高莘. / 論文(哲學博士)--香港中文大學, 2007. / 參考文獻(p. 229-254). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in Chinese and English. / Lun wen (zhe xue bo shi)--Xianggang Zhong wen da xue, 2007. / Can kao wen xian (p. 229-254). / Gao Xin.

In Chapter 2, the ways how Abe interprets the Buddhist idea of sunyata for his western audience are explored. There are three characteristics in his interpretation, namely clarifying the meaning of sunyata in comparison with the western philosophical and religious concepts, emphasizing the subjective aspect of sunyata, and taking sunyata as a dynamic activity rather than a static state. Among these characteristics, the dynamic interpretation of sunyata is of the most importance. Abe's interpretation goes beyond the classical meaning of sunyata formulated by Nagarjuna, and distinguishes itself from the traditional Chinese Buddhist thought. This dynamic interpretation of sunyata is arguably an original interpretation made by Abe and might have been inspired by the western thought he dialogued with. / In Chapter 3, this thesis scrutinizes closely Abe's proposal of "kenotic God" and summarizes the Christian responses attracted. According to Abe, the kenosis of Christ involves the kenotic understanding of God, which means the original nature of God is self-emptying. Abe was not satisfied with the traditional Christian doctrine of Trinity, and proposed "Great zero" or "Absolute nothingness" as the ground of the divine Trinity. Except very few Christian theologians who totally agree or disagree to Abe's idea, most of them accept his idea of "kenotic God", but refuse to take "Absolute nothingness" instead of Trinity as the ultimate divine reality. It can be said that Abe's proposal of "kenotic God" aims at offering a Buddhist interpretation, which is based on the experience of sunyata, as an aid to help Christians to deepen their understanding of God. Although his idea is not completely accepted by most of the Christian theologians, it exercises some sort of transformative influence. Many Christian theologians admitted that their understandings of God had been significantly changed by Abe. / In chapter 4, the present study examines if the ideal of "mutual transformation" is fulfilled in Abe's endeavour in Buddhist-Christian dialogue. As demonstrated in Chapter 3, Abe's proposal of "kenotic God" aims at deepening the Christian understanding of the divine ultimate reality from a Buddhist perspective. And it does have some transformative effects among some Christian theologians, in this regard, one side of the "mutual transformation" is realized. The remaining side to be explored is if Abe's understanding of Buddhism has also been transformed by the Christian insight. On the social-historical level, Abe points out that Buddhism should learn from Christianity, especially its view of justice. Abe also attempted to develop the Buddhist social ethics and a Buddhist view of history through encountering Christian theologians. However, on the ultimate level, as Cobb criticizes, Abe shows a strong self-confidence in the Buddhist understanding of ultimate reality and an equally strong resistance to change. Nevertheless, through a comparative study of his interpretation of sunyata and process thought, it is found that Abe's understanding of ultimate reality, namely "Dynamic sunyata", might have probably been inspired by the dynamic structure of process thought together with its idea about the bipolar nature of God. It therefore can be concluded that Abe's understanding of Buddhism has also been transformed in a fundamental way by Christian thought. (Abstract shortened by UMI.) / Masao Abe was probably the most prominent and active Buddhist scholar in Buddhist-Christian Dialogue in the last few decades. / This thesis consists of five major parts: In Chapter 1, Abe's theory about interfaith dialogue, which includes the necessity of dialogue, the methodological issues, its final goal, and how to understand the plurality and unity of world religions, will be discussed. According to Abe, nowadays the validity of religion in general is seriously challenged by anti-religious ideologies, especially scientism and nihilism. To cope with this challenge, interfaith dialogue must go beyond mutual understanding, and engage in mutually creative transformation. For him interfaith dialogue should involve two steps: first, clarify one's own religious idea, and make ideas from different traditions encounter with each other; second, liberate oneself from one's traditional framework of doctrine and practice and learn from each other in order to realize mutually creative transformation. Only in a transformative dialogue, can religions demonstrate their deepest authentic spirituality and overcome the anti-religious ideologies. In respect of religious pluralism, Abe proposed to take the Buddhist three-body doctrine as a working hypothesis to establish the dynamic unity of world religions. Through comparing Abe's proposal with that of John Hick and John B. Cobb, Jr. respectively, this thesis argues that although Abe's proposal is more capable of explaining the plurality and unity of world regions as well as giving a theoretical support for mutual learning, the proposal also implies a kind of Buddhist superiority, which may prevent Buddhists from learning from other religions at the ultimate or inner most level. / 李宜靜. / 論文(哲學博士)--香港中文大學, 2007. / 參考文獻(p. 195-212). / Adviser: Pan-Chiu Lai. / Source: Dissertation Abstracts International, Volume: 69-02, Section: A, page: 0639. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in Chinese and English. / School code: 1307. / Lun wen (zhe xue bo shi)--Xianggang Zhong wen da xue, 2007. / Can kao wen xian (p. 195-212). / Li Yijing.

A simple bottom-up-based synthetic strategy named a solvothermal technique is introduced as the primary synthetic approach and its crystal growth mechanism is scrutinized. N-type cobalt-doped ZnO-based DMS nanocrystals are employed as a model system, and characterized by a broad spectrum of advanced microscopic and spectroscopic techniques. It is found that the self-orientation growth mechanism, imperfect oriented attachment, is intimately correlated with the high-temperature ferromagnetism via defects. The influence of processing on the magnetic properties, such as compositional variations, reaction conditions, and post-growth treatment, is also studied. In this way, an in-depth understanding of processing-structure-property interrelationships and origins of magnetism in DMS nanocrystals are obtained in light of the theoretical framework of a spin-split impurity band model. In addition, a nanoscale spinodal decomposition phase model is also briefly discussed. / Following the similar synthetic route, copper- and manganese-doped ZnO nanocrystals have been synthesized and characterized. They both show high-temperature ferromagnetism in line with the aforementioned theoretical model(s). Moreover, they display interesting exchange biasing phenomena at low temperatures, revealing the complexity of magnetic phases therein. / Spintronics (spin transport electr onics), in which both spin and charge of carriers are utilized for information processing, is believed to challenge the current microelectronics and to become the next-generation electronics. Nanostructured spintronic materials and their synthetic methodologies are of paramount importance for manufacturing future nanoscale spintronic devices. This thesis aims at studying synthesis, characterization, and magnetism of transition-metal-doped zinc oxide (ZnO) nanocrystals---a diluted magnetic semiconductor (DMS)---for potential applications in future nano-spintronics. / The crystal growth strategy demonstrated in this work not only provides a more convenient approach to directly tailor magnetic properties of advanced multifunctional spintronic materials on a nanometer scale but also contributes to a deeper insight into the microscopic origin of magnetism in wide-band-gap oxide DMSs. / Wang, Xuefeng. / "August 2007." / Adviser: J. B. Xu. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1230. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

Finally, we also propose and demonstrate an integrated Mach-Zehnder optical diplexer (IMZOD) for possible use in an integrated silicon optical amplifier. The diplexer is based on two rnultimode interferometers (MMIs) and a Mach-Zehnder interferometer (MZI), and has potential use in an integrated silicon waveguide optical amplifier, to combine or separate the pump signal (1440nm) and probe signal (1556nm) for monolithic implementation of a silicon Raman amplifier. / Helium ion implantation can not only reduce the free-carrier loss, but can also enhance the detection responsivity of below-bandgap wavelengths (1440 1590 nm). We propose and demonstrate an in-line channel power monitor (ICPM) based on helium ion implanted silicon waveguides. The implanted waveguide can detect light at 1440 1590 nm which are normally not detectable by silicon. We study the enhanced photoresponse of helium ion implanted waveguide samples which were annealed at different temperatures and for different durations. / Recently there has been much interest in silicon optical amplifiers and lasers relying on stimulated Raman scattering (SRS), which, despite the much shorter waveguide lengths possible in silicon compared with silica optical fiber, can still provide large optical gain because of the large Raman coefficient of silicon and small mode field areas. However, two-photon absorption (TPA) generated free-carrier absorption (FCA) loss can exceed the Raman gain. In this thesis, experiments and theoretical model will he discussed and analyzed, showing that helium ion implantation can successfully reduce the optical losses due to free-carriers and allow net gain to be attained by continuous-wave (CW)-pumped SRS without requiring external bias to remove the photo-generated free carriers. The theoretical study of dynamics of free carrier lifetime of the silicon waveguides will be described. The effective nonlinear length of the silicon waveguides is defined and studied. The theoretical and experimental studies of the enhanced spectral broaden induced by self-phase-modulation (SPM) are carried out in helium on implanted silicon waveguides. / Silicon-on-insulator (SOI) wafers are an attractive platform for the fabrication of planar lightwave circuits (PLCs) because they offer the potential for low-cost fabrication using mature complementary metal--organic--semiconductor (CMOS) compatible processes developed in the microelectronics industry. At the wavelengths of interest for telecommunications, SOI waveguides can have low optical losses (0.1dB/cm). Besides, the strong optical confinement offered by the high index contrast between silicon (Si) (n=3.45) and silicon dioxide (SiO2) (n=1.45) makes it possible to scale photonic devices to sub-micron level. In addition, the high optical intensity arising from the strong optical confinement inside the waveguide makes it possible to observe nonlinear optical effects, such as Raman and Kerr effects, in chip-scale devices. / We then make use of the ICPM to perform a system application, called optical-burst-and-transient-equalizer (OBTE). The OBTE may provide a compact and low-cost solution to compensate gain-transient, gain-spectrum-tilt and to equalize the upstream packet amplitude in erbium doped fiber amplifier (EDFA) amplified hybrid dense-wavelength-division-multiplexed (DWDM) and time-division-multiplexed (TDM) passive-optical-networks (PONs). The OBTE may be monolithically integrated on SOI platform and is potentially low cost and compact. The OBTE can compensate complicated gain slope shape, which may be generated in cascaded EDFAs or deliberate channel add/drop, based on individual channel equalization. 15-dB receiver sensitivity improvement at 10 Gbit/s bit-error-rate (BER) measurements of 10-9 was achieved by the compensation. / Liu, Yang. / "August 2007." / Adviser: Hon Ki Tsang. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1212. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

Optical signal processing plays a key role in a high capacity all-optical communication network. Rapid advances in the processing technology offers new solutions to enhance fiber communications. This thesis focuses on the development of new components and techniques for optical signal processing. / The application of optical nonlinearities in fibers and in semiconductor devices is of great importance in different fields of research. In this thesis, we report our findings in the development of new techniques for photonic signal processing. Two different approaches for extinction ratio enhancement of an amplitude-shift keying (ASK) signal have been demonstrated using self-phase modulation in a highly nonlinear bismuth oxide fiber. The differential phase-shift keying (DPSK) modulation format is also receiving much attention owing to its improved receiver sensitivity and its higher tolerance to signal degradation by undesired fiber nonlinearities. We demonstrated all-optical processing of DPSK signals using different nonlinear phenomena in a semiconductor optical amplifiers, a dispersion-flattened highly nonlinear photonic crystal fiber, and a highly nonlinear bismuth oxide fiber. Various application areas including extinction ratio enhancement, amplitude noise reduction, phase noise reduction, wavelength conversion and wavelength multicasting have been realized using four-wave mixing, self-phase modulation, and cross-phase modulation in the optical elements. (Abstract shortened by UMI.) / The birefringent comb filter is an important element in the processing of microwave and optical signals. To increase the flexibility in its operation, it is desirable for the filter to be tunable in both the spectral position and the spacing of the comb. By incorporating an electro-optic phase modulator to control the overall birefringence, the output comb can be rapidly modulated in the spectral domain. We also introduced a new architecture of a dual-pass Lyot filter that offers the highest tunability of the comb spacing at a given number of birefringent fiber elements. Selectivity of the spacing is based on different alignments between the fiber axes in our cascadable scheme. We applied the birefringent comb filter to multi-wavelength laser source generation using either a semiconductor or a fiber-based gain element. By electrical tuning of the birefringence inside a semiconductor optical amplifier ring laser, a waveband switchable multi-wavelength source has been obtained. In an erbium-doped fiber (EDF) laser, multi-wavelength lasing is inhibited at room temperature owing to the homogeneously broadened gain medium. To address this problem, two different types of fiber nonlinearities, stimulated Brillouin scattering and four-wave mixing, are incorporated separately to the EDF laser to provide self-stabilization of the multi-wavelength oscillation. In addition to multi-wavelength source generation, we further applied the birefringent comb filter to multiply the repetition rate of a high-speed pulsed source using the spectral elimination approach. Repetition rate multiplication from 10 to 40 GHz has been simultaneously achieved for four ITU-grid laser sources around 1550 nm, resulting in an aggregate pulse rate of 160 GHz. The phase coherence of the output pulses is also preserved. / Fok, Mei Po Mable. / "August 2007." / Adviser: Chester Shu. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1198. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

For the first method, a novel linearization scheme for CMOS double-balanced mixer based on the use of multi-bias dual-gate transistors is presented. In this technique, two intermodulation distortion components with proper phase relationship, generated by devices operating at different bias conditions, are added together to cancel each other for the improvement of mixer's linearity. The measured performance of a fabricated CMOS mixer operating at RF frequency of 2.45GHz and LO frequency of 2.35GHz is demonstrated. Over 35dB of IMD reduction is achieved by the proposed method under optimal biasing condition. / In the second design, a novel linearization scheme for cascode amplifier based upon capacitive feedback is presented. This method involves the optimal design of the feedback network for IMD reduction. By using Volterra series analysis, expression for IMD products is derived and the corresponding circuit parameters for optimized linearity are obtained. For experimental verification, CMOS cascode amplifiers are designed and fabricated to operate at 2.45GHz with supply voltage of 2V. By measurement, IIP3 is improved of almost 7dB by using the proposed feedback technique. The performance dependency of the fabricated amplifiers under different bias conditions is also examined. The results indicate that the proposed technique can offer low sensitivity to the variation of process parameters. / Linearity is one of the major requirements in modern communication systems due to the limited channel spacing. In the past years, various linearization schemes have been studied extensively for RF circuit design such as low-noise amplifiers and power amplifiers. These techniques offer IMD reduction at the expense of circuit complexity. In the last decade, much effort has been devoted to the development of single-chip RF transceiver using sub-micron CMOS technology. This thesis presents three simple and effective linearization techniques for CMOS mixer and amplifier design. They are experimentally verified by circuit fabrication based on 0.35mum CMOS process. / The last approach combines the advantages of source degeneration and the capacitive feedback for cascode amplifier linearization. Experiments are performed on CMOS amplifiers operating at 2.45GHz, and more than 11dB of IIP3 enhancement is observed. / Au Yeung, Chung Fai. / "August 2007." / Adviser: Chang Kwok Keung. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1189. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 153-161). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

Another objective of this work is to study the perceptual optimized video object coding. Since MPEG-4 treats a scene as a composition of video objects that are separately encoded and decoded, such a flexible video coding framework makes it possible to code different video objects with different priorities. It is necessary to analyze the priorities of video objects according to their intrinsic properties and psycho-visual characteristics such that the bit budget can be distributed properly to video objects to improve the perceptual quality of the compressed video. An object-level visual attention model is developed to automatically obtain the visual attention information of video objects. The visual attention values of video objects are calculated and incorporated in the newly developed dynamic bit allocation mechanism to improve the objective quality of the high priority objects such that the perceptual quality of the overall picture can be maximized. / As strict rate control algorithms used in video coding sacrifice the quality consistency, the rate distortion tradeoff is important to achieve a balance between the bit rate and quality. A novel separable rate distortion modeling method is proposed to analyze the rate distortion characteristics of the color video signal. This method provides higher estimation accuracy when compared to the non-separable modeling method. To achieve rate distortion tradeoff in H.264/AVC, a new control strategy is presented. The feedback from the encoder buffer is analyzed by a control-theoretic adaptation approach to avoid buffer overflow and underflow. A novel rate distortion tradeoff controller is designed by considering both the quality variation and buffer fluctuation. Smooth video quality is achieved and the relevant constraints are satisfied. / Due to the unique features of the video object coding such as both texture and shape introducing distortions and video objects being of arbitrarily shapes, the rate distortion analysis and optimization strategies are different from the traditional rectangular frame-based techniques. Two new rate distortion modeling methods are proposed for the shape coding. The first one is a linear rate distortion modeling method. The computational complexity is low and the estimation is accurate. To further improve the modeling performance, a novel statistical learning based method is proposed by incorporating shape features to provide rate distortion analysis for the shape coding. Therefore, a joint texture-shape rate distortion modeling approach is derived by integrating the texture and shape rate distortion models. The new joint texture-shape distortion models provide the basis for optimal bit allocation for the video object coding to minimize the coding distortion with the bit rate constraint and stabilize the buffer fullness. The major contribution of this optimal bit allocation scheme is to provide a unified solution for the following two problems: how to allocate bits between the texture and shape and how to distribute the hit budget for multiple video objects, simultaneously. / This thesis addresses rate distortion analysis, optimization, and control problems in video coding. These rate distortion issues not only provide the theoretical background but also are concerned with the practical design for video coding systems. The main objective of this thesis is to consider the problems associated with analyzing the rate distortion characteristics of the video source and providing optimal solutions or tradeoffs for the rate and distortion in video coding systems. More specifically this thesis focuses on both the object-based video coding system, MPEG-4, and the rectangular frame-based video coding system, H.264/AVC. / Chen, Zhenzhong. / "July 2007." / Adviser: King Ngi Ngan. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1194. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 225-247). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

Previous perspective reparameterizations approximate the aliasing errors for the points in a 2D space---the points along the view direction (i.e. horizontal plane in view space), from a geometric intuition. There's no explicit way to qualitatively analyze the aliasing elsewhere. We thus derive the global representation of aliasing functions based on the solid mathematical analysis. Using the global representation, we propose the Direction-adaptive Perspective Shadow Maps (DirPSMs) to offer enhanced shadow rendering in real-time applications. / Shadows are essential for the realism of computer-generated images, which dramatically enhance our perception of virtual scenes by providing useful visual hints. Even tremendous advances in graphics rendering algorithms and programmable GPUs have made real-time and photo-realistic rendering a reality, the synthesis of realistic shadowing effects is still challenging and computationally intensive. Shadow mapping is one of the most popular algorithms for real-time shadow rendering, which has been extensively adopted in real-time applications by its generality and efficiency. However, shadow mapping suffers from the inherent aliasing problems such as jagged shadow boundaries and incorrect self-shadowing due to the image-based nature. In this thesis, we present several shadow rendering techniques to render anti-aliased shadows via shadow mapping especially for large-scale and dynamic scenes. / The Parallel-Split Shadow Maps (PSSMs) scheme is first proposed for realistic and real-time shadow rendering towards next generation of three-dimensional computer games. This scheme splits the view frustum into multiple parts using clip planes parallel to the view plane, and then generates multiple smaller shadow maps for the split parts. A fast and robust split strategy based on the analysis of shadow map aliasing is developed, to produce a moderate aliasing distribution over the whole depth range. Hardware-specific accelerations are also implemented and tested to remove the extra rendering passes caused by using multiple shadow maps. / These techniques are intuitive to implement without using complex data structures. They are designed to improve both quality and performance of shadow rendering in large-scale and dynamic scenes. / With the observation that the sampling density at the light in the post-perspective space better accommodates the requirements for the reconstruction of shadowed images, perspective reparameterization techniques warp shadow maps using the perspective transform to reduce aliasing errors for the objects near the viewer. One limitation in this line of research is that the approximated representation of aliasing errors is only valid for the ideal case in which the light and view directions are orthogonal. We thus establish the generalized perspective reparameterization functions to adaptively adjust the warping strength as the light and/or viewer moves. With the direction-dependent representations of aliasing errors, we subsequently develop three enhanced perspective reparameterizations to better handle general cases, including Generalized Linear Perspective Reparameterization (GLPR), Generalized Minimum-Norm Perspective Reparameterization (GMNPR) and Focus-preserving Trapezoidal Shadow Maps (FTSMs). / Zhang, Fan. / "August 2007." / Adviser: Hanqiu Sun. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1126. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 147-155). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

Acquiring 3-D motion of a camera from image sequences is one of the key components in a wide range of applications such as human computer interaction. Given the 3-D structure, the problem of camera motion recovery can he solved using the model-based approaches, which are well-known and have good performance under a controlled environment. If prior information on the scene is not available, traditional Structure from Motion (SFM) algorithms, which simultaneously estimate the scene structure and pose information, are required. The research presented in this thesis belongs to a different category: Motion from Motion (MFM), in which the main concern is the camera position and orientation. To be more precise, MFM algorithms have the capability of estimating 3-D camera motion directly from 2-D image motion without the explicit reconstruction of the scene structure, even though the 3-D model structure is not known in prior. As keeping track of the structural information is no longer required, putting these types of algorithms into real applications is relatively easy and convenient. / It is demonstrated in the experiments that the proposed algorithms are efficient, stable and accurate compared to several existing approaches. Furthermore, they have been put into applications such as mixed reality, virtual reality, robotics and super-resolution to show their performance in real situations. / The objective of this thesis is to develop a high-speed recursive approach that tackles the MFM problem. On the way to the final goal, a series of methods, each having its own strengths and characteristics, have been studied. (1) The first algorithm computes the camera pose from a monocular image sequence. The trifocal tensor is incorporated into the Extended Kalman Filter (EKF) formulation. The step of computing the 3-D models can thus be eliminated. (2) The proposed approach is then extended to the recovery of motion from a stereo image sequence. By applying the trifocal tensor to a stereo vision framework, the trifocal constraint becomes more robust and is not likely to be degenerate. In addition, the twist motion model is adopted to parameterize the 3-D motion. It does not suffer from singularities as Euler angles, and is minimal as opposed to quaternion and the direct use of rotation matrix. (3) The third method introduces the Interacting Multiple Model Probabilistic Data Association Filter (IMMPDAF) to the MFM problem. The Interacting Multiple Model (IMM) technique allows the existence of more than one dynamic system and in return leads to improved accuracy and stability even under abrupt motion changes. The Probabilistic Data Association (PDA) framework makes the automatic selection of measurement sets possible, resulting in enhanced robustness to occlusions and moving objects. As the PDA associates stereo correspondences probabilistically, the explicit establishment of stereo matches is not necessary except during initialization, and the point features present in the outer region of the stereo images can be utilized. / Yu, Ying Kin. / "July 2007." / Adviser: Wong Kin Hong. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1125. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 120-130). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

In summary, the viewpoint of random graphs indeed provides us an opportunity of improving some existing machine learning algorithms. / In this thesis, we establish three machine learning models on random graphs: Heat Diffusion Models on Random Graphs, Predictive Random Graph Ranking, and Random Graph Dependency. The heat diffusion models on random graphs lead to Graph-based Heat Diffusion Classifiers (G-HDC) and a novel ranking algorithm on Web pages called DiffusionRank. For G-HDC, a random graph is constructed on data points. The generated random graph can be considered as the representation of the underlying geometry, and the heat diffusion model on them can be considered as the approximation to the way that heat flows on a geometric structure. Experiments show that G-HDC can achieve better performance in accuracy in some benchmark datasets. For DiffusionRank, theoretically we show that it is a generalization of PageRank when the heat diffusion coefficient tends to infinity, and empirically we show that it achieves the ability of anti-manipulation. / Predictive Random Graph Ranking (PRGR) incorporates DiffusionRank. PRGR aims to solve the problem that the incomplete information about the Web structure causes inaccurate results of various ranking algorithms. The Web structure is predicted as a random graph, on which ranking algorithms are expected to be improved in accuracy. Experimental results show that the PRGR framework can improve the accuracy of the ranking algorithms such as PageRank and Common Neighbor. / Three special forms of the novel Random Graph Dependency measure on two random graphs are investigated. The first special form can improve the speed of the C4.5 algorithm, and can achieve better results on attribute selection than gamma used in Rough Set Theory. The second special form of the general random graph dependency measure generalizes the conditional entropy because it becomes equivalent to the conditional entropy when the random graphs take their special form-equivalence relations. Experiments demonstrates that the second form is an informative measure, showing its success in decision trees on small sample size problems. The third special form can help to search two parameters in G-HDC faster than the cross-validation method. / Yang, haixuan. / "August 2007." / Advisers: Irwin King; Michael R. Lyu. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1125. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 184-197). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.