The hippocampus is a brain structure involved in episodic memory and spatial cognition. Neuronal activity within the hippocampus exhibits intricate temporal patterning, including oscillatory and sequential dynamics, which are believed to underlie these cognitive processes. In individual cells, a temporal activity pattern called phase precession occurs which leads to the organisation of neuronal populations into sequences. These sequences are hypothesised to form a substrate for episodic memory and the representation of spatial trajectories during navigation. In this thesis, I present a novel theory of the phenomenological properties of these neuronal activity sequences. In particular, I propose that the sequential organisation of population activity is governed by the independent phase precession of each cell. By comparison of models in which cells are independent and models in which cells exhibit coordinated activity against experimental data, I provide empirical evidence to support this hypothesis. Further, I show how independent coding affords a vast capacity for the generation of sequential activity patterns across distinct environments, allowing the representation of episodes and spatial experiences across a large number of contexts. This theory is then extended to account for grid cells, whose activity patterns form a hexagonal lattice over external space. By analysing simple forms of phase coding in populations of grid cells, I show how previously undocumented constraints on phase coding in two dimensional environments are imposed by the symmetries of grid cell firing fields. To overcome these constraints, I propose a more complex phenomenological model which can account for phase precession in both place cells and grid cells in two dimensional environments. Using insights from this theory, I then propose a biophysical circuit mechanism for hippocampal sequences. I show that this biophysical circuit model can account for the proposed phenomenological coding properties and provide experimentally testable predictions which can distinguish this model from existing models of phase precession. Finally, I outline a scheme by which this biophysical mechanism can implement supervised learning using spike time dependent plasticity in order to learn associations between events occurring on behavioural timescales. The models presented in this thesis challenge previous theories of hippocampal circuit function and suggest a much higher degree of flexibility and capacity for the generation of sequences than previously believed. This flexibility may underlie our ability to represent spatial experiences and store episodic memories across a seemingly unlimited number of distinct contexts.

Ma Wing Kin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 150-155). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Law of lien in historical retrospection (especially in real estate matters) Abstract The diploma thesis deals with the historical development of the lien law. The introduction to the issue is devoted to the roman law concept of lien law, as a basic principle of its later formation in central Europe and also in the territory of Bohemia. The following text deals with the right of lien in central Europe from the earliest times to its modification influenced by the reception of roman law with the brief excursion to the reception of roman law. At this point, the reader can recognize a very similar, but somewhat independent, development of lien in central Europe and roman law at the beginning of its development and its stagnation in central Europe. It follows a more detailed analysis of the lien in the Czech lands until the beginning of the 19. th century when the modern civil code of the AGBG began to apply to the territory of most of the Habsburg monarchy (Cislaitania). Subsequently the author of the thesis focuses on the legal regulation of pledge law contained in the AGBG, and also by the draft civil code of 1937 to replace the AGBG. The legal regulation of lien was split into AGBG in several parts of the code, the 1937 proposal corrected this deficiency and made the whole regulation of lien easier to...

by Siu-Lung Hui, Freeman. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 64-[67]). / Abstract also in Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Use of Antenna Arrays in Mobile Communications --- p.1 / Chapter 1.1.1 --- Overview --- p.1 / Chapter 1.1.2 --- Beamforming --- p.2 / Chapter 1.2 --- DS/CDMA System s and Multiple Access Interferences --- p.4 / Chapter 1.3 --- Multiuser Detection Schemes --- p.7 / Chapter 1.4 --- Outline of Thesis --- p.11 / Chapter 2 --- A Blind Adaptive Receiver with Antenna Arrays and M-ary Orthogonal Data Signals --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- System Model --- p.15 / Chapter 2.3 --- Eigen-Analysis Algorithm --- p.21 / Chapter 2.4 --- Simulation Results --- p.92 / Chapter 2.5 --- Adaptive Algorithm --- p.27 / Chapter 2.6 --- Summary --- p.30 / Chapter 3 --- Detection with the Use of the Two-Stage Spreading Scheme --- p.32 / Chapter 3.1 --- Introduction --- p.32 / Chapter 3.2 --- System Model --- p.34 / Chapter 3.3 --- Blind Beamforming --- p.36 / Chapter 3.4 --- Blind Adaptive Multiuser Detection without Antenna Arrays --- p.38 / Chapter 3.4.1 --- Stochastic Gradient Descent Algorithm --- p.40 / Chapter 3.4.2 --- Alternative Matrix Approach --- p.41 / Chapter 3.5 --- Theoretical Combined Receiver Model --- p.41 / Chapter 3.6 --- Practical Implementation of the Receiver --- p.50 / Chapter 3.6.1 --- Combined Scheme with Adaptive Algorithms --- p.50 / Chapter 3.6.2 --- Simplified Structure --- p.52 / Chapter 3.7 --- Summary --- p.54 / Chapter 4 --- Conclusions and Future Work --- p.55 / Chapter A --- Correlation Properties --- p.58 / Chapter B --- Adaptive Algorithm --- p.62 / Bibliography --- p.64

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Magister Theologiae - MTh / South Africa has progressed towards the realisation of an expressive culture of disclosure. Significant implementation and enforcement of the Protected Disclosures Act (26 of 2000 – hereafter referred to as “the Act” or “the PDA”) of South Africa has assisted to enforce the practices and protections provided in terms of the enabling laws and a societal culture which is receptive to and respectful of whistle blowers. This thesis seeks to make a contribution to the discourse on whistle blowing and the PDA from an ethical perspective, by means of using ethical concepts and analysing and discussing ethical dilemmas to provide a greater understanding of the real cases of whistle blowing that has occurred. Various aspects of whistle blowing are defined and reviewed with reference to Hans Jonas’s theory of an ethics of responsibility. One such aspect is the idea of collective responsibility as understood by Hans Jonas. Hans Jonas describes responsibility; in terms of the future responsibility present individuals have as a collective in order to ensure that the future human being are able to actively engage in the world with the same familiarities as is experienced today. This thesis will investigate, more specifically, the contribution made by Hans Jonas’s theory of responsibility in understanding the PDA in terms of an ethics of responsibility. The research question is posed and attempts to discuss and analyse whether Hans Jonas’s theory of an ethics of responsibility may help to identify, analyse and assess ethical issues embedded in the Protected Disclosures Act 26 of 2000.

Este trabalho apresenta uma metodologia de cálculo para a obtenção de doses em estruturas do olho humano, como: esclera, coróide, retina, nervo óptico, corpo vítreo, câmara anterior, lente, além do tumor devido ao tratamento com placas oftálmicas. Construiu-se um modelo de olho humano com suas principais estruturas e dimensões fieis, além de um modelo matemático para uma placa de Co-60 e uma placa de sementes de I-125, levando-se em conta tamanho e disposição geométrica das fontes reais, com o código de Monte Carlo MCNP-4C. Esse modelo é capaz de calcular as distribuições de dose axiais e radiais para qualquer ponto do olho e para cada uma de suas estruturas. Construiu-se, também, um simulador de acrílico para o olho. Esse simulador é formado por uma esfera de acrílico fatiada em lâminas de 1 mm de espessura para simular as mesmas condições de simulação realizada pelos código MCNP-4C, fornecendo as doses axiais e radiais em filmes radiográficos. O simulador foi utilizado para validar os cálculos realizados com o código MCNP-4C. Os dados obtidos desse modelo matemático servirão para montar um banco de dados de doses para todas as estruturas do olho, posições e tamanhos de tumores e quaisquer placas oftálmicas utilizadas para tratamento. Esse banco de dados será a parte principal para a construção de um “software" nacional para cálculos de dose, que poderá fazer parte de um sistema de planejamento confiável para ser utilizado em radioterapia/braquiterapia. / This work presents a calculational methodology for dose determination in human eye structures, such as: sclera, choroid, retina, lens, vitreous body, optic nerve and disc, and cornea, as well as tumor due to treatment to the eye plaques. A human eye model was constructed taking into consideration its main structural and dimension characteristics. Beyond that a mathematical model for the Co-60 and I-125 plaques with all geometric details were built employing the MCNP-4C code. This model is able to calculate the axial and radial doses in any point of the eye and for each of its structures. An acrylic eye simulator was also built with the aim to obtain experimental results for the both model validations. This simulator is made of an acrylic sphere split into foils of 1 mm thickness which allow the introduction a radiographic film to measure the axial and radial doses. The experimental data were used to validate the MCNP-4C results. The data from the mathematical model will serve as the basis to build a data bank for all the eye structures allowing different position and sizes of tumor as well as the replacement of all ophthalmic plaques used in the treatment. This data bank will be the principal part for the construction of a national software for the dose calculation and can be of great help for a reliable treatment system planning in radiotherapy/brachytherapy.

Determinar o melhor conjunto de otimizações para serem aplicadas a um programa tem sido o foco de pesquisas em otimização de compilação por décadas. Em geral, o conjunto de otimizações é definido manualmente pelos desenvolvedores do compilador e aplicado a todos os programas. Técnicas de aprendizado de máquina supervisionado têm sido usadas para o desenvolvimento de heurísticas de otimização de código. Elas pretendem determinar o melhor conjunto de otimizações com o mínimo de interferência humana. Este trabalho apresenta o ML4JIT, um arcabouço para pesquisa com aprendizado de máquina em compiladores JIT para a linguagem Java. O arcabouço permite que sejam realizadas pesquisas para encontrar uma melhor sintonia das otimizações específica para cada método de um programa. Experimentos foram realizados para a validação do arcabouço com o objetivo de verificar se com seu uso houve uma redução no tempo de compilação dos métodos e também no tempo de execução do programa. / Determining the best set of optimizations to be applied in a program has been the focus of research on compile optimization for decades. In general, the set of optimization is manually defined by compiler developers and apply to all programs. Supervised machine learning techniques have been used for the development of code optimization heuristics. They intend to determine the best set of optimization with minimal human intervention. This work presents the ML4JIT, a framework for research with machine learning in JIT compilers for Java language. The framework allows research to be performed to better tune the optimizations specific to each method of a program. Experiments were performed for the validation of the framework with the objective of verifying if its use had a reduction in the compilation time of the methods and also in the execution time of the program.

Component-based development is an approach that revolves around the construction of systems form pre-built modular units (components). If legacy code can be reverse engineered to extract components, the extracted components can provide architectural re-usability across multiple systems of the same domain. Current component directed reverse engineering approaches are based on component models that belong to architecture description languages (ADLs). ADL-based components cannot be reused without configurational changes at code level and binding every required and provided service. Moreover, these component models neither support code-independent composition after extraction of components nor the re-deposition of a composed configuration of components for future reuse. This thesis presents a reverse engineering approach that extracts components and addresses the limitations of current approaches, together with a tool called RX-MAN. Unlike ADL-based approaches, the presented approach is based on an encapsulated component model called X-MAN. X-MAN components are encapsulated because computation cannot go outside of a component. X-MAN components cannot interact directly but only exogenously (composition is defined outside of a component). Our approach offers code-independent composition after extracting components and does not need binding of all the services like ADLs. The evaluation of our approach shows that it can facilitate the re-usability of legacy code by providing code-independent composition and re-deposition of composed configurations of components for further reuse and composition.

Hu Fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 77-81). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.ii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Evolution of Mobile Communications --- p.1 / Chapter 1.2 --- Overview of Multicarrier Systems --- p.3 / Chapter 1.3 --- Outline of This Thesis --- p.5 / Chapter 2 --- Multicarrier Communication Systems --- p.7 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Multicarrier Modulation (MCM) Scheme versus Single Carrier Modulation (SCM) Scheme --- p.8 / Chapter 2.3 --- Orthogonal Frequency Division Multiplexing (OFDM) Systems --- p.12 / Chapter 2.4 --- Multicarrier CDMA --- p.16 / Chapter 2.4.1 --- MC-CDMA --- p.17 / Chapter 2.4.2 --- MC-DS-CDMA --- p.18 / Chapter 2.4.3 --- MT-CDMA --- p.19 / Chapter 3 --- Optimization for MC-CDMA Systems --- p.22 / Chapter 3.1 --- System Model --- p.22 / Chapter 3.2 --- Optimization with Normalized Power --- p.27 / Chapter 3.2.1 --- Transmission Time Minimization --- p.27 / Chapter 3.2.2 --- Throughput Maximization --- p.32 / Chapter 3.2.3 --- Performance --- p.33 / Chapter 3.3 --- Mathematical Programming --- p.36 / Chapter 3.3.1 --- Nonlinear Programming --- p.37 / Chapter 3.3.2 --- Convex Programming --- p.39 / Chapter 3.4 --- Optimization with Power Allocation --- p.42 / Chapter 3.4.1 --- Transmission Time Minimization with Power Allocation --- p.42 / Chapter 3.4.2 --- Throughput Maximization with Power Allocation --- p.43 / Chapter 3.4.3 --- Power Minimization --- p.44 / Chapter 3.5 --- Long-range Optimization --- p.45 / Chapter 3.5.1 --- Long-range Transmission Time Minimization --- p.46 / Chapter 3.5.2 --- Long-range Throughput Maximization --- p.50 / Chapter 3.5.3 --- Long-range Power Minimization --- p.51 / Chapter 3.5.4 --- Performance --- p.53 / Chapter 4 --- Joint Scheduling and Resource Allocation --- p.58 / Chapter 4.1 --- Queueing Model --- p.58 / Chapter 4.2 --- Problem Formulation --- p.62 / Chapter 4.3 --- Suboptimal Algorithm --- p.64 / Chapter 4.4 --- Performance --- p.69 / Chapter A --- Convexity Proof of Problem (3.32) --- p.73 / Chapter B --- Convexity Proof of Problem (3.36) --- p.75 / Bibliography --- p.77