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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.
1

Sensorless position estimation in asymmetric induction machines

Staines, Cyril Spiteri January 1998 (has links)
No description available.
2

Salience asymmetries in the Implicit Association Test

Chang, Betty, Psychology, Faculty of Science, UNSW January 2008 (has links)
The Implicit Association Test (IAT) is the most popular indirect measure of attitudes in social psychology. It has been suggested that salience asymmetries are a non-associative contaminant of the IAT that threatens the accurate assessment of attitudes. Salience asymmetries in the IAT are claimed to correspond with visual search asymmetries, and differences in target familiarity. In this thesis, I propose that processing fluency is the common mechanism underlying both visual search asymmetries and familiarity. Several experiments were conducted to determine whether visual search asymmetries, familiarity, or processing fluency most reliably corresponds with salience asymmetry effects in the IAT. The first series of experiments revealed that processing fluency is a better predictor of salience asymmetry effects in the IAT than is visual search asymmetry (Chapter 2). In Chapter 3, a novel method was developed to distinguish between the effects of valence and salience in the IAT. Using this method, I demonstrated that the effects of salience in the IAT are consistent with a fluency account of salience asymmetries. Familiarity was also shown to produce salience asymmetry effects in the IAT (Chapter 4), which is also consistent with the fluency account. When fluency and familiarity were set against each other in Chapter 5, it was processing fluency, rather than familiarity, that predicted salience asymmetry effects in the IAT. Although processing fluency is a good predictor of salience asymmetries, the results of Chapter 6 reveal that the fluency account cannot explain all examples of salience asymmetries in the IAT. The data presented here are consistent with the view that the more fluently processed target category is compatible with the pleasant attributes on the grounds of salience asymmetries. The current experiments suggest that when there are valence differences between the target categories, salience asymmetries can potentially distort IAT effects. When the positive target category is more salient, salience asymmetries appear to increase IAT effects. In contrast, when the negative target category is more salient, salience asymmetries appear to decrease IAT effects. However, further evidence is required to determine how the effects of salience and valence combine in the IAT.
3

A treadmill/force plate device for real-time gait symmetry assessment and feedback in normal and amputee subjects

Dingwell, Jonathan Bates January 1994 (has links)
No description available.
4

A Whole that may be Greater than the Sum of its Parts: A Balanced Mind from Biased Processes

Hasinski, Adam E. 22 October 2010 (has links)
No description available.
5

Chápanie informačných asymetrií pomocou dizajnu mechanizmov / Understanding Information Asymmetries through Mechanism Design

Albert, Branislav January 2014 (has links)
This thesis serves as an introduction and overview of the broad and closely related fields of mechanism design, contract theory, and information economics. Each chapter is intended to provide a self-contained guide to the particular area of application -- examples include adverse selection, moral hazard, and auctions. The reader should benefit from the thesis in two ways: by understanding the general notions of the revelation principle, incentive compatibility, and individual rationality from the mechanism design theory as well as by examining the particular information asymmetry models in the individual areas. Powered by TCPDF (www.tcpdf.org)
6

Assimetrias posturais, demandas musculares e gasto energético em jovens e idosos na postura ereta / Postural asymmetry, muscular demands and energetic cost in young and elderly individuals during upright standing

Rico, Janina Manzieri Prado 05 March 2015 (has links)
A permanência em pé por um determinado período de tempo exige que os indivíduos produzam periodicamente mudanças posturais, que podem favorecer a adoção de posturas mais assimétricas. Diante da deterioração do sistema de controle postural, é possível que idosos tenham uma dificuldade em permanecerem assimétricos em atividades do cotidiano. Em adição, variações no padrão de ativação muscular podem aumentar o gasto energético e levar os idosos a fadiga, o que resulta em sérias consequências como aumento no risco de quedas. Acredita-se que mudanças posturais durante a postura relaxada ocorram distintamente em adultos jovens e idosos, podem exigir esforços musculares variados e assim influenciar no gasto energético. O presente estudo investigou as assimetrias posturais, ativações musculares e gasto energético em adultos jovens e idosos saudáveis na postura ereta. Cinquenta e três jovens e 16 idosos permaneceram em diferentes posturas enquanto registrou-se as assimetrias na distribuição de peso ao longo do tempo (ADPm). Todos os idosos e 12 jovens submeteram-se ao registro eletromiográfico para análise dos padrões de ativação muscular de músculos da coxa e perna, e 7 indivíduos de cada grupo foram submetidos ao registro de gases para análise do gasto energético, consumo de oxigênio (VO2), quociente respiratório (R) e medida de frequência cardíaca. Os idosos apresentaram dificuldade na transferência de peso em posturas mais assimétricas e ambos os grupos apresentaram ligeira assimetria na postura ereta quieta (em torno de 5±4% de ADPm). Na postura relaxada a maior parte do tempo os indivíduos permaneceram em faixas de pequenas assimetrias, seguido de um tempo menor em posturas significativamente assimétricas. Em geral, as ativações musculares foram maiores em idosos, porém eles foram capazes de recrutar músculos de modo similar aos jovens. O aumento da atividade do músculo gastrocnêmio foi proporcional às posturas mais assimétricas em ambos os grupos. O gasto energético não sofreu grandes variações em condições de simetria ou assimetria posturais em jovens e idosos, porém parece que o aumento do gasto energético nos idosos está relacionado com o aumento da atividade muscular, o que poderia justificar a adoção de posturas menos assimétricas por parte desses indivíduos. Os resultados do presente estudo levantam a questão da possibilidade de haver maior gasto energético, principalmente em idosos, e abre novas possibilidades para que futuros estudos possam compreender a demanda metabólica envolvida na manutenção da postura ereta / To remain standing for a certain period of time we periodically produce postural changes, which may favouring the adoption of more asymmetric postures. In face of the postural control system deterioration, it is possible that older people find it difficult to adopt more asymmetrical postures during daily life activities. In addition, changes in muscle activation pattern may increase energy cost to stand in asymmetric posture, which would lead to muscle fatigue and as consequence increase in fall risk in this population. Thus, postural changes during relaxed postures and the muscular demand necessary to perform such changes may differ among young and older adults, resulting in different energy cost. The present study investigated body weight asymmetries, muscle activations and energy cost in healthy young and elderly adults during sanding tasks with different constrains. Fifty-three young and sixteen elderly subjects remained at different positions while we recorded the body weight asymmetry over time (ADPm). All the elderly participants and twelve young adults undergone to electromyographic record of the thigh and leg muscles, and 7 subjects in each group to gas record in order to quantify the energy cost, oxygen consumption (VO2) and respiratory quotient (R) and registered heart rate. During quiet standing task, both age groups showed a slight and similar WDA (mean values around 5%). However, the elderly had difficulty in maintaining more asymmetric postures - they were less asymmetrical than young in tasks that required great WDA. In the relaxed position, most of the time the subjects remained in small asymmetry ranges, followed by a shorter period in more asymmetric postures. In general, muscle activation level was higher in the elderly, but they were able to recruit muscle in a similar way to young subjects. In addition, gastrocnemius activity increased proportionally to body weight support in both age groups - it was greater in the supportive limb in the most asymmetric postures. Although in this study the energy cost was not significantly affected by the asymmetry in body weight distribution in young and old individuals, it seems that the increased energy cost in the elderly is associated with an increase in muscle activity, which might explain the adoption of less asymmetric postures by these individuals. The results of this study raise the question of the possibility of higher energy expenditure in more asymmetric postures, especially in the elderly, and opens new possibilities for future studies to understand the metabolic demands during upright standing
7

Investigações sobre o controle motor e postural nas assimetrias em membros inferiores / Investigations about motor and postural control during asymmetries in lower limbs

Marchetti, Paulo Henrique 15 December 2009 (has links)
Durante diferentes atividades cotidianas ou esportivas o ser humano é submetido a desafios unilaterais que podem estar relacionados à performance de uma tarefa específica ou a própria manutenção de sua postura. Portanto, é natural o desenvolvimento motor de um membro em relação ao outro para tarefas específicas, desde que estas sejam repetidas de forma não simétrica. Desta forma, pode-se supor que sujeitos que possuam maiores estresses físicos unilaterais apresentem maior probabilidade em desenvolver assimetrias funcionais e morfológicas. O presente trabalho apresenta três diferentes experimentos visando investigar as assimetrias funcionais e morfológicas relacionadas ao controle de movimento para tarefas dinâmicas e estáticas em diferentes condições e grupos. O primeiro experimento visou investigar as diferenças, entre os membros inferiores, no controle de movimento entre sedentários e atletas, utilizando para isto a postura ereta quieta e o salto com contra-movimento nas condições bipedais e unipedais. O segundo experimento visou investigar o efeito da fadiga neuromuscular unilateral e bilateral no controle de movimento, entre membros, durante o salto com contra-movimento e a postura ereta quieta bipedal. O terceiro experimento objetivou investigar o efeito prolongado da temporada esportiva no controle de movimento, entre membros, de atletas, utilizando o salto com contra-movimento e a postura ereta quieta nas condições unipedal e bipedal. Inicialmente, o presente trabalho concluiu que não parece existir relação entre as diferenças antropométricas e funcionais. Indivíduos sedentários e atletas possuem diferenças entre os membros inferiores, entretanto supõe-se que os mecanismos relacionados à tais fenômenos não sejam os mesmos, como no caso dos sedentários, onde as assimetrias poderiam estar relacionadas ao pobre controle de força, sinergismo e padrão de coordenação.. Analisando as diferenças entre sedentários e atletas foram observadas semelhanças em relação ao nível de assimetria para algumas variáveis analisadas. Deve-se considerar que os atletas analisados estavam no início da temporada esportiva, e possivelmente sem grande influência dos efeitos do treinamento prolongado. Para testar a hipótese do efeito prolongado, o terceiro experimento foi realizado e observou-se que a temporada esportiva não afetou todas as variáveis relacionadas ao controle de movimento estático e dinâmico em atletas e os maiores efeitos foram verificados durante as tarefas bipedais. Além disto, a fadiga neuromuscular também influenciou o controle de movimento em sedentários, produzindo ajustes compensatórios em algumas variáveis, principalmente nos ângulos articulares. Entretanto, as assimetrias previamente observadas não parecem serem alteradas durante as diferentes condições de fadiga neuromuscular. Para a tarefa dinâmica bipedal, observou-se que para todas as variáveis analisadas (ângulos articulares, parâmetros de desempenho e atividade muscular) apresentaram assimetrias. Curiosamente, se observa tendência à maior ativação do membro contra-lateral em função do membro fatigado. Portanto, o presente estudo ressalta o efeito do nível de condicionamento, o efeito da fadiga e do treinamento prolongado no controle de movimento dos membros inferiores em tarefas com diferentes demandas motoras bipedais e unipedais / The human body is exposed to different unilateral challenges during different daily and sportive tasks. These challenges may either be related to specific-task performance or posture maintenance. Thus, it is natural the increase of motor control in one limb related to another during specific tasks and movements. It can be assumed that individuals exposed to higher physical unilateral stress show greater probability to develop functional and morphological asymmetries. The present study shows three different experiments in order to investigate the functional and morphological asymmetries related to the motor control for dynamic and static tasks in different conditions and groups. The first experiment aimed to investigate the differences between the lower limbs, related to the motor control between sedentary and athletes during two tasks: quiet stance and countermovement jump in bi- and unipedal conditions. The second experiment aimed to investigate the effect of neuromuscular fatigue on uni- and bilateral tasks related to the motor control between lower limbs during both double-leg tasks: countermovement jump and quiet stance. The third experiment aimed to investigate the effect of prolonged sportive season in motor control, between lower limbs, during two tasks: quiet stance and countermovement jump in bi- and unipedal conditions. We concluded that there was no correlation between the anthropometric and functional asymmetries. Both sedentary and athlete groups had differences between the lower limbs in several variables, however it is assumed that the mechanisms related to such phenomena are not the same. There were similarities between sedentary and athlete groups related to the level of asymmetry for some variables. We must consider that the athletes were analyzed at the beginning of the sportive season, without the training influence. To verify the prolonged effect hypothesis, the third experiment was conducted and it was observed that the sportive season did not affect all the variables related to the motor control and the greatest effects were observed during the bipedal tasks. In addition to that, the neuromuscular fatigue influenced the control of movement in the sedentary group, showing compensatory adjustments in some variables, especially in the maximal joint angles. However, we observed that the asymmetries did not change during different neuromuscular fatigue conditions. During the bipedal dynamic task it was observed asymmetries in all variables (joint angles, performance parameters and muscle activity). Interestingly, it was also observed the trend to higher activation of the contra-lateral lower limb during the fatigued limb. So, this study highlights the effect of the conditioning levels, the neuromuscular fatigue effect and the prolonged training to the motor control of the lower limbs in different tasks and conditions
8

Asymmetric monetary transmission?: evidence from CEE region

Šarić, Amela January 2012 (has links)
This thesis investigates monetary transmission asymmetries in CEE region. The first part addresses the role of credit growth in monetary transmission in the Czech Republic. Employing Logistic Smooth Transition Vector Autoregression model over the 1998:M1-2012:M3 period, we find that high credit growth dampens the effectiveness of monetary policy. No asymmetries in relative effects of contractionary and expansionary monetary policy shocks have been documented. In the second part, we apply the variation of Panel VAR to examine the role of financial structure in monetary transmission. The analysis is conducted on a sample of eight CEE states, encompassing the 1999:Q1-2009:Q4 period. Higher credit dependence is found to enhance the interest rate pass-through. However, cross-country asymmetries vanish when the credit dependence is interacted with the measure of banking sector competition. The ultimate role of financial structure in output and price fluctuations is indeterminable.
9

Essays in Applied Macroeconomics: Asymmetric Price Adjustment, Exchange Rate and Treatment Effect

Gu, Jingping 15 May 2009 (has links)
This dissertation consists of three essays. Chapter II examines the possible asymmetric response of gasoline prices to crude oil price changes using an error correction model with GARCH errors. Recent papers have looked at this issue. Some of these papers estimate a form of error correction model, but none of them accounts for autoregressive heteroskedasticity in estimation and testing for asymmetry and none of them takes the response of crude oil price into consideration. We find that time-varying volatility of gasoline price disturbances is an important feature of the data, and when we allow for asymmetric GARCH errors and investigate the system wide impulse response function, we find evidence of asymmetric adjustment to crude oil price changes in weekly retail gasoline prices Chapter III discusses the relationship between fiscal deficit and exchange rate. Economic theory predicts that fiscal deficits can significantly affect real exchange rate movements, but existing empirical evidence reports only a weak impact of fiscal deficits on exchange rates. Based on US dollar-based real exchange rates in G5 countries and a flexible varying coefficient model, we show that the previously documented weak relationship between fiscal deficits and exchange rates may be the result of additive specifications, and that the relationship is stronger if we allow fiscal deficits to impact real exchange rates non-additively as well as nonlinearly. We find that the speed of exchange rate adjustment toward equilibrium depends on the state of the fiscal deficit; a fiscal contraction in the US can lead to less persistence in the deviation of exchange rates from fundamentals, and faster mean reversion to the equilibrium. Chapter IV proposes a kernel method to deal with the nonparametric regression model with only discrete covariates as regressors. This new approach is based on recently developed least squares cross-validation kernel smoothing method. It can not only automatically smooth the irrelevant variables out of the nonparametric regression model, but also avoid the problem of loss of efficiency related to the traditional nonparametric frequency-based method and the problem of misspecification based on parametric model.
10

ASYMMETRIC INFORMATION IN EMERGING MARKETS: LESSONS FROM CHINA

DING, Xiaoya 25 March 2011 (has links)
Asymmetric information has crucial implications for various market participants in financial markets, including investors (local and foreign), firms, and governments. The information asymmetry problem is especially severe in emerging markets. My dissertation attempts to address a few information-related questions that interest both academicians and practitioners. The first study adds some new evidence to the on-going debate of whether local or foreign investors are better informed. I offer a new perspective to the issue by examining two market segments within one country but separated by the relevance of local knowledge measured by state ownership. I find that state ownership has a dramatic asymmetric effect on local and foreign institutional investors in China’s stock market. Local (foreign) institutional investors have an informational advantage in state-owned enterprises (SOEs), while foreign institutional investors have an informational advantage in non-state-owned enterprises (non-SOEs). Moreover, the informational advantage of local institutional investors is less evident in SOEs with high board independence and better audit quality. Building on these results, the second study further uses local and foreign institutional ownership as a measure of private information and examines whether firm-specific return volatility proxies for price informativeness. I find firm-specific return volatility is positively related to private information. Therefore the results support the notion that firm-specific return volatility measures the rate of private information impounded into stock prices. My research contributes to the literature in at least four important ways. My findings reconcile the two opposing views on local and foreign investors in the literature and suggest that the informational advantages of local and foreign investors vary with the relevance of local knowledge. Examining only the whole market in past research masks important variation in the relative advantages of local and foreign investors in market segments within a country. My study also suggests that taking into account firm-level characteristics, especially corporate governance measures, can enhance our understanding of the behavior of institutional investors. Additionally I provide some of the first evidence to show that local political institutions can create barriers faced by international investors. Finally, my research confirms the merit of firm-specific return volatility as a measure of price informativeness. Together, these studies provide new insights into research on asymmetric information in emerging markets and have important implications for local and foreign investors, firms, and governments. / Thesis (Ph.D, Management) -- Queen's University, 2011-03-24 19:35:47.788

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