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A REDUCED ORDER SCHWARZ METHOD FOR NONLINEAR MULTISCALE ELLIPTIC EQUATIONS BASED ON TWO-LAYER NEURAL NETWORKS

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journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen Zhiyan Ding Qin Li stephen j.Wright Mathematics Department University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics Department and Discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences Department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PDEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz ***,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each *** leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary *** method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace *** both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks Do-main decomposition

The effects of local variations in conditions on carbon storage and release in the continental mantle

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National Science Review 2024年第6期11卷 22-36页

作者： stephen F.Foley Chunfei Chen Dorrit E.jacob School of Natural Sciences Macquarie University Research School of Earth Sciences Australian National University State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. Future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

关键词： lithospheric mantle carbonate melts deep carbon cycle craton destruction continental rifts

Comparison of methods for deriving phenotypes from incomplete observation data with an application to age at puberty in dairy cattle

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journal of Animal Science and Biotechnology 2024年第2期15卷 535-545页

作者： Melissa A.stephen Chris R.Burke jennie E.Pryce Nicole M.Steele Peter R.Amer Susanne Meier Claire V.C.Phyn Dorian j.Garrick DairyNZ Ltd 605 Ruakura RoadHamilton 3240New Zealand AL Rae Centre for Genetics and Breeding-Massey University RuakuraHamilton 3214New Zealand Agriculture Victoria Research AgriBioCentre for AgriBioscienceBundooraVictoria 3083Australia School of Applied Systems Biology La Trobe UniversityBundooraVictoria 3083Australia AbacusBio DunedinNew Zealand

Background Many phenotypes in animal breeding are derived from incomplete measures,especially if they are challenging or expensive to measure *** include time-dependent traits such as reproductive status,or *** measures for these traits result in phenotypes that are subject to left-,interval-and rightcensoring,where phenotypes are only known to fall below an upper bound,between a lower and upper bound,or above a lower bound *** we compare three methods for deriving phenotypes from incomplete data using age at first elevation(>1 ng/mL)in blood plasma progesterone(AGEP4),which generally coincides with onset of puberty,as an example *** We produced AGEP4 phenotypes from three blood samples collected at about 30-day intervals from approximately 5,000 Holstein–Friesian or Holstein–Friesian×jersey cross-bred dairy heifers managed in 54 seasonal-calving,pasture-based herds in New *** used these actual data to simulate 7 different visit scenarios,increasing the extent of censoring by disregarding data from one or two of the three *** methods for deriving phenotypes from these data were explored:1)ordinal categorical variables which were analysed using categorical threshold analysis;2)continuous variables,with a penalty of 31 d assigned to right-censored phenotypes;and 3)continuous variables,sampled from within a lower and upper bound using a data augmentation *** Credibility intervals for heritability estimations overlapped across all methods and visit scenarios,but estimated heritabilities tended to be higher when left censoring was *** sires with at least 5 daughters,the correlations between estimated breeding values(EBVs)from our three-visit scenario and each reduced data scenario varied by method,ranging from 0.65 to *** estimated breed effects also varied by method,but breed differences were smaller as phenotype censoring *** Our results indicate that using

关键词： Cattle Gibbs sampler Markov-chain Monte Carlo(MCMC) Puberty

Error field penetration in j-TEXT tokamak based on two-fluid drift-MHD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j-TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

SARS-CoV-2 triggers Dickkopf-1(Dkk-1)modulation of T helper cells and lung pathology in mice

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Genes & Diseases 2024年第4期11卷 9-12页

作者： Yifan Wu Freedom M.Green stephen A.Shaw Lauren j.Bonilla Shannon E.Ronca Maria Elena Bottazzi Farrah Kheradmand jill E.Weatherhead Department of Pathology&Immunology One Baylor PlazaHoustonTX 77030USA Department of Pediatrics One Baylor PlazaHoustonTX 77030USA Department of Medicine One Baylor PlazaHoustonTX 77030USA National School of Tropical Medicine One Baylor PlazaHoustonTX 77030USA Molecular Virology&Microbiology One Baylor PlazaHoustonTX77030USA Biologyof Inflammation Center Baylor College of MedicineOne BaylorPlazaHoustonTX77030USA Michael E.DeBakey VA Center for Translational Research on Inflammatory Diseases HoustonTX 77030USA

Severe acute respiratory syndrome coronavirus 2(SARSCov-2)is the etiologic agent of the coronavirus disease 19(COVID-19)*** viral infections like SARS-CoV-2,a robust anti-viral type 1 immune response,including upregulation of type 1 CD4+T helper cells(Th1),is required for effective viral clearance while minimizing end-organ pathology and collateral tissue damage.

关键词： pathology acute respiratory

A Modified Lagrange Method for Solving Convex Quadratic Optimization Problems

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Open journal of Optimization 2024年第1期13卷 1-20页

作者： Twum B. stephen Avoka john Christian j. Etwire School of Mathematical Science C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Mathematics University for Development Studies Tamale Ghana

In this paper, a modified version of the Classical Lagrange Multiplier method is developed for convex quadratic optimization problems. The method, which is evolved from the first order derivative test for optimality of the Lagrangian function with respect to the primary variables of the problem, decomposes the solution process into two independent ones, in which the primary variables are solved for independently, and then the secondary variables, which are the Lagrange multipliers, are solved for, afterward. This is an innovation that leads to solving independently two simpler systems of equations involving the primary variables only, on one hand, and the secondary ones on the other. Solutions obtained for small sized problems (as preliminary test of the method) demonstrate that the new method is generally effective in producing the required solutions.

关键词： Quadratic Programming Lagrangian Function Lagrange Multipliers Optimality Conditions Subsidiary Equations Modified Lagrange Method

Investigating explainable transfer learning for battery lifetime prediction under state transitions

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eScience 2024年第5期4卷 132-142页

作者： Tianze Lin Sihui Chen stephen jHarris Tianshou Zhao Yang Liu jiayu Wan Global Institute of Future Technology Shanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech Energy Institute for Carbon Neutrality Southern University of Science and TechnologyShenzhen 518055China Energy Storage and Distributed Resources Division Lawrence Berkeley National LabBerkeleyCA 94720USA Data Science Research CenterDuke Kunshan UniversityNo.8 Duke AvenueKunshan 215316China Center for Advanced Energy System and Reliability Shanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240China

Battery lifetime prediction at early cycles is crucial for researchers and manufacturers to examine product quality and promote technology *** learning has been widely utilized to construct data-driven solutions for high-accuracy ***,the internal mechanisms of batteries are sensitive to many factors,such as charging/discharging protocols,manufacturing/storage conditions,and usage *** factors will induce state transitions,thereby decreasing the prediction accuracy of data-driven *** learning is a promising technique that overcomes this difficulty and achieves accurate predictions by jointly utilizing information from various ***,we develop two transfer learning methods,Bayesian Model Fusion and Weighted Orthogonal Matching Pursuit,to strategically combine prior knowledge with limited information from the target dataset to achieve superior prediction *** our results,our transfer learning methods reduce root-mean-squared error by 41%through adapting to the target ***,the transfer learning strategies identify the variations of impactful features across different sets of batteries and therefore disentangle the battery degradation mechanisms and the root cause of state transitions from the perspective of data *** findings suggest that the transfer learning strategies proposed in our work are capable of acquiring knowledge across multiple data sources for solving specialized issues.

关键词： Battery life prediction Transfer learning State transitions Explainability Degradation mechanism

Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older

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journal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： Erik A.Willis stephen D.Herrmann Mary Hastert Chelsea L.Kracht Tiago V.Barreira john M.Schuna jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy j.Brown Barbara E.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA Exercise Science Department Syracuse UniversitySyracuseNY 13244USA School of Exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of Exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human Movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older *** developed a website to present the OA Compendium MET_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice.

关键词： Energy expenditure Exercise MET Older adults

Large potential of strengthening the land carbon sink in China through anthropogenic interventions

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Science Bulletin 2024年第16期69卷 2622-2631页

作者： Xu Yue Hao Zhou Yang Cao Hong Liao Xiaofei Lu Zhen Yu Wenping Yuan Zhu Liu Yadong Lei stephen Sitch jürgen Knauer Huijun Wang jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&Technology(NUIST)Nanjing 210044China College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China jiangsu Nanjing Environmental Monitoring Center Nanjing 210013China Key Laboratory of Agrometeorology of jiangsu Province Institute of EcologySchool of Applied MeteorologyNUISTNanjing 210044China Institute of Carbon Neutrality Sino-French Institute for Earth System ScienceCollege of Urban and Environmental SciencesPeking UniversityBeijing 100871China Department of Earth System Science Tsinghua UniversityBeijing 100084China State Key Laboratory of Severe Weather and Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China College of Life and Environmental Sciences University of ExeterExeter EX44RJUK Hawkesbury Institute for the Environment Western Sydney UniversityPenrith 2751Australia Key Laboratory of Meteorological Disaster Ministry of EducationJoint International Research Laboratory of Climate and Environment ChangeCollaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNUISTNanjing 210044China

The terrestrial ecosystem in China mitigates 21%-45%of the national contemporary fossil fuel CO_(2) emissions every *** and strengthening the land carbon sink is essential for reaching China’s target of carbon ***,this sink is subject to large uncertainties due to the joint impacts of climate change,air pollution,and human ***,we explore the potential of strengthening land carbon sink in China through anthropogenic interventions,including forestation,ozone reduction,and litter removal,taking advantage of a well-validated dynamic vegetation model and meteorological forcings from 16 climate *** anthropogenic interventions,considering Shared Socioeconomic Pathways(SSP)scenarios,the land sink is projected to be 0.26-0.56 Pg C a^(-1) at 2060,to which climate change contributes 0.06-0.13 Pg C a^(-1) and CO_(2) fertilization contributes 0.08-0.44 Pg C a^(-1) with the stronger effects for higher emission *** anthropogenic interventions,under a close-to-neutral emission scenario(SSP1-2.6),the land sink becomes 0.47-0.57 Pg C a^(-1) at 2060,including the contributions of 0.12 Pg C a^(-1) by conservative forestation,0.07 Pg C a^(-1) by ozone pollution control,and 0.06-0.16 Pg C a^(-1) by 20%litter removal over planted *** sink can mitigate 90%-110% of the residue anthropogenic carbon emissions in 2060,providing a solid foundation for the carbon neutrality in China.

关键词： Carbon sink forestation Ozone Litter removal