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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.
101

Intensity Auto- and Cross-Correlations and Other Properties of a <sup>85</sup>Rb Atom Coupled to a Driven, Damped Two-Mode Optical Cavity

Hemphill, Patrick A. 24 July 2009 (has links)
No description available.
102

Two-Particle Correlations in Heavy-Light Ion Collisions

Wertepny, Douglas E. January 2016 (has links)
No description available.
103

Selective correlations in finite quantum systems and the Desargues property

Lei, Ci, Vourdas, Apostolos 26 March 2018 (has links)
Yes / The Desargues property is well known in the context of projective geometry. An analogous property is presented in the context of both classical and Quantum Physics. In a classical context, the Desargues property implies that two logical circuits with the same input, show in their outputs selective correlations. In general their outputs are uncorrelated, but if the output of one has a particular value, then the output of the other has another particular value. In a quantum context, the Desargues property implies that two experiments each of which involves two successive projective measurements, have selective correlations. For a particular set of projectors, if in one experiment the second measurement does not change the output of the rst measurement, then the same is true in the other experiment.
104

Enhancing Structure-Function Correlations in Glaucoma with Customised Spatial Mapping

Ganeshrao, S.B., Turpin, A., Denniss, Jonathan, McKendrick, A.M. 08 1900 (has links)
No / Purpose To determine whether the structure–function relationship in glaucoma can be strengthened by using more precise structural and functional measurements combined with individualized structure–function maps and custom sector selection on the optic nerve head (ONH). Design Cross-sectional study. Participants One eye of each of 23 participants with glaucoma. Methods Participants were tested twice. Visual fields were collected on a high-resolution 3° × 3° grid (164 locations) using a Zippy Estimation by Sequential Testing test procedure with uniform prior probability to improve the accuracy and precision of scotoma characterization relative to standard methods. Retinal nerve fiber layer (RNFL) thickness was measured using spectral-domain optical coherence tomography (OCT; 4 scans, 2 per visit) with manual removal of blood vessels. Individualized maps, based on biometric data, were used. To customize the areas of the ONH and visual field to correlate, we chose a 30° sector centered on the largest defect shown by OCT and chose visual field locations using the individualized maps. Baseline structure–function correlations were calculated between 24-2 locations (n = 52) of the first tested visual field and RNFL thickness from 1 OCT scan, using the sectors of the Garway-Heath map. We added additional data (averaged visual field and OCT, additional 106 visual field locations and OCT without blood vessels, individualized map, and customized sector) and recomputed the correlations. Main Outcome Measures Spearman correlation between structure and function. Results The highest baseline correlation was 0.52 (95% confidence interval [CI], 0.13–0.78) in the superior temporal ONH sector. Improved measurements increased the correlation marginally to 0.58 (95% CI, 0.21–0.81). Applying the individualized map to the large, predefined ONH sectors did not improve the correlation; however, using the individualized map with the single 30° ONH sector resulted in a large increase in correlation to 0.77 (95% CI, 0.47–0.92). Conclusions Using more precise visual field and OCT measurements did not improve structure–function correlation in our cohort, but customizing the ONH sector and its associated visual field points substantially improved correlation. We suggest using customized ONH sectors mapped to individually relevant visual field locations to unmask localized structural and functional loss.
105

Estudo genético da qualidade de carne em linhagem macho de frangos de corte / Genetic study of meat quality traits in a male broiler line

Gaya, Leila de Genova 01 September 2006 (has links)
O presente trabalho teve como objetivo estimar os parâmetros genéticos e fenotípicos das características de qualidade de carne e de características de desempenho, carcaça e composição corporal em uma linhagem macho de frangos fornecida pela Agroceres Ross Melhoramento Genético de Aves S. A. As aves faziam parte do programa denominado sib test, ou teste de irmãos, aonde são coletadas informações de carcaça dos irmãos dos indivíduos a serem selecionados na referida linhagem, estes chamados de rebanho elite. As características de desempenho analisadas foram peso à seleção (PS), peso ao abate (PA) e medidas de ultra-sonografia de músculo peitoral (US). As características de carcaça analisadas foram o peso de peito (PPEI), o peso eviscerado (PE) e o peso de pernas (PPER) e as características de composição corporal analisadas foram o peso da gordura abdominal (GOR), o peso do fígado (FIG) e o peso do coração (COR). As características de qualidade de carne analisadas foram: medida de pH inicial (pHi), medida de pH em 6 horas após o abate (pH6), medida de pH final (pHf), amplitude inicial de queda de pH (AMi), amplitude final de queda de pH (AMf), teor de luminosidade (L*), teor de vermelho (a*), teor de amarelo (b*), perdas de água por exsudação (EXSU), perdas de água por descongelamento (CONG), perdas de água por cozimento (COZ) e força de cisalhamento (FC). Os componentes de (co) variância foram estimados por verossimilhança restrita, utilizando-se o programa MTDFREML. A matriz de parentesco foi composta por 107.154 animais. Para as características pH6, pHf e L* foram estimados coeficientes de herdabilidade moderados; para as demais características estes coeficientes foram baixos. As estimativas de correlações genéticas obtidas não foram indicativas de associações importantes entre as características de qualidade de carne e as características de desempenho, carcaça e composição corporal, exceto pela seleção a favor de PS, que pode reduzir as perdas de água da carne. As estimativas de correlações genéticas encontradas entre as características de qualidade de carne puderam contribuir para o entendimento dos mecanismos relacionados à qualidade da carne na linhagem analisada, de modo que CONG, FC e L* foram características capazes de trazer respostas correlacionadas favoráveis às demais e em maior ou menor grau apresentarem capacidade de resposta à seleção, recomendando-se sua utilização como critério de seleção quando na existência de necessidade de melhoria na qualidade da carne na linhagem estudada. Contudo, esta necessidade não foi aparente, uma vez que as tendências genéticas das características de qualidade de carne, além de terem sido de pequena magnitude, foram em sua maioria favoráveis à qualidade da carne da linhagem analisada. / This research was conducted to estimate genetic and phenotypic parameters of meat quality, performance, carcass and body composition traits in a male broiler line provided by Agroceres Ross Melhoramento Genético de Aves S. A. Broilers measured belonged to a sib test program, in which data from sibs of the individuals to be selected in this line, called elite flock, are collected. Performance traits analyzed were body weight at selection (PS), body weight at slaughter (PA) and ultrasound records of pectoral muscle (US). Carcass traits analyzed were meat breast weight (PPEI), eviscerated body weight (PE) and leg weight (PPER) and the body composition traits analyzed were abdominal fat weight (GOR), liver weight (FIG) and heart weight (COR). Meat quality traits analyzed were: initial pH measure (pHi), pH measure at 6 hours after slaughter (pH6), final pH measure (pHf), initial range of pH fall (AMi), final range of pH fall (AMf), lightness (L*), redness (a*), yellowness (b*), weep losses (EXSU), drip losses (CONG), shrink losses (COZ) and shear force (FC). (Co) variance components were estimated by restricted maximum likelihood method, using the software MTDFREML. The numerator relationship matrix was composed by 107.154 individuals. For pH6, pHf and L*, moderate heritability coefficients were estimated; for the other traits these coefficients were low. Genetic correlation estimates obtained indicated a small association among meat quality traits and performance, carcass and body composition traits, except for the selection to PS, which seemed to be able to reduce water losses of meat. Genetic correlations estimates among meat quality traits could orientated the understanding of the mechanisms related to meat quality in the analyzed line; CONG, FC and L* seemed to be able to bring favorable correlationed responses, so it was recommended its use as selection criterion if existing the necessity of improving the meat quality in the analyzed line. However, this necessity was not apparent, since the genetic trends of meat quality traits were small and favorable to meat quality in the analyzed broiler line.
106

Struktūrinių ir funkcinių dydžių sąsajos sveikiems vaikams ir vaikams su protiniu atsilikimu / Correlations of structural and functional parameters for healthy and mental defective children

Kulakauskienė, Loreta 16 June 2005 (has links)
SUMMARY Speciality of Kinesiology CORRELATIONS OF STRUCTURAL AND FUNCTIONAL PARAMETERS FOR HEALTHY AND MENTAL DEFECTIVE CHILDREN Author: Lorita Kulakauskienė. Supervisor: Prof., Habil. Dr. Alfonsas Vainoras. The work has been carried out at: Kaunas University of Medicine, Faculty of Public Health, Department of Kinesiology and Sport medicine, 2003-2005. The aim of the study: to determine correlations of structural and functional parameters for healthy and mental defective children. Objectives: 1. To compare groups of healthy and mental defective children together by means of measured structural and functional parameters. 2. To size up essential correlations of structural and functional parameters. 3. To examine possible reasons of different correlations between two groups of investigative children. 4. To look into organism, as a complex system, features in both groups of investigative children. The object of the study: two groups of children. One of them – 22 mental defective children (mean age – 14,9 years), and the other – 22 healthy children (mean age – 15,04 years). Methods of the study: anthropometry, measuring arterial blood pressure, cirthometry, skoliometry, electrocardiography and mathematical statistics methods. Results: Means of arterial blood pressure and electrocardiographical parameter aQRS were statistically significantly (p<0,05) more in healthy children group (S), but means of cirthometry parameter C_K and skoliometry parameter Sk_3 - in mental defective... [to full text]
107

Estudo genético da qualidade de carne em linhagem macho de frangos de corte / Genetic study of meat quality traits in a male broiler line

Leila de Genova Gaya 01 September 2006 (has links)
O presente trabalho teve como objetivo estimar os parâmetros genéticos e fenotípicos das características de qualidade de carne e de características de desempenho, carcaça e composição corporal em uma linhagem macho de frangos fornecida pela Agroceres Ross Melhoramento Genético de Aves S. A. As aves faziam parte do programa denominado sib test, ou teste de irmãos, aonde são coletadas informações de carcaça dos irmãos dos indivíduos a serem selecionados na referida linhagem, estes chamados de rebanho elite. As características de desempenho analisadas foram peso à seleção (PS), peso ao abate (PA) e medidas de ultra-sonografia de músculo peitoral (US). As características de carcaça analisadas foram o peso de peito (PPEI), o peso eviscerado (PE) e o peso de pernas (PPER) e as características de composição corporal analisadas foram o peso da gordura abdominal (GOR), o peso do fígado (FIG) e o peso do coração (COR). As características de qualidade de carne analisadas foram: medida de pH inicial (pHi), medida de pH em 6 horas após o abate (pH6), medida de pH final (pHf), amplitude inicial de queda de pH (AMi), amplitude final de queda de pH (AMf), teor de luminosidade (L*), teor de vermelho (a*), teor de amarelo (b*), perdas de água por exsudação (EXSU), perdas de água por descongelamento (CONG), perdas de água por cozimento (COZ) e força de cisalhamento (FC). Os componentes de (co) variância foram estimados por verossimilhança restrita, utilizando-se o programa MTDFREML. A matriz de parentesco foi composta por 107.154 animais. Para as características pH6, pHf e L* foram estimados coeficientes de herdabilidade moderados; para as demais características estes coeficientes foram baixos. As estimativas de correlações genéticas obtidas não foram indicativas de associações importantes entre as características de qualidade de carne e as características de desempenho, carcaça e composição corporal, exceto pela seleção a favor de PS, que pode reduzir as perdas de água da carne. As estimativas de correlações genéticas encontradas entre as características de qualidade de carne puderam contribuir para o entendimento dos mecanismos relacionados à qualidade da carne na linhagem analisada, de modo que CONG, FC e L* foram características capazes de trazer respostas correlacionadas favoráveis às demais e em maior ou menor grau apresentarem capacidade de resposta à seleção, recomendando-se sua utilização como critério de seleção quando na existência de necessidade de melhoria na qualidade da carne na linhagem estudada. Contudo, esta necessidade não foi aparente, uma vez que as tendências genéticas das características de qualidade de carne, além de terem sido de pequena magnitude, foram em sua maioria favoráveis à qualidade da carne da linhagem analisada. / This research was conducted to estimate genetic and phenotypic parameters of meat quality, performance, carcass and body composition traits in a male broiler line provided by Agroceres Ross Melhoramento Genético de Aves S. A. Broilers measured belonged to a sib test program, in which data from sibs of the individuals to be selected in this line, called elite flock, are collected. Performance traits analyzed were body weight at selection (PS), body weight at slaughter (PA) and ultrasound records of pectoral muscle (US). Carcass traits analyzed were meat breast weight (PPEI), eviscerated body weight (PE) and leg weight (PPER) and the body composition traits analyzed were abdominal fat weight (GOR), liver weight (FIG) and heart weight (COR). Meat quality traits analyzed were: initial pH measure (pHi), pH measure at 6 hours after slaughter (pH6), final pH measure (pHf), initial range of pH fall (AMi), final range of pH fall (AMf), lightness (L*), redness (a*), yellowness (b*), weep losses (EXSU), drip losses (CONG), shrink losses (COZ) and shear force (FC). (Co) variance components were estimated by restricted maximum likelihood method, using the software MTDFREML. The numerator relationship matrix was composed by 107.154 individuals. For pH6, pHf and L*, moderate heritability coefficients were estimated; for the other traits these coefficients were low. Genetic correlation estimates obtained indicated a small association among meat quality traits and performance, carcass and body composition traits, except for the selection to PS, which seemed to be able to reduce water losses of meat. Genetic correlations estimates among meat quality traits could orientated the understanding of the mechanisms related to meat quality in the analyzed line; CONG, FC and L* seemed to be able to bring favorable correlationed responses, so it was recommended its use as selection criterion if existing the necessity of improving the meat quality in the analyzed line. However, this necessity was not apparent, since the genetic trends of meat quality traits were small and favorable to meat quality in the analyzed broiler line.
108

Critical slowing down and error analysis of lattice QCD simulations

Virotta, Francesco 07 May 2012 (has links)
In dieser Arbeit untersuchen wir das Critical Slowing down der Gitter-QCD Simulationen. Wir führen eine Vorstudie in der quenched Approximation durch, in der wir feststellen, dass unsere Schätzung der exponentiellen Autokorrelation wie $\tauexp(a) \sim a^{-5} $ skaliert, wobei $a$ der Gitterabstand ist. In unquenched Simulationen mit O(a)-verbesserten Wilson-Fermionen finden wir ein ähnliches Skalierungsgesetz. Die Diskussion wird von einem gro\ss{}en Satz an Ensembles sowohl in reiner Eichtheorie als auch in der Theorie mit zwei entarteten Seequarks unterstützt. Wir haben darüber hinaus die Wirkung von langsamen algorithmischen Modi in der Fehleranalyse des Erwartungswertes von typischen Gitter-QCD-Observablen (hadronische Matrixelemente und Massen) untersucht. Im Kontext der Simulationen, die durch langsame Modi betroffen sind, schlagen wir vor und testen eine Methode, um zuverlässige Schätzungen der statistischen Fehler zu bekommen. Diese Methode soll in dem typischen Simulationsbereich der Gitter-QCD helfen, nämlich dann, wenn die gesamte erfasste Statistik O(10)\tauexp ist. Dies ist der typische Fall bei Simulationen in der Nähe des Kontinuumslimes, wo der Rechenaufwand für die Erzeugung von zwei unabhängigen Datenpunkten sehr gro\ss{} sein kann. Schlie\ss{}lich diskutieren wir die Skalenbestimmung in N_f=2-Simulationen mit der Kaon Zerfallskonstante f_K als experimentellem Input. Die Methode wird zusammen mit einer gründlichen Diskussion der angewandten Fehleranalyse erklärt. Eine Beschreibung der öffentlich zugänglichen Software, die für die Fehleranalyse genutzt wurde, ist eingeschlossen. / In this work we investigate the critical slowing down of lattice QCD simulations. We perform a preliminary study in the quenched approximation where we find that our estimate of the exponential auto-correlation time scales as $\tauexp(a)\sim a^{-5}$, where $a$ is the lattice spacing. In unquenched simulations with O(a) improved Wilson fermions we do not obtain a scaling law but find results compatible with the behavior that we find in the pure gauge theory. The discussion is supported by a large set of ensembles both in pure gauge and in the theory with two degenerate sea quarks. We have moreover investigated the effect of slow algorithmic modes in the error analysis of the expectation value of typical lattice QCD observables (hadronic matrix elements and masses). In the context of simulations affected by slow modes we propose and test a method to obtain reliable estimates of statistical errors. The method is supposed to help in the typical algorithmic setup of lattice QCD, namely when the total statistics collected is of O(10)\tauexp. This is the typical case when simulating close to the continuum limit where the computational costs for producing two independent data points can be extremely large. We finally discuss the scale setting in Nf=2 simulations using the Kaon decay constant f_K as physical input. The method is explained together with a thorough discussion of the error analysis employed. A description of the publicly available code used for the error analysis is included.
109

Influência de parâmetros moleculares em funções de correlação temporal na dinâmica de solvatação mecânica / Influence of molecular parameters on time correlations functions of mechanical solvation dynamics

Martins, Marcio Marques January 2004 (has links)
No presente trabalho descrevemos nossos resultados relativos à investigação da dinâmica de solvatação mecânica por meio de simulações por dinâmica molecular, respeitando o regime da resposta linear, em sistemas-modelo de argônio líquido com um soluto monoatômico ou diatômico dissolvido. Estudamos sistematicamente a influência dos parâmetros moleculares dos solutos (tamanho, polarizabilidade) e da densidade frente a vários modelos de solvatação. Funções de Correlação Temporal da Energia de Solvatação foram calculadas com relação à correlações de n-corpos (n = 2; 3) distinguindo interações repulsivas e atrativas para ambos os sistemas líquidos. Também obtivemos segundas derivadas temporais dessas funções referindo-se à parcelas translacionais, rotacionais e roto-translacionais na solução do diatômico. Encontramos que funções de correlação temporal coletivas podem ser razoavelmente bem aproximadas por correlações binárias a densidades baixas e, a densidades altas, correlações ternárias tornam-se mais importantes produzindo um descorrelacionamento mais rápido das funções coletivas devido a efeitos de cancelamento parciais. As funções de correlação para interações repulsivas e atrativas exibem comportamentos dinâmicos independentes do modelo de solvatação devido a fatores de escalonamento linear que afetam apenas as amplitudes das dessas funções de correlação temporal. Em geral, os sistemas com grau de liberdade rotacional apresentam tempos de correlação mais curtos para a dinâmica coletiva e tempos de correlação mais longos para as funções binárias e ternárias. Finalmente, esse estudo mostra que os sistemas contendo o diatômico relaxam-se predominantemente por mecanismos translacionais binários em modelos de solvatação envolvendo alterações apenas na polarizabilidade do soluto, e por mecanismos rotacionais atrativos binários em modelos envolvendo alterações no comprimento de ligação. / In the present work, we describe our results concerning our molecular dynamics investigation of the mechanical solvation dynamics within the linear response regime in model systems composed by liquid argon with a monoatomic or diatomic solute. The effect of molecular parameters (size, polarizability) and density has been elucidated for various solvation models. Time Correlation Functions for the solvation energy were calculated and separated into n-body (n = 2; 3) contributions distinguishing repulsive and attractive interactions in both liquid systems. In addition, we computed second time derivatives of these functions in order to describe translational, rotational, and roto-translational portions in the solutions containing the diatomics. We found that collective time correlation functions are well described by binary correlations at low liquid densities and, at high densities, ternary correlations become more important producing faster decaying collective time correlation functions due to partial cancellation effects. The repulsive and attractive time correlation functions exhibit a dynamic behavior that is independent on the solvation model due to linear scaling factors that only affect the absolute amplitudes of these functions. In general, the systems involving a rotational degree of freedom furnish smaller correlation times for the collective solvation dynamics, but stronger correlated two-body and three-body terms. Finally, this study shows that the solvation dynamics for the solution containing the diatomics relaxes predominatly by binary translational mechanisms when solvation models involving changes only in the polarizability parameter are considered. Binary attractive rotational mechanism become important in models with changes in the bond length.
110

Influência de parâmetros moleculares em funções de correlação temporal na dinâmica de solvatação mecânica / Influence of molecular parameters on time correlations functions of mechanical solvation dynamics

Martins, Marcio Marques January 2004 (has links)
No presente trabalho descrevemos nossos resultados relativos à investigação da dinâmica de solvatação mecânica por meio de simulações por dinâmica molecular, respeitando o regime da resposta linear, em sistemas-modelo de argônio líquido com um soluto monoatômico ou diatômico dissolvido. Estudamos sistematicamente a influência dos parâmetros moleculares dos solutos (tamanho, polarizabilidade) e da densidade frente a vários modelos de solvatação. Funções de Correlação Temporal da Energia de Solvatação foram calculadas com relação à correlações de n-corpos (n = 2; 3) distinguindo interações repulsivas e atrativas para ambos os sistemas líquidos. Também obtivemos segundas derivadas temporais dessas funções referindo-se à parcelas translacionais, rotacionais e roto-translacionais na solução do diatômico. Encontramos que funções de correlação temporal coletivas podem ser razoavelmente bem aproximadas por correlações binárias a densidades baixas e, a densidades altas, correlações ternárias tornam-se mais importantes produzindo um descorrelacionamento mais rápido das funções coletivas devido a efeitos de cancelamento parciais. As funções de correlação para interações repulsivas e atrativas exibem comportamentos dinâmicos independentes do modelo de solvatação devido a fatores de escalonamento linear que afetam apenas as amplitudes das dessas funções de correlação temporal. Em geral, os sistemas com grau de liberdade rotacional apresentam tempos de correlação mais curtos para a dinâmica coletiva e tempos de correlação mais longos para as funções binárias e ternárias. Finalmente, esse estudo mostra que os sistemas contendo o diatômico relaxam-se predominantemente por mecanismos translacionais binários em modelos de solvatação envolvendo alterações apenas na polarizabilidade do soluto, e por mecanismos rotacionais atrativos binários em modelos envolvendo alterações no comprimento de ligação. / In the present work, we describe our results concerning our molecular dynamics investigation of the mechanical solvation dynamics within the linear response regime in model systems composed by liquid argon with a monoatomic or diatomic solute. The effect of molecular parameters (size, polarizability) and density has been elucidated for various solvation models. Time Correlation Functions for the solvation energy were calculated and separated into n-body (n = 2; 3) contributions distinguishing repulsive and attractive interactions in both liquid systems. In addition, we computed second time derivatives of these functions in order to describe translational, rotational, and roto-translational portions in the solutions containing the diatomics. We found that collective time correlation functions are well described by binary correlations at low liquid densities and, at high densities, ternary correlations become more important producing faster decaying collective time correlation functions due to partial cancellation effects. The repulsive and attractive time correlation functions exhibit a dynamic behavior that is independent on the solvation model due to linear scaling factors that only affect the absolute amplitudes of these functions. In general, the systems involving a rotational degree of freedom furnish smaller correlation times for the collective solvation dynamics, but stronger correlated two-body and three-body terms. Finally, this study shows that the solvation dynamics for the solution containing the diatomics relaxes predominatly by binary translational mechanisms when solvation models involving changes only in the polarizability parameter are considered. Binary attractive rotational mechanism become important in models with changes in the bond length.

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