A series of complex digital blocks have been designed and fabricated using the newly developed current-mode differential CMOS logic family viz. the Folded Source-Coupled Logic ( FSCL ). The main feature of this logic family is the low current spikes generated during the switching transitions ( at least 2 orders of magnitude smaller than the conventional static CMOS gates ). The design of a decimation filter using novel Multi-Rate systolic architecture and it's implementation in Folded Source-Coupled Logic is also considered. The decimation filter thus designed can be used in mixed-mode applications like Sigma-Delta A/D converter to improve it's performance characteristics like dynamic range, resolution and phase linearity at higher sampling rates. / Graduation date: 1992

Fully efficient systolic arrays for the solution of Toeplitz matrices using Schur algorithm [1] have been obtained. By applying clustering mapping method [2], the complexity of the algorithm is 0(n) and it requires n/2 processing elements as opposed to n processing elements developed elsewhere [1]. The motivation of this thesis is to obtain efficient pipeline arrays by using the synthesis procedure to implement Toeplitz matrix solution. Furthermore, we will examine pipeline structures for the Toeplitz system factorization and back-substitution by obtaining clustering and Multi-Rate Array structures. These methods reduce the number of processing elements and enhance the computational speed. Comparison and advantage of these methods to other method will be presented. / Graduation date: 1992

Acquisition of 3D model of real objects and scenes is indispensable and useful in many practical applications, such as digital archives, game and entertainment industries, engineering, advertisement. There are 2 main methods for 3D acquisition : laser-based reconstruction (active method) and image-based reconstruction from multiple images of the scene in different points of view (passive method). While laser-based reconstruction achieves high accuracy, it is complex, expensive and difficult to set up for large-scale outdoor reconstruction. Image-based, or multi-view stereo methods are more versatile, easier, faster and cheaper. By the time we begin this thesis, most multi-view methods could handle only low resolution images under controlled environment. This thesis targets multi-view stereo both both in large scale and high accuracy issues. We significantly improve some previous methods and combine them into a remarkably effective multi-view pipeline with GPU acceleration. From high-resolution images, we produce highly complete and accurate meshes that achieve best scores in many international recognized benchmarks. Aiming even larger scale, on one hand, we develop Divide and Conquer approaches in order to reconstruct many small parts of a big scene. On the other hand, to combine separate partial results, we create a new merging method, which can merge automatically and quickly hundreds of meshes. With all these components, we are successful to reconstruct highly accurate water-tight meshes for cities and historical monuments from large collections of high-resolution images (around 1600 images of 5 M Pixel images)

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MU-MIMO theory predicts manyfold capacity gains by leveraging many antennas (e.g. M >> 10) on wireless base stations to serve many users simultaneously through multi-user beamforming (MUBF). However, realizing such a large-scale design is nontrivial, and has yet to be achieved in the real world. We present the design, realization, and evaluation of Argos, the first reported large-scale base station that is capable of serving many (e.g., 10s of) terminals simultaneously through MUBF. Designed with extreme flexibility and scalability in mind, Argos exploits hierarchical and modular design principles, properly partitions baseband processing, and holistically considers real-time requirements of MUBF. To achieve unprecedented scalability, we devise a novel, completely distributed, beamforming technique, as well as an internal calibration procedure to enable implicit beamforming across large arrays. We implement a prototype with 64 antennas, and demonstrate that it can achieve up to 6.7 fold capacity gains while using a mere 1/64th the transmission power.

This thesis reports on the procedure, results and analysis of four full scale fire tests that were performed at the University of Waterloo's Live Fire Research Facility. The purpose of these tests was to investigate the thermal characteristics of one room of the Burn House structure. Comparisons were made of Burn House experimental data to previous residential fire studies undertaken by researchers from the University of Waterloo. This analysis showed similarities in growth rate characteristics, illustrating that fire behaviour in the Burn House is typical of residential structure fire behaviour. The Burn House experimental data was also compared to predictions from a fire model, CFAST. Recommendations were made for future work in relation to further investigation of the fire characteristics of the Burn House.

Experiments were conducted to investigate the macroscopic thermal behaviour of 2m diameter Jet A fires in crosswinds of 3m/s to 13m/s. Two scenarios were considered: with and without a 2.7m diameter, 10.8m long, blocking object situated 3.4m downwind of the fire. These scenarios simulated transportation accidents with the fire representing a burning pool of aviation fuel and the object simulating an aircraft fuselage. To date, the limited number of experiments that have been conducted to examine wind effects on fire behaviour have been performed at small scale, which does not fully simulate the physics of large fires, or in outdoor facilities, with poorly controlled wind conditions. This thesis presents the first systematic characterization of the thermal environment in a large, turbulent fire under controlled wind conditions, with and without a large downwind blocking object. In experiments without the object, flame geometry was measured using temperature contour plots and video images, and the results compared to values predicted using published correlations. Results were greatly affected by the method used to measure flame geometry and by differences in boundary conditions between experiments. Although the presence of the blocking object prevented direct measurement of flame geometry due to interaction between the fire plume and object, temperature and heat flux measurements were analyzed to describe overall effects of the object on fire plume development. The fire impinged on the blocking object at wind speeds below 7m/s and interacted with the low-pressure wake region behind the object. Laboratory-scale experiments were also conducted to examine the responses of different heat flux gauges to controlled heating conditions simulating those found in wind-blown fires. Schmidt-Boelter, Gardon and Hemispherical Heat Flux gauges and a Directional Flame Thermometer were exposed to a convective flow and to radiation from a cone calorimeter heater. Measurements were influenced by differences between the calibration and measurement environments, differences in sensor surface temperature, and unaccounted thermal losses from the sensor plate. Heat flux results from the fires were consistent with those from the cone calorimeter, but were additionally affected by differences in location relative to the hot central core of the fire.

This work details an O(n^2) algorithm for computing the spectra of discrete Schroedinger operators with periodic potentials. Spectra of these objects enhance our understanding of fundamental aperiodic physical systems and contain rich theoretical structure of interest to the mathematical community. Previous work on the Harper model led to an O(n^2) algorithm relying on properties not satisfied by other aperiodic operators. Physicists working with the Fibonacci Hamiltonian, a popular quasicrystal model, have instead used a problematic dynamical map approach or a sluggish O(n^3) procedure for their calculations. The algorithm presented in this work, a blend of well-established eigenvalue/vector algorithms, provides researchers with a more robust computational tool of general utility. Application to the Fibonacci Hamiltonian in the sparsely studied intermediate coupling regime reveals structure in canonical coverings of the spectrum that will prove useful in motivating conjectures regarding band combinatorics and fractal dimensions.

This thesis reports on the procedure, results and analysis of four full scale fire tests that were performed at the University of Waterloo's Live Fire Research Facility. The purpose of these tests was to investigate the thermal characteristics of one room of the Burn House structure. Comparisons were made of Burn House experimental data to previous residential fire studies undertaken by researchers from the University of Waterloo. This analysis showed similarities in growth rate characteristics, illustrating that fire behaviour in the Burn House is typical of residential structure fire behaviour. The Burn House experimental data was also compared to predictions from a fire model, CFAST. Recommendations were made for future work in relation to further investigation of the fire characteristics of the Burn House.