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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
819991

Mechanical and Hydromechanical Behavior of Host Sedimentary Rocks for Deep Geological Repository for Nuclear Wastes

Abdi, Hadj 16 April 2014 (has links)
Sedimentary rocks are characterized with very low permeability (in the order of 10-22 m2), low diffusivity, a possible self-healing of fractures, and a good capacity to retard radionuclide transport. In recent years, sedimentary rocks are investigated by many research groups for their suitability for the disposal of radioactive waste. Development of deep geologic repositories (DGRs) for the storage of radioactive waste within these formations causes progressive modification to the state of stress, to the groundwater regime, and to the chemistry of the rock mass. Thermal effects due to the ongoing nuclear activity can cause additional disturbances to the system. All these changes in the system are coupled and time-dependent processes. These coupled processes can result in the development of an excavation damaged zone (EDZ) around excavations. More permeable than the undisturbed rock, the EDZ is likely to be a preferential pathway for water and gas flow. Consequently, the EDZ could be a potential exit pathway for the radioactive waste to biosphere. An investigation of the Hydraulic-Mechanical (HM) and Thermal-Hydraulic-Mechanical-Chemical (THMC) behaviour of sedimentary rock formations is essential for the development of DGRs within such formations. This research work consists of (1) an experimental investigation of the mechanical behaviour of the anisotropic Tournemire argillite, (2) modeling of the mechanical behaviour of the Tournemire argillite, and (3) numerical simulations of the mechanical and hydromechanical behavior of two host sedimentary rocks, the Tournemire argillite and Cobourg limestone, for deep geological repository for nuclear wastes. The experimental program includes the measurements of the physical properties of the Tournemire argillite and its mechanical response to loading during uniaxial compression tests, triaxial compression tests with different confining pressures, unconfined and confined cyclic compression tests, Brazilian tests, and creep tests. Also, acoustic emission events are recorded to detect the initiation and propagation of microcracks within the rock during the uniaxial testing. The approach for modeling the mechanical behaviour of the Tournemire argillite consists of four components: elastic properties of the argillite, a damage model, the proposed concept of mobilized strength parameters, and the classical theory of elastoplasticity. The combination of the four components results in an elastoplastic-damage model for describing the mechanical behaviour of the Tournemire argillite. The capabilities of the model are evaluated by simulating laboratory experiments. Numerical simulations consist of: (1) a numerical simulation of a mine-by-test experiment at the Tournemire site (France), and (2) numerical simulations of the mechanical and hydromechanical behaviour of the Cobourg limestone within the EDZ (Canada). The parameters influencing the initiation and evolution of EDZ over time in sedimentary rocks are discussed.
819992

Calcium Signaling During Polar Body Emission in the Xenopus laevis Oocyte

Leblanc, Julie 16 April 2014 (has links)
Polar body emission (PBE), a form of asymmetric division, occurs twice during vertebrate oocyte maturation and is required to produce a haploid egg for sexual reproduction. Our lab elucidated parts of the mechanism that regulates PBE in Xenopus laevis oocytes. Cdc42 and RhoA, two GTPases, were shown to mediate membrane protrusion and the contractile ring, respectively. It is believed that cdc42 is mediating the protrusion by regulating actin polymerization. However, it is not clear what upstream signaling pathway regulates cdc42 activation during PBE. One possibility is calcium signaling, which occurs at fertilization, and is required for second PBE. Interestingly, the fertilization calcium transient also regulates cortical granule exocytosis/membrane retrieval, a process that also involves cdc42-mediated actin assembly. Furthermore, active cdc42 and RhoA are found in non-overlapping concentric zones in single-cell wound healing; their activation requires calcium signaling. To determine possible calcium transients during polar body emission, we employed the calcium-binding C2 domain of PKCβ in live cell imaging. Surprisingly, the most prominent C2 signal was seen after cdc42 activation and membrane protrusion. Co-localization experiments indicated that the C2 signal appeared at the cortical area marked by the contractile ring component anillin, and after partial constriction of the ring. Injection of the calcium chelator, dibromo-BAPTA, abolished the C2 signal, suggesting that it is indeed depicting a calcium transient. Dibromo-BAPTA injection also inhibited polar body abscission, as assessed by a novel abscission assay developed in our lab. We have for the first time detected a calcium signal during PBE that is essential to the last step of cytokinesis—abscission.
819993

Eloping Prevention, Occupancy Detection and Localizing System for Smart Healthcare Applications

Roshan, Muhammad Hassan Ahmad 16 April 2014 (has links)
The purpose of this thesis is to devise a system based on RFID (Radio Frequency IDentification) that can be used for smart healthcare applications. Location estimation, eloping prevention and occupancy detection are monitoring applications of smart healthcare which can provide very useful information for the nursing and administration staff of the nursing-home/hospital. The introduction of ubiquitous networking along with the concepts such as Internet of Things (IoT) can certainly help achieve the goals of smart healthcare. RFID technology has features, such as low power and small size, which makes this technology suitable for researching solutions for smart healthcare. Today several nursing-home/hospital monitoring solutions exist in the market and academia alike. The solutions marketed commercially are very expensive whereas the solutions from academia provides solutions to isolated problems but a comprehensive all in one solution that can meet the need of smart healthcare monitoring applications is missing. In this thesis we present a system that is low cost and suitable for accommodating a number of the smart healthcare applications including occupancy detection, location estimation, eloping prevention and access control. The solution is implemented on a customized Openbeacon Active RFID System (OARS). Active RFID based proximity detection is the core of our system. Practical experiments based on novel Proximity Detection based Weighted Centroid Localization (PD-WCL) method were done to analyze the performance of the system with different applications to highlight the applicability of the system.
819994

Impulsive Differential Equations with Applications to Infectious Diseases

Miron, Rachelle 17 April 2014 (has links)
Impulsive differential equations are useful for modelling certain biological events. We present three biological applications showing the use of impulsive differential equations in real-world problems. We also look at the effects of stability on a reduced two-dimensional impulsive HIV system. The first application is a system describing HIV induction-maintenance therapy, which shows how the solution to an impulsive system is used in order to find biological results (adherence, etc). A second application is an HIV system describing the interaction between T-cells, virus and drugs. Stability of the system is determined for a fixed drug level in three specific regions: low, intermediate and high drug levels. Numerical simulations show the effects of varying drug levels on the stability of a system by including an impulse. We reduce these two models to a two-dimensional impulsive model. We show analytically the existence and uniqueness of T-periodic solutions, and show how stability changes when varying the immune response rate, the impulses and a certain nonlinear infection term. The third application shows how seasonal changes can be incorporated into an impulsive differential system of Rift Valley Fever, and looks at how stability may differ when impulses are included. The analysis of impulsive differential systems is crucial in developing more realistic mathematical models for infectious diseases.
819995

Modeling and Performance Analysis of Distributed Systems with Collaboration Behaviour Diagrams

Israr, Toqeer 23 April 2014 (has links)
The use of distributed systems, involving multiple components, has become a common industry practice. However, modeling the behaviour of such systems is a challenge, especially when the behavior consists of several collaborations of different parties, each involving possibly several starting (input) and ending (output) events of the involved components. Furthermore, the global behavior should be described as a composition of several sub-behaviours, in the following called collaborations, and each collaboration may be further decomposed into several sub-collaborations. We assume that the performance of the elementary sub-collaborations is known, and that the performance of the global behavior should be determined from the performance of the contained elementary collaborations and the form of the composition. A collaboration, in this thesis, is characterized by a partial order of input and output events, and the performance of the collaboration is defined by the minimum delays required for a given output event with respect to an input event. This is a generalization of the semantics of UML Activities, where all input events are assumed to occur at the same time, and all output events occur at the same time. We give a semantic definition of the dynamic behavior of composed collaborations using the composition operators for control flow from UML Activity diagrams, in terms of partial order relationships among the involved input and output events. Based on these semantics, we provide formulas for calculating the performance of composed collaborations in terms of the performance of the sub-collaborations, where each delay is characterized by (a) a fixed value, (b) a range of values, and (c) a distribution (in the case of stochastic behaviours). We also propose approximations for the case of stochastic behavior with Normal distributions, and discuss the expected errors that may be introduced due to ignoring of shared resources or possible dependencies in the case of stochastic behaviours. A tool has been developed for evaluating the performance of complex collaborations, and examples and case studies are discussed to illustrate the applicability of the performance analysis and the visual notation which we introduced for representing the partial-order relationships of the input and output events.
819996

The Sex Trafficking of Women into Canada: Exploring the Government’s Approach to Prevention, Protection, and Prosecution

O'Dell, Melanie 23 April 2014 (has links)
In 2002, Canada ratified the United Nations Protocol to Prevent, Suppress and Punish Trafficking in Persons, especially Women and Children. Nearly a decade later, it released its first National Action Plan to Combat Human Trafficking, designated a government-led task force, and approved a budget specifically allocated for human trafficking initiatives and programming. The main objective of this thesis is to determine the kind of approach the Government of Canada has implemented to address the issue of international sex trafficking into Canada, to determine whether anything is exempted or neglected from this approach, and to explore what this could mean for victims of sex trafficking. I use a qualitative narrative analysis of the Canadian government’s publications on the issue of human trafficking including policy, programming, and research-related documents. The findings reveal that Canada has implemented an approach which emphasizes the safety and security of the country which is indicative of a narrative that frames international sex trafficking as a threat. These findings further reveal a negative impact of such framing on trafficking victims. In employing an approach which prioritizes the safety and security of the state, Canada neglects the notion that human trafficking violates a person’s human rights, overlooks a consideration of the root causes of trafficking, and under-prioritizes the notion of ‘victim’ despite the phenomenon continuing to produce new victims each year in Canada.
819997

Developing Microfluidic Volume Sensors for Cell Sorting and Cell Growth Monitoring

Riordon, Jason A. 28 April 2014 (has links)
Microfluidics has seen an explosion in growth in the past few years, providing researchers with new and exciting lab-on-chip platforms with which to perform a wide variety of biological and biochemical experiments. In this work, a volume quantification tool is developed, demonstrating the ability to measure the volume of individual cells at high resolution and while enabling microfluidic sample manipulations. Care is taken to maximise measurement sensitivity, range and accuracy, though novel use of buoyancy and dynamically tunable microchannels. This first demonstration of a microfluidic tunable volume sensor meant volume sensing over a much wider range, enabling the detection of ̴ 1 µm3 E.coli that would otherwise go undetected. Software was written that enables pressure-driven flow control on the scale of individual cells, which is used to great success in (a) sorting cells based on size measurement and (b) monitoring the growth of cells. While there are a number of macroscopic techniques capable of sorting cells, microscopic lab-on-chip equivalents have only recently started to emerge. In this work, a label-free, volume sensor operating at high resolution is used in conjunction with pressure-driven flow control to actively extract particle/cell subpopulations. Next, a microfluidic growth monitoring device is demonstrated, whereby a cell is flowed back and forth through a volume sensor. The integration of sieve valves allows cell media to be quickly exchanged. The combination of dynamic trapping and rapid media exchange is an important technological contribution to the field, one that opens the door to studies focusing on cell volumetric response to drugs and environmental stimuli. This technology was designed and fabricated in-house using soft lithography techniques readily available in most biotechnology labs. The main thesis body contains four scientific articles that detail this work (Chapters 2-5), all published in peer-reviewed scientific journals. These are preceded by an introductory chapter which provides an overview to the theory underlying this work, in particular the non-intuitive physics at the microscale and the Coulter principle.
819998

Becoming Evangelical in Rural Costa Rica: A Study of Religious Conversion and Evangelical Faith and Practice

Epp, Jared M.H. 28 April 2014 (has links)
Almost daily emotional worship pours from a warehouse-sized evangelical church in the small rural community of Santa Cruz, Costa Rica. Within twenty years an evangelical presence has gone from virtually non-existent to standing alongside the Catholic Church in the area’s religious landscape. Scenarios like this are going on throughout Latin America as evangelical faith has become firmly rooted in the region. In this thesis I provide another ethnographic research context to the growing body of literature focused on Pentecostalism/evangelicalism in Latin America. Like others addressing this dynamic, I explore the factors and motivations that lead people to become evangelical. I approach these questions with particular emphasis on the characteristics of evangelical faith as it is constructed and practiced during church services. Through participant observation during church services and interviews with practicing evangelicals in and around Santa Cruz, I highlight the relationship between the characteristics of an evangelical faith and the factors and motivations that lead people to seek it. To be religiously active in the manner of my informants requires deep commitment and is not a faith adopted and practiced lightly. Those who become evangelical and sustain the demanding practice are likely to seek it for spiritual solutions to difficult life situations.
819999

A Framework for Monitoring and Adapting Business Processes Using Aspect-Oriented URN

Pourshahid, Alireza 28 April 2014 (has links)
Context: Organizations strive to improve their business processes, and adaptive business processes have recently attracted much attention in that context. However, much research in that area has a narrow focus and does not consider a comprehensive view of the organization and its goals. In addition, Business Intelligence-based monitoring methods are useful for business process improvement but they often present information in a format that is not entirely suited for decision making. Objectives: The main objectives of this thesis are to provide: • A framework to model goals, processes, performance, situations, and improvement patterns using one modeling notation, in an iterative and incremental manner; • A method for the modeling and analysis of cause-effect relationships between indicators used to measure goal satisfaction; and • A technique allowing the detection of undesirable, sub-optimal conditions and the application of improvement patterns to the context Method: We develop an iterative framework based on the User Requirements Notation (URN) for modeling, monitoring and improving business organizations and their business processes. In addition, we introduce a formula-based evaluation algorithm allowing better analysis of the relationships between the business performance model elements (namely indicators). Furthermore, we use a profiled version of the Aspect-oriented URN (AoURN) with extensions (Business Process Pattern profile), for detecting undesirable conditions and for business process adaptation. We validate the novelty and feasibility of our approach by performing a systematic literature review, by assessing it against Zellner’ mandatory elements of a method, by developing tool support, by performing a pilot experiment and by using real-life examples from different sectors (healthcare and retail). Results: The two examples show that through the framework’s iterative approach, organizations at different levels of maturity in their business improvement journey can benefit from the framework. Furthermore, our systematic literature review shows that although there are existing works that enable our vision, most of them have a narrow focus and do not cover the three organization views that are of interest in this research. AoURN allows analysts to find repeated patterns in a context and bundle goal, performance and process models as a self-contained unit. AoURN hence enables the modeling of complex circumstances together with analysis techniques for what-if analysis and process adaptation, all using a unified and integrated modeling language. Finally, the pilot experiment suggests that, with some level of documentation and training, users who are already familiar with URN can use the profiled AoURN provided in this thesis as well as the discussed improvement patterns.
820000

Using Outcome-Based Instructional Design Approach to Enhance E-Learning with Social Software: A Mixed Methods Case Study

Sun, Rong 28 April 2014 (has links)
This mixed-methods single case study explored how outcome-based instructional design can be used to incorporate social software into an existing e-learning course. Pre-service teachers enrolled in a teacher education program at a Canadian university volunteered to participate in a study where social software was incorporated into a foundations course to facilitate digital literacy development, social objects production, and reflection on how these experiences connect to future teaching practice. The instructional design process was guided by a conceptual framework and informed by W(e)Learn, a well-tested e-learning design and evaluation framework. The quantitative and qualitative data were collected from the instructional designer’s journal, participant surveys, course records and interviews. Findings provided a comprehensive view of the effectiveness of outcome-based instructional design. In general, participants achieved the expected learning outcomes for this study. There were also unexpected outcomes. For example, some learners created a virtual community of practice. Some learners had an influence on their in-service teacher’s use of social software in teaching and learning. The findings supported the literature that states an outcome-based instructional design approach can facilitate learning. The findings also revealed why participants used social software in their teaching (e.g. awareness, usefulness, and school environment). In addition, these findings can inform school board policy with regard to supporting the use of social software in teaching and learning. The integration of qualitative and quantitative findings revealed convergence and divergence between the two types of data. In addition the findings informed directions for further research, including the relationship between learners’ satisfaction and learning experiences as well as the achievement of learning outcomes. The corroboration of data also identified specific effective and iii imperfect areas of the instructional design strategies, which, in turn, informed the revision of the conceptual framework for outcome-based instructional design. This study found W(e)learn to be effective in guiding outcome-based instructional design and analyzing the achievement of expected learning outcomes. The study also contributes to theory by recommending the inclusion of two new elements into W(e)learn. Painstakingly recording the instructional design process in a journal resulted in documented practical information and lessons learned that may guide and benefit instructional designers and educators who want to incorporate software into their learning activities.

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