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Reconstructing a 3-dimensional scene from a set of2-dimensional images is a fundamental problem in computervision. A system capable of performing this task can be used inmany applications in robotics, architecture, archaeology,biometrics, human computer interaction and the movie andentertainment industry. Most existing reconstruction approaches exploit one sourceof information to tackle the problem. This is the motion of thecamera, the 2D images are taken from different viewpoints. Weexploit an additional information source, the reference plane,which makes it possible to reconstruct difficult scenes whereother methods fail. A real scene plane may serve as thereference plane. Furthermore, there are many alternativetechniques to obtain virtual reference planes. For instance,orthogonal directions in the scene provide a virtual referenceplane, the plane at infinity, or images taken with a parallelprojection camera. A collection of known and novel referenceplane scenarios is presented in this thesis. The main contribution of the thesis is a novel multi-viewreconstruction approach using a reference plane. The techniqueis applicable to three different feature types, points, linesand planes. The novelty of our approach is that all cameras andall features (off the reference plane) are reconstructedsimultaneously from a single linear system of imagemeasurements. It is based on the novel observation that camerasand features have a linear relationship if a reference plane isknown. In the absence of a reference plane, this relationshipis non-linear. Thus many previousmethods must reconstructfeatures and cameras sequentially. Another class of methods,popular in the literature, is factorization, but, in contrastto our approach, this has the serious practical drawback thatall features are required to be visible in all views. Extensiveexperiments show that our approach is superior to allpreviously suggested reference plane and non-reference planemethods for difficult reference plane scenarios. Furthermore, the thesis studies scenes which do not have aunique reconstruction, so-called critical configurations. It isproven that in the presence of a reference plane the set ofcritical configurations is small. Finally, the thesis introduces a complete, automaticmulti-view reconstruction system based on the reference planeapproach. The input data is a set of images and the output a 3Dpoint reconstruction together with the correspondingcameras.

<p>Reconstructing a 3-dimensional scene from a set of2-dimensional images is a fundamental problem in computervision. A system capable of performing this task can be used inmany applications in robotics, architecture, archaeology,biometrics, human computer interaction and the movie andentertainment industry.</p><p>Most existing reconstruction approaches exploit one sourceof information to tackle the problem. This is the motion of thecamera, the 2D images are taken from different viewpoints. Weexploit an additional information source, the reference plane,which makes it possible to reconstruct difficult scenes whereother methods fail. A real scene plane may serve as thereference plane. Furthermore, there are many alternativetechniques to obtain virtual reference planes. For instance,orthogonal directions in the scene provide a virtual referenceplane, the plane at infinity, or images taken with a parallelprojection camera. A collection of known and novel referenceplane scenarios is presented in this thesis.</p><p>The main contribution of the thesis is a novel multi-viewreconstruction approach using a reference plane. The techniqueis applicable to three different feature types, points, linesand planes. The novelty of our approach is that all cameras andall features (off the reference plane) are reconstructedsimultaneously from a single linear system of imagemeasurements. It is based on the novel observation that camerasand features have a linear relationship if a reference plane isknown. In the absence of a reference plane, this relationshipis non-linear. Thus many previousmethods must reconstructfeatures and cameras sequentially. Another class of methods,popular in the literature, is factorization, but, in contrastto our approach, this has the serious practical drawback thatall features are required to be visible in all views. Extensiveexperiments show that our approach is superior to allpreviously suggested reference plane and non-reference planemethods for difficult reference plane scenarios.</p><p>Furthermore, the thesis studies scenes which do not have aunique reconstruction, so-called critical configurations. It isproven that in the presence of a reference plane the set ofcritical configurations is small.</p><p>Finally, the thesis introduces a complete, automaticmulti-view reconstruction system based on the reference planeapproach. The input data is a set of images and the output a 3Dpoint reconstruction together with the correspondingcameras.</p>

The conventional methods of determining the Origin-Destination (O-D) trip tables involve elaborate surveys, such as home interviews, requiring considerable time, manpower and funds. To overcome this drawback, a number of theoretical models that synthesize O-D trip tables from link volume data have been developed in the past. The focus of this research was on two of these models, namely, The Highway Emulator (THE) and the Linear Programming (LP) models. These models use target/seed tables for guiding the modeled trip tables. In an earlier research effort conducted by Virginia Tech Center for Transportation Research, potential was noted for enhancing these models' performances by using a superior target/seed table. This research study exploits the readily available socio-economic/census data and link volume information and proposes a methodology for obtaining improved target/seed tables, by performing the trip generation and trip distribution steps. This table was provided as target to THE and LP models, and their performances evaluated using Pulaski town as case study. In addition to measuring the closeness of the output tables to surveyed tables and their capability to replicate observed volumes, their improvements over the case when a structural table is used as target was also studied. Tests showed that the use of the superior target/seed table significantly improved the performance of the LP model. However, for THE, mixed trends are seen in terms of different measures of closeness. The sensitivity of the user parameter to place certain degree of belief on the target/seed table for LP model was also analyzed. / Master of Science

Este estudo mensurou os efeitos potenciais do balanceamento de atividades (em especial entre emprego e residência) sobre o tráfego em termos de velocidade média, veículos-quilômetro (VKM) e veículos-hora viajados(VHR), tendo como pano de fundo a Região Metropolitana de São Paulo. Foi verificada a viabilidade da aplicação de processo sintético a modelos integrados de uso do solo e transporte, contudo algumas dificuldades impossibilitaram sua aplicação dentro do prazo disponível. Foram então identificados modelos tradicionais, bem como modelos integrados de uso do solo e transportes já implementados na região e o recente estudo do Metrô – Companhia do Metropolitano de São Paulo foi definido como fonte de parâmetros e modelos para a aplicação proposta de políticas de balanceamento. Foram criados quatro cenários básicos de balanceamento entre emprego e residência a serem comparados com um cenário base representando da forma mais acurada possível a demanda de tráfego em 1997. Dois cenários se basearam na redistribuição espacial de população, mantendo-se fixa a distribuição de empregos do cenário original. Outros dois basearam-se na redistribuição de empregos com a manutenção da distribuição da população. Quatro cenários adicionais foram propostos para verificar os efeitos do balanceamento aplicado à área restrita ou a um dado nível de renda. A redistribuição integral de população apresentou melhores resultados, notadamente a redução potencial de mais de 33% de VHT e de em torno de 9% de VKT. Nem todos os resultados das redistribuições de empregos foram tão positivos, embora se tenha verificado a redução de VHT nestes cenários. Além disso, os resultados não apresentaram tendência linear, requerendo maior esforço quanto maior o nível de benefícios desejado através do balanceamento. / The present study measured the potential effects of the activity-balancing (particularly jobs and housing) on the traffic in terms of average speed, vehiclekilometer (VKT) and vehicle-hour traveled (VHT) in the Metropolitan Region of São Paulo City. It verified that using a synthesized process applied to an integrated land use and transportation model is feasible. Nevertheless, it was not possible to implement the application due to some difficulties and the time limit. Traditional and integrated models applied to the area were then identified, and the recent study of the Metrô – the Subway Company of São Paulo, which was based upon a broad Origin-Destination survey, was chosen as source of models and parameters for the jobs-housing balance policy application. Four jobs-housing balance scenarios were proposed and compared with a basic one, representing the existing transportation demand for 1997 as close as possible. Two scenarios were based on the population r edistribution based on the fixed original employment distribution. Two other were based on the redistribution of jobs with a fixed population distribution. Four additional scenarios were proposed in order to identify the effects of jobs-housing balance applied to specific area or population income level. The best results achieved were found for the population redistribution, remarkably full redistribution would potentially reduce VKT by over 33% and VHT by around 9%. Not all the results generated by the employment redistribution were good although VHT decreased in both scenarios. In addition, it was noticed that the effects are not linearly related to the balancing achieved, gradually diminishing the more balancing is reached.

Este estudo mensurou os efeitos potenciais do balanceamento de atividades (em especial entre emprego e residência) sobre o tráfego em termos de velocidade média, veículos-quilômetro (VKM) e veículos-hora viajados(VHR), tendo como pano de fundo a Região Metropolitana de São Paulo. Foi verificada a viabilidade da aplicação de processo sintético a modelos integrados de uso do solo e transporte, contudo algumas dificuldades impossibilitaram sua aplicação dentro do prazo disponível. Foram então identificados modelos tradicionais, bem como modelos integrados de uso do solo e transportes já implementados na região e o recente estudo do Metrô – Companhia do Metropolitano de São Paulo foi definido como fonte de parâmetros e modelos para a aplicação proposta de políticas de balanceamento. Foram criados quatro cenários básicos de balanceamento entre emprego e residência a serem comparados com um cenário base representando da forma mais acurada possível a demanda de tráfego em 1997. Dois cenários se basearam na redistribuição espacial de população, mantendo-se fixa a distribuição de empregos do cenário original. Outros dois basearam-se na redistribuição de empregos com a manutenção da distribuição da população. Quatro cenários adicionais foram propostos para verificar os efeitos do balanceamento aplicado à área restrita ou a um dado nível de renda. A redistribuição integral de população apresentou melhores resultados, notadamente a redução potencial de mais de 33% de VHT e de em torno de 9% de VKT. Nem todos os resultados das redistribuições de empregos foram tão positivos, embora se tenha verificado a redução de VHT nestes cenários. Além disso, os resultados não apresentaram tendência linear, requerendo maior esforço quanto maior o nível de benefícios desejado através do balanceamento. / The present study measured the potential effects of the activity-balancing (particularly jobs and housing) on the traffic in terms of average speed, vehiclekilometer (VKT) and vehicle-hour traveled (VHT) in the Metropolitan Region of São Paulo City. It verified that using a synthesized process applied to an integrated land use and transportation model is feasible. Nevertheless, it was not possible to implement the application due to some difficulties and the time limit. Traditional and integrated models applied to the area were then identified, and the recent study of the Metrô – the Subway Company of São Paulo, which was based upon a broad Origin-Destination survey, was chosen as source of models and parameters for the jobs-housing balance policy application. Four jobs-housing balance scenarios were proposed and compared with a basic one, representing the existing transportation demand for 1997 as close as possible. Two scenarios were based on the population r edistribution based on the fixed original employment distribution. Two other were based on the redistribution of jobs with a fixed population distribution. Four additional scenarios were proposed in order to identify the effects of jobs-housing balance applied to specific area or population income level. The best results achieved were found for the population redistribution, remarkably full redistribution would potentially reduce VKT by over 33% and VHT by around 9%. Not all the results generated by the employment redistribution were good although VHT decreased in both scenarios. In addition, it was noticed that the effects are not linearly related to the balancing achieved, gradually diminishing the more balancing is reached.

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