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Dynamic Behavior of Phase Synchronization of Chaos

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Chinese Physics Letters 2000年第5期17卷 332-334页

作者： ZHAN Meng HU gang wang xin-gang Department of Physics Beijing Normal UniversityBering 100875 China Center for Advanced Science and Technology(CCAST)(World Laboratory) P.O.Box 8730Beijing 100080

The dynamic nature of phase synchronization between chaotic outputs and injected periodic signals is *** find that the collapse of stroboscopic section from global distribution to local one and the loss of homogeneity of stroboscopic sections in chaotic attractors for different phases are the key features of this kind of phase synchronization,meanwhile the overall structure of chaotic attractor is not affected apparently by the phase synchronization.

关键词： chaotic Chaos attractor

Trigger mechanism of loess-mudstone landslides inferred from ring shear tests and numerical simulation

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Journal of Mountain Science 2021年第9期18卷 2412-2426页

作者： wang xin-gang LIAN Bao-qin Liu Kai Luo Li State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

Whereas loess-mudstone landslides are widely distributed and frequently occurred at the loess Plateau,this type of landslides is hard to detect due to its particularity,and easily generates serious *** clarify the shear characteristics and formation mechanism of loess-mudstone landslides,field investigations,ring shear tests and numerical simulation analyses were performed on the loess specimens collected from the Dingjiagou landslide in Yan’an city,*** test results showed that both the peak strength and residual strength of slip zone soils have a decreasing tendency with moisture content,while the increasing of normal stress caused an increase in the shear *** phenomena indicate that the rise in the moisture content induced by precipitation or the decreasing of normal stress due to excavation activities would result in the weakening of slip zone *** simulations of the evolution process of slope failure using the finite element method were conducted based on the Mohr–Coulomb *** was found that the heavy precipitation played a more important role in the slope instability compared with the *** addition,the field investigation showed that loess soils with well-developed cracks and underlying mudstone soils provide material base for the formation of loess-mudstone ***,the formation mechanism of this type of landslides was divided into three stages,namely,the local deformation stage,the penetration stage,the creeping-sliding *** study may provide a basis for understanding the sliding process of loess-mudstone landslides,as well as guidelines for the prevention and mitigation of loess-mudstone landslides.

关键词： Loess-mudstone landslides Slip zone soil Ring shear tests Numerical simulation Formation mechanism

A modified Hoek-Brown failure criterion considering the damage to reservoir bank slope rocks under water saturation-dehydration circulation

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Journal of Mountain Science 2017年第4期14卷 771-781页

作者： wang xin-gang wang Jia-ding GU Tian-Feng LIAN Bao-qin State Key Laboratory of Continental Dynamics Department of Geology Northwest University School of Geology Engineering and Surveying Chang' an University

After water is impounded in a reservoir, rock mass in the hydro-fluctuation belt of the reservoir bank slope is subject to water saturation- dehydration circulation （WSDC）. To quantify the rate of change of rock mechanical properties, samples from the Longtan dam area were measured with uniaxial compression tests after different numbers （1, 5, 10, 15, and 20） of simulated WSDC cycles. Based on the curves derived from these tests, a modified Hock- Brown failure criterion was proposed, in which a new parameter was introduced to model the cumulative damage to rocks after WSDC. A case of an engineering application was analyzed, and the results showed that the modified Hock-Brown failure criterion is useful. Under similar WSDC-influenced engineering and geological conditions, rock mass strength parameters required for analysis and evaluation of rock slope stability can be estimated according to this modified Hoek-Brown failure criterion.

关键词： Modified Hoek-Brown criterion Reservoir bank slope Hydro-fluctuation belt Water saturation-dehydration circulation Damage

Influence of rheological characteristics on the fluidization catastrophe of tailings flows

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Journal of Mountain Science 2023年第9期20卷 2628-2643页

作者： wang Dao-zheng LIAN Bao-qin wang xin-gang CHEN Xiao-qing wang Jia-ding wang Fei State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China Key Laboratory of Mountain Hazards and Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences(CAS)Chengdu 610041China

Limited by mining technology,mineral exploitation can produce large amounts of *** summer rainfall or seasonal freeze-thaw can lead to physical and chemical modification of tailing material in mountainous areas,resulting in fluidized tailings flow and severe disaster ***,aiming at the problem of tailings fluidization catastrophe,this paper tried to reveal the rheological mechanism of tailings fluidization transformation by combining rheological tests and theoretical *** results show that the yield stress increases with decreasing temperature,and when the density of debris flow(ρ)is more than 1.9 g/cm~3,this behavior becomes more pronounced as the density *** storage modulus decreases by at least two orders of magnitude at the solid-fluid transition under amplitude test *** and loss modulus in the linear viscoelastic range and yield stress have an exponential growth relationship with sediment *** addition,a stress constitutive relation and a new exponential law describing the evolution of yield stress required for solid-liquid transformation were proposed,and the relationship is further strengthened through a comprehensive analysis of existing results,which expands the evaluation application of the rheological characteristics of tailings *** paper provides a new insight into the rheological properties of tailing and how they occur through solid-liquid transition under different environments,which is beneficial to geological hazard prevention and the ecological remediation of the mining area.

关键词： Debris flow Tailing deposits Rheological properties Solid-liquid transition Yield stress

Creep damage properties of sandstone under dry-wet cycles

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Journal of Mountain Science 2020年第12期17卷 3112-3122页

作者： wang xin-gang LIAN Bao-qin wang Jia-ding FENG Wen-kai GU Tian-Feng State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanning 530004China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

Rock creep properties can be used to predict the long-term stability in rock *** reservoir bank slopes,sandstones which are frequently used in the bank slope undergoing longterm effects of dry-wet(DW) cycles due to periodic water inundation and drainage may gradually accumulate creep deformation,resulting in rock structure’s damage or even geological hazards such as *** fully investigate the effect of DW cycles on the creep damage properties of sandstone,triaxial creep tests were conducted on saturated sandstone with different DW cycles by using a triaxial rheometer *** experimental results show that both the instantaneous strain and the stabilized strain increase with the DW *** addition,using the Burgers model,four kinds of functions including an exponentially decreasing function,a linearly decreasing function,a linearly increasing function and an exponentially increasing function were proposed to express the relationships between the shear modulus,viscoelastic parameters of the Burgers model and the deviatoric stress under different DW *** comparative analysis,it is found that the theoretical curves generated using proposed four kinds of functions are in good agreement with the experimental ***,macromorphological and microstructural observations were performed on specimens after various triaxial rheological *** samples with small number of DW cycles,approximately X-shaped fracture surfaces were observed in shear failure zones,whereas several shear fractures including obvious axial and horizontal tensile cracks,and flaws were found for samples with relatively large DW cycles due to long-term propagation and evolution of micro-fissures and ***,as the DW cycles increases,the variation in micro-structure of samples after creep failure was summarized into three stages,namely,a stage with good and dense structure,a stage with pore and fissure propagation,and a stage with extensive in

关键词： Creep damage property Sandstone Drywet cycles Triaxial rheological test Microstructure

A Novel High Nitrogen Nickel-free Coronary Stents System: Evaluation in a Porcine Model

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Biomedical and Environmental Sciences 2014年第4期27卷 289-294页

作者： ZHANG Bin CHEN Ming ZHENG Bo wang xin gang wang Xi Ting FAN Yuan Yuan HUO Yong Department of Cardiology of Peking University First Hospital

Objective To study the safety of the novel high nitrogen nickel-free austenitic stainless steel bare metal stents （BMS） in a recognized porcine coronary model and to select a better grid structure of it. Methods Three types of stents were randomly implanted in different coronary arteries of the same pig： 316L stainless steel BMS （316L-BMS）（n=12）, novel high nitrogen nickel-free stents Grid A （NF-A-BMS）（n=12） and novel high nitrogen nickel-free stents Grid B （NF-B-BMS）（n=12）. In total, eighteen animals underwent successful random placement of 36 oversized stents in the coronary arteries. Coronary angiography was performed after 36 d of stents implantation. Nine animals were respectively sacrificed after 14 d and 36 d for histomorphologic analysis. 〈br〉 Results Quantitative coronary angiography （QCA） showed similar luminal loss （LL） in the three groups：（0.21±0.17） mm for 316L-BMS, （0.16±0.12） mm for NF-A-BMS, （0.24±0.15） mm for NF-B-BMS （P=0.05）. Histomorphomeric analysis after 15 d and 36 d revealed that there was also no significant difference among the three groups in neointimal area （NA） with similar injury scores respectively. High magnification histomorphologic examination showed similar inflammation scores in the three groups, but NF-A-BMS group had poorer endothelialization scores compared with NF-B-BMS group, 2.00±0.63 vs. 2.83±0.41 （P=0.015） at 15 d, which also could be proved by the scanning electron microscope. However, the difference could not been observed at 36 d. Conclusion The novel NF-BMS showed similar safety as 316L-BMS during the short-term study. NF-B-BMS had better endothelialization than NF-A-BMS and this may owe to the specific strut units.

关键词： Austenitic steel Bare metal stent Endothelialization Restenosis Stent thrombosis

Methods of Depth Measurement and Image Fusion Based on Multi-focus Micro-images

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Methods of Depth Measurement and Image Fusion Based on Multi...

LQR Control for Homogeneous Agents with Multi-graph Topology

第25届中国控制与决策会议

作者： Yin Ying-jie wang xin-gang Xu De Zhang Zheng-tao Bai Ming-ran Shi gang Research Center of Precision Sensing and Control Institute of Automation Chinese Academy of Sciences Wuhan Railway Bureau

ISBN: (纸本)9781467355339

When a small object is measured by micro cameras, a sharp image of the whole object is impossible to be obtained because the depth of the object’s surface is different and the distance between different parts of the object’s surface maybe deeper than the depth of field of the micro camera. The camera is focused on different areas of the object’s surface and a series of multi-focus images are taken. The relative depths between the object surface’s different sub-regions will be got by comparing image sharpness evaluation function values of multi-focus images’ same sub-regions and considering the relative position between the camera and the object. Thus the surface depth is obtained. Multi-focus images’ sub-regions with maximum image sharpness evaluation function values are combined into an image. The experimental results verify the effectiveness of the proposed methods.

关键词： depth of field sharpness evaluation function depth measurement multi-focus micro-image image fusion

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自动化学报 2013年第6期39卷 913-919页

作者： ZHANG Dong-Mei OU Lin-Lin MENG Li wang xin-gang College of Science Zhejiang University of Technology Hangzhou310023 China College of Information Engineering ZhejiangUniversity of Technology Hangzhou 310023 China

我们与将军一起考虑一套多代理人系统(质量) 线性时间不变(LTI ) 动力学和性能索引联合系统的行为的一个控制问题。在代理人之间的互联拓扑学与自我环作为一台未受指导的小型旋转式印刷机被建模，在每个系统是一个节点，在每个节点的控... 详细信息

我们与将军一起考虑一套多代理人系统(质量) 线性时间不变(LTI ) 动力学和性能索引联合系统的行为的一个控制问题。在代理人之间的互联拓扑学与自我环作为一台未受指导的小型旋转式印刷机被建模，在每个系统是一个节点，在每个节点的控制行动是它的状态的功能和它的邻居的状态的地方。在这份报纸考虑的线性二次的管理者(LQR ) 控制问题能在反馈获得上由于块对角线限制被认为是一个结构优化问题。它被看那在最小化一个单个代理人系统的和性能的分布式的控制器平等者下面最小化多代理人系统的 LQR 性能限制。一个足够的条件以一套线性矩阵不平等(LMI ) 被介绍完成某些非最优的表演说明。除了使控制设计更适用， LQR 表演区域的观点被介绍并且分析，它被显示关于拉普拉斯算符矩阵的特征值凸。多代理人系统的 LQR 控制然后被变换成一套分系统的 LQR 控制，它作为系数与最小、最大的特征值合并二仅仅不平等限制。数字例子被举说明建议方法。

关键词： LQR控制多代理系统图拓扑线性矩阵不等式线性时不变最大特征值性能指标分布式控制器

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-Tang Liang Yu-gang Ma xin-Li Sheng Qun wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation