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Active learning of deep surrogates for PDEs:application to metasurface design

2005年

作者： steven l. Gersen Martha B. Keagle

来源：畅想之星图书光盘版（南... 评论

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npj Computational Materials 2020年第1期6卷 312-318页

作者： Raphaël Pestourie Youssef Mroueh Thanh V.Nguyen Payel Das steven G.Johnson Department of Mathematics Massachusetts Institute of Technology77 Massachusetts AveCambridgeMA 02139USA IBM Research AI IBM Thomas J Watson Research CenterYorktown HeightsYorktownNY 10598USA MIT-IBM Watson AI lab CambridgeMA 02139USA Iowa State University AmesIA 50011USA

Surrogate models for partial differential equations are widely used in the design of metamaterials to rapidly evaluate the behavior of composable ***,the training cost of accurate surrogates by machine learning can rapidly increase with the number of *** photonic-device models,we find that this training becomes especially challenging as design regions grow larger than the optical *** present an active-learning algorithm that reduces the number of simulations required by more than an order of magnitude for an NN surrogate model of optical-surface components compared to uniform random *** show that the surrogate evaluation is over two orders of magnitude faster than a direct solve,and we demonstrate how this can be exploited to accelerate large-scale engineering optimization.

关键词： optimization surrogate faster

A Survey of Unbalanced Flow Diagnostics and Their Application

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Advances in Atmospheric Sciences 2000年第2期17卷 165-183页

作者： Fuqing Zhang steven E. Koch Christopher A. Davis and Michael l. Kaplan Department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh USA National Center for Atmospheric Research Boulder USA

This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equation, generalized omega-equation, and departure from fields obtained by potential vorticity (PV) inversion. The basic thoery, assumptions as well as implementation and limitations for each of the tools are all discussed. These tools are applied to high—resolution mesoscale model data to assess the role of unbalanced dynamics in the generation of a mesoscale gravity wave event over the East Coast of the United States. Comparison of these tools in this case study shows that these various methods agree to a large extent with each other though they differ in details. Key words Unbalanced flow - Geostrophic adjustment - Gravity waves - Nonlinear balance equation - Potential vorticity inversion - Omega equations - Rossby number This research was conducted under support from NSF grant ATM-9700626 of the United States. The numerical computations described herein were performed on the Cray T90 at the North Carolina Supercomputing Center and the Cray supercomputer at the NCAR Scientific Computing Division, which also provided the initialization fields for the MM5. Thanks are extended to Mark Stoelinga at University of Washington for the RIP post-processing package.

关键词： Unbalanced flow Geostrophic adjustment Gravity waves Nonlinear balance equation Potential vorticity inversion Omega equations Rossby number

Androgens and esophageal cancer: What do we know?

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World Journal of Gastroenterology 2015年第20期21卷 6146-6156页

作者： Olga A Sukocheva Bin li steven l Due Damian J Hussey David I Watson Flinders University Department of Surgery Flinders Medical Centre

Significant disparities exist between genders for the development and progression of several gastrointestinal(GI) diseases including cancer. Differences in incidence between men vs women for colon, gastric and hepatocellular cancers suggest a role for steroid sex hormones in regulation of GI carcinogenesis. Involvement of intrinsic gender-linked mechanisms is also possible for esophageal adenocarcinoma as its incidence is disproportionally high among men. However, the cause of the observed gender differences and the potential role of androgens in esophageal carcinogenesis remains unclear, even though the cancer-promoting role of androgen receptors(AR) shown in other cancers such as prostate and bladder suggests this aspect warrants exploration. Several studies have demonstrated expression of ARs in esophageal cancer. However, only one study has suggested a potential link between AR signaling and outcome- poorer prognosis. Two groups have analyzed data from cohorts with prostate cancer and one of these found a decreased incidence of esophageal squamous and adenocarcinoma after androgen deprivation therapy. However, very limited information is available about the effects of androgen and AR-initiated signaling on esophageal cancer cell growth in vitro and in vivo. Possible mechanisms for androgens/AR involvement in the regulation of esophageal cancer growth are considered, and the potential use of AR as a prognostic factor and clinical target is highlighted, although insufficient evidence is available to support clinical trials of novel therapies. As esophageal adenocarcinoma is a gender linked cancer with a large male predominance further studies are warranted to clarify the role of androgens and ARs in shaping intracellular signaling and genomic responses in esophageal cancer.

关键词： Esophageal cancer Androgens Androgenreceptor

N-acetylcysteine treats intravenous amiodarone induced liver injury

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World Journal of Gastroenterology 2015年第9期21卷 2816-2819页

作者： Matthew l Mudalel Kartikeya P Dave James P Hummel steven F Solga Department of Medicine Division of GastroenteorlogySt. Luke’s University Hospital and Temple School of MedicineBethlehemPA 18015United States Department of Medicine Montefiore Medical CenterBronxNY 10461United States Department of Medicine Division of Cardiology University of North Carolina Chapel Hill NC 27514United States

We report a case of intravenous(IV) amiodarone drug induced liver injury(DIlI).The patient received IV N-acetylcysteine(NAC) which resulted in a rapid improvement in liver *** the specific mechanisms for the pathogenesis of IV amiodaroneDIlI and the therapeutic action of IV NAC are both unknown, this case strongly implies at least some *** IV amiodarone is indicated for the treatment of serious cardiac arrhythmias in an intensive care unit setting, some degree of ischemic hepatitis is likely a cofactor in most cases.

关键词： N-acetylcysteine Amiodarone Drug induced liver inj

A refutation of reported levallois technology from Guanyindong Cave in south China

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National Science Review 2019年第6期6卷 1094-1096页

作者： Feng li Yinghua li Xing Gao steven l.Kuhn Eric Boёda John W.Olsen Key laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences CAS Center for Excellence in life and Paleoenvironment School of History Wuhan University University of Chinese Academy of Sciences School of Anthropology University of Arizona C.N.R.S.-UMR7041 Anthropologie des techniques des espaces et des territoires au Plio-Pléistocène Maison Archéologie et Ethnologie

As one of the most complex forms of lithic technology known for the Paleolithic, research on the levallois stoneknapping method is critically relevant to our understanding of the cognitive abilities and depth of planning capabilities of archaic hominins, as well as the diffusion of knowledge and social learning in Pleistocene societies. For decades,

关键词： A refutation of reported levallois technology from Guanyindong Cave in south China

Properties of diamond tool binders with fine carbonyl Ni powder additions

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金刚石与磨料磨具工程 2008年第S1期28卷 148-151页

作者： stephenson T F Korotkin M Metcalfe S 2060 Hadwen Road Mississauga Ontario L5K 1Z9 Canada

Fine Ni powder is often added to Co and bronze-based metal binder powders for diamond tool *** is a lower cost substitute for extra-fine Co powder and increases the toughness of Co-Fe diamond binders at the expense of lower hardness and bend *** bronze-based diamond binder segments,Ni increases hardness and yield *** grades of Ni powder are used commercially with both Co and bronze-based diamond *** paper compares properties of diamond binders containing carbonyl Ni powders including standard Inco(?) T255,T123 PM and T 110 *** materials were made by ball milling or dry mixing of the fine carbonyl Ni and Fe powders with either XF Co or air atomized bronze(90/10 Cu/Sn) ***-based powder blends were hot pressed at 20～35 MPa and 700℃to 900℃.Bronze-based powder blends were cold pressed and sintered at 840℃.Apparent density,apparent hardness and bend strength(TRS) were compared for different binder compositions and processing conditions.

关键词： binder Ni powder additive diamond tool

Deep Rank-Based Average Pooling Network for Covid-19 Recognition

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Computers, Materials & Continua 2022年第2期70卷 2797-2813页

作者： Shui-Hua Wang Muhammad Attique Khan Vishnuvarthanan Govindaraj steven l.Fernandes Ziquan Zhu Yu-Dong Zhang School of Mathematics and Actuarial Science University of LeicesterLE17RHUK Department of Computer Science HITEC University TaxilaTaxilaPakistan Department of Biomedical Engineering Kalasalingam Academy of Research and Education626126Tamil NaduIndia Department of Computer Science Design&JournalismCreighton UniversityOmahaNebraskaUSA Science in Civil Engineering University of FloridaGainesvilleFloridaFL 32608USA School of Informatics University of LeicesterUK

(Aim)To make a more accurate and precise COVID-19 diagnosis system,this study proposed a novel deep rank-based average pooling network(DRAPNet)model,i.e.,deep rank-based average pooling network,for COVID-19 recognition.(Methods)521 subjects yield 1164 slice images via the slice level selection *** the 1164 slice images comprise four categories:COVID-19 positive;community-acquired pneumonia;second pulmonary tuberculosis;and healthy *** method firstly introduced an improved multiple-way data ***,an n-conv rankbased average pooling module(NRAPM)was proposed in which rank-based pooling—particularly,rank-based average pooling(RAP)—was employed to avoid ***,a novel DRAPNet was proposed based on NRAPM and inspired by the ***-CAM was used to generate heatmaps and gave our AI model an explainable analysis.(Results)Our DRAPNet achieved a micro-averaged F1 score of 95.49%by 10 runs over the test *** sensitivities of the four classes were 95.44%,96.07%,94.41%,and 96.07%,*** precisions of four classes were 96.45%,95.22%,95.05%,and 95.28%,*** F1 scores of the four classes were 95.94%,95.64%,94.73%,and 95.67%,***,the confusion matrix was given.(Conclusions)The DRAPNet is effective in diagnosing COVID-19 and other chest infectious *** RAP gives better results than four other methods:strided convolution,l2-norm pooling,average pooling,and max pooling.

关键词： COVID-19 rank-based average pooling deep learning deep neural network

Pharmacologic inhibition of mTORC1 mimics dietary protein restriction in a mouse model of lactation

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Journal of Animal Science and Biotechnology 2021年第2期12卷 729-738页

作者： Virginia l.Pszczolkowski steven J.Halderson Emma J.Meyer Amy lin Sebastian I.Arriola Apelo Department of Animal and Dairy Sciences University of Wisconsin-MadisonMadisonWIUSA Endocrinology and Reproductive Physiology Graduate Training Program University of Wisconsin-MadisonMadisonWIUSA

Background:Understanding the mechanisms of N utilization for lactation can lead to improved requirement estimates and increased efficiency,which modern dairy diets currently fail to *** mechanistic target of rapamycin complex 1(mTORC1)is a central hub of translation regulation,processing extra-and intra-cellular signals of nutrient availability and physiological state,such as amino acids and *** hypothesized that dietary amino acids regulate lactation through mTORC1,such that inhibition of mTORC1 will lead to decreased lactation performance when amino acids are not *** objectives were to assess lactation performance in lactating mice undergoing dietary and pharmacologic interventions designed to alter mTORC1 ***:First lactation mice(N=18;n=6/treatment)were fed an adequate protein diet(18%crude protein),or an isocaloric protein-restricted diet(9%crude protein)from the day after parturition until lactation day 13.A third group of mice was fed an adequate protein diet and treated with the mTORC1 inhibitor rapamycin(4 mg/kg every other day)intraperitoneally,with the first two groups treated with vehicle as *** and pups were weighed daily,and feed intake was recorded every other *** production was measured every other day beginning on lactation day 4 by the weigh-suckle-weigh *** were collected after fasting and ***:Milk production and pup weight were similarly decreased by both protein restriction and rapamycin treatment,with final production at 50%of control(P=0.008)and final pup weight at 85%of control(Plation of mTORC1’s downstream targets were decreased by protein restriction and rapamycin treatment(Ple very little effect was observed in the liver of rapamycin treated mice,and none by protein ***:Overall,sufficient supply of dietary amino acids was unable to maintain lactation performance status in mice with pharmacologically reduced mam

关键词： Amino acids lactation Mammary Mouse model mTORC1 Rapamycin

Compact and robust supercontinuum generation and post-compression using multiple thin plates

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High Power laser Science and Engineering 2021年第4期9卷 234-241页

作者： Xinhua Xie Yunpei Deng steven l.Johnson Swiss FEl Paul Scherrer Institute5232 Villi genSwitzerland Institute for Quantum Electronics Physics DepartmentETH ZurichETH Zurich8093 ZurichSwitzerland

We report on compact and robust supercontinuum generation and post-compression using transmission of light through multiple thin solid plates at the Swiss FEl X-ray free-electron laser facility.A single stage consisting of three thin plates followed by a chirped mirror compressor achieves compression of initially 30-fs pulses with 800-nm center wavelength to sub-10-fs *** also demonstrate a two-stage implementation to compress the pulses further to sub-5-fs *** the two-stage setup,the generated supercontinuum includes wavelengths ranging from 500 to 1100 *** multiplate setup is compact,robust,and stable,which makes it ideal for applications at free-electron laser facilities such as pump-probe experiments and laser-arrival timing tools.

关键词： post-compression self-phase modulation supercontinuum generation