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京津冀数字产业发展的时空特征及动态演化

北京社会科学 2025年第1期 15-27页

作者：叶堂林张彦淑首都经济贸易大学城市经济与公共管理学院

基于2013—2022年京津冀地区13个城市的行业数据,采用首位度指数、Zipf位序—规模法则和标准差椭圆法,从产业规模、创新能力和引资能力三个层面,对京津冀地区数字产业发展的时空特征与动态演进趋势进行了深入分析,结果显示:京津冀地区... 详细信息

基于2013—2022年京津冀地区13个城市的行业数据,采用首位度指数、Zipf位序—规模法则和标准差椭圆法,从产业规模、创新能力和引资能力三个层面,对京津冀地区数字产业发展的时空特征与动态演进趋势进行了深入分析,结果显示:京津冀地区数字产业规模差异仍然较大,但规模分布日趋合理;产业规模的空间分布呈显著扩张趋势,但其分布在径向上的不均衡性较为突出。京津冀地区数字产业创新能力不断提升,且地区间差距不断缩小;创新能力呈“先扩张,后集中,再扩张”的空间分布特征,但创新活动主要聚集在北京。京津冀地区数字产业引资能力逐年提高,但分散化的区域集聚特征逐步显现;数字经济服务业的引资能力主要聚集在北京,而数字产品制造业的引资能力则逐步向天津聚集。未来,应从共享共用数字产业创新资源平台、培强做优京津冀地区数字产业集群等方面促进京津冀数字产业发展。

关键词：数字产业标准差椭圆法位序—规模法则京津冀动态演化

新《公司法》下审计委员会的规范阐释与制度构建

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哈尔滨工业大学学报(社会科学版) 2025年第1期27卷 25-36页

作者：叶林钱程中国人民大学法学院北京100872 中国人民大学民商事法律科学研究中心北京100872

新《公司法》虽引入审计委员会制度,但相关规则需要解释和补充。审计委员会被置于强制与自治的交织中,新《公司法》对其机构设置、权力配置等方面均存在强制性要求。审计委员会承接监事会职权,但其职权不仅区别于“审计”,也与我国既有... 详细信息

新《公司法》虽引入审计委员会制度,但相关规则需要解释和补充。审计委员会被置于强制与自治的交织中,新《公司法》对其机构设置、权力配置等方面均存在强制性要求。审计委员会承接监事会职权,但其职权不仅区别于“审计”,也与我国既有实践中的审计委员会的职权存在差别,其在承接监事会职权时需要进行适应性改造,聚焦于财务监督职能。针对审计委员会的人员组成,目前区分公司类型的做法较为可取,但未来还需要在灵活性和任意性等方面设计特殊规则;而审计委员会的选任方式可以采取“董事会提名成员、股东会确认”的方式。最后,审计委员会原则上以集体会议方式行使权力,因而需要对议事规则进行补充;审计委员会成员应当享有收集信息的个人权力,实现监督效率的提高。

关键词：新《公司法》审计委员会监事会监督权人员组成议事规则

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Path-Dependent Progressive Failure Analysis for 3D-Printed Continuous Carbon Fibre Reinforced Composites

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 84-93页

作者： Yuan Chen lin ye School of System Design and Intelligent Manufacturing(SDIM) Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Intelligent Manufacturing for Continuous Carbon Fibre Reinforced Composites Southern University of Science and TechnologyShenzhen 518055China

In order to predict the damage behaviours of 3D-printed continuous carbon fibre(CCF)reinforced composites,when additional short carbon fibre(SCF)composite components are employed for continuous printing or special functionality,a novel path-dependent progressive failure(PDPF)numerical approach is ***,a progressive failure model using Hashin failure criteria with continuum damage mechanics to account for the damage initiation and evaluation of 3D-printed CCF reinforced polyamide(PA)composites is developed,based on actual fibre placement trajectories with physical measurements of 3D-printed CCF/PA ***,an elastic-plastic model is employed to predict the plastic damage behaviours of SCF/PA ***,the accuracy of the PDPF model was validated so as to study 3D-printed CCF/PA composites with either negative Poisson's ratio or high *** results demonstrate that the proposed PDPF model can achieve higher prediction accuracies in mechanical properties of these 3D-printed CCF/PA *** analyses show that the stress distribution is generally aggregated in the CCF areas along the fibre placement paths,and the shear damage and matrix tensile/compressive damage are the key damage *** study provides a new approach with valuable information for characterising complex 3D-printed continuous fibre-matrix composites with variable mechanical properties and multiple constituents.

关键词： 3D printing Continuous carbon fibre Modelling Energy absorption Negative Poisson's ratio

Investigations of Water Flow Behaviors Induced by Local Temperature Variations through a Single Rough Fracture for the Enhanced Geothermal Systems

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Journal of Thermal Science 2024年第3期33卷 1055-1064页

作者： LI Jiawei ye lin Department of Energy and Power Engineering Tsinghua UniversityBeijing100084China School of Power and Energy Northwestern Polytechnical UniversityXi’an710072China

In recent years,Enhanced Geothermal System(EGS)technologies have been applied to the geothermal resources production in the Hot Dry Rock(HDR).The core of EGS technologies is to adopt hydraulic fracturing in the reservoir to create a connected network of discrete fractures with the consideration of water as a working fluid for hydraulic fracturing and heat *** paper investigates the characteristics of water flow behaviors through a single rough fracture under different temperature and pressure conditions.A single fracture model with rough fracture surfaces is constructed and then characterized,and influences of the anisotropic factor on the average tortuosity and frictional resistance coefficient of water flow through a single fracture with rough surfaces have been compared and *** consideration of other impacting factors(temperature,pressure,fracture roughness),the impact of mass flow rate has also been *** simulation results present that changes of average tortuosity for water flow through a single rough facture are mainly affected by *** can be observed that higher temperature leads to larger average tortuosity but the frictional resistance coefficient shows an opposite *** for pressure conditions,it is found that effects of pressure on average tortuosity and frictional resistance coefficient is very small,which can be neglected under high pressure ***,the average tortuosity shows a progressively linear relationship with the mass flow *** the contrary,the frictional resistance coefficient has a negative relationship with the mass flow *** is revealed that when the mass flow rate reaches a critical point,the influences of temperature on the frictional resistance coefficient will be *** of single rough fractures with different anisotropic factors show that values of average tortuosity and frictional resistance coefficient have positive relationships with the increase

关键词： single rough fracture tortuosity frictional resistance enhanced geothermal system

我国农产品流通效率时空演变、地区差异与收敛性

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经济问题 2025年第1期 100-112页

作者：高国生叶林祥支海兵南京财经大学粮食和物资学院江苏南京210003 南京审计大学金审学院管理学院江苏南京210023 南京财经大学经济学院江苏南京210003

农产品流通效率事关我国粮食安全和全国统一大市场的建成。运用熵值法测度了2011—2022年我国31个省级行政区的农产品流通效率,并使用Moran’s I、Kernel核密度估计、Markov链、Dagum基尼系数和β收敛模型分别分析了我国农产品流通效率... 详细信息

农产品流通效率事关我国粮食安全和全国统一大市场的建成。运用熵值法测度了2011—2022年我国31个省级行政区的农产品流通效率,并使用Moran’s I、Kernel核密度估计、Markov链、Dagum基尼系数和β收敛模型分别分析了我国农产品流通效率的时空演变、地区差异与收敛性情况。结果显示:研究期内我国农产品流通效率存在显著正向空间相关性,“高—高”集聚和“低—低”集聚特征明显;核密度曲线宽度变大呈现右拖尾和高度差明显的双峰形态,表明农产品流通效率逐渐提升,地区内部存在极化趋势;相邻省区市空间滞后水平对本省区市农产品流通效率维持原有状态或向更高水平发展均有较大影响;地区间差异是造成农产品流通效率总体差异显著的主要原因;农产品流通效率存在显著绝对β收敛和条件β收敛。据此,对如何提高农产品流通效率和缩小地区间差距提出了相关政策建议。

关键词：农产品流通效率时空演变空间分布地区差异

面向中国式现代化的超大城市治理:政治逻辑、战略定位与发展路径

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公共治理研究 2025年第1期37卷 45-57页

作者：叶林梅畅中山大学政治与公共事务管理学院广东广州510275

超大城市是中国式现代化的核心引擎和关键载体,其治理效果直接关乎中国式现代化的推进成效。我国超大城市治理的政治逻辑是中国式现代化,时代背景是“两个大局”,政治内涵是中国特色社会主义,价值追求是人民城市,实践要求是以系统思维... 详细信息

超大城市是中国式现代化的核心引擎和关键载体,其治理效果直接关乎中国式现代化的推进成效。我国超大城市治理的政治逻辑是中国式现代化,时代背景是“两个大局”,政治内涵是中国特色社会主义,价值追求是人民城市,实践要求是以系统思维统筹现代化过程。在这一逻辑下,超大城市治理通过链接国家与社会成为国家治理的战略之基,通过经济规模性成为现代化质量变革的动力之源,通过示范引领成为共生发展的突破之窗。面对时代重任,超大城市应加快转变治理方式,分别以党建引领、精细化治理、适应性治理实现超大城市治理主体重塑、治理机制重构、治理目标优化,为中国式现代化履行“大国大城”“强国强城”的历史使命。

关键词：中国式现代化超大城市治理人民城市

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Functionalized interleaf technology in carbon-fibre-reinforced composites for aircraft applications

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National Science Review 2014年第1期1卷 7-8页

作者： lin ye School of Aerospace Mechanical and Mechatronic Engineering and Centre for Advanced Materials Technology University of Sydney

At the recent 19th International Conference of Composite Materials(ICCM-19),in Montreal,Professor Xiaosu Yi from the Beijing Institute of Aeronautical Materials,Aviation Industry Corporation of China,gave a plenary lecture on‘How to Make the Structural Composites Multi-functional’.His lecture highlighted the recent developments from his research team in functionalized interleaf technology(FIT).heir work

关键词： Ag

Investigation of the overconsolidation and structural behavior of Shanghai clays by element testing and constitutive modeling

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Underground Space 2016年第1期1卷 62-77页

作者： Guan-lin ye Bin ye Department of Civil Engineering and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

The mechanical properties and constitutive modeling of Shanghai clays are very important for numerical analysis on geotechnical engineering in Shanghai,where continuous layers of soft clays run 30-40 m *** clays are divided into 5 major layers.A series of laboratory tests are carried out to investigate their mechanical *** top and bottom layers are overconsolidated hard clays,and the middle layers are normally consolidated or lightly overconsolidated sensitive marine clays.A constitutive model,which can describe the overconsolidation and structure of soils using only 8 parameters,is modified to simulate the test results.A rational procedure to determine the values of the material parameters and initial conditions is also *** model is able to effectively reproduce both one-dimensional(1D)consolidation and drained/undrained triaxial test results of Shanghai clays,with one set of parameters for each *** element testing and constitutive modeling,two findings are ***,the decay rates of overconsolidation are smaller in overconsolidated layers than in normally consolidated ***,the natural microstructure of layer 4 is relatively stable,that is,a large degree of structure is still maintained in the specimen even after 1D consolidation and drained triaxial *** modified model and obtained parameter values can be used for numerical analysis of geotechnical projects in Shanghai.

关键词： Shanghai clays Laboratory tests Constitutive model Overconsolidation Structure

基于特征模态分解及多尺度模糊散布熵的滚动轴承故障诊断

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科学技术与工程 2025年第1期25卷 176-185页

作者：梁翔宇胡业林马向阳宋晓安徽理工大学电气与信息工程学院淮南232000

针对复杂环境下的滚动轴承故障信息有效提取与辨识问题,提出一种基于特征模态分解(feature mode decomposition,FMD)及多尺度模糊散布熵(multiscale fuzzy dispersion entropy,MFDE)和斑马优化算法(zebra optimization algorithm,ZOA)优化支持向量机的滚动轴承故障诊断方法。为了解决FMD中关键参数不具有自适应性这一问题,以最小包络熵作为目标函数,采用白鲸优化算法(beluga whale optimization,BWO)优化FMD寻找最优参数组合,实现对故障信号的最优分解;引入多尺度模糊散布熵构建分解后不同模态下的特征向量;最后,将特征向量输入支持向量机中进行训练和识别,通过公开数据集和自制实验平台数据集验证了提出方法的有效性。

关键词：特征模态分解多尺度模糊散布熵支持向量机滚动轴承故障诊断