Theses

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  • A Block Cipher Design Using Recurrent Neural Networks
    A Block Cipher Design Using Recurrent Neural Networks
    As security becomes a necessary component for business applications in many areas, research of new cryptography technology is desirable, especially the highly secure and efficient data encryption technique. A new block cipher designed [sic] based on recurrent neural networks is proposed for the first time in the project. Recurrent neural networks have dynamics characteristics and can express functions of time. By introducing recurrent neural networks to cryptography, the proposed block cipher releases the constraint on the the length of secret key. The inherited high by parallel processing capability of neural networks can also improve the encryption performance greatly. The recurrent neural networks make the block cipher strong to resist different cryptanalysis attacks and to provide data integrity and authentication service at the same time. The design of the proposed block cipher is presented and analysed in detail. Simulation results provide illustrations. The proposed block cipher is flexible to be implemented either in software or in hardware for efficient data encryption purpose.
    A Blueprint for Recovery
    A Blueprint for Recovery
    Built environments inevitably serve as grand mnemonic elements that contain and transmit layers of culture and history. Failing to acknowledge the significance of difficult memories in the identity and culture of cities induces the gradual erosion of history as well as preventing movement toward a better future. In order to preserve the latent value in the identity of the city, architectural strategies should be implemented by which forgotten memories and hidden traces could be recalled to conscious narration. Recalling a story from the past, intentionally or unconsciously forgotten as a form of amnesia, can help re-contextualize memory images that awaken within us a new avenue to the future. This thesis intends to refine the dynamics of remembrance, illuminating the power of architecture as a medium for providing frames of perception and horizons of understanding of past experiences.
    A CAVE based 3d immersive interactive city with gesture interface
    A CAVE based 3d immersive interactive city with gesture interface
    This thesis presents a system that visualizes 3D city data and supports gesture interactions in a fully immersive Cave Automatic Virtual Environment (CAVE). To facilitate more natural interactions in this immersive virtual city, novel techniques are proposed for operations such as object selection, object manipulation, navigation and menu control. These operations form a basis of interactions for most Virtual Reality (VR) applications. The proposed techniques are predominantly controlled using gestures. We also propose the use of pattern recognition methods, specifically a Hidden Markov Model, to support real time dynamic gesture recognition and demonstrate its use for menu control in VR applications. Qualitative and quantitative user studies are conducted to evaluate the proposed techniques. The results of the user studies demonstrate that the interaction techniques for object selection and manipulation are measurably better than traditional techniques. The results also show that the proposed gesture based navigation and menu control techniques are preferred by experienced users. These findings can guide future user interface design in immersive environments.
    A CMOS voltage-mode image sensing system
    A CMOS voltage-mode image sensing system
    A CMOS image sensor consists of a light sensing region that converts photonic energy to an electrical signal and a peripheral circuitry that performs signal conditioning and post-processing. This project investgates the principle and design of CMOS active image sensors. The basic concepts and principle of CMOS image sensors are investigated. The advantages of CMOS image sensors over charge-coupled device (CCD) image sensors are presented. Both passive pixel sensors (PPS) and acive pixel sensors (APS) are examined in detail. The noise of CMOS image sensors is investigated and correlated double sampling (CDS) techniques are examined. The design of APS arrays, CDS circuits and 8-bit analog to-digital converters in TSMC-0.18μm 1.8V CMOS technology is presented. The simulation results and layout of the designed CMOS image sensor are presented.
    A Case Study in Actual Building Performance and Energy Modeling with Real Weather Data
    A Case Study in Actual Building Performance and Energy Modeling with Real Weather Data
    As part of this study, an issue has been identified with regards to there being a performance gap with energy efficient buildings. This has been validated through literature review in the areas of occupancy behavior, modeling accuracy and reviewing energy consumption of energy efficient buildings. In order to analyze the error generated between predicted and actual energy performance, a case study approach has been adopted. The Ron Joyce Centre is a LEED Gold Certified building that is part of the McMaster University campus in Burlington. Actual energy performance data has been collected along with detailed drawings to analyze its predicted energy performance using real weather data over a two-year period in eQUEST. The results indicate that eQuest is able to predict electrical consumption within 0.72% of actual on an annual basis. However, natural gas consumption is more erratic and inconsistent based on heating degree days and has fluctuating values with differences ranging between 21% to 4.5% on monthly basis. The overall predicted energy consumption for 2012 is 1096133 kWh and 33227 m3. It is not possible to root the cause for this discrepancy with limited data, except to utilize two weather files in generating energy models. The default 30 year average from CTMY for Toronto and another to account for the maximum number of HDD, offering owners a range of natural gas consumption.
    A Case-Study Comparison Towards Quantifying Energy Saving Strategies in Big-Box Retail Stores
    A Case-Study Comparison Towards Quantifying Energy Saving Strategies in Big-Box Retail Stores
    This research focuses on energy-related initiatives implemented by one big-box retail chain in Canada. Through analysis of energy reduction strategies, the study compares the energy performance of two stores, one of which operated with conventional design features and the other which was operated with energy-related upgrades. The results of this research conclude that the store constructed with advanced technological solutions outperformed the other in terms of energy-use intensity by 44%. The research also reveals that premium costs related to the advanced technologies were effective choices. For example, the upgraded mechanical strategy showed an ROI of 52% and a simple payback of 2 years. Finally, the research analyzes initiatives that are currently under evaluation by some of North America’s largest retail companies. The results show further energy efficiency opportunities in areas such as retail lighting and plug load reduction strategies, with each offering further reductions of 3% and 2-4% respectively.
    A Channel Based Fair Scheduling Scheme For Downlink High Speed Data In CDMA Networks
    A Channel Based Fair Scheduling Scheme For Downlink High Speed Data In CDMA Networks
    High speed data transmission in wireless networks demands better radio resource management schemes. The research work for this thesis considers packet scheduling in downlinks of a cellular CDMA system for delay-tolerant applications. In this thesis, a packet scheduling scheme is proposed that attempts to provide fair allocation of individuals throughout and obtain relatively high system throughput. It is based on combined consideration of channel conditions, required throughput and achieved average throughput. A priority factor and system tolerance factor are introduced. We confirmed the trade-off between system throughout (i.e., efficiency) and individual throughput (i.e., fairness) by both analysis and simulation. Relative performance between the proposed scheme and traditional schemes is evaluated through simulation to confirm the analytical observations. The sensitivity of system tolerance factor towards efficiency and fairness was also investigated. Overall, the proposed scheme performs between absolute unfairness scheme and absolute fairness scheme in term s of system throughput and fair allocation of individual throughput.
    A Cluster-Based Browsing Model For QoS-Aware Web Service Selection
    A Cluster-Based Browsing Model For QoS-Aware Web Service Selection
    In the last decade, selecting suitable web services based on users’ requirements has become one of the major subjects in the web service domain. Any research works have been done - either based on functional requirements, or focusing more on Quality of Service (QoS) - based selection. We believe that searching is not the only way to implement the selection. Selection could also be done by browsing, or by a combination of searching and browsing. In this thesis, we propose a browsing method based on the Scatter/Gather model, which helps users gain a better understanding of the QoS value distribution of the web services and locate their desired services. Because the Scatter/Gather model uses cluster analysis techniques and web service QoS data is best represented as a vector of intervals, or more generically a vector of symbolic data, we apply for symbolic clustering algorithm and implement different variations of the Scatter/Gather model. Through our experiments on both synthetic and real datasets, we identify the most efficient ( based on the processing time) and effective implementations.
    A Comparative Analysis Of MEMS Parallel Plate Actuators
    A Comparative Analysis Of MEMS Parallel Plate Actuators
    The purpose of this study is to compare the deformation of the moving top plate of five distinct parallel plate capacitor designs under applied voltage as well as compare the pull-in voltage of each design. The parallel plate designs are created using AutoCAD 2008 software and the simulations are performed using CoventorWare 2010. The control design is first validated with known results and then compared to the remaining four designs. Finally, pull-in voltages of all five designs is determined and compared to determine the advantages and disadvantages of each design.
    A Comparative Investigation In Measuring Food Access: Food Deserts In Urban Setting
    A Comparative Investigation In Measuring Food Access: Food Deserts In Urban Setting
    An increasing number of food desert studies over the past two decades have attempted to identify urban areas with inadequate access to nutritious and affordable food with implications for public health social equity and environmental issues. Due to different ways of operationalizing food desert analysis and the multifaceted dimension of the concept, there are inherent ambiguities in the validity and accuracy of food desert results across different studies. This study challenged the conventional measurements of food availability (e.g., distance-to-supermarket criterion) and food accessibility (e.g., circular buffer method) in identifying food deserts. An alternative methodology was developed that considered a wider variety of healthy food sources and used a network buffer method to produce more comprehensive results. Using Geographic Information System (GIS) analysis, alternative measures of food deserts were tested empirically in one Toronto ‘disadvantaged’ neighborhood. The results indicated that different areas were identified as part of a food desert depending on the methodology used. It concludes that failing to use a broader set of food desert elements can significantly alter the results in the study area.
    A Comparative Study of Formation Control at the Earth-Moon L₂ Libration Point
    A Comparative Study of Formation Control at the Earth-Moon L₂ Libration Point
    This thesis examines the performance of control methods that fall under the optimal, predictive and adaptive classifications, subjected to sensor/actuator faults, and presents approaches to apply them to non-affine systems utilizing single thruster and solar sail actuator configurations. The system of interest consists of a leader-follower satellite formation near the L2 point of the Earth-Moon system. The control methods studied here include those which are emerging in the space systems literature, and are evaluated in terms of their transient and steady state responses, and control input variation. Numerical simulation of faults affecting both sensor and propulsion actuator systems are conducted, along with an experiment to validate the results in a laboratory environment. The observed behavioral characteristics in the simulations match those demonstrated in the experiment. Alternative representations of dynamics were explored for controller design of non-affine systems. The research presented herein provides support for the usage of the proposed control strategies in future space applications.
    A Comparison Of Building Envelope Performance Levels Between Ontario, Denmark, Germany And The Passive House Standard, In The Low-Rise, Residential Context
    A Comparison Of Building Envelope Performance Levels Between Ontario, Denmark, Germany And The Passive House Standard, In The Low-Rise, Residential Context
    This research compared and analyzed where the Ontario Building Code rates in the low-rise, residential sector in terms of its: Current and past building envelope regulation requirements,‘Typical’ building envelope connection details,Current building envelopes regulation requirements in energy consumption and‘Typical’ building envelopes energy consumptionin comparison to Denmark, Germany and the Passive House Standard. This was analyzed to see how Ontario compared against other world renowned energy efficient regulations and where or if there was room for improvement. For this, HOT2000 and THERM were utilized on all four of the reference standards, where both of these programs were managed in a way to compare the results of ‘typical’ building envelopes and the current regulation from each of the standards. These results were then able to provide a whole home’s heating and air conditioning energy use in the Greater Toronto Area climate. Overall, the results illustrated Ontario homes consume the most energy for both typically constructed homes and homes utilizing the minimum requirements. In addition to this, Ontario also had the least performing building envelope connection details. In total, the Passive House performed at the highest level followed by Germany, Denmark and then Ontario.