identifier: Davoodi, Sahar  (2007) Building composites based on by-products.  Masters thesis, Concordia University.

abstract: This research program studies replacing part of PVC by a by-product material (lignin) in the plasticized PVC-wood flour composite formulation. Moreover, it studies and experiments different coupling agents to improve the interface between polymer matrix and wood flour.  For these purposes, series of PVC-wood flour control and blend formulations with different amount and type of lignins and wood flour were prepared. This process also included selecting the effective additives and adequate processing parameters for new formulation of PVC-lignin-wood flour composite to enrich the best properties. Tensile and thermal properties, as well as torque values are evaluated to choose the best formulation.  As a result, an effective heat stabilizer, lubricant and proper processing parameters were established. Although replacing part of PVC with large amount of lignin did not result in a composite with desired properties, significant improvements in tensile properties were attained when the concentration of alcell lignin in composite was of 1 and 2phr. Alcell due to its polar groups acts as an effective coupling agent and increases the interfacial adhesion between plasticized PVC and wood flour, so it improves the performance of the composite.


identifier: Mozumder, Md. Sharif Ullah  (2007) Estimation of the Lévy measure for the aggregate claims process in risk theory.  Masters thesis, Concordia University.

type: Thesis NonPeerReviewed

abstract: Lévy processes (LP) are gaining popularity in actuarial and financial modeling. The Lévy measure is a key factor in the versatility of LP applications. The estimation of the Lévy measure from data is shown to be useful in analyzing the aggregate claims processes in Risk Theory.  Starting with infinitely divisible distributions (IDD), some nice constructions are obtained for finite sums of Lévy processes. The Lévy properties of compound Poisson processes are extensively used in the thesis. Examples illustrate the close relationship between IDDs and Lévy processes.  The Poisson random measure associated with jumps of a Lévy process exceeding a given threshold is discussed and a new derivation is obtained. The relation with subordinators (increasing Lévy processes) is explored. Intuitive ideas and results are obtained for the jump function G appearing in Lévy's characterization of the Lévy-Khinchine formula. A non-parametric estimator of G is discussed. A detailed relation between G and p, the Lévy measure, is derived, yielding an estimator of p. The latter gives an estimator of the Poisson rate n f and the claim size distribution F f for claims larger than the threshold f. Extensive numerical simulations illustrate the paths of gamma, inverse Gaussian and {460}-stable claim subordinators and their corresponding estimates for n f and F f


identifier: Mousavinasab, Seyed Yousef  (2007) Detecting influenza epidemics using hidden Markov models with Bayesian approach.  Masters thesis, Concordia University.

abstract: In this thesis, we present a statistical method for detecting influenza epidemics. First, we use a hidden Markov model with Bayesian approach to partition the influenza data into two groups, one group for the epidemic states and another one for the non-epidemic states. Then, we detect the start of the epidemic phase of the disease through introducing a warning threshold. This warning threshold is efficient in increasing the detection rates while decreasing the false alarm rates. Finally, we compare the established hidden Markov model with the traditional seasonal ARIMA model.


identifier: Hortop, Eric  (2007) A symmetry-group semantics for shape grammars : lattice methods for the classification of strand-based patterns.  Masters thesis, Concordia University.

abstract: In ascribing information to designs, two of the purposes a researcher could have in mind are to classy designs, grouping them with similar designs and highlighting specific characteristics, and to store information for reproducing them. The notations and methods for these two tasks are likely to be different.  In the Generative Design Project, researchers have undertaken classification of two-dimensional repeating patterns using symmetry groups, and storage for reproduction using a restricted form of shape grammars. This thesis demonstrates an approach to ascribing symmetry groups to shape grammars, allowing a researcher to concentrate their efforts on representing an artefact or collection, while retaining the benefits of a standard classification.  This work defines a class of strand-based repeating patterns to which this approach is suited, outlines shape grammars in general and in a restricted context-free form, It also defines the symmetry information which is the output of the process starting with broad categories of isometric groups and working down to the information required to fully describe the symmetries of interest.  The thesis also provides set, scalar and vector lattices used in the approach, and provides a novel, consistent method for carrying out the assignment of groups to grammars using those lattices and additional tests to bound the symmetries possible in the language of a given grammar conforming to the restrictions discussed. By establishing a symmetry-group semantics for shape grammars, this thesis allows a pattern or family of patterns to be more fully described by its shape grammar without requiring separate rendering and classification work


identifier: Bobos-Kristof, Georgeana  (2007) The development of the modern integration theory from Cauchy to Lebesgue : a historical and epistemological study with didactical implications.  Masters thesis, Concordia University.

abstract: In this thesis, we describe the historical development of the modern integration theory by presenting the key ideas and insights that led to its shaping, from the first rigorous definition of the definite integral given by Cauchy in 1823, to Lebesgue's theory as it first appeared in his doctoral thesis of 1902. In the final part we also present recent approaches in integration theory. We show that various problems motivated the enrichment of the notion of integral, while one in particular constituted the most important trigger of this development from the beginnings well into the 20th century: the search for a better understanding of Fourier series.  For our study, we principally look at original sources, and we provide detailed proofs for important results, often by elaborating on the authors' sketchy or heuristic arguments, malting thus the original results accessible to the modern reader.  We then use this historical and epistemological analysis to raise some issues related to the teaching of integration at various levels at university, i.e., in calculus, analysis and measure theory courses. For this, we look at some typical textbooks and, inspired by the historical analysis, we give some suggestions for teaching. Our findings show that there might be some conceptual gaps between subsequent levels that are not necessarily insuperable, but require careful didactical analysis.


identifier: Shen, Biao  (2007) Reactions of biologically important thiols with nitroxyl (HNO) and development of a HNO marker.  Masters thesis, Concordia University.

abstract: Biologically active nitroxyl (HNO) is one of the least understood nitrogen oxides. It may play a distinct role from NO in protecting the cardiovascular system, and thiols are suspected to be a major nitroxyl target. The major low-molecular-mass intracellular antioxidant, glutathione (GSH), is an important regulator of cellular homeostasis, and is the most likely biological target of HNO. Cysteine (Cys) and HCys (HCys) are naturally occurring thiol-containing amino acids with antioxidant properties and their levels have been linked to many diseases. Reactions of these thiols with Angeli's salt (AS), a HNO donor, were investigated here.  N -acetyl-glutathione and N -acetyl-homocysteine were used in this study but are unavailable commercially. An efficient and simple method was developed to prepare N -acetylated low-mass thiols from the corresponding disulfides (e.g., GSSG, homocystine) in aqueous buffer using sulfosuccinimidyl acetate (NHSA) followed by disulfide reduction by immobilized tris (2-carboxyethyl)phosphine (TCEP). The pK a values of the low-mass thiols used here were determined by pH titration in 0.15 M KCl using the GLpKa instrument.  GSH was incubated with AS for 30 min and room temperature, and the products were analyzed by ESI-MS. The sulfinamide (GSONH 2 ) and disulfide (GSSG) were formed at pH>5 but GSSG was the dominant product at higher pHs and GSH concentrations. Disulfides only were detected in the incubations of AS with Cys, N -AcCys, HCys, and penicillamine at pH>5. N -acetylation of penicillamine decreased its reactivity with HNO and led to sulfoxide disulfide (RSOSR) formation. Control experiments with NaNO 2 revealed that the products formed in the AS incubates are due to reaction with HNO at pH>5 but with HNO 2 at pH<4, which yields S -nitrosothiols. The results provide the first comparative study of HNO reactivity with biologically important low-mass RSHs. Furthermore, the efficient conversion of GSH to stable GSONH 2 and GSSG products is consistent with the reported depletion of intracellular GSH by HNO.  At present, HNO is detected mainly by monitoring its dimerization product, N 2 O. Since N 2 O can arise from other reactions, a specific method of HNO detection is desirable. The high reactivity of thiols with HNO to form sulfinamide was examined as a method of HNO detection. The CysGlu and CysAsp dipeptides, with two negative charges at the C-terminus, exhibited high sulfinamide yields at pH {598}7.4, and are good candidates for the further development of a HNO marker.


identifier: St. Martin, Mark  (2007) Evil and demonological influences in the life and development of Saint Martin of Tours.  Masters thesis, Concordia University.

abstract: St. Martin of Tours had a significant impact on the development of Christianity throughout northern Europe. No other Saint is as heavily represented in France today as St. Martin of Tours. Clearly this man was an exceptional representative of the church. But what events helped to shape him into the man we know him as today? Why is he unique among his contemporaries for that matter?  Perhaps the most intriguing aspect to this man is his unyielding nature in the opposition of evil. If that is in fact the case, what sort of influence did evil have on the development of this man? Perhaps if one could identify what the term evil means in terms of St. Martin, one could then proceed to identify what makes St. Martin unique


identifier: Renée., Brousseau (Touma)  (2007) Beyond the monastery walls : rebirth of lay monasticism.  Masters thesis, Concordia University.

abstract: In the last decades, an increasing numbers of Christians are drawn to a disciplined spiritual lifestyle (asceticism) and are finding new forms to express their spirituality by joining the secular and religious world. This research elaborates on this fact, presenting lay ascetic communities as well as individuals in North America and around the world, who have chosen lay asceticism as a Christian way of life.  Throughout this work, concepts and vocabulary are clarified in order to eliminate misconceptions and facilitate understanding. One constant preoccupation was to keep objectivity; in order to achieve this, a wide variety of sources was consulted from various cultures, eras and realms.  The facts uncovered in this research not only unveil new opportunities for all Christians whether they be male or female, celibate, married, or family groups, but they also challenges Christian individuals to remember that in order to live the Gospel values one needs to discipline oneself.  It challenges Institutions to revise what spiritual nourishment church communities offer, to find spiritual guides and to open new spiritual status for laity. It also challenges theologians to search for a new understanding of chastity, of the theology of the body and the theology of marriage


identifier: Smith, Jen  (2007) "Authentic" experiences in Turkey : performances, constructions, and productions of hosts and guests at George House.  Masters thesis, Concordia University.

abstract: This study examines the different kinds of authentic experiences had by international guests who came to George House, a popular guesthouse in the southwest of Turkey, between August and November in 2006. For the purposes of this thesis, authenticity is not something that is found but rather something that is socially constructed by both hosts and guests. Throughout this work constructive and existential approaches to authenticity are used together and as compliments to one another. International guests staying at George House have many sorts of experiences through which they negotiate and work towards the achievement of authenticity. These complex experiences revolved around three types of relationships and interactions. Firstly, there are those that revolve around and are connected to the hosts such as the ways in which the hosts perform authenticity through sharing their everyday life with their guests and also by serving "traditional" dinners. Secondly, there are experiences and interactions that revolve around inter-personal relationships with other guests, both international and Turkish, through the sharing of a touristic communitas. Lastly, there are intra-personal experiences with one's self that engage and challenge the body thus leading to the achievement of personal authenticity. Following the George House experience from hearing about it, to experiencing it, and lastly, to leaving it the productions, constructions and performances of authenticity by both hosts and guests are exemplified.


identifier: Tan, Weiwei  (2007) An integrated view of cognitive absorption in a technology-mediated learning environment.  Masters thesis, Concordia University.

abstract: Organizations today allocate a significant amount of their budget in information technologies dedicated to improve their learning/training processes capabilities. While there has been a wealth of empirical research on technology-mediated learning/training, most tend to focus on instrumental beliefs as drivers of individual intention toward information technologies. However, in recent years, more and more researchers advocate the influence of individuals' holistic experience with the learning systems and associated intrinsic motivational drivers on intentions and acceptance.  The present study is motivated by the need for a better understanding of cognitive absorption as an intrinsic motivational driver to use technology-mediated learning systems. To that effect, the present study proposes an integrated research model based on the theory or reasoned action, theory of planned behavior and the technology acceptance model, to empirically investigate the impact of cognitive absorption on the belief-intention structure of individuals' behavior.  A web-survey was administered to 105 students after they have used a multimedia learning environment that aimed to help them study for an online course. Results suggest that individual technology acceptance behavior is a function of their holistic experience with the technology and cognitive perceptions formed by rational assessments and these impacts are mediated by individuals' attitude toward the technology. The study offers a motivation perspective to the technology adoption research, and provides empirical support on predictors of individual behavior towards the use of multimedia learning systems in higher education. Findings provide insight to the implementation of multimedia learning and information system design


identifier: Wang, Zheng  (2007) How parent-child relationship affects adolescents' compulsive buying behaviour through the mediator of self-esteem.  Masters thesis, Concordia University.

abstract: Consumer compulsive buying is an important area of inquiry in consumer behaviour research. While the previous studies on the relationship between compulsive buying and familial variables have been implied by research in social sciences and mainly about adults, it has not yet been examined fully in the marketing literature. The present study addresses this void by investigating how three parent-child relationship factors (cohesion, expressiveness and conflict) could have both direct and indirect (through the mediator of self-esteem) effects on children's compulsive buying behaviour.  This research investigated the relationship among three major concepts, i.e. parent-child relationship, self-esteem, and adolescents' compulsive buying behaviour. The parent-child relationship was measured according to fathers', mothers' and children's responses. The findings indicated that both parent-child relationship and self-esteem may affect significantly the extent of adolescents' compulsive buying behaviours. Gender, availability of pocket money and involvement in part-time jobs were also found to predict children's compulsive buying behaviour in a sample of Canadian adolescents. Both theoretical and practical implications are discussed in the study. Suggestions for future research are also offered at the end.


identifier: Robinson, Melanie  (2007) A laboratory study of the moderating effect of task importance on the relationship between transformational and transactional leadership styles and outcomes.  Masters thesis, Concordia University.

abstract: This study investigated task importance as a moderator of the relationship between four transformational and transactional leadership styles (charisma, intellectual stimulation, contingent reward, and no leadership) and six outcomes (performance quantity and quality, satisfaction with the leader, perceived leader effectiveness, task interest/enjoyment, and extra effort). The sample for this study was composed of 102 undergraduate students (45 males, 57 females). Each participant viewed one of four videos, created for this study, in which a leader (as portrayed by an actress) displayed the characteristics of one of the leadership styles noted above. Task importance was manipulated by providing participants with handouts designed to convey either high or low task importance. Participants completed an in-basket exercise adapted from Howell and Frost (1989). The findings showed a significant main effect of the leadership condition for three outcomes--performance quantity, task interest/enjoyment, and extra effort. The interaction effect was marginally significant for two outcomes--performance quality and satisfaction with the leader. Contrary to expectations, contingent reward leadership emerged as the best predictor of the outcomes--while the effect of contingent reward leadership was not significant for all outcomes in this study, a pattern emerged whereby participants in the contingent reward leadership condition reported highest scores for five of the six outcomes investigated in this study. The study's contributions and limitations, along with directions for future research, are discussed.


identifier: Mobayyen, Forouzan  (2007) The organization of semantic memory : evidence from an investigation of verb semantic deficits in dementia of the alzheimer type.  PhD thesis, Concordia University.

abstract: The feature and domain-specific models of semantic memory were explored in three experiments involving ten patients with mild to moderate dementia of the Alzheimer type (DAT), and eleven age- and education-matched normal elderly controls. In Experiment 1, the living/nonliving things dissociation was examined using a confrontation-naming task comprising Snodgrass and Vanderwarts' (1980) line drawings of living (e.g., animals), and nonliving (e.g., tools) things. In Experiment 2, verb deficits in general, object/action naming dissociation, and past and present-progressive verb dissociation were explored using data from Experiment 1, and Fiez and Tranel's (1997) standardized Action Naming Test. This test comprised single and paired color pictures of actions, eliciting gerundial (e.g., baking ) and regularly inflected past-tense verbs (e.g., baked ), respectively. In Experiment 3, verb category-specific deficits were explored in a confrontation-naming task that consisted of short-movies of actions that depicted two verb categories: verbs similar in semantic and argument structure (lexical causatives; e.g., peeling ), and verbs similar in semantic content (movement verbs; e.g., crawling , and perception verbs; e.g., watching ). Four main hypotheses were examined: (1) The patients would exhibit a living/nonliving things dissociation with a selective living things deficit; (2) If the patients did exhibit an object/action naming dissociation with a selective verb deficit (e.g., Cappa et al., 1998), this dissociation would hold across two different sets of verb stimuli depicting actions: static (e.g., pictures), and dynamic (e.g., short-movies); (3) Similar to putative category specificity involving noun-labeled categories (e.g., the living/nonliving things dissociation), patients' verb deficits would also be characterized by category specificity; and (4) Following the domain-specific model, the patients' verb deficits would be characterized by a category dissociation specifically affecting the classes of movement and perception verbs; and following the feature-specific models, the patients' verb deficits would be characterized by a category dissociation, specifically affecting the class of lexical causatives. The results revealed that the patients showed a living/nonliving things dissociation with a selective living things deficit substantiating the localization assumption inherent in both domain and feature specific models. Further, when static images were used to depict verbs, both the patients and the controls had significantly more errors naming actions than objects. In contrast, when short-movies were used to depict verbs, no object/action naming dissociation was observed. These results suggested that the object/action naming dissociation observed in both the patient and control groups could have been a function of the verb stimuli (e.g., static images) used. The results further revealed that similar to their noun deficits, patients' verb deficits were also characterized by category dissociation, specifically affecting perception verbs. Patients had significantly more errors naming perception verbs than movement verbs. This dissociation was to some extent attributed to the abstract and context-dependent semantic underpinnings of perception verbs used in a referential processing task and presented to patients with global cognitive deficits. The pattern of verb category-specificity observed suggested that both semantic feature and semantic content are reflected in the organization of semantic memory with the implication that domain and feature specific models are fundamentally similar.


identifier: Scozzari, Antonino  (2007) Understanding gentrification and its implications for a revitalized St. Henri.  Masters thesis, Concordia University.

abstract: The success of neighbourhood revitalization initiatives ultimately depends on an understanding of the concerns and aspirations of resident populations and the resources available to them. The following thesis serves to advance an ethnographic approach to understanding the impacts of one form of revitalization namely, gentrification. Although often associated with negative outcomes, this study shows how gentrification may be influenced to mitigate such potential consequences. First, a review of the literature provides a better understanding of gentrification, its various forms and the characteristics of those initiating the process and their motivations for doing so. This is followed by a review of the main benefits and disadvantages of gentrification. Finally, the related literature serves to outline some of the policy orientations, which have evolved through time. The second component in this thesis centres on a specific neighbourhood study in Montreal's St. Henri district and its potential for a remediated form of revitalization. Since most of the literature has sought to study the displaced or the gentrifiers, this study uses information derived from personal interviews to evaluate the impacts of changes brought about by gentrification on the remaining residents, and their perceptions of the spatial and social relationships they have within their local environment. The thesis concludes with a consideration of how an assessment of the weaknesses and available resources in the community may inform progressive, local policies, which respect the principles of sustainability and inclusiveness and which maybe employed in future regeneration efforts.


identifier: Chen, Huafang  (2007) Residents' behaviour in community outdoor spaces in Shanghai.  Masters thesis, Concordia University.

abstract: For about 30 years since the founding of the Communist People's Republic of China, state-owned work units take responsibility for the housing for their staff as part of their welfare benefits in urban areas. After the market economy was introduced, urban housing moved toward a market-oriented approach and the real-estate sector was opened to commercial developers. Since then, the commercial market housing community has flourished in Chinese urban areas. The designs of commercial market housing communities are distinct from those of state-sponsored housing. So far, there is little literature on the influence of the new community environments on residents' behaviour within their community. This study explores whether residents have different behaviour patterns in the commercial housing communities than in state-housing and to identify the factors that influence the use of outdoor spaces in communities. Six communities are selected as case studies in the urban area of Shanghai. Quantitative as well as qualitative methods are adopted to examine the relationship between residents' behaviour and community environments. Different behaviour patterns are found. Physical environments, social and demographical factors are found to attribute to the different behaviours. Recommendations are also offered based on the findings of the study.


identifier: McDonald, Daniel  (2007) Responding to technology : Heidegger and Marcuse on thinking and acting at the technological turning.  Masters thesis, Concordia University.

abstract: Martin Heidegger's writings on modern technology are an important contribution to twentieth century philosophy. In these works, Heidegger argues that modern technology is a mode of world disclosure that reduces human beings to raw materials. Inherent in these writings are significant social implications, which emerge out of the view that human beings are reduced to raw materials under the influence of modern technology. However, these social issues remain underdeveloped in Heidegger's own work.  This thesis aims to show that Herbert Marcuse's ideas about the social implications of modern technology can be used to supplement Heidegger's writings on modern technology, in order to provide a more complete account of the social issues related to modern technology. It argues that a convergence between the two authors on the subject of modern technology can be established based on the idea that technology sets up a "world", the phenomenological understanding of modern science and the view that modern technology reduces human beings and nature to raw materials. It then proceeds to develop an enriched account of the social sphere based on the idea that modern technology reduces the political sphere to an administrative technocracy.


identifier: Benjamin, Andrea  (2007) Reconstructing the ethics of care in light of feminist insights.  Masters thesis, Concordia University.


identifier: Pagé, Anna June  (2007) Poetry in prose : Indo-European poetic language in Old Irish verbal art.  Masters thesis, Concordia University.

abstract: This thesis is intended as an examination of what 'poetic language' entails in terms of both its form and its function, particularly with respect to the Indo-European (and specifically the Old Irish) tradition. The methodology for reconstructing Proto-Indo-European is introduced, and the Indo-European poetic tradition is considered both linguistically and culturally. Both the poet and his audience participate in the poetic culture of the Indo-Europeans, and consequently both are discussed in terms of their respective degrees of competence in the poetic language; the social function and training of the poet in particular are considered. It is argued that Indo-European poetic language, and the poetic forms descended from it, define the norms of the use of language for all artistic purposes. It is shown through the analysis of poetic features in a prose passage from the Old Irish text Táin Bó Cúailnge that the language of poetry has influenced the artistic use of language so that even prose composition contains poetic features, resulting in a parapoetic style that is distinct from the stylistically less marked prose more usual in the narrative tradition.


identifier: Burton, Judith Penney  (2007) Going with the flow : the lives and work of three contemporary Canadian fibre artists.  Masters thesis, Concordia University.

abstract: This thesis recounts the stories and experiences of three contemporary Canadian fibre artists who have emerged onto the artistic scene within the past decade. It is my intent to examine the possible internal and external motivational factors involved in their choice of career path, and their choice of fibre as a medium. In-depth interviews examined the early lives of these women from their own perspectives, delving into their family and cultural influences as well as their educational experiences. Fibre artists are often involved in techniques and processes that are repetitive and extremely time consuming. The relationship between the body and the mind that occurs while engaged in this type of intensive art practice will be explored, such as: notions of flow; losing track of time; peak experiences; meditative moments; body kinaesthetic knowledge; tacit knowing; and the body memories often involved in creating with textile materials and processes. Potential links between spirituality and creative practice will be explored. Time will be considered from many angles, including: each woman's perspective on how time relates to their individual practice; how they manage time around completing such labor intensive work; and the time that it takes to become a successful fibre artist in the current artistic climate. Each artist's identification with feminism and the possible subversive nature of textiles as a medium will be explored. As well as looking at issues related to the artist's personal, public and private space, the role of place in their current art work will also be addressed.


identifier: Bonakdar, Ali  (2007) Grasping contact analysis of viscoelastic materials for design and development of an endoscopic tactile sensor.  PhD thesis, Concordia University.

abstract: In this study, analytical and Finite Element Method (FEM) are employed to determine the contact pressure on the surface of a tissue being grasped by an endoscopic grasper, in Minimally Invasive Surgery (MIS). Normally, an endoscopic grasper has corrugated teeth in order to maintain a firm grip on slippery tissues. Because it is very important to avoid damage while grasping and manipulating tissue during endoscopic surgery, it is essential to determine the exact contact pressure on the surface of the tissue. To this end, a comprehensive closed form analysis is undertaken followed by the finite element and experimental analyses of the grasping contact pressure on viscoelastic materials which have similar properties as that of biological tissues. The behavior of a grasper with wedge and semi-cylindrical teeth is examined when pressed into a linear viscoelastic material. Initially, a single tooth penetrating into a solid is studied and then is extended to the multi teeth grasper. The elastic wedge and semi-cylinder penetration is the basis of the closed form analysis. Also the effects of time are included in the equations by considering the corresponding integral operator from viscoelastic stress-stain relations. In addition, a finite element analysis is carried out. Finally, the experimental results will be presented to validate both analytical and FEM analysis. The results of this study provide a closed form expression for grasping contact pressure, force and contact area along with the variations of stress in tissue obtained through FEM analysis. The variation of contact pressure and the rate of growth of the contact area with time are also presented. In order to determine the properties of the biological tissues during MIS, we present the design, analysis, fabrication and assembly of four-tooth annular micro-fabricated tactile sensors incorporated to the upper and lower jaws of an endoscopic surgical grasper tool. Two viscoelastic models, namely, Kelvin-Voight and Kelvin are employed for tissue characterization. The relationship between the force ratio, compliance and the equivalent viscous damping of the tissue are studied. The designed sensor uses a Polyvinylidene Fluoride (PVDF) film as its sensing element. The sensor consists of arrays of rigid and compliant elements which are mounted on the tip of an endoscopic surgical grasper tool. The relative force between adjacent parts of the contact object is used to measure the viscoelastic properties.


identifier: Ah kioon, Steve  (2007) Comprehensive models and solution procedures for integrated cellular manufacturing systems design.  PhD thesis, Concordia University.

abstract: Cellular manufacturing (CM) has emerged because of the need for manufacturing organizations to supply products that require more customization and that have shorter product life cycles and times to market. This shift from mass production to demands for mid-volume and mid-variety product mixes has shown that traditional manufacturing systems relying on functional or line layouts are not efficient and flexible enough. CM is an alternate manufacturing system combining the high throughput rates of line layouts with the flexibility offered by functional layouts (job shops). The benefits include reduced set-up times, material handling, in-process inventory, better product quality and market response time. The benefits of CM can only be achieved by sufficiently incorporating the real-life structural and operational features of a manufacturing plant when creating the cellular layout. This research presents two integrated CM models, with an extensive coverage of important manufacturing structural and operational features.  The first CM model is initially formulated as a mixed integer non-linear program that incorporates multi-period production planning and dynamic system reconfiguration with deterministic production requirements. It consists of alternate process routings, the operation sequence of parts, machine duplication, machine procurement and machine capacity. Preliminary computational experiments show that only small-scale problems can be solved using the developed mixed integer non-linear program. This warrants the linearization procedures that are proposed to convert it into a linearized mixed integer programming formulation so as to solve problems of larger scale. This linearized mixed integer program is first solved using an exact solution (ES) procedure through the simplex-based branch and cut procedure of CPLEX software. Computational results are presented by solving some small-scale to large-scale numerical examples, extracted from existing literature. Although small to medium-sized problems can be solved using ES, larger ones (representing real-life sized problems) cannot be solved within reasonable computational times. A tabu search meta-heuristic is, therefore, developed to solve this mixed integer linear program. The results show that the tabu search procedure generates good quality solutions for real-life size problems within acceptable computational times.  The second model addresses the same attributes as the first one but an important extension is the introduction of routing flexibility in the system by the formation of additional alternate part process routings, called contingency routings . In addition to the alternate main process routings being created for each part type, the model forms contingency routings , which serve as backups so as to effectively address the reality of part process routing disruptions, thus allowing the cellular manufacturing system to operate in a continuous manner even in the event of any breakdowns. This enhanced model is formulated as a mixed integer linear program and is then solved using the simplex-based branch and cut procedure of CPLEX (ES). The results show that the contingency and main routings can be formed simultaneously, thus bringing enhanced system and routing flexibility. The trade-off between the increased system flexibility obtained versus the additional cost to be incurred through the formation of contingency routings for all parts is discussed by comparing the solutions obtained from the model without routing flexibility and the one with routing flexibility. It is found that the enhanced system flexibility enabled by contingency routings offsets the additional system investment costs.  Keywords : integrated cellular manufacturing systems design, mixed integer programming, linearization procedures, simplex-based branch and cut procedure, tabu search, routing flexibility, contingency routings, enhanced CM system flexibility.


identifier: Alzaman, Chaher  (2007) Modeling, analysis, and design of supply chain networks with the integration of nonlinear Cost of Quality Functions.  PhD thesis, Concordia University.

abstract: Due to the complexity of the supply chain, sourcing and distribution activities within the supply chain require a fair deal of orchestrating in order to eliminate delays and other inefficiencies. For this reason, researchers have worked effortlessly to incorporate a wide range of parameters in the modeling of the supply chain. The parameters integrated have touched many important issues. As important, issues pertaining to quality are of great importance in organizations. Some literature has discussed quality from the perspective of the supply chain and acknowledged the lack of a consistent vision pertaining to quality throughout the supply chain. With many industries today on the quest of improving their quality systems, finding ways to reduce nonconformities and failure of products is crucial. In industries such as the aerospace industry, the variable production cost is considerably high; hence producing extra parts to compensate for defectives would be a costly option. While Cost of Quality (COQ) is a very good indicator of how much poor quality is costing a company, the literature lacks a work that aims at integrating COQ into Supply Chain Network Design (SCND). This thesis aims at exploring the challenges in doing so and introduces a comprehensive supply chain model that minimizes a series of costs, in which COQ is integrated.  The inclusion of COQ is done through the integration of quadratic quality function. The overall supply chain is mathematically modeled producing a nonlinearity in the objective function and in the constraints. Hence this thesis solves a constrained binary nonlinear programming problem. Further, this work integrates binary entities, to allow for assignable/set-up costs, into the model and introduces seven solution procedures to solve the model. A real life supply chain network is used to extract relevant results. The real life supply chain is in the domain of the aerospace industry and has an n level Bill of Material (BOM). Heuristics have been introduced to solve Binary Quadratic Programming (BQP) problems before. A majority of these heuristics are geared towards unconstrained problems where feasibility might not be a concern. Alternatively in the COQ model, constraints bind the objective function making feasibility a criterion for optimality. Therefore, the seven solution procedures entertain a feasibility check mechanism and one of the seven solution procedures is a hybrid solution procedure formulated to tailor for the special topography of the feasible solution region of the problem


identifier: Bukhari, Syed Junaid Kamran  (2007) Investigation of thermal and flow fields above and below the air-water interface during natural convection.  PhD thesis, Concordia University.

abstract: Present dissertation describes the turbulent convection in horizontal layers of air and water separated by an evaporative shear-free water surface during natural convection. A detailed analysis of the hydrodynamic turbulent structure on water and air sides is presented in this study. The major portion of the research comprised of experimental investigation in addition to simulation of simultaneous airside and waterside velocity fields. The experimental measurements were made using non-intrusive state-of-the-art techniques, namely particle image velocimetry (PIV) and laser induced fluorescence (LIF) for instantaneous measurements of velocity and temperature fields, respectively.  The numerical study shows organized bulk vortical motions on air and water sides. The results also show that for unstable thermal stratification the magnitude of the airside velocities is an order of magnitude higher than the waterside velocities. The experimental results show that the water and air flow fields undergo three-dimensional flow interactions which form complex flow patterns. A detailed spectral analysis has been performed to investigate the temporal and spatial scales of turbulent motions induced during natural convection. The wavenumber and frequency spectra showed the existence of two distinct power law regimes. In low wavenumber (100 rad/m < k < 800 rad/m) and low frequency (0.06 Hz < f < 0.8 Hz) ranges, the spectra exhibit -3 slopes providing the first evidence of the existence of the buoyancy subrange in the waterside flow field during natural convection, where the energy loss is due to the work against buoyancy. At higher wavenumbers and frequencies, the inertial subrange with the classical slope of -5/3 is observed. The results also show that the scaling parameters proposed for wall-bounded natural convection are also suitable for natural convection across evaporative air-water interface.  The average temperature profiles show a characteristic boundary layer distribution in the near surface region with an extensive core of constant temperature in the bulk. The temperature profiles within the conduction layer are found to be in good agreement with previous theoretical and experimental results. The present results show z -1 dependency in the thermal source layer and z -1/3 dependency in the bulk region away from the interface which are in good agreement with the past theoretical analysis.


identifier: Sikdar, Sumit Kanti  (2007) Machinability of nickel based superalloys with carbide and ceramic tools in milling.  PhD thesis, Concordia University.

abstract: Nickel based superalloys are used in the aerospace industry for manufacturing gas turbines because of their ability to withstand large loads at high temperatures. But this property, however, makes it one of the most difficult materials to machine, necessitating frequent tool replacement due to wear and hence reduced productivity. Also, as the tool wears, the quality of the machined surface deteriorates correspondingly or may even become damaged. This thesis presents a study of how nickel-based superalloys respond to machining during a milling operation. Special consideration in this study has been given to experimental testing, accuracy and precision. Tool wear and surface roughness were investigated for Titanium Aluminum Nitride (TiAlN) coated and uncoated carbide tools under wet (coolant) and dry cutting conditions. Cutting tests were performed on a CNC milling machine to obtain tool wear and surface roughness. Average flank wear and maximum flank wear were determined by using a tool-wear measuring microscope. Surface roughness parameters were measured using a portable stylus type surface roughness tester (Mitutoyo). Based on tool wear, coated carbide tools performed better than uncoated tools and coolant further reduced tool wear and surface roughness during the cutting operation. Tool life equations were established from experimental results in order to determine tool life under wet (coolant) and dry cutting conditions. On the other hand, wear and surface roughness were also investigated for ceramic tools under different cutting conditions. Tests using ceramic tools (Whisker reinforced and Kyon 2100) were carried out under dry conditions and they performed well at high cutting speeds though the machined surface was found to deteriorate when the feed rate was high. The adhesion of workpiece material was confirmed through energy dispersive X-ray (EDX) analysis. Stability lobes were established in order to identify stable cutting conditions for nickel based superalloys. Wear mechanisms were determined under stable and unstable (chatter) conditions.


identifier: Zabihollah, Abolghassem  (2007) Analysis, design optimization and vibration suppression of smart laminated beams.  PhD thesis, Concordia University.

abstract: A general frame work is developed for the sensitivity analysis and design optimization of smart laminated composite beams with capability to suppress the vibration under random excitations. The smart structure consists of a host laminated composite beam with embedded/surface bonded piezoelectric sensors/actuators. A layerwise displacement model including the electro-mechanical coupling is utilized to account for the strong inhomogeneities through the thickness and to develop the finite element model. To perform the sensitivity analysis of the smart structure for different design parameters, analytical gradients based on developed layerwise finite element model for both static and dynamic problems are proposed. The developed sensitivity gradients provide an efficient way to predict the behavior of responses of smart structure without re-analysis.  A design optimization algorithm based on developed analytical gradients and layerwise finite element model is then developed to determine the optimal design of the smart laminated beams for a variety of objective and constraints functions, including interlaminar stresses, weight and natural frequencies.  The smart laminated beam design based on the developed optimization algorithm is used in the dynamic analysis and vibration control. An optimal control strategy, Linear Quadratic Regulator (LQR) is used to design the feedback control gain and to control the vibration response of system under deterministic loads. Effects of laminate configuration and sensor/actuator location are investigated in controlled response. An in-house experimental set-up is designed to demonstrate the performance and functionality of the proof-of-concept of smart composite beam. In many practical applications, including aerospace and automotive industries, smart laminated structures are exposed to random loading, considering this, an optimal control algorithm is developed to suppress the vibration response of the smart beam under random excitations. Different types of random loadings, including Gaussian white-noise, band limited and narrow-band excitations are investigated.


identifier: Arzpeyma, Alborz  (2007) Numerical investigation of droplet actuation via electrowetting in microchannels.  Masters thesis, Concordia University.

abstract: In Lab-on-a-chip devices (LOC), the handling of fluid droplets is one of the most important issues. Among all the ways of microactuation, electrowetting has been shown as a reliable actuation method in digital microfluidics. Its major advantages are the absence of heat generation, a rapid switching response, flexibility, and low power consumption. While most studies have been directed at performing experiments, numerical simulations of the phenomenon and its application to the design of LOCs are very few and there is still much work to do.  In the current work, a numerical study has been performed to simulate droplet behaviour under electrowetting actuation. Due to the presence of the droplet in the domain, a free surface flow problem must be solved. A Volume of Fluid (VOF) technique is applied to track the interface. In addition, due to the variable nature of the applied electric field, the relevant equation should be solved in time and space. The flow is considered laminar and Newtonian and all equations are solved in three dimensions.  Several aspects of droplet morphology are studied: contact line deformation, onset of actuation, and droplet deformation at different stages of actuation process. The droplet velocity is studied in detail and the numerical results are validated by existing experimental data in the literature. A velocity of 22 mm/s is achieved for the actuation voltage of 60 V. For design purposes, other parameters such as the electrode switching frequency and the electrode length effect on droplet velocity were also studied


identifier: Chen, Chien-Yu  (2007) Lateral-axial coupling and boundary conditioning of vibrating strings and cables.  Masters thesis, Concordia University.

abstract: Strings and cables are often used to support loads. Made of stiffer and stronger steel cables, the metal ropes find applications in heavy load bearing situations such as cable supported bridges, elevator, cable car transportation systems, and in overhead transmission line cables. Much more flexible and thin fibres, a key element in textile and optic fibre industry, are wound on high speed bobbins. In most of string and cable studies, very little attention has been given to the boundary condition that may affect their motion. In this thesis, two case studies are analyzed to study the effect of boundary condition on the string behaviour. In the first case, a string with a boundary condition in between fully clamped and free state is studied. The effect of such a partially clamped condition on the natural frequency has been tabulated. The second case investigates the axial-transverse coupled motion of a fixed-fixed string supported at two points. The nonlinearity of the tension during vibration is considered as well as the orbital motion of the excited string. The simulation of string motion is done using numerical finite difference method along with von Neumann and Courant stability conditions to ensure minimum iteration errors. Experiments are conducted by tracking the string's axial motion with a dynamic force sensor and lateral motion with a stroboscope to record the orbital behavior. In addition fast Fourier transform (FFT) has been performed on sound produced by the vibrating string to obtain the frequency spectrum


identifier: Dang, Minh Nhat  (2007) A study on two-phase flow characteristics in cross-linked microchannel heat sinks.  Masters thesis, Concordia University.

abstract: Thermal management for high performance of miniaturized electronic devices using microchannel heat sinks has recently become of interest to researchers and industry. Obtaining heat sink designs with uniform flow distribution is strongly desired. Mal-distribution in a standard straight microchannel heat sink has become a problematic issue in this research area. A cross-linking scheme, introduced in the channel core promises an appropriate solution to this problem due to flow sharing through the cross-links. In the present thesis, a number of experimental and numerical studies have been conducted to seek appropriate designs for microchannel heat sinks. The effects of cross links, introduced in the channel core of an array of parallel scaled microchannels, are investigated, by comparing the flow distribution and pressure drop in six different multi-channel configurations. A standard straight channel test section and five cross-linked test sections are experimentally investigated. All test sections have 45 parallel rectangular channels, with a hydraulic diameter of 1.59 mm. The flow distribution is monitored at four selected channels. The working mixture is air and water with superficial velocities ranging from 0.03 to 9.93 m/s, and 0.04 to 0.83 m/s, respectively. The results show that the cross-linked designs improve the flow distribution between channels compared to the standard straight channel configuration. Flow patterns obtained from flow visualization are presented in terms of fractional time function and a flow pattern map was developed. Compared with a single channel flow regime map, the expected intermittent flow regime is observed 84% to 90% of the time for the cross-linked designs, but only 65% to 80% of that for the straight channel design. A new cross-linked microchannel heat sink is proposed with the support of numerical investigations. The new design shows a significant improvement, up to 55%, on flow distribution when compared to the standard straight channel configuration without a penalty in pressure drop.


identifier: Floarea, George  (2007) XeF2 gas phase micromachininig of silicon: modeling, equipment development and verification.  Masters thesis, Concordia University.

abstract: The rapid progress in Micro-Electro Mechanical Systems necessitated the development of a micromachining technique in order to release micro-mechanical device in integrated chips. In the late 1990's there was a quest for a dry etchant that would not require an expensive setup, and overcome the problems related to wet etching, such as, stiction and etching slowdown due to bubble formation. A good alternative to wet etching would have been plasma etching, but fine tuning of the process parameters to achieve an effective control of the process, combined with the expensiveness of the equipment made plasma etching a less affordable etching method for many small labs. In gaseous phase, xenon difluoride was found to etch silicon isotropically and the required process setup is quite simple compared to other isotropic etching equipment for silicon.  In the present work, a new and computer-controlled xenon difluoride etching equipment for silicon was designed and installed. A model for the XeF 2 isotropic etching of silicon based on an atomic approach and fine tuned through pressure increase in the reaction chamber due to formation of the reaction products is presented. The shape of the etch features is predicted by a Matlab ® code, based on the developed model.  The etch depth and lateral under-etch can be calculated for a given feature and the chamber loading. The effect of concave corners is ignored in the model although the experimental results indicated a slow down etch rate at such locations.  Using the designed and fully in house built etching equipment, experiments were carried on silicon samples with square and circular mask openings in order to validate the proposed etching model. The pressure in the etching chamber was monitored during experimental work and the values were used to be used later in the Matlab ® script for verification purpose. The experimental values were compared with the theoretical ones and were found to be in good agreement.  The equipment, as designed and built, has embedded safety features required by toxic gas handling equipment codes


identifier: Hasan, Shadi  (2007) Rheology of heavy crude oil and viscosity reduction for pipeline transportation.  Masters thesis, Concordia University.

abstract: The rheological properties of heavy crude oil have been investigated using RheoStress RS100 from Haake. The effects of shear rate, temperature and oil concentration on the viscosity have been determined. From the rheological data, it was observed that blending the heavy crude oil with a limited amount of lighter crude oil worked better than using the other alternatives and was considered as the proposed method of reducing the viscosity. Therefore, the theological behavior of heavy crude oil and heavy crude oil-light crude oil (O-light) mixtures has been studied and a series of experiments was conducted. The experiments were performed in terms of studying the effect of shear stress x, shear rate Þ, yield stress x 0 , thixotropic behavior, the storage modulus G' , the loss modulus G" , the complex modulus G* , and the complex viscosity j*. The results showed a significant viscosity reduction of 0.375 Pa.s at room temperature 298 K through which it complies with the desired value required for pumping the heavy crude oil through the pipelines. Moreover, the heavy crude oil showed a thixotropic behavior with hysteresis area of 321.65 KPa.s -1 which decreases with temperature. It was clear that the heavy crude oil required a yield stress of 0.7 Pa, whereas it did not require any yield stress to pump the heavy crude oil-light crude oil mixture. In addition, it was noted that the complex modulus, the storage modulus and the loss modulus showed a direct proportional with frequency and inverse proportional with temperature. The complex viscosity of the heavy crude oil decreased with temperature and fraction of water added, and it reached 225 Pa.s at 338 K.


identifier: Movassat, Mohammad  (2007) Numerical study of primary breakup of liquid sheets.  Masters thesis, Concordia University.

abstract: The primary breakup of liquid sheets into ligaments has a great effect on the size, velocity, and penetration of the droplets produced further by the disintegration of ligaments. The generated ligaments can be categorized in two general types based on their orientation with respect to the flow field; span-wise and stream-wise ligaments. This work contains a two- and three-dimensional computational study of the primary breakup of a viscous liquid sheet. A Volume of Fluid (VOF) based code is used to solve the governing equations and capture the interface between the liquid sheet and the surrounding gas. Since the interaction between the liquid and gas is the major source of the breakup, the liquid-gas interface boundary is modified in this work and it is implemented using linear stability analysis.  The variation in the breakup time and breakup length of liquid sheets with fluid properties is investigated by a two-dimensional study. Fluid properties are stated in three non-dimensional numbers: Weber number, Ohnesorge number and the gas to liquid density ratio. The liquid surface tension shows a stabilizing effect by increasing both the breakup time and breakup length of liquid sheets. The liquid viscosity has more complicated effects; it increases the breakup length while at a certain range of Weber numbers, increasing the viscosity decreases the breakup time. Increasing the surrounding gas density decreases both breakup length and time. The study is extended to three-dimension to capture the stream-wise ligaments as well as span-wise ligaments captured in two-dimension. The effect of fluid parameters on the formation of stream-wise ligaments is presented. A mesh refinement study is conducted which demonstrates that providing at least 7 computational cells per sheet thickness would lead to results which are not dependent on the mesh size.


identifier: Shahsavari, Mohammad Reza  (2007) Flow analysis of an existing Hawker airframe using Tranair.  Masters thesis, Concordia University.

abstract: The objective of this work is to analyze an existing HAWKER airframe using a fall potential CFD code, TRANAIR, developed by Boeing. The airframe geometry is obtained by scanning an existing HAWKER 800 and is analyzed by TRANAIR solver. Full potential solvers are advantageous in CFD analyses because of fast computations and low memory requirement. The current work evaluates TRANAIR, a full potential solver with finite elements discretization using a Cartesian unstructured gridding. In addition, specific airframe simulation features as well as limitations are evaluated. Viscous TRANAIR analysis is compared with the Navier-Stokes analysis obtained from another very common CFD package, Fluent. First, a comparison is performed for DLR-F4 wing/fuselage configuration. Experimental data is used for the comparison of total lift coefficient and pressure distribution on the wing surface. TRANAIR viscous analysis by coupling the boundary layer is described and the effects of boundary layer are analyzed through a test case. The simulation on the existing HAWKER airframe is performed to evaluate the capability of TRANAIR to solve the flow over a real and complex geometry. The full configuration aircraft at cruise condition and the effects of different nacelle parameters are detailed, concentrating on aft-mounted nacelles used vastly in the business jets. Good agreement is found between TRANAIR and Navier-Stokes results. The work also demonstrates the ability of CFD to solve the flow on existing aircrafts.


identifier: Rajagopalan, Srivatsan Vengeepuram  (2007) Numerical analysis of a high velocity oxygen fuel (HVOF) process.  Masters thesis, Concordia University.

abstract: The HVOF process is used for coating protective layers on surfaces exposed to corrosion and wear. This process involves a supersonic two-phase flow of gas-solid particles. The main objective of this thesis is to explore certain key factors that influence the process efficiency such as gas-particle interactions, particle in-flight conditions, and particle loading.  To study the effect of gas-particles interactions, a Lagrangian approach which tracks individual particles in the continuous gas, is used. The supersonic gas flow leaving an HVOF nozzle is over-expanded and its adjustment to the atmospheric pressure results in shock diamonds formation, while flow impingement on a substrate results in bow-shock development. Both the shocks are responsible for affecting the particle conditions. The strength and location of bow shock vary for different substrate geometries and stand-off distances. In this work, various particle sizes impinging on different substrate configurations are simulated and the particle interactions with both the shocks are presented in detail.  To find the effect of particle loading on the gas phase, a dense particulate phase scenario is assumed. A fully Eulerian approach, which treats the particles as a fluid, is used to simulate the HVOF process and the two-phase flow characteristics were investigated for various particle loadings. The particulate phase was found to be dense near the nozzle centerline and dilute near the wall. In the particle-dense region, the gas phase characteristics were found to be severely affected, which significantly affects the particle velocity


identifier: Volovik, Regina Kneller  (2007) Accident in slow motion : inhabiting fast capitalism.  Masters thesis, Concordia University.

abstract: The proposed research argues the material origins of the virtual accident and explores its effects on temporal experiences of media consumers. Specifically, it addresses accident expressed as experiential lag, resulting from the technical imperfections of the network used to play video games. Moreover, it investigates the ways in which lag is perceived and dealt with by the players at LAN parties as well as by the artistic community. To illustrate the argument some information was included from the observation and interviews conducted during LAN-ETS 2006 and 2007, within the frame of the research project "The Social Worlds of Video Games" funded by FQRSC.  The argument develops through analysis of the temporal experiences of users of different media; examples from fine arts, movies and video games are used. The materiality of the medium along with its immediate context is found to play an important role in the medium reception. Moreover, speed at which the medium is presented is argued to be a crucial factor in initiating and maintaining the process of immersion.  Finally, the research defines lag as a social accident, and investigates how LAN parties are simultaneously a symptom and a critique of the structure of "fast capitalism"


identifier: MacDougall, Kenneth J. A  (2007) The residential school experience: residual effects upon First Nations students in their understanding and mastery of tasks within the mathematics curriculum.  Masters thesis, Concordia University.

abstract: We examine the influence of Canadian governmental policies upon the ability of First Nations students to succeed in the understanding of mathematical principles. The materials used in the task consist of mathematical curriculum (the introduction of mathematical descriptors and geometric manipulation), pre-evaluated in Quebec, and having common syllabus in British Columbia. After establishing standards of comparison with a Montreal sample population, materials are taught to two separate, small communities of First Nations students. One group attends a Band-administered institution, while the second set is subject to the regulations of the public sector.  It was assumed that there is no readily identified impediment to Aboriginal students succeeding in mathematics, beyond those that influence other normal populations. Whatever factors contributed towards the failure of Native students to maintain demographic consistency was due to external issues not relevant to the curriculum, but affecting its instruction.  Our study shows that, despite using Euro-traditional instructional methods and evaluation tools not screened for cultural bias, Aboriginal students actually fared better in the materials presented than did the comparative group. It also suggests that subsequent success becomes a function of teacher influence isolating classroom issues emanating from prior generations, and debilitating the children's learning paths. Such resistance may be overcome by non-Aboriginal teachers when they are attuned to the historical imperialism of their roots, and integrate curriculum needs with traditional Aboriginal learning methods. Further research is also required to assist teachers in isolating social behaviour from true learning, which may have application in multi-racial institutions


identifier: Gauthier, Laura  (2007) Relations between confidence and achievement in adult education students.  Masters thesis, Concordia University.

abstract: The primary aim of this thesis is: understanding to what extent gender differences in mathematics confidence persist among students of adult education, and to study the relationship between mathematics confidence and achievement within that student body. This is an important question as confidence in mathematics is central to the willingness to pursue higher mathematical studies and it is well known that women are under represented in the pure and applied sciences. Further, the study of adult students requires separate consideration in that adult students carry with them a mathematics history that often includes failures which greatly impact the adult student's mathematics confidence.  In the present study, students were asked to estimate their test results, and the difference between this estimate and the actual result is taken as indicative of mathematics confidence. Interviews were also conducted and included questions relating the student's individual 'math story', as well as a problem solving session. Results are interpreted within the theoretical framework of Autonomous Learning Behaviours as influenced by an individual's Internal Belief System, confidence being a component of the latter.  This study shows that gendered differences in confidence do persist among students of adult education with female students demonstrating less confidence than their male peers despite superior achievement. However, lesser confidence did not predict lesser achievement, whereas an excess of confidence did. Irrespective of gender, those who underestimated their grade were more likely to achieve a mean of 70% or higher. It is concluded that overconfidence compensates in part for lack of knowledge.


identifier: Muise, Sylvain  (2007) Density on elliptic curves.  Masters thesis, Concordia University.

title: Density on elliptic curves

abstract: An elliptic curve is an object that has both the analytic structure of a Riemann Surface, and the algebraic structure of a group. Under this group structure, we can consider the cyclic subgroup generated by an algebraic point on the curve, and ask whether this subgroup is dense in the complex points on the curve, under the usual topology on the analytic structure.  We give conditions on the point in question for its multiples to be dense in the complex points on the curve. We discuss transcendence results for the Weierstrass [Weierstrass p] function, analogous to results of the same nature for the regular exponential function


identifier: Ouhsain, Mohamed  (2007) Robust watermarking schemes for multimedia protection.  Masters thesis, Concordia University.

abstract: The rapid growth of digital multimedia data and the increasing use of the World Wide Web have triggered the need for the protection of multimedia contents (images, 3D graphics, audio, video). Digital watermarking has been proposed as an effective solution to the multimedia protection. The great challenge, however, is to devise efficient and robust watermarking schemes to tackle the fundamental tradeoff between robustness, data payload, and imperceptibility.  This thesis is devoted to two robust watermarking schemes that we have developed for copyright protection. The first watermarking scheme uses discrete wavelet transform (DWT) and nonnegative matrix factorization (NMF). The core idea consists of decomposing an image into four wavelet sub-bands and then applying NMF to the blocks of each sub-band, followed by an eigen-decomposition distortion step. The second watermarking scheme uses multiple parameter discrete fractional Fourier (MPDFRF) transform and DWT. The original cover image is decomposed into four wavelet sub-bands, followed by a segmentation of each sub-band into blocks. Then the MPDFRF transform is applied to each block.  The rest of the thesis is devoted to 3D mesh compression and fingerprinting. We propose a mesh compression technique using the mesh umbrella matrix. The key idea is to apply eigendecomposition to the umbrella matrix, and then retain the eigenvalues and eigenvectors which contain the low frequency coefficients. We also propose a mesh fingerprinting method by partitioning a 3D mesh into sub-meshes to produce the fingerprint vectors for all the sub-meshes


identifier: Wang, Min  (2007) Asking the right questions to elicit product requirements.  Masters thesis, Concordia University.

abstract: Eliciting precise and comprehensive product requirements from customers is of critical importance for the success of product development. In this thesis, a generic process is proposed for eliciting product requirements by asking questions generated by a linguistic analysis. The linguistic analysis is based on a graphic language called Recursive Object Model (ROM). Two types of questions are asked in the process. One is independent of the domains of product development whereas the other is based on the product domain. A generic template is developed for generating the questions and for determining the sequence of asking those questions. The answers to the questions can be sought from the customers and other partners involved in the product development, designer's own knowledge and experience, text books, dictionary, the internet, and/or the nature itself. A software prototype is developed to support the proposed process. Two case studies are used to illustrate the question generation process.


identifier: Yang, Hong Feng  (2007) Impact of Raman crosstalk and relative intensity noise transfer on RF overlay in optical passive networks.  Masters thesis, Concordia University.

abstract: In the thesis, we investigate and analyze the impact of Raman crosstalk and RIN transfer on RF video overlay channels induced by 1490-nm optical intensity modulated digital data channel, considering modulation formats of non-return-to-zero (NRZ), return-to-zero (RZ), Inverse-RZ (IRZ), and Manchester coding, fiber length, optical power, optical modulation index and fiber polarization mode dispersion (PMD).  Firstly, carrier to noise ration (CNR) degradation due to the worst and best Raman crosstalk due to the Raman crosstalk is compared for NRZ, RZ, inverse RZ and Manchester. It is found that Raman crosstalk is reduced significantly when inverse RZ or Manchester is used, in contrast to NRZ and RZ.  By comparing the result of CNR degradation in a real fiber with PMD, it is found that orthogonal polarization state setting at fiber input is still helpful in the reduction of Raman crosstalk for NRZ and RZ, but hardly for inverse RZ and Manchester, if fiber length is less than 15 km, and otherwise useless due to PMD of fiber.  Also, relative intensity noise (RIN) transfer induced CNR degradation is analyzed and is too small to be considered.


identifier: Pope, Doug  (2007) Vibrations & disruptions: a reading based on Gilles Deleuze Concerning motion in the art work of Rita Letendre, Serge Lemoyene and Claude Tousignant.  Masters thesis, Concordia University.

abstract: This thesis examines the theme of motion in art, focusing on three painters from Québec and the work they produced during the 1970s. Rita Letendre paints the motion of light, the refraction of beams, and the bending of space. Light appears in her images as something that is ever-changing, both hard and soft, fast and slow, present and absent. Claude Tousignant paints the gong-like vibration of colour waves, using contrasts of colour to divide and expand space. His work breaks down traditional concepts of stability and singularity, using polyphonic rhythms and stereo images to insist on double readings and multiple reactions. Serge Lemoyne paints movement of bodies as well as movement through bodies. Accidental streams of paint betray the artist's presence, giving his images a nervous vitality and making them appear like works in progress.  Motion brings about change and change is something people try to manipulate to their advantage, either entrenching or uprooting positions. To analyze these strategic repositions, I turn to the French philosopher, Gilles Deleuze. Several of his concepts, such as affect, Anti-Oedipus, the Body without Organs, difference and repetition, nomads, the diagram, the refrain, and deterritorialization, help to redefine the way we think about boundaries and moving bodies. These concerns coincide with explorations along similar lines by the artists in my study, artists who push at the boundaries of their medium to create questions and to expand into areas where new discoveries can be made.


identifier: Benredjem, Djamel  (2007) Contributions to cyber-forensics : processes and e-mail analysis.  Masters thesis, Concordia University.

abstract: The primary intent of this thesis is to contribute to cyber forensics by addressing two important aspects that are processes and analysis techniques. In this thesis, first, the existing proposals of cyber forensic processes are compiled and evaluated according to a priori, well-defined criteria. Beside this evaluation, a new digital forensic process is developed that uses the high potential of the previous proposals and addresses their identified deficiencies. In addition, a new technique of e-mail evidence investigation is presented to be used in cyber forensics analysis. The proposed technique extensively uses and exploits data mining techniques for answering several important questions that are extremely relevant in a forensic setting, such as e-mail clustering, classification, social network computation and the author identification of anonymous e-mails. Finally, towards this objective, the architecture and the design of an environment are also elaborated that implement the aforementioned technique.


identifier: Seib, Greg  (2007) Antler and other stories.  Masters thesis, Concordia University.

title: Antler and other stories


identifier: Hussein, Zina  (2007) Gene expression analysis in response to salt stress in wheat (triticum aestivum) and cytogenetic derivatives of wheat and the salt tolerant wheat grass, lophopyrum elongatum.  Masters thesis, Concordia University.

abstract: Comparative gene expression analysis was carried out to identify salt-stress responsive genes in T. aestivum and cytogentic stocks derived from T. aestivum x Lophopyrum elongatum crosses. A microarray consisting of 5728 cDNA amplicon probes was used in two gene expression profiling experiments. The first experiment examined the transcriptional profile of roots of the T. aestivum cultivar Norstar treated with 150 mM NaCl + 15mM CaCl 2 over a time course of 72 hours. The microarray analysis with Norstar revealed that there are 229 genes with significantly altered expression in salt treated plants. The second experiment compared gene expression profiles in wheat and wheat derivatives with different degrees of salt tolerance. Comparisons were made of roots of 150 mM NaCl + 150 mM CaCl 2 treated Chinese spring wheat, the amphiploid derived from a Chinese Spring Wheat x L elongatum cross and the disomic substitution line 3E(3A) of Chinese Spring in which chromosome 3A of wheat was replaced with chromosome 3E of L. elongatum. The analysis revealed that there are 212 genes that are significantly regulated in at least one genotype under salt stress and 42 genes have differences in regulation under salt stress between genotypes indicated by significant genotype by treatment interaction. Microarray analysis provided a practical tool for monitoring salt responsive genes in both experiments.


identifier: Claveau, C. David  (2007) A space-variant architecture for active visual target tracking.  PhD thesis, Concordia University.

abstract: An active visual target tracking system is an automatic feedback control system that can track a moving target by controlling the movement of a camera or sensor array. This kind of system is often used in applications such as automatic surveillance and human-computer interaction. The design of an effective target tracking system is challenging because the system should be able to precisely detect the fine movements of a target while still being able to detect a large range of target velocities. Achieving this in a computationally efficient manner is difficult with a conventional system architecture.  This thesis presents an architecture for an active visual target tracking system based on the idea of space-variant motion detection. In general, space-variant imaging involves the use of a non-uniform distribution of sensing elements across a sensor array, similar to how the photoreceptors in the human eye are not evenly distributed. In the proposed architecture, space-variant imaging is used to design an array of elementary motion detectors (EMDs). The EMDs are tuned in such a way as to make it possible to detect motion both precisely and over a wide range of velocities in a computationally efficient manner. The increased ranges are achieved without additional computational costs beyond the basic mechanism of motion detection. The technique is general in that it can be used with different motion detection mechanisms and the overall space-variant structure can be varied to suit a particular application.  The design of a tracking system based on a space-variant motion detection array is a difficult task. This thesis presents a method of analysis and design for such a tracking system. The method of analysis consists of superimposing a phase-plane plot of the continuous-time dynamics of the tracking system onto a map of the detection capabilities of the array of EMDs. With the help of this 'sensory-motor' plot, a simple optimization algorithm is used to design a tracking system to meet particular objectives for settling time, steady-state error and overshoot. Several simulations demonstrate the effectiveness of the method. A complete active vision system is implemented and a set of target tracking experiments are performed. Experimental results support the effectiveness of the approach


identifier: Tobin, Stephanie  (2007) The role of dopamine in acute food deprivation-induced reinstatement of heroin seeking.  Masters thesis, Concordia University.

abstract: Dopamine (DA) has been shown to play a significant role in drug reinforcement and the reinstatement of drug seeking due to priming or drug cue presentations. However, DA is suggested to play a limited role in stress-induced reinstatement, as modelled by footshock-induced reinstatement. Here the role of DA in acute food deprivation (FD)-induced reinstatement of heroin seeking, an alternative model of stress-induced reinstatement, is investigated. Rats were trained to self-administer heroin (0.05 mg/kg/infusion) for 10 days (days 1-5: 3 X 3 h sessions; days 6-10: 1 X 3 h session). Heroin-seeking behavior was extinguished by removing the drug. Following extinction, rats were tested for 48 h FD-induced reinstatement while pretreated with specific DA receptor antagonists. An attenuation of drug seeking was seen in rats given the high dose (10.0 og/kg) of the DA D 1 receptor antagonist, SCH 23390; but, not the low dose of this antagonist (5.0 og/kg) or the DA D 2 and D 3 receptor antagonists raclopride (50.0 and 100.0 og/kg) and NGB 2904 (0.1 and 5.0 mg/kg). The lack of effect for raclopride on FD-induced reinstatement was validated by demonstrating a role for this antagonist on cue-induced reinstatement of extinguished heroin seeking. These results suggest that FD-induced reinstatement may be mediated, at least in part, by the activation of the DA D 1 receptor. Moreover, since systemic injection of SCH 23390 has previously been shown to have no effect on footshock-induced reinstatement the current study suggests that DA transmission may play a differential role in footshock and FD-induced reinstatement.


identifier: Margulis, Julie S  (2007) Developing a method of measuring depression post-stroke.  Masters thesis, Concordia University.


identifier: Bhuiyan, Mohammed Imamul Hassan  (2007) Spatially-adaptive wavelet-based techniques for despeckling of synthetic aperture radar and medical ultrasound images.  PhD thesis, Concordia University.

abstract: Synthetic aperture radar (SAR) and ultrasound imaging systems are widely used for applications in remote sensing and medical diagnosis, respectively. However, the SAR and ultrasound images get corrupted by speckle noise during the process of image generation. The presence of speckle gives these images a granular appearance, thus hampering the interpretation of the image and reducing the efficiency of the algorithms in performing tasks such as compression, segmentation and classification. Hence, it is crucial to reduce the speckle from the SAR and ultrasound images before performing analysis or processing of these images.  The objective of this thesis is to develop efficient wavelet-based methods for an improved reduction of the speckle from SAR and medical ultrasound images at a reduced computational cost. It is shown that the symmetric normal inverse Gaussian (SNIG) distribution is highly suitable for modelling the wavelet coefficients of the log-transformed reflectivity. Bayesian minimum mean absolute error, minimum mean squared error and maximum a posteriori estimators are developed using the SNIG PDFs. Fast and efficient techniques are introduced to estimate the model parameters from the noisy wavelet coefficients. A fast and efficient technique is presented to calculate the Bayesian minimum mean absolute error and minimum mean squared error estimators, while closed-form expressions are obtained for the Bayesian maximum a posteriori estimators. New methods of reduced complexity are proposed to incorporate the spatial dependencies of the wavelet coefficients with the Bayesian estimation processes. Extensive simulations using synthetically-speckled, SAR and medical ultrasound images are carried out to study the performance of the proposed techniques and the results show that they perform better than several existing techniques in terms of the peak signal-to-noise ratio, speckle statistics, edge preservation index, structural similarity index, ability to suppress the speckle in the homogeneous regions and visual quality, without an undue increase in computational complexity.  Finally, it is shown that the SNIG PDF can also be used to advantage in developing an efficient method for the classical case of reducing the additive white Gaussian noise from natural images.


identifier: Trewartha, Kevin  (2007) Age-related differences in kinematic signatures of executive control of pre-potent motor responses.  Masters thesis, Concordia University.

abstract: The present study assessed traditional reaction time and accuracy as well as novel kinematic measures of younger (YA) and older (OA) adults performance on a fine motor/cognitive task using a midi keyboard and 3-D motion capture. The goal of the study was to assess the role of executive control in the production of sequential key presses that required spatial information learning. To this end, certain finger transitions were made pre-potent by manipulating their repetition frequency (presented 1, 3, or 5 times) within each trial during 3 learning blocks. These critical transitions (CT) were then used to create violation transitions (VT) presented during 3 testing blocks, that violated the pre-potent responses and required greater executive control. When learning was equated, OA were more affected in terms of reaction time by the VT than YA, suggesting that OA had more difficulty with the task when greater executive control was necessary. When key press responses were parsed into kinematic components, the results showed that OA spent more time planning their movements than YA. Crucially, when YA performed predictable CT they were found to slow down their key press execution, making smooth responses, whereas OA made rapid responses regardless of response predictability. This may be interpreted as a compensatory strategy of OA to overcome slowed movement planning. The results are discussed in terms of system-based theories of cognitive aging with an emphasis on the role of motor control processes in cognitive performance.


identifier: Tomalty, Jesse  (2007) Remedial responsibility for global poverty : individual motivation and institutional capacity.  Masters thesis, Concordia University.

abstract: Tens of thousands of people worldwide die each day from poverty-related causes. More staggering than the statistics is the fact that these deaths, and the appalling living conditions surrounding them, are avoidable yet largely ignored. Not only have concrete strategies for poverty relief and sustainable development been suggested, but their implementation would require minimal sacrifice on the part of individuals in affluent nations. The normative implications of these facts are not, however, obvious. Do the "global rich" have responsibilities of assistance towards those suffering severe deprivation? I take for granted that the global rich have what David Miller refers to as "remedial responsibility" for global poverty. That is, they have a special responsibility to contribute to remedying the situations of the worst-off. A separate but related question has to do with how remedial responsibility is to be distributed. I argue that, although several factors can contribute to the assignment of remedial responsibility, an agent's capacity to act in accordance with the requirements of remedial responsibility imposes a minimum constraint its assignment. With this in mind, I evaluate the claim that institutional agents should be treated as the primary bearers of remedial responsibility in the case of global poverty. I argue that because institutional agency depends on the motivation of individuals, the motivation of the individual constituents of an institutional agent constrain its capacity to act. In order to argue that institutional agents should be treated as the main bearers of remedial responsibility for global poverty, it must be the case that at least some of their individual constituents are sufficiently motivated to pursue the eradication of global poverty. The assignment of remedial responsibility for global poverty thus requires sensitivity to the constraints on the capacities of the potential bearers of that responsibility.


identifier: Roncero, Carlos  (2007) Comparing the online interpretation processes of metaphors and similes.  Masters thesis, Concordia University.

abstract: Metaphors take the form 'topic x is vehicle y' (e.g. life is a journey ). Similes add "like" (e.g. life is like a journey ). A reading experiment (self-paced moving-window paradigm) tested online interpretation of metaphors and similes followed by explanations; for example, John says life is (is like) a journey because it has many directions. Vehicles were read faster in metaphors than in similes. Explanations ( it has many directions ) were slower in similes than in metaphors. Frequency, but not aptness, was a predictor of reaction time; while aptness, but not frequency, was a predictor of agreement judgements. Aptness was also a more important predictor than frequency in affecting whether participants prefer a statement as a metaphor or a simile. Results are discussed in reference to Direct Statements theory (Chiappe & Kennedy, 2001), which argues that metaphors are processed like categorical statements, while similes are processed like comparison statements.


identifier: Ratto, Nicolina  (2007) The role of attachment style with mother and father in adolescents' ways of coping with a romantic break up.  Masters thesis, Concordia University.

abstract: Adolescent romantic relationships have significant implications for emotional adjustment and mental health. Thus, it is important to understand how adolescents cope with romantic loss. This study examined the extent to which middle adolescents' attachment to mothers and fathers is associated with their ways of coping with a romantic break up. A sample of 51 adolescents completed self-report measures of coping with a romantic breakup and attachment. Hierarchical regressions revealed that attachment to mother (although not father) was positively related with adolescents' ways of coping; and some of these relationships appear to be mediated by stress. As hypothesized, more anxiously attached adolescents coped by using more social support, problem solving, rumination, and confrontive behaviors. More insecurely attached adolescents in general (high on anxiety and/or avoidance dimensions) used more escape-avoidant coping. The findings underscore the importance of attachment to mother in the development of coping strategies for affect regulation in romantic relationships. Implications for prevention and interventions programs for youths are discussed.


identifier: Kashi, Arash  (2007) Rational functions and other techniques for RF and microwave modeling.  Masters thesis, Concordia University.

abstract: This thesis contributes several techniques for electromagnetic-based computer-aided modeling of microwave components exploiting rational functions, space mapping, Finite Difference Time-Domain (FDTD) method etc.  First, enhanced adaptive sampling algorithms, both in single and multi-dimensions, are proposed. The algorithms are based on rational interpolation, which leads to more accurate high-frequency models as compared to other existing interpolants, e.g. spline. Starting with a minimal number of support points, i.e. electromagnetic data, and with lowest-order rational functions, the algorithms systematically produce models, which meet user-specified accuracies. In each stage of these algorithms new support points are adaptively selected based on model errors. The advantages of the proposed algorithms are shown through practical RF and microwave examples.  Second, a new space-mapping based CAD methodology for modeling temperature characteristics of combline resonators is proposed. With the aid of two commercial simulation tools, namely Ansoft's HFSS and Agilent's ADS, this methodology gener ates accurate temperature models of combline resonators. The method is generic i.e. it is capable of generating corresponding models for a variety of resonator structures including the mushroom and straight. The model generated using space mapping is suitable for compensation methods where the type of material to be used has yet to be determined.  Third, a FDTD based technique, integrated with rational functions has been developed to generate fast and accurate temperature models for combline resonators. Through examples, it has been shown that a FDTD algorithm with 2D uniform-grid distribution is fully capable of modeling temperature behavior of combline resonators. The advantage of this work over other numerical solutions in terms of computational complicity and required simulation time is illustrated. This technique can be applied to compensation methods requiring geometry optimization.


identifier: Harbin, Ami  (2007) Ownmost responsibility : singularity, relationality and caregiving.  Masters thesis, Concordia University.

abstract: This thesis centres on the following question: What are the necessary conditions of persons becoming able to act as responsible selves?  My attempt to answer this question proceeds by means of direct engagement with two schools of philosophical thought relevant to the issues at hand, Heideggerian and feminist theory, respectively. The thesis focuses in particular on Heidegger's account of authenticity, singularization and responsibility, and relationality accounts' emphases on both the importance of interdependent relationships of care and potential problems with overly individualistic accounts of the self. I argue that the Heideggerian notion of singularization should be seen as a necessary precondition of responsibility, while Heidegger's account of care for others is ultimately an unsatisfying one, as it constitutes what I term a caretaking. I then argue that the relational accounts' presentation of one's need for care from others should be maintained in an adequate account of responsibility, while criticizing these views for what I call an over-problematization of the notion of the individual.  My own account of the responsible self maintains both singularization and relationality, in the manners I characterize them here, as necessary conditions of one's ability to be responsible, and I argue that responsible caregiving for particular others should be seen as one way of enacting responsibility so conceived


identifier: Seirafianpour, Nader  (2007) Study of nanoparticles of SnO2 on Au and nanoparticles of TiO2 on Ag for plasmonic applications.  Masters thesis, Concordia University.

abstract: Nanolayered systems composed of a gold film coated by a granular tin dioxide layer, and a silver film coated by a granular layer of titanium dioxide are fabricated by combined sputtering/sol-gel methods. The conditions of the sol-gel synthesis and the substrate materials were adjusted with a particular attention to the aggregation effects, especially in the case of the gold/tin dioxide system. The dielectric particles are uniformly distributed on the metal surfaces and the films are smooth (mean roughness less than 6 nm). The components of the nanolayered systems prepared in this work are found to be crystalline and the sputtered metal is preferentially oriented on the substrate. Because of the low-temperature sol-gel method used for the synthesis, especially small (4-5 nm) crystallites of titanium dioxide (anatase allotropic phase) have been found with a narrow size distribution. Size and intensity enhancement effects have been evidenced in both systems and studied by micro-Raman spectroscopy.  A particular attention is paid in this work to the optical properties of the nanolayered composites with an emphasis on the surface plasmon resonance. The near-normal reflection spectra are measured and the effect of the dielectric coating on both the surface plasmon band of the noble metal and the band gap absorption of the dielectric are investigated. The effective-medium theory is used to calculate the reflection curves. The simulated curves show a qualitative agreement with the experimental spectra. The possibility to use these systems in sensing applications is discussed.


identifier: Koerner-Singh, Naomi  (2007) Cognitive vulnerability to excessive worry and its relationship to the processing of uncertainty.  PhD thesis, Concordia University.

abstract: Numerous studies have shown that clinically-significant anxiety is associated with a tendency to apply threat interpretations to stimuli or situations that can plausibly be interpreted in a neutral or benign fashion. Current thinking suggests that biases in appraisal and interpretation are not merely epiphenomena of disorder; but rather, markers and "transmitters" of underlying cognitive vulnerability. Intolerance of uncertainty has been identified as a potential cognitive vulnerability for generalized anxiety disorder (GAD), a condition characterized by excessive and uncontrollable worry. Individuals who endorse high levels of intolerance of uncertainty hold the view that uncertainty is stressful and upsetting; that uncertainty leads to the inability to take action; that uncertain events are negative and to be avoided; and that being uncertain is unfair. This thesis consists of three independent investigations of the relationship of intolerance of uncertainty to the processing of uncertainty. Using three different paradigms, individuals low and high on intolerance of uncertainty were compared on their appraisals of ambiguous scenarios. Collectively, the findings suggest (1) that individuals high on intolerance of uncertainty appraise ambiguous stimuli and events as less pleasant and more disconcerting relative to individuals low on intolerance of uncertainty; (2) that individuals with high levels of intolerance of uncertainty take longer to evaluate affectively-neutral stimuli compared to individuals with low levels of intolerance of uncertainty; (3) that degree of intolerance of uncertainty is a stronger predictor of appraisals of ambiguous situations than are GAD symptoms and mood variables; (4) that appraisals of ambiguous situations partly mediate the relationship of intolerance of uncertainty to worry; (5) that the appraisals of individuals high on intolerance of uncertainty appear to lack content-specificity; (6) that relative to individuals low on intolerance of uncertainty, those high on intolerance of uncertainty have a greater tendency to use anxious affect as information when appraising potentially threatening situations; and (7) that habitual use of thought suppression is associated with negative appraisals of ambiguous scenarios in individuals high on intolerance of uncertainty only. The findings are discussed within the context of conceptual models of worry and GAD as well as theories of normative decision-making under uncertainty.