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On Reducing Underutilization of Security Standards by Deriving Actionable Rules: An Application to IoT
Get PDFEven though there exist a number of security guidelines and recommendations from various worldwide standardization authorities (e.g., NIST, ISO, ENISA), it is evident from many of the recent attacks that these standards are not strictly followed in the implementation of real-world products. Furthermore, most security applications (e.g., monitoring and auditing) do not consider those standards as the basis of their security check. Therefore, regardless of continuous efforts in publishing security standards, they are still under-utilized in practice. Such under-utilization might be caused by the fact that existing security standards are intended more for high-level recommendations than for being readily adopted to automated security applications on the system-level data. Bridging this gap between high-level recommendations and low-level system implementations becomes extremely difficult, as a fully automated solution might suffer from high inaccuracy, whereas a fully manual approach might require tedious efforts. Therefore, in this thesis, we aim for a more practical solution by proposing a partially automated approach, where it automates the tedious tasks (e.g., summarizing long standard documents, and extracting device specifications) and relies on manual efforts from security experts to avoid mistakes in finalizing security rules. We apply our solution to IoT by implementing it with IoT-specific standards (NISTIR 8228) and smart home networks. We further demonstrate the actionability of our derived rules in three major applications: security auditing, Intrusion Detection systems (IDS), and secure application development
Screening Dynamic Phenotypes for Synthetic Biology
Get PDFSynthetic Biology provides an avenue for reengineering the molecular machinery that make up cells. It has the potential of becoming a significant driver for discovery of new therapies and diagnostic methods. In fact, advances in molecular biology have made it easier to create large pools of edited cells, but there is a technological bottleneck to screen these cells to capture their phenotypes and link them to genotypes. Conventional screening technologies like well based structured arrays and Fluorescence-activated cell sorting (FACS) provide a means to screen genetically edited cells, but their current limitations prevent capturing dynamic phenotypes from mixed populations of edited cells. Microfluidic technologies provide alternatives that can be combined with timelapse microscopy to capture phenotypes. Paired with other techniques, these devices can provide ways to genotype mixed populations in situ and externally with single cell resolution. This work involves one of such techniques referred to as Single Cell Isolation Following Timelapse (SIFT), used to screen mixed libraries of synthetic oscillators. However, it is currently limited to Escherichia coli (E.coli) and further research is needed to adapt it to mammalian cells. As such, this thesis presents our implementation of the technique for screening reengineered E. coli cells in combination with an existing machine learning segmentation method referred to as Deep Learning Time-lapse Analysis (DeLTA). Similarly, this work features preliminary results to extend SIFT to Jurkat cells (human leukemic T cell line ). In brief, the presented work involves the implementation of a microfluidic set-up to screen mixed populations of edited cells
Boundedness of Operators on Local Hardy Spaces and Periodic Solutions of Stochastic Partial Differential Equations with Regime-Switching
Get PDFIn the first part of the thesis, we discuss the boundedness of inhomogeneous singular integral operators suitable for local Hardy spaces as well as their commutators. First, we consider the equivalence of different localizations of a given convolution operator by giving
minimal conditions on the localizing functions; in the case of the Riesz transforms this results in equivalent characterizations of . Then, we provide weaker integral conditions on the kernel of the operator and sufficient and necessary cancellation conditions to ensure the boundedness on local Hardy spaces for all values of p. Finally, we introduce a new class of atoms and use them to establish the boundedness of the commutators of inhomogeneous singular integral operators with bmo function.
In the second part of the thesis, we investigate periodic solutions of a class of stochastic partial differential equations driven by degenerate noises with regime-switching. First, we consider the existence and uniqueness of solutions to the equations. Then, we discuss the
existence and uniqueness of periodic measures for the equations. In particular, we establish the uniqueness of periodic measures by proving the strong Feller property and irreducibility of semigroups associated with the equations. Finally, we use the stochastic fractional porous
medium equation as an example to illustrate the main results
Corporate climate practices and uses of greenhouse gas reporting: conceptualizing responsibility, filling reporting gaps, and assessing strategic accounting
Get PDFThis dissertation investigates the meanings and practices of corporate climate responsibility (CCR), with a special focus on greenhouse gas (GHG) accounting. Insufficient climate regulation has given rise to many fragmented options for corporate climate action. This enables inconsistent and strategic uses of climate practices, consequently impinging on effective climate mitigation and understandings of corporate climate impacts. I address these issues within the three manuscripts of this dissertation. The first manuscript improves our understanding of CCR by identifying four frames in which CCR is conceptualized and determining whether each frame aligns with a social justice perspective on responsibility. The second manuscript addresses the gap in company-level emissions data resulting from incomplete GHG reporting. We train three machine learning models to predict company-level Scope 1 emissions and use the best model to estimate global emissions from public companies. The third manuscript investigates whether companies are strategically delineating their organizational boundaries according to different consolidation approaches when conducting GHG accounting. The first manuscript demonstrates that CCR is conceptualized according to scientific, social, legal, and economic frames. We find that the scientific frame is most aligned with a social justice perspective on responsibility, while the economic frame is least aligned. According to these insights, we provide recommendations for a new and comprehensive understanding of CCR. In the second manuscript, our best model shows an improvement in prediction accuracy compared to a benchmark study. We estimate that emissions from public companies are 22% (11.4 GtCO2e) of global GHG emissions in 2021. We also find that reporting companies make up 82% of global corporate emissions, implying that high emitters are already reporting their emissions. The third manuscript results suggest that companies are not using consolidation approaches strategically. However, companies are not transparent about why they choose certain consolidation approaches. Altogether, this research highlights the need for a common understanding and adoption of CCR and the climate practices which define it. In doing this, we help guide companies and policymakers to prioritize certain climate practices over others. While companies must continue to report their emissions and be more transparent about their accounting methodologies, there should be an increased focus on implementing carbon management systems that facilitate real decarbonization
Droplet-based microfluidics for screening and single-cell analysis
Get PDFThe field of biology and biochemistry relies heavily on efficient screening procedures to discover and develop new entities or optimize existing processes. However, traditional screening methods are time-consuming, labor-intensive, and expensive, requiring thousands to millions of experiments. Microfluidic and automation technologies offer a promising solution to this problem, enabling high-throughput screening (thousands of droplets in a few seconds) in a much faster and less expensive manner. In addition to accelerating the screening processes, microfluidic technologies can reduce reagent consumption and improve precision and control through automation and miniaturization of experimentation. However, droplet-in-channel microfluidic systems are limited in terms of fluidic operations as they manipulate droplets only by pressure-based flows. In contrast, digital microfluidics provides greater programmability by manipulating droplets using integrated electrodes. However, this precise control and manipulation significantly decreases the system throughput.
Therefore, this thesis aims to integrate droplet and digital microfluidic systems to offer valuable insights into the potential of microfluidic technologies for enhancing the efficiency of screening procedures in the field of single-cell analysis and biochemical synthesis. By integrating droplet and digital microfluidic systems, we propose new methods for single-cell studies, such as mammalian cells gene editing and monoclonal antibody discovery. Furthermore, the developed high throughput screening system can be used to screen large libraries of potential therapeutics and diagnostics, such as radiotracers for bioimaging applications. We also propose to leverage design-of-experiment methodologies and machine learning algorithms to enhance the efficiency of digital microfluidics for optimization of biochemical synthesis reactions. These works involve the development of new hardware and software, and integration of biological assays and biochemical reactions on these platforms. These systems can expand and improve the application of microfluidic and automation systems for biotechnology industries
BLE-based Indoor Localization and Contact Tracing Approaches
Get PDFInternet of Things (IoT) has penetrated different aspects of modern life with smart sensors being prevalent within our surrounding indoor environments. Furthermore, dependence on IoT-based Contact Tracing (CT) models has significantly increased mainly due to the COVID-19 pandemic. There is, therefore, an urgent quest to develop/design efficient, autonomous, trustworthy, and secure indoor CT solutions leveraging accurate indoor localization/tracking approaches. In this context, the first objective of this Ph.D. thesis is to enhance accuracy of Bluetooth Low Energy (BLE)-based indoor localization. BLE-based localization is typically performed based on the Received Signal Strength Indicator (RSSI). Extreme fluctuations of the RSSI occurring due to different factors such as multi-path effects and noise, however, prevent the BLE technology to be a reliable solution with acceptable accuracy for dynamic tracking/localization in indoor environments. In this regard, first, an IoT dataset is constructed based on multiple thoroughly separated indoor environments to incorporate the effects of various interferences faced in different spaces. The constructed dataset is then used to develop a Reinforcement Learning (RL)-based information fusion strategy to form a multiple-model implementation consisting of RSSI, Pedestrian dead reckoning (PDR), and Angle-of-Arrival (AoA)-based models. In the second part of the thesis, the focus is devoted to application of multi-agent Deep Neural Networks (DNN) models for indoor tracking. DNN-based approaches are, however, prone to overfitting and high sensitivity to parameter selection, which results in sample inefficiency. Moreover, data labelling is a time-consuming and costly procedure. To address these issues, we leverage Successor Representations (SR)-based techniques, which can learn the expected discounted future state occupancy, and the immediate reward of each state. A Deep Multi-Agent Successor Representation framework is proposed that can adapt quickly to the changes in a multi-agent environment faster than the Model-Free (MF) RL methods and with a lower computational cost compared to Model-Based (MB) RL algorithms. In the third part of the thesis, the developed indoor localization techniques are utilized to design a novel indoor CT solution, referred to as the Trustworthy Blockchain-enabled system for Indoor Contact Tracing (TB-ICT) framework. The TB-ICT is a fully distributed and innovative blockchain platform exploiting the proposed dynamic Proof of Work (dPoW) approach coupled with a Randomized Hash Window (W-Hash) and dynamic Proof of Credit (dPoC) mechanisms
Investigating Vortex Ring Reconnection in Twin Parallel Pulsed Jets: Influence of Nozzle Spacing and Stroke Ratio
Get PDFEven though interactions between pulsed jets showed great importance in biological fluid transport, they remain poorly described. An experimental piston/cylinder apparatus is designed to produce twin parallel pulsed jets. Using Particle Image Velocimetry (PIV), we investigate how vortex ring reconnection is influenced by nozzle spacings (S/D_0) varying from 1.49 and 3.20 and stroke ratios (L/D_0) between 2 and 4. Velocity and vorticity visualization suggest there is a critical spacing ratio from which the pulsed jets interact. This value is found to be approximately 3. Below 1.5, the vortex rings are already merged at the jet exit. By implementing a vortex core identification method based on the swirling strength criterion, the reconnection point is then localized. The results highlight how important is the effect of the nozzle spacing compared to the stroke ratio, although the influence of L/D_0 increases with the distance between the jets. Finally, time-frequency analyses confirm the highly fast changes in velocity and vorticity observed during reconnection, and emphasize the importance of the reconnection phase in the newly formed structure
“Wading Against a Tide”: Emotions, Ethics and the Interstitial Space of Community Service Provision for Criminalized Mothers.
Get PDFIn this dissertation, I examine how community-based service providers support criminalized women navigating motherhood, substance use and identity change. To date, researchers have focused on the experiences of incarcerated people, with lesser attention paid to post-release realities. A dearth of research focuses on community-based organizations and the service providers that work within them to support criminalized people.
Community service provision involves navigating the emotional dimensions of providers' work while supporting clients through emotionally charged experiences. Emotions are culturally and socially shaped experiences and are entangled in the precarity, structural and systemic conditions experienced by criminalized people. Service providers support their clients and witness emotions experienced by their clientele as they navigate child protection systems, substance use recovery and identity change processes. Simultaneously, service providers engage in emotion management while encountering the intimate details of their clients' lives and advocating for them against the realities and gaps of criminal legal, child protection, and welfare systems.
In this interstitial space of service provision, I ask how service providers engage in this emotion management strategies to support criminalized women. I examine the role of service providers in the context of structural and systemic gaps experienced by their clients. Through interviews with 23 community-based service providers working with criminalized women in Atlantic Canada and reflexive journaling, I argue that service providers engage in the emotional terrain of supporting their clients. I mobilize the concept of emotional-ethical dilemmas, which I argue form the backdrop of service providers’ work and highlight the constraints in their capacity related to organizational mandates, limited funding, and compassion fatigue.
Key findings underline the importance of trauma-informed and harm reduction practices and services as supports for criminalized women and to ease the emotional-ethical dilemmas experienced by service providers. The findings draw attention to the persistent complex unmet needs of criminalized women in Atlantic Canada, such as housing and poverty. I argue that community service providers largely fill gaps in how the state fails to attend to these needs. These unmet needs highlight how we respond to and support community-based service provision working to support criminalized women in the context of systemic and structural gaps, not individual failures
Genre in/of Crisis: Formal Mediations of the Anthropocene in Video Games and Digital Cinema
Get PDFThis thesis theorizes new, uncertain formations of genre in contemporary digital video games and cinema as an effective approach to mediating the feeling of life during the environmental and anthropocenic crises of the Anthropocene. Employing Gerald Voorhees’ Genre Trouble method of game studies alongside Selmin Kara’s theoretical framework of anthropocenema, this intervention proposes a means to understanding our anthropocenic anxieties through unique generic forms realized within contemporary digital video games and genre cinema. This thesis therefore asks, how has the Anthropocene imaginary impacted genre in contemporary digital media? And how, in turn, has genre been used to mediate the widespread feeling of living through the Anthropocene as we face the widely-recognized likelihood of eventual human extinction? Simply put, what is the generic form of anthropocenic crises? Establishing the ‘anthropogamic’ as a video game category analogous to anthropocenema, this thesis first examines the productive ecocritical potential of video games’ uncertain generic assemblage through the genre-bending extinction game Death Stranding. This thesis then follows the generic logics of the anthropogamic to examine similarly mutative relationships between digital technology and generic form in anthropocenema through the environmental science fiction/horror film Annihilation. Ultimately, this project posits the genre of crisis as genre in crisis to demonstrate how the Anthropocene has affected contemporary cultural production beyond explicit representations of crisis through uncertain and disorienting digital mutations of familiar generic categories. Additionally, through its interdisciplinary approach, this thesis aims to emphasize the productive scholarship that can occur in intersections between game studies and film studies
Standing In Between Two Mirrors: Queer Reflections in the Work of Geoffrey Farmer
Get PDFThis thesis offers a queer reading of the artistic practice of Canadian artist Geoffrey Farmer (b.1967) by situating queerness as the foundation for Farmer’s approach to artmaking. This thesis considers Farmer’s practice between 1992 and 2017, contextualizing the artist’s work within the shifting landscape of LGBTQ+ politics. This twenty-five-year frame contemplates the different realities for gay men, from the peak of the AIDS crisis to the legalization of same-sex marriage in North America. This thesis comprises of three chapters that examine the artist’s engagements with the future, past, and present. The author employs queer theory as a lens to consider Farmer’s vast practice as it provides a historical and theoretical framework that unfolds alongside the artist’s career. Various concepts from studies on queer temporalities are applied to make sense of the artist’s relation to time and better comprehend his depictions of it. Chapter 1 examines the artist’s emerging career in the 1990s and explores early works that depicted homosexual desire and advocated for gay identity. Early drawings, videos, and installations inspired by science fiction and popular culture are read here for aspects of queer futurity. Chapter 2 focuses on Farmer’s practice in the 2000s and analyzes his better-known installations that deconstruct and re-organize space and time. The author maps Farmer’s interests in archives and reads his disruptive acts as efforts of ‘queering’ the past. This research culminates with a critical reading of the artist’s installation, a way out of the mirror (2017), at the Canada pavilion for the fifty-seventh Venice Biennale. Chapter 3 examines how this prestige coincided with the country’s sesquicentennial anniversary, also known as ‘Canada 150.’ The author contemplates the artist’s personal narratives platformed on this national stage during this political moment through readings of homonationalism to unpack what was at stake in the present. Throughout the thesis, the author argues for the need and value of applying a queer perspective to Farmer’s work as it offers a nuanced understanding of the artist’s illustrious career