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浅析《交叉参照(Read-across)方法应用技术指南》
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作者 周奕霏 罗飞亚 +4 位作者 孙磊 杨会英 裴新荣 吴先富 路勇 《香料香精化妆品》 2025年第2期15-22,共8页
交叉参照(read-across)是一种利用已知化学物质的毒理学数据来预测具有相似性的化学物质的相同毒理学终点信息的替代方法。该方法在缺乏系统毒理学数据的情况下能有效减少对动物试验的需求,加快化学物质安全性评估的进程。2024年5月,中... 交叉参照(read-across)是一种利用已知化学物质的毒理学数据来预测具有相似性的化学物质的相同毒理学终点信息的替代方法。该方法在缺乏系统毒理学数据的情况下能有效减少对动物试验的需求,加快化学物质安全性评估的进程。2024年5月,中国食品药品检定研究院发布了《交叉参照(Read-across)方法应用技术指南》。该指南首次明确规范了交叉参照方法用于化妆品安全评估的流程,详细介绍了具体步骤和使用要求。鉴于此,探讨该指南发布的背景与意义、应用准则、核心内容要点和注意事项,旨在强化指南的指导价值,为更多从业人员深入理解、掌握并有效运用该指南提供参考,以促进化妆品安全评估工作的规范性与科学性。 展开更多
关键词 交叉参照 化妆品安全评估 化妆品原料 风险物质
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精密可控常时震源系统(ACROSS)的初步实验 被引量:11
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作者 廖成旺 庄灿涛 梁鸿森 《中国地震》 CSCD 北大核心 2003年第1期89-96,共8页
关键词 精密可控常时震源系统 信号叠加技术 地震波 across震源 信噪比 地震观测
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基于笔语语料库的中国学生介副词across词汇型式使用研究
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作者 王惠霞 《商丘职业技术学院学报》 2019年第2期36-39,62,共5页
介副词across是中国大学生较早习得的词汇之一,同时,across兼有副词和介词功能,用法比较灵活。采用中介语分析方法,通过定量和定性分析,试图描述中国大学生习得介副词across的词汇型式和使用特征及差异,并分析差异产生的原因,为我国英... 介副词across是中国大学生较早习得的词汇之一,同时,across兼有副词和介词功能,用法比较灵活。采用中介语分析方法,通过定量和定性分析,试图描述中国大学生习得介副词across的词汇型式和使用特征及差异,并分析差异产生的原因,为我国英语教学提供借鉴和参考。 展开更多
关键词 中国学生笔语语料库 across 词汇型式 中介语对比研究
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Semiannual velocity variations around the 2008 M_w 7.9 Wenchuan Earthquake fault zone revealed by ambient noise and ACROSS active source data 被引量:4
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作者 Haichao Chen Hongkui Ge Fenglin Niu 《Earthquake Science》 2014年第5期529-540,共12页
We continuously monitor the long-term seismic velocity variation of one of the major ruptured faults of the devastating 2008 Mw7.9 Wenchuan earthquake in China from July 2009 to January 2012,jointly using accurately c... We continuously monitor the long-term seismic velocity variation of one of the major ruptured faults of the devastating 2008 Mw7.9 Wenchuan earthquake in China from July 2009 to January 2012,jointly using accurately controlled routinely operated signal system active source and seismic noise-based monitoring technique.Our measurements show that the temporal velocity change is not homogeneous and highly localized in the damaged fault zone and the adjacent areas.Velocity variations from the active and passive methods are quite consistent,which both are characterized by ±0.2 % seasonal variation,with peak and trough at winter and summer,respectively.The periodic velocity variation within fault zone exhibits remarkably positive correlation with barometric pressure with stress sensitivity in the order of 10-6Pa-1,suggesting that the plausible mechanism might be the crack density variation of the shallow subsurface medium of the damaged fault zone in response to the cyclic barometric pressure loading. 展开更多
关键词 Velocity variation - 2008 WenchuanEarthquake across active source Ambient noise
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A NEW UNSTEADY THREE DIMENSIONAL MODEL FOR MACROMOLECULAR TRANSPORT AND WATER FILTRATION ACROSS THE ARTERIAL WALL 被引量:1
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作者 HUANG Hao(黄浩) +1 位作者 WEN Gong-bi(温功碧) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1155-1172,共18页
A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mit... A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mitosis of endothelial cell of the arterial wall, the macromolecular transport happens surrounding the leaky cells. The arterial wall was divided into four layers: the endothelial layer, the subendothelial intima, the internal elastic lamina and the media for the convenience of research. The time-dependent concentration growth,the effect of the shape of endothelial cell and the effect of physiological parameters were analyzed. The analytical solution of velocity field and pressure field of water flow across the arterial wall were obtained; and concentration distribution of three macromolecules ; LDL,HRP and Albumin, were calculated with numerical simulation method. The new theory predicts, the maximum and distribution areas of time dependent concentration with round shape endothelial cell are both larger than that with ellipse-shape endothelial cell. The model also predicts the concentration growth is much alike that of a two-dimensional model and it shows that the concentration reaches its peak at the leaky junction where atherosclerotic formation frequently occurs and falls down rapidly in a limited area beginning from its earlier time growth to the state when macromolecular transfer approaches steadily. These predictions of the new model are in agreement with the experimental observation for the growth and concentration distribution of LDL and Albumin. 展开更多
关键词 UNSTEADY three-dimensional model flow across the ARTERIAL wall macromolecular TRANSPORTATION ATHEROSCLEROSIS concentration distribution
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Application study of image segmentation methods on pattern recognition in the course of wood across-compression 被引量:1
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作者 曹军 孙丽萍 +1 位作者 张冬妍 姜宇 《Journal of Forestry Research》 CAS CSCD 2000年第1期57-59,共3页
Image segmentation is one of important steps on pattern recognition study in the course of wood across-compression. By comparing and studying processing methods in finding cell space and cell wall, this paper puts for... Image segmentation is one of important steps on pattern recognition study in the course of wood across-compression. By comparing and studying processing methods in finding cell space and cell wall, this paper puts forward some image segmentation methods that are suitable for study of cell images of wood crossgrained compression. The method of spline function fitting was used for linking edges of cell, which perfects the study of pattern recognition in the course of wood across-compression. 展开更多
关键词 Image segmentation Pattern recognition wood across-compression Spline function
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Route Height Connection Across the Sea by Using the Vertical Deflections and Ellipsoidal Height Data 被引量:1
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作者 郭金运 陈永宁 +2 位作者 刘新 钟世霞 麦照秋 《China Ocean Engineering》 SCIE EI CSCD 2013年第1期99-110,共12页
Distance between the main land and island is so long that it is very difficult to precisely connect the height datum across the sea with the traditional method like the trigonometric leveling, or it is very expensive ... Distance between the main land and island is so long that it is very difficult to precisely connect the height datum across the sea with the traditional method like the trigonometric leveling, or it is very expensive and takes long time to implement the height transfer with the geopotential technique. We combine the data of GPS surveying, astro-geodesy and EGM2008 to precisely connect the orthometric height across the sea with the improved astronomical leveling method in the paper. The Qiongzhou Strait is selected as the test area for the height connection over the sea. We precisely determine the geodetic latitudes, longitudes, heights and deflections of the vertical for four points on both sides across the strait. Modeled deflections of the vertical along the height connecting routes over the sea are determined with EGM2008 model based on the geodetic positions and heights of the sea segmentation points from DNSC08MSS model. Differences of the measured and modeled deflections of the vertical are calculated at four points on both sides and linearly change along the route. So the deflections of the vertical along the route over the sea can be improved by the linear interpolation model. The results are also in accord with those of trigonometirc levelings. The practical case shows that we can precisely connect the orthometric height across the Qiongzhou Strait to satisfy the requirement of order 3 leveling network of China. The method is very efficient to precisely connect the height datum across the sea along the route up to 80 km. 展开更多
关键词 height connection across sea deflection of the vertical astro-geodesy orthometric height ellipsoidal height
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The Mathematic Models of the Kalman Filtering for Across-Fault Measurement 被引量:1
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作者 You Lilan,Liu Dajie,Huang Jia’na,Liu Xue and Zhou KechangInstitute of Crustat Dynamics,SSB,Beijing 100085,China Wuhan Technical University of Surveying and Mapping,Wuhan 430070,China National Center for Seismic Data and Inforraanon,SSB,Beijing 100045,China 《Earthquake Research in China》 1994年第3期92-103,共12页
This paper makes a probe into the application of the Kalman filtering method to the data processing of across-fault measurements.On the basis of statistical regression,the mathematic and stochastic models of filtratio... This paper makes a probe into the application of the Kalman filtering method to the data processing of across-fault measurements.On the basis of statistical regression,the mathematic and stochastic models of filtration are established by combining the regression method with Kalman filtering.In the filtering computation,not only the randomness of fault movements but also the time-dependent variation of environmental effects have been taken into consideration.By use of the adaptive filtering method,an estimation of the dynamic noise variance matrix is obtained through iteration.Models for one measuring line(leveling line or baseline),two measuring lines(both leveling lines or both baselines)and four measuring lines(two leveling lines and two baselines)are derived and established systematically.By means of these models,the data of across-fault measurements can be processed dynamically in real-time to provide the filtered values of height difference between benchmarks or baseline length at different time 展开更多
关键词 across-fault MEASUREMENT KALMAN filtration STATE EQUATION OBSERVATIONAL EQUATION Initial STATE Dynamic noise
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Anatomy structure features extraction in the process of large across compressive deformation of wood
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作者 曹军 孙丽萍 +2 位作者 姜濯 李玉峰 周晨松 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第2期121-123,共3页
In this study "the leftest trace algorithm " was used to solve the trace of cells edge better. It also overcame the shortage that use sobel operator and laplace operator to detect the edge of wood cells. Thi... In this study "the leftest trace algorithm " was used to solve the trace of cells edge better. It also overcame the shortage that use sobel operator and laplace operator to detect the edge of wood cells. This realized the rapid extraction of the anatologic shape features in across compression and make possible the wood species could be characterized quantitatively. 展开更多
关键词 Computer vision across compression Image process Detection of objective edges
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Love Across Borders
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《ChinAfrica》 2018年第1期56-57,共2页
The Double Take column looks at a single topic from an African and Chinese perspective. This month we discuss inter-marriage and the impact of different cultural backgrounds.
关键词 Love across Borders Chinese perspective
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A NEW UNSTEADY THREE DIMENSIONAL MODEL FOR MACROMOLECULAR TRANSPORT AND WATER FILTRATION ACROSS THE ARTERIAL WALL
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作者 黄浩 温功碧 《应用数学和力学》 EI CSCD 北大核心 2001年第10期1043-1057,共15页
A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mit... A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mitosis of endothelial cell of the arterial wall, the macromolecular transport happens surrounding the leaky cells. The arterial wall was divided into four layers: the endothelial layer, the subendothelial intima, the internal elastic lamina and the media for the convenience of research. The time-dependent concentration growth, the effect of the shape of endothelial cell and the effect of physiological parameters were analyzed. The analytical solution of velocity field and pressure field of water flow across the arterial wall were obtained; and concentration distribution of three macromolecules; LDL, HRP and Albumin, were calculated with numerical simulation method. The new theory predicts, the maximum and distribution areas of time dependent concentration with round-shape endothelial cell are both larger than that with ellipse-shape endothelial cell. The model also predicts the concentration growth is much alike that of a two-dimensional model and it shows that the concentration reaches its peak at the leaky junction where atherosclerotic formation frequently occurs and falls down rapidly in a limited area beginning from its earlier-time growth to the state when macromolecular transfer approaches steadily. These predictions of the new model are in agreement with the experimental observation for the growth and concentration distribution of LDL and Albumin. 展开更多
关键词 非定常三维模型 大分子传质 动脉粥样硬化 浓度分布 跨血管壁流动
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Analysis of the effects of the heat of sorption on the process of heat transfer in moisture exchange across a membrane 被引量:6
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作者 Teng Hu JingChun Min YaoZu Song 《Science China(Technological Sciences)》 SCIE EI CAS 2008年第12期2120-2127,共8页
A theoretical study has been conducted to investigate the effects of mass transfer on heat transfer in moisture exchange across a membrane and a mathematical model describing the heat transfer process with considerati... A theoretical study has been conducted to investigate the effects of mass transfer on heat transfer in moisture exchange across a membrane and a mathematical model describing the heat transfer process with consideration of the heat of sorption was established. A dimensionless variable, &#936; =JL&#955; /&#948; (T <SUB>10</SUB>&#8722;T <SUB>20</SUB>), which controls the effect of the heat of sorption on the heat transfer in membrane process, was obtained through theoretical analysis, and the effects of &#936; on the heat transfer process were analyzed. Results showed that in the case that the temperature gradient and mass transfer are in the same direction, the effective heat flux changes the direction at &#936;=1. For &#936;【1, the heat transfers from high to low temperature sides through the membrane, and the total thermal resistance increases with increasing the moisture flux across membrane or reducing the temperature difference between the bulk flows on the two sides of membrane. For &#936;】1, the overall effect of the heat and mass transfer is that the effective heat flux points from low to high temperature sides and the total thermal resistance decreases with increasing the mass flux or reducing the temperature difference. In the case that the temperature gradient and mass transfer are in the opposite directions, the existence of the heat of sorption acts to enhance the heat transfer from high to low temperature sides, causing a reduced total thermal resistance, and the greater the mass flux or the smaller the temperature difference, the smaller the total thermal resistance. 展开更多
关键词 MOISTURE EXCHANGE across MEMBRANE HEAT of sorption HEAT transfer PROCESS
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5年生杉木无性系的遗传变异分析及多点联合选择
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作者 林泽忠 罗水金 +3 位作者 张标强 潘隆应 许友承 郑仁华 《森林与环境学报》 北大核心 2026年第1期20-29,共10页
为筛选出适宜福建南平、三明地区的广适型杉木优良无性系,对福建省洋口国有林场、将乐国有林场和沙县官庄国有林场3个试验点的5年生杉木无性系试验林进行了联合测定分析。结果表明,参试无性系林龄5 a时平均树高、胸径及单株立木材积达5.... 为筛选出适宜福建南平、三明地区的广适型杉木优良无性系,对福建省洋口国有林场、将乐国有林场和沙县官庄国有林场3个试验点的5年生杉木无性系试验林进行了联合测定分析。结果表明,参试无性系林龄5 a时平均树高、胸径及单株立木材积达5.69 m、8.81 cm以及0.02241 m^(3)。参试无性系在洋口及官庄试验点的生长表现显著优于将乐试验点。多点联合方差分析结果表明,33个杉木无性系的生长性状在地点效应、无性系效应以及地点与无性系互作效应均达极显著水平(P<0.01)。单一地点的生长性状遗传参数估算结果表明,树高、胸径、单株立木材积的重复力分别为0.646~0.861、0.590~0.754、0.599~0.784,而多点联合方差分析各性状的重复力分别达0.708、0.700及0.713。参试无性系各生长性状之间存在显著的遗传相关和表型相关(P<0.05),基于材积表现,以30%的入选率,在洋口、官庄、将乐试验点各筛选出10个优良无性系,入选无性系平均材积分别为0.03066、0.02871、0.02311 m^(3),较各试验点整体平均值分别高21.71%、19.97%、30.27%,较对照(‘闽杉1号’)分别高57.96%、63.43%、44.70%,平均材积遗传增益分别可达17.02%、15.62%、13.44%。通过联合测定分析,选出57号、35号、31号和80号4个速生、性状稳定且适应范围广的优良无性系,其在3个试验点的平均树高、胸径及单株材积分别可达6.06 m、9.66 cm及0.02809 m^(3),材积平均遗传增益达18.06%。杉木生长性状呈中上程度的遗传控制,存在显著的地点与无性系互作效应。 展开更多
关键词 杉木 无性系 遗传变异 重复力 早期选择 多点联合方差分析
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基于希尔伯特-黄变换的地震触发跨逆断层斜坡失稳机理研究
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作者 韩祥梅 范宣梅 +3 位作者 夏明垚 魏涛 张欣欣 漆芍见 《地震工程学报》 北大核心 2026年第1期228-241,共14页
针对2008年“5·12”汶川地震触发的大规模跨断层岩质斜坡失稳现象,现有研究多关注静态断层或地震瞬时作用,对断层渐进错动过程中能量传递-斜坡响应的动态耦合机制(尤其是倾角效应)缺乏定量认识。通过设计并开展50°和30°... 针对2008年“5·12”汶川地震触发的大规模跨断层岩质斜坡失稳现象,现有研究多关注静态断层或地震瞬时作用,对断层渐进错动过程中能量传递-斜坡响应的动态耦合机制(尤其是倾角效应)缺乏定量认识。通过设计并开展50°和30°跨逆断层斜坡大型振动台模型试验,基于希尔伯特-黄变换(HHT)分析,系统研究地震作用下跨逆断层斜坡的频谱特性和能量演化规律,揭示斜坡累积损伤机制和失稳破坏机理。结果表明:(1)地震能量分布呈现显著上、下盘效应,50°斜坡上、下盘差异相较于30°斜坡更为明显,高倾角断层上盘破坏潜力更大,更易发生快速局部失稳。(2)断层错动诱发斜坡局部高频响应并导致能量集中,加速裂纹扩展;高倾角断层易引发坡体非线性变形并增强动力响应,而低倾角断层则使能量传递更均匀。(3)斜坡裂隙发育受断层错动、剪切和挤压作用控制,从浅表向深部逐步扩展;断层倾角对裂隙发育特征和失稳机制具有重要控制作用。研究成果可为断层活动影响下的地震诱发滑坡风险预警与灾害治理提供新视角和科学依据,具有重要的理论和实际意义。 展开更多
关键词 跨逆断层斜坡 振动台试验 希尔伯特-黄变换 希尔伯特能量 裂纹扩展
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Translocation of chicken heart apocytochrome c and its mutants (C17S, H18D) across mitochondrial membrane
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作者 朱勇 韩学海 杨福愉 《Science China(Life Sciences)》 SCIE CAS 1999年第1期1-7,共7页
The dependence of import of chicken heart apocytochrome c on its transformation to holoform by heme attachment was studied. Results showed that there was no difference in the translocation of apocytochrome c across th... The dependence of import of chicken heart apocytochrome c on its transformation to holoform by heme attachment was studied. Results showed that there was no difference in the translocation of apocytochrome c across the mitochondrial membrane in the presence or absence of hemin + dithionite. Furthermore, two heme unattached mutants (H18D, C17S) were prepared, which could still be accumulated in mitochondria, but their import velocity was obviously reduced. 展开更多
关键词 CHICKEN HEART apocytochrome c MUTANTS H18D C17S TRANSLOCATION across mitochondrial membrane.
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VM migration algorithm for the balance of energy resource across data centers in cloud computing
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作者 Song Da Fu Xiong +4 位作者 Zhou Jingjing Wang Junchang Zhang Lin Deng Song Qiao Lei 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2019年第5期22-32,共11页
Cloud computing makes it possible for users to share computing power.The framework of multiple data centers gains a greater popularity in modern cloud computing.Due to the uncertainty of the requests from users,the lo... Cloud computing makes it possible for users to share computing power.The framework of multiple data centers gains a greater popularity in modern cloud computing.Due to the uncertainty of the requests from users,the loads of center processing unit(CPU)of different data centers differ.High CPU utilization rate of a data center affects the service provided for users,while low CPU utilization rate of a data center causes high energy consumption.Therefore,it is important to balance the CPU resource across data centers in modern cloud computing framework.A virtual machine(VM)migration algorithm was proposed to balance the CPU resource across data centers.The simulation results suggest that the proposed algorithm has a good performance in the balance of CPU resource across data centers and reducing energy consumption. 展开更多
关键词 cloud computing load balancing across data centers virtual machine migration
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An Analytic Equation of State Based on SAFT-CP for Binary Non-Polar Alkane Mixtures Across the Critical Point
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作者 周文来 密建国 +2 位作者 贺刚 于燕梅 陈健 《Tsinghua Science and Technology》 SCIE EI CAS 2003年第6期756-759,共4页
The description using an analytic equation of state of thermodynamic properties near the critical points of fluids and their mixtures remains a challenging problem in the area of chemical engineering. Based on the sta... The description using an analytic equation of state of thermodynamic properties near the critical points of fluids and their mixtures remains a challenging problem in the area of chemical engineering. Based on the statistical associating fluid theory across the critical point (SAFT-CP), an analytic equation of state is established in this work for non-polar mixtures. With two binary parameters, this equation of state can be used to calculate not only vapor-liquid equilibria but also critical properties of binary non-polar alkane mixtures with acceptable deviations. 展开更多
关键词 equation of state the statistical associating fluid theory across the critical point (SAFT-CP) critical point vapor-liquid equilibria
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数字化转型能有效促进企业跨地域创新吗--基于异地子公司创新视角 被引量:7
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作者 周冬华 万贻健 《南开管理评论》 北大核心 2025年第5期16-27,共12页
数字经济是企业创新发展的重要驱动力,数字技术赋能实体经济已成为推动企业高质量发展的重要抓手。本文以2007~2020年中国上市企业为研究样本,利用文本分析法构建数字化转型指标,检验数字化转型对企业跨地域创新的影响。研究发现,数字... 数字经济是企业创新发展的重要驱动力,数字技术赋能实体经济已成为推动企业高质量发展的重要抓手。本文以2007~2020年中国上市企业为研究样本,利用文本分析法构建数字化转型指标,检验数字化转型对企业跨地域创新的影响。研究发现,数字化转型能显著提升异地子公司自主创新水平,推动企业跨地域发展。该结论经过平行趋势和安慰剂检验、替换数字化转型和跨地域创新指标、工具变量法等稳健性检验后依然成立。机制分析发现,数字化转型通过促进知识流动、提高信息透明度来提升企业跨地域创新水平。进一步研究发现,有利的外部环境是提高数字化转型成效的关键;同时,数字化转型有助于突破战略距离,提升欠发达地区子公司的自主创新水平,优化创新结构,实现创新的“增量提质”。此外,企业数字化转型对跨地域创新的促进作用能进一步提升异地子公司运营效率和经营绩效。本研究有助于揭示数字技术赋能实体经济的内在机制,并为推动区域经济平衡发展、实现共同富裕提供重要经验证据。 展开更多
关键词 数字化转型 跨地域创新 知识流动 信息透明度
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中国陆架边缘海碳源汇的强度与控制因素
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作者 宋金明 袁华茂 +8 位作者 李学刚 曲宝晓 钟国荣 邢建伟 马骏 段丽琴 王启栋 戴佳佳 刘珊珊 《海洋学报》 北大核心 2025年第7期1-14,共14页
基于观测和大数据机器学习的研究表明,中国陆架边缘海(渤海、黄海、东海和南海)的年均碳汇强度为(-10.2±4.4)Tg/a。黄海、东海和南海北部全年吸收大气CO_(2),而渤海、南海南部和长江口沿岸向大气释放CO_(2)。东海碳汇最强,平均通量... 基于观测和大数据机器学习的研究表明,中国陆架边缘海(渤海、黄海、东海和南海)的年均碳汇强度为(-10.2±4.4)Tg/a。黄海、东海和南海北部全年吸收大气CO_(2),而渤海、南海南部和长江口沿岸向大气释放CO_(2)。东海碳汇最强,平均通量为(-10.5±4.5)Tg/a,黄海碳汇较小,为(-2.1±0.9)Tg/a。面积最小的渤海碳源为(+0.3±0.1)Tg/a,而面积最大的南海其碳源强度为(+2.0±0.9)Tg/a。从季节上看,冬季我国边缘海碳汇强度最大,为(-45.7±19.7)Tg/a,春季较弱,为(-16.9±7.3)Tg/a。而夏季和秋季我国边缘海整体为碳源,平均分别为(+11.9±5.1)Tg/a和(+9.9±4.3)Tg/a。中国陆架边缘海碳源汇强度平均不确定度为±43.0%(±4.4 Tg/a),比以往用局部海域观测数据导致的平均90.5%的不确定度,基于观测数据机器学习构建格点数据的估算结果不确定度降低了47.5%。海-气界面CO_(2)分压差的差异和由风速引起的CO_(2)交换速率差异是导致我国边缘海海-气界面碳源汇时空变化的关键,究其根本是源于水文动力、陆源输入、浮游生物群落及大洋跨陆架输送等多种因素和过程对我国边缘海海-气碳交换的控制作用。 展开更多
关键词 碳源汇强度 海气界面二氧化碳通量 控制因素 中国陆架边缘海
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税收征管数字化与企业异地投资——基于“金税三期”工程的证据 被引量:2
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作者 崔惠玉 杜淑婷 刘双仪 《财政科学》 2025年第2期77-97,共21页
企业异地投资作为资本跨区域流动的重要表现,对打破市场分割、提高资源配置效率、助推经济高质量发展至关重要。本文基于2009—2021年A股上市公司数据,借助“金税三期”工程实施的契机,构建多期双重差分模型分析税收征管数字化对企业异... 企业异地投资作为资本跨区域流动的重要表现,对打破市场分割、提高资源配置效率、助推经济高质量发展至关重要。本文基于2009—2021年A股上市公司数据,借助“金税三期”工程实施的契机,构建多期双重差分模型分析税收征管数字化对企业异地投资的影响。研究发现,税收征管数字化显著促进了企业异地投资,并且这一政策效应在投资收益率高的企业、竞争更加激烈的行业以及东部地区的企业中更明显。机制分析显示,税收征管数字化通过提高企业纳税遵从、提高企业风险承担能力以及降低企业委托代理成本的方式来促进企业异地投资。拓展分析表明,税收征管数字化的实施也显著促进了企业跨市投资行为,包括企业在同省异市的投资活动;其数字化升级有效提高了企业劳动投资,进一步促进了就业增长。 展开更多
关键词 税收征管数字化 企业异地投资 资本跨区域流动
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