Este trabalho visa localizar os pontos de proibição de ultrapassagem em uma rodovia, buscando conhecer e avaliar de forma prática e precisa os locais das marcações das faixas de sinalização horizontal, analisando-se um método moderno baseado nas informações dos satélites artificiais do Sistema de Posicionamento Global - GPS, e os métodos clássicos de levantamentos topográficos utilizados. Apresenta-se uma revisão dos principais conceitos relacionados ao perfil longitudinal, à distância de visibilidade nas curvas verticais e aos métodos utilizados para levantamento. Os resultados gráficos permitiram uma avaliação dos perfis e das marcações, obtendo-se um resultado satisfatório na avaliação do método moderno. / This work has the objective to locate the points of no passing lanes on a road, trying to know and evaluate in a practical and accurate way the places of horizontal signalization, analyzing a modern method based in collected information from the artificial satellites of the Global Positioning System - GPS, and classic methods of surveying. A review of the main concepts related to the longitudinal profile, of the sight distance in vertical turns, and to the methods used to surveying the graphic results permitted the evolution of profiles and marking, obtaining a satisfactory result in the evolution of the modern method.

Este trabalho visa localizar os pontos de proibição de ultrapassagem em uma rodovia, buscando conhecer e avaliar de forma prática e precisa os locais das marcações das faixas de sinalização horizontal, analisando-se um método moderno baseado nas informações dos satélites artificiais do Sistema de Posicionamento Global - GPS, e os métodos clássicos de levantamentos topográficos utilizados. Apresenta-se uma revisão dos principais conceitos relacionados ao perfil longitudinal, à distância de visibilidade nas curvas verticais e aos métodos utilizados para levantamento. Os resultados gráficos permitiram uma avaliação dos perfis e das marcações, obtendo-se um resultado satisfatório na avaliação do método moderno. / This work has the objective to locate the points of no passing lanes on a road, trying to know and evaluate in a practical and accurate way the places of horizontal signalization, analyzing a modern method based in collected information from the artificial satellites of the Global Positioning System - GPS, and classic methods of surveying. A review of the main concepts related to the longitudinal profile, of the sight distance in vertical turns, and to the methods used to surveying the graphic results permitted the evolution of profiles and marking, obtaining a satisfactory result in the evolution of the modern method.

The purpose of this study was to examine conditions under which functional ability predicts relocation of older persons. Data for this study came from a sample of 6,225 respondents aged 70 or older, who were interviewed both at Wave 1 (1993) and 2 (1995) of a longitudinal national survey of Asset and Health Dynamics Among the Oldest Old (AHEAD). Hierarchical logistic regression analyses were used to estimate the effects of functional ability, functional ability and assistance from human resources, and functional ability and built-environment features on the probability of relocation when socio-demographic variables were controlled. Important findings are, first, differences in functional ability differentially predict future relocation behavior of older persons and, second, the existence of built-environment features in a residence has a reducing effect on the probability of entrance into an institutional setting in conjunction with functional difficulty. Household ADL decline between 1993 and 1995, as well as advanced ADL (i.e., cognitive ADL) and lower body activity difficulty in 1993, were predictors of the increased probability of residential moves occurred over the same period. Basic, household, and advanced ADL decline between 1993 and 1995, as well as basic, household, advanced ADL, and lower body activity difficulty in 1993, were predictors of the increased probability of entrances into an institutional setting occurred over the same period. Older persons who lived in a residence with built-environment features in 1993 were less likely to enter an institutional setting when they experienced basic ADL or lower body activity declines between 1993 and 1995. The onset of LBA and/or AADL difficulty triggered residential moves. Efforts to enhance the independent living of older persons in the community setting should target the compensation of LBA and/or AADL difficulty. / Graduation date: 2001

Data showing a trend that characterizes a change due to a shock to the system are a type of changepoint data, and may be referred to as shock-through data. As a result of the shock, this type of data may exhibit one of two types of transitions: gradual or abrupt. Although shock-through data are of particular interest in many areas of study such as biological, medical, health and environmental applications, previous research has shown that statistical inference from modeling the trend is challenging in the presence of discontinuous derivatives. Further complications arise when we have (1) longitudinal data, and/or (2) samples which come from two potential populations: one with a gradual transition, and the other abrupt. Bent-cable regression is an appealing statistical tool to model shock-through data due to the model's flexibility while being parsimonious with greatly interpretable regression coefficients. It comprises two linear segments (incoming and outgoing) joined by a quadratic bend. In this thesis, we develop extended bent-cable methodology for longitudinal data in a Bayesian framework to account for both types of transitions; inference for the transition type is driven by the data rather than a presumption about the nature of the transition. We describe explicitly the computationally intensive Bayesian implementation of the methodology. Moreover, we describe modeling only one type of transition, which is a special case of this more general model. We demonstrate our methodology by a simulation study, and with two applications: (1) assessing the transition to early hypothermia in a rat model, and (2) understanding CFC-11 trends monitored globally. Our methodology can be further extended at the cost of both theoretical and computational extensiveness. For example, we assume that the two populations mentioned above share common intercept and slopes in the incoming and outgoing phases, an assumption that can be relaxed for instances when intercept and slope parameters could behave differently between populations. In addition to this, we discuss several other directions for future research out of the proposed methodology presented in this thesis.

Data showing a trend that characterizes a change due to a shock to the system are a type of changepoint data, and may be referred to as shock-through data. As a result of the shock, this type of data may exhibit one of two types of transitions: gradual or abrupt. Although shock-through data are of particular interest in many areas of study such as biological, medical, health and environmental applications, previous research has shown that statistical inference from modeling the trend is challenging in the presence of discontinuous derivatives. Further complications arise when we have (1) longitudinal data, and/or (2) samples which come from two potential populations: one with a gradual transition, and the other abrupt. Bent-cable regression is an appealing statistical tool to model shock-through data due to the model's flexibility while being parsimonious with greatly interpretable regression coefficients. It comprises two linear segments (incoming and outgoing) joined by a quadratic bend. In this thesis, we develop extended bent-cable methodology for longitudinal data in a Bayesian framework to account for both types of transitions; inference for the transition type is driven by the data rather than a presumption about the nature of the transition. We describe explicitly the computationally intensive Bayesian implementation of the methodology. Moreover, we describe modeling only one type of transition, which is a special case of this more general model. We demonstrate our methodology by a simulation study, and with two applications: (1) assessing the transition to early hypothermia in a rat model, and (2) understanding CFC-11 trends monitored globally. Our methodology can be further extended at the cost of both theoretical and computational extensiveness. For example, we assume that the two populations mentioned above share common intercept and slopes in the incoming and outgoing phases, an assumption that can be relaxed for instances when intercept and slope parameters could behave differently between populations. In addition to this, we discuss several other directions for future research out of the proposed methodology presented in this thesis.

published_or_final_version / Medicine / Master / Doctor of Medicine

No description available.

No description available.

published_or_final_version / Statistics and Actuarial Science / Doctoral / Doctor of Philosophy

In this report, I study familial longitudinal count data with a Poisson regression model. The data is collected from individuals who are nested in families. I focus on two main issues to fit a model. The first one is the large number of excess zeros and the second one is multi-level random effects. My approach for solving these problems are to use either Zero Inflated Poisson (ZIP) or Negative Binomial (NB) models to control for the excess zeros which allow for estimation of another parameter for over dispersion while developing the model with individual and familial random effects. First, I use a Poisson regression model with only main effects. After that, I fit a ZIP model to control for the extra zeros. I provide information about general form of the exponential families and a discussion about the dispersion parameter. I also fit a Negative Binomial model instead of the ZIP model. I also build these models with only individual random effects and with both individual and familial random effects as well. I discuss the generalized estimating equation (GEE) approach to estimate the parameters of a generalized linear model with auto regressive correlation between outcomes. / text