High performance computer simulated bronchoscopy with interactive navigation.

by Ping-Fu Fung.Thesis (M.Phil.)--Chinese University of Hong Kong, 1998.Includes bibliographical references (leaves 98-102).Abstract also in Chinese.Abstract --- p.ivAcknowledgements --- p.viChapter 1 --- Introduction --- p.1Chapter 1.1 --- Medical Visualization System --- p.4Chapter 1.1.1 --- Data Acquisition --- p.4Chapter 1.1.2 --- Computer-aided Medical Visualization --- p.5Chapter 1.1.3 --- Existing Systems --- p.6Chapter 1.2 --- Research Goal --- p.8Chapter 1.2.1 --- System Architecture --- p.9Chapter 1.3 --- Organization of this Thesis --- p.10Chapter 2 --- Volume Visualization --- p.11Chapter 2.1 --- Sampling Grid and Volume Representation --- p.11Chapter 2.2 --- Priori Work in Volume Rendering --- p.13Chapter 2.2.1 --- Surface VS Direct --- p.14Chapter 2.2.2 --- Image-order VS Object-order --- p.18Chapter 2.2.3 --- Orthogonal VS Perspective --- p.22Chapter 2.2.4 --- Hardware Acceleration VS Software Acceleration --- p.23Chapter 2.3 --- Chapter Summary --- p.29Chapter 3 --- IsoRegion Leaping Technique for Perspective Volume Rendering --- p.30Chapter 3.1 --- Compositing Projection in Direct Volume Rendering --- p.31Chapter 3.2 --- IsoRegion Leaping Acceleration --- p.34Chapter 3.2.1 --- IsoRegion Definition --- p.35Chapter 3.2.2 --- IsoRegion Construction --- p.37Chapter 3.2.3 --- IsoRegion Step Table --- p.38Chapter 3.2.4 --- Ray Traversal Scheme --- p.41Chapter 3.3 --- Experiment Result --- p.43Chapter 3.4 --- Improvement --- p.47Chapter 3.5 --- Chapter Summary --- p.48Chapter 4 --- Parallel Volume Rendering by Distributed Processing --- p.50Chapter 4.1 --- Multi-platform Loosely-coupled Parallel Environment Shell --- p.51Chapter 4.2 --- Distributed Rendering Pipeline (DRP) --- p.55Chapter 4.2.1 --- Network Architecture of a Loosely-Coupled System --- p.55Chapter 4.2.2 --- Data and Task Partitioning --- p.58Chapter 4.2.3 --- Communication Pattern and Analysis --- p.59Chapter 4.3 --- Load Balancing --- p.69Chapter 4.4 --- Heterogeneous Rendering --- p.72Chapter 4.5 --- Chapter Summary --- p.73Chapter 5 --- User Interface --- p.74Chapter 5.1 --- System Design --- p.75Chapter 5.2 --- 3D Pen Input Device --- p.76Chapter 5.3 --- Visualization Environment Integration --- p.77Chapter 5.4 --- User Interaction: Interactive Navigation --- p.78Chapter 5.4.1 --- Camera Model --- p.79Chapter 5.4.2 --- Zooming --- p.81Chapter 5.4.3 --- Image View --- p.82Chapter 5.4.4 --- User Control --- p.83Chapter 5.5 --- Chapter Summary --- p.87Chapter 6 --- Conclusion --- p.88Chapter 6.1 --- Final Summary --- p.88Chapter 6.2 --- Deficiency and Improvement --- p.89Chapter 6.3 --- Future Research Aspect --- p.91Appendix --- p.93Chapter A --- Common Error in Pre-multiplying Color and Opacity --- p.94Chapter B --- Binary Factorization of the Sample Composition Equation --- p.9

Doctor of Philosophy

dissertationWhile boundary representations, such as nonuniform rational B-spline (NURBS) surfaces, have traditionally well served the needs of the modeling community, they have not seen widespread adoption among the wider engineering discipline. There is a common perception that NURBS are slow to evaluate and complex to implement. Whereas computer-aided design commonly deals with surfaces, the engineering community must deal with materials that have thickness. Traditional visualization techniques have avoided NURBS, and there has been little cross-talk between the rich spline approximation community and the larger engineering field. Recently there has been a strong desire to marry the modeling and analysis phases of the iterative design cycle, be it in car design, turbulent flow simulation around an airfoil, or lighting design. Research has demonstrated that employing a single representation throughout the cycle has key advantages. Furthermore, novel manufacturing techniques employing heterogeneous materials require the introduction of volumetric modeling representations. There is little question that fields such as scientific visualization and mechanical engineering could benefit from the powerful approximation properties of splines. In this dissertation, we remove several hurdles to the application of NURBS to problems in engineering and demonstrate how their unique properties can be leveraged to solve problems of interest

Neural Radiance Fields: Past, Present, and Future

The various aspects like modeling and interpreting 3D environments and surroundings have enticed humans to progress their research in 3D Computer Vision, Computer Graphics, and Machine Learning. An attempt made by Mildenhall et al in their paper about NeRFs (Neural Radiance Fields) led to a boom in Computer Graphics, Robotics, Computer Vision, and the possible scope of High-Resolution Low Storage Augmented Reality and Virtual Reality-based 3D models have gained traction from res with more than 1000 preprints related to NeRFs published. This paper serves as a bridge for people starting to study these fields by building on the basics of Mathematics, Geometry, Computer Vision, and Computer Graphics to the difficulties encountered in Implicit Representations at the intersection of all these disciplines. This survey provides the history of rendering, Implicit Learning, and NeRFs, the progression of research on NeRFs, and the potential applications and implications of NeRFs in today's world. In doing so, this survey categorizes all the NeRF-related research in terms of the datasets used, objective functions, applications solved, and evaluation criteria for these applications.Comment: 413 pages, 9 figures, 277 citation

Training of Crisis Mappers and Map Production from Multi-sensor Data: Vernazza Case Study (Cinque Terre National Park, Italy)

This aim of paper is to presents the development of a multidisciplinary project carried out by the cooperation between Politecnico di Torino and ITHACA (Information Technology for Humanitarian Assistance, Cooperation and Action). The goal of the project was the training in geospatial data acquiring and processing for students attending Architecture and Engineering Courses, in order to start up a team of "volunteer mappers". Indeed, the project is aimed to document the environmental and built heritage subject to disaster; the purpose is to improve the capabilities of the actors involved in the activities connected in geospatial data collection, integration and sharing. The proposed area for testing the training activities is the Cinque Terre National Park, registered in the World Heritage List since 1997. The area was affected by flood on the 25th of October 2011. According to other international experiences, the group is expected to be active after emergencies in order to upgrade maps, using data acquired by typical geomatic methods and techniques such as terrestrial and aerial Lidar, close-range and aerial photogrammetry, topographic and GNSS instruments etc.; or by non conventional systems and instruments such us UAV, mobile mapping etc. The ultimate goal is to implement a WebGIS platform to share all the data collected with local authorities and the Civil Protectio

Computer aided intertrochanteric osteotomy planning and surgery simulation

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1994.Includes bibliographical references (p. 135-144).by Patrick J. Lord.Ph.D

Terrainosaurus: realistic terrain synthesis using genetic algorithms

Synthetically generated terrain models are useful across a broad range of applications, including computer generated art & animation, virtual reality and gaming, and architecture. Existing algorithms for terrain generation suffer from a number of problems, especially that of being limited in the types of terrain that they can produce and of being difficult for the user to control. Typical applications of synthetic terrain have several factors in common: first, they require the generation of large regions of believable (though not necessarily physically correct) terrain features; and second, while real-time performance is often needed when visualizing the terrain, this is generally not the case when generating the terrain. In this thesis, I present a new, design-by-example method for synthesizing terrain height fields. In this approach, the user designs the layout of the terrain by sketching out simple regions using a CAD-style interface, and specifies the desired terrain characteristics of each region by providing example height fields displaying these characteristics (these height fields will typically come from real-world GIS data sources). A height field matching the user's design is generated at several levels of detail, using a genetic algorithm to blend together chunks of elevation data from the example height fields in a visually plausible manner. This method has the advantage of producing an unlimited diversity of reasonably realistic results, while requiring relatively little user effort and expertise. The guided randomization inherent in the genetic algorithm allows the algorithm to come up with novel arrangements of features, while still approximating user-specified constraints

Earth Observation Open Science and Innovation

geospatial analytics; social observatory; big earth data; open data; citizen science; open innovation; earth system science; crowdsourced geospatial data; citizen science; science in society; data scienc