identifier: Lei, Ming  (2014) Half-Duplex Relaying for the Multi-User Channel: Capacity Bounds, Fading Channel Performance and Asymptotical Behaviour.  PhD thesis, Concordia University.

abstract:
Multiple-input multiple-output (MIMO) scheme is able to improve the modern communications system performance in terms of increased throughput or reliability. As a virtually distributed antenna scheme, the relaying can enhance the communication system performance while there is no physical size limitation at the end user. Through decades, many relaying schemes have been extensively investigated for different channels. When the relay is close to the destination in a static channel and perfect channel state information (CSI) is available at the relay in a slow fading channel, the compress-and-forward (CF) scheme is often applied since it performs better than other relaying schemes. However, the CF scheme requires the relay to perform two-step operation (quantization and WZ binning), which increases the cost of implementing such scheme. In addition, having perfect CSI at the relay is not always possible in a wireless channel. To address these problems caused by the nature of the CF scheme, the generalized quantize-and-forward (GQF) scheme is proposed in this dissertation for the half-duplex (HD) multi-user channel.

In this dissertation, the first part focuses on studying the half-duplex (HD) relaying in the Multiple Access Relay Channel (MARC) and the Compound Multiple Access Channel with a Relay (cMACr). A GQF scheme has been proposed to establish the achievable rate regions. Such scheme is developed based on the variation of the Quantize-and-Forward (QF) scheme and single block with two slots coding structure. The achievable rates results obtained can also be considered as a significant extension of the achievable rate region of Half-Duplex Relay Channel (HDRC). Furthermore, the rate regions based on GQF scheme are extended to the Gaussian channel case. The scheme performance is shown through some numerical examples. In contrast to conventional Full-Duplex (FD) MARC and Interference Relay Channel (IRC) rate achieving schemes which apply the block Markov encoding and decoding in a large number of communication blocks, the GQF developed are based on the single block coding strategies, which are more suitable for the HD channels.

When the relay has no access to Channel State Information (CSI) of the relay-destination link, the GQF is implemented in the slow Rayleigh fading HD-MARC. Based on the achievable rates inequalities, the common outage probability and the expected sum rates are derived. Through numerical examples, we show that in the absence of CSI at the relay, the GQF scheme outperforms other relaying schemes. When the end users have different quality-of-service (QoS) requirements for slow fading channel, it is more precise to use the individual outage related parameters to quantify the scheme performance. The individual outage probability and total throughput are characterized for the HD-MARC. The numerical examples show that the outage probability of the individual users is lower than that of classic Compress-and-Forward (CF) scheme.

The Diversity Multiplexing Tradeoff (DMT) is often applied as a figure of merit for different communication schemes in the asymptotically high SNR slow fading channels. The CF scheme achieves the optimal DMT for high multiplexing gains when the CSI of the relay-destination (R-D) link is available at the relay. However, having the CSI of R-D link at relay is not always possible due to the practical considerations of the wireless system. In this dissertation, the DMT of the GQF scheme is derived without R-D link CSI at the relay. Moreover, the GQF scheme achieves the optimal DMT for the entire range of multiplexing gains.


identifier: Chen, Xi  (2015) Rethinking Firms’ Offshoring Strategy by Listening to the Voice of End Users: The Impact of Country-of-Origin Cues on Young Montréalers’ Product Evaluation.  Masters thesis, Concordia University.

type: Thesis NonPeerReviewed

abstract: Aiming to investigate the outcome of firms’ cross-border outsourcing practice from a bottom-up (customer-centered) approach, this research project leveraged on Mandler (1982, 1983)’s schema (in)congruity theory to examine young Montréalers’ reaction to products which had various design and manufacturing origins. With respect to scholars’ previous work, this research proposed that congruity between a product’s country of design and country of manufacture (Haubl & Elrod, 1999), consumer ethnocentric tendency (Shimp & Sharma, 1987) and product function (Voss, Spangenberg, & Grohmann, 2003; Wilcox, Kim, & Sen, 2009), respectively, would have positive impacts on consumers’ product evaluation. According to the questionnaire responses of 278 undergraduate students at Concordia University, no evidence could suggest that consumer evaluation of branded products were affected by the country-of-manufacture cue. Moreover, country-of-design effects and consumer ethnocentric tendency were showed to have different manifestations across product categories. Furthermore, product function was found to be not only positively related to consumer evaluation but also was an imperative mediator in consumers’ attitude toward, quality perception and purchase intention of branded products. Overall, the present study contributed to international business research and consumer behavior study by adding empirical evidence to support scholars’ viewpoint that country-of-origin effects on consumers’ product evaluation may be varied across product categories and by establishing a link between the construct of product function and country-of-origin effects. The importance of product function in end users’ evaluation of branded products shall also shed light on firms’ managerial implications.


identifier: Khayyat, Manal  (2015) An Intelligent Multi-Agent Based Model for Collaborative Logistics Planning.  Masters thesis, Concordia University.

abstract:
Efficient freight distribution is indispensable for sustaining customer demand in modern times. In recent years, there has been a steady growth in the use of information systems in the logistics domain towards facilitating an agile distribution process. This study investigates the problem of collaboration planning in logistics and proposes an agent based approach for better management of collaborative logistics.  Based on the approach, a decision support system is designed that utilizes RFID technology for ensuring inventory accuracy and monitoring carriers’ delivery movements.

The proposed approach involves three steps. In the first step, a conceptual framework is designed. Afterwards, a simulation agent based model is developed including six autonomous agents namely (RFIDG, Supplier, Retailer, Carrier, Network, and City Administrator) interacting with each other, as well as, with the surrounding environment. In the second step, game theory is utilized to study and analyze suppliers’ collaboration and carriers’ collaboration behavior in detail. Modeled games are solved using Nash Equilibrium. Finally, correctness of the games is verified by formulating them mathematically. Developed optimization equations are fundamental to the operations research field. They employ the simplex and goal algorithms of linear programming.

Results prove that there are plethora of advantages such as automatism and real time response, cost reduction, increased suppliers’ profits, time management, and a collaborative framework for implementing the proposed agent based model where suppliers, retailers, and carriers will receive immediate benefits. Major contributions of the thesis stems from considering future technologies such as RFID and agent oriented strategies to provide fast quality services to customers.


identifier: Karout, Racha  (2015) A DMAIC Framework for Improving Software Quality in Organizations: Case Study at RK Company.  Masters thesis, Concordia University.

abstract:
Managing quality is a vital aspect in software development world, especially in the current business competition for fast delivery of feature rich products with high quality. For an organization to meet its intended level of excellence in order to ensure its success, a culture of quality should be built where every individual is responsible of quality and not just the software testing team. However, delivering software products with very few bugs is a challenging constraint that is usually sacrificed in order for a company to meet other management constraints such as cost, scope and scheduling.
The purpose of this thesis is to apply six sigma DMAIC framework on 'RK’ company (name anonymized) in order to help software organizations focus on improving the quality of their software products. Different phases of DMAIC methodology are applied to one of the largest software applications for ‘RK’ company where critical to quality aspects were identified, production bugs were classified and measured, the causes of the large number of production bugs were specified leading to different improvement suggestions. Several metrics were proposed to help ‘RK’ company control its software development process to ensure the success of the project under study.


identifier: Alcolado, Gillian M.  (2014) Beliefs about Memory in Compulsive Checking and Obsessive-Compulsive Disorder: Assessment and Intervention.  PhD thesis, Concordia University.

abstract: Checking is one of the most common compulsions in obsessive-compulsive disorder (OCD).  Some have suggested that individuals who check repeatedly may have memory deficits, but findings of memory-related investigations have been inconsistent.  In contrast, beliefs about memory have been shown to relate closely to checking behaviour.  Thus, it is possible that mixed findings regarding the presence of memory deficits in association with OCD may be related to maladaptive beliefs influencing performance.  Currently no measure exists to assess these beliefs, nor does an intervention to improve them, despite the existence of such measures and interventions for other known maladaptive beliefs central to OCD.  The present studies were thus designed to measure and examine the relationships between beliefs about memory, actual memory performance, and checking compulsions.  The first study encompassed the development of the Beliefs About Memory Inventory (BAMI) to assess maladaptive beliefs that individuals hold about their memory.  Non-clinical (N = 697) and clinical (N = 24) participants completed the candidate items for the BAMI along with other relevant questionnaires to determine its psychometric properties.  Results showed that the psychometrically-sound measure is comprised of two factors: beliefs about memory ability, and beliefs about the importance of memory.  Furthermore, the BAMI was able to predict checking symptoms over and above existing belief domains known to be relevant to OCD.  The second study examined whether a brief cognitive intervention designed to improve beliefs about memory in a sample of compulsive checkers could decrease checking and increase memory performance.  Individuals with OCD (N = 24) who exhibited clinical levels of checking symptoms monitored their checking behaviour over the course of a two-session intervention.  Half were randomly assigned to the treatment condition, while the other half were randomly assigned to a waitlist control condition.  Participants also completed neuropsychological tests pre- and post-treatment/waitlist.  Results demonstrated that compared to those in the waitlist condition, individuals in the treatment condition decreased their maladaptive beliefs about memory, checking behaviour, and symptoms, while increasing their memory performance.  The results of these studies are discussed in the context of implications for cognitive-behavioural theories of and interventions for OCD.


identifier: Singh, Amardeep  (2014) Analysis of Leaky Wave Antennas Using the Matrix Pencil Method.  Masters thesis, Concordia University.

abstract:
The leaky-wave antenna (LWA) is a traveling wave antenna that uses a fast wave
as the main radiating mechanism, where the fast wave is radiating continuously along
the structure. Depending on the length of the antenna, some part of the fast wave
gets reflected from the end and causes another beam in the opposite direction. The
effects of the reflected fast wave on the radiation pattern can be analyzed if the
reflection coefficient at the end of the antenna is known, which can be obtained from
the complex amplitude and propagation constants associated with the fast waves.
Even the radiation pattern of a LWA can be obtained using the reflection coefficient
and propagation constants.
Closed top guiding structures, a dielectric slab waveguide, 2-D LWAs and 3-D
LWAs are modeled in a commercial full wave MoM solver, FEKO. The near-field
samples are calculated along the structure. For these types of structures, the total
near field can be expressed as a sum of complex exponentials. The matrix pencil
method (MPM) is a most accurate and efficient linear technique to approximate a
function by a sum of complex exponentials. The exponential components from the
total near field use the complex propagation constants inside the structure, which are
calculated using the MPM. The MPM extracted amplitude and phase components
are used to calculate the reflection coefficients of the structures and radiation patterns
of the LWAs.
The accuracy of this approach is verified using various open and closed guiding
structures in 2-D and 3-D, and by comparing the results with available numerical and
experimental results.


identifier: Chen, Yiheng  (2015) Survivable Virtual Network Redesign and Embedding in Cloud Data Center Networks.  Masters thesis, Concordia University.

abstract:
Today, the cloud computing paradigm enables multiple virtualized services to co-
exist on the same physical machine and share the same physical resources, hard-
ware, as well as energy consumption expenses. To allow cloud customers migrate
their services on to the cloud side, the Infrastructure Provider (InP) or cloud
data centre operator provisions to its tenants virtual networks (VNs) to host their
services. Virtual Networks can be thought of as segmenting the physical net-
work and its resources, and such VN requests (or tenants) need to be mapped
onto the substrate network and provisioned with sufficient physical resources as
per the users’ requirements. With this emerging computing paradigm, cloud cus-
tomers may demand to have highly reliable services for the hosted applications;
however, failures often happen unexpectedly in data-centers, interrupting critical
cloud services. Consequently, VN or cloud services are provisioned with redun-
dant resources to achieve the demanded level of service reliability. To maintain
a profitable operation of their network and resources, and thus achieve increased
long term revenues, cloud network operators often rely on optimizing the map-
ping of reliable cloud services. Such problem is referred to as in the literature as
“Survivable Virtual Network Embedding (SVNE) ” problem. In this thesis, the
survivable VN embedding problem is studied and a novel cost-efficient Survivable
Virtual Network Redesign algorithm is carefully designed, presented, and evalu-
ated. Subsequently, we distinguish between the communication services provided
by the cloud provider and study the problem of survivable embedding of multicast
services; we formally model the problem, and present two algorithms to reactively
maintain multicast trees in cloud data centers upon failures.


identifier: Chtchetinina, Anna  (2015) Experimental Investigation of Jets through a Model Mitral Valve with Different Leaflet Suture Configurations.  Masters thesis, Concordia University.

abstract:
This thesis presents an experimental study of jets emitted from flexible orifices of different configurations and is aimed at understanding the effects of a repair procedure for a malfunctioning mitral valve known as Edge-to-Edge repair. This study looks at simplified orifice geometries referred to as no-clip, middle-clip, and side-clip configurations. The flow is generated through a piston-cylinder setup. Time-resolved Particle Image Velocimetry (TR-PIV) is used for flow measurements. The velocity data is extracted using a commercial software, and is then processed with custom codes to analyze and reveal different flow characteristic features once the jets have interacted.
The results were obtained from analysing the average velocity fields, and it was noted that while the no-clip configuration would only be affected by the boundary layer roll-up produced at the exit of the orifice, the middle-clip configuration would strongly resemble the behaviour of two closely-spaced parallel jets. The two velocity profiles would gradually merge into one “plug-like” profile spreading radially. For the side-clip configuration, it was noted that while the proportional difference between the two velocity maxima did not exhibit dependence on the Reynolds number, the difference would be affected by the entrainment of the secondary jet into the primary jet. As a result, maximum velocity of the side-clip configuration’s primary jet at the end of the tested region was equivalent to that of the overall middle-clip velocity maximum. The entrainment of the secondary jet also resulted in the profile shifting in the direction of the primary jet. From the Proper Orthogonal Decomposition of the flow data, it was concluded that the highest energy consumption for the middle and side-clip configurations was attained through the first two modes, whose proportional difference is positively correlated with the piston stroke used. Reynolds Shear Stresses, as well as Turbulent Kinetic Energy is also assessed in order to have insight into the turbulent quantities affecting the hemodynamics. Although the side-clip configuration was discovered to be dominated by higher Reynolds Shear Stresses, it is believed that the longer duration of such stresses, combined with higher energy fluctuations of the Turbulent Kinetic Energy may produce more blood damage in the middle-clip configuration setting.


identifier: Jiang, Yingru  (2015) Noise or Reality: An Empirical Study of Target Pre-bid Returns.  Masters thesis, Concordia University.

abstract: Providing new evidence derived from a large sample simulation using US exchange-listed firms from 1990 to 2012, this paper contributes to the discussion about 1) the magnitude of target pre-bid abnormal returns (conventionally called the “run-ups”) and 2) the substitution and mark-up pricing relation between pre-bid run-ups and post-bid mark-ups of M&A targets. As random simulation represents the normal scenario (i.e. probability of M&A announcement is unpredictable), we should consider empirically derived critical values of simulation run-ups as the new benchmarks when testing the significance of the target’s pre-bid abnormal return. The fact that only 13% of M&A run-ups could be recognized as abnormal when compared to new benchmarks raises doubts about the traditional approach. In the examination of the relationship between run-ups and mark-ups, a 0.4674 coefficient in the regression of mark-up on run-up using pure random sample makes significant contribution to the debate upon substitution and mark-up pricing hypotheses. If we take 0.4674 as a baseline, the coefficient of the regression is supposed to be smaller if substitution hypothesis outweighs mark-up pricing hypothesis, otherwise this coefficient will be larger than 0.4674. Although the conclusion is still open, findings in this paper and in Schwert (1996) actually tend to support the substitution hypothesis instead of mark-up pricing hypothesis, suggesting pre-bid run-ups do not necessarily cause a higher bidding price for the bidders.


identifier: McDonagh, Patrick  (1998) The Image of Idiocy in Nineteenth Century England: A history of cultural representations of intellectual disability.  PhD thesis, Concordia University.

abstract: Over the nineteenth century, the popular and the scientific understanding of idiocy changed in conjunction with shifts in social concerns and the emergence of new discourses. An examination of representations of idiocy over the century foregrounds the manner in which the condition was given shape and meaning. The dissertation traces the history of the idea of intellectual disability in England from the start of the nineteenth century up to the initial articulation of eugenics, and argues that the idea of intellectual disability acquired new significance in the Victorian era, eventually stabilizing somewhat with the notion of the idiot as degenerate. Political, gender, economic, religious, literary and scientific discourses interact to weave a notion of what intellectual disability means and how it should be interpreted. This dissertation examines the ways that idiocy is constructed by these discourses, and to what ideological purpose, by reading critically texts involved in the construction of the notion. These texts include Wordsworth’s “The Idiot Boy,” Dickens’ Barnaby Rudge, Scott’s Waverley, and Gaskell’s “Half a Life-time Ago,” among other literary works, as well as medical, scientific and sociological writings. The dissertation is organized thematically and, for the most part, chronologically to sketch out a cultural history of the idea of idiocy, with an emphasis on delineating the factors that shaped perceptions (the idiot as holy fool, as innocent, or as degenerate), as well as on the ideological significance of the notion of idiocy. Throughout the dissertation, special emphasis is placed on the relation of intellectual disability to gender notions, and the varying interpretations of the significance of intellectual disability when associated with men or women.


identifier: El-Abbasy, Mohammed Saeed Khalil  (2015) Multi-Objective Multi-Project Construction Scheduling Optimization.  PhD thesis, Concordia University.

abstract: In construction industry, contractors usually manage and execute multiple projects simultaneously within their portfolio. This involves sharing of limited resources such as funds, equipment, manpower, and others among different projects, which increases the complexity of the scheduling process. The allocation of scarce resources then becomes a major objective of the problem and several compromises should be made to solve the problem to the desired level of optimality. In such cases, contractors are generally concerned with optimizing a number of different objectives, often conflicting among each other. Thus, the main objective of this research is to develop a multi-objective scheduling optimization model for multiple construction projects considering both financial and resource aspects under a single platform. The model aims to help contractors in devising schedules that obtain optimal/near optimal tradeoffs between different projects’ objectives, namely: duration of multiple projects, total cost, financing cost, maximum required credit, profit, and resource fluctuations. Moreover, the model offers the flexibility in selecting the desired set of objectives to be optimized together. Three management models are built in order to achieve the main objective which involves the development of: (1) a scheduling model that establishes optimal/near optimal schedules for construction projects; (2) a resource model to calculate the resource fluctuations and maximum daily resource demand; and (3) a cash flow model to calculate projects’ financial parameters. The three management models are linked with the designed optimization model, which consequently performs operations of the elitist non-dominated sorting genetic algorithm (NSGA-II) technique, in three main phases: (1) population initialization; (2) fitness evaluation; and (3) generation evolution. The optimization model is implemented and tested using different case studies of different project sizes obtained from literature. Finally, an automated tool using C# language is built with a friendly graphical user interface to facilitate solving multi-objective scheduling optimization problems for contractors and practitioners.


identifier: Alhirabi, Nada  (2015) A Visual Spreadsheet using HTML5 for Whole Genome Display.  Masters thesis, Concordia University.

abstract:
Modern sequencing technology has enabled the cheap, rapid production of
whole genomes. There is a need for visualization tools to show the data
collected about a whole genome such as genes, proteins, annotations, and
expression data. Many common approaches are developed such as the genome browser where
sequence features are displayed as visual elements in tracks and features are
aligned with their genome coordinates, visual networks where the data elements represented as nodes and relationship as edges, and traditional spreadsheet where each row
captures the information about a gene/genome where the information is textual in
nature, such as identifiers, descriptions, or sequences.
Our study is focusing in the last approach with introducing some advanced features.

To build the system, the common used similar systems are reviewed, and during the implementation some software artifacts are reused such as reusing some JavaScript libraries to reduce the complexity of software development.
Generally, an incremental method is used to develop the webpage starting from collecting the data from AspGD database, analyzing them, coding then testing them once at time.
Our research group studies fungal genomes, so the spreadsheets are tested by displaying each of the Aspergilli genomes in the AspGD database (www.aspgd.org).

We have developed CGene and CGenome, pronounced See-Gene and See-Genome respectively, as a HTML5 web-based spreadsheets that can incorporate visual displays, as well as text, within the spreadsheet cells. Current displays use Scalable Vector Graphics (SVG) to present these spreadsheets which are generated from standard GFF3 files, standard output files from InterProScan, aspgd files from AspGD Gene Ontology Annotations File, and Chromosomal Feature File. All these files are analyzed to present them in a visual way that requires less effort to understand.

The main aim of our study is to take the advantages of the ability of humans to recognize patterns. The user can see the gene/genomes of interest as row-by-row of visualization. This can play powerful roll to ease the understanding of quantitive data by replacing them by graphical figures that make the comparison easier.


identifier: Bilhete, Caroline  (2015) The effect of habitat complexity on Atlantic salmon behaviour.  Masters thesis, Concordia University.

abstract: An increase in habitat complexity is thought to decrease visibility and the territory size of visually-oriented animals. Hence, the addition of physical structure has been viewed as a restoration technique, particularly in streams, to increase the density of target species. However, a decrease in territory size may have a negative effect on the fitness of individual organisms. This project is a first attempt to evaluate the effects of habitat structure on the behaviour and growth rate of wild young-of-the-year (YOY) Atlantic salmon. Fish were exposed to one of two habitat treatments in mesh enclosures in Catamaran Brook, New Brunswick: a fine gravel substrate (low complexity) or a fine gravel substrate with boulders added (high complexity). Wild-caught individuals were tagged, weighed and measured before being stocked at densities of ~ 1m2 for seven day trials. Fish from high complexity environments exhibited a decrease in foraging rate, frequency of aggression, territory size compared to their counterparts from low complexity environments. Specific growth rate, however, did not differ significantly between treatments. While the addition of structure to a habitat may be beneficial at the population level in terms of an increase in population density, our results suggest that individual fish may pay a cost in terms of a decrease in foraging rate and territory size in these environments. Further research is needed to evaluate the costs and benefits of adding structure to improve the habitat quality for stream salmonids.


identifier: Yuan, Yuan  (2014) Nonlinear Optimization for Managing Occupational Exposure Risks in the Nanomaterial Manufacturing Workplace under Uncertainty.  Masters thesis, Concordia University.

abstract:
Critical environmental and human health concerns are associated with the rapidly growing fields of nanotechnology and Engineered nanomaterials (ENMs). The main risk arises from occupational exposure via chronic inhalation of nanoparticles. This research presents a fuzzy chance-constrained nonlinear programming (FCCNLP) optimization approach, which is developed to maximize the nanomaterial production and minimize the risks of workplace exposure to ENMs. The FCCNLP method integrates fuzzy mathematical programming (FMP) and chance-constrained programming (CCP) into nonlinear programming (NLP) optimization framework, and could be used to deal with uncertainties expressed as not only probability distributions and fuzzy values associated with components of constraints but ambiguity of the objective function as well.
     The FCCNLP method was examined through a single-walled carbon nanotube (SWNT) manufacturing process. Solutions of the compromise decision alternatives associated with different risk levels of relaxed constraint violations were obtained. This study confirmed that a high level control strategy through strict occupational exposure limits (OELs) combined with a high enforcement of OELs would lower the nanomaterial exposure risks to workers. The related cost and nanomaterial production have also been optimized for different operational scenarios under multi-layer system uncertainties. The results were helpful for decision makers to identify desirable schemes under uncertainties to maximize the economic benefits and ensure workplace safety through minimizing the nanomaterial-related health risks.  The developed technology has technical novelty to help finding cost-effective measures for the sustainable development of nanotechnology.


identifier: Choudhury, Abhijit  (2015) Three-level neutral point-clamped (NPC) traction inverter drive for electric vehicles.  PhD thesis, Concordia University.

abstract:
The motivation of this project was to develop a three level neutral point clamped (NPC) traction inverter for a permanent magnet synchronous machine drive.  The three-level inverter helps to reduce the total inverter losses at higher switching frequencies, compared to a two-level inverter for electric vehicle applications. The three-level inverter has also more power switches compared to the two-level inverter. This helps to reduce the voltage stress across the switches and the machine winding. In addition, it also allows an increase in the DC-link voltage, which in turn helps to reduce the DC-link current, phase conductor size and the associated losses. Moreover, at higher DC-bus voltages the power switches will have lower thermal stress when compared to the 2-level. However, the NPC inverter topologies have an inherent problem of DC-link voltage balancing.
In the initial part of this thesis, a novel space vector based DC-link voltage balancing strategy is proposed. This strategy can keep the two DC-link capacitor voltages balanced during transient changes in both speed and torque. The performance of the three-level inverter system is then compared with a two-level inverter based drive to validate its performance improvement. The results showed a significant reduction in total voltage and current harmonic distortions, reduced total inverter losses (by 2/3rd) and was even was able to keep the neutral point fluctuation low at all operating load power factor conditions.
The second motivation of this thesis was to reduce the computational time in the real-time implementation of the control logic. For this purpose, a modified carrier and hybrid-carrier based PWM strategy was proposed, which also kept the DC-link capacitor voltages balanced. The modified carrier based strategy was able to reduce the switching losses compared to the conventional strategies, while the hybrid-carrier based strategy kept the advantages of both carrier and the space vector techniques.
Finally, a performance comparison study was carried out to compare the total harmonic distortion, switching loss distribution, and total inverter loss of all the four proposed strategies.


identifier: Chaouch, Donia  (2015) Formalization of Continuous Time Markov Chains with Applications in Queueing Theory.  Masters thesis, Concordia University.

abstract:
The performance analysis of engineering systems have become very critical due to their usage in safety and mission critical domains such as military and biomedical devices. Such an analysis is often carried out based on the Markovian (or Markov Chains based) models of underlying software and hardware components. Furthermore, some important properties can only be captured by queueing theory which involves Markov Chains with continuous time behavior. Classically, the analysis of such models has been performed using paper-and-pencil based proofs and computer simulation, both of which cannot provide perfectly accurate results due to the error-prone nature of manual proofs and the non-exhaustive nature of simulation. Recently, model checking based formal methods have also been used to analyze Markovian and queuing systems. However, such an approach is only applicable for small systems and cannot certify generic properties due to the sate-space explosion problem.
In this thesis, we propose to use higher-order-logic theorem proving as a complementary approach to conduct the formal analysis of queueing systems. To this aim, we present the higher-order-logic formalization of the Poisson process which is the foremost step to model queueing systems. We also verify some of its classical properties such as exponentially distributed inter-arrival time, memoryless property and
independent and stationary increments. Moreover, we used the formalization of the Poisson process to model and verify the error probability of a generic optical communication system. Then we present the formalization of Continuous-Time Markov Chains along with the Birth-Death process. Lastly, we demonstrate the utilization of our developed infrastructure by presenting the formalization of an M/M/1 queue which is widely used to model telecommunication systems. We also formally verified the generic result about the average waiting time for any given queue.


identifier: Dejam, Bardia  (2015) Design and Simulation of RFID-Enabled Aircraft Reverse Logistics Network via Agent-Based Modeling.  Masters thesis, Concordia University.

abstract:
Reverse Logistics (RL) has become increasingly popular in different industries especially aerospace industry over the past decade due to the fact that RL can be a profitable and sustainable business strategy for many organizations. However, executing and fulfilling an efficient recovery network needs constructing appropriate logistics system for flows of new, used, and recovered products.
On the other hand, successful RL network requires a reliable monitoring and control system. A key factor for the success and effectiveness of RL system is to conduct real-time monitoring system such as radio frequency identification (RFID) technology. The RFID system can evaluate and analyze RL performance timely so that in the case of deviation in any areas of RL, the appropriate corrective actions can be taken in a quick manner. An automated data capturing system like RFID and computer simulation techniques such as agent-based (AB), system dynamic (SD) and discrete event (DE) provide a reliable platform for effective RL tracking and control, as they can respectively decrease the time needed to obtain data and simulate various scenarios for suitable best corrective actions. The functionality of the RL system can be noticeably elevated by integrating these two systems and techniques. Besides, each computer simulation approach has its own benefits for understanding the RL network from different aspects. Therefore, in this study, after designing and constructing the RL system through the real case study from Bell Helicopter Company with the aid of unified modeling language (UML), three simulation techniques were proposed for the model. Afterwards the results of all three simulation approaches (AB, SD and DE) were compared with considering two scenarios of RL RFID-enabled and RL without RFID.  The computer simulation models were developed using “AnyLogic 7.1” software.
The results of the research present that with exploiting RFID technology, the total disassembly time of a single helicopter was decreased. The comparison of all three simulation methods was performed as well.

Keywords: Reverse logistics (RL), RFID, aerospace industry, agent-based simulation, system dynamic simulation, discrete event simulation, AnyLogic


identifier: Sahagún Sánchez, Verónica  (2015) Weaving Mestiza Geographies:An A/r/tographic Allegory on Cultural Identity Through the Lens of Vernacular Textile Traditions.  PhD thesis, Concordia University.

abstract:
In Weaving Mestiza Geographies, I use Mexican vernacular textile traditions as the foundation for a self-study focused on my cultural identity. This project departs from my creative pratice and asks: In what ways may the aesthetics of Mexican vernacular textile traditions influence my art making and my teaching as a visual artist trained within Western educational contexts? At a theoretical level, I draw on aspects of feminist epistemologies and geographies, and Mexican history as well as postcolonial theory. I work with a/r/tography, a research methodology that weaves the practices of the artist/researcher/teacher together through a complementary dialogue between image (art) and text (writing). Based on the idea of allegory as a practice that uses symbols to reveal hidden meanings, combining visual and text-based symbols allows me to develop a decolonizing praxis consisting of (un)hiding the Indigenous legacies that form my mestiza (or mixed) identity.
Weaving Mestiza Geographies also addresses issues that relate to contemporary craft theory and practice. I approach the craft object as an embodiment of local, communal, familial, and cultural histories as well as of personal memories. In other words, vernacular textiles become gateways for me to review my relationship to people and places in Central México. In the studio, I reflect on the implications of merging practices of the handmade (weaving, stitching, collaging, assembling) with digital media (photography, digital imaging, printing, and stop motion animation). The knowledge gained when fusing these two ways of working supports the design of three pedagogical strategies (life crafting, digital-craft, and subversive cartography); these are conceived as third spaces in which groups that may have experienced some form of marginalization can access educational experiences that are reflective of their cultural backgrounds and personal histories. Future paths of inquiry will involve participatory art and a/r/tographic action research methodologies with applications in community art and social research that address the identity and body politics framing textile making and other craft practices within the contemporary global economy.


identifier: Parambath Mohan, Rahul  (2015) Investigation of Intra/ply Shear Behavior of Out-of-Autoclave Carbon/Epoxy Prepreg.  Masters thesis, Concordia University.

abstract:
The forming of a composite part without defects has been a challenging issue till date due to the complexity of the process. Lack of knowledge on the in- plane shear behavior of the composite during forming has always served as the prime reason for the defects. Still, a sound knowledge of diverse phenomena which make these flaws such as wrinkling, would help to optimize the performance. In addition, the possibility to form a composite part from out-of-autoclave prepreg without any defect would further enhance the process due to the cost reduction caused by eliminating the autoclave.
The work presented herein aims to investigate the intra-ply shear behavior of out- of- autoclave carbon epoxy thermoset prepreg and its effect on wrinkling using the picture frame and bias extension tests. Tests will be performed at varying temperatures and displacement rates in order to determine their contribution on deformability of the fabric. Digital image correlation was applied onto the set-up to take sequential images at various stages of deformation and capture the onset of wrinkling. Microstructural analysis was performed in order to observe the change in tow geometry throughout the shear deformation. In addition, the uni-directional and woven prepreg (8- harness and 5- harness) were compared to the scale of their deformability to determine the material which favors the forming the most. Finally, based on the response of the operating temperature (resin viscosity), displacement rate and layer counts (layer interactions) on the onset of wrinkling, an optimization method was generated using the Taguchi and Analysis of Variance technique to determine the parameter which influences, wrinkling the most.


identifier: Pourtolami, Nima  (2015) Higgs Phenomenology in Warped Extra Dimensions.  PhD thesis, Concordia University.

abstract:
This thesis is a study on phenomenology of beyond the Standard Model in the context of warped extra-dimensional (Randall-Sundrum) models. These models, through introducing a large extra space dimension along which the standard model fields can propagate, can address the hierarchy between the Plank and weak scales, provided that the geometry is suitably curved along the fifth dimension and the extra dimension is stabilized. The space-time background that is considered in this thesis is mainly in a more general form which is modified from the usual AdS5. This modification can alleviate considerably the bounds coming from precision electroweak tests and flavor physics. Of course, the usual AdS5 geometry is a special case and can be reproduced by taking the correct limits.
In this thesis, we mainly consider the case where the extra dimension is bounded by two stabilized hard walls (branes) at the TeV (IR brane) and Plank (UV brane) scales. Also our principal consideration will be the case when all the standard model fields propagate in the bulk, although we comment on the case where only the Higgs is localized on the TeV brane.
Within this context, after a broad review of the main concepts, we first address the phenomenology of a bulk scalar Higgs boson, and calculate its production cross section at the LHC as well as its tree-level effects on mediating flavor changing neutral currents. We perform the calculations based on two different approaches. First, we compute our predictions analytically by considering all the degrees of freedom emerging from the dimensional reduction (the infinite tower of Kaluza-Klein modes (KK)). In the second approach, we perform our calculations numerically by considering only the effects caused by the first few KK modes, present in the 4-dimensional effective theory. In the case of a Higgs leaking far from the brane, both approaches give the same predictions as the effects of the heavier KK modes decouple. However, as the Higgs boson is pushed towards the TeV brane, the two approaches seem to be equivalent only when one includes heavier and heavier degrees of freedom (which do not seem to decouple). To reconcile these results it is necessary to introduce a type of higher derivative operator which essentially encodes the effects of integrating out the heavy KK modes and dresses the brane Higgs so that it looks just like a bulk Higgs.
Secondly we calculate the production rate of the Higgs boson at the LHC in the context of general 5D warped scenarios, and show that it is generically consistent with the current experimental results from the LHC for Kaluza-Klein (KK) masses as low as 2 TeV, unlike in pure AdS5 scenarios, where for the same masses, the Higgs production typically receives corrections too large to be consistent with LHC data. Thus the new pressure on warped models arising from LHC Higgs data is also alleviated in modified AdS5 warped scenarios.
And finally we show that in these backgrounds, high energy flavor symmetries are inherent. When these high energy symmetries are broken at lower energies, they produce the Standard Model (SM) structure including the neutrinos. This feature is completely general and depends neither on the details of the background metric, as long as it produces the required hierarchy, nor on the exact form of the symmetry, as long as it produces the required PMNS matrix. The reason for this phenomena is inherent in the structure of the exponential hierarchy factors of warped extra-dimension scenarios with bulk matter fields. While these factors produce the hierarchy of masses in quarks and charged lepton sectors, they flatten in to a plateau at larger c-parameters to accommodate the neutrinos. In the case of the quark and charged lepton sectors, these exponential hierarchy factors “wash off” the structure of the order one five dimensional Yukawa couplings, and naturally produce the hierarchical masses and the CKM matrix, while for the neutrinos sector, while for the neutrinos, the structure of the high energy symmetries are preserved to attain the SM.


identifier: Bethel, Edward Clement  (2015) A Systematic Review of One-to-One Access to Laptop Computing in K-12 Classrooms: An Investigation of Factors that Influence Program Impact.  PhD thesis, Concordia University.

abstract: In 2005, Nicholas Negroponte stepped onto the stage at TED and challenged the audience: “What would happen if we gave every student a laptop computer?” Ten years later, and twenty-five years after the first laptop program, this dissertation attempts to answer that question using two systematic review procedures, case survey analysis and mixed effects meta-analysis. Literature searches and review resulted in 162 primary studies being included in the case survey of which 88 studies yielding 231 effect sizes and representing approximately 116,150 participants, were selected for the meta-analysis. The case survey analysis revealed that typically, programs were co-educational, involving public middle schools, and conducted at the board or district levels. Program theories, whether stated or inferred clustered around three main themes: technology-enhanced environments, technology-enhanced instruction, and computers as mind tools or learning tools. Program goals were numerous and varied, but centered on technology use and proficiency, achievement, questions of technology equity, and improved instruction. The meta-analysis revealed that one-to-one computing had an impact on five of the six outcomes tested: technology use (mean effect size 0.53), technology proficiency (0.29), student achievement (0.23), student engagement (0.15), and student satisfaction (0.26). Attendance was not significant (0.00).  The general effects were moderated in expected and unexpected ways – technology use was moderated by program theory and year, technology proficiency was moderated by technology use and duration, and achievement was moderated by program size, participant age, program year, technology integration, duration, and teacher-centered instruction. Explanations were proposed for these findings, and new directions for future research outlined.


identifier: Brunet, Stephanie  (2015) Functional studies of yeast mutants reveal mechanisms for TRAPP‐complex integrity.  PhD thesis, Concordia University.

abstract:
Functional studies of yeast mutants reveal mechanisms for TRAPP-complex integrity

Stephanie Brunet, PhD
Concordia University, 2015

Proteins and lipids are packaged into membrane bound vesicles and transported
throughout the cell in a highly regulated process called membrane trafficking. Several
categories of proteins including tethering factors, cooperate to ensure fidelity in this
process that function as a physical a link between a vesicle and the correct target
membrane. The transport protein particle (TRAPP) complex is a multisubunit tethering
complex that has been well characterized in yeast and is highly conserved in mammals. In
yeast, three isoforms of the complex (TRAPPI, TRAPPII and TRAPPIII) have been described
each acting in different membrane trafficking pathways. My research has focused on
studying yeast TRAPP mutants to understand how specific subunits contribute to TRAPPcomplex
integrity and how each complex regulates distinct membrane trafficking
pathways.
Several mutations in the human TRAPPC2 gene including a missense mutation of a
highly‐conserved aspartic acid residue (TRAPPC2D47Y), are linked to the skeletal disorder
spondyloepiphyseal dysplasia tarda (SEDT), Chapter 2 discusses how the analogous
mutation in the yeast homologue, TRS20, destabilizes the TRAPPIII complex and disrupts
TRAPPIII‐regulated membrane trafficking pathways, providing insight into the etiology of
SEDT.
Chapter 3 of this thesis describes a mutational study that I conducted on the
essential yeast TRAPP subunit, Trs23p. When a non‐essential Saccharomycotina‐specific
(SMS) domain within this protein is deleted, TRAPPI, the smallest of the complexes, is
destabilized however processes regulated by TRAPPI are not compromised. TRAPPII and
TRAPPIII contain all the subunits of the smaller TRAPPI complex and I propose that
TRAPPI is a fragment or assembly intermediate of the larger complexes.
Finally, in Chapter 4 I present evidence for a direct interaction between the TRAPPII
complex and Gyp6p, a GTPase accelerating protein (GAP) for the small Rab GTPase Ypt6p.
In mutants that destabilize the TRAPPII complex this interaction is disrupted and Ypt6p
localization to the late Golgi compartment is increased relative to wild type. Together these
results indicate that the interaction between TRAPPII and Gyp6p is important for
regulating the dynamic distribution of Ypt6p within the cell.


identifier: Kalra, Mayank  (2014) Development and Assessment of a Coupling Force Measurement System Applied to Stationary and Vibrating Tool Handles.  Masters thesis, Concordia University.

abstract:
Exposure to hand-transmitted vibration (HTV) arising from operating hand-held power tools has been associated with various health consequences. The magnitude of HTV is strongly affected by the hand-handle interface coupling forces, handle geometry and gripping method apart. Assessment of the HTV exposure currently does not incorporate the impact of coupling forces exerted at the hand-handle interface, mostly due to lack of reliable measurement methods for hand-handle interface forces. This dissertation seeks to develop a low cost hand-handle coupling force measurement system and methods for quantifying the hand grip and push forces applied to the tool handles.
A hand-handle interface force measurement system was developed using flexible force sensing resistors (FlexiForce). The static properties of the sensors were thoroughly characterized in terms of linearity, hysteresis and repeatability. Moreover, the sensors’ output characteristics were observed by considering the effect of positioning, area and flexibility of the loading medium used to transmit the applied forces. Five different cylindrical and elliptical instrumented handles were subsequently chosen to observe the input-output characteristics of the sensors under stationary and vibrating conditions. The measurements under static and dynamic conditions revealed good linearity and repeatability of the sensors, and affirmed their feasibility for accurate estimations of the hand grip and push forces. The sensors’ outputs also showed strong dependence on the loading medium’s area, position and flexibility as well as the length of the sensor suggesting the need for individual sensor calibration, which was noted as the primary limitation of the system.
The effectiveness of the measurement system was further explored through measurements of hand forces on a percussion tool handle and biodynamic responses of the human hand-arm system. The measurement system provided reasonably good estimations of the hand grip and push forces when applied to the percussion tool handle under both stationary as well as vibration conditions. The biodynamic impedance responses measured with six subjects showed trends similar to the reference response. However, a compensation function was necessary and subsequently proposed to account for the limited bandwidth of the sensors.


identifier: Guèvremont, Amélie  (2015) Brand authenticity: definition, measurement, antecedents, and consequences.  PhD thesis, Concordia University.

abstract:
Consumers are increasingly demanding authentic products, experiences, and brands. Although brand authenticity is gaining interest from academics and practitioners, research is lacking regarding the nature of an authentic brand and the implications of brand authenticity. This dissertation focuses on conceptualizing brand authenticity and understanding its antecedents and consequences in the marketplace.
The first objective of this research is to develop and validate a reliable and parsimonious scale measuring brand authenticity (chapter 2). An extensive literature review across domains is followed by a qualitative study in which fourteen in-depth interviews are conducted. Results show that brand authenticity comprises four dimensions: longevity, credibility, integrity, and symbolism. The following studies focus on scale development. A second-order four-dimensional scale with 17 items provides satisfactory psychometric properties. This scale is validated across different brands, product categories, and groups of consumers. Subsequent studies show the discriminant validity of the scale with regard to existing brand-related constructs and its predictive validity. Nomological validity is tested. Results show the importance of indexical, iconic, and existential cues in creating brand authenticity perceptions—in line with the objectivist, constructivist, and existentialist perspectives on authenticity identified in the literature review—, the moderating effect of consumer skepticism, as well as the positive influence of brand authenticity on emotional brand attachment. The role of authenticity in understanding consumers’ reactions to a scandal is also explored. Results suggest that brand authenticity protects brands from negative consequences of a scandal.
The second objective of this research is to understand the situations that might enhance consumers’ interest in authentic brands (chapter 3). Three studies test the influence of uncertainty, exclusion, and self-inauthenticity on consumers’ responses towards authentic brands. Results show that an authentic brand is particularly valued when consumers feel excluded and inauthentic. The effects are observed for specific consumer segments, such as consumers with high brand engagement in self-concept and with high importance of personal authenticity, respectively.
The research concludes with a general discussion of the findings, theoretical and managerial implications, as well as limitations and future research ideas (chapter 4).


identifier: Mak, Chun C.  (2014) Electron Solvation Dynamics in Photoexcited Iodide-Polar Solvent Clusters: A Theoretical Investigation.  PhD thesis, Concordia University.

abstract:
Photoexcitation of halides dissolved in polar liquids results in charge-transfer-to-solvent (CTTS) states in which a halide valence electron has been transferred to a delocalised, solvent-supported orbital.  Subsequent relaxation of CTTS excited solvated halides results in the formation of solvated electrons, ubiquitous species implicated in numerous chemical and biochemical transformations.  Analogues of the CTTS excited states of solvated halides have also been observed in small iodide-polar solvent clusters, and the relaxation of CTTS excited iodide-polar solvent clusters, [I–(Solv)n]*, has attracted significant interest as a paradigm for investigating the
role of individual solvent molecules in trapping and solvating an excess electron.

In this work, a combination of high-level quantum chemical calculations and first-principles molecular dynamics simulations is employed to elucidate the relaxation mechanism of [I–(Solv)n]* (Solv = H2O, CH3CN and CH3OH) and to develop an in-depth understanding of the nature of the molecular motions and interactions involved in the associated electron solvation processes.  A ‘two-level’ approach is employed, in which [I–(Solv)n]* trajectories are propagated on a potential energy surface computed with a relatively modest treatment of electron correlation
and a medium-sized basis set while electronic properties of cluster configurations sampled from the trajectories are computed with a much more rigorous quantum-chemical method and significantly larger basis sets.  Results indicate that [I–(Solv)n]* relaxation involves rapid initial motion of the solvent molecules, leading to the separation of the excited electron from the iodine atom and a concomitant decrease in stability of the excited electron, followed by more gradual reorganisation of the cluster, which can have variable effects on the stability of the excited electron, depending on the type of solvent molecule in the cluster.  In clusters with a strong network of solvent-solvent interactions, such as [I–(H2O)n]*, stabilisation of the excited electron occurs, while in clusters with a weaker network of solvent-solvent interactions, such as
[I–(CH3OH)n]*, solvent cluster fragmentation ultimately results in destabilisation of the excited electron.  Subtle differences in the structural properties of the molecules within the cluster can thus heavily influence the electron solvation process in [I–(Solv)n]*, a reflection of the important role of individual molecules in supporting a solvated electron.


identifier: Chen, Min  (2015) QoS-aware Service Composition and Redundant Service Removal.  PhD thesis, Concordia University.

abstract:
Automatic Service Composition (ASC) is the generation of a business process to fulfill business goals that cannot be fulfilled by individual services. Planning algorithms are frequently used to solve this problem. In addition to satisfying functional goals, recent research is geared towards selecting the best services to optimize the QoS of the business process results. It is a challenge to fulfill functional goals and achieve QoS optimization at the same time.

In this thesis, we propose to combine a planning algorithm called GraphPlan, with a systematic search algorithm like Dijkstra's algorithm to achieve functional goals and QoS optimization at the same time. The GraphPlan algorithm has the advantages of easily modeling business logic, reusing the actions in one plan, and planning parallel actions in a plan. The planning graph generated by the GraphPlan algorithm is a compact representation of all execution paths, which makes it feasible to apply Dijkstra's principle. Two methods have been proposed to combine the Graphplan with Dijkstra's algorithm.

In the first method, we extend Dijkstra's algorithm from working on a single source graph to working on the extended planning graph whose nodes have multiple sources. The advantage of this method is that it gets an optimal plan with the best QoS value for the single criteria of throughput or response time in polynomial time. However, this method does not provide a uniform graph structure (\ie an extended planning graph with single or multiple tag, to generate an optimal plan for all kinds of quality criteria).

In the second method, we improve the idea of combining the Graphplan with Dijkstra's algorithm by providing a uniform graph structure to generate a QoS optimal solution for all kinds of quality criteria. A Layered Weighted Graph (LWG) is generated and provides a uniform structure for the easy use of Dijkstra's algorithm to find an optimal plan for all kinds of quality criteria. By using multi-objective shortest path algorithms, this method can be easily extended to solve QoS optimization on multiple QoS criterion for service composition problem.

In this thesis, we also study redundant service removal to further optimize QoS optimal solutions. The removal of redundant services does not worsen the QoS value of the optimal solution. Fewer numbers of services indicates less execution costs to invoke these services. A redundant service removal problem is modeled as an optimization problem such that the optimal solution without redundancy is found.


identifier: Lamoureux Scholes, Laurie  (2014) Making the Mosaic Work? A Study of the Canadian Interfaith Movement.  PhD thesis, Concordia University.

abstract: In Canada, where one’s religious identity is a private affair, organized interfaith initiatives provide one of the few public forums where one is encouraged to affirm a religious conviction. More and more, Canadians are encountering different religions and spiritual paths in workplaces, neighbourhoods, leisure activities, politics and the daily news.  Alongside these encounters interfaith initiatives have developed, especially in the larger urban centers of Vancouver, Montreal and Toronto. While similar interfaith initiatives can be found across the country, variations in religious populations and pressing political / social concerns have influenced the distinct character of interfaith activities in each centre.  Drawing on findings from 110 in-depth interviews with active members of Canadian interfaith initiatives, this thesis explores the matrix of influences which have contributed to the development of the interfaith movement within Canada and as part of the larger global interfaith movement.  The research examines the motivations, approaches and types of interfaith work practised highlighting the diverse resources the interfaith movement offers for bridging the religious diversity found within the contemporary world.  The study also calls attention to various challenges facing the Canadian and global interfaith movement including questions about representation, missing voices, stagnation, the need for deeper exploration of difference, strategies for intrafaith dialogue, measuring impact, and finding the required resources to build more tools and forums for interfaith work.


identifier: Wu, Sherry  (2015) Comprehensive Bioinformatic Analysis of Glycoside Hydrolase Family 10 Proteins.  Masters thesis, Concordia University.

format: text other

abstract:
Glycoside Hydrolase Family 10 (GH10) contains endo-1, 4-β-xylanase which catalyzes the hydrolysis of xylan, the most abundant hemicellulose in lignocellulosic biomass. In this study, different bioinformatic approaches were used to comprehensively analyze the distribution, the phylogeny, the function and the evolutionary origin of a large GH10 protein dataset. The goal was to explore the correlation between sequence similarity and function of GH10 proteins to better understand xylan utilization pattern within the family.
	Predicted glycoside hydrolase family 10 sequences from fungal, bacterial, archaeal, and non-fungal eukaryotic genomes as well as biochemically characterized proteins were used to perform a phylogenetic analysis. Based on the tree topology, 626 GH10 sequences were classified into 50 well-supported subfamilies. Among the analyzed sequences, 42 remained unclustered. The complex topology of the family tree suggests multiple duplication events followed by lineage specific gene loss during evolution. In addition, the Maximum Likelihood phylogeny of GH10 proteins does not mirror the previously established species taxonomic tree, suggesting that the divergence of the GH10 family ancestral gene preceded the appearance of the eukaryotic lineages.
A set of non-fungal GH10 proteins were manually curated employing criteria used in mycoCLAP, a database for biochemically characterized fungal lignocellulose active enzymes. Experimental data of biochemically characterized GH10 proteins were mapped onto the phylogenetic tree to establish relationships, if any, between biochemical properties and sequence similarity. Only 24 subfamilies contain members with characterization, demonstrating that 26 phylogenetically diverse subfamilies remain uncharacterized. Among the subfamilies with experimental data, a distantly related subfamily with tomatinase activity was identified. By comparing the tertiary structures of well-characterized subfamilies, I have identified subfamilies that display different xylan substrate preferences and hydrolysis patterns. Correlations were also observed between sequence similarity and the pH and/or temperature optimum in the GH10 family. The accumulation of mutations within subfamilies reflects how they have diverged over time.  Subfamily discriminating residue analyses were performed to identify subfamily-specific polymorphisms. Detailed lists of subfamily discriminating residues are provided. The majority of these residues are involved in secondary structure formation based on alignment to 3D structures, suggesting they might be functionally and structurally important.


identifier: Chatri, Imane  (2015) Classification of text documents and extraction of semantically related words using hierarchical Latent Dirichlet Allocation.  Masters thesis, Concordia University.

abstract:
The amount of available data in our world has been exploding lately. Effectively managing large and growing collections of information is of utmost importance because of criticality and importance of these data to different entities and companies (government, security, education, tourism, health, insurance, finance, etc.). In the field of security, many cyber criminals and victims alike share their experiences via forums, social media and other cyber platforms. These data can in fact provide significant information to people operating in the security field. That is why more and more computer scientists turned to study data classification and topic models. However, processing and analyzing all these data is a difficult task.
In this thesis, we have developed an efficient machine learning approach based on hierarchical extension of the Latent Dirichlet Allocation model to classify textual documents and to extract semantically related words. A variational approach is developed to infer and learn the different parameters of the hierarchical model to represent and classify our data. The data we are dealing with in the scope of this thesis is textual data for which many frameworks have been developed and will be looked at in this thesis. Our model is able to classify textual documents into distinct categories and to extract semantically related words in a collection of textual documents. We also show that our proposed model improves the efficiency of the previously proposed models. This work is part of a large cyber-crime forensics system whose goal is to analyze and discover all kind of information and data as well as the correlation between them in order to help security agencies in their investigations and help with the gathering of critical data.


identifier: Rak, Shauna  (2015) Still Dancing: My Bubby’s Story How Family Histories Can Inform Multi-Sensory Learning in Art Education.  Masters thesis, Concordia University.

abstract:
In this Master’s thesis I represent my grandmother’s story of survival during the Holocaust as a narrative of loss, love, and dancing. This qualitative and creative research project is informed by in-depth interviews with my grandmother, life writing, sustained reflection on my own life experiences, and a recent research trip to Poland where I visited key sites linked to my grandmother’s story. During the research process, I also considered the ways my Bubby’s story has shaped my identity as a third-generation survivor, as I have been deeply influenced by her perspective on life. Through my use of oral history, life writing and an art installation, I have gained greater understanding of the significance of multi-sensory learning, storytelling and creative art initiatives and recognize these methods as meaningful tools for Holocaust education.
For me, the thesis has initiated ongoing research into the effects of memory, multi-sensory learning and creative art practices. For a larger audience, I suggest that this use of story can enhance multi-disciplinary learning, illustrate the complexities of the Holocaust through artful renderings, and inspire educators to adopt creative and powerful pedagogic tools in teaching the history of genocide.


identifier: Moein Namin, Elnaz  (2015) Demand Forecasting and Location Optimization of Recharging Stations for Electric Vehicles in Carsharing Industries.  Masters thesis, Concordia University.

abstract:
Carsharing is an alternative to private car usage. Using electric-vehicles as a substitute to fuel vehicles is a wiser option which leads to lower fuel emissions, more energy savings and decreased oil dependency. However, there are some barriers in using electric vehicles at large scale in carsharing companies. Battery power limitation and lack of sufficient infrastructures are some of them. Accurate demand forecasting is a must for this purpose.
In the first part of this thesis, we investigate the demand forecasting problem for carsharing industries and apply four techniques namely simple linear regression, seasonally adjusted forecast, Winter's Model and artificial neural networks to decide the right number of vehicles to be made available at each station to meet the customer requests. The results on randomly generated test datasets show that artificial neural networks perform better over the other three.
In the second part, we investigate the location planning problem of recharging stations for electric vehicles. The base model used for this study is the mathematical optimization model proposed by Wang & Lin (2013). Firstly, we improve their MIP model and solve it using AIMMS (Advanced Interactive Multidimensional Modeling System). Secondly, we propose Genetic Algorithm for the same problem and implement it in Matlab. The obtained results are compared with previous work done by Wang and Lin (2013). The comparisons show better performance of the proposed methods.


identifier: Warwick, Elizabeth  (2015) An Observation Tool for Self-Regulatory Events in Music Teaching (T-SREM): Development and Testing of a Video Coding Tool for Music Lessons.  Masters thesis, Concordia University.

abstract:
Many young people embark on music lessons during childhood, but few pursue such instruction beyond a few years’ time, thus missing out on the life-long pleasure of making music for oneself. Problems with children’s self-regulation of learning, particularly the three-phase cycle of forethought, performance, and reflection proposed by Zimmerman (2000, 2006, 2008, 2011), may influence the abandonment of formal music lessons, as suggested by the research of McPherson and his colleagues (McPherson et al., 2012; McPherson & Renwick, 2011; McPherson, Nielsen, & Renwick, 2013; McPherson & Zimmerman, 2011). As part of a larger project examining self-regulation and music learning in the digital age, an observation tool for coding self-regulatory events in music lessons was developed.
The tool uses categories from Zimmerman’s self-regulatory cycle of learning to code verbal and nonverbal interactions and behaviours of teachers and students in videotaped music lessons. The iterative process of the tool’s development is presented and discussed, including an analysis of issues around using videotaped material. Results from a pilot test, in which researchers coded 12.9 hours of videotaped lessons from four music teachers in the Greater Toronto Area, are given. Patterns in self-regulated learning that emerged during the pilot test are explored, suggestions for triangulating the results with other project data are presented, and suggestions for further research are given.


identifier: Zhang, Yingxiao  (2015) Geography and Firm Performance: Evidence from Chinese Listed Private Enterprises.  Masters thesis, Concordia University.

abstract: We investigate the effects of geography on firm performance and agency costs. We argue that non-urban firms, which located in sparsely populated areas, have location disadvantages. Shareholders can’t efficiently oversee the management of non-urban firms because of the long distance. Using a sample of 1036 Chinese private firm observations for the year 2013, we do univariate tests and multivariate regressions to study the relationships between location dummy (equals to 1 if firms are urban-located and 0 otherwise) and firm performance. We find that urban firms have better corporate governance structure, lower agency costs and better firm performance measured by Tobin’s Q. We then substitute location dummy with population size of the city to do robustness tests. The results show that firms located in populated areas perform better and have lower agency costs. According to agency literature, firms pay higher dividends to mitigate the increased agency costs. So we study the dividend policy of urban firms and non-urban firms to study whether non-urban firms have adjusted their corporate policies to solve their severe agency conflicts. Consistent to agency literature, we find that non-urban firms, which have more information problems and agency costs, pay higher dividends.


identifier: Gao, Yunfeng  (2015) Turbo and Raptor Coded SIC Receiver Performance for the Coexistence of LTE and Wi-Fi.  Masters thesis, Concordia University.

abstract:
In this thesis, a coexistence of LTE and Wi-Fi is proposed. We assume that
both LTE and Wi-Fi transmit in the same band simultaneously, the Wi-Fi signal,
which is assumed to be the stronger signal, can be decoded first. We can achieve a
good performance of LTE transmission by using a Successive Interference Cancellation
(SIC) scheme. The LTE signal, which is the weaker signal, can be decoded
successfully as though there is no Wi-Fi interference. We implement a Raptor
code for Wi-Fi and a Turbo code for LTE. By adjusting the code rate, the Raptor
codes are adaptive to diferent channel conditions especially with interference.
Meanwhile, the Turbo codes are standardized in LTE transmission.
We propose a new antenna integration design, in which only one antenna is
used. As a result, the space of mobile devices can be saved and the interference
caused by diferent transmissions can be avoided.
Then, we study two scenarios based on diferent channels. Under the first scenario,
a primary user and a secondary user transmit their own signals over the
same AWGN channel. The simulation results indicate that by using a SIC scheme,
an increasing system capacity can be obtained by the secondary transmission, with
no sacrifce of the primary user's performance.
In the second scenario, the LTE and Wi-Fi transmit over a Rayleigh fading
channel simultaneously. A straightforward estimation scheme is adopted to estimate
the Channel State Information (CSI) at the receiver. We discuss two cases
according to the CSI. The first case is that the CSI is available at the receiver.
A novel scheme is proposed to overcome the disadvantages of a slow block fading
channel. In this scheme, we implement an interlever at both the transmitter and
receiver, and therefore utilize the CSI efficiently at the receiver to improve the
system performance. In the second case the CSI is available at both the transmitter
and receiver. An adaptive power control scheme is proposed to adjust the
transmitted power to a desired level, and therefore improve the system.


identifier: Singh, Mukhbir  (2015) The Effect of Debt Covenant Violations on Debt Issuance Behaviour.  Masters thesis, Concordia University.

abstract: We examine how contract term restrictions influence debt issuance behaviour and find that debt covenant violations impact firms’ debt maturity structure, costs, syndicate structure, collateralization and placement choice. Using the issuance of debt by non-financial firms between 1996 and 2008, we find that debt maturity decreases following a firm’s debt covenant violation while debt costs and covenant intensity increase. Debt seniority does not appear to have a strong relationship with covenant violations – firm size and firm quality have the biggest impact on seniority of debt issuance. We also show that the use of syndication and secured debt increases following a covenant violation. Our analysis demonstrates that the majority of the impact of the change in our dependent variables is observed following the first violation. Our analysis also includes the choice between public and private debt. We show that, following a covenant violation, firms are more likely to place their debt privately. Our findings help understand how the changes in the information and governance environment that follow a covenant violation affect future debt issuance behaviour.


identifier: Taghavi, Seyedmorteza  (2015) Design of Synchronous Reluctance Machines for Automotive Applications.  PhD thesis, Concordia University.

abstract:
This dissertation reports an appropriate design methodology for synchronous reluctance machines, their important technical issues, and possible solutions for traction applications. The synchronous reluctance machines are used in industries owing to their unique merits such as high efficiency, fast dynamic response, and lower cost. Considering these superior properties, recently, this smart synchronous topology became more attractive for electrified powertrain applications in automotive industries. However, compared to the major requirements of the traction motors such as high torque and power density, low torque ripple, wide speed range, and proper size, this machine is still under investigations.
The goals of this research work are first; to identify electrical, magnetic, and geometrical parameters which are dominant in the machine’s performance, and second; to verify appropriate design methodology for achieving a higher performance for automotive applications. Hence, analytical and computer aided analysis followed by experimental examinations on prototypes are carried out to support proposed methods and address possible solutions to the machine’s technical issues for these particular applications.
Accordingly, the synchronous reluctance machine’s fundamental operations, electrical, magnetic, and geometrical parameters are investigated. Analytical approach and a sizing methodology corresponding to the desired specifications are presented through the machine’s mathematical model. Design of transversal laminated anisotropic rotor structure with different geometries is studied to identify the geometrical parameters effects on the machine’s performance in particular the output torque and torque ripple. An appropriate geometrical method along with an innovative rotor lamination assembly are proposed for improving the machine’s output functions such as torque, power, and saliency ratio. Finally, the future perspective of the research work is discussed for further investigations.


identifier: Gafoor, Keisha  (2015) Siblings of Children with Autism: Sibling Support Intervention Program.  Masters thesis, Concordia University.

abstract: The Sibling Support Intervention Program (SSIP) was created specifically for siblings of children with autism to provide these children with the opportunity to voice their perspective and needs, and to empower them within their family dynamics by developing stronger and more understanding relationships within their family (e.g., D’Arcy et al., 2005; Dyson, 1998; Evans et al., 2001).  Six children (3 in control group and 3 in experimental group) between 7- and 13-years-old participated in six weekly, two and a half hour sessions. The perceptions and experiences of the children and their parents of the SSIP were obtained through the use of semi-structured interviews, the Piers-Harris Children’s Self-Concept Scale (Piers & Herzberg, 2002), the Behavioural Assessment System for Children (Reynolds & Kamphaus, 1988; 2004), as well as video-taped group observations. Descriptive findings suggest that children often benefitted from information about autism, and the strategies were deemed somewhat beneficial to sibling interactions and helped typically developing children to recognize their sibling’s abilities and limitations. In addition, children’s self-concept and their parents’ reports of internalizing and externalizing behaviors of the experimental group showed improvements from the pre-group session interview and the post-group session interviews. However, there were no consistent changes noted for the control group. The parents’ perceptions of family dynamics indicated little change between pre- and post-group.


identifier: Tarnowetzki, Lindsay  (2015) Environmental Storytelling and BioShock Infinite: Moving from Game Design to Game Studies.  Masters thesis, Concordia University.

abstract: Environmental storytelling is an interesting concept for games studies scholars because it unites both narratology and ludology, offering a solution to one of the most contentious arguments in the history of the discipline; one that pitted narrative against gameplay. Despite this, the term itself is not often used in games studies scholarship, even if related themes are being explored, which indicates that this concept and term are more entrenched in game design theory than games studies. I have used Smith and Worch’s characteristics of game environments and environmental storytelling to examine how these concepts function within BioShock Infinite. I have also expanded upon these definitions in order to propose that there are three different game environments within BioShock Infinite: the avatar’s physical environment, the avatar’s social environment, and the extradiegetic environment. This theoretical work as well as using game studies sources to support my work facilitates a shift in the discussion of environmental storytelling from game design and literature into game studies.


identifier: Szanto, David Andrew  (2015) Performing Gastronomy: An Ecosophic Engagement with the Liveliness of Food.  PhD thesis, Concordia University.

abstract: This dissertation is a contemporary reinterpretation of gastronomy, weaving together performance, systems theory, and material practice with the historic sense of the term, ‘the communication of food knowledge’. It proposes a transdisciplinary approach to food scholarship that figures food as lively, complex, and intersubjective, and which responds to the performative, self-transforming nature of food systems. The move towards performativity is motivated by Felix Guattari’s concept of ecosophy, a call for ecological-philosophical consciousness about the choices and actions we make in the world. Acts of thinking and doing with food have ethical and political implications; a performative approach addresses these complex articulations, while attending to questions of power, privilege, and authority. Experimental and exploratory research is described, which focuses on a number of food milieus, an expression that denotes hybrid spaces in which humans and food interact. As a whole, the work is aimed at answering the question What if? concerning the ways that we come to understand food milieus more broadly, in order to respond to the issues and potentials that food systems present. Through case-based interventions within three food milieus, a context and rationale for performative gastronomy is constructed. The first case treats the urban foodscape of boulevard St-Laurent (Montreal, Québec), a commercial area in the centre of the city that is characterized by both change and stability. The second involves the sensory art installation, Displace (Montreal; The Hague), in which taste and cooking are examined as occasions through which matter performs. A third case addresses the University of Gastronomic Sciences (Pollenzo, Italy), and involves an examination of pedagogy and reflection as a mode of research. The written dissertation acts in concert with an October 2014 ‘performative meal event’, which revisits key questions about the milieu of gastronomy. Together this work critically engages with discourse and practice in food studies, ecology, performance, autoethnography, and design, building towards long-term implications for ecosophic, food-related scholarship and praxis.


identifier: Rodriguez Milanes, C.M.  (2015) CEO Turnover after Poor Performance: Turnaround or Scapegoating?  Masters thesis, Concordia University.

abstract:
This paper explores whether firms that dismiss their Chief Executive Officers (CEOs), due to poor corporate performance, exhibit better performance after the CEO turnover, or whether the CEO dismissal merely serves a scapegoating function. We examine whether companies that were in the eye of the public due to disappointing results recover after dismissing their CEO. We match firms in the same industry, by size, and Altman Z-Score and compare our turnover sample with this matched group of firms that did not dismiss the CEO. Our results suggest that CEO turnovers do not translate into better operating performance, or firm valuation (Tobin’s Q). However, we do find that, after some delay, the market reacts positively to CEO dismissals due to bad performance: Underperforming firms that fire their CEOs exhibit positive and significant abnormal returns, while their counterparts, who retain their CEOs, exhibit negative abnormal returns.

Key words: CEO Turnover, Scapegoating, Performance


identifier: Morgenstern, Tyler  (2015) Endurant Bodies/Atmospheric Borders: Race, Indigeneity, and Transmedia Art in Contemporary Canada.  Masters thesis, Concordia University.

abstract: Interrogating post-9/11 shifts in the institutional and discursive organization of policing and incarceration capacities, state surveillance practices, and citizenship and immigration policy, this work argues that the contemporary Canadian state manages the boundary between the (normatively white) social body it names and its Indigenous and racialized Others by way of an atmospheric bordering regime. An ambient system of disciplinary pressures that overreaches the state’s territorial limits, this regime functions as a technology, simultaneously representational and irreducibly material, for moving bodies through and removing bodies from the state by consolidating and ascribing, to some bodies more than others, particular forms of racial and Indigenous difference – interrelated and co-constitutive, yet never strictly equivalent. Through this process, racialized and Indigenous bodies are variously configured as strange, backward, and contaminating; as ‘points of tension’ that, for threatening to rend a “shared atmosphere” (Ahmed, 2014, para. 15) of national belonging, are targeted for exclusion, expulsion, and elimination. While tracing how these dynamics weave through specific discursive artefacts (policy documents, press releases, news reports, legal proceedings, and governmental pronouncements), I also emphasize how critical representational practices might hold open the possibility of contestation. To this end, I turn to the work of four contemporary Indigenous and racialized artists working in Canada, exploring how their transmedial practices recast our embodied encounters with difference, and help us to grasp at ways of being in touch with o/Others across and against the racial and (settler) colonial logics embedded in the labour of atmospheric bordering.


identifier: Kielback, D.J.  (2015) Indicators of Sustainable Development in Higher Education Institutions: A Case Study of Concordia University.  Masters thesis, Concordia University.

abstract:
The concept of “sustainability” is at the forefront of many research concerns and is at an increasing rate being incorporated into the activities of post-secondary institutions. Sustainability has become such an important issue that it has become part of the “marketing” of an institution. Sustainability self-assessment tools have been developed to guide sustainable developments and allow institutions to display their performances across a range of sustainability measures. Given the growing use of these indices among institutions of higher education, this thesis investigates to what extent “sustainability” practices are adopted in a university-wide setting, and how conscious university administrators are that such practices may translate into higher enrolments; or, serve to attract those prospective students seeking a more “green” learning environment.
Using Concordia University as an example, this case study asks a sample of university administrators how sustainability in higher education impacts the university’s reputation, prestige, and rank, and then examines how Concordia University plans to pursue sustainable development. The research reported here shows that about 54% of Concordia’s research centres and 61% of Senate-recognized centres have a sustainable research focus. Interestingly, all of Concordia’s “sustainability-centric” research centres have been developed since 2009.  From 2012 to 2014, 80% of the main advertisement campaign focused on sustainable research developments. In terms of the future, results of this research show that the university is mapping its student activities and sustainable assets for more effective developments, while continuing to improve its position in its sustainability self-assessment, and its attempt to create a sustainable minded culture. It is clear from this research, the thesis concludes, that Concordia University definitely believes investing in its sustainability will empower its mission and vision, and is pursuing it through unique ways.


identifier: Jones, Brice C.  (2015) New Testament Texts on Greek Amulets from Late Antiquity and Their Relevance for Textual Criticism.  PhD thesis, Concordia University.

abstract:
This dissertation examines New Testament citations on all Greek papyrus and parchment amulets from late antique Egypt. Since New Testament textual criticism does not allow for the inclusion of non-continuous manuscripts (of which amulets are a part) in the official catalogue of manuscripts, a large body of textual evidence has fallen outside the purview of scholars. This dissertation, which constitutes the first systematic treatment of non-continuous manuscripts, seeks to remedy the situation in part by determining the ways in which New Testament texts on amulets may be useful for textual criticism.

This dissertation has three main objectives. The first objective is to define more closely the categories of continuous and non-continuous by formulating criteria for the identification of the latter. The second objective is to propose a method for analyzing the texts of non-continuous artifacts in terms of their text-critical value. The third objective is to establish a comprehensive database of one category of non-continuous artifacts (amulets) and provide a detailed analysis of both their texts and containers (i.e., physical manuscripts).

By analyzing a largely untapped source of New Testament textual data, this project contributes to a methodological question in textual criticism concerning its categories and provides a wealth of source material for the study of the reception of the Bible in early Christianity. Thus, while the study is targeted at textual critics, it contributes to a conversation about early Christianity that is much larger than the project, as these texts demonstrate the various ways in which early Christians used scripture.


identifier: Rezabeigi, Ehsan  (2015) Development of highly porous polylactic acid-based monoliths containing sol-gel-derived 45S5 Bioglass®.  PhD thesis, Concordia University.

abstract:
It has been shown that highly porous composite scaffolds consisting of biodegradable polymeric matrices and well-dispersed bioactive glass nanoparticles have a great potential for creating the ideal scaffold for tissue engineering purposes. In spite of this, the scaffold with ideal morphology, degradation rate and mechanical properties has not yet been developed.
In the first stage of this study, the most bioactive glass composition, 45S5 Bioglass® (45% SiO2, 24.5% CaO, 24.5% Na2O and 6% P2O5 (wt.%)), was synthesized by a straightforward, nitrate-free sol-gel method. This route allowed for the production of a fully amorphous product with an appropriately high specific surface area (11.75 m2/g), which is expected to have an excellent bioactivity for bone regeneration applications.
In the second stage, a fundamental study was performed on the PLA – dichloromethane (solvent) – hexane (nonsolvent) ternary system which was essential for the subsequent production of porous PLA monoliths from this system. The ternary phase diagram of this system was experimentally developed at room conditions in order to identify the liquid-liquid phase separated region. The phase separation kinetics were also studied using turbidity measurements, showing that a small increase in PLA content can significantly increase the phase separation rate of the system.
The third stage of this study involved the fabrication of PLA foams using a solvent-based foaming process: nonsolvent induced phase separation (NIPS), which is a template-free and a very versatile technique. For this purpose, systems from the liquid-liquid phase separated region were selected and allowed to phase separate at various temperatures and then gel. Shrinkage of the gels during drying was monitored in order to identify compositions with minimum shrinkage and highest porosity. This method was able to produce semi-crystalline PLA foams with high specific surface area (up to 54.14 m2/g), high porosity (up to 90.8%) and compressive modulus ranging from 1.8 to 57 MPa. Crystallization during phase separation and the phase separation mechanisms were explained and discussed for various compositions and conditions. Depending on the ternary composition and the phase separation standing temperature, mesoporous and combined meso/macroporous morphologies were produced. The latter morphology is very promising for bone scaffold applications since the macropores are vital for vascularization and bone ingrowth whereas the mesopores are expected to enhance cell attachment onto the structure.
In the last stage of this study, the sol-gel-derived 45S5 Bioglass® was surface modified with a silane coupling agent (methacryloxypropyltriethoxysilane) in order to improve its interfacial compatibility with PLA. This process effectively increased the stability of the glass particles in PLA solutions. It also diminished the agglomeration of glass particles. Surface modified glass particles (2 wt.%) were subsequently incorporated into the NIPS foaming process to produce composite foams. It was shown that the particle incorporation route (via solvent or nonsolvent) had the greatest impact on morphology, porosity and crystallinity of the resulting foams. An incorporation of 2 wt.% of particles via nonsolvent significantly decreased the porosity and crystallinity of the PLA matrix. The incorporation of particles via solvent increased the average size of the macropores and made them more homogeneous in terms of size. It also slightly increased the porosity of the foams whereas no impact on the crystallinity of their PLA matrices was observed. SEM examination revealed that the surface modified particles were incorporated within the open mesoporous structure of the foams where they can simultaneously be in contact with the physiological fluids.


identifier: Almeida, Hayda  (2015) A Supervised Learning Approach for Imbalanced Text Classification of Biomedical Literature Triage.  Masters thesis, Concordia University.

abstract:
This thesis presents the development of a machine learning system, called mycoSORT , for supporting the first step of the biological literature manual curation process, called triage. The manual triage of documents is very demanding, as researchers usually face the time-consuming and error-
prone task of screening a large amount of data to identify relevant information. After querying scientific databases for keywords related to a specific subject, researchers generally find a long list of retrieved results, that has to be carefully analysed to identify only a few documents that show a potential of being relevant to the topic. Such an analysis represents a severe bottleneck in the
knowledge discovery and decision-making processes in scientific research. Hence, biocurators could
greatly benefit from an automatic support when performing the triage task. In order to support the triage of scientific documents, we have used a corpus of document instances manually labeled by biocurators as “selected” or “rejected”, with regards to their potential to indicate relevant information about fungal enzymes. This document collection is characterized by being large, since many results are retrieved and analysed to finally identify potential candidate documents; and also highly imbalanced, concerning the distribution of instances per relevance: the great majority of documents are labeled as rejected, while only a very small portion are labeled as selected. Using this dataset, we studied the design of a classification model to identify the most discriminative features
to automate the triage of scientific literature and to tackle the imbalance between the two classes of documents. To identify the most suitable model, we performed a study of 324 classification models, which demonstrated the results of using 9 different data undersampling factors, 4 sets of features, and the evaluation of 2 feature selection methods as well as 3 machine learning algorithms. Our
results demonstrated that the use of an undersampling technique is effective to handle imbalanced datasets and also help manage large document collections. We also found that the combination of undersampling and feature selection using Odds Ratio can improve the performance of our classification model. Finally, our results demonstrated that the best fitting model to support the triage of scientific documents is composed by domain relevant features, filtered by Odds Ratio scores, the use of dataset undersampling and the Logistic Model Trees algorithm.