Search Constraints

Start Over
Filtering by: Language English Remove constraint Language: English Publisher Carleton University Remove constraint Publisher: Carleton University

Search Results

  • Role of TrkB.T1 in Glial Inflammatory Response Elicited by MHV

    Resource Type:
    Thesis
    Creator:
    Heiratifar, Noora Donna
    Abstract:
    In the present thesis, we used a rodent analogous coronavirus, murine hepatitis virus (MHV), in culture to directly assess its impact on astrocytic and microglial cells. Given the increasing importance of the brain neurotrophic factor (BDNF)-TrkB signaling system in glial functioning, we also assessed whether the unique TrkB.T1 truncated isoform (the only BDNF receptor on astrocytes) would modulate glial reactivity to MHV viral infection. Our results largely support the notion that MHV readily infects astrocytes and caused a degree of toxicity of these cells. The addition of microglia to the astrocytic culture modulated the magnitude of this effect and greatly increased pro-inflammatory cytokine release. Furthermore, TrkB.T1 deficiency appeared to greatly reduce astrocyte viability and microglial morphology. These data may have useful implications for better understanding the nature of glial responses to coronaviral infection and the importance of TrkB in such responses.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Neuroscience
    Date Created:
    2023

  • Towards a critique of state secrecy: Uncovering the rhetorical practices of secret keepers and their legitimization by the discourse of law

    Resource Type:
    Thesis
    Creator:
    Lefebvre, Stephane
    Abstract:
    This thesis examines the rhetorical devices that secret keepers in Canada, the United Kingdom and the United States use to justify the non-disclosure of state secrets. It also examines the manner in which judges in these three countries write and speak about state secrets. By embracing the rhetorical devices used by secret keepers and materializing them in reported decisions, judges add legitimacy to the discourse of secret keepers and directly assist in its reproduction and distribution. Taken together, the discourse of the state and the discourse of law on state secrecy sets up the dominant interpretive frames with which any public engagement, whether supportive or critical, must engage. While the persuasive social effect and perceived legitimacy of this combined discourse may ebb and flow, it appears enduring and difficult to challenge despite the existence of counter-discourses and concessions such as the adoption of access to information legislation. This thesis seeks to understand how state secrecy discourse becomes or appears preeminent, and how it reproduces itself, as a first step in formulating a fuller critique of this discourse.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Legal Studies
    Date Created:
    2023

  • Modular Verification of Hierarchical Component-Based Software Systems

    Resource Type:
    Thesis
    Creator:
    Baak, James Alec William
    Abstract:
    Using Component-based Software Engineering approaches with Formal Methods has seen an influx of interest in the recent decades. The joining of these two disciplines have been stifled though due to unclear component specifications and expensive formal verification techniques, which hurt the reusability and scalability of complex software systems. In this work, we expand on current component-port-connector metamodels for formally specifying a system's architectural and behavioural requirements into a hierarchical component system structure by using abstract Composite Components. The Composite Components of a system model can then utilize modular verification for isolating the verification process into modules surrounding Composite Components and generating higher level properties. We formalize our metamodel in Alloy 6 and present a template for specifying system properties for modular verification which enables the reuse of previous verification efforts on satisfied modules. We conclude with an example case study system and analysis of the modular verification strategy.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2023

  • Analysis of Open-Source Data in Wind Power Prediction Modeling

    Resource Type:
    Thesis
    Creator:
    von Zuben, Elizabeth Lynn
    Abstract:
    As identified in the 2021 IPCC AR6 WGIII report, wind energy has a high potential to reduce greenhouse gas emissions. The deployment of wind energy, however, has fallen behind its potential in part because of the need for improved wind power predictions. This thesis combines historical power production data, meteorological station data, reanalysis data, and numerical weather prediction output data (WRF model) to determine the optimal combination of data sources and variables for wind power prediction using a random forests model. A study then further evaluates reanalysis data and methods of bias correction for this type of data, to improve power predictions at 52 wind farms across Canada using power curve and machine learning methods. Recommendations are proposed for: the use of data sources and important input variables; the utility of global reanalysis data sources by terrain features; and the utility of bias correction methods for downstream wind power prediction.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Mechanical
    Date Created:
    2022

  • A NUMERICAL STUDY OF THE IMPACT OF MAKE-UP AIR VELOCITY ON THE SMOKE CONDITIONS IN AN ATRIUM

    Resource Type:
    Thesis
    Creator:
    Boakyewah, Barbara
    Abstract:
    This research numerically investigates the effect of make-up air on the smoke conditions in an atrium under different make-up air velocities and fire sizes. A total of twenty-four (24) simulations were conducted using the Fire Dynamics Simulator (FDS) to consider different scenarios of fire located at the center (axisymmetric), northwest corner and southeast corner of the atrium. Fire sizes of 1 MW, 3 MW and 5 MW along with different make-up air velocities of 1 m/s, 1.5 m/s, 2.5 m/s and 3.5 m/s were simulated to investigate their effect on smoke conditions the atrium. The results showed that the simulation predicted slightly higher temperatures and lower smoke layer heights when compared to the experimental tests. The position of the fire source at different locations showed different and increasing temperatures when the velocity changes from 1 m/s to 3.5 m/s, however the effects of make-up air velocities were minor.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Civil
    Date Created:
    2023

  • A Web Based Architecture to Operationalize Geospatial Simulation Environments

    Resource Type:
    Thesis
    Creator:
    St-Aubin, Bruno
    Abstract:
    Simulation is inherently multi-disciplinary. It requires knowledge about the system under study, expertise in simulation theory to define models and programming skills to implement models. Geospatial simulation requires an additional layer of expertise in topology, geospatial data structures, spatial analysis, computational geometry, and other related topics. Commercial modeling and simulation software can be used to provide an environment to facilitate simulation studies for users. However, these software tend to be narrowly scoped to specific business applications and tightly couple model and simulator. As such, it is difficult to expand their usage and reuse them outside of the application domain they were intended for. The Discrete Event System Specification (DEVS) is a modular and hierarchical simulation formalism that clearly separates the model, simulator and experiments. It can be used break down the disciplinary silos within which single-use simulators are built and allow users to study real-world systems from a broad range of application domains. In this research, we present an architecture that facilitates the operationalization of DEVS based, geospatial simulation environments in multidisciplinary projects. The architecture relies on a clear definition of roles and responsibilities to leverage the different skillsets in an organization. It considers a series of business processes for modelers, subject matter experts, web developers and end users. It relies on a web-based architecture to provide simulation as a service capability and support users across the entire simulation lifecycle. It seeks to democratize DEVS simulation by making use of the strengths and skills available in larger organizations and by providing the necessary tools for collaboration. Importantly, it preserves key features of DEVS (genericity, modularity, flexibility, etc.) and encourages users to follow best practices in model documentation to foster model reusability and improve model discoverability. It relies on modeling and simulation as a service to overcome technological barriers of entry for DEVS simulation and provide a set of reusable tools to design simulation-based, web applications for end users.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2023

  • QoS Performance Measurement Through SRv6 Network Programming for Smart City IoT Traffic

    Resource Type:
    Thesis
    Creator:
    Kuri, Sajib Kumar
    Abstract:
    Segment Routing over IPv6, also known as SRv6, is a modern networking solution that aims to improve the current Internet of Things (IoT) network's reliability, availability, and scalability. Performance measures are required to evaluate SRv6 behaviors or functions. The proposed work aims to provide real IoT traffic profiles to assess the performance of SRv6 behaviors. In particular, a three-module SRv6 programming model is proposed to measure the performance of SRv6 policy headend and endpoint behavior and ensure reliability and quality of service (QoS). Moreover, a novel finder algorithm for maximum receive rate (MRR) benchmarking is proposed, which can outperform existing techniques in terms of throughput/bandwidth performance while maintaining the same computational resources. Finally, implementation results provide insights into forwarding different IoT use-cases traffic based on the functional service requirements. That also ensures a higher usage level of existing IoT networks, minimizing the need for additional capacity and lowering network costs.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2022

  • Constrained Geometric Optimization Problems

    Resource Type:
    Thesis
    Creator:
    D'Angelo, Anthony Mark
    Abstract:
    In this thesis we consider constrained geometric optimization problems. The first is a constrained version of the k-Steiner tree problem restricting the Steiner points to lie on a restricted set of curves. We solve the 1-Steiner tree problem in the Euclidean plane in optimal asymptotic time and space bounds when the Steiner point is constrained to lie on an input line. We then show how existing results can be used to generalize the result. The second problem is the smallest k-enclosing disc problem for a point set S contained in a simple polygon. In this problem we work with geodesic discs, meaning we use the geodesic distance function (i.e., the length of the shortest path). We present both a 2-approximation algorithm and an algorithm that finds the optimal radius for the smallest k-enclosing geodesic disc of a set of points inside a simple polygon. The last problem we consider is the smallest k-enclosing geodesic disc problem for a set of points in a simple polygon when the computed disc must be centred on an input chord of the polygon.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Computer Science
    Date Created:
    2023

  • Assessing the Beclin-1 Knockout: Autophagy, Neurogenesis, and the TUNL Task

    Resource Type:
    Thesis
    Creator:
    Bornheimer, Jacob
    Abstract:
    Autophagy is the intracellular process of isolating, enveloping, and recycling cell matter. Beclin-1 is a protein that acts as a lynchpin in the autophagic process. Animals lacking Beclin-1 are embryonically lethal, and knockout of Beclin-1 causes a reduction in adult hippocampal neurogenesis. The dentate gyrus (DG) is normally home to ongoing neurogenesis, which is thought to mediate pattern separation and memory encoding. First, I test a new protocol for the TUNL task. To assess whether a behavioural phenotype of Beclin-1 nKO is apparent, on the second experiment I compare TUNL performance between WT and KO mice. The new protocol for the TUNL task produces a reliable measure of pattern separation. Beclin-1 nKO reduced DG neurogenesis by 40% compared to WT. No difference between the WT and KO mice in TUNL task performance (pattern separation ability) was found but KO mice had lower activity in the CA1 during the task.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Neuroscience
    Date Created:
    2023

  • Optimal Selection of IPsec-Based Security Mechanisms in Resource Constrained IoT Environment

    Resource Type:
    Thesis
    Creator:
    Mahmoud, Abdullah Fahmi Mustafa
    Abstract:
    Internet of Things (IoT) is a modern-day technology that supports many different applications such as smart cities, e-health, and smart homes. However, the specific IoT nature of connecting various heterogeneous devices complicates the implementation of conventional security mechanisms. In this work, a device-based security approach has been proposed to assign optimal security mechanisms to the set of heterogeneous IoT devices based on their available resources and the system requirements. To achieve the proposed approach, the security overhead equation was formulated to include 3 parameters: RAM usage, energy consumption and throughput. A hardware implementation was used to measure these parameters and to calculate the security overhead for the tested security mechanisms. The Pareto frontline was used to select the optimal security mechanism that minimizes the security overhead per device while maximizing the system requirement. The selection algorithm was tested in a simulation of 50 heterogeneous devices that ran 30 security mechanisms.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2023