检索结果-南通市图书馆

ANISOTROPIC EQ^(ROT)_(1) FINITE ELEMENT APPROXIMATION FOR A MULTI-TERM TIME-FRACTIONAL MIXED SUB-DIFFUSION AND DIFFUSION-WAVE EQUATION

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2023年第3期41卷 458-481页

作者： huijun fan Yanmin Zhao Fenling Wang Yanhua Shi Fawang Liu School of Science Xuchang UniversityXuchang 461000China School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China Henan Joint International Research Laboratory of High Performance Computation for Complex Systems Xuchang 461000China School of Mathematical Sciences Queensland University of TechnologyBrisbane QLD 4001Australia School of Mathematics and Statistics Fuzhou UniversityFuzhou 350108China

By employing EQ^(ROT)_(1) nonconforming finite element,the numerical approximation is presented for multi-term time-fractional mixed sub-diffusion and diffusion-wave equation on anisotropic *** with the multi-term time-fractional sub-diffusion equation or diffusion-wave equation,the mixed case contains a special time-space coupled derivative,which leads to many difficulties in numerical ***,a fully discrete scheme is established by using nonconforming finite element method(FEM)in spatial direction and L1 approximation coupled with Crank-Nicolson(L1-CN)scheme in temporal ***,the fully discrete scheme is proved to be unconditional ***,convergence and superclose results are derived by using the properties of EQ^(ROT)_(1) nonconforming finite ***'s more,the global superconvergence is obtained via the interpolation postprocessing ***,several numerical results are provided to demonstrate the theoretical analysis on anisotropic meshes.

关键词： Multi-term time-fractional mixed sub-diffusion and diffusion-wave equation Nonconforming FEM L1-CN scheme Anisotropic meshes Convergence and superconvergence

Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第8期41卷 1465-1482页

作者： Jiazhen ZHAO Shengping HE Ke fan huijun WANG Fei LI Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway School of Atmospheric Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research Bergen 5007Norway Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions ***, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained).

关键词： wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence

膝骨关节炎治疗药物——lorecivivint

在线全文

学校读者我要写书评

暂无评论

临床药物治疗杂志 2024年第6期22卷 6-13页

作者：陈婕杨军田娜娜陈媛广梅范慧君王红军北京泰德制药股份有限公司创新药部北京100176

lorecivivint是一种调节Wnt通路CLK/DYRK激酶的新型小分子抑制剂,通过关节腔注射给药,治疗膝骨关节炎,目前正在美国进行Ⅲ期临床试验。已完成的临床试验结果显示,lorecivivint安全性和耐受性良好,具有缓解疼痛和改善膝关节功能的显著疗... 详细信息

lorecivivint是一种调节Wnt通路CLK/DYRK激酶的新型小分子抑制剂,通过关节腔注射给药,治疗膝骨关节炎,目前正在美国进行Ⅲ期临床试验。已完成的临床试验结果显示,lorecivivint安全性和耐受性良好,具有缓解疼痛和改善膝关节功能的显著疗效,长期治疗可改善关节结构,是具有潜力的疾病改善型骨关节炎药物。本文就lorecivivint的基本信息、作用机制、药动学和临床研究进展等方面进行概述。

关键词： lorecivivint Wnt通路 CLK/DYRK激酶抑制剂膝骨关节炎疾病改善型骨关节炎药物

The Moduli Space in the Gauged Linear Sigma Model

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2017年第4期38卷 913-936页

作者： huijun fan Tyler JARVIS Yongbin RUAN School of Mathematical Sciences Peking University Beijing 100871 China. Department of Mathematics Brigham Young University Provo UT 84602 USA. Department of Mathematics University of Michigan Ann Arbor MI 48105 USA.

This is a survey article for the mathematical theory of Witten's Gauged Linear Sigma Model, as developed recently by the authors. Instead of developing the theory in the most general setting, in this paper the authors... 详细信息

关键词：非线性σ模型模空间度量数学理论作者

Seasonal prediction of extreme high-temperature days over the Yangtze River basin

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第7期67卷 2137-2147页

作者： Shifeng PAN Zhicong YIN Mingkeng DUAN Tingting HAN Yi fan Yangyang HUANG huijun WANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Extreme high temperatures occur frequently over the densely populated Yangtze River basin(YRB)in China during summer,significantly impacting the local economic development and ecological ***,accurate prediction of extreme high-temperature days in this region remains a ***,the Climate Forecast System Version 2(CFSv2)exhibits poor performance in this ***,based on the interannual increment approach,we develop a hybrid seasonal prediction model over the YRB(HM_(YRB))to improve the prediction of extreme high-temperature days in *** HM_(YRB)relies on the following four predictors:the observed preceding April-May snowmelt in north western Europe;the snow depth in March over the central Siberian Plateau;the CFSv2-forecasted concurrent summer sea surface temperatures around the Maritime Continent;and the 200-hPa geopotential height over the Tibetan *** HM_(YRB)indicates good capabilities in predicting the interannual variability and trend of extreme high-temperature days,with a markable correlation coefficient of 0.58 and a percentage of the same sign(PSS)of 76% during 1983-2015 in the one-year-out ***,the HM_(YRB) maintains high PSS skill(86%)and robustness in the independent prediction period(2016-2022).Furthermore,the HM_(YRB) shows a good performance for years with high occurrence of extreme high-temperature days,with a hit ratio of 40%.These predictors used in HM_(YRB)are beneficial in terms of the prediction skill for the average daily maximum temperature in summer over the YRB,albeit with biases existing in the *** study provides promising insights into the prediction of 2022-like hot extremes over the YRB in China.

关键词： Hot extremes Yangtze River basin CFSv2 Seasonal prediction One-year-out cross-validation

同方期刊数据库

Relative Impacts of Sea Ice Loss and Atmospheric Internal Variability on the Winter Arctic to East Asian Surface Air Temperature Based on Large-Ensemble Simulations with NorESM2

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第8期41卷 1511-1526页

作者： Shengping HE Helge DRANGE Tore FUREVIK huijun WANG Ke fan Lise Seland GRAFF Yvan J.ORSOLINI Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5020Norway Nansen Environmental and Remote Sensing Center Bergen 5007Norway Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 211544China Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 511458China School of Atmospheric Science Sun Yat-Sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Norwegian Meteorological Institute Oslo 0313Norway Norwegian Institute for Air Research Kjeller 2007Norway

To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simulations carried out by the Norwegian Earth System Model with a coupled atmosphere–land surface model, forced by seasonal sea ice conditions from preindustrial, present-day, and future periods. Each ensemble member within the same set uses the same forcing but with small perturbations to the atmospheric initial state. Hence, the difference between the present-day(or future) ensemble mean and the preindustrial ensemble mean provides the ice-loss-induced response, while the difference of the individual members within the present-day(or future) set is the effect of atmospheric internal variability. Results indicate that both present-day and future sea ice loss can force a negative phase of the Arctic Oscillation with a WACE pattern in winter. The magnitude of ice-induced Arctic warming is over four(ten) times larger than the ice-induced East Asian cooling in the present-day(future) experiment;the latter having a magnitude that is about 30% of the observed cooling. Sea ice loss contributes about 60%(80%) to the Arctic winter warming in the present-day(future) experiment. Atmospheric internal variability can also induce a WACE pattern with comparable magnitudes between the Arctic and East Asia. Ice-lossinduced East Asian cooling can easily be masked by atmospheric internal variability effects because random atmospheric internal variability may induce a larger magnitude warming. The observed WACE pattern occurs as a result of both Arctic sea ice loss and atmospheric internal variability, with the former dominating Arctic warming and the latter dominating East Asian cooling.

关键词： Arctic sea ice loss warm Arctic–cold East Asia atmospheric internal variability large-ensemble simulation NorESM2 PAMIP

Hydraulic fracturing behaviors of shale under coupled stress and temperature conditions simulating different burial depths

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2024年第6期34卷 783-797页

作者： Qin Zhou Zheming Zhu Wei Liu huijun Lu Zidong fan Xiaofang Nie Cunbao Li Jun Wang Li Ren MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Downhole Operating Company CNPC Chuanqing Drilling and Exploration Engineering Co.Ltd.Shenzhen 518060China School of Architecture and Civil Engineering Xihua UniversityChengdu 610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Shenzhen UniversityShenzhen 518060China

Fracture propagation in shale under in situ conditions is a critical but poorly understood mechanical process in hydraulic fracturing for deep shale gas *** address this,hydraulic fracturing experiments were conducted on hollow double-wing crack specimens of the Longmaxi shale under conditions simulating the ground surface(confining pressure rcp=0,room temperature(Tr))and at depths of 1600 m(rcp=40 MPa,Ti=70C)and 3300 m(rcp=80 MPa,high temperature Ti=110C)in the study *** in situ stress was found to significantly increase fracture toughness through constrained microcracking and particle frictional bridging *** the temperature enhances rather than weakens the fracture resistance because it increases the grain debonding length,which dissipates more plastic energy and enlarges grains to close microdefects and generate compressive stress to inhibit ***,the fracture toughness anisotropy in the shale was found to be nearly constant across burial depths,despite reported variations with increasing confining *** water was not found to be as important as the in situ environment in influencing shale *** findings emphasize the need to test the fracture toughness of deep shales under coupled in situ stress and temperature conditions rather than focusing on either in situ stress or temperature alone.

关键词： Hydraulic fracturing Fracture toughness Shale Anisotropy Deep rock mechanics

Witten's D_4 Integrable Hierarchies Conjecture

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2016年第2期37卷 175-192页

作者： huijun fan Amanda FRANCIS Tyler JARVIS Evan MERRELL Yongbin RUAN School of Mathematical Sciences Peking University Department of Mathematics Brigham Young University Department of Mathematics University of Michigan Ann Arbor the Yangtz Center of Mathematics at Sichuan University

The authors prove that the total descendant potential functions of the theory of fan-Jarvis-Ruan-Witten for D4 with symmetry group J and for D4T with symmetry group Gmax, respectively, are both tau-functions of the D4 Kac-Wakimoto/Drinfeld-Sokolov hierarchy. This completes the proof, begun in the article by fan-Jarvis-Ruan（2013）, of the Witten Integrable Hierarchies Conjecture for all simple（ADE） singularities.

关键词：可积模型猜想 D4 tau蛋白潜在功能功能层次对称群 ADE

LG/CY Correspondence Between tt^(*)Geometries

在线全文

学校读者我要写书评

暂无评论

Communications in Mathematical Research 2021年第3期37卷 297-348页

作者： huijun fan Tian Lan Zongrui Yang School of Mathematical Sciences Peking UniversityBeijing 100871China

The concept of tt^(*)geometric structure was introduced by physicists(see[4,9]and references therein),and then studied firstly in mathematics by ***[26].It is believed that the tt*geometric structure contains the whole genus 0 information of a two dimensional topological field *** this paper,we propose the LG/CY correspondence conjecture for tt^(*)geome-try and obtain the following *** f∈￠[z_(0),…,z_(n+1)]be a nondegenerate homogeneous polynomial of degree n+2,then it defines a Calabi-Yau model represented by a Calabi-Yau hypersurface X_(f)in(￠P)^(n+1)or a Landau-Ginzburg model represented by a hypersurface singularity(￠^(n+2),f),both can be written as a tt^(*)*** proved that there exists a tt^(*)substructure on Landau-Ginzburg side,which should correspond to the tt*structure from variation of Hodge structures in Calabi-Yau *** build the isomorphism of almost all structures in tt^(*)geometries between these two models except the isomorphism between real structures.

关键词： tt^(*)geometry Landau-Ginzburg/Calabi-Yau correspondence variation of Hodge structures