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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.
211

A numerical procedure for computing errors in the measurement of pulse time-of-arrival and pulse-width

Haden, Lonnie A. January 2010 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
212

A prerrogativa do inusitado: o estatuto da ação em Bergson

Galvão, Jadir Mauro 07 October 2011 (has links)
Made available in DSpace on 2016-04-27T17:26:58Z (GMT). No. of bitstreams: 1 Jadir Mauro Galvao.pdf: 497456 bytes, checksum: 9c9717516eca0c9cf101545a2a25d668 (MD5) Previous issue date: 2011-10-07 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / When getting deeper in the general thought of the meaning of Time, Bergson not only finds out a particular way in which our Intelligence functions but also discovers that this functioning interferes heavily in our view of the world, both our actions and our daily decisions. It happens as a narrowing of our range of vision which imposes a limit to our actions, as well as to our expectations. We depict the world in our conscience, but only that specific part which is coherent to our concepts, and also only what we can translate through language. From that on, our actions will be always based on the same concepts already solidified in the past, and will always be described by language. This will only bring us repetitions. Choosing Intuition as the way to keep contact with reality, Bergson searches for removing the obstacles which Intelligence has introduced only for the sake of calculations, measurements and predictions, which have become a filter to reality. When we remove the symbolic intervention, we will have a more complete view of the world that surrounds us, and also a truly open field for our actions. If, for Bergson, the concept of Duration is a more trustworthy way to translate reality than the concept of Time, it is not less true for him that the past consubstantiates the present in an inseparable interpenetration which turns into a unique and singular present. Also, more than just another distinct element in the conceptual web, the future is not there to be revealed, but to be started, to be created, filled with something unexpected, not only as some clay modeled by our past experiences, but as a blank screen ready to receive creative strokes by us, the artists / Ao escavar por debaixo da idéia que em geral temos sobre o tempo, Bergson encontra o peculiar modo de funcionamento de nossa inteligência, bem como descobre que esse funcionamento exerce profunda interferência sobre nossa visão do mundo. Seja em termos de nossas ações ou nossas decisões cotidianas. Ocorre como um estreitamento de nosso ângulo de visão que impõe uma redução de nosso campo de ação, tanto quanto um encurtamento dos nossos horizontes. Representamos o mundo em nossa consciência, mas apenas o tanto de mundo que faz coerência com nossos conceitos, bem como só o que conseguimos traduzir pela linguagem. A partir disto nossas ações terão por base sempre os mesmos conceitos já firmados no passado, como também sempre poderão ser descritas pela linguagem. Não teremos com isso mais do que repetições. Ao eleger a intuição como modo de contato com a realidade, Bergson busca a remoção dos obstáculos que a inteligência introduziu apenas por comodidade para suas operações de cálculo, medição e previsão e que se transformaram em um filtro da realidade. Removidas as mediações simbólicas teremos diante de nos uma visão mais completa do mundo que nos cerca, tanto quanto um campo francamente aberto para nossas ações. Se para Bergson a idéia de duração traduz de modo mais fiel a realidade do que o conceito de tempo, não é menos verdade para ele que o passado se consubstancia com o presente numa interpenetração indissociável que culmina num presente único e singular. Assim também, mais do que apenas outro elemento distinto da trama conceitual, o futuro não está ai para ser descoberto, mas sim para ser inaugurado, para ser criado, preenchido com algo inusitado. Não apenas com a massa já moldada pelas nossas experiências passadas, mas como uma tela em branco, pronta para receber os traços criadores dos artistas que somos todos nós
213

The role of sensory history and stimulus context in human time perception : adaptive and integrative distortions of perceived duration

Fulcher, Corinne January 2017 (has links)
This thesis documents a series of experiments designed to investigate the mechanisms subserving sub-second duration processing in humans. Firstly, duration aftereffects were generated by adapting to consistent duration information. If duration aftereffects represent encoding by neurons selective for both stimulus duration and non-temporal stimulus features, adapt-test changes in these features should prevent duration aftereffect generation. Stimulus characteristics were chosen which selectively target differing stages of the visual processing hierarchy. The duration aftereffect showed robust interocular transfer and could be generated using a stimulus whose duration was defined by stimuli invisible to monocular mechanisms, ruling out a pre-cortical locus. The aftereffects transferred across luminance-defined visual orientation and facial identity. Conversely, the duration encoding mechanism was selective for changes in the contrast-defined envelope size of a Gabor and showed broad spatial selectivity which scaled proportionally with adapting stimulus size. These findings are consistent with a second stage visual spatial mechanism that pools input across proportionally smaller, spatially abutting filters. A final series of experiments investigated the pattern of interaction between concurrently presented cross-modal durations. When duration discrepancies were small, multisensory judgements were biased towards the modality with higher precision. However, when duration discrepancies were large, perceived duration was compressed by both longer and shorter durations from the opposite modality, irrespective of unimodal temporal reliability. Taken together, these experiments provide support for a duration encoding mechanism that is tied to mid-level visual spatial processing. Following this localised encoding, supramodal mechanisms then dictate the combination of duration information across the senses.
214

Rytmické rozdíly mezi velškou angličtinou a britským standardem / Rhythmic differences between Welsh English and the British standard

Hejná, Michaela January 2012 (has links)
The present thesis deals with rhythmic differences between Welsh English and the British Standard. It focuses on the varieties spoken in Cardiff and Aberystwyth in particular. The first part of the theoretical chapter summarises the approaches towards rhythm from the physiological, acoustic, perceptual, and phonological perspectives. The second part provides a basic description of the British Standard, Welsh, and Welsh English. It concerns itself with the existing information related to the subject matter especially as regards Welsh varieties of English. The last, third part, serves as an overview of the most common approaches towards the search of the acoustic correlates of rhythm (%V, ∆C, ∆V, PVI, varco, RR, YARD). The following chapters of the thesis present a material based study of the data obtained for the purposes of the thesis. The segmentation was carried out according to the principles proposed by Machač and Skarnitzl 2009. Rhythm was measured for four respondents for each selected location of Wales. The age span was 35-39 years for the group from Cardiff and 29-39 for that from Aberystwyth. The values measured were compared with the research of Volín and Pollák from 2009, which, among other things, provided the results of the rhythmic values for %V and ∆C for the British Standard on the...
215

Níveis de atividade física nas aulas de Educação Física

Moreira, Rodrigo Baptista January 2014 (has links)
A elaboração deste estudo baseia-se em analisar, a partir de uma proposta de educação física escolar com foco no desenvolvimento de atividades esportivas, os níveis de intensidade da atividade física (AF) dos escolares nas aulas de educação física. A pesquisa se caracteriza como um estudo de caso institucional. A amostra do tipo aleatória estratificada constante foi composta de 206 crianças, sendo avaliados 112 meninos e 94 meninas, observados durante as aulas conforme os grupos de idade e sexo. Foram avaliados 72 aulas sendo realizadas 386 avaliações (não indivíduos) por meio de GPS da marca GARMIN, modelo 310XT, com frequencímetro. A porcentagem de tempo em que a criança realizava AF nas diferentes faixas de frequência cardíaca foi estabelecida conforme a proposta de pontos de corte sugerido por Armstrong (1998). Para a apresentação dos resultados utilizamos estatística descritiva identificando a proporção de tempo em AF nos diferentes níveis de intensidade, tempo de deslocamento ativo, distância percorrida e gasto energético. Realizamos um estudo exploratório com o objetivo de avaliar os pressupostos essenciais da análise paramétrica. Após a inspeção, utilizamos médias e desvio-padrão para a descrição dos dados. Quanto ao estudo comparativo entre os sexos nas variáveis utilizamos o teste “t” de student para amostras independentes. Para a avaliação das diferenças entre as categorias de idades, nos dois sexos, recorremos a ANOVA seguida de post hoc de Bonferroni. Os resultados indicaram comportamentos distintos entre rapazes e moças quanto ao nível de intensidade da prática de AF realizada nas aulas de educação física. Observamos que a proporção média de tempo dos rapazes engajados na realização de AF vigorosa aumenta ao longo das idades, enquanto as moças apresentam uma redução da prática de AF nesta intensidade ao longo do tempo. Quando realizamos o somatório da prática de AF moderada e vigorosa (AFMV), observamos que a proporção média é semelhante entre rapazes e moças. Cerca de 2/3 da aula de educação física é realizada nestas faixas de intensidade cumprindo com as recomendações de pelo menos 50% das aulas nesta faixa de intensidade. As moças apresentam valores próximos dos rapazes para a prática de AFMV, mas realizam suas atividades de forma predominantemente moderada e reduzem o tempo de prática de AFMV ao longo do tempo. Além disso, os resultados indicaram que a prática de algumas modalidades esportivas exigem mais do que outras. O voleibol foi a modalidade esportiva que menos exigiu dos escolares quanto ao nível de AF vigorosa, ao passo que as exigências maiores foram encontradas nas modalidades ciclismo, futebol e futsal. Quanto ao tempo semanal engajado em práticas de AFMV, somente com as aulas de educação física os rapazes cumprem com cerca de 2/3 da carga horária semanal recomendada (>300 minutos por semana) e, as moças, com valores inferiores ao apresentado pelos rapazes, cumprem com cerca de 50% da carga horária sugerida. Concluímos que a proposta para a educação física escolar apresenta níveis de intensidade e duração satisfatórios quanto ao necessário para a promoção da saúde, principalmente quando do somatório do tempo de AF realizada durante a semana. / The formulation of this study is based on analyzing from a propose physical education focusing on the development of atletics activities, the intensity levels of physical activity (PA) on the Student is in physical education classes. The research is characterized as an institucional case sttudy. The type stratified random sample of constant 206 was compused of children being evaluated 112 boys and 94 girls, during the lessons, according to age groups and gender. Were evaluated in 72 classes 386 reviews being performed (not indivuduals) via GPA GARMIN, model 3010 XT, with frequency conter. The percentage of time that the child performed PA in different ranges of heart rate was established conform the proposed cut off points suggested by Armestrong (1998). For the apresentation results, we used descriptive statistics to identify the proportion of time in PA in diferent intensity, activy commung time, distance and energy expenditure. Conducted an exploratory study to evaluate the essencial assumptions of parametric anlysis. After the inspection, we use mean and standard deviation for the data description. Regarding the study comparing the sexes in the variables, use the “t” Student test for independente samples. For the evoluation of diferences between age categories in both sexes, we used ANOVA followed by Pos-Hoc Bonferroni. The results indicate diferente behaviors between boys and girls regarding level intensity of PA. Performed in pratice of PA held in physical education classes. We observed that the average proportion of time the boys engaged in perfoming vigorous PA, increases throughout the ages, while girls showed a reduction in the pratice of this PA intensity over time. When we perform the sum of practing moderate na vigorou PA (PAMV), we observed that the average ratio is similar between boys and girls. About two-thirds of the physical education class is held in these intensity ranges complyng with the recommendations of at least 50% of classes in this intensity range. Girls showed the boys next values for practice PAMV but perform their activities predominantly moderate and shorten time to practicing PAMV over time. Furthermore, the results indicate that the practice of some sports require more than others. The volleyball was the sport that demanded less of the students regarding their level of vigorous PA, where as the highest demands found in rules:cycling, soccer and futsal. As for the weekly time engaged in practies PAMV, amounts only with the physical education classes the boys weet with about two thirds of weekly recommended (>300 minutes per week) and the girls, twith lower values than shown by the boys, meet about 50% of the worklord suggested. We conclude that the proposal for school physical education has levels of intensity and duration as to be satisfactory for health promotion, particularly when the sum of the time of PA perfomed during the week level.
216

Association Between Sleep Duration During Adolescence and Violent Behavior Among Young Adults in the United States

Subedi, Pooja, Alamian, Arsham, Brooks, Billy, Alamian, Ali, Zheng, Shimin 04 November 2017 (has links)
Youth violence is a public health threat in the United States. Inadequate sleep is identified as a risk factor, however, the majority of previous studies were cross-sectional and focused only on adolescents. This study aimed to investigate the association between average hours of sleep during adolescence and violent behavior among youths. Individuals who participated in both Waves II (1996) and III (2000-2001) of National Longitudinal Study of Adolescent and Adult Health (n=3,557) were included. A composite variable on violent behavior was created using three different questions on fighting or using a weapon. Age, gender, ethnicity, violent behavior during adolescence, depressive symptoms, impulsivity, and current sleep hours were considered as covariates. Negative binomial regressions were conducted using SAS 9.4. The mean age of the participants was 15.85 years (SD=1.62) and 21.29 years (SD=1.60) in waves II and III, respectively. The majority of the participants were female (54.15%) and non-Hispanics (88.93%). Average hours of sleep during adolescence was not significantly associated with violent behavior during young adulthood (p=0.75). In the final model, gender (beta=1.65, p<0.001), age (beta=-0.1267, p<0.001), history of violent behavior (wave II) (beta=0.3158, p<0.0001), current average hours of sleep (wave III) (beta=-0.073, p=0.044), depressive symptoms (beta=0.0834, p <0.0001), and impulsivity (beta=0.1379, p<0.0001) were significantly associated with violent behavior in early adulthood. Reduced number of sleep hours during early adulthood, unlike during adolescence, increased the likelihood of getting involved in violent activities during early adulthood. This information is useful to promote healthy behavior among individuals in all phases of their life.
217

The Effects of Reinforcement Magnitude and Temporal Contingencies on Pre-Ratio Pause Duration

Bonem, Marilyn K. 01 May 1988 (has links)
The present study was conducted to determine whether conjugate magnitude and temporal contingencies were effective in increasing the pre-ratio pause (PRP) duration and to determine the controlling variables that govern such contingencies. It has been reported in the literature that magnitude of reinforcement, if presented contingently, is effective in controlling performance and that inserting intervals of blackout (BO), during which responding does not lead to reinforcement, virtually always leads to control of responding, even though it has not been presented contingently. The conjugate schedules experimentally arranged reinforcement such that the longer the PRP, the longer was the duration of access to reinforcement and/or the shorter was the BO, located either after reinforcement or after the response. The results of this study demonstrated that the major independent variable which controlled mean PRP duration on the various conjugate reinforcement schedules studied was the delay between the response and reinforcement. The duration of the PRP was not reliably controlled by a contingency which equated PRP duration with reinforcement duration, nor by a contingency which, through imposition of a delay to trial onset, held the local delay to reinforcement constant. Additionally, cycle-to-cycle variation in reinforcement magnitude, whether presented contingently or noncontingently on PRP duration, had no reliable effect on PRP duration when compared to FR 1. The primary effect of variation in the duration of reinforcement was to reduce the variability, not the duration, of the PRP. The results of the study are briefly discussed in terms of a number of theories. These include: the maximization account (Logan, 1960); the matching law (Herrnstein, 1970); Harzem and Harzem's (1981) theory describing the unconditioned inhibitory stimulus function of reinforcement; behavioral contrast (Reynolds, 1961); and Dews' (1981) account of the importance of a response-reinforcer contiguity relation.
218

WHAT INDUCES FEMALE KICKING IN <em>CALLOSOBRUCHUS MACULATUS</em>? DISENTANGLING THE EFFECTS OF MALE TRAITS ON FEMALE MATING DECISIONS

Licht, William I. 01 January 2017 (has links)
Sexual conflict over mating duration drives the evolution of male and female adaptations that facilitate the manipulation of mating interactions in their favor. This conflict drives the evolution of traits that improve the fitness of the focal sex despite inflicting costs on mates. However, males can express multiple traits that increase and decrease female fitness simultaneously. When the effects of male traits on female fitness increase or decrease with duration of exposure, females traits that influence mating duration are selected upon. Females of Callosobruchus maculatus, a bruchid bean beetle, kick mates to forcefully end copulation. Although both negative effects of male genital spines and positive of effects ejaculatory materials on female fitness have been documented, it is not yet clear how these male traits interact to influence the timing of female kicking. In this study, we observed the effect of male genital spine size, ejaculate size and mating history, and manipulated mating duration to disentangle the effects of male traits on the timing of female kicking behavior. We found that male mating history and mate body size dimorphism predicted the timing and duration of female kicking, but that male ejaculate size and spine length did not predict female kicking timing.
219

Federal Funds Target Rate Surprise and Equity Duration

Tee, Kienpin 05 1900 (has links)
In this paper I use an equity duration framework to develop and empirically test the hypothesis that returns on growth stock portfolios react more strongly to Federal Funds target rate change announcements, as compared to value stock portfolios. When I decompose the Federal Funds rate change, I find that portfolio returns are only sensitive to rate shocks, as opposed to the predictable component of rate change. Since growth stocks are expected to have higher duration than value stocks, I further explore the well documented polarity between value and growth stocks, by examining the interest rate sensitivities of portfolios that diverge along four fundamental-to-prices ratios: dividend yield, book-to-market value, earnings-to-price and cashflows-to-price. In each case, I find that price reactions are more pronounced for portfolios with high growth characteristics. I also document that portfolio returns react asymmetrically to positive and negative target rate surprises, and that this reaction is conditional on the state of business cycles - periods of economic expansions and recessions. To improve the robustness of my results, several statistical applications have been applied. First, I include Newey-west estimators to examine significant levels of regression estimates. Second, I check if there is any contemporaneous correlation across target rate shocks by applying ARIMA tests, and to overcome the problem resulted from serial correlation of target rate shocks, I substitute white noise residuals from the regressions on the rate shocks for target rate shocks to be new exogenous variables.
220

Detecting Change in Rainstorm Properties from 1977-2016 and Associated Future Flood Risks in Portland, Oregon

Cooley, Alexis Kirsten 07 September 2017 (has links)
In response to increased greenhouse gases and global temperatures, changes to the hydrologic cycle are projected to occur and new precipitation characteristics are expected to emerge. The study of these characteristics is facilitated by common indices to measure precipitation and temperature developed by the Expert Team on Climate Change Detection and Indices (ETCCDI). These indices can be used to describe the likely consequences of climate change such as increased daily precipitation intensity (SDII) and heavier rainfall events (R95p). This study calculates a subset of these indices from observed and modelled precipitation data in Portland, Oregon. Five rainfall gages from a high resolution rain gage network and projections from three downscaled global climate models including CanESM2, CESM1, CNRM-CM5 are used to calculate precipitation indices. Mann-Kendall's tau is used to detect monotonic trends in indices. The observational record is compared with models for the historic period (1977-2005) and these past trends are compared with projected future trends (2006-2100). The influence of study unit on trend detection is analyzed by computing trends at the annual and monthly scale. Study unit is shown to be important for trend detection. When the annual study unit is used, projected future trends towards increased precipitation intensity and event volumes are not observed in the historic data. However, when analyzed with a monthly study unit, trends towards increased precipitation intensity and event volumes are observed in the historic data. These trends are shown to be important for Portland area flooding, as precipitation indices are shown to significantly correlate with 40 maximum peak flow events that occurred during the period of study.

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