identifier: Zhang, Qinghui  (2005) Mumford-Shah model and its application in image processing.  Masters thesis, Concordia University.

abstract: The Mumford-Shah (MS) model has been studied in details in this thesis. It is found that the piecewise constant approximation MS model can not be used for images with large variation in the intensities. Therefore a linear approximation MS model is introduced. We have found that the linear approximation MS model provides better segmentation results than the piecewise constant MS model. The level set methods are used in the numerical computations. We have explicitly proved that the MS energy decreases with time (iterations) for all cases. The o and p dependence of the MS model is also studied. It is found that when o becomes large, the piecewise constant model is recovered. On the other hand, if o tends to zero, detailed structure of the input image can be obtained by the MS segmentation model. The MS and the Rudin-Osher-Fatemi (ROF) like models are generalized to include high order derivative terms. It is found that this kind of model can be used for edges with low contrast. The MS model is also generalized to a new model which can be used to detect roof edges which are difficult to detect by other models. Verification of the proposed models is done based on experimental results


identifier: Wang, Shengjian  (2005) Efficient multicast routing algorithms for mesh-connected multicomputers.  Masters thesis, Concordia University.

type: Thesis NonPeerReviewed

abstract: Multicast is a collective communication method in which a message is sent from a source to an arbitrary number of distinct destinations. Multicomputers refer to massively parallel computers that consist of thousands of processors built to handle computation intensive applications. Mesh is a kind of network topology widely used in multicomputers. Performance of multicomputers largely depends on that of the underlying network communications such as multicast, which is essential for processors to exchange data and messages. Two major parameters used to evaluate multicast routing are the time it takes to deliver the message to all destinations and the traffic which refers to the total number of links involved. Research indicated that these two parameters are normally not independent, but contradict each other. It has been proved that traffic optimal multicast problems such as Optimal Multicast Path/Tree in mesh-connected network are NP-complete. Hence, it is NP-hard to find multicast routing which is optimal on both time and traffic. In this thesis, we proposed three efficient multicast routing algorithms for mesh-connected multicomputers: DIAG, DDS and XY-path, all of which have a small complexity of O(KN) or less. The DIAG and DDS are two tree-based shortest path multicast routing algorithms designed for store-and-forward switched mesh network, which obtained near optimal time and reduced traffic significantly over its predecessor VH algorithm. XY-path is a dual-path-based multicast routing algorithm intended for wormhole routed 2D mesh network, which reduced the time and traffic significantly over LIN's Hamiltonian path-based algorithm. Performance evaluations of these algorithms resulted from simulations are given at the end of the thesis.


identifier: Yousefi, Jamileh  (2005) Using reformulations to improve question answering.  Masters thesis, Concordia University.

abstract: This project has two major goals. In the first phase, we present a method for the automatic acquisition of reformulations from natural language questions. We hope to find useful and generic reformulation patterns, which can be used in our question answering system to find candidate answers. We use some examples of different types of questions and their right answers as training set and the system automatically extracts the patterns from retrieved documents. The system also calculates and assigns a weight to each of the extracted patterns. These patterns are added to the patterns set of the current Web-QA component. In the second part, we present a method to filter out noisy candidate answers and re-rank candidate answers in our Web-QA module by using semantic relations. We use the original Web-QA module of QUANTUM and developed the Web-QA2 module for this thesis. We use the 1400 questions of the TREC-8, TREC-9, and TREC-10 competitions for training to develop the reformulation patterns and the filtering algorithm and use the 500 questions of TREC-11 for testing.


identifier: Li, Qiao  (2005) XML-based context maps and CMapViewer application.  Masters thesis, Concordia University.

abstract: Context maps are a kind of high-level notational technology which has been increasingly used in information system and software engineering over the last few years. Recent efforts using Microsoft (MS) Excel spreadsheets to represent the context maps have shown some progress toward meeting the various needs for the development of context maps. However, as more applications developed for the manipulation of context maps, complying with the technical requirements imposed by MS Excel limits their functionalities and further development. Extensible Markup Language (XML) and related technologies may be used to help to overcome current limitations. This thesis introduces a new way of XML-based context maps to represent formatted knowledge. Structured information stored in XML format is very easily exchanged among different applications. This makes XML a natural choice to be used as a representation format for the context maps. A Java-based application named CMapViewer has been developed to view and manipulate the XML-based context maps and it demonstrates an easy, intuitive and powerful solution for manipulating the formatted knowledge. In addition, an appropriate tool has been developed to allow users to transform current context map documents into the XML-based formats. This service demonstrates the implementation of solutions for the interoperability of XML-based context maps.


identifier: Plouffe, Frédéric  (2005) DoxyChange : visualization of software changes.  Masters thesis, Concordia University.

abstract: Visualization techniques are often used when a legacy software system becomes nearly unmaintainable, in which case software visualization can be applied to regain an understanding of the software system, such that maintenance activities can take place. One of such visualization techniques consists of identifying how a given module ended up in its current state. Therefore by visualizing the history of the source code repository, it may be possible to visualize software changes and understand how the software system has evolved over time. The presented work, which is part of the CONCEPT framework (Comprehension Of Net-CEntered Programs and Techniques) [RIL03], applies visualization techniques to any of the diagrams generated by Doxygen [HEE05] from the retrieved source code repository, in order to display software changes between two specified revisions. The graphics are obtained by reusing the powerful Graphviz Dot [GAN00] layout algorithm, which enables software engineers to easily grasp the complexity of a given module and facilitate the task of program comprehension by visualizing the system at a higher level of abstraction. Moreover, this project addresses some of the shortcomings, found in some reverse engineering tools, by providing an intuitive navigation and interaction within the generated UML diagrams. Finally, this research project is aimed to be use by any projects, which are currently using Doxygen as an online documentation tool [HEE05p], with the hope to bring visualization of software changes to these developers


identifier: Shan, Xunying  (2005) Characterization of a temperature-sensitive mutation that impairs the function of yeast tRNA nucleotidyltransferase.  Masters thesis, Concordia University.

abstract: Mature tRNAs require a 3'-terminal cytidine-cytidine-adenosine sequence to function in protein synthesis. The addition of these nucleotides into tRNAs with incomplete 3'-termini is catalyzed by the enzyme tRNA nucleotidyltransferase. Genetic studies have resulted in the isolation of the gene coding for tRNA nucleotidyltransferase in yeast and in vivo studies identified a temperature-sensitive yeast strain with a mutant CCA1 gene, which can survive at room temperature, but not at 37{493}C. Gene sequencing revealed that the temperature-sensitive phenotype came from a single nucleotide substitution in the CCA1 gene, which led to the substitution of a glutamate residue by a lysine in the protein (D. Kushner, personal communication). In this work, enzymatic characterization showed that this lysine variant had approximately 5% of the activity of the wild-type enzyme and a tertiary structural change as detected by fluorescence spectroscopy at the permissive temperature. Thermal stability monitored by circular dichroism showed that the lysine variant is less thermally stable than the wild-type enzyme with an approximately 6{493}C lower transitional temperature.


identifier: Malla, Pratibha  (2005) Structural analysis of N-phenyl-N'-sulfinylhydrazines and their hydrogen bonded dimers.  Masters thesis, Concordia University.

abstract: N-phenyl-N'-sulfinylhydrazine (PhNHNSO) is known to form hydrogen bonded dimers in the solid. Recent experimental studies have shown that the dimerization of PhNHNSO is very sensitive towards the position of a substituent on the aromatic ring. It was found that upon introduction of a substituent in ortho position, dimerization did not occur. However, substitution in meta and para position did not hinder dimer formation.  This study was carried out to understand why certain PhNHNSOs dimerize, while others do not. The effects of substituent and solvent on dimerization were investigated by means of different computational methods. In general, density-functional theory calculations were combined with topological analyses of the electron density.  The relative energies revealed a preference of the syn configuration over other configurations of the unsubstituted monomer. The introduction of substituents in ortho position led to less stable monomers as well as dimers, whereas meta and para substitution had only a small effect on monomer and dimer stabilities. The geometries, frequencies and electron densities of N-H and S=O bonds are more affected by ortho than by meta and para substitution, and the ortho dimers showed weaker intermolecular interactions because of twisted geometries. The observed intermolecular N-H---O and C-H---O interactions in the dimers are characterized as hydrogen and anti-hydrogen bonds, respectively. Increasing solvent polarity weakens the dimers. The topological properties, structural parameters and energies showed an unfavourable dimerization for ortho substituted PhNHNSO monomers, which is consistent with the experimental results


identifier: Huang, Shan  (2005) Solar-driven vapor flow in wood-frame walls with wetted cladding.  Masters thesis, Concordia University.

abstract: Solar radiation on wet porous claddings may produce inward vapour flow and condensation. In warm and humid climates, such phenomenon must be considered in the building envelope design. Although no major failure due to solar-driven moisture condensation in cold climates have been reported, such moisture transport may occur, and it is not known to what extent summer condensation must be prevented in Canadian climates. The objective of the project presented in this thesis is to investigate the phenomenon and the factors that influence it. The thesis presents an experimental protocol including test specimen design, monitoring instrumentation and loading conditions. Varied parameters include a wet cladding subjected to simulated solar radiation, location of the vapour retarder and ventilation of the air cavity. Solar radiation is simulated using heat lamps. Experimental results on the hygrothermal performance of walls with wet cladding subjected to simulated solar radiation are presented. Experimental results are further analyzed with the dew-point method and a commercial heat and mass transport model.


identifier: Roos, K. Pieter  (2005) Two sphere immunoassay on a microfluidic device.  PhD thesis, Concordia University.

abstract: Clinical measurements of biologically important proteins and peptides are routinely carried out in the laboratory setting using immunoassays. However, the most recent trend in medicine is the advance of personalized medicine. The goal is to tailor the diagnosis, care and the drugs to the individual. To make this a reality, fast and inexpensive, analytical tools need to be developed that are capable of measuring multiple biological markers at one time in small volumes. When an assay can use very small volumes less invasive methods for obtaining samples such as blood can be used (finger prick). The measurement of more than one biomarker from the same sample using the traditional ELISA method requires a separate immunoassay for each analyte. This is expensive, requires large amount of sample and is time consuming. A faster and more economical way is by developing a multiplexing assay where not one but several analytes are measured at one time. The immunoassay we developed uses microspheres (capture spheres) conjugated with monoclonal antibodies specific to the targeted analyte. These microspheres capture the antigen and form a microsphere-antibody-antigen complex, which are then bound by a secondary monoclonal antibody, recognizing a different exposed epitope on the antigen. This secondary antibody is conjugated to a second microsphere (detection sphere). The capture and detection spheres are loaded with fluorescent dyes, each with a different wavelength, allowing for easy differentiation. Detection of the capture sphere-antigen-detection sphere complexes can accomplished by three different formats, 96 well plate, Flow cytometer and Microfluidic devices. In this Thesis we will discuss the development of this fast and sensitive aminoassay using these three formats. We will show that the assay can be performed in less then 15 minutes with sensitivity comparable to, or better than that obtained with the gold standard ELISA assay. Also we will calculate the theoretical limits of this assay and compare them to a commercial single bead assay


identifier: Wang, Fang  (2005) On-site labor productivity estimation using neural networks.  Masters thesis, Concordia University.

abstract: This thesis presents a study of on-site labor productivity in building construction using the work sampling method. The study is based on a field investigation of a number of selected construction operations on three buildings in Montreal, Quebec, Canada. The developed models revealed related parameters' impact on labor productivity. Neural network was used as a method for the development of the models presented in this thesis. The developed models are based on the data collected using work sampling and were developed using NeuralShell2 software. The network was trained and tested using 221 data points collected from real construction projects that were performed in Montreal in a 30-month period. The models' development and validation utilize real-world data from the projects. Three types of neural network-based models were developed. The first type of models is back propagation neural network (BPNN) models associated with different settings. The fifth model has shown the best results.


identifier: Liao, Liang  (2005) Numerical and experimental investigation of building-integrated photovoltaic-thermal systems.  Masters thesis, Concordia University.

abstract: This thesis presents a numerical and experimental study of a building-integrated photovoltaic-thermal (BIPV/T) system in Concordia University, which generates both electricity and thermal energy. A 2-D computational fluid dynamics (CFD) model is developed to study the air dynamics and thermal behavior inside the BIPV thermal system and develop relationships for convective heat transfer coefficients. A 2-D k-ϵ turbulent model is used in the FLUENT program to simulate the turbulent flow and convective heat transfer in the cavity, in addition to the buoyancy effect. Longwave radiation between boundary surfaces is also modeled. Experimental measurements taken in a full scale outdoor test facility at Concordia University are in good agreement with the 2-D CFD model. Velocity and temperature profiles for various average air velocities are predicted and compared with experimental data. Particle Image Velocimetry (PIV) is employed to investigate the velocity profile. Average and local convective heat transfer coefficients are generated for the system


identifier: Zhang, Zhong-Hong  (2005) Measurement of diffusion and partition coefficients of VOCs in dry building materials.  Masters thesis, Concordia University.

abstract: Building materials, as a source of contaminant, such as volatile organic compounds (VOCs), and a sink of those pollutants, can significantly affect indoor air quality (IAQ). Physical models have been developed to predict volatile organic compound emissions from building materials. These results are helpful in adopting strategies to control the pollutant source. Therefore, experimental methods have been established for measuring input parameters to these models, such as diffusion coefficient (D), partition coefficients (K). However, currently available data of diffusion and partition coefficients are limited. Moreover, the effects caused by the physicochemical properties of VOC are not completely observed. Hence, it is requisite that a comprehensive investigation on the relationship between diffusion and partition coefficients, and the physicochemical properties of VOC be conducted. The twin chamber method was chosen in this research. The effects caused by physicochemical properties of VOC, such as molecular weight, vapor pressure, boiling point, and polarity, were investigated.


identifier: Baetu, Tudor  (2005) Truth, falsity and experimental science.  Masters thesis, Concordia University.

title: Truth, falsity and experimental science

abstract: The arguments presented in this thesis aim to show that a Kantian model in which a theoretical framework is constitutive of empirical reality denies the possibility of a full grown experimental science. In contrast, a logical empiricist model according to which empirical reality is described by means of a theoretical language such as Euclidian geometry or Newtonian mechanics allows for a possible disagreement between experiment and theory. One of the main strengths of this model consists in its ability to handle cases in which theory is shown to be false in respect to empirical reality. However, in order to achieve this compatibility with experimental science, I argue that we must abandon the assumption that there is a single, unified language of science and replace it with the more general assumption of a plurality of languages. Under this new formulation, a perfect unity of science cannot be granted solely by a coherent formulation of all scientific knowledge in a unique language of science, but must be complemented by the common reference of all scientific theories to the same empirical reality


identifier: Zhan, Guoshun  (2005) Power transients in fiber raman amplifiers with coherent pumping or incoherent pumping.  Masters thesis, Concordia University.

abstract: We investigate power transient effect caused by channel addition/removal in fiber Raman amplifiers (FRAs). A comprehensive large-signal numerical model of FRAs, which incorporates time variation effects, and downstream and upstream propagations of multiple signals, pumps, and amplified spontaneous emission components, is developed and used for the theoretical analysis. The effect of pumping schemes, input signal power, pump power, the length and type of Raman fiber, and the number of added or dropped channels on the dynamics of surviving channel power fluctuations is studied. Three different drop/add cases are considered: (a) L band drop/add, (b) C band drop/add, (c) every other channel drop/add. For all three cases, power transient behaviors in fiber Raman amplifiers counter-pumped by multiple coherent pumps or multiple incoherent pumps are analyzed at the same gain. As an example, we consider a FRA pumped by six coherent pumps or two incoherent pumps. Comparison of power transients in those two FRAs is given. It is shown that power transient behaviors of surviving signal channels are almost the same for a FRA pumped by six coherent pumps or two incoherent pumps. However, a FRA with incoherent pumping suffers from slightly severer power transients than that with multiple coherent pumps.


identifier: Xu, Shijie  (2005) Modeling and parametric analysis of micro thermal actuators.  Masters thesis, Concordia University.

abstract: The greatest promise of micro electro mechanical systems (MEMS) lies in the ability to produce mechanical motion on a small scale. Such devices typically run on low power and are fast, taking advantage of such micro scale phenomena as strong electrostatic forces and rapid thermal responses. MEMS-based sensors and actuators have been widely deployed and commercialized. MEMS technologies also have potential applications in optics, transportation aerospace, robotics, chemical analysis systems, biotechnologies, medical engineering and microscopy using scanned micro probes. Microactuators are useful tools for microsystems development. They produce displacement and useful forces to move, grasp or fine tune components of the Microsystems. Thermal actuators are simple devices with good mechanical and dynamic performances. Since integration requires that the designs of the entire system be performed on the micro chip, a good understanding of the performance of the micro thermal actuators is required. Modeling of thermal actuator is a complex task that requires multi physics formulation. In this thesis, a multi-physics analytical model that can accurately predict the performance of a typical U-shaped micro electro thermal actuator fabricated by MUMPS technology is developed and validated through FEM analysis. Further, experiments are carried out on a benchmark micro thermal actuator. On the basis of this model, the relations between geometries of the thermal actuators and their thermal and mechanical behaviors are calculated and mapped out by simulating them in different geometric conditions. A parametric study that evaluates the performance of the devices with respect to the design geometries is carried out. The results are useful for thermal actuator designers


identifier: Dou, Lixing  (2005) 3D finite difference time domain method for anisotropic materials : theory and application.  Masters thesis, Concordia University.

abstract: A 3-D FDTD method for full anisotropic medium was formulated and examined. Contrary to other methods, this approach is separated into two parts: dielectric properties parts and wave marching parts. Dielectric anisotropic properties are realized through the relationships of electric properties---electric flux versus electric field and magnetic properties---magnetic flux versus magnetic field. EM wave marching is realized through the relationships of magnetic field versus electric flux and electric field versus magnetic flux. For the reason that medium properties are expressed separately, this method can avoid major modifications of core updating equations if the studied medium properties change. This can reduces the time necessary for making new FDTD programs for mediums with other properties. This is the reason that this method can also be extended to dispersive, anisotropic & dispersive mediums. A simplified perfect matched layer (PML) was modified and used as the absorbing boundary condition to match anisotropic medium.


identifier: Ramachandran, Uma Bharathi  (2005) Issues in verification and validation of neural network based approaches for fault-diagnosis in autonomous systems.  Masters thesis, Concordia University.

abstract: Autonomous systems are those that evolve over time, and through learning, can make intelligent decisions when faced with unidentified and unknown situations. Artificial Neural Networks (ANN) has been applied to an increasing number of real-world problems with considerable complexity. Due to their learning abilities, ANN-based systems have been increasingly attracting attention in applications where autonomy is critical and where identification of possible fault scenarios is not exhaustive before hand. We have proposed a methodology in which the learning rules that a trained network has adapted can be extracted and refined using rule extraction and rule refinement techniques, respectively, and then these refined rules are subsequently formally specified and verified against requirements specification using formal methods. The effectiveness of the proposed approach has been demonstrated using a case study of an attitude control subsystem of a satellite


identifier: Gholami, Behnood  (2005) Receding horizon control of uncertain systems.  Masters thesis, Concordia University.

abstract: In the first part of this thesis stability robustness for quasi-infinite Receding Horizon Control (RHC) of an uncertain nonlinear system is investigated. A sufficient condition is developed for stability of a general nonlinear RHC system subject to perturbations. The result is further specialized to linear systems. For this case it is demonstrated that the closed-loop system is stable out side a bounded set containing the desired equilibrium point upon satisfaction of an LMI constraint along with a bounded perturbation assumption. The new result is applied for control of a mobile robot system which demonstrates the validity of the approach. In the second part, RHC of an uncertain nonlinear system is considered where the computational time is not negligible. The existing method proposes a solution to deal with non-zero computation time by predicting the states at the next sampling time, which provides the controller with sufficient time to generate the required input signal. This work extends this previous result by applying neighboring extremal paths theory to improve the performance further through the addition of a correction phase to the algorithm. The proposed method is composed of three steps: state prediction, trajectory generation, and trajectory correction. The new approach is applied for control of a mobile robot system, which demonstrates significant performance improvements over the existing method.


identifier: Hasan, SM Musabbir  (2005) Design of data abstraction structure for MDG-HOL hybrid tool.  Masters thesis, Concordia University.

abstract: We have proposed design and implementation of a data abstraction structure that will result in extension to an existing Hybrid hardware verification tool so that it empowers to handle larger data paths automatically.  Interactive and user-expertise-dependent theorem proving techniques are well suited to handle large and complex data path dominated systems. However, they are complicated and difficult to handle when highly complex real-life designs are considered. On the other hand, automated state-space-exploration based techniques can verify trivial systems automatically, whereas they lack in the ability to verify practical designs due to state space explosion problems. To bring about a solution to the dilemma, hybrid approaches are under study, which widely vary in the tradeoff between the expressiveness of interactive approaches and automation and speed of the exploration based methodologies.  In the thesis we have described the design of an abstract data structure that allows natural numbers as the operands in addition to bit level descriptions. As a case study, we specified and implemented a generic computer processor using the abstract data structure. We implemented a parser that would be used to parse the specification and implementation of the design to be verified.  With the parser, and the data abstraction structure, it would be the perfect launch-pad for the implementation of a powerful and largely automatic tool that should be able to verify most practical hardware designs


identifier: Karuei, Idin  (2005) Multi-layer switching control.  Masters thesis, Concordia University.

title: Multi-layer switching control

abstract: In this thesis, adaptive control of systems using switching techniques is investigated. It is assumed that the plant model belongs to a known finite set of models. It is also assumed that a set of controllers which solve the robust servomechanism problem for the family of plant models and a set of simultaneous stabilizers for certain subsets of plant models are given. It is shown that by using the above set of controllers and simultaneous stabilizers and choosing a proper switching sequence, one can minimize the number of switchings to destabilizing controllers. This can significantly improve the transient response of the system, which is one of the common weak points in most switching control schemes. Simulation results show the effectiveness of the proposed method in improving the transient response.


identifier: Pakmehr, Mehrdad  (2005) Dynamic modelling and nonlinear control of vortex-coupled delta wing systems.  Masters thesis, Concordia University.

abstract: The first part of this thesis proposes a control-oriented vortex-coupled nonlinear retarded state space representation of free-to-roll motion of a delta wing. Linear, nonlinear and neural network based parameter identification methods have been used to approximate the rolling moment coefficient. Various experimental results validate the proposed model. In the second part, fast vortex-coupled delta wing roll dynamics with state delay in is controlled using a robust adaptive output feedback control law. The controller has been tested against modelling uncertainties in rolling moment coefficient. The controller is shown to render the delta wing vortex-coupled roll dynamics globally practically stable. Heuristic design process and parameter selection methods have been proposed for easier implementation of this control algorithm. The results of the numerical simulation demonstrate the applicability of this controller for different initial conditions. The third part proposes a combinatory control strategy combined of a modified state feedback stabilizing controller, as the internal loop, and a robust adaptive sliding tracking controller. The robust adaptive tracking controller utilizes a special gaussian radial basis function network for online estimation of unknown nonlinearity. To show the capability of the proposed combinatory control structure, it has been implemented to the delta wing dynamics to follow a complex reference trajectory. Implementing the proposed combined control structure enhanced the tracking performance in comparison to the controller without internal loop. Adding two more control inputs enhanced the tracking controller performance. The Heuristic design process and parameter selection methods have been proposed for easier implementation of tracking control and combined control structure.


identifier: Pedrami, Reza  (2005) Hybrid modelling and simulation of rigid bodies in contact.  Masters thesis, Concordia University.

abstract: Rigid body systems may undergo numerous types of dynamic interactions including collisions and continuous contact which considerably complicate systematic modelling and simulation of such problems. This thesis introduces a new modelling approach based on a hybrid system formulation to describe the dynamics of interacting rigid body systems. Interaction among physical objects occurs in two different forms: impulsive contact and continuous contact. Characteristics of impulsive and continuous contacts are different. Hence the modelling of each contact type requires the use of different approaches. While the impulse-modelling approach better simulates the impulsive contacts, our findings indicate that continues contact is much more accurately modeled using the sliding manifold method. The proposed hybrid system approach combines the impulse modelling method for collision interactions and the sliding manifold method to model the differential-algebraic equations associated with continuous contact interactions. Appropriate discrete states, events, reset maps, and threshold parameters that yield a hybrid automaton framework to describe interacting rigid body systems are developed. To illustrate the effectiveness of the proposed method a rolling ball simulation for a virtual reality system is presented.


identifier: Raissi Dehkordi, Vahid  (2005) Order reduction of IIR and FIR filters using control methods with applications in DSL networks.  Masters thesis, Concordia University.

abstract: In this thesis, the problem of modeling a Digital Subscriber Line (DSL) network is investigated. Any changes made to the DSL network such as addition or relocation of customers may affect the performance of the overall network. Therefore, it is very useful to have a laboratory model to test the effect of every change made to the network easily. The model can also be used by service providers to test the quality of service before assigning a line to a new customer, reducing the trouble-shooting cost. The modeling consists of extracting the magnitude response of a particular DSL channel, fitting the data to a discrete-time finite dimensional LTI model and reducing its order reasonably. The resultant filter will be a suitable model for laboratory implementations. The magnitude response of the DSL network can be computed numerically using general and small-scale models available for transmission lines. The computation can be generalized to the distributed networks. Digital filter approximation can be accomplished using the conventional methods. A gradient-based method is also proposed in order to generate a FIR filter. The model order reduction is performed using Balanced Realization technique which is applicable to all stable finite dimensional LTI models. It is also accomplished by minimizing either mean-squared error or infinity norm of error. The performance of each method is evaluated using standard test loops. A reasonable range of model order for each test loop is also discussed based on the configuration of each loop, which can be used as a general guide for any wired transmission network.


identifier: Arezina, Olivera  (2005) A multipath traffic engineering scheme with path protection for real-time applications in MPLS VPNs.  Masters thesis, Concordia University.

abstract: A growing number of corporations are considering IP Virtual Private Network (VPNs) for interconnection between different sites. Multiprotocol Label Switching (MPLS) is one of the technologies used in network-based IP VPNs to establish backbone tunnels---label switched paths (LSPs) between an ingress---egress pair of nodes. In order to provide service differentiation, separate LSPs, that carry only real-time VPN traffic, can be deployed. These real-time LSPs can then be routed, based on the strict service level agreement (SLA) requirements that apply to real-time applications. In this thesis we address the following traffic engineering problem: How to route primary and protection real-time LSPs so that the SLA requirements expressed in terms of latency, jitter, bandwidth guarantees, and resilience are met? We formulate a Mixed Integer Linear Programming (MILP) optimization problem that takes into account the SLA requirements in one step---the integrated model. The integrated model is NP-complete and has a large number of variables and constraints.


identifier: Khurana, Ekta  (2005) Fault tolerance within session initiation protocol.  Masters thesis, Concordia University.

abstract: The Session Initiation Protocol is an application layer signaling protocol designed for the session establishment between end users. These SIP sessions are established based on a request-response paradigm between the client and server components of the user agent. Proxy servers may exist within the network, which serve as a bridge between two user agents who are either within different domains or are unregistered and unaware of each others' location. The entities however are not always reliable and may encounter faults. First, this thesis aims to identify the locations within a SIP session where faults can occur and the effect on the system. The current mechanisms used to handle these faults were analyzed and it was determined that the user agents were forced to recover from faults by means of restarting the session. A novel approach was then proposed which detects and recovers from faults dynamically


identifier: Wang, LiXin  (2005) Time inconsistency analysis and correction for MSC-2000 specifications.  Masters thesis, Concordia University.

abstract: Message Sequence Charts (MSC) plays an important role in the software life cycle. It is widely used in the requirements, design, and test phases for different purposes. Therefore, it is crucial to insure the correctness of MSC specifications. For that, one has to validate these MSC specifications as early as possible in the development cycle. An important aspect of MSC-2000 specifications correctness is time consistency, including absolute and relative time constraints. The time consistency of Basic MSCs (bMSCs) and High Level MSCs (HMSCs) has been investigated in the last few years. However, a very little effort and research have been devoted for the purpose of investigation and diagnosis of causes of inconsistencies, and also strategies to correct these inconsistencies. This thesis focuses on the consistency checking of MSCs, analyzes and categorizes the causes of time inconsistencies, and provides solutions to correct time inconsistencies. For bMSCs, we classify partial order, propose solutions to identify inconsistency, and provide four correction policies for the different types of inconsistencies. For HMSCs, we decompose them into different simple paths, provide checking algorithms based on the type of the simple paths, and use different correction strategies for these inconsistent paths. Our approach helps MSC developers to insure the correctness of MSC specifications, thereby improving its quality and also that of the resulting software. A tool, called MSCTICC, implementing our algorithms has been developed and assessed in this thesis.


identifier: Chen, Yu  (2006) Using genetic algorithms to schedule multiprocessor systems under LOGP model.  Masters thesis, Concordia University.

abstract: In recent years, with the wide-spreading usage of computer technologies in various aspects of the modern world, the demand for more powerful computers has outmatched the yet rapid advancement in hardware development. LogP model is a practical model that reflects better the practical behavior of nowaday massively parallel computers.  This thesis is dedicated to the design and evaluation of algorithms for multiprocessor system scheduling under the LogP model. The objective is to obtain a feasible schedule of input task graphs and corresponding LogP model with minimum makespan . Due to the NP-hard nature of the problem, we choose the genetic algorithms (CA) to effectively explore the huge solution space.  The approach consists of two main parts. The communication tasks under the LogP model are scheduled by a genetic algorithm with determined processor assignments. Another CA is used to optimize the processor assignments of computational tasks. The design issues in both CA algorithms are discussed in detail.  The evaluation of both parts of the algorithm over a set of benchmark task graphs shows an overall improvement over previous works within the LogP model.


identifier: Pan, Yu Xin  (2005) Efficient MAC protocols using directional antennas for ad hoc networks.  Masters thesis, Concordia University.

abstract: Use of directional antennas in wireless networks has been widely studied in recent years. Since the Medium Access Control (MAC) protocol of the IEEE 802.11 standard is designed for the use of omnidirectional antennas, it cannot work properly when directional antennas are used. To maximize the system throughput in mobile ad hoc networks, one needs to design new MAC protocols that work well with directional antennas. In this thesis, we propose a new MAC protocol that can efficiently utilize the large throughput offered by directional antennas in ad hoc networks. The proposed MAC protocol makes use of two main modes; (i) omnidirectional mode where one antenna is used for the transmission of users' control frames, and (ii) directional mode where antenna arrays are used for the transmission of data frames. We define two separate channels, one for control information and the second for data transmission. We incorporate a simple routing protocol to deal with the out-of-range problem encountered in practical scenarios. The proposed protocol takes into consideration the effect of interference arising from the side-lobes of different stations. Using a practical ad hoc network model, we present performance comparisons with different MAC protocols (including the IEEE 802.11) where we show the large throughput gains achieved using the proposed MAC protocol


identifier: Cowan, Doris  (2005) Time bright, time clouded : a novella.  Masters thesis, Concordia University.

title: Time bright, time clouded : a novella

abstract: This novella deals with changes in the lives and social expectations of men and women in the last decades of the 20th century. Geraldine Taylor, a young woman born just after the end of World War II, grows up in Toronto. Her widowed mother, Gwen, is outwardly rather Bohemian in style, but her rebellious daughter considers her a retrograde example of female subservience to received ideas. The time of the novella is in two parts; the first sketches Geraldine's childhood and then moves to a more expansive view of her life as a young woman in the year 1966. She is determined to live an unconventional life, including love, work, independence and children, but without legal marriage, which she sees as bondage. The second part of the novella begins twelve years later; Geraldine is now a scholar working on a dissertation about the novels of George Gissing. She has compromised with her earlier ideas and has married. She wants to have children, but her husband, an actor, refuses to consider the idea, protesting that it was never part of his idea of marriage. Ultimately their marriage ends and she becomes pregnant from a brief encounter with an old friend. She has decided that single parenthood is better than any of the other lives open to her. In this way a life that began with perhaps unrealistic hopes settles into a form of qualified happiness.


identifier: Skibsrud, Johanna  (2005) The sentimentalist.  Masters thesis, Concordia University.

title: The sentimentalist

abstract: The Sentimentalist works to combine several interconnecting stories in order to explore the processes of death and dying, of guilt, and of the trauma of War. A central character, Caroline Emerson, is developed through whom---over the course of a summer spent at the family's summer house---the remembered histories of her family, and most importantly her father, are told.  The contrast between the oral story-telling method in which these histories are eventually received collides with Caroline's desire to record and understand her family through her photojournalism project: a more objective, and exclusive lens. It is made apparent to Caroline that her father's story is much more complex and many-layered than she originally supposed.  The majority of the novel is set in the family's summer-house situated in a town which was, in the early part of the twentieth century, relocated when the original was flooded by a hydroelectric dam. The new house borders the lake which flooded the original town and the distinct contrast between the past and the present is always---for the residents of the town---apparent. Caroline's father's experience and memories are seen to be, metaphorically, as buried as the old town.  This thesis uses research and oral accounts of the Vietnam War, and demonstrates the complex nature of family relationships and memory.


identifier: Menon, Amy  (2005) Imagining Hindu identity.  Masters thesis, Concordia University.

title: Imagining Hindu identity

abstract: In a postcolonial world, literature is integral to the formation of identity and it is with this in mind that the thesis seeks to address the formation of Hindu identity through the reading of two novels, The Romantics , by Pankaj Mishra, and The Mystic Masseur, by V.S. Naipaul. The thesis examines how Mishra and Naipaul's novels engage with the history of British colonizers fashioning Hindu identity and how this hegemonic power continues to inflect societal concerns. The interrelated dynamics of power and politics are also explored, with a special emphasis on how religion is co-opted into the secular world and how this poses a problem for the Hindus in the above two novels.


identifier: De la Cruz de Oña, Artorix  (2005) CP phases in the chargino sector of the left right supersymmetric model.  Masters thesis, Concordia University.

abstract: We investigate the chargino sector of the left-right supersymmetric model. We consider the most general mass and mixing parameters, including all CP-violating phase. We present a consistent procedure for the calculation of the analytical expressions for the chargino mass eigenstates and eigenvectors. We then follow with the analysis of the cross section for chargino pair production e+e- {602} c&d5;+i c&d5;-j and its dependence of the CP-violating phases was done. We explore also different possible experimental scenarios and signatures.


identifier: Dam, Steven  (2005) No femmes, queens or flamers! : gay male effeminacy and the culture of shame.  Masters thesis, Concordia University.

abstract: Male homosexuality has long been associated with effeminacy. Yet, despite the long-standing historical association between effeminacy and male homosexuality, little research has examined the monitoring and punishing of effeminacy within the gay male community. This project is devoted to the study of gay male effeminacy and the shame that often accompanies its presence. What is it about effeminacy that continues to haunt the gay male community today? How, and why, is masculinity enforced by so many gay men, and what is at stake in the fight against all things flaming? What is wrong culturally about shaming effeminacy? Looking at personal ads and specifically the phrase 'No femmes, queens or flamers!,' this thesis examines the gender hierarchy within the gay male communitiy that privileges the masculine by subjugating effeminacy. I argue that the gay male community employs a practice of shame and shaming in order to consciously reject, suppress and oppress effeminacy. Integral to this thesis is how a culture of shame fuels the process of inclusion/exclusion by, and among, gay men. This thesis also examines the intersection of race, gender and sexuality, examining how both the gay male and the Asian male bodies have been discursively constructed as effeminate. Overall, this thesis critiques current modes of gay and lesbian politics that strive for normalization, elsewhere known as assimilation, tolerance, or sexual 'minority rights,' particularly with respect of gender.


identifier: Ghandehari, Mahya  (2005) Independent sets in graph products via harmonic analysis.  Masters thesis, Concordia University.

abstract: In this thesis we study the independent sets of Knr , the weak product of n complete graphs on r vertices, which are close to be of maximum size. We review the previously known results. For constant r and arbitrary n, it was known that every such independent set is close to some independent set of maximum size. We prove that this statement holds for arbitrary r and n. The proof involves some techniques from Fourier analysis of Boolean functions on Znr . In fact we show that when most of the 2-norm weight of the Fourier expansion of a Boolean function on Znr is concentrated on the first two levels, then the function can be approximated by a Boolean function that depends only on one coordinate. A stronger analogue of this has been proven by Jean Bourgain for Zn2 . We present an expanded version of his proof in this thesis.


identifier: Guo, Xiao Jing  (2005) A climate-sensitive analysis of lodgepole pine site index in Alberta.  Masters thesis, Concordia University.

abstract: Growth and yield models in forest management are derived from past observations, assuming implicitly that future growth conditions will be similar. Local observations of apparent changes in site index (SI: defined as the top height at 50 years breast height age) of lodgepole pine in Alberta during the 20th century raise serious questions about validity of this assumption. As part of a joint program on climate change in Alberta by Canadian Forest Service and Laval University, this thesis aims at investigating the impacts from climate change on the site index based on a process-based forest growth model, StandLEAP. Data processing techniques, nonlinear regression and time series analysis are conducted to obtain the necessary models. The research involves the calibration of a climate-sensitive site index model. This model is then used to explain Sl variability between 1901 and 2000 for each plot. A significant SI increment of 4 mm/year appears on average. This change is significant over 100 to 200 years, the time period used to check that the projected cut can be sustained by the forest over the long term. Over this time period, stand SI will change from .4 to .8 m, more than half of a site index class. The results suggest that climate is an important factor affecting lodgepole pine productivity in Alberta, and have implications for future forest management under a warmer climate


identifier: Kumar, Nootan  (2005) The relationship between heritage language fluency loss and the cultural value of filial duty : an Indo-Canadian Hindu perspective.  Masters thesis, Concordia University.

abstract: It is common belief that language and culture are inexorably linked (Edwards, 1997), yet the precise nature of this relationship remains elusive. This study investigated one hypothesis about this relationship, that a loss in language signals a loss in culture if language is considered a central value (Smolicz, 1985). This hypothesis was tested by examining whether Hindi represents a central value to the North-Indian culture in Canada and thus predicts its loss or maintenance in this context. The relationship between language and culture was investigated by rating the Hindi (L1) and English (L2) proficiency of 30 first- and second-generation Indo-Canadian Hindi speakers (15 parent-child pairs) and correlating these to their reactions to culturally-charged scenarios in a matched-guise task (featuring English and Hindi versions of the same scenario recorded by the same speaker). The scenarios targeted one aspect of North-Indian culture---the value of filial duty---in two contexts (marriage, career). It was hypothesized that if language loss triggered culture loss, then speakers losing their L1 (second-generation speakers), but not those maintaining it (first-generation speakers), would react to scenarios differently according to language. Findings revealed that a language shift has taken place in the North-Indian community and that the beginnings of a cultural shift in filial duty are underway, which may or may not be mediated by this language shift. Implications of these findings are discussed with respect to heritage language and culture maintenance, the language-culture relationship, the South Asian diaspora, Canada's multiculturalism policy, and other issues including group identity construction


identifier: Salvati, Carla  (2005) The relics of the stigmata of St. Francis of Assisi.  PhD thesis, Concordia University.

abstract: Francis of Assisi was the first saint in the history of Christianity to receive the stigmata. In 1224, while meditating on Mount La Verna the wounds of the Crucified Christ appeared on his hands, feet and side. The subject of this dissertation is the cult of the relics of the stigmata of St. Francis. These include tiny ampoules of blood from the wounds, the habit Francis was wearing when he received the stigmata, the bandage worn over the side wound as well as a sock and shoe worn to protect the wounds on his feet. The hypothesis of this study is that the relics of the stigmata of St. Francis of Assisi do not fit the categories developed to account for the relics of Antiquity and the early Middle Ages; they introduce unique, new kinds of relics to medieval Christianity. The devotional practices and reflections around the relics of the stigmata of St. Francis show that his wounds were treated as the physical embodiment of a mystical experience. The relics of the stigmata were, I argue, relics of the points of contact and union between Francis and Christ. Devotional sources from the 16th and 17th centuries are examined which express the belief that Christ had crafted the wounds in Francis's body, transforming him into a living artifact. The relics were believed to be the only remaining traces of what Christ had crafted with his own hands. This study examines how the relics of the stigmata were infused with the meaning of the physiology, the poetics and the theology of the wounds which bridged the gap between heaven and earth.


identifier: Wang, Chenhuan  (2005) Fault recovery in discrete-event systems using observer-based supervisors.  Masters thesis, Concordia University.

abstract: We solve the supervisory design problem using a state-based approach. It is assumed that design specifications are given for normal, transient and recovery modes in terms of legal (safe) states. The system under supervision is also required to be nonblocking in normal and recovery modes. Following a modular switching approach, we propose supervisory schemes in which separate supervisor modules are designed for normal, transient and recovery modes. We consider failure accommodation in cases where recovery to normal operation is not possible and also recovery in cases in which it is possible to resume normal operation. For each case, we provide two solutions, one in which the recovery supervisor is in the feedback loop when the system is started in its normal mode, and another solution in which the recovery supervisor is engaged only when a fault is detected and isolated. The latter approach is less computationally complex to implement. We investigate supervisor admissibility and nonblocking property of the system under supervision. All of the supervisor modules are observer-based. In our opinion, the use of observer-based supervisors results in a more transparent solution and simplifies the analysis in our switching scheme when one supervisor replaces another in the feedback loop. In this thesis, in the process of our study of fault recovery, we also propose a systematic method for designing observer-based supervisors using normal languages.


identifier: YU, Yong Jun  (2005) Congestion control in networked systems.  Masters thesis, Concordia University.

title: Congestion control in networked systems

abstract: This thesis discusses the centralized and decentralized congestion control strategies in differentiated services of a networked system. First a sensor-decision maker-actuator (3 nodes) network structure is designed and traffic flow is divided into three classes: Premium, Ordinary and Best effort. For each node we design a control strategy based on the dynamic fluid flow model and M/M/1 queuing theory to allocate bandwidth to different class traffic for avoiding congestion. For the whole network, we design control algorithms based on both centralized and decentralized methods. The stability of the closed loop system is analyzed and some comparisons between centralized and decentralized schemes are made. Several examples and simulation results are included to illustrate the design methodology.


identifier: Najjar-Khatirkolaei, Biglar  (2005) Transverse magnetic wave scattering by elliptic chiral cylinder.  Masters thesis, Concordia University.

abstract: The electromagnetic scattering problem of normal incident waves on an elliptic chiral cylinder is considered. The cylinder is assumed to be homogeneous and isotropic and extends infinitely long in the z direction. An exact boundary value solution for the scattering problem of the TM wave by the elliptic chiral cylinder is analyzed and presented. The solution is based on the separation of variable technique in the elliptic cylinder coordinates system, and expressed in terms of Mathieu and modified Mathieu functions. The incident, transmitted and scattered electromagnetic waves are expressed in terms of an infinite series of wave functions. The matrix forms of the expansion coefficients are found by applying the boundary conditions and orthogonality of the Mathieu functions. The expression of the radar cross section (RCS) per unit length or echo width of electromagnetic wave scattering by elliptic chiral cylinder for co- and cross-polarized waves are derived by using the asymptotic expansions for modified Mathieu functions. Validation of the developed formulation and computer program are investigated by considering many limiting cases such as circular dielectric, circular perfect conducting, and circular chiral cylinders, as well as elliptic dielectric and elliptic perfect conducting cylinders. Numerical results of the forward and back scattered echo widths for both co- and cross-polarized waves for various cases are presented and discussed. The numerical results show the co- and cross-polarized bistatic and monostatic echo widths depend on the frequency and incidence angle of the incident wave, constitutive parameters and geometry of the elliptic chiral cylinder. In general, the echo widths decrease by increasing the chirality admittance, and increase by increasing the axes of the elliptic chiral cylinder.


identifier: Cooke, Grayson  (2005) Bio/Techno/Logo : writing and the face in the human/machine relation.  PhD thesis, Concordia University.

abstract: This thesis asks the question of the relation between humanity and technics, and the role of writing in mediating this relation. Since Plato, this relation has been a concern of philosophical thought. More recently, it has been brought to the fore by technoscientific and biotechnological practices, and contextualized in terms of the cyborg, the posthuman, the hybrid. Using a deconstructive methodology, and conducting analyses of filmic, literary, promotional, theatrical and critical texts, this thesis argues that humanity and technics are codetermined and codetermining. The thesis is divided into two parts, each of which follows this argument through different realms. Part One focuses on the concept of 'the writing machine'. Writing, as a tekhne, has often been derided for its supposed status as external to the present, human subject. Through analysis of key texts by Jacques Derrida and Bernard Stiegler amongst others, this thesis demonstrates that writing and thus technics are not external to the human but are rather determinants of the human. In contemporary biotechnological discourse, technics has come to function as a primary metaphor in the understanding of biological and human 'life'. Again however, it is writing that conditions, powers and instantiates this technical rendering of life. Part Two focuses on the concept of 'the face'. The face is one of the most crucial scenes in which the relation between the human and the technical is played out. The face is the representative of the human being. The face implies and implicates the human, it is the seat of communication and language, and in contemporary cosmetic culture, it is the locus of striving for ideals of public appearance. But appearance is far from simple. The fact that faces 'have' an appearance suggests that appearance is a matter of seeming and resemblance, that is, of representation. The human face is always mediated by technical systems and medical cures, it is promised by technics and kept in abeyance by technics, in one and the same movement. Through the face, the human remains always a spectre, there by not being there, mediated by technological becomings and virtual projections.


identifier: Mukherjee, Ritesh  (2005) Secure group communication.  PhD thesis, Concordia University.

title: Secure group communication

abstract: With the advent of digital technologies and widening Internet bandwidth in recent years there has been a marked rise in new multimedia services, including teleconferencing, pay-per-view TV, interactive simulations, software updates and real-time delivery of stock market information. Multicast data distribution has been used in controlled environments to deliver such services. However, the lack of secure, accountable multicast data distribution has prevented its use in general Internet environments. Proposals for multicast security solutions so far are complex and often require trust in intermediate components or are inefficient. A secure multicast protocol suite must provide for data confidentiality, for multicast packet source authentication and for the representation of multicast security policies. In this thesis we present a robust, simple and efficient multicast key management protocol based on proxy encryption, a multicast data source authentication mechanism based on symmetric message authentication codes and a simple multicast policy representation scheme based on XML. The solutions are analyzed and compared to previously published schemes. The results show that the proposed schemes are efficient and scalable when compared to existing schemes.


identifier: Moussa, Mohammad Hazem  (2005) Direction of arrival estimation using maximum likelihood method and the effect of element selection on system performance.  Masters thesis, Concordia University.

abstract: This thesis was performed by first understanding the concept of DoA estimation and realizing its importance and applications. Second, DoA estimation techniques, which are not few and vary in principle and applications, were reviewed in order to find the most suitable technique to use in this thesis. The target is to find a DoA technique that is simple to construct to illustrate the effect of mutual coupling and array antenna element selection on the DoA estimation process, and at the same time, to be a technique from which the obtained results could be generalized to more specific cases rather than one or two cases. The Maximum Likelihood Method was found to be the most suitable DoA technique. Third, the MLM was implemented using both, omni-directional elements and point sources as the array antenna elements. Fourth, NEC2 was introduced, its theoretical and principal of operation were explained. Also mutual coupling between the array elements was introduced as it affects the over all performance of the array structure in DoA estimation. Finally, a NEC2-Matlab interface was implemented to produce Mean Square Error graphs for different scenarios using the MLM and n/2 dipole antennas as the array elements and then n/2 dipole antennas above perfectly conducting ground plane. This change of elements in the array structure produced a significant enhancement in the DoA performance. Another approach that was also tested was changing the spacing between the array elements. This approach, under certain conditions, also showed a significant enhancement in the DoA estimation performance.


identifier: Benguigui, Linda  (2005) Films on art and/or art on film : Jacques Giraldeau's cinematic vision of the 1960s.  Masters thesis, Concordia University.

abstract: Films on art have provided audiences with new ways of apprehending art since the early part of the twentieth century. Yet, the film on art did not remain a strictly didactic tool since there have always been film directors to blur the boundary between a film on art and an art film. Jacques Giraldeau is one of these film directors. This thesis looks at three of Giraldeau's films: La forme des choses, Les fleurs c'est pour Rosemont and Bozarts. The first film is an abstract look at the works shown at the first international sculpture symposium in 1964 in Montreal. It is a deliberate collage of images of the sculptures interspersed with images of the landscape in which they were exposed. The second film is a bleak look at an architectural project started by a group of recent university graduates to revamp an alleyway in an impoverished district of Montreal. The film showcases the residents's disillusionment and frustration with their plight. It provides ground for a discussion on class disenfranchisement. The last film is a survey of the art scene in Québec in the late 1960s. It takes note of the various actors's opinions, such as gallery owners, museum directors, art critics and artists. Coupled with the views of the lay public and their incomprehension of the hermetic art world.


identifier: Sharifi, Hamid  (2005) Collocation methods for the numerical bifurcation analysis of systems of nonlinear partial differential equations.  PhD thesis, Concordia University.

abstract: The study of nonlinear phenomena has been an important endeavor for scientists. Some nonlinear phenomena can be modeled mathematically as nonlinear partial differential equations (PDEs). There are no analytical solutions for most nonlinear PDEs. Therefore, an appropriate numerical method must be used in order to compute an adequate approximate solution. A new class of numerical methods, called Finite Element Collocation Methods with Discontinuous Piecewise Polynomials, has recently been proposed for solving nonlinear elliptic PDE. In this thesis, this method has been generalized for solving nonlinear elliptic PDE systems using an alternative nested dissection solution procedure. Using a modified formulation of the pseudo-arclength continuation method, we have used this method in continuation studies and in the numerical bifurcation analysis of nonlinear PDE systems. In the thesis the method is introduced gradually, starting with the simplest case, linear ODE BVPs, followed by nonlinear ODE BVPs, linear scalar PDEs, nonlinear scalar PDEs, continuation problems in nonlinear scalar PDEs, and, finally, continuation problems for systems of nonlinear PDEs. AUTO has probably been the most widely used continuation software package for ODE problems. The collocation method introduced in this thesis, as well as the numerical method used to solve the resulting systems of nonlinear equations, can be viewed as a generalization to PDEs of the robust and powerful techniques for ODE BVPs that have made AUTO so widely used in computations and as a model for other continuation software projects. As a part of the research toward the construction of an AUTO-like software package for PDE problems, prototype software has been developed for the numerical bifurcation analysis of nonlinear elliptic PDE systems in two-dimensional space (2D). The UML (The Unified Modelling Language) notation is used to present the implementation algorithms and our object-oriented prototype software. We consider several test problems, as well as some practical applications, such as the Bratu-Gelfand problem, the Brusselator system, and the streamfunction-vorticity formulation of the Navier-Stokes equations for a two-dimensional incompressible fluid flow problem. These examples demonstrate the capabilities and the strength of the collocation method with discontinuous elements for solving substantial PDEs continuation problems.


identifier: Bobiy, Mikaela  (2005) Imitatio Christi : the Christic body in performance.  PhD thesis, Concordia University.

abstract: In this paper, I endeavor to make a case for the Christic masochistic performance through an examination of selected works by four contemporary artists. In order to do so, I will conduct an investigation into the meaning of the Christic figure in contemporary times, and more precisely, in visual culture---why appropriate this visual motif and to what ends? What is the audience looking for in the Christic masochistic performance? In approaching these questions, I will examine a number of Christic rituals and iconographic motifs, namely, Eucharistic practice, as it is played out in a number of performances by Chris Burden, Marina Abramovic, Orlan and Bob Flanagan. Also included, is an investigation into the uses of the relic, the icon, the arma Christi (etc.), as they are integral to the Christic masochistic performance. This will be followed by a brief inventory of various devotional practices, from imitatio Christi, to acts of self-mortification and asceticism, which form the basis for many of these performances. In approaching these issues, this paper will be arguing for an ambivalent Christic figure, one that assumes the roles of mother and father, and incorporates what has been construed as both ''male'' and ''female'' devotional practices. I will also look at how these practices, and the Christic figure in general, correspond to the established model of masochistic performance. In short, this paper examines what I consider to be a lack, or lacunae, in performance art studies, namely, the reluctance to speak about the Christic body in performance. It is my contention that the centralization of the Christic figure, and its rituals in contemporary art, is paramount, and can be related to what Luc Ferry has recently identified as the divinization of the human, thereby further opening up the discussion regarding the meaning of the Christic subject in visual culture and in society in general.


identifier: Calogeropoulos, Catherine  (2005) Refining, testing and evaluating spatially explicit models for wind dispersed plants.  PhD thesis, Concordia University.

abstract: Dispersal is the process by which plants expand their range and explore new habitats. When local habitats become inhospitable, dispersal ability becomes the key mechanism allowing species to evade extinction. Despite the efforts in obtaining empirical dispersal curves and developing sophisticated spatial models, the main issue that remains unresolved is that of scale. Although predictions at the local scale are better than those aiming to describe dispersal at greater distances, they remain too unrealistic to be used in subsequent models that govern growth, mortality and resource exploitation. My first chapter aims to improve predictions at the local scale by refining the parameters of a spatially explicit model. I determined the effect of substituting basal area for cone production as a proxy for seed output. The results showed that the r2 from the regression of predicted versus observed densities increased by 5% for seeds and 15% for seedling simulations. Next, I determined the effects of allowing the horizontal wind speeds to vary. The results showed that correlations of observed vs. predicted recruitment are a function of the assumed meteorological conditions used to drive them. My second chapter tested the ability of inverse modeling to predict recruitment both at the stand level and beyond. Using the maternally derived DNA from seed coats of the North American tree species Pinus strobus, I compared the most common approach (inverse modeling) with the newer but far more time-consuming method of using microsatellite markers. I showed that inverse modeling grossly underestimates seed dispersal potential in this species and thus caution against its continued use. With the aim to improve spatial models, this thesis would not be complete without an examination of the role of wind on seed abscission---the precursor to dispersal. Previous attempts to link the probability of abscission with meteorological phenomena were set within averaging times that exceeded the time frame of seed abscission (<1 second) by at least 15 times. Using 1-minute averaging times, I showed that seed release, for the wind dispersed tropical tree Ceiba aesculifolia, is proportional to the square of the horizontal wind speeds. Furthermore, the data showed that this relationship is highly time sensitive where a correlation is no longer evident at averaging times exceeding 25-minute intervals. This thesis is concluded by showing that updrafts are much more effective at causing seed release than all other wind directions (i.e. downdrafts and horizontal). What it can not show, however, is the frequency of upward abscission events within a forest environment and how these results can be implemented within spatially explicit models that predict the dispersal potential of seeds traveling horizontally or vertically. Indeed, this can be addressed in future work.


identifier: Dufour, Marianne Bérubé  (2005) Quantification of air leaks through the building envelope using infrared thermography.  Masters thesis, Concordia University.

abstract: A laboratory experimental procedure has been developed for the acquisition of thermograms of surface temperature distributions due to air leaks through the building envelope. Air leaks through a sample single layer building envelope assembly with a crack of variable width have been reproduced in an environmental chamber inside which conditions met during building envelope thermography surveys were reproduced. The reference emitter technique has been used for the improvement of the accuracy of the absolute temperature measurements with infrared thermography. A qualitative study of the thermograms obtained is presented highlighting the differences between temperature patterns due air leaks through the assembly under different conditions. Also, quantitative relationships between assembly surface temperature distributions due to air leaks and crack dimensions are established. Two methods are presented and discussed, the first based on image segmentation technique and the second on tomography, for building envelope cracks sizing using infrared thermography.


identifier: Tian, Nong  (2005) Realization of current mode filters using the concepts of transposed networks and nullors.  Masters thesis, Concordia University.

abstract: Current-mode circuits have become very important in the design of high-speed analog integrated circuits that are highly linear and possess a wide dynamic-range. Efficient design of current-mode (CM) filters is still a major challenge to the designer. Considerable researcher efforts have been made for the realization of current-mode filters from the existing voltage-mode (VM) filters. In 1971, Bhattacharyya and Swamy introduced the principle of network transposition, which has led to a very efficient way to convert a voltage-mode circuit to a current-mode circuit with the same transfer function, and with a one-to-one correspondence between the elements of the two circuits. In this thesis, using the concepts of the transposed networks, and the nullator-norator representation for active devices, it is shown that a voltage-mode filter implemented using an operational amplifier (OA) can be very easily converted to a current-mode filter using the same OA, when the OA is configured as a three-terminal element. The effects of the finite gain bandwidth of the OA on the CM and VM filters are studied. If the OA is configured as a four-terminal device in a voltage-mode filter, it is shown that the corresponding current-mode filter can be implemented using an operational floating amplifier (OFA), which is a practical realization of a four-terminal nullor. The theoretical analysis about the proposed method is verified by using simulation results as well as by practical experiment using discrete components, such as resistors, capacitors and LM741 (OA) devices. Finally, an OFA is designed and laid out using 0.18 om CMOS technology to validate the design of a current-mode filter using the OFA as the four-terminal nullor. Simulations as well as the experimental results show very good agreement with the theoretical analysis.


identifier: Rahman, Farhana  (2005) Passive earth pressure on embedded plate anchors in sand.  Masters thesis, Concordia University.

abstract: Earth pressure on anchor plates is considered a viable resisting force for the design of underground structures. The theories available in the literature overestimate the earth pressure on these anchors, leading to unsafe design and perhaps loss of structures and lives.  The present investigation is directed to study the passive earth pressure distribution as function of the stress history of the soil represented in terms of the overconsolidation ratio and the depth of embedment. The objective of this study is to validate the theories of Hanna and Khoury (2005) and to examine the case of earth pressures acting on anchor plate, which believed to receive little attention in the literature. Numerical models were developed using the finite element technique and the constitutive laws of Mohr-Coulomb for cases of retaining walls and embedded anchor plate in sand.  The produced results reconfirmed the theories developed by Hanna and Khoury (2005) for the cases of walls retaining overconsolidated sand and walls retaining overconsolidated backfill overlying natural deposit


identifier: Xiao, Jun  (2005) Analysis of product-separable 2-D IIR discrete filters with feedbacks for variable characteristics.  Masters thesis, Concordia University.

abstract: In order to design 2-D digital systems with variable characteristics, product-separable IIR filters with feedbacks in each dimension are studied. The stability and response of such systems with different situations are analyzed and discussed. Belonging to one of the methods of generation of VSHP in z-domain, product-separable IIR filters with dimensional feedbacks offer variable characteristics. The variable feedback gain in one-dimension is analyzed with all the other coefficients based on Schussler's Theorem. The stable conditions for the feedback in terms of other coefficients are obtained and hence a stable range of the feedback gain is determined. Within the stable range of feedback in each dimension, different filters' 2-D frequency responses have been studied and observed with different situations. Significant variable characteristics and different 2-D symmetries are shown with stable responses. Relations between the feedback and response are discussed. Furthermore, to extend this analysis to higher order systems, a computerized analysis method and algorithm is proposed and implemented. This approximation method can work with any order of IIR or FIR filters and has low computation complexity. More complex systems with variable characteristics can be composed and examples of Image Processing with these filters are simulated as space-domain applications.


identifier: Kalavenkataraman, Sudeesh  (2005) Wind loading on rainscreen walls : a wind tunnel investigation.  Masters thesis, Concordia University.

abstract: Wind loading is important but difficult to evaluate in the design of rainscreen walls. Full-scale measurements concerning pressure equalization of rainscreen facades have been carried out at the Technical University of Eindhoven (TUE) in the Netherlands. The measurements of the exterior and the cavity pressures for limited leakage-area and venting-area configurations have been taken over a period of more than a year on a central panel of the main TUE building and the field data has been analyzed in both time and frequency domains. The present wind tunnel study attempts to simulate these full-scale measurements in order to establish the techniques and parameters required for a detailed investigation of the rainscreen wall behaviour under the influence of the wind. The study presents the results of the wind tunnel experiments, compares them with the full-scale data and discusses their similarity after introducing appropriate corrections. Both mean and fluctuating pressures are evaluated for central and edge rainscreen wall panels exposed to a variety of wind directions.


identifier: Badawieh, Ammar  (2005) Heavy metal removal from petroleum oily sludge using lemon scented geraniums.  Masters thesis, Concordia University.

abstract: One major problem facing the petroleum industry today is to find an acceptable approach to manage oily sludge generated during the petroleum processes. Scented Geraniums (Pelargonium sp. 'Frensham') have demonstrated a great ability to survive rough conditions (poor soil, high/low temperatures, high heavy metals concentrations, low water content, etc.). Subsequently, an investigation using Scented Geraniums was performed in a series of pots containing oily sludge where heavy metal concentrations were artificially increased up to 2000 ppm. In a period of 50 days, plants were grown in two systems: (1) oily sludge-soil, and (2) oily sludge-soil-compost. The study took place in greenhouse facilities under the following parameters: 12 h light, 28--34/20{493}C temperature day/night, and around 30 to 40% relative humidity. During the investigation period, soil was sampled periodically and subjected to physico-chemical analyses. The results showed differences related to the sludge system and type of heavy metal.


identifier: Yang, Lu  (2005) Handling feature interactions in the SIP servlet context.  Masters thesis, Concordia University.

abstract: Session Initiation Protocol (SIP) and Servlet technology introduce new ways of delivering telephony services over IP networks. The richness and flexibility of these new protocols make it faster and easier for service providers to develop and deploy new services. This flexibility, however, is offset by the challenge of managing the feature interaction problem, which can prove to be quite severe. This thesis proposes a modified SIP Servlet architecture and introduces a logical entity, the Feature Interaction Handler (FIH), to address the feature interaction problem for telephony services. The approach addresses offline and online feature interaction detection, the former occurring when the user registers to a feature and the latter occurring during feature runtime execution. For offline feature interaction detection, a behaviour mapping approach is introduced to reduce the interaction matrix table. For online feature interaction detection, two mechanisms are proposed---'forward detection' and 'backward detection'. Forward detection extends the originating side user profile when sending the message, such that the terminating side can use it for detection. In contrast, backward detection correlates the SIP session 'request' message with the 'response' message belonging to the same session in order to determine if the resulting service behaviour is acceptable. To validate the new feature interaction detection approach, an offline feature interaction detection tool and online feature interaction detection unit FIH have been implemented. The feature interaction benchmark is applied on both the tool and the FIH, the result proves to be successful. The feature interaction detection approach proposed in this thesis proves to be a viable solution in the context of SIP servlet service environment.


identifier: Tremblay-Simard, Andréanne  (2005) Real option value of regional integration for foreign investors.  Masters thesis, Concordia University.

abstract: We study the relationship between regional integration and foreign direct investment (FDI) flows. We suggest that FDI flows are attracted by a host country's intrinsic real option value to join a larger economic union. The option grants the investing firms the possibility to secure a strategic advantage in servicing the enlarged market, should the host country join the economic union. The strategic advantage comes from market preemption and learning effects. We develop a model for the FDI flows into countries that wish to join an economic union and we empirically test the model by studying the FDI flows into the countries that were candidates to the successive enlargements of the European Union. We find that the FDI flows do not behave accordingly to our real options model.


identifier: Gong, Jianmin  (2005) Correlation and capacity analyses of multi-input multi-outpoint communications systems.  PhD thesis, Concordia University.

abstract: In this thesis, several factors which affect the channel capacity of multi-input multi-output communication systems have been studied under the assumption of a narrow-band Rayleigh fading channel. The first factor is the capacity's diversity property. The previously known result is verified that the outage (a certain probability is out) capacity of N1 transmit antennas and N 2 receive antennas systems is higher than that of N 2 transmit antennas and N1 receive antennas when they have the same signal-to-noise ratio and N 1 < N2 in the independent and identically distributed Rayleigh fading channel. The second is the point of diminishing returns in the increase of capacity with the increase of the number of antennas. With the Monte Carlo simulation, it is found that six receive antennas reach the point of capacity diminishing returns for a small number of transmit antennas and four transmit antennas reach the point for a small number of receive antennas. The third is the correlation between different paths in a correlated narrow-band Rayleigh fading channel. It is shown that the receive antenna polarization matrix must be orthogonal with the incident source polarization matrix to achieve zero correlation. An abstract spherical model is introduced so that the effect of antenna pattern on the correlation and thus the capacity can be studied. It is found that the broadside linear array with the half-wave square patch microstrip antennas has higher outage capacity than that with half-wave dipole antennas in most orientations. This phenomenon still exists when both the transmit array and the receive array are square and rectangular arrays, respectively. Furthermore, a correlation model based on a statistical Student's t-distribution of angle-of-arrival is developed in order to investigate the effect of antenna pattern in a more realistic environment. It was found that the vertical linear array with half-wave patch microstrip elements has higher capacity than that with half-wave dipole elements in the orientation of the antenna visible region. However, for the horizontal linear array, the microstrip elements have different variation of capacity versus orientation with the dipole elements due to the effect of antenna pattern. The cross linear array illustrates higher capacity than the vertical and horizontal linear arrays, indicating that this array is closer to the condition of zero correlation.


identifier: Harvey, Mark C  (2005) Effects of social status and food availability on predator avoidance behaviour in young-of-the-year rainbow trout, oncorhynchus mykiss.  Masters thesis, Concordia University.

abstract: Prey animals are often faced with a Hobson's choice: risk starvation or risk predation. Individuals capable of optimizing this trade-off through the use of context specific predator avoidance behaviour should be at a selective advantage. Food availability and social status have been shown to exert a strong influence on this trade-off, however, it remains unknown if these factors interact (i.e., do dominants and subordinates vary their behavioural decisions based on food availability). The purpose of this study was to examine the effects of food availability and social status, as well as their interaction, on the individual behaviour by young-of-the-year rainbow trout (Oncorhynchus mykiss) in response to perceived predation threats. Pairs of dominants and subordinates were assigned to either low, intermediate or high food availability treatments and exposed to either conspecific alarm cue (predation threat) or distilled water (no threat). The results suggest that an individual's response to a perceived predation threat is indeed dependent upon both social status and food availability.


identifier: Duanmu, Chunjiang  (2005) New motion estimation techniques and their SIMD implementations for video coding.  PhD thesis, Concordia University.

abstract: Compression of video signals is of great importance to modern multi-media systems. In order to achieve efficient data compression, block motion estimation is generally employed to remove temporal redundancies inherent in video signals and thus, it is a crucial component of international video coding standards. This thesis aims at developing techniques to reduce the computational complexity of a given block motion estimation algorithm without sacrificing its accuracy, to utilize the single instruction multiple data (SIMD) technique to accelerate a block motion estimation process, and to develop a new fast block motion estimation algorithm suitable for implementation using SIMD architecture. A method to detect blocks that are stationary between successive frames, is proposed. In this method, when a block is judged as stationary, the search process for such a block is skipped in the block motion estimation process. The statistical characteristics of the video sequence are utilized in deciding as to which blocks are stationary. Simulation studies are carried out showing that this method reduces the computational complexity of the various block motion estimation algorithms without sacrificing the accuracy of the original algorithm. A vector-based fast block motion estimation algorithm, suitable for implementation on an SIMD architecture, is proposed. This algorithm maintains the accuracy and coding efficiency of the full-search algorithm, but the complexity is only a very small fraction of that of the full-search algorithm. It is also shown that by implementing the proposed algorithm on an SIMD architecture, the execution time of the algorithm can be further reduced by about 74%. The concept of an eight-bit partial sum is introduced so as to take advantage of the byte-type data parallelism in the existing SIMD architectures. A method of employing these partial sums to speedup a given block motion estimation process is proposed. The notion of the eight-bit partial sums is extended to the four-level case and it is shown that there are fifteen possible methods of utilizing these multi-level partial sums to accelerate block motion estimation algorithms. It is shown that any of these fifteen methods can accelerate a given block motion estimation algorithm without any loss of accuracy. The full-search algorithm is used to determine as to which one of these fifteen methods would provide the lowest computational complexity in order for it to be chosen to accelerate the various motion estimation algorithms. Simulation studies have been conducted and the results show that the proposed scheme is capable of providing a substantial speedup for the various existing motion estimation algorithms without any loss of accuracy.


identifier: Lapalme, François-Xavier  (2005) FPGA implementation of video noise estimation for real-time processing.  Masters thesis, Concordia University.

abstract: Digital video processing algorithms are computationally intensive and their performance worsens dramatically as image resolution and pixel data size grow larger. Effective techniques are required to contend with this shortcoming in performance. One solution is to make use of a fast-prototyping, flexible and reprogrammable Field Programmable Gate Array (FPGA) technology. This thesis proposes an FPGA implementation of a video noise estimation algorithm capable of real-time processing. The objectives of this thesis consist of adapting a computationally demanding noise estimation algorithm to a synthesizable VHDL design and achieving real-time processing performance. Hardware feasibility is determined through a study of the mathematical operations used in the estimation process. The proposed architecture provides a satisfactory compromise between area and processing speed. Furthermore, parameterization of the architecture allows additional flexibility with the scaling of features, such as filter size, to operate on 3 x 3 or 5 x 5 blocks of pixels


identifier: Ghotbi, Mohsen  (2005) Multistage linear multiuser receivers : large-system design and analysis.  PhD thesis, Concordia University.

abstract: This thesis introduces an analytical method for large-system design and analysis of multistage linear multiuser (MLMU) receivers for direct-sequence (DS-) code division multiple access (CDMA) systems. The figure of merit to evaluate performance is the signal to interference plus noise ratio (SINR) that is calculated for a case where the number of active users and the processing gain tend towards infinity, while their ratio remains finite. The large-system performance will be a function of the number of the interference cancellation stages, the moments of the eigenvalues of the covariance matrix, the system load and the SNR. Compared to other recently-proposed methods, our proposed method offers a more efficient approach to finding the large-system performance by introducing a new expression for the covariance matrix of the interference term. A simplified multistage scheme to estimate the multipath channel gains is also introduced. It will be shown that by applying this new method for data detection and channel estimation, the performance of the MLMU receiver will converge to that of the minimum mean-squared error (MMSE) receiver.


identifier: Habibi, Ali  (2005) A framework for system level verification : the SystemC Case.  PhD thesis, Concordia University.

abstract: Recent advances in hardware design has enabled integration of a complete yet complex systems on a single chip (called System-on-a-Chip: SoC). It is conceivable that the role of traditional Register Transfer level (RTL) languages will diminish to an extent akin to assembly level languages in software design. Therefore, new design languages or so-called System Level Languages (SLL) have emerged. Verification techniques for SOC designs also need to change with this trend. Combining classical verification techniques, such as simulation, with several other formal techniques, into a single approach has been gaining attention in SoC verification. Classical simulation based verification techniques when used with SystemC face several problems related to the object-oriented aspect of SystemClibrary and due to the complexity of its simulation environment. In this talk, we present our proposed methodology to verify SoC designs modeled in SystemC. To this end, we introduce a hybrid approach combining static code analysis, model checking and assertion based verification. We also propose to augment the approach by a test generation module in order to improve the coverage metrics in comparison to the classical simulation approach (mainly based on random test generation)


identifier: Cavalli, Ariane  (2005) Construction des identités raciales, ethniques et culturelles chez des métis montréalais.  Masters thesis, Concordia University.

abstract: Ce mémoire étudie la construction des identités raciales, ethniques et culturelles (ethnoculturelles) de 14 métis noirs/blancs vivant à Montréal, à travers des entrevues semi dirigées. Bien que les approches contemporaines ne posent plus la mixité comme problématique car elle caractérise toute identité, les métis révèlent qu'ils sont 'minorisés' par les Blancs et parfois aussi exclus par les Noirs. Afin d'analyser les entrevues, nous tenons compte de l'influence du contexte, c'est-à-dire de l'état des catégories ethnoculturelles et de leurs statuts respectifs, mais aussi du parcours individuel des métis. Nous concluons que les métis interrogés supportent mal d'être réduits à l'une ou l'autre de leurs origines ethnoculturelles ou d'être considérés comme possédant la moitié de chacune. II semble donc que les identités décloisonnées posent encore problème à Montréal. Comme les participants se considèrent à la fois québécois blancs 'de souche, à 100%' et à la fois noirs---au même titre que les non-métis, ils développent des stratégies identitaires afin de réduire l'écart entre les identités qu'ils se décrivent et celles qui leur sont assignées par les autres. La principale consiste à mettre l'emphase sur une de leurs identités, celle qui correspond le mieux à la situation d'interaction dans laquelle ils se trouvent et de s'identifier uniquement à travers elle à ce moment là. Malgré le fait que leurs stratégies ne fonctionnent que partiellement et qu'ils conservent un sentiment de marginalité, ils considèrent maintenant que leur double héritage culturel est un avantage et sont fiers de l'ouverture d'esprit qu'ils ont développé grâce à lui.


identifier: Yang, Feng  (2005) On the estimation of center of gravity height of arbitrarily loaded articulated freight vehicle.  Masters thesis, Concordia University.

abstract: The accurate prediction of an impending rollover threat of a heavy vehicle forms the essential basis for developing a rollover prevention system. The vehicle roll stability and the rollover predictors are most significantly related to the center of gravity height of the trailer sprung mass, which tends to vary considerably. The developments in the rollover warning devices have been mostly limited due to extreme complexities associated with the onsite measurement of the center of gravity height of an arbitrarily loaded vehicle. In this study, the system identification techniques are applied to obtain an estimate of the c.g. (Center of Gravity) height on the basis of the measured response under a controlled directional maneuver. A simulation model of a five-axle tractor-semitrailer is analyzed in the TruckSim environment to identify the desirable response measure, which is most sensitive to variation in the c.g. height, and the test maneuver for deriving the desired response. A 10 D.O.F. (degree-of-freedom) analytical model of the vehicle is developed and linearized to derive the analytical transfer function relating the steer angle to the desired semitrailer sprung mass roll angle response. A model reduction technique is further applied to obtain a reduced-order analytical transfer function to facilitate its implementation.