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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.
251

Content-based video indexing for sports applications using integrated multi-modal approach.

Tjondronegoro, Dian W, mikewood@deakin.edu.au January 2005 (has links)
This thesis presents a research work based on an integrated multi-modal approach for sports video indexing and retrieval. By combining specific features extractable from multiple (audio-visual) modalities, generic structure and specific events can be detected and classified. During browsing and retrieval, users will benefit from the integration of high-level semantic and some descriptive mid-level features such as whistle and close-up view of player(s). The main objective is to contribute to the three major components of sports video indexing systems. The first component is a set of powerful techniques to extract audio-visual features and semantic contents automatically. The main purposes are to reduce manual annotations and to summarize the lengthy contents into a compact, meaningful and more enjoyable presentation. The second component is an expressive and flexible indexing technique that supports gradual index construction. Indexing scheme is essential to determine the methods by which users can access a video database. The third and last component is a query language that can generate dynamic video summaries for smart browsing and support user-oriented retrievals.
252

Time and modality in Vietnamese : a contrastive study of Vietnamese and English

Ha, Nguyen Hong, n/a January 1985 (has links)
The present study is an attempt to give a description of how temporal and modal meanings are expressed in Vietnamese, and to relate the description to English by way of translation correspondence. The study is, therefore, a contrastive work on Time and Modality in Vietnamese and English. It is hoped that Vietnamese students might find in this work some kind of help that may facilitate their study of English grammar as regards time and mood. In chapter 1, the author presents a brief history of foreign language teaching in Vietnam, and the role of English as a foreign language in the country at present. He also discusses problems confronting Vietnamese teachers and students in teaching and learning English and states the aims of the study. Next, the structure of the Vietnamese verb-phrase is discussed, with a view to giving the reader some idea of how auxiliaries operate in Vietnamese. In chapter 2, a description of temporal expression in Vietnamese is presented, with emphasis on the uses of the so-called "time auxiliaries". Also, time adverbs, time clauses and questions with time in Vietnamese are discussed. Chapter 3 deals with modal expression in Vietnamese. In this chapter special attention is given to the uses of the modal auxiliaries. Attempts are then made to describe the so-called "attitudinal disjuncts" and conditional sentences in Vietnamese. In chapter 4, implications for teaching time and modality in English to Vietnamese students are given. The author suggests some teaching points, which, through the present contrastive work, are likely to be some of the most difficult areas for Vietnamese speakers and therefore should be given the most particular attention.
253

A System for Driver Identity Verification

Hagemann, Andreas, Björk, Hanna January 2005 (has links)
<p>Different security issues are a top subject around the world, especially since the terror threats seem to intensify. In the same time, the transport industry suffer from problems with smuggling and theft of valuable goods. One way to increase the security might be to have a verification system installed in commercial trucks, in order to assure that the driver is the proper one.</p><p>This thesis has two purposes. One is to find appropriate methods for driver verification and build a prototype of a verification system which can be used for testing and further development. The other is to study how truck drivers perceive such a system and how their conception goes along with the growing demand for higher security. The present work is the result of a cooperation between an engineer and a cognitive scientist. The thesis focuses on the transport industry and was performed for Volvo Technology Corporation (VTEC), Gothenburg, Sweden.</p><p>Eleven available verification methods were studied. To enable a well-based selection of methods to implement in the prototype, inquiries and interviews with truck drivers and haulage contractors were carried out to complement the theoretical study. </p><p>One regular and three biometric verification methods were chosen for the test; fingerprint verification, face recognition, voice recognition and PIN verification. These methods were put together to a prototype system that was implemented in a truck simulator. A graphical user interface was developed in order to make the system user friendly. The prototype system was tested by 18 truck drivers. They were thoroughly interviewed before and after the test in order to retrieve their background, expectations and opinions as well as their perceptions and experiences of the test. </p><p>Most of the test participants were positive to the prototype system. Even though they did not feel a need for it today they believed it to “be the future”. However, some participants felt uncomfortable with the system since they felt controlled by it. It became clear how important it is to have a system that respect the users’ privacy and to assure that the users are well informed about how the system is used. Some of the technology used for the verification system requires more development to fit in the automotive context, but it is considered to be possible to achieve a secure and robust system.</p>
254

From Conceivability to Possibility : An Essay in Modal Epistemology / Från tänkbarhet till möjlighet : En studie i modal kunskapsteori

Berglund, Anders January 2005 (has links)
<p>This study deals with the thesis that conceivability implies possibility. Confronted with alleged counterexamples to this thesis, some philosophers have turned to what may be called “idealized” or “more demanding” notions of conceivability. I argue that in turning to such notions, they have made the thesis useless to limited beings like us for attaining modal knowledge. However, in refusing to identify conceivability with demanding or idealized notions, we cannot maintain that conceivability always implies possibility. Essentially, there are two ways to proceed: to view conceivability as a mere guide to possibility, or to argue that the conceivability thesis is a local truth, i.e., a truth with respect to a certain class of statements. I defend the latter alternative. This class of statements employs concepts with respect to which doubt concerning the conceivability thesis is to be regarded as general skepticism, not as skepticism relating to the conceivability thesis itself.</p><p>I proceed by outlining an interpretation of strict possibility—i.e., the kind of possibility that I take the conceivability thesis to be about—according to which modal truths depend essentially on conceptual relations, as opposed to obtaining purely in virtue of properties of things themselves. Given this account, on which both ideal conceivability and strict possibility have a conceptual ground, I argue that these notions are not only coextensional but relate to one and the same property of statements. I further argue that the impossible is unimaginable, but that it is conceivable in the sense that one can misdescribe the contents of imagination.</p>
255

Multi-modal registration of maxillodental CBCT and photogrammetry data over time

Bolandzadeh-Fasaie, Niousha 06 1900 (has links)
This thesis aims at introducing a methodology for clinical evaluation of orthodontic treatments using three-dimensional dento-maxillofacial images. Since complementary information is achieved by integrating multiple modalities, cone-beam computed tomography (CBCT) and stereophotogrammetry technologies are used to develop a methodology for tracking bone and facial skin variations over time. Our proposed methodology consists of a two-phase registration procedure. In the first phase, the multimodal images are registered using an extrinsic landmark-based registration followed by a robust Iterative Closest Points (ICP) method. In the second phase, by utilizing specific anatomical landmarks, single modal images of the skull and the mandible are registered over time using an intrinsic landmark-based registration method followed by the robust ICP algorithm. The results of registrations show that the signed error distribution of both mandible and skull registrations follow a normal distribution while all the errors fall within the CBCT precision range.
256

Sound Transmission Through A Fluctuating Ocean: A Modal Approach

Udovydchenkov, Ilya A. 21 December 2007 (has links)
Sound transmission through a fluctuating deep ocean environment is considered. It is assumed that the environment consists of a range-independent background, on which a small-scale perturbation, due for example to internal waves, is superimposed. The modal description of underwater sound propagation is used extensively. The temporal spread of modal group arrivals in weakly range-dependent deep ocean environments is considered. The phrase "modal group arrival" refers to the contribution to a transient wavefield corresponding to a fixed mode number. It is shown that there are three contributions to modal group time spreads which combine approximately in quadrature. These are the reciprocal bandwidth, a deterministic dispersive contribution, and a scattering-induced contribution. The latter two contributions are shown to be proportional to the waveguide invariant beta, a property of the background sound speed profile. The results presented are based mostly on asymptotic theory. Some extensions of the asymptotic modal theory are developed. These theoretical results are shown to agree well with full-wave numerical wavefield simulations and available exact mode theoretical results. Theoretical predictions of modal group time spreads are compared to estimates derived from data that was collected during the 2004 LOAPEX experiment. The effects of deficiencies in the receiving array on estimates of modal group time spreads are discussed. It is shown that in spite of array deficiencies in the LOAPEX measurements it is possible to estimate modal group time spreads for almost all propagating modes and these estimates agree well with results obtained from numerical simulations and the developed theory. The effect of ocean internal waves on sound speed fluctuations is also considered, motivated by the observation that the amount of energy being scattered along the propagation path is sometimes greater in the experimental data than predicted by numerical simulations and theory. It is shown that the usual assumption that the potential sound speed gradient is proportional to the squared buoyancy frequency is often not a good approximation.
257

Human Identification Based on Three-Dimensional Ear and Face Models

Cadavid, Steven 05 May 2011 (has links)
We propose three biometric systems for performing 1) Multi-modal Three-Dimensional (3D) ear + Two-Dimensional (2D) face recognition, 2) 3D face recognition, and 3) hybrid 3D ear recognition combining local and holistic features. For the 3D ear component of the multi-modal system, uncalibrated video sequences are utilized to recover the 3D ear structure of each subject within a database. For a given subject, a series of frames is extracted from a video sequence and the Region-of-Interest (ROI) in each frame is independently reconstructed in 3D using Shape from Shading (SFS). A fidelity measure is then employed to determine the model that most accurately represents the 3D structure of the subject’s ear. Shape matching between a probe and gallery ear model is performed using the Iterative Closest Point (ICP) algorithm. For the 2D face component, a set of facial landmarks is extracted from frontal facial images using the Active Shape Model (ASM) technique. Then, the responses of the facial images to a series of Gabor filters at the locations of the facial landmarks are calculated. The Gabor features are stored in the database as the face model for recognition. Match-score level fusion is employed to combine the match scores obtained from both the ear and face modalities. The aim of the proposed system is to demonstrate the superior performance that can be achieved by combining the 3D ear and 2D face modalities over either modality employed independently. For the 3D face recognition system, we employ an Adaboost algorithm to builda classifier based on geodesic distance features. Firstly, a generic face model is finely conformed to each face model contained within a 3D face dataset. Secondly, the geodesic distance between anatomical point pairs are computed across each conformed generic model using the Fast Marching Method. The Adaboost algorithm then generates a strong classifier based on a collection of geodesic distances that are most discriminative for face recognition. The identification and verification performances of three Adaboost algorithms, namely, the original Adaboost algorithm proposed by Freund and Schapire, and two variants – the Gentle and Modest Adaboost algorithms – are compared. For the hybrid 3D ear recognition system, we propose a method to combine local and holistic ear surface features in a computationally efficient manner. The system is comprised of four primary components, namely, 1) ear image segmentation, 2) local feature extraction and matching, 3) holistic feature extraction and matching, and 4) a fusion framework combining local and holistic features at the match score level. For the segmentation component, we employ our method proposed in [111], to localize a rectangular region containing the ear. For the local feature extraction and representation component, we extend the Histogram of Categorized Shapes (HCS) feature descriptor, proposed in [111], to an object-centered 3D shape descriptor, termed Surface Patch Histogram of Indexed Shapes (SPHIS), for surface patch representation and matching. For the holistic matching component, we introduce a voxelization scheme for holistic ear representation from which an efficient, element-wise comparison of gallery-probe model pairs can be made. The match scores obtained from both the local and holistic matching components are fused to generate the final match scores. Experimental results conducted on the University of Notre Dame (UND) collection J2 dataset demonstrate that theproposed approach outperforms state-of-the-art 3D ear biometric systems in both accuracy and efficiency.
258

From Conceivability to Possibility : An Essay in Modal Epistemology / Från tänkbarhet till möjlighet : En studie i modal kunskapsteori

Berglund, Anders January 2005 (has links)
This study deals with the thesis that conceivability implies possibility. Confronted with alleged counterexamples to this thesis, some philosophers have turned to what may be called “idealized” or “more demanding” notions of conceivability. I argue that in turning to such notions, they have made the thesis useless to limited beings like us for attaining modal knowledge. However, in refusing to identify conceivability with demanding or idealized notions, we cannot maintain that conceivability always implies possibility. Essentially, there are two ways to proceed: to view conceivability as a mere guide to possibility, or to argue that the conceivability thesis is a local truth, i.e., a truth with respect to a certain class of statements. I defend the latter alternative. This class of statements employs concepts with respect to which doubt concerning the conceivability thesis is to be regarded as general skepticism, not as skepticism relating to the conceivability thesis itself. I proceed by outlining an interpretation of strict possibility—i.e., the kind of possibility that I take the conceivability thesis to be about—according to which modal truths depend essentially on conceptual relations, as opposed to obtaining purely in virtue of properties of things themselves. Given this account, on which both ideal conceivability and strict possibility have a conceptual ground, I argue that these notions are not only coextensional but relate to one and the same property of statements. I further argue that the impossible is unimaginable, but that it is conceivable in the sense that one can misdescribe the contents of imagination.
259

Evaluating bicycle accessibility and bike-bus integration infrastructure : Saskatoon, SK, 2006

MacIntyre, Stephen Joseph 15 January 2007
The study proposes an application of Talens (2003) methodological framework for assessing neighbourhood-level (i.e., non-motorised mode) accessibility, and offers recommendations for improving non-motorized transportation (NMT) accessibility to enhance multimodal integration between bicycles and buses in contemporary North American suburban neighbourhoods. Accessibility (or access) is defined as the average travel time or distance between a given origin and destination along the shortest available street network route. The study considers characteristics of the transportation network such as available route directness, facilities, and transit service provision to determine their impacts on bicycle access. A further methodology for comparing bicycle versus bus modal efficiencies within suburban contexts is developed and applied to the case study. A review of approaches designed to promote bicycling while discouraging personal automobile use provides a toolbox of proven treatments that are applied to a case study of Saskatoon, Saskatchewan a city of approximately 200,000 people. The approach provides a process that can be used by city or transit planners to identify neighbourhoods that lack sufficient access and apply treatments that improve bicycle accessibility and bicycle-transit integration. Results suggest existing potential for the bicycle as an access mode within contemporary suburban neighbourhood transportation networks. The case study supports the notion that suburban bicycle-bus integration could be used as a viable alternative to automobiles for daily home-to-node activity trips, and raises questions about the current allocation of public transit service to suburban routes within the context of the case study. Discussion and conclusions suggest directions for future research in this field of sustainable urban transportation planning.
260

Autopsy: Redesigning Urban Transportation

Perkins, Gregory McKay 23 August 2010 (has links)
According to the United Nations’ report, State of World Population 2008, humankind has come to a turning point; more than 50% of the earth’s population now lives in urban centres. Along with considerations for housing, employment, and public health, this shift changes the way we design roads and streets; it escalates the number of automobiles in urban areas with finite room for road expansion. Space constraints, along with intense development of alternative transportation fuels, and the burden of sprawling suburbs on municipal infrastructures suggest the hypothesis that before we run out of energy alternatives for personal mechanized transport, we will run out of space in which to use it. This thesis explores how Toronto, a city largely designed for automobile use, is being re-adapted into a city wherein public and active transportation can once again be the primary means of urban mobility and the opportunities inherent in the development of interregional multi-modal transit stations for the cultivation of civic space, local commerce, urban form, and commercial transportation.

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