期刊文献+
共找到15篇文章
< 1 >
每页显示 20 50 100
Sodium-rich volcanic rocks and their relationships with iron deposits in the Aqishan-Yamansu belt of Eastern Tianshan,NW China 被引量:2
1
作者 zhiyuan sun WangJingbin +5 位作者 Yuwang Wang Lingli Long Zhaohua Luo Xiaohua Deng Qitao Hu Menglong Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第2期697-713,共17页
The volcanic rocks hosting the iron deposits in the Aqishan–Yamansu metallogenic belt are sodium-rich.The geochronology,petrography,and geochemistry of minerals and sodium-rich rocks as well as the relationship betwe... The volcanic rocks hosting the iron deposits in the Aqishan–Yamansu metallogenic belt are sodium-rich.The geochronology,petrography,and geochemistry of minerals and sodium-rich rocks as well as the relationship between these rocks and the iron deposits are studied.Geochemically,the ore-hosting volcanic rocks are sodiumrich(the averages of Na2O and Na2O/K2O are 4.31 wt.%and 8.56,respectively)and belong to the calc-alkaline series.They are enriched in LREEs and LILEs(Ba,U,K,and Sr),but depleted in HFSEs(Nb,Ta,and Ti).SHRIMP zircon U–Pb dating of the crystal tuff in the Aqishan Formation and the dacite in the Tugutu Bulak Formation yields ages of 337.52.3 Ma(n?15,MSWD?0.85)and 313.03.3 Ma(n?13,MSWD?0.74),respectively,indicating that the sodium-rich volcanic rocks formed from the early–late Carboniferous.Electron microprobe data from plagioclases demonstrate that albites and/or oligoclases were formed in the basic–intermediate–acid volcanic rocks.Two stages of albitization are identified,and the latter is likely attributed to the dissolution of iron in the Aqishan–Yamansu belt.The sodium-rich volcanic rocks probably formed by the interaction between volcanic lava and seawater after volcanoes erupted on the seafloor;meanwhile,the albites formed by element substitution in a low-metamorphic environment.The spatiotemporal coupling relationship between sodium-rich volcanic rocks and iron deposits in the Aqishan–Yamansu belt is favorable.Iron dissolved from the dark minerals of basic–intermediate volcanic rocks through sodium metasomatism is one of the material sources for the iron deposits. 展开更多
关键词 Sodium-rich volcanic rock GEOCHRONOLOGY Rock geochemistry Yamansu metallogenic belt Eastern tianshan orogenic belt
下载PDF
In-situ LA-ICP-MS trace element and oxygen isotope signatures of magnetite from the Yamansu deposit,NW China,and their significance 被引量:1
2
作者 zhiyuan sun Yuwang Wang Lingli Long 《Acta Geochimica》 EI CAS CSCD 2020年第5期599-615,共17页
The Yamansu iron deposit is hosted in submarine volcanic rocks in the Aqishan–Yamansu belt of Eastern Tianshan,NW China.A geological cross-section for the Carboniferous strata in the ore district shows that ore bodie... The Yamansu iron deposit is hosted in submarine volcanic rocks in the Aqishan–Yamansu belt of Eastern Tianshan,NW China.A geological cross-section for the Carboniferous strata in the ore district shows that ore bodies in the Yamansu deposit are hosted in andesitic crystal tuff of the third cycle of the Carboniferous Yamansu Formation.This indicates an association between mineralization and volcanism.The orebodies are strata bound and lensoid and generally share the occurrence state of the host rocks.Magnetite mineralization mainly occurs asbreccia ores,ores in the mineralized volcanic rocks,massive ores,and sulfide-rich ores according to their structures and sequences of formation.Trace element compositions of magnetite from various types of ores were determined by LA-ICP-MS.The dataset indicates thatdifferent types of magnetite havedistinct trace element contents correlated to their formation environments.Magnetite crystals from breccia ores have high Ti,Ni,V,Cr,and Co and low Si,Al,Ca,and Mg contents,indicating crystallization from a volcanic magmatic eruption,which is consistent with field evidence of coexisting altered volcanic breccia.Magnetite crystals from ores in the mineralized volcanic rocks have moderate Ti,Ni,V,Cr,and Co contents.In contrast,magnetite from massive ores and sulfide-rich ores have low concentrations of Ti,Cr,Ni,and V,high concentrations of Si,Al,Ca,and Mg,and evidence of hydrothermal magnetite.In-situ magnetite compositions imply a magmatic-hydrothermal process.Although d18 O values for magnetite grains from Yamansu vary(?1.3 to?7.0%),they all plot in the range field of volcanic iron deposits,and they also record a magmatic-hydrothermal process.The compositions of Yamansu magnetites are interpreted as controlled mainly by temperature,fluid,host rock buffering,oxygen fugacity,and sulfur fugacity.The metallogenic conditions of the Yamansu deposit changed from high temperature and low oxygen fugacity to low temperature and high oxygen fugacity.However,more fluid-rock reactions and higher sulfur fugacity were involved during the deposition of massive ores and sulfiderich ores. 展开更多
关键词 MAGNETITE Trace element composition LAICP-MS Oxygen isotope Yamansu iron deposit Eastern Tianshan
下载PDF
The Synthesis of Bridged Purine Dinucleoside
3
作者 Xiao Hua XU zhiyuan sun +2 位作者 Zhong Biao ZHANG Guo Chen CHI RuYu CHEN(Institute of Elemento-Organic Chemsitry,The State Key Laboratory of Elemento-organic Chemistry)(Nankai University, Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期691-692,共2页
Two bridged purine dinucleosides, bis(2-N-acetyl-6-N-alkylylene-2,6-diaminopurine-2',3',5'-triacetyl-beta-D-ribofuranoside), were synthesized fi om the reaction of the key medium 3, 2-acetylamino-6-[1-(1,2... Two bridged purine dinucleosides, bis(2-N-acetyl-6-N-alkylylene-2,6-diaminopurine-2',3',5'-triacetyl-beta-D-ribofuranoside), were synthesized fi om the reaction of the key medium 3, 2-acetylamino-6-[1-(1,2,4-triazolyl)]-purine-2',3',5'-triacetyl-beta-D-ribofuranoside with dialkylamine. 展开更多
关键词 PPM DMSO 亚砜 CL The Synthesis of Bridged Purine Dinucleoside
下载PDF
Geochronology and geochemistry of magmatic rocks in the Dongzi–Changhanboluo Pb–Zn ore district in Chifeng,Inner Mongolia,and their relationship with metallogenesis
4
作者 Hongjing Xie Yuwang Wang +2 位作者 Yunguo Zhang Wei Jiang zhiyuan sun 《Acta Geochimica》 EI CAS CSCD 2020年第5期668-697,共30页
Bulk-rock elements,isotopes,and zircon U–Pb ages are reported for magmatic rocks in the Dongzi–Changhanboluo Pb–Zn ore district in Chifeng,Inner Mongolia,China.Zircon U–Pb dating identified four stages of magmatis... Bulk-rock elements,isotopes,and zircon U–Pb ages are reported for magmatic rocks in the Dongzi–Changhanboluo Pb–Zn ore district in Chifeng,Inner Mongolia,China.Zircon U–Pb dating identified four stages of magmatism:Late Silurian gabbroic diorite(*420 Ma),Middle Permian monzonite(*274 Ma),Late Jurassic quartz porphyry and ignimbrite,breccia tuff(153–158 Ma)and Early Cretaceous andesitic porphyrite(*127 Ma).Integrating field observations,geochronology,and element and isotope geochemistry indicated a complex petrogenetic history of the magmatic rocks.The gabbroic diorite may have been sourced from EM1-type mantle.The source of the monzonite may have been mantle metasomatized by melt from the subducting plate.The Jurassic volcaniclastic rocks formed in a medium-pressure,high-temperature environment,possibly in the background of crustal thickening in a syncollisional stage and an early postcollisional stage.During this process,shaly sedimentary rocks were brought into the deep crust and heated,followed by the rapid isostatic uplift of the crust,which caused partial melting of the sedimentary rocks.Quartz monzonite porphyry and quartz porphyry formed by partial melting of mantle metasomatized by subducted sediments,but the quartz porphyry experienced high-degree differentiation and evolution.The andesitic porphyrite has characteristics similar to those of Permian monzonite,indicating that its source area was also the zone of mantle metasomatized by subducted sediment.The late Silurian and Permian magmatic rocks in this area most likely formed against a continental arc background related to the subduction of the Paleo-Asian Ocean Plate beneath the North China Plate.The Late Jurassic magmatic rocks suggest that the northern margin of the North China Craton may have been in a postcollisional setting during the Late Jurassic,with no obvious crustal thinning.The Cretaceous andesitic porphyrite may have formed against the background of lithospheric extension and thinning.According to the comprehensive analysis of geological characteristics,diagenetic and metallogenic epochs,and Pb isotope data,the formation of ore bodies in the Dongzi–Changhanboluo ore district was closely related to the Jurassic quartz porphyry. 展开更多
关键词 Pb–Zn ore district Chifeng Zircon U–Pb dating Sr–Nd–Pb isotope Relationship with metallogenesis
下载PDF
Prediction of Outcomes in Mini-Basketball Training Program for Preschool Children with Autism Using Machine Learning Models
5
作者 zhiyuan sun Fabian Herold +6 位作者 Kelong Cai Qian Yu Xiaoxiao Dong Zhimei Liu Jinming Li Aiguo Chen Liye Zou 《International Journal of Mental Health Promotion》 2022年第2期143-158,共16页
In recent years evidence has emerged suggesting that Mini-basketball training program(MBTP)can be an effec-tive intervention method to improve social communication(SC)impairments and restricted and repetitive beha-vio... In recent years evidence has emerged suggesting that Mini-basketball training program(MBTP)can be an effec-tive intervention method to improve social communication(SC)impairments and restricted and repetitive beha-viors(RRBs)in preschool children suffering from autism spectrum disorder(ASD).However,there is a considerable degree if interindividual variability concerning these social outcomes and thus not all preschool chil-dren with ASD profit from a MBTP intervention to the same extent.In order to make more accurate predictions which preschool children with ASD can benefit from an MBTP intervention or which preschool children with ASD need additional interventions to achieve behavioral improvements,further research is required.This study aimed to investigate which individual factors of preschool children with ASD can predict MBTP intervention out-comes concerning SC impairments and RRBs.Then,test the performance of machine learning models in predict-ing intervention outcomes based on these factors.Participants were 26 preschool children with ASD who enrolled in a quasi-experiment and received MBTP intervention.Baseline demographic variables(e.g.,age,body,mass index[BMI]),indicators of physicalfitness(e.g.,handgrip strength,balance performance),performance in execu-tive function,severity of ASD symptoms,level of SC impairments,and severity of RRBs were obtained to predict treatment outcomes after MBTP intervention.Machine learning models were established based on support vector machine algorithm were implemented.For comparison,we also employed multiple linear regression models in statistics.Ourfindings suggest that in preschool children with ASD symptomatic severity(r=0.712,p<0.001)and baseline SC impairments(r=0.713,p<0.001)are predictors for intervention outcomes of SC impair-ments.Furthermore,BMI(r=-0.430,p=0.028),symptomatic severity(r=0.656,p<0.001),baseline SC impair-ments(r=0.504,p=0.009)and baseline RRBs(r=0.647,p<0.001)can predict intervention outcomes of RRBs.Statistical models predicted 59.6%of variance in post-treatment SC impairments(MSE=0.455,RMSE=0.675,R2=0.596)and 58.9%of variance in post-treatment RRBs(MSE=0.464,RMSE=0.681,R2=0.589).Machine learning models predicted 83%of variance in post-treatment SC impairments(MSE=0.188,RMSE=0.434,R2=0.83)and 85.9%of variance in post-treatment RRBs(MSE=0.051,RMSE=0.226,R2=0.859),which were better than statistical models.Ourfindings suggest that baseline characteristics such as symptomatic severity of 144 IJMHP,2022,vol.24,no.2 ASD symptoms and SC impairments are important predictors determining MBTP intervention-induced improvements concerning SC impairments and RBBs.Furthermore,the current study revealed that machine learning models can successfully be applied to predict the MBTP intervention-related outcomes in preschool chil-dren with ASD,and performed better than statistical models.Ourfindings can help to inform which preschool children with ASD are most likely to benefit from an MBTP intervention,and they might provide a reference for the development of personalized intervention programs for preschool children with ASD. 展开更多
关键词 Prediction OUTCOMES mini-basketball training program autistic children machine learning models
下载PDF
A machine-learning-enabled approach for bridging multiscale simulations of CNTs/PDMS composites
6
作者 Lingjie Yu Chao Zhi +5 位作者 zhiyuan sun Hao Guo Jianglong Chen Hanrui Dong Mengqiu Zhu Xiaonan Wang 《National Science Open》 2024年第2期21-35,共15页
Benefitting from the interlaced networking structure of carbon nanotubes(CNTs),the composites of CNTs/polydimethylsiloxane(PDMS)have found extensive applications in wearable electronics.While hierarchical multiscale s... Benefitting from the interlaced networking structure of carbon nanotubes(CNTs),the composites of CNTs/polydimethylsiloxane(PDMS)have found extensive applications in wearable electronics.While hierarchical multiscale simulation frameworks exist to optimize the structure parameters,their wide applications were hindered by the high computational cost.In this study,a machine learning model based on the artificial neural networks(ANN)embedded graph attention network,termed as AGAT,was proposed.The datasets collected from the micro-scale and the macro-scale simulations are utilized to train the model.The ANN layer within the model framework is trained to pass the information from micro-scale to macro-scale,while the whole model is aimed to predict the electro-mechanical behavior of the CNTs/PDMS composites.By comparing the AGAT model with the original multiscale simulation results,the data-driven strategy is shown to be promising with high accuracy,demonstrating the potential of the machine-learning-enabled approach for the structure optimization of CNT-based composites. 展开更多
关键词 multiscale simulation machine learning material property prediction CNTs/PDMS composites
原文传递
靶场光电测量设备发展现状及展望 被引量:3
7
作者 余毅 刘震宇 +1 位作者 孙志远 刘海波 《光学学报》 EI CAS CSCD 北大核心 2023年第6期16-32,共17页
靶场光电测量设备利用光学成像采集飞行目标信息,经误差修正、时空配准、交汇计算等处理可以得到所需的目标参数,是航天器发射回收测控系统中的重要组成部分,也被广泛应用于军事目标的探测中。为了应对复杂测量条件和多样化被测目标带... 靶场光电测量设备利用光学成像采集飞行目标信息,经误差修正、时空配准、交汇计算等处理可以得到所需的目标参数,是航天器发射回收测控系统中的重要组成部分,也被广泛应用于军事目标的探测中。为了应对复杂测量条件和多样化被测目标带来的挑战,在确保靶场光电测量设备高精度轨迹测量、高分辨成像能力的同时,对其提出了获取信息多元化、测量波段多样化、多平台机动布站等更多任务需求。我国靶场光电测量设备长足发展,整体性能得到了大幅提升。以中国科学院长春光学精密机械与物理研究所精密仪器与装备研发中心团队近年来在靶场光电测量设备的研制工作为基础,对红外辐射特性测量、结构轻量化设计、光雷一体化测量等多项关键技术的发展历程和现状进行了详细介绍,总结了靶场光电测量设备在多信息获取、探测波段扩展、测量精度提高、设备机动性提升和多平台匹配融合等方面的研究进展,讨论了靶场光电测量设备当前仍然存在的技术难点,并展望了相关技术未来的发展方向。 展开更多
关键词 测量 靶场光电测量 红外辐射特性 结构轻量化 光雷一体化测量
原文传递
Textures, trace element compositions, and sulfur isotopes of pyrite from the Honghai volcanogenic massive sulfide deposit:Implications for ore genesis and mineral exploration
8
作者 zhiyuan sun Xiaohua DENG Franco PIRAJNO 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第4期738-764,共27页
In this paper, we present textures, trace element compositions, and sulfur isotope data for pyrite from the Honghai volcanogenic massive sulfide deposit to place new constraints on the source and evolution of the ore-... In this paper, we present textures, trace element compositions, and sulfur isotope data for pyrite from the Honghai volcanogenic massive sulfide deposit to place new constraints on the source and evolution of the ore-forming fluids and provide insights into the ore genesis with implications for future exploration. The Honghai deposit consists of upper lenticular ores comprising massive sulfides that are underlain by stockwork and disseminated sulfides. The textural and isotopic characteristics of the synsedimentary framboidal pyrite(Syn-Py) indicate its formation by biogenetic processes. Coarse-grained pyrite generations(M-Py1, M-Py2, and M-Py3) from the massive sulfides have high Au, Ag, Cu, Zn, Pb, Sb, and Tl concentrations and low Co, Se, Te, Ti, and Sn concentrations, indicating that they precipitated from metal-rich, low-to intermediate-temperature,oxidizing fluids. The high Te, Ti, and Sn concentrations and high Co/Ni ratios in the massive pyrite(M-Py4) associated with magnetite in the massive sulfide lenses, as well as the high Ti, V, Cr, and Ni concentrations and low Al, Mn, and Zn concentrations in the magnetite, suggest that the coexisting M-Py4 and magnetite precipitated under oxidizing and hightemperature(300℃ to 500℃) conditions. In contrast, pyrite grains from the underlying stockwork and veins(V-Py1, V-Py2, and V-Py3) are characterized by low Au, Ag, Cu, Zn, Pb, Sb, and Tl concentrations coupled with high Co, Se, Te, and Ti concentrations and high Co/Ni ratios, which are interpreted in terms of reducing and high-temperature ore-forming fluids. The large variations in δ^(34)S values from-6.4‰ to +29.9‰ suggest that the ore-forming fluids were derived from magmatic source that were significantly modified by seawater. The spatial variations of trace element assemblages of pyrite from different levels of the main massive orebodies can be used as an indicator for mineral exploration of Cu-Zn ores in the Honghai deposit.Although no significant difference in δ34S values is observed between the upper massive sulfide lenses and lower stockwork/vein zone, the spiky δ34S pattern noted in the massive pyrite can be used as a marker for the main massive orebodies. 展开更多
关键词 PYRITE Trace element compositions Sulfur isotopes Ore-forming fluids Honghai volcanogenic massive sulfide deposit
原文传递
复合菌系降解纤维素过程中微生物群落结构的变化 被引量:18
9
作者 艾士奇 赵一全 +4 位作者 孙志远 高亚梅 晏磊 唐鸿志 王伟东 《生物工程学报》 CAS CSCD 北大核心 2018年第11期1794-1808,共15页
为明确高效纤维素降解复合菌系降解过程中微生物群落结构的变化规律及关键的降解功能菌,利用该复合菌系对滤纸和稻秆进行生物处理,通过底物降解、微生物生长量、发酵液pH的变化情况,选择不同降解时期复合菌系提取的总DNA进行细菌16S rRN... 为明确高效纤维素降解复合菌系降解过程中微生物群落结构的变化规律及关键的降解功能菌,利用该复合菌系对滤纸和稻秆进行生物处理,通过底物降解、微生物生长量、发酵液pH的变化情况,选择不同降解时期复合菌系提取的总DNA进行细菌16S rRNA基因扩增子高通量测序。通过分解特性试验确定在接种后培养第12、72、168 h分别作为降解初期、高峰期、末期。该复合菌系分别主要由1个门、2个纲、2个目、7个科、11个属组成。随着降解的进行,短芽胞杆菌属Brevibacillus、喜热菌属Caloramator的相对丰度逐渐降低;梭菌属Clostridium、芽胞杆菌属Bacillus、地芽胞杆菌属Geobacillus、柯恩氏菌属Cohnella的相对丰度逐渐升高;解脲芽胞杆菌属Ureibacillus、泰氏菌属Tissierella、刺尾鱼菌属Epulopiscium在降解高峰期时相对丰度最高;各时期类芽胞杆菌属Paenibacillus、瘤胃球菌属Ruminococcus的相对丰度无明显变化。上述11个主要菌属均属于厚壁菌门,具有嗜热、耐热、适应广泛pH、降解纤维素或半纤维素的特性。好氧型细菌是降解初期的主要优势功能菌,到中后期厌氧型细菌逐渐增多,并逐步取代好氧型细菌成为降解纤维素的主要细菌。 展开更多
关键词 纤维素 复合菌系 降解 微生物多样性
原文传递
Alkali-metal(Li, Na, and K)-adsorbed MoSi_(2)N_(4) monolayer: an investigation of its outstanding electronic, optical, and photocatalytic properties 被引量:1
10
作者 zhiyuan sun Jing Xu +5 位作者 Nsajigwa Mwankemwa Wenxing Yang Xianwen Wu Zao Yi Shanjun Chen Weibin Zhang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2022年第1期96-104,共9页
Single-layer MoSi_(2)N_(4),a high-quality two-dimensional material,has recently been fabricated by chemical vapor deposition.Motivated by this latest experimental work,herein,we apply first principles calculations to ... Single-layer MoSi_(2)N_(4),a high-quality two-dimensional material,has recently been fabricated by chemical vapor deposition.Motivated by this latest experimental work,herein,we apply first principles calculations to investigate the electronic,optical,and photocatalytic properties of alkali-metal(Li,Na,and K)-adsorbed MoSi_(2)N_(4) monolayer.The electronic structure analysis shows that pristine MoSi_(2)N_(4) monolayer exhibits an indirect bandgap(E_(g)=1.89 eV).By contrast,the bandgaps of one Li-,Na-,and K-adsorbed MoSi_(2)N_(4) monolayer are 1.73 eV,1.61 eV,and 1.75 eV,respectively.Moreover,the work function of MoSi_(2)N_(4) monolayer(4.80 eV)is significantly reduced after the adsorption of alkali metal atoms.The work functions of one Li-,Na-,and K-adsorbed MoSi_(2)N_(4) monolayer are 1.50 eV,1.43 eV,and 2.03 eV,respectively.Then,optical investigations indicate that alkali metal adsorption processes substantially increase the visible light absorption range and coefficient of MoSi_(2)N_(4) monolayer.Furthermore,based on redox potential variations after alkali metals are adsorbed,Li-and Na-adsorbed MoSi_(2)N_(4) monolayers are more suitable for the water splitting photocatalytic process,and the Li-adsorbed case shows the highest potential application for CO_(2) reduction.In conclusion,alkali-metal-adsorbed MoSi_(2)N_(4) monolayer exhibits promising applications as novel optoelectronic devices and photocatalytic materials due to its unique physical and chemical properties. 展开更多
关键词 MoSi_(2)N_(4) FIRST-PRINCIPLES alkali metal adsorbed electronic structure optical properties photocatalysis
原文传递
Percolation-based health management of complex traffic systems 被引量:1
11
作者 Guanwen ZENG zhiyuan sun +4 位作者 Shiyan LIU Xiaoqi CHEN Daqing LI Jianjun WU Ziyou GAO 《Frontiers of Engineering Management》 2021年第4期557-571,共15页
System health management,which aims to ensure the safe and efficient operation of systems by reducing uncertain risks and cascading failures during their lifetime,is proposed for complex transportation systems and oth... System health management,which aims to ensure the safe and efficient operation of systems by reducing uncertain risks and cascading failures during their lifetime,is proposed for complex transportation systems and other critical infrastructures,especially under the background of the New Infrastructure Projects launched in China.Previous studies proposed numerous approaches to evaluate or improve traffic reliability or efficiency.Nevertheless,most existing studies neglected the core failure mechanism(i.e.,spatio-temporal propagation of traffic congestion).In this article,we review existing studies on traffic reliability management and propose a health management framework covering the entire traffic congestion lifetime,from emergence,evolution to dissipation,based on the study of core failure modes with percolation theory.Aiming to be"reliable,invulnerable,resilient,potential,and active",our proposed traffic health management framework includes modeling,evaluation,diagnosis,and improvement.Our proposed framework may shed light on traffic management for megacities and urban agglomerations around the world.This new approach may offer innovative insights for systems science and engineering in fiiture intelligent infrastructure management. 展开更多
关键词 traffic health health management critical infrastructure systems science and engineering
原文传递
A DISCONTINUOUS GALERKIN METHOD BY PATCH RECONSTRUCTION FOR BIHARMONIC PROBLEM
12
作者 Ruo Li Pingbing Ming +2 位作者 zhiyuan sun Fanyi Yang Zhijian Yang 《Journal of Computational Mathematics》 SCIE CSCD 2019年第4期524-540,共17页
We propose a new discontinuous Galerkin method based on the least-squares patch reconstruction for the biharmonic problem. We prove the optimal error estimate of the proposed method. The two-dimensional and three-dime... We propose a new discontinuous Galerkin method based on the least-squares patch reconstruction for the biharmonic problem. We prove the optimal error estimate of the proposed method. The two-dimensional and three-dimensional numerical examples are presented to confirm the accuracy and efficiency of the method with several boundary conditions and several types of polygon meshes and polyhedral meshes. 展开更多
关键词 LEAST-SQUARES PROBLEM Reconstructed basis function DISCONTINUOUS GALERKIN method BIHARMONIC PROBLEM
原文传递
The Discontinuous Galerkin Method by Divergence-Free Patch Reconstruction for Stokes Eigenvalue Problems
13
作者 Di Li zhiyuan sun +1 位作者 Fengru Wang Jerry Zhijian Yang 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE CSCD 2022年第2期484-509,共26页
The discontinuous Galerkin method by divergence-free patch reconstruction is proposed for Stokes eigenvalue problems.It utilizes the mixed finite element framework.The patch reconstruction technique constructs two cat... The discontinuous Galerkin method by divergence-free patch reconstruction is proposed for Stokes eigenvalue problems.It utilizes the mixed finite element framework.The patch reconstruction technique constructs two categories of approximation spaces.Namely,the local divergence-free space is employed to discretize the velocity space,and the pressure space is approximated by standard reconstruction space simultaneously.Benefit from the divergence-free constraint;the identical element patch serves two approximation spaces while using the element pair Pm+1/Pm.The optimal error estimate is derived under the inf-sup condition framework.Numerical examples are carried out to validate the inf-sup test and the theoretical results. 展开更多
关键词 Stokes eigenvalue problems DIVERGENCE-FREE patch reconstruction discontinuous Galerkin mixed finite element
原文传递
Hierarchical Absorbing Interface Conditions for Wave Propagation on Non-Uniform Meshes
14
作者 Shuyang Dai zhiyuan sun +2 位作者 Fengru Wang Jerry Zhijian Yang Cheng Yuan 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE CSCD 2022年第1期251-278,共28页
In this paper,we propose hierarchical absorbing interface conditions to solve the problem of wave propagation in domains with a non-uniform space discretization or grid size inhomogeneity using Pad´e Via Lanczos(... In this paper,we propose hierarchical absorbing interface conditions to solve the problem of wave propagation in domains with a non-uniform space discretization or grid size inhomogeneity using Pad´e Via Lanczos(PVL)method.The proposed interface conditions add an auxiliary variable in the wave system to eliminate the spurious reflection at the interface between regions with different mesh sizes.The auxiliary variable with proper boundary condition can suppress the spurious reflection by cancelling the boundary source term produced by the space inhomogeneity in variational perspective.The new hierarchical interface conditions with the help of PVL implementation can effectively reduce the degree of freedom in solving the wave propagation problem. 展开更多
关键词 Wave equation absorbing interface condition spurious reflection Pad´e via Lanczos
原文传递
Vaccination inhibits TLR2 transcription via suppression of GR nuclear translocation and binding to TLR2 promoter in porcine lung infected with Mycoplasma hyopneumoniae
15
作者 zhiyuan sun Maojun Liu +3 位作者 Xian Li Huafeng Zou Guoqing Shao Ruqian Zhao 《畜牧与兽医》 北大核心 2012年第S1期259-259,共1页
Toll-like receptors(TLRs)and glucocorticoid receptor(GR)act as effectors of innate immune system and neuroendocrine system,respectively.The crosstalk between these two receptors is important to maintain homeostasis du... Toll-like receptors(TLRs)and glucocorticoid receptor(GR)act as effectors of innate immune system and neuroendocrine system,respectively.The crosstalk between these two receptors is important to maintain homeostasis during immune response.It is well known that vaccination can boost adaptive immune responses to specific pathogens.However,it remains elusive whether and 展开更多
关键词 PORCINE MYCOPLASMA translocation crosstalk GLUCOCORTICOID PROMOTER VACCINATION SUPPRESSION homeostasis elusive
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部