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SUPERCONVERGENCE AND A poSTERIORI ERROR ESTIMATES FOR BOUNDARY CONTROL GOVERNED BY STOKES EQUATIONS

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Journal of Computational Mathematics 2006年第3期24卷 343-356页

作者： Hui-po Liu Ning-ning yan Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

In this paper, the superconvergence results are derived for a class of boundary control problems governed by Stokes equations. We derive superconvergence results for both the control and the state approximation. Base ... 详细信息

关键词： Boundary control Finite element method Superconvergence A posteriori error estimates.

An experimental study of in-plane arch-shaped dampers

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 849-867页

作者： Chien-Liang Lee Yen-po Wang Meng-yan Cai School of Civil Engineering and Architecture Xiamen University of Technology Xiamen 361024 Fujian China Department of Civil Engineering Chiao-Tung University Hsinchu 30010 Chinese Taipei

As an effort to minimize material utilization, seismic steel dampers designed to deform inelastically in an in-plane flexural mode have attracted serious attention recently. This paper presents a new type of metallic yielding damper referred to as the in-plane arch-shaped damper modified from its portal frame-shaped counterpart by replacing the straight beam with a circular arch to minimize the effects of stress concentration and warping, and therefore to avoid premature failure. Component tests of both the portal frame-shaped and arch-shaped in-plane dampers were conducted for comparison. Hysteresis loops obtained from the component tests under cyclic loads indicate substantial improvement on the energydissipative characteristics of the proposed damper. Moreover, seismic performance assessment of the proposed damper was carried out further via shaking table tests of a five-story model frame. Encouraging results have been achieved in terms of acceleration reduction, damping enhancement and peak suppression of the frequency response functions, suggesting the potential of the proposed device to be used in earthquake-resisting systems.

关键词： seismic metallic yielding damper in-plane arch-shaped damper hysteresis loop shaking table test

Numerical investigation of effects of “baffles-deceleration strip” hybrid system on rock avalanches

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Journal of Mountain Science 2019年第2期16卷 414-427页

作者： BI Yu-zhang HE Si-ming DU yan-jun SHAN Jie yan Shuai-xing WANG Dong-po SUN Xin-po Institute of Geotechnical Engineering of Southeast University School of Transportation Southeast University Key Laboratory of Mountain Hazards and Surface Process Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chinese Academy of Sciences Center for Excellence in Tibet Plateau Earth Sciences University of Chinese Academy of Sciences State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology College of civil engineering Sichuan University of Science and Engineering

Arrays of baffles are usually installed in front of protection site to attenuate the flow energy of rock avalanches in mountainous areas. Optimization design is crucial for efficiency promotion in hazard energy dissipation engineering. In this study, a deceleration strip was added in the baffles protection system to optimize the traditional baffles system. The effects of the "baffles-deceleration strip" hybrid protection system was discussed in detail with the nails number and nails angle. This study presents details of numerical experiments using the discreteelement method(DEM). The effect of the optimization of hybrid protection system(nail angle and nail number) were investigated specifically, especially the impact force that avalanches exerted on structures. The results show that the maximum impact forces and kinetic energy of the rock avalanches decreases with the increase of the number and angle of the nail. Moreover, the distance between the toe and the bearing structure(L_m) is also a key factor. The shorter the distance L_m(30 m) is, the higher the maximum impact force are. The longer the distance L_m(70 m) is, the lower the maximum impact force are. Under the same size of the nails, increasing the numbers can enhance the dissipation ability of the hybrid protection system. Meanwhile, increasing itsangle can also enhance the dissipation ability. There are three key ways for nails attenuate rock avalanches:(i) block the fine particles directly;(ii) form the particles bridge between nails and baffles;(iii) dissipate the coarse particles energy directly. The effect of segregation in rock avalanches is crucial for the energy dissipation mechanism, which is a key factor to optimize the traditional baffle system.

关键词： Rock avalanches Baffles Hybrid system Energy dissipation Impact force

Two-Dimensional Transient Temperature Field of Finish Rolling Section in Hot Tandem Rolling

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Journal of Iron and Steel Research International 2004年第4期11卷 29-33页

作者： yanG Li-po PENG yan LIU Hong-min yanshan University

The grain oriented silicon strip was rolled by cross shear rolling (CSR) and then annealed to manufacture non-oriented thin silicon strip of high quality. The recrystallization of rolled grain-oriented silicon steel into non-oriented silicon steel was studied. For this purpose, CSR is better than conventional rolling, and the higher the mismatched speed rate is, the better the properties of the non-oriented thin silicon strip are. The optimum annealing schedule is heating at 1 000 ℃ for 1 h in pure hydrogen atmosphere added with H 2S of 0.001 0 %.

关键词： grain oriented silicon strip non-oriented silicon strip cross shear rolling recrystallization texture

Behavior of traditional concrete dams and three-dimensional printed concrete dams under the debris flow impact

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Journal of Mountain Science 2023年第12期20卷 3703-3717页

作者： MEREE Hani yan Shuai-xing WANG Dong-po BI Yu-zhang State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou 350002China

This study investigated the resilience of traditional concrete dams compared to 3D printed concrete dams(3DPC)when subjected to debris *** types of dams,namely check dams,arch dams,and curve dams,were numerically analyzed using a three-dimensional Coupled Eulerian-Lagrangian(CEL)*** research focused on critical factors such as impact force and viscous energy dissipation to compare dam ***,the study examined the printing and service phases of 3DPC models,determining potential failure modes and analyzing printing *** results demonstrated that 3DPC dams outperformed traditional concrete dams,with filament deposition orientation,perpendicular to the debris flow direction,identified as a pivotal *** percentage and pattern were also found to influence the behavior of 3DPC ***,curved dams exhibited superior performance based on dam *** findings have significant potential for advancing the development of resilient dam structures capable of withstanding debris flow impacts.

关键词： Dam geometry Impact force Printing process Viscous dissipation Coupled Eulerian-Lagrangian Three-dimensional printed concrete

Mean-square composite-rotating consensus of second-order systems with communication noises

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Chinese Physics B 2018年第7期27卷 242-247页

作者： Li-po Mo Shao-yan Guo Yong-guang Yu l School of Science Beijing Technology and Business UniversityBeijing 100048China Department of Mathematics Beijing Jiaotong UniversityBeijing 100044China

We study the mean-square composite-rotating consensus problem of second-order multi-agent systems with communication noises, where all agents rotate around a common center and the center of rotation spins around a fixed point simultaneously. Firstly, a time-varying consensus gain is introduced to attenuate to the effect of communication noises. Secondly, sufficient conditions are obtained for achieving the mean-square composite-rotating consensus. Finally, simulations are provided to demonstrate the effectiveness of the proposed algorithm.

关键词： multi-agent systems mean-square consensus composite-rotating communication noises

Coulomb Interaction in Quantum Dot with a Precessing Magnetic Field

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Communications in Theoretical Physics 2007年第5X期48卷 943-948页

作者： WU Liu-po ZHOU Shi-Ping SONG Hong-yan SHI Yao-Ming Department of Physics Shanghai University Shanghai 200444 China

We study electronic transport through a quantum dot （QD） with a precessing magnetic field. By using the Keldysh nonequilibrium Green function method, formulas of local density of states （LDOS） and conductance of QD are derived self-consistently. It shows that the LDOS and conductance have obvious changes with the Coulomb blockade interaction. The intensity and angle of the magnetic field or temperatures, which reflect the mesoscopic structure of the QD are derived. The superiority of this device is that the QD can be controlled easily by the magnetic field, so it is valuable to apply in generating, manipulating and probing spin state.

关键词： Coulomb interaction quantum dot precessing magnetic field

Underwater Wet Welding for HSLA Steels: Chemical Composition, Defects, Microstructures, and Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1097-1108页

作者： Wen-Bin Gao Dong-po Wang Fang-Jie Cheng Cai-yan Deng Wei Xu Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and Engineering Tianjin University Offshore Oil Engineering Co. Ltd

The effect of water depth on underwater wet welds was investigated by underwater wet shielded metal-arc welding technique. The microstructures, chemical composition, welding defects, and mechanical properties were studied. The contents of alloying elements decrease, while the oxygen content increases with water depth. Within 55 m depth, the carbon monoxide reaction is controlling the oxygen content which will further control the contents of alloying elements. The columnar microstructures in weld metal obtained at shallow water consist of grain boundary ferrite, side-plate ferrite, and acicular ferrite, while those at depth greater than 11 m exhibit more proeutectoid ferrite due to the loss of alloying elements. Mechanical properties are a strong function of depth owing to the increase in oxidation of alloying elements and porosity. Welds obtained within 11 m show preferable strength, ductility, and toughness. The mechanical properties significantly drop from 11 to 25 m because of the increased porosity and oxidation of alloying elements.

关键词： Underwater wet welding Electrode High-strength steel Microstructures Mechanicalproperties

Action of circulating and infiltrating B cells in the immune microenvironment of colorectal cancer by single-cell sequencing analysis

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2683-2696页

作者： Jing-po Zhang Bing-Zheng yan Jie Liu Wei Wang Department of Hepatobiliary and Pancreatic Surgery First Hospital of Hebei Medical UniversityShijiazhuang 050032Hebei ProvinceChina Department of Hepatobiliary Surgery Hunan Provincial People’s HospitalChangsha 410002Hunan ProvinceChina

BACKGROUND The complexity of the immune microenvironment has an impact on the treatment of colorectal cancer(CRC),one of the most prevalent malignancies *** this study,multi-omics and single-cell sequencing techniques were used to investigate the mechanism of action of circulating and infiltrating B cells in *** revealing the heterogeneity and functional differences of B cells in cancer immunity,we aim to deepen our understanding of immune regulation and provide a scientific basis for the development of more effective cancer treatment *** To explore the role of circulating and infiltrating B cell subsets in the immune microenvironment of CRC,explore the potential driving mechanism of B cell development,analyze the interaction between B cells and other immune cells in the immune microenvironment and the functions of communication molecules,and search for possible regulatory pathways to promote the anti-tumor effects of B *** A total of 69 paracancer(normal),tumor and peripheral blood samples were collected from 23 patients with CRC from The Cancer Genome Atlas database(https://***/).After the immune cells were sorted by multicolor flow cytometry,the single cell transcriptome and B cell receptor group library were sequenced using the 10X Genomics platform,and the data were analyzed using bioinformatics tools such as *** differences in the number and function of B cell infiltration between tumor and normal tissue,the interaction between B cell subsets and T cells and myeloid cell subsets,and the transcription factor regulatory network of B cell subsets were explored and *** Compared with normal tissue,the infiltrating number of CD20+B cell subsets in tumor tissue increased *** them,germinal center B cells(GCB)played the most prominent role,with positive clone expansion and heavy chain mutation level increasing,and the trend of differentiation into memory B cells ***,the

关键词： Colorectal cancer Multi-omics analysis Single-cell sequencing analysis Immune microenvironment Infiltrating B cells