28 research outputs found

    A Reissner-Mindlin plate formulation using symmetric Hu-Zhang elements via polytopal transformations

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    In this work we develop new finite element discretisations of the shear-deformable Reissner--Mindlin plate problem based on the Hellinger-Reissner principle of symmetric stresses. Specifically, we use conforming Hu-Zhang elements to discretise the bending moments in the space of symmetric square integrable fields with a square integrable divergence MHZHsym(Div)\boldsymbol{M} \in \mathcal{HZ} \subset H^{\mathrm{sym}}(\mathrm{Div}). The latter results in highly accurate approximations of the bending moments M\boldsymbol{M} and in the rotation field being in the discontinuous Lebesgue space ϕ[L]2\boldsymbol{\phi} \in [L]^2, such that the Kirchhoff-Love constraint can be satisfied for t0t \to 0. In order to preserve optimal convergence rates across all variables for the case t0t \to 0, we present an extension of the formulation using Raviart-Thomas elements for the shear stress qRTH(div)\mathbf{q} \in \mathcal{RT} \subset H(\mathrm{div}). We prove existence and uniqueness in the continuous setting and rely on exact complexes for inheritance of well-posedness in the discrete setting. This work introduces an efficient construction of the Hu-Zhang base functions on the reference element via the polytopal template methodology and Legendre polynomials, making it applicable to hp-FEM. The base functions on the reference element are then mapped to the physical element using novel polytopal transformations, which are suitable also for curved geometries. The robustness of the formulations and the construction of the Hu-Zhang element are tested for shear-locking, curved geometries and an L-shaped domain with a singularity in the bending moments M\boldsymbol{M}. Further, we compare the performance of the novel formulations with the primal-, MITC- and recently introduced TDNNS methods.Comment: Additional implementation material in: https://github.com/Askys/NGSolve_HuZhang_Elemen

    Toward a Critical Toponymy Framework for Named Entity Recognition: A Case Study of Airbnb in New York City

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    Critical toponymy examines the dynamics of power, capital, and resistance through place names and the sites to which they refer. Studies here have traditionally focused on the semantic content of toponyms and the top-down institutional processes that produce them. However, they have generally ignored the ways in which toponyms are used by ordinary people in everyday discourse, as well as the other strategies of geospatial description that accompany and contextualize toponymic reference. Here, we develop computational methods to measure how cultural and economic capital shape the ways in which people refer to places, through a novel annotated dataset of 47,440 New York City Airbnb listings from the 2010s. Building on this dataset, we introduce a new named entity recognition (NER) model able to identify important discourse categories integral to the characterization of place. Our findings point toward new directions for critical toponymy and to a range of previously understudied linguistic signals relevant to research on neighborhood status, housing and tourism markets, and gentrification.Comment: Accepted at EMNLP 2023 (main track

    A Reissner-Mindlin plate formulation using symmetric Hu-Zhang elements via polytopal transformations

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    In this work we develop new finite element discretisations of the shear-deformable Reissner--Mindlin plate problem based on the Hellinger-Reissner principle of symmetric stresses. Specifically, we use conforming Hu-Zhang elements to discretise the bending moments in the space of symmetric square integrable fields with a square integrable divergence. The latter results in highly accurate approximations of the bending moments M and in the rotation field being in the discontinuous Lebesgue space , such that the Kirchhoff-Love constraint can be satisfied for t tending to zero. In order to preserve optimal convergence rates across all variables for the case t tending to zero, we present an extension of the formulation using Raviart-Thomas elements for the shear stress. We prove existence and uniqueness in the continuous setting and rely on exact complexes for inheritance of well-posedness in the discrete setting. This work introduces an efficient construction of the Hu-Zhang base functions on the reference element via the polytopal template methodology and Legendre polynomials, making it applicable to hp-FEM. The base functions on the reference element are then mapped to the physical element using novel polytopal transformations, which are suitable also for curved geometries. The robustness of the formulations and the construction of the Hu-Zhang element are tested for shear-locking, curved geometries and an L-shaped domain with a singularity in the bending moments. Further, we compare the performance of the novel formulations with the primal-, MITC- and recently introduced TDNNS methods.Pre-prin

    Eine schubversteifungsfreie Formulierung der Reissner Mindlin Platte anhand Hu-Zhang Elemente

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    editorial reviewedEine neuartige Diskretisierung der Reissner-Mindlin-Plat- tengleichung, die für den symmetrischen Momententensor Hu-Zhang-Elemente und für die Schubspannungen Raviart-Thomas-Elemente einsetzt, wird vorge- stellt. Die Konstruktion des Hu-Zhang-Elements und entsprechende Transfor- mationsvorschriften werden diskutiert. Existenz und Eindeutigkeit werden be- wiesen und die Robustheit anhand von Beispielen demonstriert

    Evaluation of Total Daily Dose and Glycemic Control for Patients Taking U-500 Regular Insulin Admitted to the Hospital

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    OBJECTIVE: Patients using U-500 regular insulin are severely insulin resistant, requiring high doses of insulin. It has been observed that a patient\u27s insulin requirements may dramatically decrease during hospitalization. This study sought to systematically investigate this phenomenon. METHODS: We performed a retrospective chart review of patients with U-500 insulin outpatient regimens who were admitted to the San Antonio Military Medical Center over a 5-year period. Each patient\u27s outpatient total daily dose (TDD) of insulin was compared to the average inpatient TDD. The outpatient estimated average glucose (eAG) was calculated from the glycated hemoglobin (HbA1c) and compared to the average inpatient glucose. RESULTS: There were 27 patients with a total of 62 separate admissions. The average age was 64.4 years, with a mean body mass index of 38.9 kg/m CONCLUSION: U-500 insulin is prone to errors in the hospital setting, so conversion to U-100 insulin is a preferred option. Despite a significant reduction in insulin TDD, these patients had clinically similar glucose levels. Therefore, patients taking U-500 insulin as an outpatient can be converted to a U-100 basal-bolus regimen with at least a 50% reduction of their outpatient TDD. ABBREVIATIONS: BG = blood glucose eAG = estimated average glucose HbA1c = glycated hemoglobin NPO = nil per os SPSS = Statistical Package for the Social Sciences TDD = total daily dose

    Leadership Training in Endocrinology Fellowship? A Survey of Program Directors and Recent Graduates

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    Context: There is growing recognition that more physician leaders are needed to navigate the next era of medicine. Objective: To determine current opinions about leadership training in endocrinology fellowship programs. Design/Participants: Twenty-seven-question survey addressing various aspects of leadership training to current nationwide fellowship program directors (PDs) and fellowship graduates since 2010. Intervention: In partnership with the Endocrine Society, the electronic survey was advertised primarily via direct e-mail. It was open from March through July 2016. Main Outcome Measures: The survey addressed leadership traits, importance of leadership training, preferred timing, and content of leadership training. Results: Forty-six of 138 PDs (33.3%) and 147 of 1769 graduates (8.3%) completed the survey. Among PDs and graduates, there was strong agreement (\u3e95%) about important leadership characteristics, including job knowledge, character traits, team-builder focus, and professional skills. PDs (64.5%) and graduates (60.8%) favored teaching leadership skills during fellowship, with PDs favoring mentoring/coaching (75.0%), direct observation of staff clinicians (72.5%), and seminars (72.5%). Graduates favored a variety of approaches. Regarding topics to include in a leadership curriculum, PDs responded that communication skills (97.5%), team building (95.0%), professional skills (90.0%), clinic management (87.5%), strategies to impact the delivery of endocrinology care (85.0%), and personality skills (82.5%) were most important. Graduates responded similarly, with \u3e80% agreement for each topic. Finally, most PDs (89%) expressed a desire to incorporate more leadership training into their programs. Conclusions: Our survey suggests a need for leadership training in endocrinology fellowships. More work is needed to determine how best to meet this need

    Design and integration of lower ports for ITER diagnostic systems

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    All around the ITER vacuum vessel, forty-four ports will provide access to the vacuum vessel for remotehandling operations, diagnostic systems, heating, and vacuum systems: 18 upper ports, 17 equatorialports, and 9 lower ports. Among the lower ports, three of them will be used for the remote handlinginstallation of the ITER divertor. Once the divertor is in place, these ports will host various diagnosticsystems mounted in the so-called diagnostic racks. The diagnostic racks must allow the support andcooling of the diagnostics, extraction of the required diagnostic signals, and providing access and main-tainability while minimizing the leakage of radiation toward the back of the port where the humans areallowed to enter. A fully integrated inner rack, carrying the near plasma diagnostic components, will bean stainless steel structure, 4.2 m long, with a maximum weight of 10 t. This structure brings water forcooling and baking at maximum temperature of 240?C and provides connection with gas, vacuum andelectric services. Additional racks (placed away from plasma and not requiring cooling) may be requiredfor the support of some particular diagnostic components. The diagnostics racks and its associated exvessel structures, which are in its conceptual design phase, are being designed to survive the lifetimeof ITER of 20 years. This paper presents the current state of development including interfaces, diagnos-tic integration, operation and maintenance, shielding requirements, remote handling, loads cases anddiscussion of the main challenges coming from the severe environment and engineering requirements

    ATLAS Run 1 searches for direct pair production of third-generation squarks at the Large Hadron Collider

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    Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at s=8TeV\sqrt{s}=8\,\mathrm TeV{} with the ATLAS detector

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    Mount St. Helens

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    Postcard of Mount St. Helens erupting. | Mount St. Helens located in southwest Washington. This 9,677 foot mountain, a dormant volcano for over 100 years, began volcanic activity in early 1980. Mount St. Helens is the first active volcano in the continental United States in over 60 years.photographic postcard
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