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Numerical Approximation of Stochastic Theta Method for Random Periodic Solution of Stochastic Differential Equations

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 689-701页

作者： Rong wei chuan-zhong CHEN School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China School of Science Hainan UniversityHaikou 570228China

In this paper,we make use of stochastic theta method to study the existence of the numerical approximation of random periodic *** prove that the error between the exact random periodic solution and the approximated on... 详细信息

关键词： Stochastic theta method random periodic solution numerical approximation

Graph deep learning accelerated efficient crystal structure search and feature extraction

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npj Computational Materials 2023年第1期9卷 524-532页

作者： chuan-Nan li Han-Pu liang Xie Zhang Zijing lin Su-Huai wei Department of Physics University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China Beijing Computational Science Research Center Beijing 100193China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China

Structural search and feature extraction are a central subject in modern materials design,the efficiency of which is currently limited,but can be potentially boosted by machine learning(ML).Here,we develop an ML-based prediction-analysis framework,which includes a symmetry-based combinatorial crystal optimization program(SCCOP)and a feature additive attribution model,to significantly reduce computational costs and to extract property-related structural *** method is highly accurate and predictive,and extracts structural features from desired structures to guide materials *** first test SCCOP on 35 typical compounds to demonstrate its *** a case study,we apply our approach to a two-dimensional B-C-N system,which identifies 28 previously undiscovered stable structures out of 82 compositions;our analysis further establishes the structural features that contribute most to energy and *** to conventional approaches,SCCOP is about 10 times faster while maintaining a comparable *** framework is generally applicable to all types of systems for precise and efficient structural search,providing insights into the relationship between ML-extracted structural features and physical properties.

关键词： structural crystal precise

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气固多相催化剂内扩散和反应研究进展

石油炼制与化工 2025年第1期56卷 30-39页

作者：李昕晖李成祥葛蔚沈阳化工大学沈阳110142 中国科学院过程工程研究所介科学与工程全国重点实验室中国科学院大学化学工程学院

化工过程中化学反应通常与传递过程共存,气固多相催化剂一般具有复杂多级孔道结构,其催化性能更是取决于其孔道内反应与扩散过程的耦合。揭示反应和扩散耦合规律,准确获得催化剂颗粒尺度上的反应动力学,对新型催化剂优化设计和制备具有... 详细信息

化工过程中化学反应通常与传递过程共存,气固多相催化剂一般具有复杂多级孔道结构,其催化性能更是取决于其孔道内反应与扩散过程的耦合。揭示反应和扩散耦合规律,准确获得催化剂颗粒尺度上的反应动力学,对新型催化剂优化设计和制备具有重要的科学研究意义和工业应用价值。综述了气固多相催化剂孔道内扩散和反应过程的最新研究进展和反应-扩散耦合的机制,重点介绍反应-扩散耦合模拟研究中的不同模型和方法及其在气固催化反应中的应用。指出将机器学习等人工智能方法和多尺度模拟相结合将会成为研究复杂催化反应体系的一种强大工具。

关键词：反应传递耦合拟颗粒多尺度介尺度分子模拟

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期 32-49页

作者： li-Rong Xiao Chen Chen Shuo Wang Zi-Yin Dai Hideo Kimura Cui Ni chuan-Xin Hou Xue-Qin Sun Si-Jie Guo wei Du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with Ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

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Saliency Detection via Manifold Ranking Based on Robust Foreground

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International Journal of Automation and computing 2021年第1期18卷 73-84页

作者： wei-Ping Ma Wen-Xin li Jin-chuan Sun Peng-Xia Cao Lanzhou Institute of Physics China Academy of Space TechnologyLanzhou 730000China

The graph-based manifold ranking saliency detection only relies on the boundary background to extract foreground seeds,resulting in a poor saliency detection result,so a method that obtains robust foreground for manifold ranking is proposed in this ***,boundary connectivity is used to select the boundary background for manifold ranking to get a preliminary saliency map,and a foreground region is acquired by a binary segmentation of the ***,the feature points of the original image and the filtered image are obtained by using color boosting Harris corners to generate two different convex *** the intersection of these two convex hulls,a final convex hull is ***,the foreground region and the final convex hull are combined to extract robust foreground seeds for manifold ranking and getting final saliency *** results on two public image datasets show that the proposed method gains improved performance compared with some other classic methods in three evaluation indicators:precision-recall curve,F-measure and mean absolute error.

关键词： Saliency detection manifold ranking boundary connectivity convex hull robust foreground

Evaluation on cutting performance of novel PDC cutter for pipe jacking machine

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Underground Space 2024年第1期14卷 34-52页

作者： Long-chuan Deng Yi-Xiang Yuan Xiao-Zhao li Qian-wei Zhuang Chi Zhang Yi-wei Chen School of Earth Sciences and Engineering Nanjing UniversityNanjingJiangsu 210023China Shanghai Tunnel Engineering Co.Ltd. Shanghai 200232China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouJiangsu 221116China School of Mechanics and Engineering Science Shanghai UniversityShanghai 200444China

It is inevitable to cut reinforced concrete(RC)appeared in cross passage of city metro by cutting tools when constructing in densely populated *** previous cutters employed to cut RC are insufficient and easily damaged,so a new polycrystalline diamond compact(PDC)cutter is used to solve this *** on the theoretical analysis of cutting mechanism,both circular and tapered PDC cutters with cutting edge angle of 90and negative front rack angle of 10are used to cut *** peeling and breaking patterns of cutting concrete are proposed,the nodular and grainy chips are the preferred modes in cutting steel *** LS-DYNA is employed to investigate the cutting performance in *** simulation results show that the average and peak cutting forces increase with the growth of penetration depth,cutting speed,and roundness,and subsequently the recommended penetration depth less than 1.2 mm is obtained to cut RC due to the existence of steel ***,the linear cutting platform is adopted to investigate the force ability and damage state of PDC *** is concluded that the cutting force increases abruptly and fluctuates heavily when cutting the coarse *** patterns occurred in both numerical and experimental results are generally ***,the steel bar is pulled out and the PDC cutter is damaged at the penetration depth of 0.8 mm,while a good cut occurs at the penetration depth of 0.3 *** tapered PDC cutter with a relatively low cutting force is prone to be broken compared with circular PDC *** is suggested that the circular PDC cutter at the penetration depth of 0.3 mm should be used to cut RC in practical engineering.

关键词： PDC cutter RC Pipe jacking machine linear cutting tests Damage and wear LS-DYNA

Axiomatisations, alternative formulation anddynamic processes for the maximal self-consistentvalue under multicriteria decision situations

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Journal of Control and Decision 2022年第1期9卷 13-22页

作者： Hui-chuan wei Ai-Tzu li wei-Ni Wang Yu-Hsien liao Department of Adult and Continuing Education National Chung Cheng UniversityMinhsiungTaiwanChina Department of Applied Mathematics National Pingtung UniversityPingtungTaiwanChina

By considering multicriteria decision situations, we adopt excess functions to introduce alternativeformulation and related dynamic processes for the maximal self-consistent value. In orderto present the rationality, ... 详细信息

关键词： Excess function the maximal self-consistent value dynamic process

Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

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Science China life Sciences 2025年第1期 300-302页

作者： Ze-Min lin Mai Xiang Wen-Hui wei Shu-Hui Fan li Chen Jie Wang Xiao-Qian Yang Chun-Hao Yang Shi-Jun He Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug Research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

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Hydrothermal Synthesis and Crystal Structure of a Novel Isophthalate-bridged Copper(II) Polymer with Two-dimensional Network Structure: [Cu_2(phen)(ipt)_2]_(2n)·nH_2O (ipt = isophthalate, phen = 1,10-phenanthroline)

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1411-1415页

作者： CUI Yun-Cheng li Xiu-Mei li chuan-Bi WANG Qing-wei liU Bo li Guo-Feng Jilin Normal University Siping Jilin 136000 China Department of Chemistry Tonghua Teachers college Tonghua Jilin 134002 China

A novel metal-organic coordination polymer [Cu2（phen）（ipt）2]2n-nH2O 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/c with a = 12.338（3）, b = 12.167（3）, c = 18.167（4）A, β= 111.686（14）°, V = 2534.1（10）A^3, C28H18Cu2N2O9, Mr = 653.52, Dc = 1.713 g/cm^3,μ（MoKα） = 1.740 mm^-1, F（000） = 1320, Z = 4, the final R = 0.0443 and wR = 0.0853 for 3543 observed reflections （1 〉 2σ（I））. It exhibits a novel two-dimensional network with tetra-Cu-ipt-as building units.

关键词： isophthalate coordination polymer hydrothermal synthesis crystal structure