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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.
41

Utilização do sistema de posicionamento global para monitoramento de transporte fretado / Monitoring charter bus service using global positioning system

Silva, Camila Maria de Paiva e 22 December 2006 (has links)
Orientador: Maria Teresa Françoso / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T02:35:13Z (GMT). No. of bitstreams: 1 Silva_CamilaMariadePaivae_M.pdf: 5263797 bytes, checksum: 09760343e8c6a05923be7cf27642b699 (MD5) Previous issue date: 2006 / Resumo: Este trabalho visa destacar as vantagens e os pontos que devem ser tratados em um sistema AVL (Automatic Vehicle Location), baseado nas tecnologias de posicionamento por satélites e transmissão de dados via rede de telefonia móvel, quando aplicado ao transporte coletivo por fretamento. Neste sentido, três linhas de ônibus fretado que atendem funcionários da Universidade Estadual de Campinas foram monitorados por um período de 07 semanas no trajeto bairro-universidade. O módulo de rastreamento possibilitou a coleta eletrônica de dados de operação do veículo. Também foram registrados, manual e eletronicamente, informações sobre os usuários do serviço. Os dados coletados foram transmitidos via GPRS (General Packet Radio Service) para a central de controle e disponibilizados na rede mundial de computadores em tempo real. Foram verificados os pontos de parada e os itinerários e foi feita uma análise financeira das linhas de fretamento da Unicamp monitoradas durante a pesquisa. O monitoramento de transporte coletivo fretado, relatado neste trabalho de maneira provavelmente inédita, possibilitou a obtenção de dados para gerência e controle do serviço de fretamento. Observou-se, como esperado, que o sistema permite de maneira eficiente o acompanhamento da operação com registro de posições e velocidades desenvolvidas pelo veículo monitorado e dos locais de parada e itinerários cumpridos. No caso em questão, entre as vantagens obtidas destaca-se a possibilidade de realizar uma fiscalização mais efetiva, tanto pela operadora do transporte, como pela universidade, controlando os horários programados, os itinerários e os passageiros. São apresentadas sugestões para melhoria do sistema de rastreamento utilizado / Abstract: This research aims to point out the advantages and what still needs to be improved in an Automatic Vehicle Location ¿ AVL - system applied to the charter bus service. The sample of three charter bus lines serving Campinas University (Unicamp)¿s workers on their way from home to office, in a seven weak period. The AVL equipment was used to collect electronic operational data. Users information were collected automatically and manually. These data were sent through GPRS (General Packet Radio Service) to the control station and become available in the internet in real time. The itinerary and the bus stops were verified, and a financial analysis of these three lines were made. This could conclude that the system allows monitoring vehicle position and speed, bus stops, traffic points, etc. - supplying data for management and control of the service. It has showed that AVL, when applied in the Unicamp¿s fleet, support better management and control of routes and timetables. In this work it is also proposed improvements in the equipment that has been used. / Mestrado / Transportes / Mestre em Engenharia Civil
42

Kalman Filter Estimation Of Ionospheric TEC And Differential Instrumental Biases Over Low Latitude Using Dual Frequency GPS Observations

Anand Raj, R 03 1900 (has links)
The low latitude tropical ionosphere has been investigated by various researchers using Global Positioning System (GPS). Presently for many civil aviation applications, the ionospheric modeling of the tropical region has gained importance, in particular for flight safety. Since ionosphere is dispersive in nature, dual frequency (L1 = 1575.42 MHz and L2 = 1227.60 MHz) GPS observations can be used to obtain Ionospheric Total Electron Content (TEC). Since TEC varies with local time and geomagnetic latitude, an Ionospheric Modeling Technique using spatial linear approximation of vertical TEC over receiver station has been implemented following Sardon et al. The effects of all the systematic errors due to the satellite plus the receiver (SPR) instrumental biases can reach upto several nanoseconds. (1 TEC is 1016 electrons/m2, 1 ns = 2.86 TEC and 1 TEC = 0.16 m). Hence, to have an accurate estimation of ionospheric TEC, the instrumental biases must also be estimated. This thesis describes a heuristic adaptive Kalman Filtering scheme developed to estimate the TEC, the constants in the linearisation scheme, as well as the above total instrumental biases. The Kalman filter implementation is basically an optimization problem of minimizing the Cost Function J based on the difference between the model output and the measurement, called as the ‘innovation’, scaled by its covariance. In order to obtain the best possible results using the Kalman Filter approach, it is essential to provide appropriate values for the initial state, process and measurement noise covariances (P0, Q and R) respectively, which in general may not be known. Usually manual tuning of the filter parameter is carried out without using the above cost function J! The filter estimates can be highly sensitive to the above chosen statistics and thus these will have to be estimated carefully. Hence, we have utilized the Adaptive Kalman Filtering procedure of Myers and Tapley extended by Gemson and Ananthasayanam. The minimization is carried out by simultaneously estimating the above statistics and the unknown parameters, which include the TEC and the instrumental bias. In addition, A Constant Gain Kalman Filter approach using Genetic Algorithm (GA) has also been developed for the above requirement. It is observed that the steady state gains in KF and AKF approaches are in good match with the constant gains obtained from Genetic Algorithm. Using the above Adaptive Kalman Filtering technique and Constant Gain Kalman Filter approach, vertical TEC values and SPR biases have been estimated from the IGS receiver observations stationed at ISTRAC/ISRO, Bangalore, India. A diurnal TEC variation over Bangalore for a period of one year for 2003 and January 2004 is estimated and reported in this thesis. This approach has also been applied to study the behaviour of the ionosphere over low latitude IGS station at Fortaleza, Brazil data during the great magnetic storm on the 15th July 2000 and the results were found to be consistent with the results of Basu et al. In addition, Using Constant Kalman filter, the TEC enhancement over Indian region has been estimated for the October 2003 Ionospheric storm, and the results were found to be consistent with the reported results in the literature.
43

Intelligent Methods For Dynamic Analysis And Navigation Of Autonomous Land Vehicles

Kaygisiz, Huseyin Burak 01 July 2004 (has links) (PDF)
Autonomous land vehicles (ALVs) have received considerable attention after their introduction into military and commercial applications. ALVs still stand as a challenging research topic. One of the main problems arising in ALV operations is the navigation accuracy while the other is the dynamic effects of road irregularities which may prevent the vehicle and its cargo to function properly. In this thesis, we propose intelligent solutions to these two basic problems of ALV. First, an intelligent method is proposed to enhance the performance of a coupled global positioning/inertial navigation system (GPS/INS) for land navigation applications during the GPS signal loss. Our method is based on using an artificial neural network (ANN) to intelligently aid the GPS/INS coupled navigation system in the absence of GPS signals. The proposed enhanced GPS/INS is used in the dynamic environment of a tour of an autonomous van and we provide the results here. GPS/INS+ANN system performance is thus demonstrated with the land trials. Secondly, our work focuses on the identification and enlargement of the stability region of the ALV. In this thesis, the domain of attraction of the ALV is found to be patched by chaotic and regular regions with chaotic boundaries which are extracted using novel technique of cell mapping equipped with measures of fractal dimension and rough sets. All image cells in the cellular state space, with their individual fractal dimension are classified as being members of lower approximation (surely stable), upper approximation (possibly stable) or boundary region using rough set theory. The obtained rough set with fractal dimension as its attribute is used to model the uncertainty of the regular regions. This uncertainty is then smoothed by a reinforcement learning algorithm in order to enlarge regular regions that are used for chassis control, critical in ALV in preventing vibration damages that can harm the payload. Hence, we will make ALV work in the largest safe area in dynamical sense and prevent the vehicle and its cargo.
44

Σχεδιασμός loaction aware εφαρμογής σε Android

Γεωργοπούλου, Αργυρούλα 24 January 2012 (has links)
Εγχειρίδιο χρήσης της Android εφαρμογής WhatWhereWho και παρουσίαση διαδικασίας υλοποίησής της. / Manual for the Android application WhatWhereWho and description of the process needed for its implementation.
45

Avaliação do posicionamento plano-altimétrico com receptor gps em diferentes tipos de uso do solo

Itame, Otávio Yassuo [UNESP] 01 October 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-10-01Bitstream added on 2014-06-13T19:42:00Z : No. of bitstreams: 1 itame_oy_dr_botfca.pdf: 795304 bytes, checksum: f5cd4e866ab892ec4c244173b15a3d6e (MD5) / Neste trabalho, foram realizados levantamentos topográficos para a avaliação do efeito da cobertura vegetal, na recepção de sinais GPS, para obtenção de posicionamento tri-dimensional, considerando os estudos realizados em diferentes tipos de uso do solo. Vértices foram implantados em diferentes tipos de uso do solo; em área com pastagem, com plantação de seringueiras e com eucaliptos, e as suas posições determinadas com estação total, nivelamento geométrico e com receptores GPS. Na avaliação do posicionamento altimétrico adotou-se como valores de referência os desníveis determinados com o nivelamento geométrico para avaliação dos dados obtidos com receptores GPS. As coordenadas planimétricas obtidas com receptores GPS foram analisadas utilizando-se com valores de referência os dados obtidos com a estação total. No levantamento topográfico com estação total foram adotadas as prescrições estabelecidas nas Normas da Associação Brasileira de Normas Técnicas (ABNT) NBR 13.133, Execução de Levantamentos Topográficos, para poligonais do tipo IVP. Foi realizada a análise de exatidão e de precisão do posicionamento tridimensional, adotando como padrão a NBR 13133 da ABNT para a classe do levantamento executado. Para aplicações do GPS na altimetria há necessidade do conhecimento da ondulação geoidal (N), que neste trabalho, para a sua determinação foram coletados dados com receptor na referência de nível (RN). Os resultados obtidos indicam que cuidados especiais devem ser tomados nos levantamentos com receptores GPS em áreas com cobetura vegetal, pois estas interferem na propagação das ondas eletromagnéticas provenientes dos satélites podendo inviabilizar o posicionamento. / In this work, topographic surveys were carried out in order to evaluate the effect of vegetal cover, on the reception of GPS signals, for 3D positioning, considering studies to be made in different types of land use. Points were set up on different types of land use, in areas containing grass, rubber trees and eucalyptus, which had their positions defined using a total station, geometric leveling and GPS receivers In the evaluation of height positioning it was adopted as reference values the height differences determined by geometric levelling in order to evaluate data obtained through GPS receivers. Planimetric coordinates obtained by using GPS receivers were analysed using as reference values the data obtained using a total station. During the topographic survey using a total station the recommendations set up by the Brazilian Association for Technical Rules (ABNT) NBR 13.133, regarding the execution of topographic surveys, for transverses of type IVP. Accuracy and precision analysis was made on the 3D positioning, also considering ABNT NBR 13.133, for the class of topographic survey which was carried out. In order to apply GPS on height positiong it is necessary to know the geoidal ondulation (N) and, in this work, N was computed based upon data acquired employing receivers at the level reference (RN). The results obtained indicate that special care must be taken during the surveys carried out with the use of GPS receivers on areas with vegetal cover, because it causes interference in the propagation of electromagnetic waves from the satellite which can even make the positioning become unviable.
46

APPLYING UAVS TO SUPPORT THE SAFETY IN AUTONOMOUS OPERATED OPEN SURFACE MINES

Hamren, Rasmus January 2021 (has links)
Unmanned aerial vehicle (UAV) is an expanding interest in numerous industries for various applications. Increasing development of UAVs is happening worldwide, where various sensor attachments and functions are being added. The multi-function UAV can be used within areas where they have not been managed before. Because of their accessibility, cheap purchase, and easy-to-use, they replace expensive systems such as helicopters- and airplane-surveillance. UAV are also being applied into surveillance, combing object detection to video-surveillance and mobility to finding an object from the air without interfering with vehicles or humans ground. In this thesis, we solve the problem of using UAV on autonomous sites, finding an object and critical situation, support autonomous site operators with an extra safety layer from UAVs camera. After finding an object on such a site, uses GPS-coordinates from the UAV to see and place the detected object on the site onto a gridmap, leaving a coordinate-map to the operator to see where the objects are and see if the critical situation can occur. Directly under the object detection, reporting critical situations can be done because of safety-distance-circle leaving warnings if objects come to close to each other. However, the system itself only supports the operator with extra safety and warnings, leaving the operator with the choice of pressing emergency stop or not. Object detection uses You only look once (YOLO) as main object detection Neural Network (NN), mixed with edge-detection for gaining accuracy during bird-eye-views and motion-detection for supporting finding all object that is moving on-site, even if UAV cannot find all the objects on site. Result proofs that the UAV-surveillance on autonomous site is an excellent way to add extra safety on-site if the operator is out of focus or finding objects on-site before startup since the operator can fly the UAV around the site, leaving an extra-safety-layer of finding humans on-site before startup. Also, moving the UAV to a specific position, where extra safety is needed, informing the operator to limit autonomous vehicles speed around that area because of humans operation on site. The use of single object detection limits the effects but gathered object detection methods lead to a promising result while printing those objects onto a global positions system (GPS) map has proposed a new field to study. It leaves the operator with a viewable interface outside of object detection libraries.
47

Porovnání metod určování převýšení v experimentální síti Tetčice / The comparison of the method for the determination of height differencies in Tetčice experimental network

Povoda, Richard January 2012 (has links)
The subject of this thesis is comparation methods of measuring elevation of experimental points on the network site Tetčice. There was mutually comparated height differences , which were mesured with methods of precise leveling, trigonometric method and fast static GPS measurment method. It was experimentaly used Sanchez method to reduce the effects of refraction measured at zenith angles. In the area of interest was used the method of interpolation to height calculation of point Bučín in elevation system Bpv, calculated from quasi-geoid heights on the surrounding leveling points.
48

Previsão de localização futura de veículos baseada em dados de AVL. / Future location prediction of vehicles based on data AVL.

Barbosa, Luciano Aparecido 04 October 2010 (has links)
O crescente desenvolvimento de aplicações utilizadas por dispositivos móveis que fazem uso das tecnologias de posicionamento via satélite e comunicação móvel, juntamente com a popularização destes dispositivos, sejam eles celulares ou GPSs (Global Positioning System) automotivos reforçam ainda mais a necessidade de representação e o entendimento a cerca das entidades móveis retratadas nestes dispositivos e incentivam estudos que forneçam um significado maior do que a simples representação posicional destas entidades. Considera-se neste trabalho, que estas entidades móveis são veículos rastreados via satélite que fornecem sua posição espacial, determinada por um par de coordenadas geográficas (latitude e longitude), coletadas em intervalos de tempo regulares para sistemas AVL (Automatic Vehicle Location) que são responsáveis pelo monitoramento do estado destes veículos. Neste trabalho, foram desenvolvidas funções para a previsão da localização e geração de padrões dos veículos monitorados por sistemas AVL. Para tanto, as paradas efetuadas pelos veículos irão definir regiões comuns de parada ocorridas durante um intervalo de tempo passado e serão consideradas como um padrão de localização, enquanto que as trajetórias serão utilizadas para definir o padrão de movimentação. Os relacionamentos topológicos que estes padrões possuem irão definir por meio de condições espaciais/direcionais e temporais quais serão as regiões de paradas consideradas como prováveis destinos, a partir de outra região de parada, considerada como origem e, permitirão a geração de matrizes com valores de frequências relativas que consideram o número de visitas que uma região recebe a partir da outra. O que possibilita extrair valores de probabilidade condicional para cada destino provável. Portanto, a metodologia proposta e as funções desenvolvidas que foram validadas em experimentos, que utilizaram dados reais de rastreamento, fornecem uma camada inicial de inteligência aos sistemas AVL, que proporciona aos controladores destes sistemas utilizarem consultas preditivas, identificarem mais facilmente anomalias de comportamento, que possam evidenciar alguma ocorrência incomum na movimentação do veículo, além de aumentar a segurança dos veículos que possuem um dispositivo de rastreamento por meio da definição de padrões inerentes ao veículo. / The increasing development of applications used by mobile devices that make use of the technologies of satellite positioning and mobile communications, along with the popularity of these devices, whether cell phones or GPS\'s (Global Positioning System) automotive further reinforce the need for representation and understanding about the mobile entities represent in these devices and encourage studies that provide a greater meaning than the simple positional representation of these entities. It is considered in this work that these entities are tracked vehicles that provide satellite spatial position, determined by a pair of coordinates (latitude and longitude), collected at regular time intervals for systems AVL (Automatic Vehicle Location) that are responsible for monitoring the state of these vehicles. In this work, functions have been developed to predict the location and pattern generation of vehicles monitored by AVL systems. Accordingly, these stops will define common regions of the stop occurred during a period of time past and will be considered as the pattern location, while the trajectories are used to define the pattern of movement of the vehicle. The topological relationships that have these patterns define conditions through spatial/directional and temporal, which are stops regions considered as probable destinations from another stop region, regarded as origin and allow the generation of matrices with values of frequencies on considering the number of visits that region receives from the other. What makes it possible to extract values of conditional probability for each likely destination. Therefore, the proposed methodology and functions developed that been validated in experiments using real data to tracking provide a initial layer of intelligence to the AVL system that gives drivers of these systems use predictive queries, more easily identify behavioral abnormalities that may show some unusual occurrence in moving the vehicle, in addition to increasing the safety of vehicles which have a tracking device by setting patterns relating to the vehicle.
49

Metodologia de geração dinâmica de padrões de viagens rodoviárias para monitoramentos inteligentes de veículos de carga em sistemas AVL. / Dynamic generation metodology of road travel patterns to vehicles intelligent monitoring in AVL systems.

Cunha, Joana Nicolini 18 September 2008 (has links)
A presente dissertação traz a questão da aderência de viagens de veículos em monitoramentos inteligentes com sistemas Automatic Vehicle Location (AVL) que operam em rotas rodoviárias. Uma viagem é considerada como uma série de \"passadas\", que correspondem ao tempo em que o veículo está em movimento, mas excluindo os tempos gastos em paradas para atividades como carregamento/descarregamento entre outras. A partir de dados históricos coletados via Global Positioning System (GPS) pelo sistema AVL, uma metodologia de filtragem e aplicações estatísticas para geração das passadas é apresentada. Além disso, são propostos métodos para geração de padrões de viagem de referência, baseados em tempos de viagem e velocidades, desvios padrões, locais de descontinuidades entre outros parâmetros. A geração desses padrões em conjunto com procedimentos operacionais permite o monitoramento eficiente do progresso de viagens de frotas de veículos, para finalidades logísticas e de segurança. O progresso de um veículo ao longo de uma rota é analisado diante dos padrões de viagem de referência obtidos a partir de suas viagens prévias, de veículos similares na mesma rota ou de viagens em rotas de mesma classe, dependendo do que for mais adequado. A geração de padrões é um processo dinâmico que gera conhecimento sobre o veículo e comportamento da rodovia ao longo do tempo. Desenho do processo de monitoramento do progresso de viagem é apresentado, no qual, a cada nova coleta de dado GPS ou a cada instante solicitado pelo usuário, a aderência é medida, eventuais descontinuidades (saídas da rota, paradas ou mudança de sentido) são identificadas e avisos são gerados. Tal aderência é definida por índice de desempenho que considera os desvios de tempo em relação a valores de referência e respectivas tolerâncias. Para experimentação da metodologia, foi realizada simulação de viagem na rodovia BR116 na ligação São Paulo - Rio de Janeiro, sobre base com cerca de 130.000 registros de dados GPS associados. Com integração em Geographic Information System (GIS) para suporte de funcionalidades, foram gerados os padrões de viagem e simulado o processo de monitoramento com sucesso. / This dissertation addresses the question of vehicle travel adherence in intelligent monitoring with Automatic Transportation Location (AVL) operating in a regional environment. A trip is considered as series of runs, corresponding to time in movement but excluding time spent on activities such as loading/unloading and others. Based on historic data collected from AVL/GPS a statistical data filtering method to generate the runs is presented. Furthermore, statistical methods are proposed to generate travel patterns based on travel time, speed, standard deviation and other parameters. The pattern generation together with operational procedures allows effective monitoring of large fleets in logistics and safety. The progress of a vehicle along a route is evaluated face to the statistical patterns of its previous successful trips or against statistical patterns of similar vehicles on the same route, whichever appropriate. The generation of patterns is a dynamic continuous process that generates knowledge on vehicle and road behavior along time. A broad outline of the travel monitoring process is presented. Whenever the requested by user, the process calculates the travel adherence, identifies abnormalities and generates alarms. That adherence is defined by a performance index, which considers the travel time deviations from the reference values and the respective tolerances. Successful experimentation was carried out on the Rio de Janeiro - São Paulo motorway, with 130.000 Global Positioning System (GPS) positional data relayed from trucks to a Geographic Information System (GIS) based monitoring system in Brazil.
50

Mesures synchronisées par GPS pour une meilleure stabilité des réseaux

Mekki, Kérim 29 March 2002 (has links) (PDF)
La dérégulation des marchés électriques modifie en profondeur l'approche technico-économique dans l'exploitation et l'optimisation des réseaux électriques. C'est dans ce nouveau contexte que les spécialistes des réseaux électriques se voient confrontés à de nombreux défis. Ainsi, les grands réseaux électriques sont utilisés de plus en plus près de leur limite de stabilité. Cependant, faire fonctionner un réseau trop près de ses limites créer des oscillations de puissance entre les centrales de différentes régions des réseaux. Ces oscillations sont appelées oscillations <

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