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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.
101

Development and research of the test bench for the angle calibration of geodetic instruments / Geodezinių kampų matavimo prietaisų kalibravimo įrangos kūrimas ir tyrimas

Bručas, Domantas 20 June 2008 (has links)
The main idea of current PhD thesis is an accuracy analysis of testing and calibration of geodetic instruments. The object of investigation is an analysis of means and methods for testing and calibration of geodetic instruments for plane angle measurement, development of such calibration equipment, its accuracy investigation and the research of its accuracy increasing possibilities. These objects are important for successful testing or calibration of geodetic instruments for angle measuring which is essential in ensuring the precision of measurements taken in surveying, construction, mechanical engineering, etc. There are several main goals of the presented work. First one is an analysis of the angle measuring methods and devices suitable for the testing and calibration of geodetic instruments, according to the results of the mentioned analysis the second task can be formulated – creation of a multi-reference plane angle testing and calibration equipment at Institute of Geodesy, Vilnius Gediminas Technical University and investigate the parameters of its accuracy. The third task is to investigate the accuracy increasing possibilities of the equipment, and implementation some of them into the practice. The thesis consists of four chapters, introduction, conclusions, list of references and appendixes. Introduction is dedicated for an introduction to the problem and its topicality. There are also formulated purposes and tasks of the work; the used methods and novelty of... [to full text] / Disertacijoje nagrinėjamos geodezinių kampus matuojančių prietaisų patikros bei kalibravimo metodai bei priemonės. Pagrindinis tyrimo objektas yra geodezinių prietaisų tikslumo parametrų matavimo būdų ir priemonių analizė, kalibravimo įrenginio kūrimas, jo tikslumo charakteristikų tyrimas bei įrenginio tobulinimas. Šie objektai yra svarbūs vykdant geodezinių prietaisų kalibravimą, kas savo ruožtu yra labai svarbu užtikrinant reikiamą šių prietaisų matavimų tikslumą geodezijoje, statybose, mašinų gamyboje ir t. t. Pagrindinis disertacijos tikslas – geodezinių kampų matavimo prietaisų kalibravimo galimybių analizė ir sukurto kalibravimo įrenginio tikslumo para¬metrų tyrimas. Darbe sprendžiami keli pagrindiniai uždaviniai: plokščiųjų kampų mata¬vimo metodų bei įrenginių, tinkamų geodeziniams prietaisams kalibruoti, analizė; daugiaetalonio kampų kalibravimo stendo kūrimas Vilniaus Gedimino technikos universiteto Geodezijos institute bei jo tikslumo charakteristikų tyri¬mas; stendo tikslumo didinimo galimybių bei priemonių tyrimas, ir apskri¬timinių skalių kalibravimo būdų tobulinimas. Disertaciją sudaro šeši skyriai, įvadas, išvados, literatūros sąrašas bei priedai. Įvade nagrinėjamas problemos aktualumas, formuluojamas darbo tikslas bei uždaviniai, aprašomas mokslinis darbo naujumas, pristatomi autoriaus pranešimai ir publikacijos, disertacijos struktūra. Pirmasis skyrius skirtas labiausiai paplitusių plokščiųjų kampų matavimo būdų bei priemonių tinkamų geodeziniams prietaisams... [toliau žr. visą tekstą]
102

Geodezinių kampų matavimo prietaisų kalibravimo įrangos kūrimas ir tyrimas / Development and research of the test bench for the angle calibration of geodetic instruments

Bručas, Domantas 20 June 2008 (has links)
Disertacijoje nagrinėjamos geodezinių kampus matuojančių prietaisų patikros bei kalibravimo metodai bei priemonės. Pagrindinis tyrimo objektas yra geodezinių prietaisų tikslumo parametrų matavimo būdų ir priemonių analizė, kalibravimo įrenginio kūrimas, jo tikslumo charakteristikų tyrimas bei įrenginio tobulinimas. Šie objektai yra svarbūs vykdant geodezinių prietaisų kalibravimą, kas savo ruožtu yra labai svarbu užtikrinant reikiamą šių prietaisų matavimų tikslumą geodezijoje, statybose, mašinų gamyboje ir t. t. Pagrindinis disertacijos tikslas – geodezinių kampų matavimo prietaisų kalibravimo galimybių analizė ir sukurto kalibravimo įrenginio tikslumo parametr�� tyrimas. Darbe sprendžiami keli pagrindiniai uždaviniai: plokščiųjų kampų matavimo metodų bei įrenginių, tinkamų geodeziniams prietaisams kalibruoti, analizė; daugiaetalonio kampų kalibravimo stendo kūrimas Vilniaus Gedimino technikos universiteto Geodezijos institute bei jo tikslumo charakteristikų tyrimas; stendo tikslumo didinimo galimybių bei priemonių tyrimas, ir apskritiminių skalių kalibravimo būdų tobulinimas. Disertaciją sudaro šeši skyriai, įvadas, išvados, literatūros sąrašas bei priedai. Įvade nagrinėjamas problemos aktualumas, formuluojamas darbo tikslas bei uždaviniai, aprašomas mokslinis darbo naujumas, pristatomi autoriaus pranešimai ir publikacijos, disertacijos struktūra. Pirmasis skyrius skirtas labiausiai paplitusių plokščiųjų kampų matavimo būdų bei priemonių tinkamų geodeziniams prietaisams... [toliau žr. visą tekstą] / The main idea of current PhD thesis is an accuracy analysis of testing and calibration of geodetic instruments. The object of investigation is an analysis of means and methods for testing and calibration of geodetic instruments for plane angle measurement, development of such calibration equipment, its accuracy investigation and the research of its accuracy increasing possibilities. These objects are important for successful testing or calibration of geodetic instruments for angle measuring which is essential in ensuring the precision of measurements taken in surveying, construction, mechanical engineering, etc. There are several main goals of the presented work. First one is an analysis of the angle measuring methods and devices suitable for the testing and calibration of geodetic instruments, according to the results of the mentioned analysis the second task can be formulated – creation of a multi-reference plane angle testing and calibration equipment at Institute of Geodesy, Vilnius Gediminas Technical University and investigate the parameters of its accuracy. The third task is to investigate the accuracy increasing possibilities of the equipment, and implementation some of them into the practice. The thesis consists of four chapters, introduction, conclusions, list of references and appendixes. Introduction is dedicated for an introduction to the problem and its topicality. There are also formulated purposes and tasks of the work; the used methods and novelty of... [to full text]
103

Transformation av geodetiska höjdnät med flygburen laserskanning : En inledande genomförbarhetsstudie

Dalheimer, Jan January 2018 (has links)
När kraven på mätosäkerhet är hög vid geodetiska mätningar behövs geodetiska referenssystem realiserade av geodetiska nät av hög kvalitet. Etableringen och transformation till överordnade referenssystem i höjd av dessa nät genomförs idag ofta med terrestra metoder som avvägning, vilket är ett noggrant men tidskrävande arbete. Det finns flera försök att använda sig av andra metoder såsom GNSS, men en möjlighet skulle även vara att använda punktmoln från flygburen laserskanning. Detta arbetes syfte är att undersöka om punktmoln kan användas till transformation av ett geodetiskt höjdnät i Sandvikens kommun. Nätet består av cirka 500 fixpunkter och har 2010 transformerats till RH2000 av Lantmäteriet. Det använda punktmolnet har producerats av Lantmäteriet och har en medelavvikelse om 0,05 m på plana hårdgjorda ytor. Detta är relativt högt då vanligen osäkerheter på millimeternivå önskas vid transformationer. Men eftersom medeltal kan reducera slumpmässiga avvikelser i enskilda mätningar kan en transformation bestående av ett medelhöjdskift möjligen ge ett tillfredsställande resultat. Medelhöjdskiftet är då ett medeltal av flera höjdskift beräknade på olika ställen i punktmolnet. Genom att avväga höjdskillnaden mellan fixpunkterna i nätet och punkter på markytan som med olika metoder höjdbestäms utifrån punktmolnet har höjder för fixpunkterna enligt punktmolnet erhållits. Dessa har jämförts med RH2000 höjder enligt Lantmäteriets transformation för att beräkna en avvikelse, samt med de äldre lokala höjderna för att beräkna ett höjdskift. Genom att beräkna medelvärde och dess osäkerhet för höjdskiftet över hela nätet har en uppfattning om metodens lämplighet erhållits. Höjdskiften låg överlag inom några millimeter från det som Lantmäteriet beräknat, med 3 mm osäkerhet för den överlag bästa metoden. Även om höjdskiftets och därmed transformationens osäkerhet delvis blev något hög jämfört med avvägning så kan punktmoln ändå vara ett lämpligt alternativ. Speciellt i mera avlägsna områden utan bra anknytningar till det överordnade nätet kan det vara intressant. Det finns dock många parametrar som ännu inte utforskats, bland annat vissa eventuella systematiska avvikelser. / When the requirements on accuracy and precision are high for geodetic measurements you need geodetic reference systems realized with geodetic control networks of high quality. Today, establishment and transformation to higher order reference systems for height usually uses terrestrial methods like levelling. While highly accurate these result in time consuming work. There have been a couple attempts at using other methods for this task, for example GNSS, but another possibility might be usage of point clouds from airborne laser scanning. As a starting point for further studies this study attempts to use point clouds to transform a geodetic height network in Sandviken municipality, Sweden. The network consists of around 500 benchmarks and has been transformed to the national reference system for height, RH2000, by the Swedish national geodetic survey (Lantmäteriet) in 2010. The point cloud used is also produced by Lantmäteriet and is said to have a mean error of 0,05 m. This is relatively high since the requirements usually are in the millimeter range when determining transformation parameters, but if the transformation only consist of a single height shift calculated as a mean from several height shifts derived from the point cloud any random errors in the point cloud should be reduced. By measuring the height difference between benchmarks and points on the ground, that through different methods are given heights according to the point cloud, heights of the benchmarks have been determined according according to the point cloud. These can be compared to heights in RH2000 according to the transformation performed by Lantmäteriet to see their deviation from the assumed true value. Further comparisons against the older local heights of the benchmarks give a height shift that can be used as a simple transformation. By calculating a mean and uncertainty an estimation of the suitability of the method can be achieved. The all height shifts deviated a few millimeters from the result Lantmäteriet got, with uncertainties around 3 mm for the overall best method. Even if the uncertainty of the shift and therefore the transformation ended up somewhat high compared to what Lantmäteriet achieved it is still believed that point clouds may be or become a viable alternative. Especially in more remote regions without good connections to the higher order network. There are many parameters that have not yet been explored though, as well as some potential systematic errors that should be further investigated.
104

A modelagem tridimensional no tratamento do problema direto da geodésia / The tridimensional modeling in processing of direct geodetic problem

Pimentel, Daniel Carlos Cheron 29 March 2012 (has links)
For the transformation of the local coordinates in the global coordinates, and contrariwise, it can be employed the traditional method of Puissant or the 3D modelling. In this paper, both approaches were applied in the geodetic transport of the coordinates of a topographic polygonal, framed in the geodetic base lines AB and CD, considering the point B as the origin of the systems. The geodetic coordinates of supporting points (A, B, C and D) which were determined with GPS (Glogal Positioning System) and the observations which were obtained in topographic search. From the local coordinates (v, u, w) the polygon was calculated: the topographic components (Δv, Δu, Δw) and 3D modeling was transformed in geodesic components (ΔX, ΔY, ΔZ); the geodetic cartesian coordenates (X, Y, Z) which were subsequently transformed in geodetic coordenates (φ, λ, h). In the solution of the Geodetic Direct Problem (PGD) were used the topographic observations, corrected end reduced to the ellipsoid. The results comparison obtained by applying the two methodologies, suggested here, shows a standard deviation (σ) of ± 7,31x10-4 for the latitude (φ) and a standard deviation (σ) of ± 3,71x10-4 for the longitude (λ). This result in an uncertainty of ± 0,080 meters, in 95% significance level between the average position of a point determined by the 3D modeling and PGD. The change in the origin of the system did not cause a relative error above the limit established by the NBR 13.133 (Brasilian Norm 13.133), at the distances between the extreme points of the polygon. These results allow, in this case, the replacement of the PGD methodology for the 3D modeling and choose any point in the spatial database for origin of the systems. The 3D function model performs the conversion of the topographic coordindates in geodetic coordinates with equivalent accuracy to the traditional method of Puissant, with fewer calculations and enables reverse process. This methodology can be used for georeferencing and mapping work, rural and urban cadastre, cartographic updating, among others, in which uncertainty found can be accepted. The data suggest more evaluations of the functional model and the introduction of the stochastic model, for evaluating the quality of data and system. Keywords: Geodesy. Topography. Direct Geodetic Problem. 3D Modelling / Para a transformação de coordenadas locais em globais, e vice-versa, podese empregar a solução do Problema Geodésico Direto (PGD) por Puissant ou a metodologia da modelagem 3D. Neste trabalho, ambas as metodologias foram aplicadas no transporte geodésico das coordenadas de uma poligonal topográfica, enquadrada nas linhas de base geodésica AB e CD, considerando o ponto B como origem dos sistemas. As coordenadas geodésicas dos pontos de apoio (A, B, C e D) foram determinadas no levantamento com GPS (Global Positioning System) e as observações topográficas foram obtidas no levantamento topográfico. A partir das coordenadas locais (v, u, w) da poligonal foram: calculadas as componentes topográficas (Δv, Δu, Δw) e transformadas em componentes geodésicas (ΔX, ΔY, ΔZ) por meio da modelagem 3D; calculadas as coordenadas geodésicas cartesianas (X, Y, Z) que posteriormente foram transformadas em coordenadas geodésicas (φ, λ, h). Na solução do PGD, utilizaram-se as observações topográficas corrigidas e reduzidas ao elipsóide. A comparação dos resultados obtidos pela aplicação das duas metodologias, aqui propostas, apresenta um desvio-padrão (σ) de ± 7,31x10-4 segundos para a latitude (φ) e um desvio-padrão (σ) de ± 3,71x10-4 segundos para a longitude (λ). O que resulta em uma incerteza de ± 0,080 m, ao nível de significância de 95 %, entre a posição média de um ponto determinada pela modelagem 3D e pelo PGD. A alteração da origem do sistema não acarretou um erro relativo superior ao limite estabelecido pela NBR 13.133, nas distâncias entre os pontos extremos da poligonal. Estes resultados possibilitam, neste caso, a substituição da metodologia do PGD pela modelagem 3D e a escolha qualquer ponto da base de dados espaciais como origem do sistema. O modelo funcional 3D realiza a conversão das coordenadas topográficas em geodésicas com precisão equivalente ao método tradicional de Puissant, com quantidade menor de cálculos e possibilita a realização do processo inverso. Esta metodologia pode ser utilizada para trabalhos de georreferenciamento e mapeamento, cadastro urbano e rural e atualização cartográfica, entre outros, em que se possa admitir a incerteza encontrada. Os dados sugerem mais avaliações do modelo funcional e a introdução do modelo estocástico para avaliações da qualidade dos dados e do sistema.
105

Návrh a vybudování sítě bodů podrobného polohového bodového pole metodou geodetickou a GPS. / Project and realisation of the network for planimetry control points using the methods geodetic and GPS.

VÁLKA, Michal January 2009 (has links)
This thesis was elaborated on the topic: Project and realisation of the network for planimetry control points using the methods geodetic and GPS. The aim was carry out the reconnaissance of the terrain, valorize of the current state of the point field in the selected locality, as necessary complete him in the density for the detailed mapping of big ratio scale and locate. All calculations, evaluation of the accuracy and processing of the graphic supplements were a part of this thesis. The point network was built in the cadastral territory Horní Planá in the drainage area of the river Ostřice. Following the geodetic data and the map basis was effected the reconnaissance of the selected locality, the stabilization of the new points PPBP and after that they were positional located. On the whole there were stabilized 14 new points. They were located by using the total station Leica TC407 by the help of double - sided incorporated and double - sided oriented polygonal traverse and by using GPS station Trimble 4600LS for the fast static method.
106

Realizace a zaměření sítě polohových a výškových bodů v povodí Ostřice různými metodami. / Project and surveying of the network for planimetry and hight points in the area of the river Ostřice using several methods.

FINK, Miroslav January 2009 (has links)
In this thesis was elaborated the topic: Project and surveying of the network for planimetry and hight points in the area of the river Ostřice using several methods. It{\crq}s purpose was a reconnaissance of the part of a basin of Ostřice, assessment of existing point field, propose and complete the point network for planimetry in sufficient density for further surveying work in the area and survey of location and level by using geodetic methods and GPS. The reconnaissance of the area was conducted due to geodetic and levelling data of the points and maps. A network of 18 points of the detailed point network was built. I located nine of them by using a GPS method and a method of polygonal traverse. The electronic total station Leica TC 407 was used for the point survey by the method of polygonal traverse, for the GPS method was used a GPS apparatus Trimble 4600LS. Altitude of the points was determined by the method of technical levelling. For the altitude determination was used a Topcon AT {--} 24A levelling device.
107

Monitoração, por GPS, de deslocamentos em estruturas com carga dinâmica. / Monitoring, by GPS, of displacements in structures with dynamic loads

Régis Fernandes Bueno 20 June 2007 (has links)
A monitoração dinâmica de pontes rodoviárias através da determinação de deslocamentos espaciais é uma das atuais áreas de interesse da geodésia. A tecnologia de posicionamento por satélite é uma das ferramentas disponíveis para este fim e foi avaliada nesta pesquisa. Verifica-se que o GNSS pode contribuir para com o monitoramento dinâmico de estruturas e nos últimos anos se observam aplicações em grandes pontes estaiadas na Ásia, na Europa e na América do Norte. No presente estudo analisou-se a aplicação desta tecnologia em uma estrutura mais rígida, sob vinculo com uma rede de referência única e sob as condições apresentadas pela região brasileira. Foram realizados ensaios em um shaker, na Base de Calibração de Instrumentos Geodésicos da USP e na estrutura do Viaduto Ascendente 19 da rodovia dos Imigrantes, empregando-se a tecnologia GPS e análise modal. A partir de determinações no método relativo cinemático obtiveram-se os deslocamentos tridimensionais e a freqüências do primeiro modo de vibração da estrutura. A metodologia aplicada e os resultados obtidos demonstram a potencialidade do método também para estruturas mais rígidas e sob condições características da região brasileira, que diferem de outras partes do globo no que tange a tecnologia GPS. Ao final é sugerida uma Proposta Básica de Metodologia para a Monitoração de Estrutura com Carga Dinâmica pela Utilização de GNSS. / The dynamic monitoring of road bridges though spatial displacements is one of the geodetic areas of interests. The satellite positioning technologies are one of the disposed tools for this task and were evaluate by present research. One verifies that GNSS can contribute for the dynamic monitoring of structures, and has applied for this task in the last years to large cable stayed bridges on Asia, on Europe and on North America. On the present study, one analyses the use of this technology in a more rigid structure, tied to a unique reference network and under Brazilian region conditions. Were realized essays over a shaker on USP Geodetic Instrumental Calibration Base and over the Imigrantes Roadway Ascending Viaduct 19 employing the GPS technology and modal analysis. By determinations in the kinematics relative method ones obtain the tridimensional displacements and the frequency of first modal shape of the structure. The applied methodology and its obtained results demonstrate the potentiality of this method for more rigid structure too, and under Brazilian region characteristics. At the end is proponed a Methodological Basic Proposal for Dynamic Charged Structure Monitoring thru GNSS Employment.
108

Implantação, calculo e ajustamento de redes geodesicas visando a elaboração de carta geoidal para a cidade de Campinas / Implantation, calculation and adjustment of geodetic network seeking geoid map elaboration for Campinas city

Innocente, Erico Francisco 31 August 2007 (has links)
Orientador: Jorge Luiz Alves Trabanco / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T18:04:32Z (GMT). No. of bitstreams: 1 Innocente_EricoFrancisco_M.pdf: 11372115 bytes, checksum: b9b472d335b6c8e71df724c39ded054a (MD5) Previous issue date: 2007 / Resumo: A procura por soluções de problemas referentes à aquisição de dados cadastrais, dentro da malha urbana de uma cidade, com posicionamento GPS relativo, tem se intensificado nos últimos anos. Quando uma nova tecnologia é introduzida em determinada atividade de uma organização, seja ela pública ou privada, percebe-se que sua utilização fica aquém das reais possibilidades de aproveitamento das funções disponibilizadas pelo fabricante. Essa subutilização da tecnologia/equipamento é, na maioria dos casos, devido à falta de infra-estrutura básica existente no local de atuação e a falta de preparo dos usuários. Está constatado que as determinações altimétricas, utilizando tecnologia GPS, não tem todas as suas funções exploradas devido, primordialmente, a falta de uma carta geoidal que possibilite a correção da ondulação geoidal, diferença entre as altitudes geométricas e as correspondentes ortométricas, sendo esta última a altitude utilizada em obras de engenharia. A comunidade científica, empresas de engenharia e órgãos públicos sabem da necessidade desta carta geoidal, onde é possível contribuir com a melhoria da acurácia das altitudes e aplicação direta nos levantamentos planialtimétricos cadastrais dentro do perímetro urbano da cidade. Portanto a motivação deste trabalho é obter um modelo geoidal para a Cidade de Campinas, melhorando a acurácia da ondulação do geóide e proporcionando o emprego do GPS na determinação de altitude ortométrica que, é fator primordial aos projetos e obras inerentes ao dia a dia da Administração Pública, do saneamento básico e das empresas de engenharia / Abstract: The search for solutions of problems concerning the acquisition of cadastral data, in the urban mesh of a city, with GPS relative positioning, has intensified in the last years. When a new technology is introduced in certain activity of an organization, public or private, one notice its utilization is below the real possibilities of use of the functions available by the manufacturer. This sub technology/equipment use is, in most of the cases, due to the lack of basic infrastructure existing in the actuating place and the lack of the users preparation. It has been verified that the altimetric determinations, using GPS technology, don't have all the possible functions explored due to the lack of a geoid map that makes the geoidal height correction possible, difference between the geometric height and the correspondent orthometrics, being this last one the altitude used in engineering works. The scientific community, engineering companies and public organs know the need of this geoid map, where it is possible to contribute with the accuracy improvement of the height and direct application in the cadastral surveying inside the urban perimeter. Therefore the motivation of this work is to obtain a geoid model for Campinas City, improving the accuracy of the geoidal height and providing the GPS use in the determination of orthometric height that is fundamental factor for the projects and inherent to the daily works to the of the Public Administration, basic sanitation and engineering companies / Mestrado / Transportes / Mestre em Engenharia Civil
109

3D model hvězdárny ve Valašském Meziříčí / 3D model of observatory building in Valašské Meziříčí

Dubec, Marek January 2018 (has links)
The objective of the diploma thesis is creating digital 3D model of observatory building in Valašské Meziříčí. The building is measured by classical geodetic methods. The results of the thesis are the wired model, which is created in MicroStation V8i, and 3D model with textured surfaces, including visualization in form photos and video, which is created in AutoCAD 2018.
110

3D model vybraného objektu / 3D model of selected object

Barancová, Simona January 2017 (has links)
The aim of this thesis is creation of 3D model by a selected program. In the introduction of the thesis is a brief description of chosen object – St. Václav's temple in Brno. Next follows preparation works before measuring, creating of measuring net by GNSS and measuring of object by tachymetric method. In the following chapters is briefly described 2D and 3D computer graphic and program AutoCAD Civil 3D, which was used for create resulting model of the object.

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