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The National Film Board of Canada and the Canadian Discourses of Immigration
Get PDFIn this paper, we examine the articulation of immigration discourse in the National Film Board of Canada (NFB) film productions. We also address the interdiscursivity of “racialized discourse” and “economic discourse” regarding immigration, as articulated in these films. Specifically, we use insights from Fairclough’s Critical Discourse Analysis to examine how documentary films by the National Film Board of Canada both construct and hide Canadian exceptionalism. We argue that exceptionalism constituted in NFB media discourse creates an “imaginary” of immigration as an altruistic and ethical practice. At the same time these discourses obscure the fact that Canada’s immigration discourse is largely driven by economic motivations. White Canadians are portrayed as good global citizens with virtues such as tolerance, neutrality, openness, inclusiveness, fairness, social justice, etc. On the other hand, only those immigrants who are willing to assimilate/integrate into the Canadian imaginary are included in the imaginary. We take a sample of three documentary films produced by NFB from 1949 to 1998 to have a longitudinal look at the propagation and perpetuation of exceptionalist discourses on immigration and to argue that notwithstanding the benevolence inherent in policy and academic discourses the prime motivation behind acceptance of immigrants has always been economic
Understanding Crack Formation in IN738 Alloy Fabricated by Laser Powder Bed Fusion and Heat Treatment Process
Get PDFCracking often occurs after Laser Powder Bed Fusion (LPBF) due to residual stresses from the manufacturing process. To mitigate these stresses, post-processing methods like stress relief Heat Treatment (HT) are used. This study combines computational and experimental methods to analyze and predict macro crack behavior in two geometries—dog bone and cruciform—fabricated from LPBF IN738 alloy. The objective is to understand and predict macro crack formation following LPBF and HT to prevent cracking. A coupled thermomechanical analysis was conducted to identify locations and timing of stress concentrations in the geometries. A simulation workflow was developed quantifying residual stresses at various stages of LPBF and HT. Fracture analysis using the stress intensity factor, a parameter in fracture mechanics, was performed to predict crack formation. Both numerical simulations and experimental validations were employed to assess this approach's effectiveness. Results showed that the stress intensity factor at stress concentration sites exceeded IN738's fracture toughness, indicating potential cracks. Despite geometric differences, both geometries showed similar stress peak patterns and crack behavior. High stress concentrations were observed early in the build process, during HT, and after cooling. The study also examined the impact of post-process sequences, such as HT and base plate removal, on geometric accuracy. These findings provide insights for designing geometries to prevent cracking and emphasize the role of geometric features and process sequencing in optimizing additive manufacturing. Understanding the relationship between design, residual stresses, and process sequences aids in developing robust design strategies and post-processing techniques to enhance LPBF component designs
Study of Roof-Mounted Vertical Axis Wind Turbines in Different Environments
No full textThe need for sustainable energy solutions is more pressing than ever, and wind energy presents a promising option. Among various wind turbine designs, the Vertical Axis Wind Turbine (VAWT) stands out due to its efficiency in low-wind conditions and its ability to capture wind from any direction. This study utilizes Computational Fluid Dynamics (CFD) to explore the potential benefits of installing VAWTs on roof-tops of buildings. By employing CFD simulations, we analyze the efficiency and performance improvements achievable through strategic placement of VAWTs in urban environments.
Placing VAWTs on building roof-tops is significant for harnessing local wind energy and reducing the costs and losses associated with power transmission. By integrating wind turbines directly into the building structure, energy can be generated on-site, thereby enhancing energy efficiency. Our findings indicate that a VAWT installed on a 30.48 m (100 ft) building roof-top can achieve up to a 36% increase in maximum power output, compared to the uniform flow. For taller buildings, this increase can reach up to 84%, demonstrating the substantial impact of building height on wind energy capture.
The study further investigates the placement of VAWTs at various positions on roof-tops and examines the effects of the Atmospheric Boundary Layer (ABL) on performance. Results reveal that the power coefficient (CP) of VAWTs can reach 0.487 in minimally obstructed coastal areas but decreases with increased terrain roughness. Additionally, positioning a VAWT on a dome structure, compared to a cubic building of equal height, results in a significant 50.7% increase in the maximum CP. This variation underscores the importance of building shape and placement in optimizing wind energy capture.
Establishing a human presence on Mars may be a possibility in the next few decades. In such a scenario, energy production is crucial. Domes are likely to be the preferred living structures on Mars, offering stability and protection against the planet harsh conditions. Positioning VAWTs atop these domes can effectively capture Martian winds, providing a sustainable and reliable energy source for the inhabitants. Winglets on the VAWTs improve aerodynamic efficiency by mitigating tip vortices, leading to a CP increase of up to 35.8% compared to uniform flow in the Martian atmosphere at optimal Tip Speed Ratios (TSRs). Furthermore, placing the VAWT on a dome enhances performance by accelerating incoming flow and reducing vortex formation, achieving a CP increase of 53.9% at peak performance, compared to uniform flow.
Placing VAWTs on roof-tops significantly boosts power extraction, with increases in energy output for taller buildings. The strategic positioning of VAWTs, particularly on domes and at various roof-top locations, proves essential for optimizing wind energy capture. The findings underscore the potential for VAWTs to enhance energy efficiency both in terrestrial and extraterrestrial environments, paving the way for more sustainable energy solutions
Urban Building Energy Models for District Cooling: A Data-Driven Approach Considering Building and Occupant Behavior Dynamics
Get PDFDistrict cooling offers an energy-efficient solution for hot urban regions where cooling demands are high. Accurate and rapid predictions of cooling requirements are vital during the planning phase to support informed decision-making. Surrogate models, which combine physics-based simulations with statistical or machine learning techniques, can harness the strengths of both methods, leading to more accurate building energy predictions at a low computational cost. In this study, a surrogate model, which combines machine learning with building physics-based archetypes, is employed to predict the cooling energy use intensities for high-rise buildings in a mixed-use district. The proposed surrogate models predict the impact of building design parameters, building operation characteristics, and occupant-related parameters on building energy performance. High-rise building models, representative of the district, are created using EnergyPlus software. The detailed cooling load profiles of these baseline models are simulated, analyzed, and validated against measured data and literature benchmarks. The resulting cooling loads are then aggregated at the district level, providing a physics-based method for urban-scale energy prediction. Parametric simulations are automated in RStudio using the developed archetypes by altering key parameters such as building envelope characteristics, geometry, and operational parameters, including occupant behavior. The resulting datasets are used to train machine learning models to approximate the outcomes of physics-based simulations. Additionally, the trained models are integrated into a user-friendly interface, enabling computationally efficient predictions of cooling requirements for each building in the district. The developed models show excellent performance, with R² values near 1 and RMSE below 0.17 kWh/m²/month on unseen data. This study demonstrates the potential of surrogate machine learning in predicting and optimizing building energy performance under different design, operation, and occupancy settings. It also provides insights into the impact of training dataset size on the accuracy of surrogate machine learning models
Numerical Investigation of Ultrasound-Triggered Microbubble Contrast Agent Dynamics
Get PDFBiomedical ultrasound is widely employed as an imaging modality for anatomical assessment and to provide information on blood flow characteristics. There is increasing interest in employing microbubble contrast agents for diagnostic and therapeutic ultrasound. Unlike MR and CT agents, ultrasound contrast agents are comparable in size to a red blood cell, providing a purely intravascular agent for clinical radiology. Microbubbles are currently clinically employed in echocardiography and liver applications, as well as pre-clinically, for the tumors' characterization and quantifying perfusion. Critical to the effectiveness of contrast agent microbubbles is an understanding of their nonlinear vibrations and scattering within the vasculature, specifically within the microvasculature where standard ultrasound flow estimation suffers from slow blood velocity and low red blood cell concentration.
Using mainly a finite element computational approach, this thesis aims to investigate the nonlinear physics of ultrasound-stimulated microbubbles within small capillaries to shed some light on the vibration dynamic and behavior of microbubble contrast agents. Over three chapters of results, this thesis analyses the complex vibration dynamics of microbubbles in proximity to each other and confined in a viscoelastic vessel. The results provided in this thesis explain how the resonance behavior of a microbubble is dampened and shifted by its neighboring bubbles and how smaller bubbles show off-resonance activities corresponding to the resonance behavior of the bigger, neighboring bubbles. The results also explain how initial phospholipid packing and bubble
proximity affect subharmonic response and how a viscoelastic vessel dampens resonance behavior and amplifies off-resonance behavior.
This thesis conducts a robust study on ultrasound-stimulated microbubble-compliant vessel interactions. It will contribute to optimal contrast agent design for both imaging and therapy, image quantification, and the development of new ultrasound pulse sequences
Enhancing Deep Learning Model Robustness: Insights from Out of Distribution Data Augmentation and an Innovative Image Compression Technique
Get PDFDeep learning models excel when tested on images within their training distribution. However, introducing minor perturbations like noise or blurring to the model’s input image and presenting it with out-of-distribution (OOD) data can significantly reduce accuracy, limiting real-world appli- cability. While data augmentation enhances model robustness against OOD data, there is a gap in comprehensive studies on augmentation types and their impact on OOD robustness.
A common belief suggests that augmenting datasets to bias models towards shape-based fea- tures improves OOD robustness for convolutional neural networks trained on ImageNet. However, our evaluation of 39 augmentations challenges this belief, showing that an augmentation-induced in- crease in shape bias does not necessarily correlate with higher OOD robustness. Analyzing results, we identify biases in ImageNet that can be mitigated through appropriate augmentation. Contrary to expectations, our evaluation reveals no inherent trade-off between in-domain accuracy and OOD robustness. Strategic augmentation choices can simultaneously enhance both.
Model performance is influenced not only by perturbations but also by the image compression format. Efficient algorithms for image compression play a crucial role in managing costs associ- ated with data storage. We propose an innovative region-based lossy image compression method named PatchSVD, leveraging the Singular Value Decomposition (SVD) algorithm. Experimental results demonstrate that PatchSVD surpasses SVD-based image compression across three common image compression metrics. Furthermore, we conduct a comparative analysis of compression arti- facts between PatchSVD, JPEG, and SVD-based compression, revealing scenarios where PatchSVD artifacts are preferable over both JPEG and SVD artifacts
Painting Punks and Pansies: Art as Affective Archive of Punk and Queer Subcultures in Postwar Kreuzberg
Get PDFThis thesis will analyze neo-expressionist paintings made in Kreuzberg during the late 1970s and 1980s. The analysis will include Helmut Middendorf’s “Electric Night” (1979), "Großstadt Eingeborene" (1979), “Big City Natives” (1980), and “The Singer” (1981), Rainer Fetting’s “Van Gogh und Mauer V” (1978), “Grosse Dusche” (1980), “Figur an der Mauer” (1987), Salomé’s “Self-portrait” (1981), “Verschärftes Aufsteigen” (1981), “Nackt in Gelb” (1981), Luciano Castelli’s “Olé” (1981), and their joint work “Rote Liebe” (1979), as well as Bernd Zimmer’s “Brennende Fabrik III” (1981), and “Verwandlung” (1983). Ultimately, I seek to demonstrate that these works offer insight into the obscured subcultural communities of postwar Kreuzberg.
My analysis of these artworks will draw on several methodologies, frameworks, and concepts. It will be heavily centered on affect theory, masculinity and queer theory, semiotics, fashion history, as well as the deep and complex entanglement of all of these notions. I will also draw from the anecdotal and oral histories provided to me by the artists themselves, artistic experts, and other individuals involved in Berlin’s postwar artistic and subcultural scenes. Through these many avenues, I will unpack and analyze the aforementioned artworks in order to demonstrate how they present distinctive transgressive aesthetics that can be read as an affective archive of Kreuzberg’s punk and queer subcultures of the late 1970s and 1980s
After and Before
No full textThe overarching motivation of After and Before centers on a deeply ingrained desire for a candid, authentic and occasionally humorous portrayal of queer identities—particularly within a Canadian context—and to explore themes and subjects that are, in the opinion of the writer, not readily addressed within the sphere of contemporary queer literature. These subjects include domestic and sexual violence, the construction of body image, the experience of aging as a queer individual, loneliness and grief, and the influence of heteronormative values within the LGBTQ+ community. The cross-generational approach to this collection seeks to highlight the abiding systemic prejudices aimed against queer individuals within a variety of narrative styles. Thus, an interconnected thematic arc exists between all the stories featured within this anthology. From the 1980s of “Salmon Son” to the bleak near-future of “Rhetoric,” After and Before highlights the all too frequently circular nature of oppression and otherization within our society
Facets of the Reborn Doll Phenomenon: Non-reproductive Motherhood, Synthetic Relationships, Performance, Community, and Self-care
No full textThis dissertation begins by addressing some basic questions about the hyper-realistic reborn dolls collected by thousands of women around the world, such as: How are reborns made? Who buys them? What are typical reactions to the dolls? And, beyond these initial questions, I consider the purpose and potential of these dolls as a hobby, and also as something more than a hobby. My second chapter delves into the culture surrounding not just reborn dolls but the whole concept of babies and reproduction in order to situate reborns in relation to motherhood. The connection between reborns and motherhood is not as straightforward as it may seem at first glance. Through the theoretical lens of the ‘good life’ (as described in Lauren Berlant’s Cruel Optimism) I will describe how reborns emerge from pronatalist rêverie but also subvert reproductive optimism by offering an alternative to heteronormative reproduction. From there, Chapter Three examines how reborn dolls (and also sex dolls) provide fulfilling synthetic relationships that produce real emotions. These relationships are therapeutic for many and there is evidence that thousands of people are engaging in synthetic relationships all around the world. I argue for the potential of synthetic relationships to provide outlets for the rehearsal of power significant in the production of self. This chapter will also address the sense of control, pleasure, and self-worth that comes from managing one’s personal collection. The final chapter investigates the therapeutic elements of reborn dolls. Evidence from the context of doll therapy in dementia care demonstrates the benefits of doll play. Membership in a doll enthusiast community provides a sense of belonging for this oftentimes alienating interest. Big questions about the future of synthetic relationships (with dolls and also with artificial intelligences) are prompted by this investigation of actual doll relationships happening today. Reborn dolls are queer, fantastical, beloved by collectors from a range of economic, political and cultural backgrounds, and they will always remain uncanny. Understanding these fascinating objects tells us about a niche hobby grounded in physical touch that is surging in popularity in the midst of the ever-ephemeral and intangible digital age
A Map of One’s Own: Cartographic Subversion in the Work of Shuvinai Ashoona, Firelei Báez, and Sandy Rodriguez
Get PDFA long-standing relationship between the map and visual art is continued today by a number of contemporary artists whose work uses a variety of cartographic concepts and strategies. This thesis focuses on three artists, Sandy Rodriguez, Firelei Báez, and Shuvinai Ashoona, who address and undermine the map as a technology of colonial power. Brought together for the first time here, these three artists accomplish a decolonial subversion of the map–as an object complicit in past and present processes of colonization. Drawing on the work of scholars from geography, Black studies, decolonial studies, and art history, this thesis addresses, in detail, how each artist’s work pushes back against the assumed authority of the map