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2023 research outputs found
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10. Queering Public Spaces: Spoken Word Performances as Acts of Resistance, Hope, and Community-Building
No full textAsymmetric Effects of Inflation on Income Inequality: Evidence from Threshold Models in Turkiye
No full textThe main objective of this study is to analyze the asymmetric effects of highly volatile inflation on income inequality in Türkiye between 1990 and 2023. Despite its high growth potential, Türkiye has a fragile economic structure and experienced a period of highly volatile inflation during the specified period. Such volatility may lead to imbalances in income distribution. Empirical studies specifically focusing on the asymmetric effects of inflation on income inequality in Türkiye remain limited. This study seeks to address this gap in the literature. Threshold regression and threshold Structural Vector Autoregression (SVAR) models are employed as suitable methodologies to investigate the relationship between inflation and income inequality. The Bai-Perron (1998) method is employed to determine threshold values, enabling inflation rates to be classified as either low or high, based on the period within the study\u27s scope. The findings reveal a U-shaped relationship between inflation and income inequality, indicating that while low inflation reduces inequality, high and unstable inflation increases it. The study also examines the effects of human capital and economic growth by utilising various additional variables. It provides general implications and recommendations based on the findings
Assessing the impact of binder saturation on print quality of binder jetted green samples of regular morphologies
No full textA pivotal process parameter in binder jetting additive manufacturing (BJAM) is binder saturation, defined as the volumetric ratio of binder deposited to voids within the powder bed. Improperly tailored binder saturation may lead to printing issues such as binder overspread, increased surface roughness, and layer delamination. These existing issues may be further exacerbated with the use of irregular morphological powders, which have a higher degree of interparticle friction and therefore tend to form powder beds with larger pores. This then slows down binder imbibition into the bed. This research will examine the effect of varying binder saturation on a regular (sphericity of 0.95) powder morphology and the resulting green part qualities using C18150 copper alloy powder. A metric used to assess quality is dimensional fidelity, evaluated using image processing techniques to compare designed vs. actual feature size of key geometric structures such as fine through holes and horizontal slots. Additionally, the green density of prints was evaluated with a precision balance and calipers on cubic samples. It was found that, for regular morphology powders, dimensional error did not scale with decreasing feature size. Thus, uniform compensation factors may be implemented into future CAD designs to improve dimensional accuracy
Vacancy fluctuations in a macroeconomic model with a strategic labor input target
No full textThis study investigates the effects of changes in job-filling and job-separation rates on economic fluctuations using an efficiency wage model. It introduces a relationship between labor input and the strategic labor input target into the model. This framework enables us to analyze situations in which vacancies exist along with employment and unemployment. The response of vacancy to a temporary positive productivity shock is amplified when fewer vacancies are filled and/or more turnovers take place. The simulations indicate that substantial changes in vacancy in response to the positive shock do not necessarily lead to significant employment changes, but depend on the job-filling and job-separation rates. This finding highlights the need to examine not only the change in vacancy but also filling vacancies and turnovers when discussing economic policies
SynPrivacy: An Open Framework and Fair Metric for Evaluating Synthetic Data Privacy Risks
No full textThe use of synthetic data in health applications raises privacy concerns, yet the lack of open frameworks for privacy evaluations has slowed its adoption. A major challenge is the absence of accessible benchmark datasets for evaluating privacy risks, due to difficulties in acquiring sensitive data. To address this, we introduce \synp, an open framework for benchmarking privacy in synthetic data generation (SDG) using simulated sensitive data, ensuring that original data remains confidential. We also highlight the need for privacy metrics that fairly account for the probabilistic nature of machine learning models. As a demonstration, we use \synp to benchmark CTGAN and propose a new identity disclosure risk metric that offers a more accurate estimation of privacy risks compared to existing approaches. Our work provides a critical tool for improving the transparency and reliability of privacy evaluations, enabling safer use of synthetic data in health-related applications
Perceiver Model Ensemble for Solar Power Forecasting: A Winning Solution for ClimateHack.AI 2023-2024
No full textIn this paper, we present Team Waterloo\u27s winning approach for solar power forecasting in ClimateHack.AI 2023-2024, an international machine learning competition. Our model leverages Numerical Weather Prediction (NWP), high-resolution visible (HRV) satellite imagery, and solar panel site metadata to predict photovoltaic (PV) power output over a 4-hour window. Our solution was an ensemble of Perceiver models that used spatial semantic pointers for spatial-temporal encoding, dynamic cropping, and efficient data handling. Our model can provide low-latency, high-accuracy forecasts and achieved a mean absolute error of 0.081 on the competition test set
Ex Tenebris: Black Fugitivity, Archival Whitewashing, and the (Re)imagination of Andromeda
No full textWhat happened to Black Andromeda? Why did Renaissance and post-Renaissance artists consistently portray Andromeda as a white woman despite Greco-Roman textual sources affirming her Ethiopian heritage? In what ways does reclaiming Andromeda’s Black roots incite contemporary conversations about representation and racial justice in art, iconography, and literature?
Drawing from Frantz Fanon’s postcolonial psychoanalytical theories in Black Skin, White Masks (1952), this paper interrogates the erasure of Andromeda’s Ethiopian identity in Western visual and literary traditions, tracing the transformation of a mythological Black princess into an archetype of European whiteness. From mapping the disregarded classical myths of Andromeda “from darkest Ethiopia,” as posited by mythographers such as Ovid, Strabo, and Pliny the Elder, the paper emphasizes how Andromeda’s African heritage was systematically erased and reduced to a "fugitive" element in both historical and contemporary artistic representations. By interrogating how Western archives, museums, and galleries perpetuate historical amnesia and racist ideologies by erasing non-white presences, it becomes imperative to challenge the ways in which gendered and racialized bodies may be marginalized, visually silenced, or rendered invisible altogether. Although this process gives rise to (pre-)modern modes of ethnic cleansing and erasure, equally important are the acts of resistance that emerge in the reception of such art and whitening phenomena. Accompanying the analysis is an original portrait drawn by L. Usanova that reimagines, re-edits, and reclaims Andromeda’s racial background according to her original mythos and literary-historical narrative. While the artwork aims to ‘do the practical work’ of uncovering the ‘white mask’ and participating in feminist (re-)editing praxes, the piece also serves as a direct intervention against Andromeda’s racial and aesthetic erasure by visually claiming a past, present, and future that asserts otherwise
Developing strategies for medium volume production in directed energy deposition additive manufacturing
No full textAdditive Manufacturing (AM) processes enable the validation of design variants, and the manufacturing of low volume specialty components. Slow fabrication times are an issue for larger production volumes, but for the directed energy deposition (DED) and hybrid manufacturing (where additive and machining operations are interwoven), new process planning scenarios can be explored for both low and medium volume production levels, which aligns well with addressing on-demand service and out of production components. DED AM is a material deposition based process. Wire filament or powder is melted by a heat source, and multi-axis tool paths can be employed to deposit the material. Large freeform components can be fabricated without support material; however, production volume scalability is an issue. Prior to exploring multi-function or reconfigurable machines and dynamic layouts, a framework for defining nomenclature for DED AM precedence diagrams and value stream maps, and insights for systematically decomposing components for macro and micro level process planning needs to be developed. The goal of this research is to provide a foundation for DED and hybrid manufacturing for low volume production (100 – 2000 pcs) for short planning horizons (1 week to 1 month) which would align to ‘medium volume’ production levels. This specific paper will present research performed to date on addressing these challenges
Data-driven approach for predicting abnormal grain growth in sintered binder jet steels
No full textAustenitic 316 stainless steel printed by binder jetting requires sintering to high densities to minimize porosity and have the corrosion resistance and strength required for most applications. While sintering can achieve densities above 99%, this paper reports the occurrence of abnormal grain growth (AGG) in this high-density region. A comprehensive process map is proposed, integrating key parameters to predict and inform grain sizes using regression model and machine learning approaches. Additionally, a clear relationship is identified between surface roughness, density, and grain size, offering a potential strategy for quality monitoring in serial production