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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.
1

The use of mobile mapping technology to automate surveying and monitoring of southern pine beetle

Petty, Saul David 29 August 2005 (has links)
The USDA Forest Service, Forest Health Protection, is responsible for maintaining an ORACLE database named the Southern Pine Beetle Information System (SPBIS). SPBIS was designed to store survey data for Southern Pine Beetle (SPB) infestations on federal land across the southern United States. The main purpose of this project is to improve the SPBIS database to aid in management of SPB infestations to reduce losses, to harvest compromised timber while it still has value, and to assist resource managers in preventing further infestations from becoming established. The SPBIS mobile mapping system addresses current problems with the database and offers viable solutions to each. Mobile mapping technology is a versatile tool, which is used to collect field data, with unique geospatial time tags and attributes, for integrating into or updating a GIS (Rasher 2001). The ability to efficiently collect data is essential to developing a useable database. The time required to manually enter data into the database is substantial. Ranger district personnel often do not have the time or the desire to enter data. Currently, the database is lacking years of survey and infestation data due to these negligent data entry practices, limiting the usefulness database. Currently, SPBIS data is recorded on a paper survey form. This system introduces a digital version of this form. A time study conducted to define the efficiency of each survey showed that the digital form to be more efficient with a Mann-Whitney p- value of 0.004. A comparative study was conducted to define the difference between currently estimated SPB infestation acreage and those measured using GPS. A Mann-Whitney pvalue of 0.000 shows the significant difference between the two acreage values. GPS measured acreage proved to be more accurate thus promoting the use of GPS for measuring acreage. Navigation us ing GPS coordinates was successful and will greatly decrease the time required to locate a SPB infestation on the ground. This thesis describes a mobile mapping system designed specifically to remedy the problems associated with SPBIS. This system eliminates the need for manual entry of field-collected data, while improving field data collection in terms of efficiency and accuracy.
2

Testování přesnosti mobilního mapovacího systému MOMAS / Accuracy testing of mobile mapping system MOMAS

Nováčková, Soňa January 2012 (has links)
The aim of this thesis is to introduce the mobile mapping system MOMAS, which is owned by Geodis Brno, spol. s.r.o. and test the accuracy of the system. Perform data collection and processing of data in the workplace company Geodis. In addition, identical target points, determine their coordinates and compare them with the coordinates obtained MOMAS system. And finally processed statistically derived coordinate differences.
3

3D Map Construction and Data Analysis by LiDAR for Vehicles

Tai, Chia-Hui 03 September 2012 (has links)
Nowadays, LiDAR(Light Detection And Ranging, LiDAR) is the more important and widely applicable measurement technique. The rise of visual system in 3D is very useful to the measurement of LiDAR and gets more importance value for 3D reconstruction technology, in which abundant surface features are implied in the point cloud data. Combined with the image and laser technique for real-time rendering, the LiDAR will be more functional. This thesis proposes and designs a system which combined with Laser Range Finder and 3D visual interface for vehicles, and also equipped with rotary encoder and initial measurement unit to DR(Dead Reckoning) function. Through the coordinate transform method of 2D to 3D, the 3D coordinate of each point will be calculated, and embedded with the color information which captured from the camera to take 3D color point cloud collection. This method is also called Mobile Mapping System(MMS). In addition, this mapping system uses Direct Memory Access technology to display the point cloud synchronous in 3D visual system. Except for the point cloud collection, the reconstruction of point cloud data is used in this system. The surface reconstruction is based on Nearest Neighbor Interpolation method. There are two factors to conduct the interpolation process: the angle and distance between two sample points from the points sequence. The reconstruction of point cloud and calibration of DR is not only to confirm the accuracy of 3D point cloud map but also the ¡§New Geography¡¨ of the 3D electronic map. This research will build up an independent Mobile Mapping System.
4

Caminhamento fotogramétrico utilizando o fluxo óptico filtrado

Barbosa, Ricardo Luís [UNESP] January 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2006Bitstream added on 2014-06-13T19:40:16Z : No. of bitstreams: 1 barbosa_rl_dr_prud.pdf: 1353454 bytes, checksum: 109a85af0d056d18c721a2c6af70ce93 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Em certas condições, os sensores de orientação e posicionamento (INS e GPS) de um Sistema Móvel de Mapeamento Terrestre (SMMT) ficam indisponíveis por algum intervalo de tempo casionando a perda da orientação e do posicionamento das imagens capturadas neste intervalo. Neste trabalho, é proposta uma solução baseada apenas nas imagens sem a utilização de sensores ou informações externas às mesmas, através do fluxo óptico. Um sistema móvel com um par de vídeo câmaras, denominado Unidade Móvel de Mapeamento Digital (UMMD), foi utilizado para testar a metodologia proposta em uma via plana. As câmaras são fixadas em uma base com um afastamento entre as câmaras de 0,94m e paralelas ao eixo de deslocamento (Y). A velocidade do veículo é estimada, inicialmente, com base no fluxo óptico denso. Em seguida, a estimação da velocidade é melhorada após uma filtragem, que consiste em: utilizar os vetores que apresentam comportamento radial na metade inferior das imagens e que foram detectados pelo algoritmo de Canny, acrescida uma segunda etapa na estimação da velocidade com eliminação de erros grosseiros. Com a velocidade estimada e sabendo-se o tempo de amostragem do vídeo, o deslocamento de cada imagem é determinado e esta informação é utilizada como aproximação inicial para o posicionamento das câmaras. Os resultados mostraram que a velocidade estimada ficou próxima da velocidade verdadeira e a qualidade do ajustamento se mostrou razoável, considerando-se a não utilização de sensores externos e de pontos de apoio. / Under certain conditions the positioning and orientation sensors such as INS and GPS of a land-based mobile mapping system may fail for a certain time interval. The consequence is that the images captured during this time interval may be misoriented or even may have no orientation. This thesis proposes a solution to orient the images based only on image processing and a photogrammetric technique without any external sensors in order to overcome the lack of external orientation. A land-based mobile mapping system with a pair of video cameras and a GPS receiver was used to test the proposed methodology on an urban flat road. The video cameras were mounted on the roof of the vehicle with both optical axes parallel to the main road axis (Y). The methodology is based on the velocity estimation of the vehicle, which is done in two steps. Initially, the dense optical flow is computed then the velocity estimation is obtained through a filtering strategy that consists of using radial vectors in the low parts of the images. These radial vectors are detected by the Canny algorithm. The vehicle velocity is re-estimated after eliminating the optical flow outliers. With the reestimated velocity and with the video sampling time the spatial displacement of each image (with respect to the previous one of the sequence) is determined. The results show that the estimated velocity is pretty close to the true one and the quality of the least square adjustment is quite acceptable, considering that no external sensors were used.
5

Influência da injunção da base na fototriangulação de imagens obtidas com uma unidade de mapeamento móvel

Espinhosa, Dalila Rosa Souza [UNESP] 25 August 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-25Bitstream added on 2014-06-13T20:48:54Z : No. of bitstreams: 1 espinhosa_drs_me_prud.pdf: 812310 bytes, checksum: 523e8c58d62ab6b4c0194742e34aa362 (MD5) / Em geral, um sistema móvel de mapeamento é caracterizado por um veículo automotor com um par de vídeo-câmaras montado sobre seu teto e sensores de posicionamento e navegação, tais como receptores GPS e sensores inerciais (acelerômetros, giroscópios, hodômetros etc), embarcados no interior do veículo. O processo de mapeamento topográfico e/ou cadastral com base nestes sistemas móveis consiste em capturar imagens das vias de transporte, fazer a determinação da orientação das imagens por meio da combinação de técnicas de posicionamento geodésico e técnicas fotogramétricas, armazenar as imagens georreferenciadas em um banco de imagens e daí extrair feições de interesse e representá-las cartograficamente. Os resultados mostraram que a utilização da injunção da estéreo-base tem influência em aumentar a convergência das câmaras em aproximadamente 0,1º sexagesimal e não melhorou as estimativas das coordenadas dos pontos no espaço objeto em nível de significância de 5%, nem influenciou o cálculo dos parâmetros de orientação interior. Os testes realizados com observações de qualidade pixel e subpixel indicaram que o uso de medidas subpixel é recomendado. Por meio da determinação das diferenças dos ângulos de orientação das imagens, verifica-se que os eixos ópticos não estão realmente paralelos e ortogonais à estéreo-base, há uma pequena convergência (aproximadamente 0,5º sexagesimal) e não estão no mesmo plano (desvio de aproximadamente 0,8º sexagesimal). / In general, a land-based mobile mapping system is featured by a vehicle with a pair of video cameras mounted on its roof and positioning and navigation sensors such as GPS receivers and inertial sensors (accelerometers, gyros, odometers etc) loaded in the vehicle. The topographic and/or cadastral mapping process based on these mobile systems consists on capturing road images, determining the image orientation by geodetic and photogrammetric techniques, saving the georeferenced images in an image database and then extracting and mapping interest features. The results show that the stereo base constraint has influence on to increase camera convergence on 0.1 sexagesimal degree and improves but not significantly, in 5% level, the object point X coordinate estimation, and has minor influence on the interior orientation parameters. The experiments with pixel and subpixel observation indicated that subpixel quality is recommended. Finally, considering the differences of the image orientation angles, it is verified that the optical axes are not truly parallel and orthogonal to the stereo base. In other words, there is a little convergence (0.5 sexagesimal degree) between the optical axes and they are not in the same plain (0.8 sexagesimal degree deviation).
6

Influência da injunção da base na fototriangulação de imagens obtidas com uma unidade de mapeamento móvel /

Espinhosa, Dalila Rosa Souza. January 2006 (has links)
Orientador: João Fernando Custódio da Silva / Banca: Jorge Luís Nunes e Silva Brito / Banca: Aluir Porfírio Dal Poz / Resumo: Em geral, um sistema móvel de mapeamento é caracterizado por um veículo automotor com um par de vídeo-câmaras montado sobre seu teto e sensores de posicionamento e navegação, tais como receptores GPS e sensores inerciais (acelerômetros, giroscópios, hodômetros etc), embarcados no interior do veículo. O processo de mapeamento topográfico e/ou cadastral com base nestes sistemas móveis consiste em capturar imagens das vias de transporte, fazer a determinação da orientação das imagens por meio da combinação de técnicas de posicionamento geodésico e técnicas fotogramétricas, armazenar as imagens georreferenciadas em um banco de imagens e daí extrair feições de interesse e representá-las cartograficamente. Os resultados mostraram que a utilização da injunção da estéreo-base tem influência em aumentar a convergência das câmaras em aproximadamente 0,1º sexagesimal e não melhorou as estimativas das coordenadas dos pontos no espaço objeto em nível de significância de 5%, nem influenciou o cálculo dos parâmetros de orientação interior. Os testes realizados com observações de qualidade pixel e subpixel indicaram que o uso de medidas subpixel é recomendado. Por meio da determinação das diferenças dos ângulos de orientação das imagens, verifica-se que os eixos ópticos não estão realmente paralelos e ortogonais à estéreo-base, há uma pequena convergência (aproximadamente 0,5º sexagesimal) e não estão no mesmo plano (desvio de aproximadamente 0,8º sexagesimal). / Abstract: In general, a land-based mobile mapping system is featured by a vehicle with a pair of video cameras mounted on its roof and positioning and navigation sensors such as GPS receivers and inertial sensors (accelerometers, gyros, odometers etc) loaded in the vehicle. The topographic and/or cadastral mapping process based on these mobile systems consists on capturing road images, determining the image orientation by geodetic and photogrammetric techniques, saving the georeferenced images in an image database and then extracting and mapping interest features. The results show that the stereo base constraint has influence on to increase camera convergence on 0.1 sexagesimal degree and improves but not significantly, in 5% level, the object point X coordinate estimation, and has minor influence on the interior orientation parameters. The experiments with pixel and subpixel observation indicated that subpixel quality is recommended. Finally, considering the differences of the image orientation angles, it is verified that the optical axes are not truly parallel and orthogonal to the stereo base. In other words, there is a little convergence (0.5 sexagesimal degree) between the optical axes and they are not in the same plain (0.8 sexagesimal degree deviation). / Mestre
7

A rigorous approach to comprehesive performance analysis of state-of-the-art airborne mobile mapping systems

May, Nora Csanyi 08 January 2008 (has links)
No description available.
8

Mobilní mapování v architektuře / Using of Mobile Mapping in Architecture

Deutsch, Jiří January 2013 (has links)
This diploma thesis describes the application and using of mobile mapping in architecture. After getting to know the mobile mapping system MOMAS, which was developed by Geodis Brno, spol. s.r.o., in this way some localities in Brno were measured. From that measuring was chosen the facade of Dům Milady Horákové, and by post-processing was the facade compiled and created into 3D model. In addition the control measuring was done by non-prism method, following the assessment of accuracy.
9

Detekce prostorových objektů v mračně bodů / Detection of spatial objects in a point cloud

Venený, Petr Unknown Date (has links)
The diploma thesis deals with processing of a point cloud that was collected via mobile mapping system. The first part sets a theoretical background, starting with mapping in general moving to mobile mapping systems and their particular parts. The practical part describes the whole process of data collecting, testing the automatic detection of spatial objects based on a point cloud and its visualisation. The results of the diploma thesis are GIS data layers and an evaluation of the process.
10

Estimation de pose de grands blocs d'images panoramiques issues de systèmes de numérisation mobile / Pose estimation on large block of panoramic images from mobile mapping systems

Cannelle, Bertrand 04 December 2013 (has links)
Tirée par le développement et la démocratisation des globes numériques et des systèmes de géolocalisation grand public, la numérisation 3D mobile terrestre en milieux urbains s'est développée de manière très importante ces dix dernières années. Les principaux verrous résiduels de ces systèmes reste d'une part la localisation précise des données pour certaines applications (conduite autonome urbaine, levers de géomètres, etc.) du fait des masques et multi-trajets GPS dans les canyons urbains et d'autre part le passage à l'échelle du traitement de l'information vu les volumes de données considérables acquis chaque jour (plusieurs To).La première partie de cette thèse est consacrée à la présentation de la numérisation mobile, aussi bien du point de vue système que du point de vue usage. Une description fine du système Stéréopolis V2, véhicule de numérisation mobile multi-caméras développée au laboratoire MATIS de l'Institut National de l'Information Géographique et Forestière, est faite afin de présenter les données utilisées dans cette thèse. Les blocs d'images manipulés dans ces travaux sont constitués de plusieurs centaines de milliers à un million d'image. La seconde partie est consacrée à la calibration du système: calibration intrinsèque de caméra, tout d'abord, en utilisant une géométrie d'acquisition de type panoramique, qui permet de s'affranchir de réseaux de cibles 3D métrologiques. Une calibration extrinsèque des imageurs du véhicule, ensuite, qui permet de déterminer de façon précise la position et l'orientation de caméras sur un dispositif de numérisation mobile. Deux procédures sont détaillées et comparées: l'une dite "off-line" nécessitant une acquisition spécifique avec un réseau de cibles métrologiques et l'autre dite "on-line" utilisant uniquement les données d'acquisition standards. Nous démontrons que la méthode "on-line" produit dans les mêmes conditions une précision comparable à celle "off-line" tout en étant plus adaptée aux variations de conditions d'acquisition in-situ. La troisième partie détaille le processus de compensation par faisceaux appliquée aux données de numérisation mobile multi-caméras qui permet d'estimer la pose d'un grand nombre d'images. La mise en équation ainsi que différents cas d'utilisations de la méthode sont explicités. La structuration et la gestion des données dans un entrepôt est elle aussi développée car elle permet la gestion d'importants volumes et donc le passage à l'échelle tout en restant performante. La quatrième et dernière partie propose différentes méthodes de recalage qui peuvent être utilisées aussi bien de manière individuelle que combinées afin de permettre de mettre en cohérence des séquences d'images distinctes (boucles, passage multi-dates, etc.) dans des contextes applicatifs différents / Mobile mapping technology has grown exponentially the last ten years, particularly due to advances in computer and sensor performances. However, the very accurate positioning of data generated by such technique remains a crucial issue. The first part of this thesis presents the mobile mapping system that has been designed in the MATIS lab of IGN as well as its operational use. A detailed analysis of image data is proposed and data used for this work is discussed. The second part tackles the standard calibration procedure. First, camera calibration is performed by using a panoramic-based acquisition geometry, which allows not to required ground control points. Secondly, a full calibration procedure dedicated to the Stéréopolis V2is proposed so as to determine accurately the position and orientation of all the cameras. For that purpose, two procedures are explained : one requiring an area with points positioned with high accuracy ,and the other one based only the data acquisition. The third section details the compensation applied to the mobile mapping car that allows to improve poses of a large number of images. The mathematical formulation is proposed, and various cases of the method are explained. Data management is also presented since it is a mandatory step for efficient large amount of data management The fourth and final part of the thesis presents different registration scenarii, where methods developed in this work can be used individually as well as combined with other ones so as to bring higher coherence between sequences of distinct images

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