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Development of a Hygrothermal Model Validation Methodology Using a Two-Storey Guarded Hot Box
No full textHygrothermal performance is an essential component of building performance, with heat, air, and moisture transport through the building envelope as a key element. Current modelling programs such as Delphin can be used to simulate hygrothermal performance of building envelopes but require physical data for validation, either from in-situ or controlled laboratory experiments. This allows for confidence in the use of hygrothermal models. This thesis used a two-storey guarded hot box (GHB) apparatus to develop a testing sequence that provided sufficient data for confidence in validation. Two lightweight vertical walls were tested in the GHB, each for 1200 hours. The model validation was completed using graphical and statistical analysis. After an initial validation, model adjustments were completed based on the sensitivity of various model parameters. The improved models resulted in excellent agreement between the experimental and modelled performance
A Collection of New Algorithms in Post-Quantum Cryptography
No full textIn this thesis, we introduce several new algorithms and concepts within the topic of post-quantum cryptography. The security of Hamming weight code-based cryptography is largely based on the effectiveness of information set decoding (ISD) attacks. We introduce a modification to Stern's algorithm that reduces average decryption time by approximately 14% for a code of length 1024, dimension 524 capable of correcting 50 errors. We accomplish this by adding 3 extra columns to the columns reduced to the identity matrix and performing extra row reductions that manipulate the matrix into a form that still allows Stern's algorithm to be run. We introduce a new problem that cryptosystems can be based on, which uses a permutation of vector components to obfuscate ciphertexts. This thesis further introduces a new type of cryptosystem that uses this idea of vector component permutation to obfuscate plaintexts. The system appears resistant to improvements to lattice reduction algorithms and has key sizes that are usable for practical applications. We give a variation of the LWE problem that allows the modulus to be obfuscated. We give a decryption algorithm based on this obfuscated basis LWE and apply it to standard LWE decryption. We show this application and all immediate derivations give no advantages with regard to decryption failure rates of LWE systems. Finally, we show a connection between Module-LWE and Integer Ring-LWE systems and describe an attack that somewhat connects the security of the two systems
On The Amenability Of Inverse Semigroup Actions
No full textThe search for an appropriate notion of amenability for inverse semigroups is an ongoing program in operator algebras. This thesis approaches this problem using inverse semigroup actions. We say that an inverse semigroup action is amenable if its action groupoid is amenable, and prove two results from the literature on amenable inverse semigroup actions: firstly, that all actions of an inverse semigroup are amenable whenever the universal action is amenable; and secondly, that the universal action of S is amenable whenever S admits an idempotent-pure partial homomorphism into an amenable group. We then show that all actions of graph and abelian inverse semigroups are amenable, and that the universal action of the free inverse semigroup on two generators is not amenable. We also introduce an action of an inverse semigroup on its Stone-Cech compactification, and produce an example of an inverse semigroup with weak containment and nonamenable universal action
Mixed Fractional Sturm-Liouville Problems
No full textThis doctoral dissertation comprises two peer-reviewed papers and one paper that has been submitted for publication. The first paper has appeared in a peer-reviewed journal, while the second paper is published in an open access journal. The third paper has just been submitted. These three papers comprise chapters 2-4 herein. These articles address issues stemming from the investigation of fractional Sturm-Liouville problems under ordinary and fractional boundary conditions. In the first paper (Chapter 2), we present the general solution of three such two-term fractional equations of mixed Caputo/Riemann-Liouville type and then, in the corresponding eigenvalue problem, we find two-sided estimates as to their location as well as their asymptotic behavior as a function of the fractional order. In the second paper (Chapter 3), we investigate a non-self-adjoint fractional Sturm-Liouville problem with left Caputo and right Riemann-Liouville fractional integrals with Dirichlet boundary conditions. Our study reveals the existence of a finite set of real eigenvalues for certain where , and no real eigenvalues for near 1/2. As approaches 1 (i.e., the classical Sturm-Liouville case), the number of real eigenvalues approaches infinity, and so the spectrum resembles that of a standard Dirichlet problem. In the third paper (Chapter 4), we convert a fractional Sturm-Liouville equation, with fractional boundary conditions, to a hybrid fractional equation with classical boundary conditions and then prove that the eigenvalues of this problem are real and their eigenfunctions have an orthogonality property. We then prove a result analogous to Sturm's comparison theorem and state a number of results and conjectures regarding the zeros of solutions of such problems. We end by showing that, depending on the definition of the fractional operators, transformations of dependent variables can greatly simplify the presentation and resolution of the problems and conjectures we stated
Performance Evaluation of HTTP/2 and HTTP/3(QUIC) using Lighthouse
No full textThis thesis embarks on a comparative analysis of HTTP/2 and HTTP/3 protocols across two prominent web servers, Nginx and OpenLiteSpeed, under various network conditions spanning baseline performance, impact of delay, impact of packet loss, and throughput scenarios employing Google Lighthouse metrics to assess web performance indicators like FCP, SI, LCP, CLS, Performance Score, and Throughput. The findings reveal that, under no-delay conditions, both Nginx and OpenLiteSpeed exhibit high performance with marginal distinctions between the two protocols. Notably, HTTP/3 consistently surpasses HTTP/2 across all metrics except for Throughput where HTTP/2 gained little advantage. The result reveals HTTP/3's superior capability to manage network instabilities and packet loss. Furthermore, OpenLiteSpeed demonstrates a slight advantage over Nginx, particularly when leveraging HTTP/3, suggesting an optimization that subtly favors its architecture. This study emphasizes the critical role of selecting the appropriate server and protocol to optimize web performance, particularly under challenging network conditions
On The Topological Center Problem For Certain Banach Algebras From Abstract Harmonic Analysis
No full textThis thesis discusses Banach algebras arising from abstract harmonic analysis and the topological center problems related to them. Let G be a locally compact group. We start with determining the topological center of . We present two general Banach algebra approaches to tackle this problem. The first approach shows the strong Arens irregularity of the algebra when G is compact. The second approach shows that the same conclusion still holds when G is non-compact. Indeed, the first approach shows that any weakly sequentially complete Banach algebra that has a bounded approximate identity and is a two-sided ideal in its bidual is strongly Arens irregular; the second approach determines, more generally, the topological centers of the Beurling algebras and , with a mild assumption on the weight function . Lastly, the second approach shows the strong Arens irregularity of for some specific groups
The splicing inhibitor isoginkgetin induces transcription of metallothionein genes through the metal responsive transcription factor MTF-1
No full textPre-mRNA splicing is a critical step in the formation of mature mRNAs and when dysregulated, can contribute to the development/progression of many diseases. Isoginkgetin (IGG) is a natural bioflavonoid abundant in Ginkgo biloba extracts used in traditional Chinese medicine for its anti-inflammatory properties. IGG also inhibits pre-mRNA splicing and exhibits anti-neoplastic activity. Previous work in our lab indicated that IGG exposure leads to increased expression of metal-related transcripts involved in the response to metal ions. In response to heavy metals, these transcripts are regulated by the metal regulatory transcription factor 1 (MTF-1). Here, IGG led to increased proportions of MTF-1 in the nucleus and increased expression of these transcripts. siRNA-mediated knockdown of MTF-1 resulted in significant reductions in basal and IGG-induced expression of these metal-related transcripts. The present work supports a role for MTF-1 in the IGG response with possible implications for anti-neoplastic activity of IGG and/or related anti-neoplastic agents
Sonic Constructions of Transhumanism: A Radiohead Case Study
No full textThis thesis explores connections between voice and body through the lens of transhumanism. The voice exists as a sound constructed by the body and a medium for constituting body. This reciprocal relationship gives rise to an ongoing process of transformation. Together with literature on materiality of sound and listening, vocality, and phenomenology, I develop a conceptual framework rooted in transhumanism to: (1) examine how musical and sonic practices mediate understandings of the human body, and; (2) consider dialectical tensions between biological and technological bodies. I apply this to a case study on Radiohead, tracing their aesthetic shift across three albums: The Bends (1995), OK Computer (1997), and Kid A (2000). In understanding voice as the foregrounded sonic layer through which Radiohead navigate their humanness, I discuss how vocalic changes, both in techniques and interactions with other sonic elements, allow Radiohead to negotiate identity and agency, and to undergo transhumanistic reconstruction
Putting Words to Actions: International Discourse, Narrative, and Language During the Bosnian War, 1992-1995
No full textThis project is a look at how history was written in public facing documents during the Bosnian War between 1992 and 1995. I identify and analyze three basic discourses used by three agencies who managed the international response to the war: the United Nations Security Council, the International Committee of the Red Cross, and the United Nations High Commissioner for Refugees. To frame narratives of events of the war and the problems they were facing, the public communications of these agencies used three general discourses that I label humanitarianism, ethnic cleansing, and hyphenated identities. Each discourse was used by all three agencies and highlighted a different set of problems facing the international organizations and signaled the organizations’ priorities for intervention and peace. The discourses variously constructed political parties and armed actors, civilians, prisoners and detainees, women, displaced people and refugees, and UN and humanitarian personnel to create narratives and present the conflict to their publics. These documents were written primarily for journalists, donors, and governments who then communicated the events of the war to a wider audience. Methodologically, this dissertation argues that it is possible to use discourse analysis to track changes in international policies and priorities through a close examination of the language that is used to describe people and events. The ultimate contribution of this project is that it calls attention to which groups are included and excluded in international discourses of war and posits that defining groupness is a key element in how international intervention to armed conflict is conceived
Ghrelin Regulates Food Intake in the Ventral Tegmental Area During Chronic Psychosocial Stress
No full textGhrelin is a stomach derived hormone that promotes food intake through binding to the growth hormone secretatogue receptor (GHSR). The GHSR is expressed throughout the brain, including in the hypothalamus where it responds homeostatic signals and throughout the reward system where it modulates food seeking behavior. Notably, ghrelin is also involved in the regulation of feeding behaviors in the face of chronic stress, as prolonged stress exposure induces a metabolic challenge, to which ghrelin promotes caloric intake to sustain increased energetic demands. One GHSR-expressing region that has also been implicated in the stress response is the ventral tegmental area (VTA), a principal component of the reward system. Previous research illustrates that the GHSR plays a critical role in regulating the metabolic and behavioral outcomes associated with chronic stress, little is known about how GHSR activity in the VTA contributes to such outcomes. The aim of this thesis was to investigate how the ghrelin system within the VTA modulates feeding behavior in response to chronic social defeat stress in mice. Additionally, we sought to determine how ghrelin regulates these aspects of the stress response in female mice, as they have largely been excluded from neuroendocrine research. The data described in the following thesis illustrate that chronic social defeat stress induces changes to the neurovasculature unit that results in an increase in ghrelin movement and activation within the VTA, ultimately leading to increased food intake. Within the VTA ghrelin regulates metabolic outcomes through signaling of the GHSR, as we demonstrate that, within this region, the GHSR is required to promote food intake. Female mice exposed to an adapted social defeat paradigm display similarities in ghrelin secretion, food intake but highlight differences in GHSR expression, compared to males and previous findings. In sum, the results presented in this thesis provide evidence that chronic stressors alter sensitivity to ghrelin, an effect that is mediated through the GHSR within the VTA, ultimately leading to increased caloric intake