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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.
141

Estudo psicofísico sobre conspicuidade, estética e harmonia ambiental de sinais de trânsito / Psychophysics study on conspicuity, aesthetics and urban environment harmony of traffic signs

Adriane Monteiro Fontana 15 December 2005 (has links)
Neste trabalho são analisadas a conspicuidade (impacto visual), a estética e a harmonia com o meio ambiente dos principais sinais verticais de trânsito na área urbana. A análise é realizada com base nas respostas de questionários aplicados a grupos de pessoas (sujeitos), utilizando o método de comparação aos pares, da psicofísica. A pesquisa se concentrou nos seguintes sinais de regulamentação: sinal vertical de parada obrigatória, sinal vertical de sentido de circulação de via, sinal vertical de lombada, e no sinal de orientação de indicação de lugares. No caso dos sinais de regulamentação foram investigadas as seguintes características: tamanho da placa, largura do suporte e cor do suporte. No sinal de indicação de lugares, foram investigadas a cor do fundo da placa e a cor da estrutura de sustentação. No que concerne ao sinal de parada obrigatória, a pesquisa aponta como mais indicados uma largura da placa de 80 cm, suporte com largura de 12,5 cm e cor vermelha ou branca. Quanto ao sinal de sentido de circulação de via, as características mais indicadas são: largura da placa entre 60 e 70 cm, suporte com largura de 12,5 cm e cor vermelha. Em relação a placa de lombada, as características mais indicadas são: largura da placa de 80 cm, suporte com largura de 12,5 cm e cor preta. No que diz respeito de indicação de lugares, a pesquisa aponta como mais indicadas as seguintes características: cor da placa azul (distinta da cor verde regulamentada pelo Código de Trânsito Brasileiro) e suporte de sustentação da placa de cor verde (cor regulamentada pelo código do país) na cor preta ou verde. A comparação de alguns dos resultados encontrados no trabalho com aqueles obtidos em outras pesquisas mostram grande conformidade. Cabe ressaltar, contudo, que os resultados obtidos no trabalho devem ser vistos como tendências, pois o tamanho e a estratificação das amostras não satisfazem os requisitos para que os resultados tenham confiabilidade estatística. / In this work the conspicuity (visual impact), aesthetic and the environment harmony of the main traffic signs in the urban area are analyzed. The analysis is performed based on questionnaires answers applyed the groups of people (subjects), using the psychophysics method of comparison in pairs. The research is focus in the following traffic signs: regulatory signs - stop sign, one way sign - , speed bump warning sign and guide signs. In the case of the regulatory and warning signs the next attributes had been investigated: size of the sign, width and color of the support. In guide sings, the ground color sign and structure color had been investigated. About stop sign, the research points as more indicated a sign width of 80 cm, support width of 12,5 cm and red or white color. Concerning on one way sign, the pointed out characteristics are: sign width between 60 and 70 cm, support width of 12,5 cm and red color. In relation the speed bump warning sign, the more indicated characteristics: sign width of 80 cm, support width of 12,5 cm and black color. About guide sings, the research indicates as more indicated the following featuress: blue color to the sign ground (distinct of the green sing regulated by the brazilian traffic code) and black or green color to sustentation structure of the green color sign (color regulated by country laws). The comparison of some results found in the work with those gotten in other early research shows a great conformity. Its important to highlightes, however, that the results gotten in the work must be seen as tendencies, because the sample size and stratification does not satisfy the requirements to the trustworthiness statistics results.
142

Towards visual urban scene understanding for autonomous vehicle path tracking using GPS positioning data. / Vers l'interprétation de scènes urbaines pour le suivi de trajectoires pour véhicule autonome en utilisant les positions GPS.

Gamez serna, Citlalli 29 April 2019 (has links)
Cette thèse de doctorat s’intéresse au suivi de trajectoire basé sur la perception visuelle et la localisation en milieu urbain. L'approche proposée comprend deux systèmes. Le premier concerne la perception de l'environnement. Cette tâche est effectuée en utilisant des techniques d'apprentissage profond pour extraire automatiquement les caractéristiques visuelles 2D et utiliser ces derniers pour apprendre à distinguer les différents objets dans les scénarios de conduite. Trois techniques d'apprentissage approfondi sont adoptées : la segmentation sémantique pour assigner chaque pixel d’une image à une classe, la segmentation d'instance pour identifier les instances séparées de la même classe et la classification d'image pour reconnaître davantage les étiquettes spécifiques des instances. Ici, notre système considère 15 classes d'objets et reconnaît les panneaux de signalisation. Le deuxième système fait référence au suivi de chemin numérisé. Dans un premier temps, le véhicule équipé enregistre d'abord l'itinéraire avec un système de vision stéréo et un récepteur GPS (étape d'apprentissage ou numérisation du chemin). Ensuite, le système proposé analyse hors ligne la trajectoire GPS et identifie exactement les emplacements des courbes dangereuses (brusques) et les limitation de vitesse via les données visuelles. Enfin, une fois que le véhicule est capable de se localiser lui-même durant la phase de suivi de chemin, le module de contrôle du véhicule piloté avec notre algorithme de négociation de vitesse, prend en compte les informations extraites et calcule la vitesse idéale à exécuter. Grâce aux résultats expérimentaux des deux systèmes, nous prouvons que le premier est capable de détecter et de reconnaître précisément les objets d'intérêt dans les scénarios urbains, tandis que le suivi de trajectoire réduit significativement les erreurs latérales entre le trajet appris et le trajet parcouru. Nous soutenons que la fusion des deux systèmes améliorera le suivi de chemin pour prévenir les accidents ou assurer la conduite autonome. / This PhD thesis focuses on developing a path tracking approach based on visual perception and localization in urban environments. The proposed approach comprises two systems. The first one concerns environment perception. This task is carried out using deep learning techniques to automatically extract 2D visual features and use them to learn in order to distinguish the different objects in the driving scenarios. Three deep learning techniques are adopted: semantic segmentation to assign each image pixel to a class, instance segmentation to identify separated instances of the same class and, image classification to further recognize the specific labels of the instances. Here our system segments 15 object classes and performs traffic sign recognition. The second system refers to path tracking. In order to follow a path, the equipped vehicle first travels and records the route with a stereo vision system and a GPS receiver (learning step). The proposed system analyses off-line the GPS path and identifies exactly the locations of dangerous (sharp) curves and speed limits. Later after the vehicle is able to localize itself, the vehicle control module together with our speed negotiation algorithm, takes into account the information extracted and computes the ideal speed to execute. Through experimental results of both systems, we prove that, the first one is capable to detect and recognize precisely objects of interest in urban scenarios, while the path tracking one reduces significantly the lateral errors between the learned and traveled path. We argue that the fusion of both systems will ameliorate the tracking approach for preventing accidents or implementing autonomous driving.
143

Pedestrian safety at signalized intersections operating the flashing yellow arrow

Tuss, Halston 21 September 2012 (has links)
At signalized intersections, pedestrians are considered to be amongst the most vulnerable. When in the crosswalk at intersections without protected left-turn phasing, pedestrians are particularly at risk from left-turning vehicles. Until recently, a wide variety of indications were in use across the US to indicate a permissive left-turn condition to the driver. In Oregon, the Flashing Yellow Arrow (FYA) has been used to indicate the permissive left-turn condition for approximately 10 years. With the addition of the FYA in the 2009 MUTCD, it is likely that its use will continue to increase nationally. Though many operational and safety issues have been studied about the FYA indication, this research proposes to fully investigate factors that influence driver behavior in the context of the permissive left-turn conflict with pedestrians. Specifically, the research seeks to study driver glance behavior to identify reasons why drivers are, "looking at but not seeing" pedestrians in or near the crosswalk or not searching for the presence of pedestrians at all. / Graduation date: 2013
144

The ability of elderly pedestrians to use traffic signal controlled crossroads in Hong Kong: environmental demandand other associated factors

Lo, Tak-man., 盧德敏. January 2003 (has links)
published_or_final_version / Gerontology / Master / Master of Social Sciences
145

Traffic circles in South Africa : traffic performance and driver behaviour.

Krogscheepers, Johann Christoff. January 1997 (has links)
This thesis presents the results of an investigation into traffic operations and driver behaviour at traffic circles under South African conditions. The scarcity of local traffic circles necessitated the development of a simulation program (TRACSIM) to assist in the research process. This microscopic program for single lane circles is based on event updates and was calibrated and validated based on local data. Because the acceptance of gaps is such a vital part of the operation of a traffic circle, it was examined in detail. Specific attention was given to the possible use of a gap acceptance model based on variables other than time. Since the gap acceptance process also depends on the gap distribution in the circulating stream, the effect of the origin-destination pattern was also investigated. Two existing analysis techniques are evaluated and verified for local conditions, improving them where possible. Generally these techniques under-estimate traffic delay at local circles. Observations indicate a difference between the acceptance of gaps/lags in the entering and circulating stream of conflicting traffic as well as a difference between critical gaps and critical lags. The mean observed critical gaps/lags are larger than in other countries, which indicates that delays at local circles will be greater. Gap/lag acceptance based on critical distances rather than critical times was applied successfully in the simulation program TRACSIM. A method is proposed to estimate critical distances from the geometric layout of the circle. Critical gaps are not fixed, but should vary with at least the conflicting flows. The investigation of the effect of unbalanced flows on delay, showed that the variability in drivers' critical gaps is more a function of delay than of conflicting flow. Entry delays increase because of an increase in conflicting flows or because of an unfavourable imbalance of conflicting flows. In both instances the drivers' critical gaps will decrease. A variable critical gap model only based on conflicting flows will show no change in the drivers' critical gaps if the conflicting volumes remain constant, even though the actual average delay might increase because of an unfavourable imbalance in conflicting flows. / Thesis (Ph.D.)-University of Natal, Durban, 1997.
146

An agency approach to analyze and improve a photometric device test procedure using design of experiments methodology

Ramalingam, Sivam. Simpson, James R. January 2006 (has links)
Thesis (M.S.)--Florida State University, 2006. / Advisor: James R. Simpson, Florida State University, College of Engineering, Dept. of Industrial Engineering. Title and description from dissertation home page (viewed Sept. 22, 2006). Document formatted into pages; contains ix, 95 pages. Includes bibliographical references.
147

Návrh cyklostezky v okolí obce Kamenný Újezd. / Proposal for a cycling trail in the vicinity of Kamenný Újezd village

DOBNEROVÁ, Karla January 2009 (has links)
The main objective of my thesis was to project a design of a concrete chosen section of the cycling trail in the vicinity of the village of Kamenný Újezd, which is located in Southern Bohemia, south-west of České Budějovice. I propose two alternative cycling trails in accordance with the applicable standards, laws and technical conditions. A better alternative in terms of transport, economy, ecology and aesthetics, I elaborated to the phase of documentation for the notification of the construction of road according to Decree 104/1997 Sb.. In the project, I propose a direction solution, vertical solutions, width layout, road construction, earthworks, drainage, equipment and traffic signs. I analyzed property relations in the proposed cycling route and existing bicycle trails in the given locality. I suggested a cycling communication, which is multifunctional, therefore not only used by cyclists but also pedestrians, in-line skaters, and when appropriate, for occasional agricultural transport.
148

Problematika parkování ve městě České Budějovice / The issue of parking in České Budějovice

Sezemská, Stephanie January 2019 (has links)
The Diploma thesis deals with the issue of parking in Ceske Budejovice. The basis of the work is to evaluate the transport situation in the city. The consultation will assess the critical issues, from the point of view of parking, which will be further developed by the local maintenance and measurements. As a result of the local scrutiny, measures will be proposed to help improve the current situation.
149

Posouzení svislého dopravního značení na vybraných křižovatkách / Assessment of road traffic signs on selected cross sections

Vaclík, Adam January 2014 (has links)
The aim of this thesis is to verify the accuracy of the location of the vertical road signs at selected intersections and to consider colorimetric and retroreflective properties of some of them. If some brands fail, it is necessary to propose solutions. At the end of this work there is a summary of how many brands fail and subsequent percentaual quantification.
150

Detekce a rozpoznání dopravních značek v obraze / Detection and Recognition of Traffic Signs in Image

Spáčil, Pavel January 2011 (has links)
This work focuses on classification and recognition of traffic signs in image. It describes briefly some used methods a deeply describes chosen system including extensions and method for creating models needed for classification. There's described implementation of library and demonstration program including important pieces of knowledge discovered during development. There're also results of some experiments and possible enhancements in conclusion.

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