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Network evolution: the origins, development and effectiveness of Manitoba's railway systemMcCombe, Christopher G. L. 13 September 2011 (has links)
This thesis examines the characteristics of railway infrastructure development and associated issues in Manitoba, Canada. The period under consideration dates from when the first tracks were laid in 1878 through to the completion of the Hudson Bay Railway in 1929. Setting the scene is a template for railway development in general, one that allows hypotheses to be drawn that are specific to Manitoba. In order to test those hypotheses it is necessary to first provide a comprehensive overview of the historical evolution of the railway network. Next, aspects of graph theory are reviewed, identifying the methodology most appropriate for a spatial analysis of railway networks. This analysis attempts to draw conclusions about the relationship between the railway companies and the governments, people and geography that they were compelled to deal with. The testing of these forms revealed that while the Manitoba railway network is very complex, it never arrived at the maximum possible complexity.
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Multivariate Multiscale Analysis of Neural Spike TrainsRamezan, Reza 10 December 2013 (has links)
This dissertation introduces new methodologies for the analysis of neural spike trains. Biological properties of the nervous system, and how they are reflected in neural data, can motivate specific analytic tools. Some of these biological aspects motivate multiscale frameworks, which allow for simultaneous modelling of the local and global behaviour of neurons. Chapter 1 provides the preliminary background on the biology of the nervous system and details the concept of information and randomness in the analysis of the neural spike trains. It also provides the reader with a thorough literature review on the current statistical models in the analysis of neural spike trains. The material presented in the next six chapters (2-7) have been the focus of three papers, which have either already been published or are being prepared for publication.
It is demonstrated in Chapters 2 and 3 that the multiscale complexity penalized likelihood method, introduced in Kolaczyk and Nowak (2004), is a powerful model in the simultaneous modelling of spike trains with biological properties from different time scales. To detect the periodic spiking activities of neurons, two periodic models from the literature, Bickel et al. (2007, 2008); Shao and Li (2011), were combined and modified in a multiscale penalized likelihood model. The contributions of these chapters are (1) employinh a powerful visualization tool, inter-spike interval (ISI) plot, (2) combining the multiscale method of Kolaczyk and Nowak (2004) with the periodic models ofBickel et al. (2007, 2008) and Shao and Li (2011), to introduce the so-called additive and multiplicative models for the intensity function of neural spike trains and introducing a cross-validation scheme to estimate their tuning parameters, (3) providing the numerical bootstrap confidence bands for the multiscale estimate of the intensity
function, and (4) studying the effect of time-scale on the statistical properties of spike counts.
Motivated by neural integration phenomena, as well as the adjustments for the neural refractory period, Chapters 4 and 5 study the Skellam process and introduce the Skellam Process with Resetting (SPR). Introducing SPR and its application in the analysis of neural spike trains is one of the major contributions of this dissertation. This stochastic process is biologically plausible, and unlike the Poisson process, it does not suffer from limited dependency structure. It also has multivariate generalizations for the simultaneous analysis of multiple spike trains. A computationally efficient recursive algorithm for the estimation of the parameters of SPR is introduced in Chapter 5. Except for the literature review at the beginning of Chapter 4, the rest of the material within these two chapters is original. The specific contributions of Chapters 4 and 5 are (1) introducing the Skellam Process with Resetting as a statistical tool to analyze neural spike trains and studying its properties, including all theorems and lemmas provided in Chapter 4, (2) the two fairly standard definitions of the Skellam process (homogeneous and inhomogeneous) and the proof of their equivalency, (3) deriving the likelihood function based on the observable data (spike trains) and developing a computationally efficient recursive algorithm for parameter estimation, and (4) studying the effect of time scales on the SPR model.
The challenging problem of multivariate analysis of the neural spike trains is addressed in Chapter 6. As far as we know, the multivariate models which are available in the literature suffer from limited dependency structures. In particular, modelling negative correlation among spike trains is a challenging problem. To address this issue, the multivariate Skellam distribution, as well as the multivariate Skellam process, which both have flexible dependency structures, are developed. Chapter 5 also introduces a multivariate version of Skellam Process with Resetting (MSPR), and a so-called profile-moment likelihood estimation of its parameters. This chapter generalizes the results of Chapter 4 and 5, and therefore, except for the brief literature review provided at the beginning of the chapter, the remainder of the material is original work. In particular, the contributions of this chapter are (1) introducing multivariate Skellam distribution, (2) introducing two definitions of the Multivariate Skellam process in both homogeneous and inhomogeneous cases and proving their equivalence, (3) introducing Multivariate Skellam Process with Resetting (MSPR) to simultaneously model spike trains from an ensemble of neurons, and (4) utilizing the so-called profile-moment likelihood method to compute estimates of the parameters of MSPR.
The discussion of the developed methodologies as well as the ``next steps'' are outlined in Chapter 7.
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Network evolution: the origins, development and effectiveness of Manitoba's railway systemMcCombe, Christopher G. L. 13 September 2011 (has links)
This thesis examines the characteristics of railway infrastructure development and associated issues in Manitoba, Canada. The period under consideration dates from when the first tracks were laid in 1878 through to the completion of the Hudson Bay Railway in 1929. Setting the scene is a template for railway development in general, one that allows hypotheses to be drawn that are specific to Manitoba. In order to test those hypotheses it is necessary to first provide a comprehensive overview of the historical evolution of the railway network. Next, aspects of graph theory are reviewed, identifying the methodology most appropriate for a spatial analysis of railway networks. This analysis attempts to draw conclusions about the relationship between the railway companies and the governments, people and geography that they were compelled to deal with. The testing of these forms revealed that while the Manitoba railway network is very complex, it never arrived at the maximum possible complexity.
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Probabilistic Characterization of Neuromuscular Disease: Effects of Class Structure and Aggregation MethodsFarkas, Charles January 2010 (has links)
Neuromuscular disorders change the underlying structure and function of motor units within a muscle, and are detected using needle electromyography. Currently, inferences about the presence or absence of disease are made subjectively and are largely impression-based. Quantitative electromyography (QEMG) attempts to improve upon the status quo by providing greater levels of precision, objectivity and reproducibility through numeric analysis, however, their results must be transparently presented and explained to be clinically viable.
The probabilistic muscle characterization (PMC) model is ideally suited for a clinical decision support system (CDSS) and has many analogues to the subjective analysis currently used. To improve disease characterization performance globally, a hierarchical classification strategy is developed that accounts for the wide range of MUP feature values present at different levels of involvement (LOI) of a disorder. To improve utility, methods for detecting LOI are considered that balance the accuracy in reporting LOI with its clinical utility. Finally, several aggregation methods that represent commonly used human decision-making strategies are considered and evaluated for their suitability in a CDSS. Four aggregation measures (Average, Bayes, Adjusted Bayes, and WMLO) are evaluated, that offer a compromise between two common decision making paradigms: conservativeness (average) and extremeness (Bayes).
Standard classification methods have high specificity at a cost of poor sensitivity at low levels of disease involvement, but tend to improve with disease progression. The hierarchical model is able to provide a better balance between low-LOI sensitivity and specificity by providing the classifier with more concise definitions of abnormality due to LOI. Furthermore, a method for detecting two discrete levels of disease involvement (low and high) is accomplished with reasonable accuracy. The average aggregation method offers a conservative decision that is preferred when the quality of the evidence is poor or not known, while the more extreme aggregators such as Bayes rule perform optimally when the evidence is accurate, but underperform otherwise due to outlier values that are incorrect.
The methods developed offer several improvements to PMC, by providing a better balance between sensitivity and specificity, through the definition of a clinically useful and accurate measure of LOI, and by understanding conditions for which each of the aggregation measures is better suited. These developments will enhance the quality of decision support offered by QEMG techniques, thus improving the diagnosis, treatment and management of neuromuscular disorders.
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Potenciál nádraží v rámci obchodu a cestovního ruchu / The Potential of Railway Stations in Trade and TourismMALECHOVÁ, Adéla January 2016 (has links)
The diploma thesis was focused especially on train station service supplies and on the potential offered by unutilized or misused spaces of a train station hall. The main goal was to find, define and examine this potential in a chosen station within Trade and Tourism development in a chosen place. The railway station in Ceske Budejovice became the chosen train station. The thesis contains a mapping of the given place, a marketing research carried out among train passengers travelling with the Czech Railway company, as well as on social networks through an on-line survey. The secondary objective was a determination of several possible suggestions to improve the train station, out of which one main suggestion was chosen and subsequently analysed.
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Estimação de velocidade de composições usando processamento de vídeo / Speed estimation.of trains using vídeo processingEvelyn da Silva Viana 05 August 2011 (has links)
Esta dissertação tem como objetivo estudar um método para estimar a velocidade de veículos ferroviários usando processamento de vídeo. O sistema proposto consiste na utilização de câmeras ao longo das vias férreas que permitam não só o monitoramento do tráfego ferroviário, mas cujo vídeo captado possa ser utilizado para a obtenção de estimativas para a velocidade instantânea dos trens que por ela trafegam. Tal sistema seria utilizado independentemente dos sistemas de controle já utilizados pela operadora do sistema ferroviário, permitindo que os controladores possam ter uma segunda análise no caso de falha da primeira, assim como um modelo que permita avaliar a velocidade instantânea do veículo ferroviário ao longo do percurso. Os algoritmos de rastreamento empregados para esse fim abordaram diferentes métodos. Confrontaram-se os resultados obtidos com os algoritmos propostos com os dados empíricos de forma a determinar aquele com melhor resposta dada as características do sistema. O algoritmo que apresentou os melhores resultados emprega um único bloco de referência para todos os quadros comparados. A métrica de similaridade responsável por determinar quais blocos são mais ou menos similares dentro do universo de busca estipulado é a soma de diferenças absolutas (SAD, Sum of Absolute Differences). O tempo de processamento requerido por cada um dos métodos de rastreamento estudados também foi considerado nas avaliações de resultados apresentadas. Uma comparação realizada entre as velocidades coletadas e aquelas informadas pelo sistema de controle mostraram que os resultados obtidos com o sistema atual, utilizando a sinalização apenas por circuito de via apresenta resultados pouco confiáveis com erros bastante significativos. Os resultados obtidos com o sistema proposto apresentaram erros menores quando comparados àqueles obtidos pelo sistema vigente, apresentando-se assim como uma solução viável e de baixo custo quando comparada às técnicas atualmente empregadas para a medida de velocidade de trens. / This dissertation aims to study a method of estimating the speed of railway vehicles using video processing. The proposed system uses cameras disposed alongside railways to monitor traffic as well as estimate train speeds. Such a system would allow the machinist to have a backup control system, regardless of the control systems already used by the operator of the rail system. In this dissertation, tracking algorithms with different methods are discussed. By comparing results obtained with the proposed algorithm and results from empirical data, it was possible to determine the one that best provided the desired results given the characteristics of the system. The algorithm which presented the best results was the one that employs a single block for all reference frames compared. The metric of similarity used for determining which blocks are most similar within the searched universe is the sum of absolute differences (SAD). The processing time required by each of the screening methods studied was also considered in assessing the results presented. A comparison between the rates collected and those informed by the control system showed that the results obtained with the current system, which only uses the signal track circuit, provides unreliable results with very significant errors. The results obtained with the proposed system had errors smaller than those obtained with the current system, suggesting the proposed system is viable and cost-effective compared to currently employed techniques.
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Estimação de velocidade de composições usando processamento de vídeo / Speed estimation.of trains using vídeo processingEvelyn da Silva Viana 05 August 2011 (has links)
Esta dissertação tem como objetivo estudar um método para estimar a velocidade de veículos ferroviários usando processamento de vídeo. O sistema proposto consiste na utilização de câmeras ao longo das vias férreas que permitam não só o monitoramento do tráfego ferroviário, mas cujo vídeo captado possa ser utilizado para a obtenção de estimativas para a velocidade instantânea dos trens que por ela trafegam. Tal sistema seria utilizado independentemente dos sistemas de controle já utilizados pela operadora do sistema ferroviário, permitindo que os controladores possam ter uma segunda análise no caso de falha da primeira, assim como um modelo que permita avaliar a velocidade instantânea do veículo ferroviário ao longo do percurso. Os algoritmos de rastreamento empregados para esse fim abordaram diferentes métodos. Confrontaram-se os resultados obtidos com os algoritmos propostos com os dados empíricos de forma a determinar aquele com melhor resposta dada as características do sistema. O algoritmo que apresentou os melhores resultados emprega um único bloco de referência para todos os quadros comparados. A métrica de similaridade responsável por determinar quais blocos são mais ou menos similares dentro do universo de busca estipulado é a soma de diferenças absolutas (SAD, Sum of Absolute Differences). O tempo de processamento requerido por cada um dos métodos de rastreamento estudados também foi considerado nas avaliações de resultados apresentadas. Uma comparação realizada entre as velocidades coletadas e aquelas informadas pelo sistema de controle mostraram que os resultados obtidos com o sistema atual, utilizando a sinalização apenas por circuito de via apresenta resultados pouco confiáveis com erros bastante significativos. Os resultados obtidos com o sistema proposto apresentaram erros menores quando comparados àqueles obtidos pelo sistema vigente, apresentando-se assim como uma solução viável e de baixo custo quando comparada às técnicas atualmente empregadas para a medida de velocidade de trens. / This dissertation aims to study a method of estimating the speed of railway vehicles using video processing. The proposed system uses cameras disposed alongside railways to monitor traffic as well as estimate train speeds. Such a system would allow the machinist to have a backup control system, regardless of the control systems already used by the operator of the rail system. In this dissertation, tracking algorithms with different methods are discussed. By comparing results obtained with the proposed algorithm and results from empirical data, it was possible to determine the one that best provided the desired results given the characteristics of the system. The algorithm which presented the best results was the one that employs a single block for all reference frames compared. The metric of similarity used for determining which blocks are most similar within the searched universe is the sum of absolute differences (SAD). The processing time required by each of the screening methods studied was also considered in assessing the results presented. A comparison between the rates collected and those informed by the control system showed that the results obtained with the current system, which only uses the signal track circuit, provides unreliable results with very significant errors. The results obtained with the proposed system had errors smaller than those obtained with the current system, suggesting the proposed system is viable and cost-effective compared to currently employed techniques.
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Transporte e exclusão social: a mobilidade da população de baixa renda da Região Metropolitana de São Paulo e trem metropolitano / Transportation and social exclusion: the mobility of low income population of São Paulo metropolitan region and metropolitan train.Silvio José Rosa 12 September 2006 (has links)
A Região Metropolitana de São Paulo (RMSP) com mais de 18 milhões de habitantes realizando por dia 39 milhões de viagens, sendo 25 milhões motorizadas e 14 milhões a pé, convive com problemas diários que dificultam os deslocamentos necessários da sua população. O crescimento desordenado da região exigiu mais e maiores deslocamentos, contribuindo para deteriorar a qualidade do transporte coletivo. Os indivíduos, insatisfeitos com essa condição, buscaram suprir suas necessidades de transporte, invariavelmente, com o uso do automóvel (os que podem), o que aumenta a dependência por esse modo e contribui para a inviabilidade do transporte público segregando espacialmente os mais pobres. Assim, temos a caracterização de uma forma de exclusão social proporcionada pela insuficiência dos meios de transportes na RMSP, que pode se agravar à medida que o custo financeiro crescente do deslocamento em função da distância, transbordos tarifados etc., atinja diretamente os usuários de menores rendas. Há uma associação muito estreita entre mobilidade urbana e renda, ou seja, a renda familiar é um fator determinante da mobilidade. Diante disto, este trabalho tem como objetivo analisar a mobilidade da população de baixa renda da Região Metropolitana de São Paulo (RMSP), usuária do Trem Metropolitano. Esta analise se dará pela comparação dos dados das pesquisas Origem e Destino de 1997, realizada pela Companhia do Metropolitano de São Paulo (CMSP), e a de Acesso e Difusão de 2005, realizada pela Companhia Paulista de Trens Metropolitanos (CPTM). Desta forma, busca-se entender os padrões de viagens da população de baixa renda estudada, em face das suas limitações de renda e da eventual segregação espacial e, posteriormente, diante dos resultados obtidos, propor programas de Gerenciamento da Mobilidade, que potencializem a sua mobilidade. / The São Paulo Metropolitan Region (RMSP) with more than 18 million inhabitants carrying through per day 39 millions trips, shared in 25 millions motorized and 14 millions walking, coexists daily problems that make it difficult the necessary displacements of its population. The disordered growth of the region demanded more and bigger displacements contributing to decrease the quality of the collective transport. The individuals, unsatisfied with this condition, had searched to supply its transportation necessities, invariably, with the use of the automobile (the ones that can), what it increases the dependence for this way and contributes for the unfeasibility of the public transport, propelling the poorer to a spatial segregation. Thus, we have the characterization of a form of proportionate social exclusion for the insufficience of the transports modes in the RMSP that can be aggravated to the measure that the increasing financial cost of the displacement in function of the distance, cost modes transferences etc., and directly reaches the users of lesser incomes. It has a very narrow association between urban mobility and income, that is, the familiar income is a determinative factor of mobility. Ahead of this, this work has as objective to analyze the mobility of the low income population of the São Paulo Metropolitan Region (RMSP), user of the Metropolitan Train. This analyzes will give for the comparison of the data of the research Origin and Destination of 1997, carried through for the Company of the Metropolitan of São Paulo (CMSP), and of Access and the Diffusion of 2005, carried through for the São Paulo Company of Metropolitan Trains (CPTM). In such a way, one searchs to understand the standards of trips of the studied low income population, in face of its limitations of income and eventual spatial segregation e, later, ahead of the overcome, to consider programs of Management of Mobility, that improve its mobility.
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Gerenciamento da confiabilidade em projetos de material rodante ferroviário. / Management of reliability in railway rolling stock designs.Alexandre Facini dos Santos 11 September 2007 (has links)
É cada vez maior a demanda pela eficiência dos sistemas ferroviários. A confiabilidade do material rodante é um dos fatores de desempenho mais importantes para a eficiência global dos trens de passageiros. Para que índices satisfatórios de confiabilidade, disponibilidade, mantenabilidade e segurança (CDMS) sejam alcançados, deve-se considerar esses fatores desde a elaboração da especificação técnica do material rodante até a operação da frota, incluindo projeto, fabricação, testes, comissionamento e garantia. No presente trabalho foram pesquisados os principais requisitos, normas e boas práticas empregadas na indústria ferroviária mundial para o gerenciamento da confiabilidade em projetos de material rodante, levando-se em conta os aspectos práticos e científicos. Para isso, foram inicialmente apresentadas algumas especificidades do setor ferroviário assim como alguns dos principais tipos de veículos ferroviários e seus sistemas, para que se tenha uma visão geral do contexto em que o trabalho está inserido. Em relação ao gerenciamento de CDMS propriamente dito, são mencionadas as principais tarefas a serem realizadas, de acordo com as referências consultadas. Foi dada uma atenção especial às especificações técnicas de CDMS, levando-se em conta a classificação das falhas e a determinação de parâmetros contratuais. Também foram abordados os aspectos teóricos e práticos das principais ferramentas e métodos de análise de CDMS empregados, tais como alocação de metas, predição de confiabilidade, diagrama de blocos, FMECA, FTA, monitoramento da confiabilidade em campo, etc. / Demand for efficiency in railway systems is increasing through the years. Rolling stock reliability is one of the most important performance factors for the global efficiency of passenger trains. To attain satisfactory reliability, availability, maintainability and safety (RAMS) figures, these factors must be considered from the elaboration of rolling stock technical specifications up to the operation of the fleet, including design, manufacturing, tests, commissioning and warranty. In the present work a research on main requirements, standards and good practices applied in worldwide railway industry for managing reliability in rolling stock designs was carried out, taking into account practical and scientific aspects. Some specificities of railway industry as well as some of the main railway vehicles types and related systems were presented, so that one can have an overview of the context where this work is inserted. Related to RAMS management, the main tasks to be done are presented, according to the references. Special attention was paid to RAMS technical specifications, considering failure classifications and determination of contractual parameters. The theoretical and practical aspects of the main tools and analysis methods of RAMS applied to the rolling stock design, such as apportionment of targets, reliability predictions, reliability block diagrams, FMECA, FTA, monitoring of field reliability, etc., were also covered.
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Aplicação de modelos de estimação de fitness em algoritmos geneticos / Fitness estimation models applied to genetic algorithmsMota Filho, Francisco Osvaldo Mendes 21 December 2005 (has links)
Orientador: Fernando Antonio Campos Gomide / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-05T20:02:48Z (GMT). No. of bitstreams: 1
MotaFilho_FranciscoOsvaldoMendes_M.pdf: 2700152 bytes, checksum: 3ab58e91f1a3839dae9d39e47d33ff50 (MD5)
Previous issue date: 2005 / Resumo: Para obter uma solução satisfatória, algoritmos genéticos avaliam, em geral, um número grande de indivíduos durante o processo evolutivo. É comum, em aplicações práticas, encontrar funções de avaliação computacionalmente complexas e caras. Porém, nesses casos, o tempo é um fator determinante no desempenho de algoritmos genéticos. Dessa forma, os algoritmos genéticos devem encontrar soluções adequadas em curto intervalo de tempo. Uma alternativa promissora para contornar os custos computacionais referentes à função de avaliação considera o fato de que pode ser mais atrativo avaliar diretamente somente indivíduos selecionados e estimar os fitness dos restantes do que avaliar diretamente toda a população. Este trabalho propõe o uso de modelos de estimação de fitness em algoritmos genéticos. Especificamente, são sugeridos modelos de estimação baseados em agrupamento nebuloso supervisionado (Fuzzy C-Means) e não supervisionado (Aprendizagem Participativa). O objetivo é aproximar as funções de avaliação por meio de modelos de estimação de fitness, sem afetar significativamente a qualidade das soluções. Inicialmente, os modelos de estimação propostos são comparados e analisados experimentalmente com alternativas sugeri das por outros autores, utilizando, para isso, problemas de otimização considerados na literatura de algoritmos genéticos. A seguir, os modelos de estimação de fitness são aplicados em um problema real de engenharia, o planejamento de circulação de trens em ferrovias. Este é um caso típico onde o desempenho de cada planejamento exige um tempo significativo. A eficiência dos modelos propostos é verificada e comprovada experimentalmente comparando com os resultados, em instâncias mais simples, fornecidos por modelos de programação matemática e, em instâncias complexas, fornecidos pelo algoritmo genético clássico / Abstract: Genetic algorithms usually need a large number of fitness evaluations before a satisfying result can be obtained. In many real-world applications, fitness evaluation may be computationally complex and costly. In these cases, time is an essential subject in performance analysis of genetic algorithms. Therefore, genetic algorithms should provide good solutions in a short period of time. A promising approach to alleviate the computational cost of evaluations considers the fact that sometimes it is better to evaluate only selected individuals and estimate the fitness of the remaining individuals instead of evaluate a whole population. This work suggests the application of fitness estimation models in genetic algorithms. More specifically, it deals with estimation models based on supervised fuzzy clustering (Fuzzy C-Means) and unsupervised fuzzy clustering (Participatory Learning). The goal is to approximate the evaluation
functions through the use of fitness estimation models, without significantly affect the quality of solutions. Initially, the fitness estimation models are compared and analyzed experimentally with other models already proposed in the literature. Their performance are evaluated using benchmark optimization problems found in the genetic algorithms literature. Next, the fitness estimation models are used to solve a real-world engineering problem, namely the train scheduling in a freight rail line. This is a typical case where the performance measure of each schedule demands a considerable amount of time. Once again, the performance of the fitness estimation models are evaluated experimentally, comparing their results with the results provided, for simple instances, by linear programming models and, for complex instances, by the classic genetic algorithm / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica
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