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Chimera states of phase oscillator populations with nonlocal higher-order couplings

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Chinese Physics B 2024年第4期33卷 402-407页

作者：伍勇刚余华健郑志刚徐灿 School of Mathematical Sciences Huaqiao UniversityQuanzhou 362021China Institute of Systems Science and College of Information Science and Engineering Huaqiao UniversityXiamen 361021China

The chimera states underlying many realistic dynamical processes have attracted ample attention in the area of dynamical ***, we generalize the Kuramoto model with nonlocal coupling incorporating higher-order interactions encoded with simplicial *** works have shown that higher-order interactions promote coherent ***, we uncover the fact that the introduced higher-order couplings can significantly enhance the emergence of the incoherent ***, we identify that the chimera states arise as a result of multi-attractors in dynamic ***, we review that the increasing higher-order interactions can significantly shape the emergent probability of chimera *** the observed results can be well described in terms of the dimension reduction *** study is a step forward in highlighting the importance of nonlocal higher-order couplings, which might provide control strategies for the occurrence of spatial-temporal patterns in networked systems.

关键词： synchronization complex system coupled oscillators phase transition

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全回转吊舱推进器动态转舵力矩数值预报研究

中国造船 2024年第1期65卷 123-132页

作者：舒永东凌宏杰林勇刚吉青山浙江大学流体动力与机电系统国家重点实验室杭州310027 南京高精船用设备有限公司南京211103 江苏科技大学海洋装备研究院镇江212003

吊舱推进器兼备推进和操纵功能,可在水平面上实现360°全回转。论文基于黏流理论,采用双重滑移网格技术,在指定的吊舱推进器回转与螺旋旋转运动模式下,构建动态转舵力矩数值预报方法。研究表明:与来流速度相比,转舵速度对转舵力矩的影... 详细信息

吊舱推进器兼备推进和操纵功能,可在水平面上实现360°全回转。论文基于黏流理论,采用双重滑移网格技术,在指定的吊舱推进器回转与螺旋旋转运动模式下,构建动态转舵力矩数值预报方法。研究表明:与来流速度相比,转舵速度对转舵力矩的影响很小,当j=0.5时,转舵力矩在260°附近出现最大值,力矩系数为2.384×10^(-3);转舵力矩存在2个响应频率,分别为轴频4.17 Hz和叶频20.8 Hz。研究成果对吊舱推进器转舵系统的设计具有指导意义。

关键词：吊舱推进器全回转水动力数值预报动态转动力矩

Non-uniform,axisymmetric misfit strain:in thin films bonded on plate substrates/substrate systems:the relation between non-uniform film stresses and system curvatures

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Acta Mechanica Sinica 2005年第4期21卷 362-370页

作者： yonggang Huang D. Ngo A. j. Rosakis Department of Mechanical and Industrial Engineering University of Illinois Urbana at Urbana-Champain 1206 West Green Street IL 61801 USA Graduate Aeronautical Laboratory California Institute of TechnologyPasadena CA 91125 USA

Current methodologies used for the inference of thin film stress through curvature measurements are strictly restricted to stress and curvature states which are assumed to remain uniform over the entire film/substrate system. By considering a circular thin film/substrate system subject to non-uniform, but axisymmetric misfit strain distributions in the thin film, we derived relations between the film stresses and the misfit strain, and between the plate system＇s curvatures and the misfit strain. These relations feature a “local” part which involves a direct dependence of the stress or curvature components on the misfit strain at the same point, and a “non-local” part which reflects the effect of misfit strain of other points on the location of scrutiny. Most notably, we also derived relations between the polar components of the film stress and those of system curvatures which allow for the experimental inference of such stresses from full-field curvature measurements in the presence of arbitrary radial non-uniformities. These relations also feature a “non-local” dependence on curvatures making a full-field measurement a necessity. Finally, it is shown that the interfacial shear tractions between the film and the substrate are proportional to the radial gradients of the first curvature invariant and can also be inferred experimentally.

关键词： Non-uniform misfit strain Non-uniform wafer curvatures ,Stress-curvature relations Non-local effects ,Interfacial shears

Growth kinetics of interfacial reaction layer products between cubic boron nitride and Cu-Sn-Ti active filler metal

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journal of Materials Science & Technology 2021年第33期92卷 69-74页

作者： yonggang Fan Cong Wang School of Metallurgy Northeastern UniversityShenyang110819China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

In the present investigation,the growth kinetics of interfacial reaction layer products between cubic boron nitride(CBN) and Cu-Sn-Ti filler metal has been thoroughly *** morphological and compositional features of respective compounds have been demonstrated for a wide brazing temperature ranging from 1153 K to 1223 *** is found that within 30 minutes brazing holding time,the reaction layer growth is largely determined by the population of Ti N via effective Ti diffusion with an activation energy of 223.51 k j/mol,leading to parabolic growth *** is further revealed that TiN grows both in axial and length dimensions,which eventually extends to the forefront and covers the reaction layer.

关键词： Cubic boron nitride Cu-Sn-Ti Interfacial reaction layer Activation energy

西部少数民族地区传统刺绣技艺与艺术特征研究——以羌绣为例

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西部皮革 2024年第12期46卷 72-74页

作者：张玉田永刚西北农林科技大学

为了更好地保护和传承羌绣艺术，文章通过文献研究和田野调查，探究了羌绣的刺绣技艺与艺术特征。羌绣在原材料与刺绣工具选择上有自己的标准，刺绣针法以扎绣、钩绣和挑绣为主，其图案映射出羌族的日常生活、自然景观及社会信仰，如“... 详细信息

为了更好地保护和传承羌绣艺术，文章通过文献研究和田野调查，探究了羌绣的刺绣技艺与艺术特征。羌绣在原材料与刺绣工具选择上有自己的标准，刺绣针法以扎绣、钩绣和挑绣为主，其图案映射出羌族的日常生活、自然景观及社会信仰，如“石榴送子”“藤团牡丹”等，图案色彩则以素绣和彩绣为主。羌绣不仅是一种装饰技艺，更承载着丰富的民族文化和历史价值，深入挖掘并传播其独特技艺与艺术特征，有助于发挥羌绣艺术的独特魅力和文化内涵。

关键词：艺术学羌族刺绣非物质文化遗产美学价值

髋臼覆盖率对股骨头软骨下骨微结构影响的实验研究

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包头医学院学报 2024年第1期40卷 62-70页

作者：班辰昊武永刚包头医学院内蒙古包头014040 巴彦淖尔市医院关节外科

目的:髋臼覆盖率等髋关节参数在一定程度上可以反映股骨头应力分布,通过使用微型计算机断层扫描(Micro-CT)股骨颈骨折(头下型)病人行髋关节置换术后股骨头标本,研究髋臼覆盖率等髋关节参数与股骨头软骨下骨体积分数(BV/TV)的关系,进一... 详细信息

目的:髋臼覆盖率等髋关节参数在一定程度上可以反映股骨头应力分布,通过使用微型计算机断层扫描(Micro-CT)股骨颈骨折(头下型)病人行髋关节置换术后股骨头标本,研究髋臼覆盖率等髋关节参数与股骨头软骨下骨体积分数(BV/TV)的关系,进一步探究局部生物力学改变诱导的软骨下骨微结构改变,为术前计划及生物假体设计提供理论依据。方法:收集因股骨颈骨折行髋关节置换术后股骨头标本30例,对患者行术前常规CT平扫及骨盆正位片拍摄,在骨盆正位片上测量CE角、Sharp角、颈干角、髋臼前倾角等髋关节参数,对患者平扫CT进行三维重建,使用美国国立卫生研究院官方软件Image j测量股骨头髋臼覆盖面积并计算髋臼覆盖率。以股骨头凹为定位标志,分别取张力侧和应力侧软骨下圆柱状松质骨柱。将制作好的组织标本寄送至上海市第六人民医院进行Micro-CT扫描、重建并分析ROI骨体积分数(BV/TV)等参数。对髋关节参数等和软骨下骨微结构参数之间进行单因素分析、多因素线性回归等统计学分析。结果:BMI、髋臼覆盖率、CE角与因变量BV/TV(%)之间以及髋臼覆盖率(%)与CE角之间呈正相关性(P<0.05);髋臼覆盖率及BMI为股骨头张力侧与应力侧软骨下骨体积分数比值(BV/TV%)的独立危险因素(P<0.05)。结论:股骨头软骨下骨体积分数的绝对变化值与髋臼覆盖率呈正相关,股骨头覆盖不足引起的无序关节应力负荷可能导致骨小梁体积明显减少,对生物力学特性和关节软骨有害;BMI过高导致股骨头应力侧局部软骨下骨体积分数增大,可能会导致软骨下骨硬化,进而使软骨失去了应力缓冲,加重软骨损害。

关键词：股骨头髋臼覆盖率骨微结构 Micro-CT

The controlling factors of high suspended sediment concentration in the intertidal flat off the Huanghe River Estuary

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Acta Oceanologica Sinica 2020年第10期39卷 96-106页

作者： Bowen Li yonggang j.a j.Paul Liu j.anfeng Su Xiaolei Liu Mingzheng Wen Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Department of Marine Earth and Atmospheric SciencesNorth Carolina State UniversityRaleighNC 27695USA State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Tianjin Center China Geological SurveyTianjin 300170China

The Huanghe River(Yellow River)is known by its high suspended sediment concentration(SSC)in its river mouth tidal ***,the factors controlling the high SSC over there are not well ***,we conducted 7-d hydrodynamic observations(water depth,wave height,and current velocity)and SSC measurements on the tidal flat off the Huanghe River *** data shows that in most of time,under the calm sea condition,the SSC ranges 0.1–3.5 g/L,and sediment discharge from the river is the main ***,when hydrodynamics are enhanced in a tidal cycle and large-scale erosion occurs on the seafloor,resuspended sediment becomes the main source,and the SSC in the water column reaches 17.3 g/*** find the suspended sediment flux is mainly controlled by the tidal current and Stokes drift,while the wave-induced shear stress could also affect the variation of suspended sediment *** the observation period,when sea under calm-rippled conditions,the current-induced resuspended sediment concentration(RSC)was greater than the wave-induced *** contrast,in smooth-wavelet sea conditions,the wave-induced RSC was greater than the current-induced RSC,for instance,a single wave event was found to cause 11.8 cm seabed erosion within 6 *** study reveals different controlling factors for the high SSC near a river-influenced tidal flat,and helps us get a better understanding of a delta's depositional and erosional mechanisms.

关键词： Huanghe River(Yellow River) sediment re-suspension sediment transport wave current in-situ observation

基于大涡模拟方法的可压缩空化流流场数值模拟分析

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广东化工 2024年第4期51卷 65-68页

作者：张楚谦陈勇刚赵梁中国民用航空飞行学院四川广汉618307 民机火灾科学与安全工程四川省重点实验室四川广汉618307

针对可压缩空化流流场细节特征,对空化的回射流机制与凝结激波机制下的空化云演化过程进行大涡模拟。通过对比文献实验数据验证了可压缩空化流数值模拟方法的可靠性,并分析了空化数σ、CN空化数、St数和压力损失系数K等无量纲参数,发现... 详细信息

针对可压缩空化流流场细节特征,对空化的回射流机制与凝结激波机制下的空化云演化过程进行大涡模拟。通过对比文献实验数据验证了可压缩空化流数值模拟方法的可靠性,并分析了空化数σ、CN空化数、St数和压力损失系数K等无量纲参数,发现数值模拟对空化流压力-速度耦合计算的准确性方面还有待进一步提升。两种空化机制情况下,涡环生长是空化云脱落后耗散过程,涡环溃灭成游离涡是耗散结果;通过大涡模拟实现两种机制下的空化模拟,对比发现回射流机制的空化的无量纲参数偏差较少,凝结激波具有一定偏差;凝结激波的功率谱密度分析发现满足-7/3标度律,回射流满足-5/3标度律。

关键词：文丘里管 LES模型回射流凝结激波空化数压力损失系数 St数功率谱密度分析

LIE-TROTTER FORMULA FOR THE HADAMARD PRODUCT

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Acta Mathematica Scientia 2020年第3期40卷 659-669页

作者： jing WANG yonggang LI Huafei SUN School of Information Beijing Wuzi UniversityBeijing 101149China College of Science Zhengzhou University of AeronauticsZhengzhou 450015China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory on MCAACI Beijing 100081China

Suppose that A and B are two positive-definite matrices,then,the limit of(A^p/2B^pA^p/2)1/p as p tends to 0 can be obtained by the well known Lie-Trotter *** this article,we generalize the usual product of matrices to the Hadamard product denoted as*which is commutative,and obtain the explicit formula of the limit(A^p*B^p)^1/p as p tends to ***,the existence of the limit of(A^p*B^p)^1/p as p tends to+∞is proved.

关键词： Lie-Trotter formula reciprocal Lie-Trotter formula Hadamard product positive-definite matrix