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数字经济对中间产品创新价值链的影响研究

科研管理 2024年第8期45卷 32-40,94页

作者：赖俊明何玲辉王文青杭州市农村电商数字化创新发展研究中心浙江杭州310018 浙江育英职业技术学院浙江杭州310018

当前经济循环流动的关键在于供给体系中各产业的关联程度以及创新能力的高低。中间产品作为内循环体系结构中的重要环节,对于降低实体企业的产出损失、促进实体经济的增长具有重要作用。在理论层面,本文对数字经济与中间产品创新之间的... 详细信息

当前经济循环流动的关键在于供给体系中各产业的关联程度以及创新能力的高低。中间产品作为内循环体系结构中的重要环节,对于降低实体企业的产出损失、促进实体经济的增长具有重要作用。在理论层面,本文对数字经济与中间产品创新之间的关系进行了深入探讨。在计量分析方面,本文采用乘数效应理论来建立计量模型,旨在探究数字经济对中国中间产品创新的直接影响和间接影响。研究结果表明:(1)数字经济对中间产品创新具有积极的促进作用;(2)中国中间产品创新在很大程度上依赖于高素质劳动力的培养;(3)虽然国外技术引进在一定程度上可以促进我国中间产品创新,但其效果并不显著;(4)各地区经济实力以及投入占比对中间产品创新具有显著影响;(5)最终产品的生产有利于推动中间产品创新进程。这些发现具有重要的政策意义,提示我们应该加大对数字产业的扶持力度,提高高素质劳动力教育的供给,加强对国内中间产品研发的投入强度,减少对国外技术的过度依赖,深化企业数字化技术应用程度,以充分释放国内消费市场的巨大规模效应,最终完成中国产业的升级换代。

关键词：数字经济中间产品创新价值链产业升级

Buckling morphology of glassy nematic films with staggered director field

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1841-1852页

作者： Shan XIA linghui he College of Civil Engineering Anhui Jianzhu UniversityHefei 230601China Department of Modern Mechanics and State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China

The photo-induced buckling of axially periodic glassy nematic films with alternating stripped director domains is explored by the F¨oppl-von K′arm′an plate theory along with a modified kinetics *** effects of domain widths on the critical light intensity as well as the buckling morphology are examined *** is found that in most cases the buckled film forms regularly aligned dimples and protrusions,but shows large scale bending perpendicular to the periodic axis if the widths of the stripes are nearly the *** addition,change in light intensity is shown to alter the wavenumber of the buckling *** results are expected helpful to the design of shape-shifting structures with glassy nematic films.

关键词： glassy nematic flm buckling morphology staggered director field

Preload-responsive adhesion of microfibre arrays to rough surfaces

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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 155-160页

作者： Yuchen ZHANG linghui he Chinese Academy of Science (CAS) Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei 230026 China

Adhesion of bio-inspired microfibre arrays to a rough surface is studied theoretically. The array consists of vertical elastic rods fixed on a rigid backing layer, and the surface is modeled by rigid steps with a normally distributed height. Analytical expressions are obtained for the adhesion forces in both the approach and retraction processes. It is shown that, with the increasing preload, the pull-off force increases at first and then attains a plateau value. The results agree with the previous experiments and are expected helpful in adhesion control of the array in practical applications.

关键词： fibrillar adhesion rough surface preload pull-off force

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仿生异质结构的非线性力学与优化设计

中国科学：物理学、力学、天文学 2024年第5期54卷 43-73页

作者：王泽文吴开金解丽丽何陵辉倪勇中国科学技术大学工程科学学院近代力学系中国科学院材料力学行为与设计重点实验室合肥230026 中国科学院力学研究所非线性力学国家重点实验室北京100190

轻质高强韧结构设计一直是力学和材料等学科交叉的前沿问题,也是工程应用的不懈追求.生物材料经历数百万年进化,兼具轻质、高强度和高韧性力学性能,成为高性能工程材料设计的模板.然而,生物材料往往具有跨尺度、多层级的复相结构和界面... 详细信息

轻质高强韧结构设计一直是力学和材料等学科交叉的前沿问题,也是工程应用的不懈追求.生物材料经历数百万年进化,兼具轻质、高强度和高韧性力学性能,成为高性能工程材料设计的模板.然而,生物材料往往具有跨尺度、多层级的复相结构和界面特征,会产生非线性、多过程的变形和断裂行为,进而决定强度和韧性等力学性能.如何发展定量的力学模型、阐明生物材料的结构-界面-强韧力学性能间的关系,并为高性能仿生材料制备提供优化设计方案成了近期的研究前沿.本文以极具代表性的生物“砖泥交错结构”和“扭转纤维结构”为例,从力学模型和力学机制方面,首先梳理仿生异质结构代表性单元体(RVE)的非线性力学响应与其结构间的关联;然后讨论含主裂纹仿生异质结构的断裂行为及其与RVE结构间的关联;进一步,基于力学模型和机制,给出优化强度、韧性、抗冲击性和断裂韧性等性能的力学设计方案;最后,提出仿生异质结构非线性力学与优化设计中存在的挑战和未来的发展方向.

关键词：仿生异质结构非线性力学代表性单元体断裂力学优化设计

Damping of Particle-Reinforced Composites Due to Interfacial Sliding

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Acta Mechanica Solida Sinica 2018年第5期31卷 623-634页

作者： linghui he Renhuai Liu CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei 230026 China MOE Key Lab of Disaster and Control in Engineering Institute of Applied Mechanics Jinan University Guangzhou 510632 China

Mechanical damping of composites reinforced by randomly distributed particles due to interfacial sliding is analyzed. The matrix is elastically isotropic, and the particles are assumed rigid and of identical radii. An auxiliary problem is solved at first for the steady-state response of an infinite matrix containing a single inclusion to a harmonic external load. The result is then used to derive the explicit expression of the specific damping capability of the composite by using Mori-Tanaka＇s mean-field method. Numerical results are given and discussed in detail. It is concluded that the overall damping of the composite depends on several factors, including volume fraction of particles, Poisson＇s ratio of matrix and a dimensionless parameter that incorporates the combined effects of particle size, matrix stiffness, interracial viscosity and vibration frequency. The result is expected to be helpful in tailoring the damping performance of particle-reinforced composites.

关键词： Particle-reinforced composite Damping Interracial sliding

Photo-Activated Snap-Through of Nematic Shallow Spherical Shells

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Acta Mechanica Solida Sinica 2022年第2期35卷 239-247页

作者： Yanli Lin linghui he Renhuai Liu MOE Key Lab of Disaster and Control in Engineering Institute of Applied MechanicsJinan UniversityGuangzhou 510632China CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of ChinaHefei 230026China

Photo-responsive nematic polymers can transduce light into mechanical work,but the rate is limited by the quasi-static *** enhance the work output,a strat・egy of exploiting photo-triggered snap-through of glassy nematic shallow spherical shells with hemeotropic director alignment is examined *** criterion for the nonlinear instability is derived analytically by using the modified iteration *** is shown that,for thin shells of small height and large basal radius,snap-through can be caused by an incident light with moderate irradiation *** phenomenon may inspire some new designs of contactless and ultra-fast actuation devices with high-rate output of mechanical work.

关键词： Nematic shell Snap-through Ultra-fast actuation

核心素养视域下体育教学中的表现性评价运用研究

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体育教育学刊 2024年第3期40卷 10-16,F0003页

作者：何凌辉龚坚刘勇西南大学体育学院重庆400715 西南大学教师教育学院重庆400715 两江新区教育发展研究院重庆401122

《义务教育体育与健康课程标准(2022年版)》确立了培养核心素养的育人导向贯穿整个体育教学过程,指向核心素养的体育教学评价改革势在必行。运用案例分析法等研究方法,厘清表现性评价和义务教育体育教学的内在联系。研究认为,应以“为... 详细信息

《义务教育体育与健康课程标准(2022年版)》确立了培养核心素养的育人导向贯穿整个体育教学过程,指向核心素养的体育教学评价改革势在必行。运用案例分析法等研究方法,厘清表现性评价和义务教育体育教学的内在联系。研究认为,应以“为何评”“评什么”“如何评”的思路,创设义务教育体育教学表现性评价,并确立基于核心素养的评价理念,以评价目标具体化、表现性任务具现化、评分规则体系化为创设原则。在实施中,应与体育教学设计同频共振实现“教—学—评”一体化,注重评价的周期性和动态性,达到及时反馈和长期监测目的。同时,收集学生体育活动表现信息并关注学生个体差异,组建评价共同体提高表现性评价效度,以此提高义务教育阶段学生的体育与健康核心素养水平。

关键词：核心素养表现性评价体育教学义务教育义务教育体育课标

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Modeling epidemic spread in transportation networks:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第2期8卷 139-152页

作者： Jian Li Tao Xiang linghui he Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 201804China College of Transportation Engineering Tongji UniversityShanghai 201804China Institute for Urban Risk Management Tongji UniversityShanghai 201804China

The emergence of novel infectious diseases has become a serious global *** transportation networks lead to rapid mobilization in the context of globalization,which is an important factor underlying the rapid spread of infectious *** systems can cause the transmission of viruses during the epidemic period,but they also support the reopening of economies after the *** the mechanism of the impact of mobility on the spread of infectious diseases is thus important,as is establishing the risk model of the spread of infectious diseases in transportation *** this study,the basic structure and application of various epidemic spread models are reviewed,including mathematical models,statistical models,network-based models,and simulation *** advantages and limitations of model applications within transportation systems are analyzed,including dynamic characteristics of epidemic transmission and decision supports for management and ***,research trends and prospects are *** is suggested that there is a need for more in-depth research to examine the mutual feedback mechanism of epidemics and individual behavior,as well as the proposal and evaluation of intervention *** findings in this study can help evaluate disease intervention strategies,provide decision supports for transport policy during the epidemic period,and ameliorate the deficiencies of the existing system.

关键词： Traffic engineering Infectious disease control Epidemic spread models Human mobility Transportation networks

Adhesion hysteresis of a film-terminated fibrillar array

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Science China(Physics,Mechanics & Astronomy) 2012年第6期55卷 1026-1031页

作者： YAN ShunPing he linghui WANG HuiJing Chinese Academy of Sciences Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of ChinaHefei 230026China Department of Computer Application Shenzhen Institute of lnforrnation TechnologyShenzhen 518172China

Motivated by the recent biomimic design of microstructured adhesive surfaces,we study adhesion between a film-terminated fibrillar array and a rigid *** a two-dimensional model and ignoring the deformation of the fibers and the backing layer,we show that the adhesion behavior is dominated by a dimensionless parameter reflecting the global flexibility of the terminal *** particular,if the parameter is larger than 0.4,the adhesion is reversible;otherwise one or more hysteresis loops will appear after an approach-retraction cycle,leading to significant increase in the specific separation *** result is expected to help not only optimal design of the structure,but also other applications such as micro-manipulation in micromechanical systems.

关键词： adhesion hysteresis film-terminated fibrillar array intermolecular force