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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.
51

Centralidades em redes espaciais urbanas e localização de atividades econômicas / Centrality in urban spatial networks and location of economic activities

Lima, Leonardo da Silva e January 2015 (has links)
Nos últimos anos, o estudo de propriedades de redes espaciais urbanas conhecidas como centralidades, tem sido utilizado com frequência para descrever fenômenos de ordem sócio-econômica associados à forma da cidade. Autores têm sugerido que centralidades são capazes de descrever a estrutura espacial urbana (KRAFTA, 1994; ANAS et al., 1998) e, portanto através do estudo de centralidades, é possível reconhecer os espaços que mais concentram fluxos, os que possuem os maiores valores de renda da terra, os mais seguros, entre outros aspectos que parecem estar diretamente relacionados com o fenômeno urbano. A hipótese dessa pesquisa admite que centralidades em redes espaciais urbanas desempenham um papel fundamental na formação da estrutura espacial urbana e na maneira como são organizados os usos do solo da cidade. Assim, essa pesquisa investiga qual modelo de centralidade, processado sobre diversas formas de se descrever o espaço urbano na forma de uma rede, é capaz de apresentar resultados mais fortemente correlacionados com a distribuição espacial de atividades econômicas urbanas. Nessa pesquisa são avaliados cinco modelos de centralidade, aplicados sobre diferentes redes espaciais urbanas com a intenção de se verificar qual deles apresenta maior correlação com a ocorrência de atividades econômicas. Para realizar tal exercício, esses modelos são aplicados sobre três tipos de redes espaciais urbanas (axial, nodal e trechos de rua) – oriundas da configuração espacial de três cidades brasileiras – processados de forma geométrica e topológica. Os modelos de centralidade aplicados são conhecidos como centralidade por Alcance (SEVTSUK; 2010), centralidade por Excentricidade (PORTA et al.; 2009, 2011), centralidade por Intermediação (FREEMAN, 1977), centralidade por Intermediação Planar (KRAFTA, 1994) e centralidade por Proximidade (INGRAM, 1971). O coeficiente de correlação Pearson (r) é utilizado como ferramenta capaz de descrever qual modelo de centralidade, associado a qual tipo de representação espacial e qual modo de processamento de distâncias melhor se correlaciona com a distribuição de atividades econômicas urbanas nessas cidades. As evidências encontradas nessa pesquisa sugerem que os modelos de centralidade por Alcance, centralidade por Excentricidade e centralidade por Intermediação Planar destacam-se em comparação com os demais modelos processados. Além disso, os valores de correlação Pearson (r) mais relevantes foram obtidos quando os modelos de centralidade foram processados considerando-se a geometria da rede formada por trechos de rua, indicando que um tipo de representação espacial mais desagregada e processada de forma geométrica seria mais capaz de apresentar os melhores valores de correlação para a compreensão do fenômeno urbano estudado. / In recent years, the study of urban spatial networks has been often used to describe urban phenomena associated with the shape of the city. Researches suggested that centralities are able to describe the urban spatial structure (KRAFTA, 1994; ANAS et al., 1998) and then it is possible to recognize the spaces with more flows, which have the highest values of land revenue, the safest, among other aspects related to urban phenomenon. The hypothesis of this research accepts that centrality in urban spatial networks play a key role for the urban spatial structure and the way of land uses is organized. Thus, there would be some measures of centrality in urban spatial networks that would be more associated with economic activities occurring in the city. The research will evaluate five measures of centrality applied on three types of urban spatial networks (axial map, node map and segment map). Therefore we will use five models of centrality in urban spatial networks known as reach (SEVTSUK, MEKONNEN, 2012), straightness (PORTA et al., 2006b), betweenness (FREEMAN, 1977), planar betweenness (KRAFTA, 1994) and closeness (INGRAM, 1971) in order to determine which this most highly correlated with the occurrence of economic activities. The relationships between these measures of centrality and locations of economic activities are examined in three Brazilian cities, using as methodology the Pearson correlation coefficient (r). The highest correlation between the results of centrality in urban spatial networks and the location of economic activities will suggest which centrality measure, way of to describe urban space like a network and distance processing method (euclidian or topologic) is more associated with the occurrence of these activities in the city. The results indicate that Reach, Straightness and Planar Betweenness are most outstanding models of centrality. In addition, Pearson correlation coefficients (r) most relevant were obtained when models of centrality are processed considering euclidian paths in the street segments network, suggesting that this type of spatial network and distances processing method generates centralities with more significant correlation values within the urban phenomenon studied.
52

Centralidades em redes espaciais urbanas e localização de atividades econômicas / Centrality in urban spatial networks and location of economic activities

Lima, Leonardo da Silva e January 2015 (has links)
Nos últimos anos, o estudo de propriedades de redes espaciais urbanas conhecidas como centralidades, tem sido utilizado com frequência para descrever fenômenos de ordem sócio-econômica associados à forma da cidade. Autores têm sugerido que centralidades são capazes de descrever a estrutura espacial urbana (KRAFTA, 1994; ANAS et al., 1998) e, portanto através do estudo de centralidades, é possível reconhecer os espaços que mais concentram fluxos, os que possuem os maiores valores de renda da terra, os mais seguros, entre outros aspectos que parecem estar diretamente relacionados com o fenômeno urbano. A hipótese dessa pesquisa admite que centralidades em redes espaciais urbanas desempenham um papel fundamental na formação da estrutura espacial urbana e na maneira como são organizados os usos do solo da cidade. Assim, essa pesquisa investiga qual modelo de centralidade, processado sobre diversas formas de se descrever o espaço urbano na forma de uma rede, é capaz de apresentar resultados mais fortemente correlacionados com a distribuição espacial de atividades econômicas urbanas. Nessa pesquisa são avaliados cinco modelos de centralidade, aplicados sobre diferentes redes espaciais urbanas com a intenção de se verificar qual deles apresenta maior correlação com a ocorrência de atividades econômicas. Para realizar tal exercício, esses modelos são aplicados sobre três tipos de redes espaciais urbanas (axial, nodal e trechos de rua) – oriundas da configuração espacial de três cidades brasileiras – processados de forma geométrica e topológica. Os modelos de centralidade aplicados são conhecidos como centralidade por Alcance (SEVTSUK; 2010), centralidade por Excentricidade (PORTA et al.; 2009, 2011), centralidade por Intermediação (FREEMAN, 1977), centralidade por Intermediação Planar (KRAFTA, 1994) e centralidade por Proximidade (INGRAM, 1971). O coeficiente de correlação Pearson (r) é utilizado como ferramenta capaz de descrever qual modelo de centralidade, associado a qual tipo de representação espacial e qual modo de processamento de distâncias melhor se correlaciona com a distribuição de atividades econômicas urbanas nessas cidades. As evidências encontradas nessa pesquisa sugerem que os modelos de centralidade por Alcance, centralidade por Excentricidade e centralidade por Intermediação Planar destacam-se em comparação com os demais modelos processados. Além disso, os valores de correlação Pearson (r) mais relevantes foram obtidos quando os modelos de centralidade foram processados considerando-se a geometria da rede formada por trechos de rua, indicando que um tipo de representação espacial mais desagregada e processada de forma geométrica seria mais capaz de apresentar os melhores valores de correlação para a compreensão do fenômeno urbano estudado. / In recent years, the study of urban spatial networks has been often used to describe urban phenomena associated with the shape of the city. Researches suggested that centralities are able to describe the urban spatial structure (KRAFTA, 1994; ANAS et al., 1998) and then it is possible to recognize the spaces with more flows, which have the highest values of land revenue, the safest, among other aspects related to urban phenomenon. The hypothesis of this research accepts that centrality in urban spatial networks play a key role for the urban spatial structure and the way of land uses is organized. Thus, there would be some measures of centrality in urban spatial networks that would be more associated with economic activities occurring in the city. The research will evaluate five measures of centrality applied on three types of urban spatial networks (axial map, node map and segment map). Therefore we will use five models of centrality in urban spatial networks known as reach (SEVTSUK, MEKONNEN, 2012), straightness (PORTA et al., 2006b), betweenness (FREEMAN, 1977), planar betweenness (KRAFTA, 1994) and closeness (INGRAM, 1971) in order to determine which this most highly correlated with the occurrence of economic activities. The relationships between these measures of centrality and locations of economic activities are examined in three Brazilian cities, using as methodology the Pearson correlation coefficient (r). The highest correlation between the results of centrality in urban spatial networks and the location of economic activities will suggest which centrality measure, way of to describe urban space like a network and distance processing method (euclidian or topologic) is more associated with the occurrence of these activities in the city. The results indicate that Reach, Straightness and Planar Betweenness are most outstanding models of centrality. In addition, Pearson correlation coefficients (r) most relevant were obtained when models of centrality are processed considering euclidian paths in the street segments network, suggesting that this type of spatial network and distances processing method generates centralities with more significant correlation values within the urban phenomenon studied.
53

Correlação intraclasse de Pearson para pares repetidos: comparação entre dois estimadores / Intraclass correlation of Pearson repeated for couples: comparison between two estimators

Denise Pimentel Bergamaschi 12 March 1999 (has links)
Objetivo. Comparar, teórica e empiricamente, dois estimadores do coeficiente de correlação intraclasse momento-produto de Pearson para pares repetidos Pi. O primeiro é o estimador \"natural\", obtido mediante a correlação momento-produto de Pearson para membros de uma mesma classe (rI) e o segundo, obtido como função de componentes de variância (icc). Métodos. Comparação teórica e empírica dos parâmetros e estimadores. A comparação teórica envolve duas definições do coeficiente de correlação intraclasse PI como medida de confiabilidade (*), para o caso de duas réplicas, assim como uma apresentação da técnica de análise de variância e a definição e interpretação dos estimadores ri e icc. A comparação empírica é realizada mediante um estudo de simulação Monte Carlo com a geração de pares de valores correlacionados segundo o coeficiente de correlação intraclasse, momento-produto de Pearson para pares repetidos. Os pares de valores são distribuídos segundo uma distribuição Normal bivariada, com valores do tamanho da amostra e da correlação intraclasse previamente fixados em: n= 15, 30 e 45 e pI = {O; 0,15; 0,30; 0,45; 0,60; 0,75; 0,9}. Resultados. Comparando-se o vício e o erro quadrático médio dos estimadores, bem como as amplitudes dos intervalos de confiança, tem-se como resultado que o vício de icc foi sempre menor que o vício de rI, mesmo ocorrendo com o erro quadrático médio. Conclusões. O icc é um estimador melhor, principalmente para n pequeno (por exemplo 15). Para valores maiores de n (30 ou mais), os estimadores produzem resultados iguais até a segunda casa decimal. / Objective. This thesis presents and compares, theoretically and empirically, two estimators of the intraclass correlation coefficient pI, defined as Pearson\'s pairwise intraclass correlation coefficient. The first is the \"natural\" estimator, obtained by Pearson\'s moment-product correlation for members of one class (rI) while the second was obtained as a function of components of variance (icc). Methods. Theoretical and empirical comparison of the parameters and estimators are performed. The theoretical comparison involves two definitions of the intrac1ass correlation coefficient pI as a measure of reliability (*) for two repeated measurements in the same class and the presentation of the technique of analysis of variance, as well as for the definition and interpretation of the estimators ri and icc. The empirical comparison was carried out by means of a Monte Carlo simulation study of pairs of correlated values according Pearson\'s pairwise correlation. The pairs of values follow a normal bivariate distribution, with correlation values and sample size previously fixed: n= 15, 30 e 45 and Pl = . Results. Bias and mean square error for the estimators were compared as well as the range of the intervals of confidence. The comparison shows that the bias of icc is always smaller than of rI This also applies to the mean square error. Conclusions. The icc is a better estimator, especially for n less than or equal to 15. For larger samples sízes (n 30 or more), the estimators produce results that are equal to the second decimal place. (*) Fórmula
54

Analysis of Monthly Suspended Sediment Load in Rivers and Streams Using Linear Regression and Similar Precipitation Data

Echiejile, Faith 18 August 2021 (has links)
No description available.
55

The Shape Synthesis of Antenna Decoupling Surfaces

Raei, Mohammed 04 June 2021 (has links)
Although multi-element antenna (MEA) systems are already used in some modern wireless communication systems, the issue of mutual coupling between elements remains a challenge during MEA system design. Indeed, communications engineers continue to bemoan the fact that that the antenna elements are often still designed with such coupling as an afterthought. Thus, some authors have used the decoupling surface (DS) idea, whereby a separate DS is added to the MEA systems to reduce the above coupling. Whereas a DS may indeed lower the coupling levels between the elements of a given MEA system, it usually changes the other performance parameters as well, and in an undesirable way. Thus, this design route is a complicated one that is not easily affected. In this thesis we propose, for the first time, a new design process for MEA systems based on shape synthesis. The MEA system performance indicators are combined into an objective that sets the goal of the shape synthesis procedure. The application of the proposed design process is illustrated for three different geometrical arrangements of patch antennas and decoupling surfaces. This confirms the efficacy of the new design method.
56

Comprehension and Interpretation of Common Language Effect Size Displays

Moracz, Kelle 27 November 2019 (has links)
No description available.
57

Zone-Based Nonuniformity Correction Algorithm for Removing Fixed Pattern Noise in Hyperspectral Images

Nguyen, Linh Duy 20 December 2022 (has links)
No description available.
58

Formulering av HPWS i ideella föreningar : En studie om implementationsmöjligheter av HPWS i ensvensk esportförening

Linnarsson, Rasmus January 2023 (has links)
This study aims to examine and identify possibilities andprerequisites for implementing a High Performance Work System(HPWS) in a Swedish non-profit association’s operations. Theessay assumes a set of frameworks in the form of HPWS practiceswhich are defined in previous research in order to determine andevaluate the implementation possibilities in the association. Thestudy takes place in “SRL Spelförening”, a non-profit associationwhich conduct welfare processes in the form of esports in theSwedish grassroot scene. The association has during its lifespanundergone large changes within all aspects of its operation – notleast the structure of work processes, something that has meantthat many parts of the workflow are unorganized and unstructured.This study analyzes the current state of the association’sprocesses with a quantitative interview approach focused on a setof work-related variables. The data that is generated is then usedas a control tool when the association’s prevalent prerequisites ofHPWS are to be determined. The data was also applied in a linearregression model generating correlation coefficients among thework-related variables – information which in turn gets applied inorder to decide the association’s individual attitude to HPWS. Theanalysis points to the association generally meeting the HPWSrequirements which were cited in earlier research. Some aspectswere however determined to lie beneath the bar and thereforerequire changes in accordance with earlier similar HPWS relatedcases. Furthermore, the correlation results show that theassociation’s workers’ overall attitude towards HPWS was positive,where a higher appreciation of a HPWS was related to higherengagement and lower turnover intention.
59

Paradoxes and Priors in Bayesian Regression

Som, Agniva 30 December 2014 (has links)
No description available.
60

Evaluation of the validity of IMU sensors measuring wrist angular velocity by comparison with an optical motion tracking system / Utvärdering av validiteten hos IMU-mätningar av handledshastighet genom jämförelse med ett optiskt mätsystem

Tesfaldet, Mogos Tseletu January 2020 (has links)
There is a need for objective methods for wrist angular velocity measurements for accurate risk assessments because there is a high frequency of musculoskeletal disorder in workers. The goal of this project was to validate the accuracy of inertial measurement unit sensors to measure the angular velocity. More specifically, the purpose of this master thesis project was to apply an alternative algorithm to compute the markers velocity, other than the one from the optical system that Jenny Wingqvist, and Josephine Lantz used. The project used an experimental data of 10 participants from the previous project done by Jenny Wingqvist and Josephine Lantz. To validate the accuracy, the data of angular velocity of the sensors was compared with the data of angular velocity of markers. The lowest mean value of the root mean square differences value was 23.5 degrees/s during flexion and deviation standard movements at 40 BPM (Beats Per Minute) and the maximum value was 110.5 degrees/s at 140 BPM. The mean value of the correlation coefficients between markers and sensors angular velocities in standard movements of flexion and deviation were 0.85, 0.88, and 0.89 at 40 BPM, 90 BPM, and 140 BPM, respectively. The smallest and the largest mean value of the absolute difference in 50th percentile was found in 40 BPM (19.4±11.3), and 140 BPM (51.2±28.5) respectively. The decorrelation coefficient between the subjects 50th percentile of the angular velocity was 0.91 for the standard movements. The upper limit of agreement for the standard movements was 78.36 degrees/s, while the lower limit of agreement was -13.76 degrees/s.  The results show that the error was too large, so there is a need of further research to measure the wrist angular velocity using IMU sensors.

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