monetary policy, exploring the links between different patterns of wage adjustments found in the countries and behavior of the output and prices after monetary policy shocks. For Brazil, monetary policy innovations that occur in the second quarter or in the fourth quarter would cause a more intense response from GDP statistically. In contrast, monetary shocks that occur in first or in third quarter are associated with little reaction from GDP statistically. For inflation, the responses were not statistically significant for any kind of quarter. Based on specific information about the timing of wage changes, suggesting a redefinition of a large fraction of wages between March and May and between October and November, we propose a possible explanation for the different responses based on concentrated modification of contractual wages.
82

The Relationship Between Self-concept Structure And Behavioral Flexibility: A Model Relating Cognitive Structures To Behavioral Patterns

Engin, Elif 01 July 2004 (has links) (PDF)
Self-concept structure has been extensively studied in the literature especially with regard to its relationship with psychological adjustment. However, the behavioral outcomes of the cognitive structure of the self and the mechanisms through which the relationship between self-concept structure and psychological adjsutment operate are still to be maintained. This study offered that the two dimensions of self-concept structure, differention and integration, would be related to the two dimensions of behavioral flexibility: Behavioral repertoire and deliberate adjustment of behaviors. iv Differentiation, tapping behavioral repertoire, was assumed to determine whether a person is flexible or rigid, while integration tapping deliberate adjustment were supposed to determine the quality of flexibility (i.e., whether the repertoire is controlled by the individual or by situational factors). By crossing these two dimensions, a model with four behavioral patterns was proposed: (1) Functional flexibility, characterized by both high integration and high differentiation / (2) situational flexibility, characterized by high differentiation but low integration / (3) stereotypical rigidity, characterized by low differentiation but high integration, and (4) effacing rigidity, which is low on both dimensions. Three studies were conducted on university students (N = 163, N = 123 and N = 242 for the three studies respectively) in order to test this model. Results revealed that the behavioral repertoire dimension of behavioral flexibility was linked to selfconcept differentiation, whereas the deliberate adjustment dimension was related to selfconcept integration. Functional flexibility and effacing rigidity patterns were clearly specified by measures of psychological adjustment, locus of control, need for cognition, need for approval and Big Five dimensions. Stereotypical rigidity and situational flexibilty patterns, however, seemed to require more elaboration. The model offering that flexibility mediates the link between self-concept structure and self-esteem was not supported.
83

Návrh a optimalizace tělesa vřeteníku pro obráběcí stroj / Design and optimization of a headstock for machine tools

Lekeš, Petr January 2021 (has links)
This diploma thesis deals with the design and optimization of a headstock for machine tool. Thesis was focused to comparison of several types of slide-ways and linear guides of headstock, considering their static and dynamic rigidity. An overview in the field of machine tools, their static and dynamic properties, use materials and design of headstocks, considering types of guideways, types of guideways drives and types of drives of spindle was made. Among the other main goals is included design of several types of guideway of headstock for horizontal machine tool, elaboration of computational models and evaluation of results.
84

The immediate effect of thoraco-lumbar spinal manipulation compared to lower lumbar spinal manipulation on core muscle endurance and activity in patients with mechanical low back pain

Murray, Stuart M. January 2009 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban University of Technology, 2009. / Through the literature review it has become apparent that low back pain is a very real problem in most societies. It has been suggested that there is enough evidence to prove the relationship between low back pain and local muscle dysfunction and that focus in management of these patients should be the rehabilitation of these muscles by exercise. Literature suggests that optimal core muscle strength, control and endurance working synergistically with the rest of the neuromusculoskeletal system is necessary for lumbar spine stability . Arthrogenic Muscle Inhibition is caused by distension and/or damage of a joint and is thought to disable the muscle from contracting all its muscle fibres. When a joint is injured it is thought that AMI causes muscle weakness, which in turn hampers the rehabilitation process of that joint despite complete muscle integrity. Spinal manipulative therapy has been shown to alter the excitability of spinal muscle motor neurons due to the stimulation of mechanoreceptors in the joint capsules suggesting that SMT could be a means to remove this inhibitory action. The literature supports the hypothesis that a decrease in the neurological deficit caused by AMI may result in a faster recovery rate. Aims The aim of this study is to determine the immediate effect of thoraco-lumbar spinal manipulation compared to lower lumbar spinal manipulation on core muscle endurance and activity in patients with mechanical low back pain by assessing the correlation between the objective and subjective measures. Method A prospective, convenience sample with purpose allocation (pre /post) clinical trial was used as the sampling method. Thirty participants where placed in two groups, group one and group two, of fifteen people each. Group one underwent spinal v manipulative therapy between L4 and S1 spinal levels. Group two underwent spinal manipulative therapy in between T8 and L1 spinal levels. The objective and subjective testing was done pre- and post-intervention. The objective data was that of a surface EMG attached bilaterally over the internal oblique as well as a prone abdominal draw in biofeedback test. The subjective data included a pain numerical rating scale (0-100). Results The results showed to partially favour group two (thoraco-lumbar), in both increased endurance time that would prove that AMI does in fact inhibit the transversus abdominis and obliques internus, thus it would hinder the rehabilitative process. Some of the statistics where not in favour of the aims, as there was no difference in the effect of group one or two on the NRS, as both improved consistently. It would be recommended that use be made of fine-wire EMG for testing the activity in both the obliques internus and the transversus abdominis, which would allow for more consistent readings, thus adding strength to the research.
85

The relative effect of proprioceptive neuromuscular facilitated stretching immediately after eccentric exercise vs proprioceptive neuromuscular facilitated stretching post delayed onset muscle soreness in healthy, sedentary male subjects

Schlebusch, Helen Beverleigh January 2007 (has links)
Dissertation submitted in fulfillment of requirements for a Master's Degree in Technology: Chiropractic, Durban University of Technology, 2007. / Delayed onset muscle soreness (DOMS) is muscular pain which ranges from mild discomfort to severe debilitating pain, caused by eccentric exercise. It generally sets in 12 - 24 hours after the causative activity and subsides within approximately seven days. The aim of this study was to determine whether proprioceptive neuromuscular facilitated (PNF) stretching immediately after eccentric exercise was more beneficial than PNF stretching 24 hours after eccentric exercise on the muscle pain experienced in DOMS. This study was a prospective, randomised clinical trial. Thirty healthy sedentary male participants were randomly selected to participate in the study by advertising in local newspapers and pamphlet distribution in Durban and its surrounding areas. The patients' ages ranged from 20 to 32 years of age. Subjective and objective readings were taken at the beginning and end of each visit, over the three-day study period. This was done with the numerical pain rating scale and the algometer force gauge, respectively. Baseline measurements were taken before any exercise or stretching at the initial visit. All participants then were asked to do squats until fatigue to induce delayed onset muscle soreness. III The participants were divided randomly into two groups, Group A and Group B. The former group underwent PNF stretching immediately after exercise and the latter group underwent PNF stretching twenty four hours after exercise. Both groups were asked to return for two subsequent days following the initial visit and they again underwent PNF stretching at each visit. Comparison was made between the individual patients' pain perception over time, as well as between each group. Descriptive analysis was done using frequency tables (reporting counts and percentages) for categorical variables and summary statistics (reporting mean, standard deviation and range), for quantitative variables. Baseline and demographic characteristics were compared between the two treatment groups using independent t-tests for quantitative variables and Pearson's chisquare tests for categorical variables. The treatment effect was assessed using repeated measures ANOVA testing. Statistical analysis revealed that there was no difference in the improvement of pain experienced between the two groups. However, Group B (PNF stretching 24 hours after exercise) appeared to improve at a greater rate than Group A (PNF stretching immediately after exercise). A larger study needs to be conducted in order to provide statistically relevant results. / M
86

A cross sectional cohort pilot study of the activation and endurance of the transversus abdominis muscle in three populations

Ferguson, Sarah Kim January 2007 (has links)
A dissertation submitted in partial compliance with the requirements for the Master's Degree of Technology: Chiropractic, Durban University of Technology, 2007. / The Transversus Abdominis (TrA) muscle is recognised in the literature as playing a vital and protective role in maintaining a healthy core and aiding lumbar biomechanics in the dampening of external forces applied to the lumbar spine. Pilates purports to employ the principles of core training yet there remains a deficit in the literature despite its popularity in rehabilitation and fitness industries. This study aimed to evaluate the efficacy of Pilates method in training the TrA in comparison to a moderately active population that regularly exercises in a gym environment, as well as a sedentary control. / M
87

Robotic Evaluation Of Rigidity In Parkinson's As A Function Of Speed-Comparison To Clinical Scales

Saidi, Azadeh 01 January 2005 (has links)
Rigidity is one of the cardinal symptoms in Parkinson's disease, along with Bradykinesia, tremor and postural instability. Rigidity in PD has been understudied, but its pathophysiological basis remains unclear. Various types of neurophysiological and biomechanical approach have been developed in order to investigate the neural control of muscle tone. A common approach is to observe the sensitivity of muscle resistance in response to stretch velocity or displacement [Kamper, Rea, He]. A recent study on elbow flexors in patients with spasticity and rigidity showed a velocity dependent increase in reactive torque in both groups [Lee H, et al). Even though this Study shows a correlation between elbow flexors and velocity, it doesn't discuss the role of elbow extensors. We studied the rigidity response in the elbow of both arms to different speed movements in 12 patients suffering from Parkinson's disease ON or OFF medication. The purpose of this study was to look at both elbow flexion and extension and show that quantitative measures of rigidity and movement disorders in subjects with Parkinson's disease correlate with the currently used clinical evaluations and also find the correlation between velocity and both elbow extension and flexion at the same time. Elbow was flexed and extended by means of a robotic arm,under four different speeds. The resistance to movement was recorded with a torque sensor and EMG of two elbow muscles; Biceps and Triceps; was recorded while the subjects were attempting to relax. The patients were also examined by physicians and their elbow rigidity and muscle tone and Parkinson's disease stage was evaluated and a Universal score in the categories of UPDRS, MMSE, and CAPIT was assigned for each arm of each individual. In the end we will argue that there is a very strong correlation between speed and elbow Extension and Flexion, muscle activity and the rigidity presented in each arm. We will also present the correlation between the robotic torque measurement and the clinical scores given to each subject.
88

Profinite Completions and Representations of Finitely Generated Groups

Ryan F Spitler (7046771) 16 August 2019 (has links)
n previous work, the author and his collaborators developed a relationship in the SL(2,C) representation theories of two finitely generated groups with isomorphicprofinite completions assuming a certain strong representation rigidity for one of thegroups. This was then exploited as one part of producing examples of lattices in SL(2,C) which are profinitely rigid. In this article, the relationship is extended to representations in any connected reductive algebraic groups under a weaker representation rigidity hypothesis. The results are applied to lattices in higher rank Liegroups where we show that for some such groups, including SL(n,Z) forn≥3, they are either profinitely rigid, or they contain a proper Grothendieck subgroup.
89

Avaliação do efeito da rigidez estrutural sobre a dinâmica veicular. / Evaluation of the effect of structural stiffness on the dynamic vehicle.

Botosso, Antônio Carlos 27 May 2015 (has links)
O trabalho desenvolvido tem como objetivo avaliar a influência da rigidez estrutural no comportamento dinâmico do veículo baseando-se em manobra de raio constante em condição quase estática e análise de sensibilidade através de simulação numérica computacional. São apresentados dois modelos para avaliar a transferência de carga lateral do veículo quando sujeito à aceleração lateral (manobra de raio constante), um modelo completo de veículo elaborado em ambiente multicorpos tendo a carroceria e o sub-chassi modelados como corpos flexíveis, e outro modelo analítico com a consideração da rigidez torcional (obtida de modelo de elementos finitos) da estrutura. Com o modelo analítico atendendo o nível de correlação necessário para o propósito deste trabalho, discute-se neste ponto as variações na transferência de carga devido à rigidez torcional da estrutura. Em seguida, com o intuito de abranger, além do parâmetro de transferência de carga lateral, quais comportamentos do veículo são afetados pela sua rigidez estrutural, é proposta a utilização do método de engenharia robusta para a identificação das condições externas que geram diferentes resultados de comportamento dinâmico do veículo com a variação da rigidez estrutural. Este estudo permite identificar manobras ou situações nas quais as considerações de flexibilidade estrutural num modelo multicorpos, ou mesmo numa condição física real, são relevantes e podem afetar a segurança, dirigibilidade e o conforto do veículo. / The work aims to evaluate the influence of structural stiffness on the dynamic behavior of the vehicle based on a constant radius maneuver in a quasi-static condition and a sensitivity analysis through computer numerical simulation. Two models were developed to evaluate the lateral load transfer of the vehicle when subjected to lateral acceleration (constant radius maneuver), a complete vehicle built in multibody environment with the body and the sub-chassis modeled as flexible bodies, and an analytical model with consideration of structure torsional stiffness (obtained from finite element model). With the analytical model presenting the required correlation for the purpose of this paper, we discuss, at this point, the lateral load transfer variations due to torcional structural stiffness. Then, in order to cover, in addition to lateral load transfer, how the vehicle behavior is affected by its structural stiffness, the robust engineering method is considered for identifying the external conditions that generate different dynamic behavior results for the variation of structural stiffness. This study allows us to identify maneuvers or situations in which considerations of structural flexibility in multibody model, or even in a real physical condition, are relevant and can affect the safety, ride and handling of the vehicle.
90

Rigidez quase-simétrica para mapas multicríticos do círculo / Quasisymmetric rigidity of multicritical circle maps

Jacinto, Gabriela Alexandra Estevez 10 March 2017 (has links)
No presente trabalho consideramos homeomorfismos do círculo sem pontos periódicos e com o mesmo número finito de pontos críticos todos de tipo non-flat. Provamos que se existe uma conjugação topológica entre dois destes mapas que leva ponto crítico em ponto crítico, sem necessidade de preservar criticalidades, então dita conjugação é uma transformação quase-simétrica com distorção quase-simétrica local uniformemente limitada. Estes resultados são válidos para qualquer número de rotação irracional e são independentes da natureza das criticalidades dos pontos críticos, de modo que nossos resultados são válidos para toda criticalidade real. / In this work we consider circle homeomorphisms without periodic points and with finite number of critical points all of them being non-flat. We prove that if there exists a topological conjugacy between two of those maps which sends critical point into critical point, which not necessarily preserve criticalities, then this conjugacy is a quasi-symmetric map with quasi-symmetric distortion universally bounded. All these results are valid for any irrational rotation number and are independent of the nature of the criticalities, therefore our results are valid for all real criticalities.

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