The need to compactly represent 3D data is motivated by the ever-increasing size of these data. Furthermore, for large data sets it is useful to randomly access and process a small part of the data. In this thesis we propose two methods of compactly representing 3D data while allowing random access. The first is the multiresolution sphere-packing tree (MSP-tree). The MSP-tree is a multiresolution 3D hierarchy on regular grids based on sphere-packing arrangements. The grids of the MSP-tree compactly represent underlying point-sampled data by using more efficient grids than existing methods while maintaining high granularity and a hierarchical structure that allows random access. The second is distance-ranked random-accessible mesh compression (DR-RAMC). DR-RAMC is a lossless simplicial mesh compressor that allows random access and decompression of the mesh data based on a spatial region-of-interest. DR-RAMC encodes connectivity based on relative proximity of vertices to each other and organizes both this proximity data and vertex coordinates using a k-d tree. DR-RAMC is insensitive to a variety of topological mesh problems (e.g. holes, handles, non-orientability) and can compress simplicial meshes of any dimension embedded in spaces of any dimension. Testing of DR-RAMC shows competitive compression rates for triangle meshes and first-ever random accessible compression rates for tetrahedral meshes. / Thesis (Ph.D, Computing) -- Queen's University, 2012-07-17 15:28:39.406

No / In this paper we discuss techniques for 3D data modelling and processing where the data are usually provided as point clouds which arise from 3D scanning devices. The particular approaches we adopt in modelling 3D data involves the use of Partial Differential Equations (PDEs). In particular we show how the continuous and discrete versions of elliptic PDEs can be used for data modelling. We show that using PDEs it is intuitively possible to model data corresponding to complex scenes. Furthermore, we show that data can be stored in compact format in the form of PDE boundary conditions. In order to demonstrate the methodology we utlise several examples of practical nature.

Record keeping and management of electrical utilities inside buildings is an important aspect to ensure effective electrical distribution. The ability to find the location of each electrical feature inside a building and extract information about it helps to solve network problems faster. The use of a spatial database structure facilitates the maintenance and general operations of an electrical network across different buildings. The aim of this study is to design and develop a 3D data model to provide a management system for electrical utilities inside buildings. The geodatabase provides integrated information between different electrical components forming the network inside the specified buildings in the study area. A prototype called the PUK geodatabase was designed and developed for the NWU Potchefstroom Campus as a 3D data model. The data model consists of raster and vector data used in network datasets, relationship classes and topology rules. The aim of this project was accomplished through the 3D analysis capabilities of the model. The research determined that the prototype called the PUK geodatabase can be utilized as a 3D management system for electrical utilities across the different floor levels of a building. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2012

Baigiamajame magistro darbe nagrinėjama požeminių komunikacijų vizualizacija trimačiame modelyje. Šiame magistriniame darbe išnagrinėta 3D duomenų svarba ir pranašumas prieš 2D vizualizavimą. Buvo atliktas požeminių komunikacijų projektavimo tyrimas trima��io vaizdavimo programine įranga, ištirtas šių technologijų naudojimas užsienyje bei naudojimo perspektyvos Lietuvoje. Darbą sudaro 10 dalių: įvadas, informacijos vizualizavimo aplinkos, 3D duomenų modelio esmė, 3D programinės įrangos galimybės inžinerijoje,3D vizualizavimo programinė įranga,3D modeliavimo koordinačių sistemos, trimačio geoinformacinių sistemų modelio sudarymas, požeminių komunikacijų trimačio geoinformacinių sistemų modelio sudarymo metodika, požeminių komunikacijų duomenų surinkimo reikalavimai, požeminių komunikacijų 3D skaitmeninio modelio kūrimas, požeminių komunikacijų trimačio modelio naudojimas Lietuvoje ir pasaulyje,išvados, literatūros sąrašas. / In the magistrate thesis are researching visualization of Underground communications at 3D data model. In the thesis analyse 3D model data significance and advantage against 2D model data. Also researching program equipment projection of Underground communications 3D data model, technology usage in foreign countries and opportunities for use in Lithuania. Structure: introduction, information visualization surrounding, 3D data model essence, 3D data program equipment opportunity in the engineering, 3D data model equipment, 3D data model coordinate systems, 3D data model formation, formation model of underground communication at 3D data model, data assemblage standards of underground communications, underground communication 3D data model creation, 3D data model usage in the world and Lithuania, conclusions, references.

Record keeping and management of electrical utilities inside buildings is an important aspect to ensure effective electrical distribution. The ability to find the location of each electrical feature inside a building and extract information about it helps to solve network problems faster. The use of a spatial database structure facilitates the maintenance and general operations of an electrical network across different buildings. The aim of this study is to design and develop a 3D data model to provide a management system for electrical utilities inside buildings. The geodatabase provides integrated information between different electrical components forming the network inside the specified buildings in the study area. A prototype called the PUK geodatabase was designed and developed for the NWU Potchefstroom Campus as a 3D data model. The data model consists of raster and vector data used in network datasets, relationship classes and topology rules. The aim of this project was accomplished through the 3D analysis capabilities of the model. The research determined that the prototype called the PUK geodatabase can be utilized as a 3D management system for electrical utilities across the different floor levels of a building. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2012

L'analyse de la démarche clinique est généralement subjective, étant effectuée par des cliniciens observant la démarche des patients. Des alternatives à une telle analyse sont les systèmes basés sur les marqueurs et les systèmes basés sur les plates-formes au sol. Cependant, cette analyse standard de la marche nécessite des laboratoires spécialisés, des équipements coûteux et de longs délais d'installation et de post-traitement. Les chercheurs ont fait de nombreuses tentatives pour proposer une alternative basée sur la vision par ordinateur pour l'analyse de la demarche. Avec l'apparition de caméras 3D bon marche, le problème de l'évaluation qualitative de la démarche a été re-examiné. Les chercheurs ont réalisé le potentiel des dispositifs de cameras 3D pour les applications d'analyse de mouvement. Cependant, malgré des progrès très encourageants dans les technologies de détection 3D, leur utilisation réelle dans l'application clinique reste rare.Cette thèse propose des modèles et des techniques pour l'évaluation du mouvement à l'aide d'un capteur Microsoft Kinect. En particulier, nous étudions la possibilité d'utiliser différentes données fournies par une caméra RGBD pour l'analyse du mouvement et de la posture. Les principales contributions sont les suivantes. Nous avons réalisé une étude de l'etait de l'art pour estimer les paramètres importants de la démarche, la faisabilité de différentes solutions techniques et les méthodes d'évaluation de la démarche existantes. Ensuite, nous proposons un descripteur de posture basé sur un nuage de points 3D. Le descripteur conçu peut classer les postures humaines statiques a partir des données 3D. Nous construisons un système d'acquisition à utiliser pour l'analyse de la marche basée sur les donnees acquises par un capteur Kinect v2. Enfin, nous proposons une approche de détection de démarche anormale basée sur les données du squelette. Nous démontrons que notre outil d'analyse de la marche fonctionne bien sur une collection de données personnalisées et de repères existants. Notre méthode d'évaluation de la démarche affirme des avances significatives dans le domain, nécessite un équipement limité et est prêt à être utilisé pour l'évaluation de la démarche. / Clinical Gait analysis is traditionally subjective, being performed by clinicians observing patients gait. A common alternative to such analysis is markers-based systems and ground-force platforms based systems. However, this standard gait analysis requires specialized locomotion laboratories, expensive equipment, and lengthy setup and post-processing times. Researchers made numerous attempts to propose a computer vision based alternative for clinical gait analysis. With the appearance of commercial 3D cameras, the problem of qualitative gait assessment was reviewed. Researchers realized the potential of depth-sensing devices for motion analysis applications. However, despite much encouraging progress in 3D sensing technologies, their real use in clinical application remains scarce.In this dissertation, we develop models and techniques for movement assessment using a Microsoft Kinect sensor. In particular, we study the possibility to use different data provided by an RGBD camera for motion and posture analysis. The main contributions of this dissertation are the following. First, we executed a literature study to estimate the important gait parameters, the feasibility of different possible technical solutions and existing gait assessment methods. Second, we propose a 3D point cloud based posture descriptor. The designed descriptor can classify static human postures based on 3D data without the use of skeletonization algorithms. Third, we build an acquisition system to be used for gait analysis based on the Kinect v2 sensor. Fourth, we propose an abnormal gait detection approach based on the skeleton data. We demonstrate that our gait analysis tool works well on a collection of custom data and existing benchmarks. Weshow that our gait assessment approach advances the progress in the field, is ready to be used for gait assessment scenario and requires a minimum of the equipment.

Fingerprints are the most accurate and widely used biometrics for human identification due to their uniqueness, rapid and easy means of acquisition. Contact based techniques of fingerprint acquisition like traditional ink and live scan methods are not user friendly, reduce capture area and cause deformation of fingerprint features. Also, improper skin conditions and worn friction ridges lead to poor quality fingerprints. A non-contact, high resolution, high speed scanning system has been developed to acquire a 3D scan of a finger using structured light illumination technique. The 3D scanner system consists of three cameras and a projector, with each camera producing a 3D scan of the finger. By merging the 3D scans obtained from the three cameras a nail to nail fingerprint scan is obtained. However, the scans from the cameras do not merge perfectly. The main objective of this thesis is to calibrate the system well such that 3D scans obtained from the three cameras merge or align automatically. This error in merging is reduced by compensating for radial distortion present in the projector of the scanner system. The error in merging after radial distortion correction is then measured using the projector coordinates of the scanner system.

One of the challenging problems in geometric modeling and computer graphics is the construction of realistic human facial geometry. Such geometry are essential for a wide range of applications, such as 3D face recognition, virtual reality applications, facial expression simulation and computer based plastic surgery application. This paper addresses a method for the construction of 3D geometry of human faces based on the use of Elliptic Partial Differential Equations (PDE). Here the geometry corresponding to a human face is treated as a set of surface patches, whereby each surface patch is represented using four boundary curves in the 3-space that formulate the appropriate boundary conditions for the chosen PDE. These boundary curves are extracted automatically using 3D data of human faces obtained using a 3D scanner. The solution of the PDE generates a continuous single surface patch describing the geometry of the original scanned data. In this study, through a number of experimental verifications we have shown the efficiency of the PDE based method for 3D facial surface reconstruction using scan data. In addition to this, we also show that our approach provides an efficient way of facial representation using a small set of parameters that could be utilized for efficient facial data storage and verification purposes.

Rapporten går ut på att se om laserskanning är en bra metod att använda sig av vid ombyggnation, tillbyggnad och renovering. För att få fram ett svar på detta har två takbalkar i Södra Climate Arena skannats av. Vid genomförandet användes en laserskanner från Leica av varianten P30. Försöket innehåller fyra stycken uppställningar som riktas mot sex stycken måltavlor. Informationen som fåtts ut från skanningen i form av en sektion i AutoCAD har jämförts med befintliga ritningar för att se om informationen från skanningen stämmer överens med ritningarna. I modellen som fåtts ut från försöket har också mätning och undersökning skett för att se hur bra det går att mäta i modellen och om det är något som fungerar lätt att använda sig av i praktiken. Arbetet går även ut på att få en god inblick i hur laserskannern Leica P30 fungerar.

<p>Ova doktorska teza se bavi proučavanjem i razvojem paralelnih<br />algoritama za transponovanje distribuiranih trodimenzionalnih<br />struktura podataka, kao i implementacijom ovih algoritama u okviru<br />C/OpenMP/MPI programske paradigme. Razvijena implementacija je<br />primenjena na rešavanje nelinearne parcijalne diferencijealne<br />jednačine Šredingerovog tipa (Gros-Pitaevski jednačina) korišćenjem<br />Krenk-Nikolson metoda, a u okviru teze je predstavljen ciklus razvoja<br />odgovarajućeg softvera, kao i rezultati testova validnosti i merenja<br />performansi dobijenih na računarskom klasteru.</p> / <p>This thesis studies and develops parallel algorithms for transposing<br />distributed three-dimensional data structures, and describes their technical<br />implementation in C/OpenMP/MPI programing paradigm. The developed<br />implementation is applied for solving of nonlinear partial differential equation<br />of the Schroedinger type (Gross-Pitaevskii equation) using Crank-Nicolson<br />method. The thesis presents the corresponding software development cycle,<br />as well as results of validity tests and performance measurements obtained<br />on a computer cluster.</p>