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The impacts of climate change on traditional brick masonry construction: A case study of The Sheesh Mahal Complex, Lahore Fort, Pakistan
Get PDFPakistan is among the 10 countries that will be most affected by climate change. While the country contributes less than 1 percent of the world\u27s greenhouse gases responsible for causing global warming, its 200 million people are among the world\u27s most vulnerable victims of the growing consequences of climate change. The nation is facing ever-rising temperatures, drought, and flooding that present serious threats to the country’s rich built heritage. This research explores the traditional passive climate-control strategies that have been used in Pakistan’s traditional brick masonry buildings to mitigate its hot arid climate and considers how these design solutions can be preserved and adapted in the rehabilitation of these historic masonry structures. The research further investigates the capacity and resiliency of these age-old strategies to perform under changing climate conditions and recommends methods to improve their performance. The Sheesh Mahal Complex in Lahore Fort provides an excellent case study to analyze this traditional regional form of passive cooling and the impacts of climate change on its performance efficacy. The Complex was built as a royal residence during the Mughal Period in the 16th century and incorporates hydraulic engineering, architectural design, and urban planning all together as an integrated whole. The research further examines how its current restoration can incorporate the existing passive environmental systems as part of a more sustainable conservation and management plan
Essays On Individual Health Insurance Market: Adverse Selection, Subsidy Design And Provision
Get PDFSubsidies are important policy tools against market failure in public health insurance programs. With the presence of adverse selection, subsidies of various forms encourage insurance purchase by low-risk consumers and promote insurance coverage towards the socially optimal level. In the context of the U.S. individual health insurance market, however, little evidence quantifies the degree of adverse selection. Neither is there evidence about how consumers value the subsidies, nor the overall welfare impact of subsidy provisions. This dissertation studies the social welfare implications of subsidy provision in the individual insurance market. I first quantify the degree of intensive margin adverse selection presented in the Affordable Care Act (ACA) Health Insurance Marketplaces (the exchanges). Using a novel dataset from a major U.S. insurer, I compare care utilization by individual market enrollees with respect to coverage level with enrollees in the commercial small group market. The coverage provision and consumer health status in the latter are the most comparable to those in the individual market, and coverage choices are plausibly exogenous. I present evidence of intensive adverse selection in the exchanges. I then study the design and empirical implication of price-linked subsidies. I develop a theoretical model to illustrate how the pass-through from cost shocks to subsidy payments depends on adverse selection and competition. Then combining individual-level enrollment data from the California exchange with the novel claims data, I quantify the pass-through in the exchanges. Lastly, I estimate the value of providing the Cost-Sharing Reduction subsidy—a subsidy that increases cover-age benefits—and compare the welfare consequences of this subsidy’s alternative financing strategies. I find that removing the Cost-Sharing Reduction subsidy will discourage enrollees in the lowest five percentile of health risk from obtaining insurance in the individual insurance market; consequently, premiums will increase by 5%-10%. Financing of the Cost-Sharing Reduction affects insurers’ incentive to participate in the market and, hence, total social surplus. Providing Cost-Sharing Reduction under the federal budget generates the highest total social surplus and achieves the highest return on public spending
Module 10: Youth Activism in Global Perspective (2010)
Get PDFhttps://repository.upenn.edu/teachingbeyondsept11-solidarity-justice/1001/thumbnail.jp
Module 15: Muslim Youth and Resistance (2015)
Get PDFhttps://repository.upenn.edu/teachingbeyondsept11-opinion-perception-sentiment/1001/thumbnail.jp
The ONESTOPers Guide to Well-Being
Get PDFThe Penn ONESTOP Service Center at the University of Pennsylvania is facing numerous challenges related to the COVID-19 pandemic, workplace environment changes, workload increase, role reclassification, personal pandemic-related challenges, and racial injustice. Penn ONESTOP seeks to increase resilience. Informed by current positive psychological literature, we propose three interventions to help Penn ONESTOP systematically develop character strengths awareness and literacy, develop a set of cultural core values to guide and unify workplace behavior, and build resilience. We recommend activities including character strengths conversations, strengths-spotting and recognition, a cultural core values workshop with positive introductions, and a series of resilience micro-lessons to put into practice. We suggest quantitatively measuring results with a culture & climate and engagement survey. Building a foundation of character strengths and shared core values will enhance and support improving resilience in Penn ONESTOP staff, setting them on the path to flourishing
Verisig 2.0: Verification of Neural Network Controllers Using Taylor Model Preconditioning
Get PDFThis paper presents Verisig 2.0, a verification tool for closed-loop systems with neural network (NN) controllers. We focus on NNs with tanh/sigmoid activations and develop a Taylor-model-based reachability algorithm through Taylor model preconditioning and shrink wrapping. Furthermore, we provide a parallelized implementation that allows Verisig 2.0 to efficiently handle larger NNs than existing tools can. We provide an extensive evaluation over 10 benchmarks and compare Verisig 2.0 against three state-of-the-art verification tools. We show that Verisig 2.0 is both more accurate and faster, achieving speed-ups of up to 21x and 268x against different tools, respectively
A New Look at “Didacus” in a Late Twelfth-Century Manuscript from Santa María de Benevívere (Free Library of Philadelphia, Lewis E 22)
Get PDFThe manuscript Lewis E 22 at the Free Library of Philadelphia has an uncommonly complete provenance. Written in the late twelfth century at Santa María de Benevívere in the Tierra de Campos of Palencia, Spain, an ex libris inscription on the last lines of the final folio records its origin, with an enigmatic addition by a later hand with the name “Didacus.” Following the exclaustration of Benevívere in the nineteenth century, the manuscript passed through a series of collections in England and Canada before it arrived in the United States with John Frederick Lewis, including those of William Braggeand George Dunn. Furnishing new evidence for its provenance and contextualizing its creation at Benevívere, this paper offers a new interpretation of the Didacus inscription as a memorial to the monastery’s founder, Diego Martínez de Villamayor (d. 5 November 1176)
Stress Shift Accompanying Verb Suffixation in Gujarati
Get PDFGujarati, an Indo-Aryan language primarily spoken in the state of Gujarat in northwest India, is a synthetic agglutinative language. Examining its systematic and extensive suffixation system provides an opportunity to shed more light on Gujarati stress by allowing observation of how stress shifts during suffixation. This paper investigates stress shift and corresponding root alternations accompanying suffixation in Gujarati Type 1 causatives and passives. It is shown that in these causatives and passives, Gujarati maintains a well-defined stress pattern, i.e. the ultimate syllable in di-syllabic words and the penultimate syllable in tri-syllabic words, by shifting the stress to the suffix
Improving Neural Network Robustness via Persistency of Excitation
Get PDFImproving adversarial robustness of neural networks remains a major challenge. Fundamentally, training a neural network via gradient descent is a parameter estimation problem. In adaptive control, maintaining persistency of excitation (PoE) is integral to ensuring convergence of parameter estimates in dynamical systems to their true values. We show that parameter estimation with gradient descent can be modeled as a sampling of an adaptive linear time-varying continuous system. Leveraging this model, and with inspiration from Model-Reference Adaptive Control (MRAC), we prove a sufficient condition to constrain gradient descent updates to reference persistently excited trajectories converging to the true parameters. The sufficient condition is achieved when the learning rate is less than the inverse of the Lipschitz constant of the gradient of loss function. We provide an efficient technique for estimating the corresponding Lipschitz constant in practice using extreme value theory. Our experimental results in both standard and adversarial training illustrate that networks trained with the PoE-motivated learning rate schedule have similar clean accuracy but are significantly more robust to adversarial attacks than models trained using current state-of-the-art heuristics
Balancing the (Horn) Scale: Explaining the Production-Comprehension Asymmetry for Scalar Implicatures
Get PDFPreschoolers struggle with Scalar Implicature (SI) generation, showing difficulties in interpreting the scalar element “some” with its upper-bounded meaning “some but not all”. Strikingly, despite the fact that the comprehension of “some” is not adult-like until at least 5 years of age, recent corpus data suggest that children, in production, can use “some” as “not all” already in their third year of life. In this paper, we propose the Asymmetry Account, an account of SI generation formulated in the framework of Bidirectional Optimality Theory (Bi-OT). By taking Bi-OT as a model of language use, we show that the comprehension of “some” requires hearers’ to consider the speaker’s perspective, but not vice versa: to produce “some” with its upper-bounded meaning no mentalizing about other perspectives is needed. In light of this, we predict that the comprehension of weak scalar elements such as “some” is cognitively more demanding than their production and argue that children’s difficulty with the “some”-implicature is to be related to children’s developing of cognitive abilities, in particular, Theory of Mind