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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

Procedural reconstruction of architectural parametric models from airborne and ground laser scans

Edum-Fotwe, Kwamina January 2018 (has links)
This research addresses the problem of efficiently and robustly reconstructing semantically-rich 3D architectural models from laser-scanned point-clouds. It first covers the pre-existing literature and industrial developments in active-sensing, 3D reconstruction of the built-environment and procedural modelling. It then documents a number of novel contributions to the classical problems of change-detection between temporally varying multi-modal geometric representations and automatic 3D asset creation from airborne and ground point-clouds of buildings. Finally this thesis outlines on-going research and avenues for continued investigation - most notably fully automatic temporal update and revision management for city-scale CAD models via data-driven procedural modelling from point-clouds. In short this thesis documents the outcomes of a research project whose primary aim was to engineer fast, accurate and sparse building reconstruction algorithms. Formally: this thesis puts forward the hypothesis (and advocates) that architectural reconstruction from actively-sensed point-clouds can be addressed more efficiently and affording greater control (over the geometric results) - via deterministic procedurally-driven analysis and optimisation than via stochastic sampling.
2

Quantitative Comparison of Lidar Data and User-generated Three-dimensional Building Models From Google Building Maker

Liu, Yang 08 1900 (has links)
Volunteered geographic information (VGI) has received increased attention as a new paradigm for geographic information production, while light detection and ranging (LiDAR) data is widely applied to many fields. This study quantitatively compares LiDAR data and user-generated 3D building models created using Google Building Maker, and investigate the potential applications of the quantitative measures in support of rapid disaster damage assessment. User-generated 3D building models from Google Building Maker are compared with LiDAR-derived building models using 3D shape signatures. Eighteen 3D building models are created in Fremont, California using the Google Building Maker, and six shape functions (distance, angle, area, volume, slope, and aspect) are applied to the 18 LiDAR-derived building models and user-generated ones. A special case regarding the comparison between LiDAR data and building models with indented walls is also discussed. Based on the results, several conclusions are drawn, and limitations that require further study are also discussed.
3

Adaptable Three Dimensional System for Building Inspection Management

Abou Shaar, Belal January 2012 (has links)
Sustaining the safety and operability of civil infrastructure assets, including buildings, is a complex undertaking that requires a perpetual cycle involving inspection, and further decisions for renewal fund allocation. However, inspection, which is the basis for all subsequent decisions, is a complex task to manage, particularly when a large number of assets are involved. The current lack of a structured process with visual referencing as well as the high subjectivity and inflexibility to changing inspection requirements make current inspections very costly and time consuming. This research improves the building inspection process by introducing a 3D system for inspection management that has four unique features: (1) a structured assessment approach that considers multiple organizations, buildings and inspectors, using a GIS interface; (2) a 3D visual referencing method for marking problem areas during inspections to facilitate all on-site inspections, thus reducing time and cost; (3) a visual guidance module to reduce inspection subjectivity; and (4) a flexible module for designing different assessment types. The proposed inspection management system creates 3D building plans from 2D Computer-Aided Drawing (CAD) to provide location referencing that enhances inspection effectiveness. The visual guidance system allows inspectors with various experience levels to perform consistent inspections and requires less training, thus reducing costs. Flexible inspection generation also allows a variety of inspection types, such as condition and level of service, to be readily incorporated. A computerized prototype system has been developed using the Windows Presentation Foundation’s XAML markup language with underlying C# programming on a tablet computer for experimentation. The thesis provides a detailed description of system development and reports the benefits of the system on a sample inspection. Accordingly, the system has proven most useful for large organizations that own a large number of building assets that require frequent inspections.
4

Adaptable Three Dimensional System for Building Inspection Management

Abou Shaar, Belal January 2012 (has links)
Sustaining the safety and operability of civil infrastructure assets, including buildings, is a complex undertaking that requires a perpetual cycle involving inspection, and further decisions for renewal fund allocation. However, inspection, which is the basis for all subsequent decisions, is a complex task to manage, particularly when a large number of assets are involved. The current lack of a structured process with visual referencing as well as the high subjectivity and inflexibility to changing inspection requirements make current inspections very costly and time consuming. This research improves the building inspection process by introducing a 3D system for inspection management that has four unique features: (1) a structured assessment approach that considers multiple organizations, buildings and inspectors, using a GIS interface; (2) a 3D visual referencing method for marking problem areas during inspections to facilitate all on-site inspections, thus reducing time and cost; (3) a visual guidance module to reduce inspection subjectivity; and (4) a flexible module for designing different assessment types. The proposed inspection management system creates 3D building plans from 2D Computer-Aided Drawing (CAD) to provide location referencing that enhances inspection effectiveness. The visual guidance system allows inspectors with various experience levels to perform consistent inspections and requires less training, thus reducing costs. Flexible inspection generation also allows a variety of inspection types, such as condition and level of service, to be readily incorporated. A computerized prototype system has been developed using the Windows Presentation Foundation’s XAML markup language with underlying C# programming on a tablet computer for experimentation. The thesis provides a detailed description of system development and reports the benefits of the system on a sample inspection. Accordingly, the system has proven most useful for large organizations that own a large number of building assets that require frequent inspections.
5

Zaměření rodinného domu v Brně Žabovřeskách / Surveying of family house in Brno Žabovřesky locality

Chládeková, Paulína January 2020 (has links)
This diploma thesis is about measuring of family house, creating drawings and visualization of results. The family house is located in the Brno-Žabovřesky The house was surveyed by the classical geodetic method using a survey net built using GNSS (Global Navigation Satellite System). The results of field measurements were processed in the Groma program, graphic outputs (footprints of individual floors, sections and 3D model) in the MicroStation application. The documentation can be used mainly for the planned reconstruction of the family house and other related purposes.
6

Systém pro tvorbu 3D modelů budov z půdorysů / System for Modelling of 3D Buildings from Floor Plans

Jurka, Zdeněk January 2012 (has links)
This work deals with description and design of application for generating 3D building models from floor plans and their publication on the Internet. First chapter describes methods used for floor plans creation. Next part describes how are foor plans transformed into three-dimensional model. Following chapters describes implementation details concerning application used for creation of building floor plan and three-dimensional model generation. Work also covers implementation of web based application for viewing models in web browser. Final chapters sums up results and limitations of described solution. There are also discussed possible extensions of current project.
7

Aplicação da teoria de confiabilidade na análise estrutural de edifícios considerando a interação solo-estrutura. / Application of the structural reliability theory in the structural analysis of building considering soil-structure interaction.

Ribeiro, Mauricio Rogerio Ramos 12 February 2019 (has links)
O trabalho propõe avaliação das respostas de esforços e deslocamentos de edifícios 3D considerando a interação solo-fundação-estrutura usando o conceito de Confiabilidade Estrutural. Para isso, empregam-se os Métodos dos Elementos Finitos (MEF) para a análise de estruturas e os métodos de Monte Carlo Simples (MCS) e First Order Second Moment (FOSM) para calcular sua segurança perante a inserção de variabilidade em certos parâmetros significativos no projeto, como as incertezas dos dados de rigidez do solo e a velocidade de vento. A formulação do edifício é baseada no MEF com elementos de barra e de casca, sendo as vigas, pilares e estacas elementos de barra e as sapatas em elementos de casca. Essa formulação é elastostática, mas permitindo a analise não-linear geométrica para os pilares. O solo é representado pelo modelo discreto de Winkler, o qual substitui sua influência contínua por molas pontuais com rigidezes equivalentes, tanto para a fundação rasa (sapatas isoladas) como para profunda (estacas). Com os resultados obtidos pelos modelos gerados, são feitas discussões e comparações com os métodos tradicionais de avaliação do fenômeno de recalque diferencial confrontando limites de índices de confiabilidade apresentados no Joint Committee on Structural Safety (JCSS, 2001) e os valores absolutos propostos pela literatura com base na Associação Brasileira de Normas Técnicas, ABNT, NBR6122: Projeto e execução de fundações (2010). Realiza-se também a análise de Estado Limite Último de pilares submetidos a flexo-compressão oblíqua com não linearidade física, de modo a avaliar o dimensionamento com fatores de segurança parciais da NBR 8681: Ações e segurança nas estruturas - Procedimento (2004) e Métodos de Confiabilidade Estrutural. / This work proposes the evaluation for the effects of forces and displacements about 3D buildings considering the soil-foundation-structure interaction using the concept of Structural Reliability. To do so, it is applied the Finite Elements Method (FEM) for the structural analysis and Simple Monte Carlo Method (SMC) and the First Order Second Moment (FOSM) to calculate its safety towards the application of variability at certain significant parameters of the project, as the uncertainness about the data of soil stiffness and wind speed. The building\'s formulation is based on the FEM with framed bars and shell elements, being beams, columns and piles as beam elements and the footings as shell elements. That formulation is elastostatic, although permits a non-linear geometric analysis for the columns. The soil is represented by the discrete Winkler\'s model, in which substitutes its continuum influence by nodal springs with equivalent stiffness, such as for shallow foundations (isolated footings), as for deep foundations (piles). With the results obtained by the generated models, discussions are done and comparisons about traditional method to evaluate the phenomenon of the differential settlement confronting the limits of the reliability presents in the Joint Committee on Structural Safety (JCSS,2001) and the absolute values proposed by the literature based on the Brazilian Association of Technical Standards, ABNT, NBR6122: Project and execution of foundations (2010). An analysis about the Ultimate Limit State of columns submitted by flexo-compression with physical non-linearity it is also performed, so that to compare the design with partial safety factors of the NBR 8681: Action and safety on structures - Proceedings (2004) and structural reliability methods.
8

Investigation of ways to semi-automatically extract 3D buildings : Based on using open data of buildings in Sweden

Gente, Jonathan January 2024 (has links)
This thesis is dedicated to contributing to the field of semi-automatic extraction of 3D buildings in level of detail 2 (LOD2). The data used in the thesis is open data available in Sweden, such as building footprints from local municipalities and national light detection and ranging (LiDAR) data. The study site is a part of a central street of the city Gävle, Sweden. To perform the automatic extraction of 3D buildings the software ArcGIS PRO and its solution for 3D buildings was used. The method consists of experimenting with the segmentation of the building footprints and then comparing the resulting models RMSE as a whole and for two specific buildings of different size (one small and one large building). There are some improvements that can be made in the quality assessment of the 3D models as the method used in this thesis bases the RMSE of the 3D models the obtained digital surface model (DSM). One possible way to improve the quality assessment would have been to perform a field survey to gather reference points with lower uncertainties than the DSM e.g. employing a total station. The conclusions of the thesis identify key settings that affects the 3D modelling. The best model, lowest RMSE, achieved an RMSE of 2.36 meters with tuning the setting of spatial detailwhile the rest of the settings were kept at their default values. Furthermore, the thesis identifies that the regularization tolerance setting, when segmenting the building footprints, affects the 3D models of large buildings negatively, as seen in an increase of RMSE when it is set to 0.5 meters and lower. However, further studies are required on a larger scale to better validate the conclusions.
9

BYGGNADSTEKNISKA LÖSNINGAR VID PÅBYGGNAD AV BOSTÄDER PÅ PARKERINGSHUS / BUILDING ENGINEERING SOLUTIONS FOR ADDITIONAL FLOORS OF HOUSING ON PARKING GARAGES

Lans, Stina, Jakobsson, Albin January 2019 (has links)
Syfte: I Sverige råder det en stor bostadsbrist. En lösning för att skapa nya bostäder i tätbebyggda områden är vertikal förtätning. Detta kan ske via våningspåbyggnad av bostäder på parkeringshus. Denna typ av påbyggnad ställer dock krav på den befintliga byggnaden. Rapportens syfte är att fungera som ett underlag vid projektering av konstruktion, brand och installationer vid framtida projekt av liknande slag. Målet är vidare att analysera och sammanställa olika byggnadstekniska lösningar som används vid våningspåbyggnad av bostäder på parkeringshus. Detta skall besvaras genom följande frågeställningar: Vilka konstruktionstyper tillämpas vid våningspåbyggnad på ett parkeringshus och vilka krav ställer påbyggnaden på den befintliga stommen? Vilka brandkrav ställs på denna typ av våningspåbyggnad och hur uppfylls dessa? Hur förses påbyggnaden med installationer?   Metod: Rapporten bygger på en kvalitativ fallstudie där intervjuer och dokumentanalyser legat till grund för empirin. För att styrka studien med teori har en litteraturstudie genomförts.   Resultat: Resultatet visar att en lätt stomme har använts till samtliga våningspåbyggnader, däremot har valet av stommaterial skiljt sig åt. Kapaciteten på den befintliga byggnadens grund har varit avgörande för om en våningspåbyggnad varit möjlig. Placering av våningspåbyggnaden har berott på om boyta eller antalet parkeringsplatser prioriterats högst. Brandkraven på denna typ av byggnad kan likställas med kraven som ställs på en nybyggnad av bostäder. Detta har inneburit att förändringar på de befintliga parkeringshusen varit nödvändiga för att uppfylla kraven. Nya installationsschakt har placerats både in- och utvändigt av den befintliga byggnaden.   Konsekvenser: De slutsatser och rekommendationer, utifrån rapportens innehåll, består främst av vikten i att göra en noggrann inventering av den befintliga byggnaden. Det handlar om byggnadens kapacitet och vilka eventuella förstärkningsarbeten som krävs innan en våningspåbyggnad.   Begränsningar: Studien avgränsar sig från byggnadstekniska beräkningar och ekonomiska kalkyler. Arbetet har begränsats utifrån en viss mängd ord och tidsram, utan dessa hade möjligheten funnits att göra en mer djupgående analys av studiens referensobjekt. Detta genom att intervjua ytterligare aktörer inom fler konsultområden för de valda referensobjekten. / Purpose: In Sweden, there is a shortage of housing and a solution for creating new housing in urban areas is vertical densification. Vertical densification can be done by adding floors of housing on top of existing parking garages. This type of extension sets demands on the existing building. The purpose of this thesis is to serve as a basis for the planning of construction, fire requirements and installations for future similar projects. The goal is furthermore to analyze and compile various building-technical solutions that are used when floors of housing are built on top of existing parking garages. The goal is answered by the following questions: Which types of construction are used for additional floors of housing on top of parking garages and what requirements does the extension have on the existing building? What fire requirements are imposed on this type of extension and how are they fulfilled? How are the additional floors of housing provided with installations?   Method: The report is based on a qualitative case study in which interviews and document analysis formed the basis of empirical data. To confirm the study with theory, a literature study has been conducted. Findings: The result shows that a light framework has been used for additional floors of housing, however, the choice of framework material has been different. The capacity of the existing building's foundation has been vital for whether an extension with housing has been possible. Placement of the extension has been due to whether the living space or the number of parking spaces is given as the highest priority. The fire requirements for this type of building can be equated with the requirements imposed on a new building of housing. This has meant that changes to the existing parking garages have been necessary to meet the requirements. New shafts for installations have been placed on both inside and outside of the existing building. Implications: The conclusions and recommendations, based on the content of the thesis, consist primarily of the importance of making an accurate inventory. It’s about the existing building's capacity and what possible reinforcement work it requires before an extension with housing. Limitations: The study delimits itself from construction engineering calculations and economic calculations. The work has been limited based on a variety of words and timeframe, without these it would be possible to make a more in-depth analysis of the study's reference objects. This would be done through interviewing more actors from additional consulting areas for the selected reference objects.
10

An Approach to 3D Building Model Reconstruction from Airborne Laser Scanner Data Using Parameter Space Analysis and Fusion of Primitives / Eine Methode zur Rekonstruktion von 3D Gebäudemodellen aus Flugzeuglaserscannerdaten unter der Verwendung von Parameterräumen und der Fusion von Primitiven

Hofmann, Alexandra 05 August 2005 (has links) (PDF)
Within this work an approach was developed, which utilises airborne laser scanner data in order to generate 3D building models. These 3D building models may be used for technical and environmental planning. The approach has to follow certain requirements such as working automatically and robust and being flexible in use but still practicable. The approach starts with small point clouds containing one building at the time extracted from laser scanner data set by applying a pre-segmentation scheme. The laser scanner point cloud of each building is analysed separately. A 2.5D-Delaunay triangle mesh structure (TIN) is calculated into the laser scanner point cloud. For each triangle the orientation parameters in space (orientation, slope and perpendicular distance to the barycentre of the laser scanner point cloud) are determined and mapped into a parameter space. As buildings are composed of planar features, primitives, triangles representing these features should group in parameter space. A cluster analysis technique is utilised to find and outline these groups/clusters. The clusters found in parameter space represent plane objects in object space. Grouping adjacent triangles in object space - which represent points in parameter space - enables the interpolation of planes in the ALS points that form the triangles. In each cluster point group a plane in object space is interpolated. All planes derived from the data set are intersected with their appropriate neighbours. From this, a roof topology is established, which describes the shape of the roof. This ensures that each plane has knowledge on its direct adjacent neighbours. Walls are added to the intersected roof planes and the virtual 3D building model is presented in a file written in VRML (Virtual Reality Macro Language). Besides developing the 3D building model reconstruction scheme, this research focuses on the geometric reconstruction and the derivation of attributes of 3D building models. The developed method was tested on different data sets obtained from different laser scanner systems. This study will also show, which potential and limits the developed method has when applied to these different data sets. / In der vorliegenden Arbeit wird eine neue Methode zur automatischen Rekonstruktion von 3D Gebäudemodellen aus Flugzeuglaserscannerdaten vorgestellt. Diese 3D Gebäudemodelle können in technischer und landschaftsplanerischer Hinsicht genutzt werden. Bezüglich der zu entwickelnden Methode wurden Regelungen und Bedingungen erstellt, die eine voll automatische und robuste Arbeitsweise sowie eine flexible und praktikable Nutzung gewährleisten sollten. Die entwickelte Methode verwendet Punktwolken, welche mittels einer Vorsegmentierung aus dem gesamten Laserscannerdatensatz extrahiert wurden und jeweils nur ein Gebäude beinhalten. Diese Laserscannerdatenpunktwolken werden separat analysiert. Eine 2,5D-Delaunay-Dreiecksvermaschung (TIN) wird in jede Punktwolke gerechnet. Für jedes Dreieck dieser Vermaschung werden die Lageparameter im Raum (Ausrichtung, Neigungsgrad und senkrechter Abstand der Ebene des Dreiecks zum Schwerpunkt der Punktwolke) bestimmt und in einen Parameterraum aufgetragen. Im Parameterraum bilden diejenigen Dreiecke Gruppen, welche sich im Objektraum auf ebenen Flächen befinden. Mit der Annahme, dass sich ein Gebäude aus ebenen Flächen zusammensetzt, dient die Identifizierung von Clustern im Parameterraum der Detektierung dieser Flächen. Um diese Gruppen/Cluster aufzufinden wurde eine Clusteranalysetechnik genutzt. Über die detektierten Cluster können jene Laserscannerpunkte im Objektraum bestimmt werden, die eine Dachfläche formen. In die Laserscannerpunkte der somit gefundenen Dachflächen werden Ebenen interpoliert. Alle abgeleiteten Ebenen gehen in den entwickelten Rekonstruktionsalgorithmus ein, der eine Topologie zwischen den einzelnen Ebenen aufbaut. Anhand dieser Topologie erhalten die Ebenen ?Kenntnis? über ihre jeweiligen Nachbarn und können miteinander verschnitten werden. Der fertigen Dachgestalt werden Wände zugefügt und das komplette 3D Gebäudemodell wird mittels VRML (Virtual Reality Macro Language) visualisiert. Diese Studie bezieht sich neben der Entwicklung eines Schemas zu automatischen Gebäuderekonstruktion auch auf die Ableitung von Attributen der 3D Gebäudemodellen. Die entwickelte Methode wurde an verschiedenen Flugzeuglaserscannerdatensätzen getestet. Es wird gezeigt, welche Potentiale und Grenzen die entwickelte Methode bei der Bearbeitung dieser verschiedenen Laserscannerdatensätze hat.

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