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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

Opakovaná nivelace na vodním zdroji Tetčice / Precise repeated leveling measurements at Tetčice water reservoir

Čáp, Pavel January 2012 (has links)
This master’s thesis deals with the vertical movements of foundation soil in village Tetčice. In the first part describes geological structures and problems in locality. A next chapter deals with surveying vertical movements, measurements and evaluation. As addition is measurement actually groundwater level depending on the line levelling.
42

Etablering av ett nytt höjdnät i RH 2000 vid Högskolan i Gävle

Faisal Ali, Ali, Wennberg, David January 2021 (has links)
RH 2000 är Sveriges nationella höjdsystem och det bygger på den tredje precisionsvägningen som genomfördes i Sverige mellan 1979 och 2003. Nätet för RH 2000 har en starkare geometri och är mer homogent än vid de tidigare två precisionsavvägningarna och höjdnäten (RH 00, RH 70). Under de senaste 14 åren har mycket arbete lagts ned på att få kommuner, myndigheter och andra samhällsaktörer att byta till RH 2000, detta för att få enhetlighet och främja datautbyte. Nu har de flesta aktörer anslutit sig till det nya nätet, men det finns fortfarande de som använder de äldre referenssystemen från den de två tidigare precisionsavvägningarna.  Högskolan i Gävle har länge använt sig av ett höjdnät som anslutits till RH 70. Man har visserligen gjort en preliminär anslutning till RH 2000, men denna har gjorts genom mätning med Global Navigation Satellite System (GNSS) och den nationella geoidmodellen. Höjdnätet skall ligga till grund för högskolan inom utbildning och forskning inom lantmäteriteknik, det är därför ett bra höjdnät behövs vid HiG. Nätet bör vara av hög kvalité, och det är därför viktigt att etablera nätet genom avvägning. Höjdbestämning med GNSS har högre osäkerhet jämfört med den traditionella metoden för etablering av höjdnät (avvägning). Ett syfte med denna studie är att etablera ett nytt stomnät i höjd som är hållbart över tid vid Högskolan i Gävles campus och genom finavvägning ansluta detta till riksnätet för det nationella höjdsystemet RH 2000 på ett så bra och tillförlitligt sätt som möjligt. Ett annat syfte är också att undersöka och jämföra skillnad i höjd mellan de nya och äldre höjdnätsrealiseringarna vid skolan, samt även att undersöka hur de nya avvägda RH 2000-höjderna stämmer med geoidmodellen lokalt med hjälp av höjder bestämda från GNSS- mätning och SWEPOS tjänst för Nätverks Real Time Kinematic (NRTK).  I detta examensarbete har finavvägning genomförts med det digitala avvägningsinstrument Leica DNA03 för att etablera ett anslutningsnät för samhällsbyggnad (klass A2 enligt Handbok i mät- och kartfrågor,HMK). Utvärdering av mätosäkerhet har gjorts i enlighet med de styrdokument som examensarbetet följer, nämligen HMK och SIS-TS 21143:2016. Stegvis utförda utjämningar av nätet resulterade i bra skattade höjder med standardosäkerheter på millimeternivå i RH 2000. Genom det nya höjdnätet anslutet till RH 2000 har Högskolan i Gävle erhållit ett nytt höjdnät med låga osäkerheter som möter kraven för anslutningsnät och framtida övningar på högskolan kommer att göras i en högkvalitativ realisering av RH 2000. / RH 2000 is the national height system/frame of Sweden. It is based on the third precision precise levelling that was carried out in Sweden between 1979 and 2003. The network for RH 2000 has a stronger geometry and is more homogeneous than for the previous two Swedish precise levellings and the height networks (RH00, RH70). During the last 14 years, a lot of work has been put into getting municipalities, state authorities and other community operators to switch to RH 2000, in order to achieve uniformity and promote data exchange. Most have now joined the new network, but some still use the older reference systems of the two previous precise levellings.  The University of Gävle has for a long time used a height network that has been connected to RH 70. Although a preliminary connection has been made to RH 2000, it has been made through Global Navigation Satellite System (GNSS) measurements and with the national geoid model. The height network shall form the basis for the university in education and research in surveying, which is why a good height network is needed at HiG. The network should have a high quality; therefore, it is important to establish the network by levelling. The determination of height with GNSS has higher uncertainty compared with the traditional method for establishing a height network (levelling). A purpose of this study is to establish a new geodetic control network in height that is sustainable over time at the Campus of the University of Gävle and through to connect it to the national height network/system RH 2000 in the best and most reliable way. Another purpose is also to investigate and compare differences in height between the new and older height networks, and it is also investigated whether the levelled RH 2000 heights match with the national geoid model locally by using heights determined from GNSS measurements and SWEPOS service for Network Real Time Kinematic (NRTK).  In this thesis, digital levelling has been carried out with the digital level instrument Leica DNA03 to establish a control network for urban management (class A2 according to Handbook of measurement and map issues,HMK). Evaluation of measurement uncertainty has been made in accordance with the governing documents that the thesis follows, namely Swedish HMK and SIS-TS 21143: 2016. Step-by-step adjustments of the network resulted in well estimated heights with standard uncertainties at the millimeter level in RH 2000. Through the heights in RH 2000 for the new network, the University of Gävle has received a new height network with low uncertainties that meets the requirements for connection networks and future exercises at the university can be made in a high-quality realization of RH 2000.
43

Precise Gravimetric Geoid Model for Iran Based on GRACE and SRTM Data and the Least-Squares Modification of Stokes’ Formula : with Some Geodynamic Interpretations

Kiamehr, Ramin January 2006 (has links)
Iran is one of the most complicated areas in the world from the view of rough topography, tectonic activity, large lateral density and geoidal height variations. The computation of a regional gravimetric geoid model with high accuracy in mountainous regions, especially with sparse data, is a difficult task that needs a special attention to obtain reliable results which can meet the needs of the today geodetic community. In this research different heterogeneous data has been used, which includes gravity anomalies, the high-resolution SRTM Digital Elevation Model (DEM), recently published GRACE Global Geopotential Models (GGMs), geological maps and GPS/levelling data. The above data has been optimally combined through the least-squares modification of Stokes formula with additive corrections. Regarding the data evaluation and refinement, the cross-validation technique has been used for detection of outliers. Also, several GGMs and DEMs are evaluated with GPS/levelling data. The impact of utilizing a high resolution SRTM DEM to improve the accuracy of the geoid model has been studied. Also, a density variation model has been established, and its effect on the accuracy of the geoid was investigated. Thereafter a new height datum for Iran was established based on the corrective surface idea. Finally, it was found that there is a significant correlation between the lateral geoid slope and the tectonic activities in Iran. We show that our hybrid gravimetric geoid model IRG04 agrees considerably better with GPS/levelling than any of the other recent local geoid models in the area. Its RMS fit with GPS/levelling is 27 cm and 3.8 ppm in the absolute and relative senses, respectively. Moreover, the relative accuracy of the IRG04 geoid model is at least 4 times better than any of the previously published global and regional geoid models in the area. Also, the RMS fit of the combined surface model (IRG04C) versus independent precise GPS/levelling is almost 4 times better compared to the original gravimetric geoid model (IRG04). These achievements clearly show the effect of the new gravity database and the SRTM data for the regional geoid determination in Iran based on the least-squares modification of Stokes’ formula. / <p>QC 20100906</p>
44

Film Formation and Surface Tension Studies of Powder Coatings

Adler, Jeanette January 2005 (has links)
<p>In industrial use of paint systems a swift processing is crucial. Another very important issue is to improve the quality of the final coating. This report investigates the film formation process of powder coatings, specially the spreading of individual powder particles. The obtained results can be used to understand and control the film formation process. In this way the desired levelling can be achieved and thus the desired gloss or other surface characteristics that may be required. This means that the method could be used when evaluating different polymer and additive combinations that could be used to change film formation behaviour or curing time for powder coating systems to suit various substrates. It makes it possible to avoid and minimize different surface defects as orange peel or cratering in the powder coated film.</p><p>We used a reflection optical microscope to better understand the film formation process and especially the spreading of a powder melt on surfaces with various surface energies. The obtained data were: the particle diameter, the area, area ratio and the contact angle of the powder particle as a function of time and temperature. This information can be used to derive the surface tension of any powder melt.</p><p>In this report we evaluate the dependencies of temperature, heat rate and surface energy for powder coatings on different substrates. The method provides information that can be used to optimize the film formation of a specific powder coating/substrate combination. This method can be used to evaluate the powder spreading and levelling on different substrates from a surface tension point of view.</p><p>We found, as expected, that the powder flows out on a hydrophilic surface and is inhibited by a hydrophobic. The increase of the area ratio on a hydrophilic surface was about five times as the initial area coverage and on a hydrophobic surface only two times the initial area coverage. The contact angle between the melted powder particle on the different surface types could be calculated. The melt surface tension could be calculated since three substrates surfaces with various surface energies were used. The melt surface tension was found to be about 18.5 mN/m.</p> / <p>Sammanfattning</p><p>Vid industriell användning av ett färgsystem är det viktigt med en snabb och smidig målningsprocess. En viktig del är att förbättra kvaliteten på den färdiga ytan. Denna rapport undersöker filmbildningsprocessen för pulverfärg, närmare bestämt spridningen av individuella pulverpartiklar. Resultaten från utvärderingen av denna metod kan användas för att bättre förstå och få kontroll över filmbildningsprocessen. Med denna undersökningsmetod kan den önskade utslätningen uppnås och därmed den önskade glansen eller annan yteffekt som kan vara önskvärd.</p><p>Metoden kan användas för att utvärdera olika polymer- och additivkombinationer som kan användas för att ändra filmbildningens uppförande eller bestämma härdningstiden för en pulverfärg att passa ett visst substrat. Metoden gör det möjligt att förhindra och minska olika ytdefekter såsom apelsinskals- eller kratereffekter i pulverfärgens yta.</p><p>Ett optiskt reflectionsmikroskop användes för att bättre kunna förstå filmbildningsprocessen och särskilt spridningen av smält pulver på substrat med olika ytenergier. De mätdata vi fick var partikeldiameter, area, areaförändring och kontaktvinkeln för pulverpartiklar som funktion av tid och temperatur. Ur denna information kunde pulversmältans ytenergier härledas.</p><p>I denna rapport utvärderas pulvrets beroende av temperatur, uppvärmning och ytenergi på olika substrat. Denna metod ger information som kan användas för att optimera filmbildningen av en specifik kombination av pulverfärg och substrat. Denna metod kan också användas för att utvärdera pulverspridning och utjämning av färgfilmen på olika substrat med avseende på ytenergierna.</p><p>Som förväntat flyter pulvret ut på hydrofila ytor och utflytningen ändras på en hydrofob yta. På en hydrofil yta sprider sig partikeln till fem gånger den ursprungliga arean över substratet och motsvarande två gånger för en hydrofob yta. Kontaktvinkeln mellan en smält pulverpartikel på olika sorters substrat från utförda mätningar beräknas utifrån utförda mätningar. Kontaktvinklar mellan pulver och olika substrat kan användas för att beräkna smältans ytspänning. Smältans ytspänning kan beräknas då experiment gjorts på tre sorters ytor med olika kända ytenergier. Smältans ytspänning var 18,5 mN/m.</p><p>Slutsatsen är att det går att observera och utvärdera resultaten av utsmältningsförloppet för pulverfärg med denna metod.</p>
45

Normalinių ir elipsoidinių aukščių sąsajos analizė (vakarų Lietuvoje) / The analysis of normal and ellipsoidal heights interrelation (Western Lithuania)

Zmitrovičienė, Danutė 30 June 2005 (has links)
Magistro baigiamajame darbe „Normalinių ir elipsoidinių aukščių sąsajos analizė (vakarų Lietuvoje) yra analizuojamas normalinių aukščių prognozės modeliai, sudaryti taikant kolokacijos metodą. Tam tikslui yra panaudojami 1-os klasės vertikaliojo tinklo GPS matavimų duomenys – punktų elpisoidiniai aukščiai bei jų koordinatės LKS 94 sistemoje ( vakarų Lietuvos dalyje). Prognozinio normalinio aukščio tikslumui įvertinti buvo panaudojami trys analizės variantai: taikant 5-ių, 6-ių ir 7-ių parametrų variantus. Įvertinama modelio kaita priklausomai nuo parametrų skaičiaus. Analizuojama klaidų įtaka prognozės modelio parametrų bei prognozinių normalinių aukščių tikslumui. / The thesis „The analysis of normal and ellipsoidal heights interrelation“ examines the making of the normal heights prognosis models, employing the Kolokation method. In that case, are used 1rst class vertical Lithuanian levelling network data measurements by GPS - point with elipsoidal heigts and their coordinates in the LKS 94 system (Western Lithuania). It was used three analysis variants for the evaluation of the accuracy of the prognostic normal heights: 5th, 6th, 7th parameters variants.This is performed by changing the sequence of the polynoms and elements of matrix of weights at elipsoidic and normal heights. The analysis of the influence of the prognostic model errors for the accuracy of the parametrs and prognostic normal heights.
46

Analyse et modélisation de l'effet des marées sur les réseaux de nivellement hydrostatiques du CERN

Boerez, Julien 21 February 2013 (has links) (PDF)
Les géomètres de la section Survey de l'Organisation Européenne pour la Recherche Nucléaire (CERN) utilisent le nivellement hydrostatique HLS pour effectuer des alignements verticaux précis. Le HLS atteint des précisions micrométriques, ce qui lui permet d'être utilisé pour les expériences à but de physique fondamentale comme le Large Hadron Collider (LHC). HLS mesure certes des déformations qui ont pour conséquence de désaligner tout accélérateur de particules lié au sol, mais il mesure également d'autres phénomènes aux caractéristiques bien particulières. Parmi ces phénomènes mesurés, les marées terrestres représentent une part très largement majoritaire du signal. Leur effet sur les mesures HLS est périodique et engendre une inclinaison longue base qui n'aboutit pas au désalignement relatif des aimants constitutifs d'un accélérateur. Les objectifs de ce doctorat sont de pouvoir prédire les effets ne perturbant pas l'alignement relatif d'un accélérateur de particules et ainsi corriger les mesures HLS de ces signaux. En effet, les tolérances planimétrique et altimétrique à respecter dans le domaine des accélérateurs de particules sont de plus en plus serrées. Par exemple, le Compact Linear Collider (CLIC), aujourd'hui à l'étude de faisabilité, nécessite une précision d'alignement à 3σ de 10 μm dans une fenêtre glissante de 200 m selon les directions transversale et verticale. Le HLS est candidat pour assurer cet alignement vertical mais l'amplitude de marée est d'environ +/-20 μm à 200 m, rendant nécessaire la prise en compte de ce phénomène longue base pour que l'instrumentation réponde aux besoins du CLIC. Ce doctorat est inspiré des travaux déjà réalisés sur les inclinomètres longue base et décrit les effets mesurés par HLS afin de classer ces phénomènes selon qu'ils désalignent ou non un accélérateur de particules. Enfin, les outils et modèles pour prédire les effets maitrisables sont utilisés pour anticiper les différents signaux mesurés par les HLS installés au CERN.
47

Testes sobre a eficiência do modelo do geopotencial EGM2008 na cidade de Porto Alegre

Nunes, Vagner Conceição January 2010 (has links)
Este estudo apresenta o teste da eficiência do Earth Global Model 2008 (EGM2008) na geração de um modelo geoidal local, através da compatiblização com a ondulação obtida por posicionamento GPS (Global Positioning System) em 63 Referências de Nível (RN’s) localizadas no município de Porto Alegre, Rio Grande do Sul. O objetivo geral da dissertação foi analisar a exatidão do modelo geoidal gerado a partir dos coeficientes do modelo geopotencial EGM2008 para nivelamento por GPS no município de Porto Alegre e os objetivos específicos foram: a avaliação do modelo na região de Porto Alegre, a comparação das ondulações geoidais do EGM2008 (NEGM2008) com as ondulações geoidais em 63 RN’s (NGPS), o ajustamento da componente sistemática do geoide que é a diferença entre NEGM2008 e NGPS e a geração do modelo geoidal local compatibilizado para Porto Alegre. O método adotado apresenta as seguintes etapas: cálculo das ondulações geoidais nas RN’s; eliminação de erros grosseiros; geração do modelo geoidal através dos dados do EGM2008 com resolução de 7” de arco; cálculo da componente sistemática do geoide; ajustamento da componente sistemática através de transformação por polinômio de 2° grau com seis parâmetros pelo Método dos Mínimos Quadrados (MMQ). Os resultados obtidos foram: os parâmetros que compatibilizam o modelo geoidal global com o local e modelo geoidal local compatibilizado no formato raster, contendo as ondulações geoidais para todo o município. O novo modelo apresentou erro médio de 1,9 cm e desvio padrão de 7,2 cm. Os resultados da dissertação confirmam que é possível reduzir o erro associado ao modelo global através dos procedimentos adotados. Dessa maneira, conclui que o método utilizado reduziu o valor médio da componente sistemática de 15,4 cm para 1,9 cm após o ajustamento. / This study presents the Earth Global Model 2008’s (EGM2008) efficiency test on the conception of a local geoid model. The results were acquired through the undulation compatibility obtained by GPS (Global Positioning System) in 63 Bench Mark (BM) located in Porto Alegre, Rio Grande do Sul state, Brazil. The aim of this research was to analyze the accuracy of the geoid model generated from the geopotential model EGM2008’s coefficients to GPS leveling in Porto Alegre. The specific goals were the evaluation of the model in Porto Alegre region’s, the comparison between the EGM2008 (NEGM2008) geoid undulations and the geoid undulations in 63 BM (NGPS), and the adjustment of geoid’s systematic component, that is the difference between NEGM2008 and NGPS and the local geoid model’s conception to Porto Alegre. The method used presents the following steps: geoid undulation on RN’s’s computation; elimination of gross errors; geoid model’s conception through EGM2008’s data with resolution of 7” of arch; geoid’s systematic component computation; adjustment of the systematic component through transformation of 2nd degree polynomial with six parameters by the method of Least Squares. The results were: the parameters that make the models global and local compatible, and local geoid model compatible in raster format, containing the geoid undulations for the entire municipality. The new model showed 1.9 of mean error and 7.2 cm of standard deviation. Through the procedures adopted, the dissertation results’ confirm that it is possible to reduce the error associated of the the global model. Therefore, the conclusion is that the method used reduced the mean error of the systematic component from 15,4 cm to 1.9 cm, after the adjustment.
48

Testes sobre a eficiência do modelo do geopotencial EGM2008 na cidade de Porto Alegre

Nunes, Vagner Conceição January 2010 (has links)
Este estudo apresenta o teste da eficiência do Earth Global Model 2008 (EGM2008) na geração de um modelo geoidal local, através da compatiblização com a ondulação obtida por posicionamento GPS (Global Positioning System) em 63 Referências de Nível (RN’s) localizadas no município de Porto Alegre, Rio Grande do Sul. O objetivo geral da dissertação foi analisar a exatidão do modelo geoidal gerado a partir dos coeficientes do modelo geopotencial EGM2008 para nivelamento por GPS no município de Porto Alegre e os objetivos específicos foram: a avaliação do modelo na região de Porto Alegre, a comparação das ondulações geoidais do EGM2008 (NEGM2008) com as ondulações geoidais em 63 RN’s (NGPS), o ajustamento da componente sistemática do geoide que é a diferença entre NEGM2008 e NGPS e a geração do modelo geoidal local compatibilizado para Porto Alegre. O método adotado apresenta as seguintes etapas: cálculo das ondulações geoidais nas RN’s; eliminação de erros grosseiros; geração do modelo geoidal através dos dados do EGM2008 com resolução de 7” de arco; cálculo da componente sistemática do geoide; ajustamento da componente sistemática através de transformação por polinômio de 2° grau com seis parâmetros pelo Método dos Mínimos Quadrados (MMQ). Os resultados obtidos foram: os parâmetros que compatibilizam o modelo geoidal global com o local e modelo geoidal local compatibilizado no formato raster, contendo as ondulações geoidais para todo o município. O novo modelo apresentou erro médio de 1,9 cm e desvio padrão de 7,2 cm. Os resultados da dissertação confirmam que é possível reduzir o erro associado ao modelo global através dos procedimentos adotados. Dessa maneira, conclui que o método utilizado reduziu o valor médio da componente sistemática de 15,4 cm para 1,9 cm após o ajustamento. / This study presents the Earth Global Model 2008’s (EGM2008) efficiency test on the conception of a local geoid model. The results were acquired through the undulation compatibility obtained by GPS (Global Positioning System) in 63 Bench Mark (BM) located in Porto Alegre, Rio Grande do Sul state, Brazil. The aim of this research was to analyze the accuracy of the geoid model generated from the geopotential model EGM2008’s coefficients to GPS leveling in Porto Alegre. The specific goals were the evaluation of the model in Porto Alegre region’s, the comparison between the EGM2008 (NEGM2008) geoid undulations and the geoid undulations in 63 BM (NGPS), and the adjustment of geoid’s systematic component, that is the difference between NEGM2008 and NGPS and the local geoid model’s conception to Porto Alegre. The method used presents the following steps: geoid undulation on RN’s’s computation; elimination of gross errors; geoid model’s conception through EGM2008’s data with resolution of 7” of arch; geoid’s systematic component computation; adjustment of the systematic component through transformation of 2nd degree polynomial with six parameters by the method of Least Squares. The results were: the parameters that make the models global and local compatible, and local geoid model compatible in raster format, containing the geoid undulations for the entire municipality. The new model showed 1.9 of mean error and 7.2 cm of standard deviation. Through the procedures adopted, the dissertation results’ confirm that it is possible to reduce the error associated of the the global model. Therefore, the conclusion is that the method used reduced the mean error of the systematic component from 15,4 cm to 1.9 cm, after the adjustment.
49

Testes sobre a eficiência do modelo do geopotencial EGM2008 na cidade de Porto Alegre

Nunes, Vagner Conceição January 2010 (has links)
Este estudo apresenta o teste da eficiência do Earth Global Model 2008 (EGM2008) na geração de um modelo geoidal local, através da compatiblização com a ondulação obtida por posicionamento GPS (Global Positioning System) em 63 Referências de Nível (RN’s) localizadas no município de Porto Alegre, Rio Grande do Sul. O objetivo geral da dissertação foi analisar a exatidão do modelo geoidal gerado a partir dos coeficientes do modelo geopotencial EGM2008 para nivelamento por GPS no município de Porto Alegre e os objetivos específicos foram: a avaliação do modelo na região de Porto Alegre, a comparação das ondulações geoidais do EGM2008 (NEGM2008) com as ondulações geoidais em 63 RN’s (NGPS), o ajustamento da componente sistemática do geoide que é a diferença entre NEGM2008 e NGPS e a geração do modelo geoidal local compatibilizado para Porto Alegre. O método adotado apresenta as seguintes etapas: cálculo das ondulações geoidais nas RN’s; eliminação de erros grosseiros; geração do modelo geoidal através dos dados do EGM2008 com resolução de 7” de arco; cálculo da componente sistemática do geoide; ajustamento da componente sistemática através de transformação por polinômio de 2° grau com seis parâmetros pelo Método dos Mínimos Quadrados (MMQ). Os resultados obtidos foram: os parâmetros que compatibilizam o modelo geoidal global com o local e modelo geoidal local compatibilizado no formato raster, contendo as ondulações geoidais para todo o município. O novo modelo apresentou erro médio de 1,9 cm e desvio padrão de 7,2 cm. Os resultados da dissertação confirmam que é possível reduzir o erro associado ao modelo global através dos procedimentos adotados. Dessa maneira, conclui que o método utilizado reduziu o valor médio da componente sistemática de 15,4 cm para 1,9 cm após o ajustamento. / This study presents the Earth Global Model 2008’s (EGM2008) efficiency test on the conception of a local geoid model. The results were acquired through the undulation compatibility obtained by GPS (Global Positioning System) in 63 Bench Mark (BM) located in Porto Alegre, Rio Grande do Sul state, Brazil. The aim of this research was to analyze the accuracy of the geoid model generated from the geopotential model EGM2008’s coefficients to GPS leveling in Porto Alegre. The specific goals were the evaluation of the model in Porto Alegre region’s, the comparison between the EGM2008 (NEGM2008) geoid undulations and the geoid undulations in 63 BM (NGPS), and the adjustment of geoid’s systematic component, that is the difference between NEGM2008 and NGPS and the local geoid model’s conception to Porto Alegre. The method used presents the following steps: geoid undulation on RN’s’s computation; elimination of gross errors; geoid model’s conception through EGM2008’s data with resolution of 7” of arch; geoid’s systematic component computation; adjustment of the systematic component through transformation of 2nd degree polynomial with six parameters by the method of Least Squares. The results were: the parameters that make the models global and local compatible, and local geoid model compatible in raster format, containing the geoid undulations for the entire municipality. The new model showed 1.9 of mean error and 7.2 cm of standard deviation. Through the procedures adopted, the dissertation results’ confirm that it is possible to reduce the error associated of the the global model. Therefore, the conclusion is that the method used reduced the mean error of the systematic component from 15,4 cm to 1.9 cm, after the adjustment.
50

Měření posunů a přetvoření mostu Gagarin / Deformation Measurement of Gagarin Bridge

Czíria, Kornél January 2016 (has links)
The work deals with a complex analysis of displacements and deformations of one bridge span of the railway bridge "Gagarin". The bridge structure was since 2009 annually measured. In addition to long-term monitoring of the bridge a 24-hour automatized monitoring was conducted in 2015 using robotic total station. The results of monitoring enables the analysis of displacements and deformations, analysis of measurement accuracy and also environmental influences on the structure - determination of the temperature dependence of deformations. Another part of the work is evaluating the long-term stability of the height reference frame that was used for geodetic epoch measuring of the bridge columns. The results of the work are the values of detected displacements and deformations, their graphical illustration, geometric interpretation and relevant characteristics of accuracy.

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