identifier: El Farra, Linda   A GIS BASED MODELLING APPROACH TO ASSESS LAKE EUTROPHICATION.  UNSPECIFIED thesis, Concordia University.

type: Thesis PeerReviewed

abstract:
Large proportion of the world’s readily available water supply is at risk due to the rapidly increasing populations of certain types of harmful algae. During the photosynthesis, species like blue-green algae and cyanobacteria consume nutrients and produce toxins that have potential adverse effects to humans and animals.
	This thesis focuses on developing a GIS-based statistical approach to explore the water quality parameters facilitating the algae bloom, and to geographically map the extent and spread of these parameters to enable tracking and prediction of potential algae outbreaks.
	The relationship between Chlorophyll-a, which represents the concentration of algae biomass, and the water quality parameters such as depth, phosphorus, nitrogen, alkalinity, suspended solids, pH, temperature, electrical conductivity, dissolved oxygen and secchi depth is analyzed though correlation matrix then by utilizing modeling techniques including multiple linear, nonlinear regression, neural network and data mining prediction models are developed to quantify the contribution from essential water quality parameters to eutrophication.
	The developed GIS and statistical analysis approaches have been applied to the Lake Champlain. The performance for the developed statistical, neural network and data mining chlorophyll-a models has been examined through the comparison with the observed field data and through statistical error analysis. Two new techniques have been examined in this thesis study. First, data mining has helped to reveal the nonlinear behavior of algae growth in some parts of the case study area. Second, the GIS spatial analysis is employed to visualize the spread and extent of the water quality parameters and the algae chlorophyll-a, which graphically present the location-based impact of eutrophication on important lake water resources. For example, the analysis of the GIS-based impact maps suggests that the algae is affecting the Vermont section of Lake Champlain mainly the Northern and Southern section. The developed models suggest that algae production is affected by nutrients particularly phosphorus. When phosphorus is encountered at low to mild concentrations, the nutrient is linearly affecting algae production, however, at extreme concentrations of the nutrient the relationship between nutrient and algae production become nonlinear. The developed GIS model along with the statistical analysis applied on lake Champlain suggest that Extreme levels of Nitrogen in north and Chloride in the South caused deviations in the models prediction accuracy.


identifier: Kondratenko, Yuliya  (2015) A Syntactic Analysis of Predicate Case Assignment in Russian Copular and Copula-like Clauses.  Masters thesis, Concordia University.

type: Thesis NonPeerReviewed

abstract: This thesis is about Case marking in predicational NPs and APs in Russian, meaning NPs and APs that occur after copular be and copula-like verbs. In the course of this thesis I explore the nature of copular be itself. I argue that copular be in Russian is not ambiguous between a func-tional and lexical category as shown in earlier proposals.  My assumption is that copular be is always a lexical verb with different selectional properties and never a functional head. Conse-quently, the different Case markings on predicational XPs as well as the asymmetry between NPs and APs, found in Russian, stem from these verbal selectional properties as well as Case assigning mechanism and the exact position of the predicational XP within the structure. Thus, there are two structures that I propose for copulative clauses and for clauses with copula-like verbs, one in which the lexical verb selects a PredP (Small Clause) as a complement, and one in which the lexical verb selects a NP as a complement. All the data presented in my thesis can be accounted for by these two structures.


identifier: Hoang, Minh Duc  (2015) Procedure for making flat thermoplastic composite plates by Automated Fiber Placement and their mechanical properties.  Masters thesis, Concordia University.

abstract:
Automated Fiber Placement (AFP) is one of the new manufacturing processes for composites that has many advantages such as fast rate of material deposition, repeatability, and reduction of material waste. Thermoplastic composites compared with thermoset composites show a lot of advantages such as higher impact resistance, recyclability etc. and they are very suitable for primary structures of an aircraft. However, manufacturing of thermoplastic composites requires more efforts because of the very high viscosity of thermoplastic resin.
This study proposed a manufacturing procedure to make flat thermoplastic laminates with different layup sequences by using a heated mandrel during layup process with AFP. It is shown that using a mandrel heated to a temperature higher than glass transition can make flat laminates. Processing parameters which consist of hot gas temperature, compaction force, layup speed, mandrel temperature, were found for different laminates. Moreover, repass after material deposition helps to reduce void content inside the laminates.
The obtained flat laminates show the crystallized thermoplastic resin. The high degree of crystallinity is recommended to have good mechanical properties. Tensile, compression and in-plane shear tests were carried out to determine mechanical properties of the laminates made by AFP. Results are compared with those made by autoclave. Test results show that laminates made by AFP have higher tensile modulus, higher compression modulus, similar tensile strength, and almost equal of shear modulus. However, a reduction in compression strength is observed.


identifier: Abouhamad, Mona  (2014) An Integrated Risk-Based Asset Management Framework for Subway Systems.  PhD thesis, Concordia University.

abstract:
Subway systems play a vital role connecting thousands of people to different destinations on a daily basis. The Canadian infrastructure report card recommended encouraging infrastructure owners to establish asset-management plans based on rates of deterioration and community service levels. Moreover, the 2013 report card for America’s infrastructure assigned a grade D to transit systems indicating they are in a poor condition with strong risk of failure. A possible solution proposed by the 2013 report card is adopting a comprehensive asset management system to maximize investments in light of the fund scarcity dilemma.
The main objective of this research is to develop a risk-based asset management framework for subway networks. The framework works along three interrelated sub-models followed by two main models. A generic subway hierarchy is proposed and risk is assessed using three sub-models; probability of failure, consequences of failure and criticality index. Probability of failure is predicted for different structural elements using inspection reports and Weibull reliability function. Consequences of failure are assessed based on seven criteria along financial, social, and, operational perspectives. A criticality index is introduced to the classical risk equation to assess the functional importance of a station in its location using seven attributes along three main criteria. The Fuzzy Analytical Network Process is employed to analyze experts’ feedback used in the consequences of failure and criticality sub-models. This insures incorporating interdependency between criteria and fuzziness of the analysis. The three sub-models are used as inputs in a fuzzy inference engine to compute the predicted risk index. A set of thirty rules derived from experts through interviews and questionnaires is used to shape the relation between the fuzzy output and input variables. Finally, the second model is developed for a risk-based budget allocation model. The model utilizes the risk index components as objective functions. Decision variables are identified as five generic rehabilitation actions along their cost, time, and percentage improvement. The model provides the recommended rehabilitation action in light of the network total risk index and the available budget per time span.
This is the first risk assessment framework proposed in the subway networks domain. Using a network analysis approach, the elements of a risk index are analyzed and aggregated from elements to lines and segments levels. The model revealed probability of failure to be the main driver of a risk index followed by criticality index and last, consequences of failure. Within the expected consequences of failure, social impacts had the highest impact (38%) based on experts’ feedback. The criticality index sub-model revealed station location to be the most important criteria (35%) followed by station nature of use (33%) and finally, station characteristics (32%). A segment of six stations from Montreal subway network is analyzed. The assessment indicates two stations with high risk indices showing the necessity of an intervention action. The budget allocation model prioritizes stations for rehabilitation according to the decision maker’s risk appetite, assumed at 0.6. The revised risk index for STA 4 dropped from 0.821 to 0.521 and the overall segment index dropped to zero.
This research presents a basis for evaluating subway infrastructure on a structural and functional basis. It assists authorities to derive an informed rehabilitation decision using a generic and consistent framework. The heuristic decision making process followed by authorities is translated into a detailed framework that can be easily implemented and updated. The presented outline can be equally used for segments or the entire network.


identifier: Rashwan, Abderahman  (2015) Automated Quality Assurance of Non-Functional Requirements for Testability.  Masters thesis, Concordia University.

abstract:
A Software Requirements Specification (SRS) document contains all the requirements to describe a software system to be developed. These requirements are typically separated into Functional Requirements (FRs), which describe the features of the system under development and Non-Functional Requirements (NFRs), which include quality attributes and design constraints, among others. NFRs can have a significant impact on the time of a system’s development process and its total cost, as they frequently describe cross-cutting concerns. NFRs that are not testable are typically ignored in system development, as there is no way to verify them. Thus, NFRs must be checked for testability. However, for natural language requirements, this so far had to be done manually, which is time-consuming and therefore costly.
In order to improve software development support, we propose a semantic quality assurance method that automatically detects non-testable NFRs in natural language specifications. Our work contains four significant contributions towards this goal: (1) building a generic ontology which represents the main concepts in requirements statements and their relations; (2) Based on this generic ontology, two corpora are developed: The first one is a new gold standard corpus containing annotations for different NFR types. The second one is for requirements thematic roles and testability; (3) A Support Vector Machine (SVM) classifier to automatically categorize requirements sentences into the different ontology classes is introduced; (4) Finally, a rule-based text mining system is used to analyze requirement thematic roles and to flag non-testable NFRs. Based on the SRS corpus, our results demonstrate that the proposed approach is feasible and effective, with an F-measure of 80% for non-testability detection.


identifier: Harrafi Saveh, Shahab  (2015) Finite Automata Algorithms in Map-Reduce.  Masters thesis, Concordia University.

abstract: In this thesis the intersection of several large nondeterministic finite automata (NFA's) as well as minimization of a large deterministic finite automaton (DFA) in map-reduce are studied. We have derived a lower bound on replication rate for computing NFA intersections and provided three concrete algorithms for the problem. Our investigation of the replication rate for each of all three algorithms shows where each algorithm could be applied through detailed experiments on large datasets of finite automata. Denoting n the number of states in DFA A, we propose an algorithm to minimize A in n map-reduce rounds in the worst-case. Our experiments, however, indicate that the number of rounds, in practice, is much smaller than n for all DFA's we examined. In other words, this algorithm converges in d iterations by computing the equivalence classes of each state, where d is the diameter of the input DFA.


identifier: Gabriels, Jane de Lacy  (2015) Choreographies of Community: Familias and its impact in the South Bronx.  PhD thesis, Concordia University.

abstract:
This thesis documents the creation, performance, and reception of Familias, a performance project created in 1994-95 by visual artist Pepón Osorio and choreographer Merián Soto, both in and out of its generative South Bronx context. This strategic close reading explores and presents Familias as an exemplar and richly instructive instance of socially engaged, community-based art making.

By exploring Familias through multiple points of access – how it dances, speaks, listens and is understood / misunderstood -- this thesis reveals other narratives and paradigms for thinking about the work and its participants, and by extension, further engages with the creative process and production possibilities in the South Bronx. Reviewing Familias further with a curatorial perspective reveals opportunities that could strengthen other current art and community projects. In other words, by thinking about how Familias activates, generates, and replenishes itself in its creative process, this thesis also helps reconfigure how we can think about other possibilities in the borough.

Chapter breakdown:
“Bronx Renaissance” examines structural underpinnings of long-term economic depression in the borough and offers multivalent arguments for change.

“Familias and the South Bronx” offers further historical background that situates Familias locally, and provides insights into the artistic visions and curatorial work of its lead artists.

“Pepatián and the South Bronx” offers insights into my own practice, and how my experiences and creative grappling with the making of Familias, together with my sustained participation and leadership of alternative art making circuits in the South Bronx, led to the creation of a performance piece: How I Became a Boogie-Down Rican.

“Familias” provides four distinct perspectives into the work with interludes to further underscore the impact of performing arts and organizations in the borough. This writing approach with performance and curatorial work as research-site offers material far beyond existing reviews, articles and video documentation.

“How I Became a Boogie-Down Rican” explores the performance work of an experientially informed, next-level socially engaged, community-based practice from my experiences in the borough.

An engagement with Familias shows how the artists’ work and their way of working offer a local legacy of impact that continues to inspire.


identifier: Li, Yang  (2014) The Relative Importance of Investment Policy and Active Management in Explaining Canadian Mutual Fund Return Variations and Performance.  Masters thesis, Concordia University.

abstract: Three main factors affect mutual fund returns; namely, market movements, investment policy, and active management. In this thesis, we use fifteen years of data to examine each factor’s role in explaining return variations for Canadian balanced and equity funds, and their performances relative to their respective policy benchmarks. We find that active management plays a more important role in explaining both intra- and inter-fund return variations than investment policy after controlling for market effects, and that there is an incremental effect on the importance of active management if we add the constraint of no short selling to policy return portfolios. We also find that active management does not outperform the policy benchmark after controlling for fund size and risk.


identifier: Soltani Rad, Javad  (2015) A Comprehensive Study on Tool Condition Monitoring Using Time-Frequency Transformation and Artificial Intelligence.  Masters thesis, Concordia University.

abstract: Tool failure is one of the probable faults during machining process which may cause unscheduled downtime and damage of tools, machines and work pieces. Therefore, developing an accurate and reliable online tool condition monitoring (TCM) system is in high demand. This research investigates TCM using time-frequency transformation methods and artificial intelligence. Multi-sensory monitoring systems and sensor fusion are investigated in the first step. Many different sensors at various locations are tested to determine the best input sets with most complimentary information. Three data fusion techniques 1) feature level, 2) score level, and 3) decision level are implemented and compared in this step. The result suggests that score level data fusion is superior for this application. Moreover, five advanced time-frequency transformation methods are employed due to superior ability of time-frequency transformation to reveal time variant characteristics of a signal as well as its frequency components. S-transform demonstrates the most accurate results among these methods. This research also proposes a novel feature extraction method to select the most discriminative information and reduce data’s dimensionality and calculation cost. This method selects a local region of data in time-frequency domain using genetic algorithm optimization. The proposed method is also combined with 2D principal component analysis which has improved the systems in terms of accuracy and performance. Finally, three well-known artificial intelligence methods 1) multi-layer perceptron artificial neural network, 2) radial basis function artificial neural network and 3) adaptive neuro-fuzzy inference system are applied to find a model between extracted features and system fault. Based on the results, radial basis function has the minimum mean error and adaptive neuro-fuzzy produces the lowest maximum error.


identifier: Khajooeizadeh, Anahid  (2015) Applications of cryptanalysis methods to some symmetric key primitives.  Masters thesis, Concordia University.

abstract:
Block ciphers and hash functions are important cryptographic primitives that are used to secure the exchange of critical information. With the continuous increase in computational power available to attackers, information security systems including their underlying primitives need continuous improvements. Various cryptanalysis methods are used to examine the strength and weakness of hash functions and block ciphers.
In this work, we study the Lesamnta-512 and DHA-256 hash functions and the LAC authenticated encryption scheme. In particular, we study the resistance of the underlying block cipher of the Lesamnta-512 hash function against impossible differential attacks, the resistance of the DHA-256 compression function against collision attacks. We also study MAC forgery attacks against LAC. Throughout our analysis, we use different automated methods to facilitate our analysis.
For the cryptanalysis of Lesamnta-512, two automated methods are studied for finding an impossible differential path with the maximum length. Using the obtained impossible differential path, impossible differential cryptanalysis of Lesamnta-512 is performed for 16 rounds. For the DHA-256 hash function, we used an algebraic method to find collisions for its 17-step reduced compression function by deriving difference equations for each step and then solving them when the conditions for collisions are imposed on these equations.
For LAC, the differential behavior of the different operations of the cipher is represented into a set of linear equations. Then, a Mixed Integer Linear Programming (MILP) approach  is used to find a high probability characteristic. This characteristic is then used to perform a forgery attack on LAC encryption authenticated cipher.


identifier: Danesh Shahraki, Omid  (2015) OPTIMAL LEADER-FOLLOWER FORMATION CONTROL USING DYNAMIC GAMES.  Masters thesis, Concordia University.

abstract:
Formation control is one of the salient features of multi-agent robotics. The main
goal of this field is to develop distributed control methods for interconnected multi-robot systems so that robots will move with respect to each other in order to keep a
formation throughout their joint mission. Numerous advantages and vast engineering
applications have drawn a great deal of attention to the research in this field.
Dynamic game theory is a powerful method to study dynamic interactions among
intelligent, rational, and self-interested agents. Differential game is among the most
important sub-classes of dynamic games, because many important problems in engineering
can be modeled as differential games.
The underlying goal of this research is to develop a reliable formation control
algorithm for multi-robot systems based on differential games. The main idea is to benefit from powerful machinery provided by dynamic games, and design an improved
formation control scheme with careful attention to practical control design requirements,
namely state feedback, and computation costs associated to implementation.
In this work, results from algebraic graph theory is used to develop a quasi-static optimal
control for heterogeneous leader{follower formation problem. The simulations
are provided to study capabilities as well as limitations associated to this approach.
Based on the obtained results, a finite horizon open-loop Nash differential game is
developed as adaptation of differential games methodology to formation control problems
in multi-robot systems. The practical control design requirements dictate state-feedback;
therefore, proposed controller is complimented by adding receding horizon
approach to its algorithm. It leads to a closed loop state-feedback formation control.
The simulation results are presented to show the effectiveness of proposed control
scheme.


identifier: Yang, Tingting  (2015) A Numerical and Experimental Investigation of Enhanced Open-Loop Air-Based Building-integrated Photovoltaic/Thermal (BIPV/T) Systems.  PhD thesis, Concordia University.

abstract:
This thesis investigates air-based building integrated photovoltaic/thermal (BIPV/T) systems. A building-integrated photovoltaic/thermal (BIPV/T) system converts solar energy into electricity and useful heat, while also serving as the functional exterior layer of the building envelope and thereby achieving the design of net-zero energy buildings.
A comprehensive literature survey of a variety of BIPV/T systems points out the need to develop enhanced air-based BIPV/T systems with aesthetical and mechanical requirements taken into account. This thesis examines improved designs of open-loop air-based BIPV/T systems both numerically and experimentally. A BIPV/T design with two inlets was proposed and a prototype using custom-made frameless PV modules was constructed for feasibility validation. The experiments were performed using a solar irradiance simulator and included testing under varying irradiance levels, flow rates and wind speeds. Experimental results validated that the two-inlet BIPV/T concept improved thermal efficiency by 5% compared to a conventional single-inlet system. Detailed BIPV/T channel air temperature measurements showed that the mixing of the warm outlet air from the first section and the cool ambient air drawn in from the second inlet contributes to the improved performance of the two-inlet system. The heat transfer characteristics in the BIPV/T channel between air and PV panel was studied through the development of Nusselt number correlations. Comparative tests were also conducted on a prototype using opaque mono-crystalline PV modules and a prototype using semi-transparent mono-crystalline PV modules. Results showed that applying semi-transparent PV modules (with 80% module area covered by solar cells) in BIPV/T systems increased thermal efficiency (ratio between the thermal energy recovered by the channel air and solar energy incident on the upper surface of PV) by up to 7.6% compared to opaque ones, particularly when combined with multiple inlets.
A variation of this two-inlet BIPV/T design that includes a vertical solar air heater embedded with a packing material (wire mesh) was presented and analyzed. The additional solar air heater receives high amount of solar energy during the winter period when solar altitude is low, enabling the outlet air to be heated to a higher temperature. A lumped parameter thermal network model of this BIPV/T system was verified using experimental data obtained for a single-inlet BIPV/T prototype. Simulation results indicate that the application of two inlets on a BIPV/T collector increases thermal efficiency by about 5% and increases electrical efficiency marginally. An added vertical glazed solar air collector improves the thermal efficiency by about 8%, and the improvement is more significant with wire mesh packing in the collector by an increase of about 10%. A case study is performed using this lumped thermal model and showed that the thermal efficiency of a BIPV/T roof of an existing solar house is improved by 7% with four air inlets. In conclusion, this thesis presents validated models for the design of open-loop BIPV/T air systems with multiple inlets and possibly semi-transparent PV covers.


identifier: Picard, Alan  (2015) Three Essays in Asset Pricing.  PhD thesis, Concordia University.

title: Three Essays in Asset Pricing

abstract:
Abstract

 This dissertation consists of three essays. My first paper re-examines the link between idiosyncratic risk and expected returns for a large sample of firms in both developed and emerging markets. Recent studies using Fama-French three factor models have shown a negative relationship between idiosyncratic volatility and expected returns for developed markets. This relationship has not been studied to date for emerging markets. This study relates the current-month’s idiosyncratic volatility to the subsequent month’s returns for a sample of both developed and emerging markets expanding benchmark factors by including both a momentum and a systematic liquidity risk component.

 My second essay contributes to the important literature on the topic of the small capitalization stocks historical outperformance over large capitalization stocks by investigating the hypothesis that the small firm premium is related to macroeconomic and financial variables and that relationship is driven by the economic cycle in the United States and Canada. More specifically, this study employs recent advances in nonlinear time series models to explore the relationship between the small firm premium, and financial and macroeconomic variables in the Canadian and U.S. economies.

 My third paper re-examines the findings of a recent research paper that suggested that market wide liquidity may act as a leading indicator to the economic cycle. Using several liquidity measures and various macroeconomic variables to proxy for the economic conditions, the paper presents evidence that stock market liquidity could forecast business cycles: A major decrease in the overall level of market liquidity could indicate weak economic growth in the subsequent months. However, the drawback in the analysis is that the relationship is investigated in a linear approach even though it has been proven that most macroeconomic variables follow non-linear dynamics. Employing similar liquidity measures and macroeconomic proxies, and two popular econometrics models that account for non-linear behavior, this study hence re-investigates the relationship between stock market liquidity and business cycles.


identifier: Gholizadeh Toochaei, Mohammad Reza  (2015) Profit Analysis of Green Products in New Product Development.  Masters thesis, Concordia University.

abstract: The increasingly negative effects of product development and manufacture on the environment are pushing firms to move towards producing new generations of products, i.e. green products. However, the financial effect of green products in the future is a main concern for managers in charge of new product development (NPD) projects. This research focuses on profit analysis of a new product, which is designed based on recyclability, environmentally friendly disposal, and an energy and emission efficiency strategy, in order to equip decision makers with a proper forecast of profitability of such green new products. In this research, first, a primary mixed integer model is proposed to assess the trade-off analysis of green products based on the Cost Volume Profit model in a life-cycle framework. Then, the model is developed based on dynamic programming and a quantitative choice model is applied in the automotive industry. Finally, two numerical examples are used to evaluate the models. The results show the interaction between profitability and environment-friendly attributes of products based on recyclability, disassembly, and an environmentally friendly disposal strategy. It also provides a decision support methodology for management in order to decide about the future of the project during the business analysis stage of the new product development process.


identifier: Yang, T.  (2015) A Numerical and Experimental Investigation of Enhanced Open-Loop Air-Based Building-integrated Photovoltaic/Thermal (BIPV/T) Systems.  PhD thesis, Concordia University.


identifier: Saeidianmanesh, Mehdi  (2015) Group Pathfinding Using Group Division.  Masters thesis, Concordia University.

title: Group Pathfinding Using Group Division

abstract:
Pathfinding is an important problem in video games. Good pathfinding strategy, for both player characters and non-player characters is one of the key differences between a good game and a less successful one. Finding the shortest path for one character unit in a given environment is a very well-known problem for which there exist many solutions. When a group of units wants to pass through the map, the problem becomes more complicated. This thesis introduces the Reduced Wait Time (RWT) algorithm which is a multi-unit path planning algorithm where units can take several paths instead of just the shortest one to reduce the overall waiting time of the units in queues along the path and therefore reduces the total time needed to pass all units through the map.
The main goal of this thesis is propose the pathfinding algorithm RWT to reduce the total time for a group of units to pass a route. The simulation results shows that the RWT algorithm not only reduces the time to pass by decreasing the waiting time, but also can reduce the number of collisions between units which reduces the CPU usage which is another important consideration for games. Using the RWT algorithm also gives an opportunity to the level designers to be able to implement strategic pathfinding in games. Different routes have different strategic advantages and disadvantages over each other; being able to send units through different paths enables designers to consider strategic path-planning.
The RWT algorithm was implemented using the Unity game engine and tested on a number of randomly generated example maps. The experimental results were compared with the results from other related algorithms such as Local Repair A* and Maximum Flow to show that the RWT algorithm works better than other studied algorithms.


identifier: Yip, Samson  (2015) A Comparative Analysis of Passive and Active Daylight Redirecting Blinds in Support of the Schematic Design Process.  Masters thesis, Concordia University.

abstract:
Daylight redirecting blinds are a class of sun control device that are designed specifically to increase daylighting levels in buildings in addition to preventing unwanted solar gain and glare. Because they rely on many parameters such as complex geometry and may require automated controls to achieve their high illuminance performance, their angle-dependent optical characteristics cannot be represented or simulated accurately using the simple tools that are normally used at the beginning of the design process when rapid assessments are needed. Instead they require time- and resource-intensive simulation methods that are difficult to integrate into existing building design workflows at such an early stage of design. Therefore design guidance for these daylight redirecting blinds is needed in support of design decisions at the beginning of the schematic design phase – to assist in answering questions such as: How deep can a floor plate be for the entire floor area in an open-plan office to be considered sufficiently daylit?

The daylighting illuminance performance of two classes of blinds, passive and active, are investigated to generalize this design guidance. A representative model of each class of blind is used. Through the use of a high-performance multi-storey open-plan double-perimeter zone office building in Golden, USA (40°N, 105°W) as a case study, a simplified simulation model using the radiosity method is validated.

The simulation model is used to examine the effect of different parameters such as blind type, location, glazing properties, building depth, façade orientation, window to wall ratio, and window head height on daylighting illuminance in the office space. Simple correlations between building geometry and interior daylight illuminance sufficiency are sought that can be used as design guidance in early schematic design in lieu of simulations.

Based on the results, the conclusion is that for most combinations tested active blinds will perform as well as or better than passive blinds. While a passive blind may be acceptable for mild, temperate climates, it may cause excessive overheating in climates with high cooling loads. In this respect, the greatest flexibility is offered by the class of active blinds which can control when daylight or solar heat is desired in the interior. Using the sDA300/50 metric from the IES LM-83-12 standard, the study found that the maximum building depth for South-oriented open-plan space that provides ‘nominally acceptable’ daylight illuminance is 14.5 m for Golden (actual building depth is 18 m). This calculated maximum building depth is between 11.5 m (Vancouver) and 15 m (Montreal) for different locations. This variation is due to the different total annual sunshine hours and visible transmittance of the glazing and blind at different solar incidence angles at each location. A correlation is made between window head height and maximum building depth for an open-plan office space.


identifier: Li, Zhi  (2015) Modeling and Control of Magnetostrictive-actuated Dynamic Systems.  PhD thesis, Concordia University.

abstract:
Magnetostrictive actuators featuring high energy densities, large strokes and fast responses appear poised to play an increasingly important role in the field of nano/micro positioning applications. However, the performance of the actuator, in terms of precision, is mainly limited by  1) inherent hysteretic behaviors resulting from the irreversible rotation of magnetic domains within the magnetostrictive material; and 2) dynamic responses caused by the inertia and flexibility of the magnetostrictive actuator and the applied external mechanical loads. Due to the presence of the above limitations, it will prevent the magnetostrictive actuator from providing the desired performance and cause the system inaccuracy.

This dissertation aims to develop a modeling and control methodology to improve the control performance of the magnetostrictive-actuated dynamic systems. Through thorough experimental investigations, a dynamic model based on the physical principle of  the magnetostrictive actuator is proposed, in which the nonlinear hysteresis effect and the dynamic behaviors can both be represented. Furthermore, the hysteresis effect of the magnetostrictive actuator presents asymmetric characteristics. To capture these characteristics, an asymmetric shifted Prandtl-Ishlinskii (ASPI) model is proposed, being composed by three components: a Prandtl-Ishlinskii (PI) operator, a shift operator and an auxiliary function. The advantages of the proposed model are: 1) it is able to represent the asymmetric hysteresis behavior; 2) it facilitates the construction of the analytical inverse; 3) the analytical expression of the inverse compensation error can also be derived. The validity of the proposed ASPI model and the entire dynamic model was demonstrated through experimental tests on the magnetostrictive-actuated dynamic system.

According to the proposed hysteresis model, the inverse compensation approach is applied for the purpose of mitigating the hysteresis effect. However, in real systems, there always exists a modeling error between the hysteresis model and the true hysteresis. The use of an estimated hysteresis model in deriving the inverse compensator will yield some degree of hysteresis compensation error. This error will cause tracking error in the closed-loop control system. To accommodate such a compensation error, an analytical expression of the inverse compensation error is derived first. Then, a prescribed adaptive control method is developed to suppress the compensation error and simultaneously guaranteeing global stability of the closed loop system with a prescribed transient and steady-state performance of the tracking error. The effectiveness of the proposed control scheme is validated on the magnetostrictive-actuated experimental platform. The experimental results illustrate an excellent tracking performance by using the developed control scheme.


identifier: Mehdi, Mohamad  (2015) Trust and Reputation Management: a Probabilistic Approach.  PhD thesis, Concordia University.

abstract:
Software architectures of large-scale systems are perceptibly shifting towards employing open
and distributed computing. Web services emerged as autonomous and self-contained business applications that are published, found, and used over the web. These web services thus exist in an environment in which they interact among each other to achieve their goals. Two challenging tasks that govern the agents interactions have gained the attention of a large research community;
web service selection and composition. The explosion of the number of published web services contributed to the growth of large pools of similarly functional services. While this is vital for a competitive and healthy marketplace, it complicates the aforementioned tasks. Service consumers resort to non-functional characteristics of available service providers to decide which service to interact with. Therefore, to optimize both tasks and maximize the gain of all involved agents, it is essential to build the capability of modeling and predicting the quality of these agents.
In this thesis, we propose various trust and reputation models based on probabilistic approaches to address the web service selection and composition problems. These approaches consider the trustworthiness of a web service to be strongly tied to the outcomes of various quality of service metrics such as response time, throughput, and reliability. We represent these outcomes by a multinomial distribution whose parameters are learned using Bayesian inference which, given a likelihood function and a prior probability, derives the posterior probability. Since the likelihood, in this case, is a multinomial, a commonly used prior is the Dirichlet distribution. We propose, to
overcome several limitations of the Dirichlet, by applying two alternative priors such as the generalized
Dirichlet, and Beta-Liouville. Using these distributions, the learned parameters represent the probabilities of a web service to belong to each of the considered quality classes. These probabilities are consequently used to compute the trustworthiness of the evaluated web services and thus assisting consumers in the service selection process. Furthermore, after exploring the correlations
among various quality metrics using real data sets, we introduce a hybrid trust model that captures these correlations using both Dirichlet and generalized Dirichlet distributions. Given their covariance structures, the former performs better when modeling negative correlations while the latter yields better modeling of positive correlations. To handle composite services, we propose various trust approaches using Bayesian networks and mixture models of three different distributions; the multinomial Dirichlet, the multinomial generalized Dirichlet, and the multinomial Beta-Liouville. Specifically, we employ a Bayesian network classifier with a Beta- Liouville prior to enable the classification of the QoS of composite services given the QoS of its constituents. In addition, we extend the previous models to function in online settings. Therefore, we present a generalized-Dirichlet power steady model that predicts compositional time series. We similarly extend the Bayesian networks model by using the Voting EM algorithm. This extension enables the estimation of the networks parameters after each interaction with a composite web service. Furthermore, we propose an algorithm to estimate the reputation of web services. We extend this algorithm by leveraging the capabilities of various clustering and outlier detection techniques to deal with malicious feedback and various strategic behavior commonly performed by web services.
Alternatively, we suggest two data fusion methods for reputation feedback aggregation, namely, the covariance intersection and ellipsoidal intersection. These methods handle the dependency between the information that propagates through networks of interacting agents. They also avoid over confident estimates caused by redundant information. Finally, we present a reputation model for
agent-based web services grouped into communities of homogeneous functionalities. We exploit various clustering and anomaly detection techniques to analyze and identify the quality trends provided by each service. This model enables the master of each community to allocate the requests it receives to the web service that best fulfill the quality requirements of the service consumers. We evaluate the effectiveness of the proposed approaches using both simulated and real data.


identifier: Tadros, Hani  (2014) Three Essays on Corporate Environmental Disclosures and Environmental Performance.  PhD thesis, Concordia University.

abstract:
The objective of this dissertation is to study the incentives of firms to disclose their environmental information and examine the reliability of the information disclosed. To achieve this objective, there is a need to first understand what constitutes environmental disclosures. The first essay, a review of prior disclosure studies, provides a classification of the different types of environmental disclosures and a synopsis about the motivation to disclose each type of information, the reliability and the relevance of the information disclosed to different stakeholders. The outcome of this research shows that many types of environmental information are relevant to the financial and non-financial stakeholders; however, there are still other types of information that needs to be researched to finally achieve a comprehensive framework of environmental disclosures.
The second essay examines the association between environmental disclosures and firms’ environmental performances. The study provides a framework to explain the disclosure process demonstrating the effect of economic and legitimacy factors, environmental performance, and the media communicating these disclosures on the amount and type of information reported. The results suggest that environmental reporting is biased; where firms with higher levels of environmental performance disclose more voluntary information while firms with low-environmental performance tend to meet the mandatory disclosure requirements. There is little evidence to suggest that firms with low-environmental performances use their environmental disclosures to maintain the legitimacy of their environmental operations.
The third essay examines the reliability of environmental performance indicators disclosed. The results suggest that the reporting of firms’ EPIs might be free of bias as the study finds no association between the information disclosed and firms’ environmental performance.
In general, the dissertation provides assurances over the reliability of environmental information disclosed. There is no denial that firms are subject to pressures from non-financial stakeholders to justify the impact of their operations on the environment.  This dissertation shows that firms attempt to use their environmental disclosures to mitigate the effects of these pressures; however, it also suggests that the need to legitimize their operations is not the main driver behind the reporting of environmental information.


identifier: Noël, Mélissa  (2015) The impact of a Social Customer Relationship Management (SCRM) system on the development of customer engagement in the restaurant industry.  Masters thesis, Concordia University.

abstract:
The main purpose of this research is to examine the impact of a Social Customer Relationship Management (SCRM) system on the development of customer engagement in the restaurant industry.  This study is also aimed at investigating the impact of customer engagement on cognitive and affective commitment, behavioural loyalty, satisfaction, trust and involvement.  We also expect to find a positive impact of customer engagement on other measurements such as revenue growth ratios, sales, frequency of visit, profitability, satisfaction, intentions to revisit, money spent per visit and word-of-mouth referral.

In order to validate the model, a survey was administered to Osco! restaurant and Sarah B. bar patrons.  The results confirmed the validity of the scale, as well as the profile of the customers.  This first round of data collection also confirmed the existence of a positive and significant relationship between customer engagement and the following variables: cognitive and affective commitment, behavioural loyalty, satisfaction and trust.

Then, following the implementation of the Social Customer Relationship Management (SCRM) system, a second survey was administered to the active members of the program.  This confirmed the reliability of the scales once again and it highlighted the differences between the profiles of the customers and the SCRM members. The regression analysis also confirmed the positive and significant relationship between customer engagement and the following variables: behavioural loyalty, satisfaction and trust.  The analysis of the financial results also confirms the impact of the Social Customer Relationship Management (SCRM) system on sales, revenue growth, profitability and average amount spent per visit.


identifier: Abouhamad, Mona  (2014) An Integrated Risk-Based Asset Management Framework for Subway Systems.  PhD thesis, Concordia University.

abstract:
Subway systems play a vital role connecting thousands of people to different destinations on a daily basis. The Canadian infrastructure report card recommended encouraging infrastructure owners to establish asset-management plans based on rates of deterioration and community service levels. Moreover, the 2013 report card for America’s infrastructure assigned a grade D to transit systems indicating they are in a poor condition with strong risk of failure. A possible solution proposed by the 2013 report card is adopting a comprehensive asset management system to maximize investments in light of the fund scarcity dilemma.
The main objective of this research is to develop a risk-based asset management framework for subway networks. The framework works along three interrelated sub-models followed by two main models. A generic subway hierarchy is proposed and risk is assessed using three sub-models; probability of failure, consequences of failure and criticality index. Probability of failure is predicted for different structural elements using inspection reports and Weibull reliability function. Consequences of failure are assessed based on seven criteria along financial, social, and, operational perspectives. A criticality index is introduced to the classical risk equation to assess the functional importance of a station in its location using seven attributes along three main criteria. The Fuzzy Analytical Network Process is employed to analyze experts’ feedback used in the consequences of failure and criticality sub-models. This insures incorporating interdependency between criteria and fuzziness of the analysis. The three sub-models are used as inputs in a fuzzy inference engine to compute the predicted risk index. A set of thirty rules derived from experts through interviews and questionnaires is used to shape the relation between the fuzzy output and input variables. Finally, the second model is developed for a risk-based budget allocation model. The model utilizes the risk index components as objective functions. Decision variables are identified as five generic rehabilitation actions along their cost, time, and percentage improvement. The model provides the recommended rehabilitation action in light of the network total risk index and the available budget per time span.
This is the first risk assessment framework proposed in the subway networks domain. Using a network analysis approach, the elements of a risk index are analyzed and aggregated from elements to lines and segments levels. The model revealed probability of failure to be the main driver of a risk index followed by criticality index and last, consequences of failure. Within the expected consequences of failure, social impacts had the highest impact (38%) based on experts’ feedback. The criticality index sub-model revealed station location to be the most important criteria (35%) followed by station nature of use (33%) and finally, station characteristics (32%). A segment of six stations from Montreal subway network is analyzed. The assessment indicates two stations with high risk indices showing the necessity of an intervention action. The budget allocation model prioritizes stations for rehabilitation according to the decision maker’s risk appetite, assumed at 0.6. The revised risk index for STA 4 dropped from 0.821 to 0.521 and the overall segment index dropped to zero.
This research presents a basis for evaluating subway infrastructure on a structural and functional basis. It assists authorities to derive an informed rehabilitation decision using a generic and consistent framework. The heuristic decision making process followed by authorities is translated into a detailed framework that can be easily implemented and updated. The presented outline can be equally used for segments or the entire network.


identifier: Pan, Yinan  (2015) What determines the success of bidding firms in M&A deals?  Masters thesis, Concordia University.

abstract: We examine the drivers of bidding success in multiple-bidder merger and acquisition (M&A) announcements. We employ a series of logistic regression analyses and find that higher company value, greater profitability, a friendly offer attitude and a compatibility in industry specialization between bidders and targets serve as powerful determinants of the success of a given M&A attempt when multiple bidders are present. Our findings also suggest that if a small bidder (relative to its target) wants to be the final winner among the multiple bidders, the company’s growth opportunities are valued most by the target company’s shareholders. A second research is conducted to estimate a series of cross-sectional regression models to explore the determinants of target and bidder announcement returns respectively. Our findings suggest that the market already knows around the time of the bidding which bidder will be successful (unsuccessful). The stocks of successful bidders display the typical price increase on the announcement date that is contrary to the results documented in the literature whereas the abnormal returns of unsuccessful bidders fluctuate dramatically during the same period, which can be discerned clearly from the successful bidders.


identifier: Yiğen, Serap  (2015) Electronic Thermal Conductivity Measurements in Graphene.  PhD thesis, Concordia University.

abstract:
The electronic thermal conductivity in graphene describes how energy is transported by the charge carriers in graphene, and how these carriers lose their energy via diffusion and interactions with phonons and impurities. Understanding these interactions can shed light on electron-phonon scatterings, thermal relaxation processes, and the electron cooling mechanisms in graphene. We developed a method to experimentally isolate the electronic thermal conductivity in suspended graphene transistors by adapting a Joule self-heating method. We extracted the electronic thermal conductivity, $K_{e}$, as a function of electron temperature and charge carrier density.
We fabricated two-point suspended graphene transistors using micro-fabrication methods. We used the electrical contacts as source and drain to apply a bias voltage and a back-gate electrode to tune the carrier density. We adapted a Joule self-heating method in which we used graphene as its own heater and thermometer. To do so, we prepared thermometry (calibration) curves by measuring low-bias resistance of the graphene devices versus temperature. As we increased the bias voltage, we could measure and control the temperature of electrons. We solved a one-dimensional heat diffusion equation and extracted the electronic thermal conductivity. We studied our samples at low bias voltages and intermediate temperatures where the electron and lattice temperatures are decoupled. This minimized the energy transfer between phonons and charge carriers. Since the suspended devices isolate the graphene crystals from the substrate, there were no interactions with the substrate phonons and no heat leakage to the substrate. Therefore, the heat was diffused only by the charge carriers.
We extracted the electronic thermal conductivity in intrinsic monolayer graphene over a temperature range of 20 to 300 K. We found that $K_{e}$ has a strong temperature dependence, ranging from 0.5 to 11 W/m.K. We compared our data with a model of diffusing charged quasiparticles which have the same mean free path and velocity as graphene's charge carriers. Data from three different devices are in very good agreement with the model, supporting that the heat is carried by diffusing Dirac quasiparticles.
We doped our devices using the back-gate electrode, and extracted $K_{e}$ in doped graphene over a temperature range of 50 to 160 K. We found that $K_{e}$ is proportional to the charge conductivity times the temperature, and thus the Wiedemann-Franz Law is obeyed in suspended graphene. The Lorenz coefficient is estimated to be 1.1 to 1.7 $\times$ 10$^{-8}$ W $\Omega$ K$^{-2}$. We observed a strong thermal transistor effect in our devices as the charge carrier density is changed from $\approx$ 0.5 to 1.8 $\times$ 10$^{11}$ cm$^{-2}$, showing that $K_{e}$ can be tuned by more than a factor of 2 by applying a few volts of gate voltage.
The methods presented here could be extended to bilayer graphene devices and other two-dimensional materials to isolate $K_{e}$ to study electron-electron and electron-phonon interactions. The ability to control $K_{e}$ could be useful for energy harvesting in nano and opto-electronic devices.


identifier: Behrouznia, Saba  (2015) A QoS-based Resource Selection Approach for Virtual Networks.  Masters thesis, Concordia University.

abstract:
The Internet has gained an outstanding success in a short amount of time and it became a critical infrastructure for accessing information and global commerce. With the help of the Internet and its new channels for connecting people a new way of communication has been established. Meanwhile, its great success leads to new limitations. The Internet consists of various network infrastructure providers with different objectives which makes emerging of new technologies or major architectural changes that require cooperative agreements, relatively impractical. While the current Internet architecture is not suitable for supporting many types of applications, network virtualization is considered as promising, yet challenging solution of these limitations. Network virtualization separates the role of traditional internet service providers (ISPs) into physical infrastructure providers (PIPs) responsible for deploying the physical infrastructure and service providers (SPs) offering end-to-end services to end users. Another motivation for network virtualization is the possibility to add value in the virtualization layer aiming to make use of new technologies (e.g. QoS schemes) and customizing existing technologies to adapt specific services (i.e. customizable networks). This provides the means to run multiple virtual networks on a shared substrate network simultaneously while each virtual network is customized for a specific use.
The key challenge in virtual networks is the problem of assigning virtual nodes and links to physical resources. Virtual network mapping/embedding consists in finding the most suitable physical nodes and links in the physical network in order to map virtual network requests with certain constraints on virtual nodes and links. The goal of this thesis is to design and implement substrate network resource selection scheme to increase the overall efficiency of the virtual network embedding process and satisfy the set of predefined resource constraints. This work assumes the existence of a virtual infrastructure provider requesting virtual networks from physical infrastructure providers and proposes a selection algorithm based on service-oriented architecture. Our proposed virtual network embedding algorithm is a heuristic algorithm that considers static attributes along with dynamic attributes of nodes and links as well as end-to-end QoS constraints.


identifier: Rema, Sawan  (2014) Modeling Cost of Quality in the Construction Industry A closer look at the Procurement Process using System Dynamics.  Masters thesis, Concordia University.

abstract: The aim of this research is to develop the Cost of Quality (COQ) model for the procurement process of the construction industry and establish a general course of action for minimizing quality costs. A case study in a large Canadian construction company was conducted and the use of the Prevention-Appraisal-Failure (PAF) approach for the COQ model of the procurement process was explored. In contrast to the conventional COQ analysis we take into account not only the internal quality costs within the company, but also the costs of its suppliers. Several different policies were designed and their effects on quality costs investigated through System Dynamics (SD) simulation. The findings suggest that Prevention costs should be increased to minimize failures. It was also found that Appraisal cost is quite high in the procurement process and should be reduced in order to minimize overall COQ. However, this strategy could increase failure occurrences thereby damaging a company’s reputation. The possible reductions of Appraisal cost in the construction companies should thus be carefully considered.


identifier: Sheepy, Emily  (2015) Get Water!: Exploring the Adult Player’s Experience of a Mobile Game for Change.  Masters thesis, Concordia University.

abstract:
Research problem: Games with civic themes such as Get Water! are intended to raise awareness and promote participation in social movements. Evidence linking the features of such games to specific player outcomes, including affective, cognitive and behavioral indicators of learning, is limited. The purpose of this study is to contribute to the literature on game-based civic education by conducting an in-depth investigation of the experiences of adult players of a social change game for mobile devices, Get Water!.
Research questions: (1) How do players experience Get Water!? (2) How do players evaluate Get Water!? (3) Does playing Get Water! influence players’ attitudes, thoughts or actions related to the social issues it addresses?
Literature review: Previous research suggests that prior experience may influence how players interpret video games. Though some games with civic themes have been found to positively affect player attitudes and promote learning, the mechanisms are unclear. Design features of such games, especially content-mechanic integration, are likely to influence attitudinal, cognitive and behavioral learning outcomes of play by structuring the player experience.
Methodology: A qualitative case study approach is used to characterize the experiences and evaluations of 22 adults who played the game in a laboratory setting. Participant data was collected using a think-aloud procedure, post-play questionnaires, semi-structured interviews, and a one-month follow-up questionnaire. External data, including game design documents, were also examined. Descriptive and interpretive analyses were conducted to develop a detailed description of player-game interactions and player perceptions.
Findings and Conclusions: The data suggest that the participants’ evaluations of the game were informed by their personal experiences of the social issue depicted, and values with regards to teaching and learning. As such, their interpretations of the game’s content and perceived effectiveness varied greatly. Notably, the interpretations of players who had personally lived in regions where water scarcity exists interpreted the social messaging in unexpected ways. While the players largely enjoyed the game and viewed it positively, some indicated that the in-game activities were not sufficiently representative of the real-world scenario to afford a transformative educational experience. Misalignment between in-game objectives and real-world motives, and limited character and narrative development may account for the players’ experiences of low affective identification with the player character.  Some players engaged in discussion and sought information about the subject matter in the month after the laboratory session. The findings and implications contribute to a conceptual understanding of how differences at the player level can influence how a social change game is experienced and evaluated. This suggests that social change game designers and education practitioners should prioritize representational verification efforts to better accommodate diversity in players’ prior knowledge.


identifier: Ribeiro, Ofelia  (2015) Becoming a Clinical Educator: An Exploration of What Clinical Educators Do and How They Prepare to Teach in a Healthcare Setting.  PhD thesis, Concordia University.

abstract:
Clinical educators are experienced professionals who, in the course of performing their regular jobs, teach, supervise and assess students in a workplace-based practicum. Although research has identified problems in the ways clinical educators fulfill their roles and responsibilities, little is known of their daily experiences or how they prepare to teach, as well as the complexities of clinical settings that may contribute to these problems. Because clinical educators rarely receive any formal preparation in teaching methods and what little preparation they receive is voluntary, this study aims to understand the primarily informal learning processes (both micro and macro) by which these professionals become clinical educators and how these help them in their daily practice in their healthcare work settings.

This dissertation reports on an exploratory multiple case study where participants from four allied health professions serve as cases. Data was collected through in-depth interviews, observations, and documents. Several layers of analysis of the data, together with fieldnotes, yielded a model of the experience of becoming a clinical educator. The power of this model lies in that it emerged from the data gathered and is richly illustrated with the voices of the participants.

Findings from this research present the act of becoming a clinical educator as evolving through professional socialization in the workplace. It is embedded in the context of professional practice and is therefore best learned in this context of becoming and developing as a health professional. It is anticipated that this examination of teaching and learning in the healthcare workplace will add to the body of knowledge of workplace learning in healthcare settings, as teaching and learning in the healthcare workplace is a complex and individual experience. The model provides a way to conceptualize the practices of clinical educators, their development within the role, refinements in practice, and suggestions for future research.


identifier: Fu, Yang  (2015) Regression Based Gaze Estimation with Natural Head Movement.  Masters thesis, Concordia University.

abstract:
This thesis presents a non-contact, video-based gaze tracking system using novel eye detection and gaze estimation techniques. The objective of the work is to develop a real-time gaze tracking system that is capable of estimating the gaze accurately under natural head movement. The system contains both hardware and software components. The hardware of the system is responsible for illuminating the scene and capturing facial images for further computer analysis, while the software implements the core technique of gaze tracking which consists of two main modules, i.e., eye detection subsystem and gaze estimation subsystem.
The proposed gaze tracking technique uses image plane features, namely, the inter-pupil vector (IPV) and the image center-inter pupil center vector (IC-IPCV) to improve gaze estimation precision under natural head movement. A support vector regression (SVR) based estimation method using image plane features along with traditional pupil center-cornea reflection (PC-CR) vector is also proposed to estimate the gaze.
 The designed gaze tracking system can work in real-time and achieve an overall estimation accuracy of 0.84º with still head and 2.26º under natural head movement. By using the SVR method for off-line processing, the estimation accuracy with head movement can be improved to 1.12º while providing a tolerance of 10cm×8cm×5cm head movement.


identifier: Srinivasan, Ashok  (2014) Integrating Block Layout Design and Location of Input and Output Points in Facility Layout Problems.  Masters thesis, Concordia University.

abstract: A well designed facility layout consists of an adequate arrangement of departments and an efficient material handling system that minimizes the total material handling cost between departments. Block layout design and input and output (I/O) points location are the two major decisions in that need to be made when designing the layout of a facility. Although both decisions are interrelated, the classical approach to facility layout design is to consider them independently. In this thesis, an integrated approach to design the block layout and to locate the I/O points is presented. In particular, we consider three different cases: (i) block layout design with fixed I/O points, (ii) block layout design with flexible I/O points, and (iii) block layout design with flexible department shapes and flexible I/O points. Four mixed integer programming (MIP) formulations are presented for these facility layout problems, with the objective of minimizing the total material handling cost. A case study of a manufacturing company is used to evaluate the performance of the proposed models. A comparison is performed between the existing and proposed layouts. These proposed layouts provide estimated savings of 50% and more as compared with the existing layout.


identifier: Enayat, Maria  (2015) Cooperative Control and Fault Recovery for Network of Heterogeneous Autonomous Underwater Vehicles.  Masters thesis, Concordia University.

abstract:
The purpose of this thesis is to develop cooperative recovery control schemes for a team of heterogeneous autonomous underwater vehicles (AUV). The objective is to have the network of autonomous underwater vehicles follow a desired trajectory while agents maintain a desired formation. It is assumed that the model parameters associated with each vehicle is different although the order of the vehicles are the same.

Three cooperative control schemes based on dynamic surface control (DSC) technique are developed. First, a DSC-based centralized scheme is presented in which there is a central controller that has access to information of all agents at the same time and designs the optimal solution for this cooperative problem. This scheme is used as a benchmark to evaluate the performance of other schemes developed in this thesis.

Second, a DSC-based decentralized scheme is presented in which each agent designs its controller based on only its information and the information of its desired trajectory. In this scheme, there is no information exchange among the agents in the team. This scheme is also developed for the purpose of comparative studies.

Third, two different semi-decentralized or distributed schemes for the network of heterogeneous autonomous underwater vehicles are proposed. These schemes are a synthesis of a consensus-based algorithm and the dynamic surface control technique with the difference that in one of them the desired trajectories of agents are used in the consensus algorithm while in the other the actual states of the agents are used.
In the former scheme, the agents communicate their desired relative distances  with the agents within their set of nearest neighbors and each agent determines its own control trajectory. In this semi-decentralized scheme, the velocity measurements of the virtual leader and all the followers are not required to reach the consensus formation. However, in the latter,  agents communicate their relative distances and velocities with the agents within their set of nearest neighbors.
In both semi-decentralized schemes only a subset of agents has access to information of a virtual leader. The comparative studies between these two  semi-decentralized schemes are provided which show the superiority of the former semi-decentralized scheme over latter.

Furthermore, to evaluate the efficiency of the proposed DSC-based semi-decentralized scheme with consensus algorithm using desired trajectories, a comparative study is performed between this scheme and three cooperative schemes of model-dependent coordinated tracking algorithm, namely the centralized, decentralized, and semi-decentralized schemes.

Given that the dynamics of autonomous underwater vehicles are inevitably subjected to system faults, and in particular the actuator faults, to improve the performance of the network of agents, active fault-tolerant control strategies corresponding to the three developed schemes are also designed to recover the team from the loss-of-effectiveness in the actuators and to ensure that the closed-loop signals remain bounded and the team of heterogeneous autonomous underwater vehicles satisfy the overall design specifications and requirements.

The results of this research can potentially be used in various marine applications such as underwater oil and gas pipeline inspection and repairing, monitoring oil and gas pipelines, detecting and preventing any oil and gas leakages. However, the applications of the proposed cooperative control and its fault-tolerant scheme are not limited to underwater formation path-tracking and can be applied to any other multi-vehicle systems that are characterized by Euler–Lagrange equations.


identifier: Vongas, John G.  (2015) Competition, Power, and Testosterone: How Winning and Losing Affect Men’s Empathic Accuracy and Aggression.  PhD thesis, Concordia University.

abstract: This thesis investigates the effects of winning and losing on men’s testosterone and how these hormonal changes impact their emotion recognition ability or ‘empathic accuracy’ (Study 1) and their aggression (Study 2).  It also explores how men’s personalized power motivation – their drive to influence other people for self-aggrandizing purposes – moderates the relationships between the competitive outcomes they experienced and their accuracy and aggression.  In Study 1, 84 males competed in dyads on a spatial-cognitive task that allegedly gauged their leadership potential, future earnings, and likelihood of career success after which they interpreted people’s emotional expressions from static photographs.  Results showed that winners’ testosterone decreased while that of losers increased.  Second, winners were more capable of accurately inferring others’ emotions compared to losers and this ability improved with increasing personalized power.  Third, testosterone change mediated the relationship between competitive outcomes and empathic accuracy, with post-competitive increases in testosterone relating to increases in accuracy.  In Study 2, 72 males competed again in dyads after which they participated in two sequential tasks that measured their unprovoked (‘proactive’) and provoked (‘reactive’) aggression. As in Study 1, losers experienced a post-competitive testosterone increase, whereas winners experienced a decrease.  However, neither competitive outcome nor testosterone change had a significant effect on proactive and reactive aggression.  Moreover, as men’s personalized power increased, winners aggressed more proactively than losers, whereas losers aggressed more reactively than winners.  Collectively, these are the first studies to explore how winning and losing interact with men’s personalized power motivation to affect various empathic responses. This research is important because we know little about what happens to behaviours and cognitions in the aftermath of a status-based contest.  Given that competition is encouraged in many organizations and the workplace is a social setting in which zero-sum games are played out each day, findings from this research could assist managers in fostering healthier competitive work climates.  Finally, among the myriad of future avenues worth pursuing, I particularly recommend that scholars look into how competition, personalized power, and endocrine changes jointly affect women’s empathic accuracy and aggression.


identifier: Wan, Wei  (2014) Probabilistic and Epistemic Model Checking for Multi-Agent Systems.  PhD thesis, Concordia University.

abstract:
Model checking is a formal technique widely used to verify security and communication protocols in epistemic multi-agent systems against given properties. Qualitative
properties such as safety and liveliness have been widely analysed in the literature. However, systems also have quantitative and uncertain (i.e., probabilistic) properties such as degree of reliability and reachability, which still need further attention from the model checking perspective. In this dissertation, we analyse such properties and present a new method for probabilistic model checking of epistemic multi-agent
systems specified by a new probabilistic-epistemic logic PCTLK. We model multiagent systems distributed knowledge bases using probabilistic interpreted systems. We also define transformations from those interpreted systems into discrete-time Markov chains and from PCTLK formulae to PCTL formulae, an existing extension of CTL with probabilities. By so doing, we are able to convert the PCTLK model checking problem into the PCTL one. We address the problem of verifying probabilistic properties
and epistemic properties in concurrent probabilistic systems as well. We then prove that model checking a formula of PCTLK in concurrent probabilistic systems is
PSPACE-complete. Furthermore, we represent models associated with PCTLK logic symbolically with Multi-Terminal Binary Decision Diagrams (MTBDDs).

Finally, we make use of PRISM, the model checker of PCTL without adding new computation cost. Dining cryptographers protocol is implemented to show the
applicability of the proposed technique along with performance analysis and comparison in terms of execution time and state space scalability with MCK, an existing
epistemic-probabilistic model checker, and MCMAS, a model checker for multi-agent systems. Another example, NetBill protocol, is also implemented with PRISM to verify probabilistic epistemic properties and to evaluate the complexity of this verification.


identifier: Hanukov, Ilana  (2015) Exposing Celebrity Scandal: How Journalism, Fame, and Audiences Coincide.  Masters thesis, Concordia University.

abstract: This thesis explores the world of celebrity scandal, investigating what happens when journalists report on star transgressions that disrupt prevailing codes of behaviour. The central assertion of this thesis is that in circulating controversy, journalists ultimately strive not to inform or to educate the public, but rather to gain audiences and sell papers. The analysis, intertwining cultural and political-economic viewpoints, is guided by two overarching goals: to address the elements that give celebrity scandal its resonance within contemporary culture, and to clearly delineate how these elements are mobilized to reap the full economic benefits of scandal. Three case studies, involving Kate Moss, Lance Armstrong, and Charlie Sheen, are examined to expose the mutually dependent relationship between the key players in scandal stories: those reporting (journalists), those being reported on (celebrities), and those responding (audiences). Concentrating on what drives scandal news circuits and who benefits from these stories, this study aims to open the door to wider explorations of journalistic practices in times of controversy.


identifier: Sanchez Marquez, Jose Miguel  (2015) Influence of Saturation and Geometry on Surface Electrical Resistivity Measurements.  Masters thesis, Concordia University.

abstract: Non-destructive tests are the future for early concrete deterioration detection. The interest in surface electrical resistivity as for the quality control of concrete structures has increased in the last several years. A standardized laboratory method has recently been adopted as AASHTO TP 95-11 and an ASTM method is under consideration. Both these methods measure surface resistance by a Wenner four-electrode probe device, in which the electrodes are equally spaced on the surface of saturated concrete elements. Currently, the standardized method is restricted to laboratory specimens. For this method to be applicable to field measurements requires first to identify how much time a concrete element needs to reach saturation and how reliable resistivity values are under different saturation stages. Phase one of this research investigated the duration of saturation required to achieve stable resistivity for 20 mixture designs at a range of ages. It was generally determined that resistivity varies until 24 hours. Past that duration, some increases in surface resistivity were observed and attributed to further hydration. In the field, concrete elements are generally large and the assumptions of infinite geometry hold. Lab specimens, on the other hand, have a constricted flow of electrical current. In Phase two, the influences of geometry and saturation fluid were examined. It was found that using published geometrical conversion factors did not result in equivalent surface resistivity between cylinders and small slabs or for cylinders of different sizes, suggesting more work required in this area. The use of tap water was investigated as it would be more available on site; it was found that at 28 days, there were minimal differences between tap water and limewater. At later ages, limewater generally resulted in higher resistivity. Phase Three investigated published temperature corrections to adjust site measured resistivity to standard temperature. Regardless of the correction, significant difference was observed between the site and laboratory measurements. Lastly in Phase four, two alternate techniques were tested for potential on site use. It was found that neither resulted in any significant changes in resistivity.


identifier: Rejali, MohammadReza  (2015) Effective Segmentation of Large Execution Traces Using Probabilistic and Gaussian Mixture Models.  Masters thesis, Concordia University.

abstract:
Software maintenance is known to be a costly and time consuming activity. Software engineers need to spend a considerable amount of time in understanding the system before maintaining it. This is due to many reasons including the lack of good documentation and the shift of the original developers of the system to other projects or companies.
Dynamic analysis techniques, more particularly trace analysis, are used to alleviate the program comprehension problem by offering software engineers a set of techniques that can help them understand the behavioural aspects of software systems.
Execution traces however can be extremely large, which makes them cumbersome for effective analysis. There is a need to develop techniques to help software engineers understand the content of large traces despite their massive size. In this thesis, we present, SumTrace, a novel trace analysis technique. SumTrace takes a trace as input and automatically segments it into smaller and more manageable groups that reflect the execution phases of the traced scenario. The execution phases are summarized to help software engineers understand quickly different parts of the trace without having to analyze its entire content. SumTrace relies on a combination of probabilistic and Gaussian mixture models.
We applied SumTrace to the segmentation of large traces, generated from two software systems. The results are very promising. SumTrace is also fast since it only requires only one pass through a trace.


identifier: Zhang, Xin  (2015) Experimental Investigation of the Ternary Mg-Zn-Zr System.  Masters thesis, Concordia University.

abstract:
The Mg-Zn-Zr ternary system was experimentally investigated at 450oC using six diffusion couples and 16 key alloys. Four new ternary compounds, namely as IM1, IM2, IM3 and IM4 were detected. The compositions, homogeneity ranges and the XRD patterns of these compounds were identified in this system using Scanning Electron Microscopy coupled with Energy-dispersive X-ray spectroscopy and X-ray Diffraction techniques. The homogeneity ranges of IM1, IM2, IM3 and IM4 are Mg(23-26)Zn66Zr(8-11), Mg(15-16)Zn66Zr(18-19), Mg(10-11)Zn66Zr(23-24), and Mg(9-13)Zn(79-87)Zr(5-8) respectively. IM1 compound is determined to have the same prototype as the MgZn2 phase with the hexagonal structure and P63/mmc space group. The binary compounds do not have extended solid solubility into the ternary system. The XRD patterns of IM2, IM3 and IM4 were obtained from key alloys study. The liquid area in the Mg-Zn-Zr ternary system at 450oC was verified by several key alloys. Although large regions of liquid exist in the binary phase diagrams at 450 oC, the single phase liquid region extended only around 1 at.% into the ternary phase diagram. Two and three-phase regions that contain liquid are up to around 10 at.% Zr. Based on the current experimental results of diffusion couples and equilibrated key alloys, the isothermal section of the Mg-Zn-Zr ternary system at 450oC has been constructed.

Studying this system was challenging due to the large difference in melting points of its components. In order to overcome this problem, Zn-Zr master alloys were prepared to obtain homogenous key samples and to solve the problem of elements evaporation. In addition, two-step annealing methods were used to study the microstructure changes of the key alloys.


identifier: Al Mashrgy, Mohamed  (2015) Positive Data Clustering based on Generalized Inverted Dirichlet Mixture Model.  PhD thesis, Concordia University.

abstract:
Recent advances in processing and networking capabilities of computers have caused an accumulation
of immense amounts of multimodal multimedia data (image, text, video). These data
are generally presented as high-dimensional vectors of features. The availability of these highdimensional
data sets has provided the input to a large variety of statistical learning applications
including clustering, classification, feature selection, outlier detection and density estimation. In
this context, a finite mixture offers a formal approach to clustering and a powerful tool to tackle
the problem of data modeling. A mixture model assumes that the data is generated by a set of
parametric probability distributions. The main learning process of a mixture model consists of the
following two parts: parameter estimation and model selection (estimation the number of components).
In addition, other issues may be considered during the learning process of mixture models
such as the: a) feature selection and b) outlier detection. The main objective of this thesis is to
work with different kinds of estimation criteria and to incorporate those challenges into a single
framework.
The first contribution of this thesis is to propose a statistical framework which can tackle the problem
of parameter estimation, model selection, feature selection, and outlier rejection in a unified
model. We propose to use feature saliency and introduce an expectation-maximization (EM) algorithm
for the estimation of the Generalized Inverted Dirichlet (GID) mixture model. By using
the Minimum Message Length (MML), we can identify how much each feature contributes to
our model as well as determine the number of components. The presence of outliers is an added
challenge and is handled by incorporating an auxiliary outlier component, to which we associate a uniform density. Experimental results on synthetic data, as well as real world applications involving
visual scenes and object classification, indicates that the proposed approach was promising,
even though low-dimensional representation of the data was applied. In addition, it showed
the importance of embedding an outlier component to the proposed model. EM learning suffers
from significant drawbacks. In order to overcome those drawbacks, a learning approach using a
Bayesian framework is proposed as our second contribution. This learning is based on the estimation
of the parameters posteriors and by considering the prior knowledge about these parameters.
Calculation of the posterior distribution of each parameter in the model is done by using Markov
chain Monte Carlo (MCMC) simulation methods - namely, the Gibbs sampling and the Metropolis-
Hastings methods. The Bayesian Information Criterion (BIC) was used for model selection. The
proposed model was validated on object classification and forgery detection applications. For the
first two contributions, we developed a finite GID mixture. However, in the third contribution,
we propose an infinite GID mixture model. The proposed model simutaneously tackles the clustering
and feature selection problems. The proposed learning model is based on Gibbs sampling.
The effectiveness of the proposed method is shown using image categorization application. Our
last contribution in this thesis is another fully Bayesian approach for a finite GID mixture learning
model using the Reversible Jump Markov Chain Monte Carlo (RJMCMC) technique. The
proposed algorithm allows for the simultaneously handling of the model selection and parameter estimation for high dimensional data. The merits of this approach are investigated using synthetic
data, and data generated from a challenging namely object detection.


identifier: Garnet, Dustin  (2015) A Storied History of Art Education: The Art Department at Central Technical School, 1892-2014.  PhD thesis, Concordia University.

abstract:
A Storied History of Art Education: The Art Department at Central Technical School, 1892-2014
Dustin Garnet, Ph.D.
Concordia University, 2015

The Art Department at Central Technical School (CTS) in Toronto, Canada supports the
countries first and only specialized technical fine art program for adults and high school students.
My purpose in this research is to provide one version of this institution’s 122 year history
utilizing the lived experiences of the men and women who shared in its legacy. I explore how
stories as a form of historical research provide insights into the everyday lives and artistic culture
of CTS resulting in more localized and relational accounts of the past. Questions guiding this
study include: Who were the forces behind the growth of the CTS art program? What are the
factors that have helped sustain this publically funded institution? What were the major historical
events that shaped the history of CTS? And, why is the Art Department at CTS rarely mentioned
in written histories of Canadian art education?
From a theoretical perspective, my approach to new history(ies) has generated a socio-historical literary account of CTS as part of the field of art education, allowing me to construct
stories and emplot characters in ways that provide multiple forms and contexts to understand the
institution from more holistic perspectives. Through the methodological architecture of the
polyptych frame I have built a collection of historical stories that hinge together, but can be
separated and reconfigured to tell multiple stories from personal, external, and internal
perspectives. Stories are at the heart of my research and within them lies much more than
individual oral histories. The new history I construct speaks to a transgenerational artistic culture
iv
built on relationships and networks that directly contribute to shaping the visual culture of
Canada.
Invoking the use of stories as an aesthetic means of constructing history has permitted me
to expand on significant historical issues specifically addressing the domains of art, education,
social structure, and culture. In an effort to promote genealogical continuity rather than disparity
between historical realities and historical narratives I engaged in primary sources of information
that link five generations and identify four thematic threads including, identity politics,
institutional identity, school culture, social networks, that braid and create continuity over time.


identifier: DHAR, MOON MOON  (2015) Seismic Performance of Steel Plate Shear Walls Using Nonlinear Static Analysis.  Masters thesis, Concordia University.

abstract: Unstiffened steel plate shear wall (SPSW) is considered as a primary lateral load resisting system due to its significant post-buckling strength, high ductility, stable hysteretic behaviors and robust initial stiffness. Nonlinear seismic analysis can accurately estimate structural responses, however, the method is very time consuming and may not be suitable for regular engineering practice. On the other hand, traditional pushover analysis method does not consider contributions of higher modes to the structural responses and thus, often do not provide good estimation of seismic responses for taller buildings. Capacity-Spectrum Method (CSM) and modal pushover analysis (MPA) are two simple nonlinear static methods that have been proposed and recently used for seismic performance evaluation of few lateral load-resisting systems. This research further examines the applicability of CSM and MPA methods to assess seismic performance of steel plate shear walls. A nonlinear finite element model was developed and validated with experimental studies. Three different SPSWs (4-, 8-, and 15-storey) designed according to capacity design approach were analysed by subjecting the steel shear walls under artificial and real ground motions for Vancouver. The CSM and MPA procedures were applied to analyse the selected SPSWs and the results were compared with more accurate nonlinear seismic analysis results. It is observed that both CSM and MPA procedures can reasonably predict the peak roof displacements for low-rise SPSW buildings. In addition, MPA procedure, which includes contributions of higher modes when estimating seismic demands of buildings, provides better predictions of critical seismic response parameters for taller SPSWs.


identifier: Mistadi, Asma  (2015) Requirements of Modern Genome Browsers.  Masters thesis, Concordia University.

title: Requirements of Modern Genome Browsers

abstract:
Genome browsers are widely used tools for the visualization of a genome and related data.
The demands placed on genome browsers due to the size, variety, and complexity of the data produced by modern biotechnology is increasing.
These demands are poorly understood, and are not documented.
Our study is establishing and documenting a clear set of requirements for genome browsers.

Our study reviewed all widely used genome browsers, as well as notable research prototypes of genome browsers.
This involved a review of the literature, executing typical uses of the genome browsers, program comprehension, reverse engineering, and code analysis.

The key outcome of the study is a clear set of requirements in the form of a requirement document
which conforms to the IEEE Std 830-1998 Standard of a Software Requirement Specification.
This contains a domain model of concepts,
the functional requirements as use cases,
a definition of visualizations as metaphors, glyphs, or icons,
formal specification of the system in Z notation
and a specification of all widely used file formats.

Genome browsers share a set of basic features like display, scroll, zoom, and search.
However, they differ in their performance, maturity level and the implementation technologies.
Our requirements also document the major non-functional requirements.

The outcome of our study can be used in several ways:
it can be used as a guide for future developers of Genome Browsers;
it can form the basis of future enhancements of features in existing genome browsers;
and it can motivate the invention of new algorithms, data structures, or file formats for implementations.


identifier: Brnawy, Rahmah  (2015) An Efficient Technique for Clustering Data with Mixed Attribute Types.  Masters thesis, Concordia University.

abstract:
ABSTRACT

An Efficient Technique for Clustering Data with Mixed Attribute Types

Rahmah Brnawy
Clustering is a technique used to extract useful information and discover patterns from data. Existing clustering techniques have often focused on datasets with attributes that are either numeric or categorical but not both. The problem of clustering mixed numeric and categorical datasets has received increased attention more recently and a number of solutions have been proposed. In this research, we study these solutions and propose two clustering algorithms. The first algorithm that we present is called Cluc+, which extends and improves Cluc, an existing algorithm proposed for clustering pure categorical data. Using Cluc+, we then develop a new algorithm, called k-mixed for clustering data with mixed numeric and categorical attribute types. We conduct numerous experiments to evaluate the performance of our proposed algorithms using real-life benchmark datasets. Our results indicate increased efficiency and accuracy of the proposed solution techniques.


identifier: Gomaa, Hany  (2015) Impact and Shedding of Microdroplets on Hydrophilic and Superhydrophobic Surfaces.  PhD thesis, Concordia University.

abstract: The impact and shedding phenomena of water microdroplets on substrates with various wettabilitties are studied in this work. The analysis is aimed at illustrating the differences in behavior between micro, sub-millimeter and millimeter-sized droplets. This involved the evaluation of different parameters such as droplet maximum spreading, contact time, restitution coefficient as well as the critical air velocity for droplet shedding. The work focuses on the results obtained using a hydrophilic aluminum surface, which is the standard material used in aeronautics, and a superhydrophobic surface. After a comparative study on droplet size and surface wettability, the surface roughness effect on the impact of droplets is reported for both substrates. In addition, the adhesion of a sessile droplet on the two substrates is related to its corresponding shedding velocity. The analysis is considered a step forward in studying the behavior of cloud-sized (less than 100 µm) droplets especially on superhydrophobic surfaces. The first step of the current investigation was to design a dedicated test rig to work experimentally with microdroplets. The setup is developed to allow the microdroplet generator, camera, lighting and the designed shedding nozzle to work together without interfering with droplets imaging. Since the impact, deformation/bouncing, and shedding of the microdroplets occur in a matter of microseconds, high speed imaging is implemented. In addition, the MATLAB image processing toolbox is used to quantify the required parameters from the camera raw images by tracking their boundaries. The impact results show that the maximum spreading and recoiling of cloud-sized droplets on superhydrophobic surfaces are reduced when compared to sub-millimeter and millimeter sized droplets. This is depicted to the fact that the roughness of the superhydrophobic surface is in the same order of magnitude as the microdroplet size. Furthermore, the shedding tests illustrate that the smaller the droplet size, the higher the free stream incipient velocity needed for its shedding. The results also demonstrate the ease to remove impinged droplets from the superhydrophobic substrate when compared to the hydrophilic substrate, even at sub-zero temperatures.