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Seismic wave input method for three-dimensional soil-structure dynamic interaction analysis based on the substructure of artificial boundaries 被引量:18
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作者 Liu Jingbo Tan Hui +2 位作者 Bao Xin Wang Dongyang Li Shutao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期747-758,共12页
The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident... The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident wave into equivalent loads on the cutoff boundaries. The wave method has high precision, but the implementation is complicated, especially for three-dimensional models. By deducing another form of equivalent input seismic loads in the fi nite element model, a new seismic wave input method is proposed. In the new method, by imposing the displacements of the free wave fi eld on the nodes of the substructure composed of elements that contain artifi cial boundaries, the equivalent input seismic loads are obtained through dynamic analysis of the substructure. Subsequently, the equivalent input seismic loads are imposed on the artifi cial boundary nodes to complete the seismic wave input and perform seismic analysis of the soil-structure dynamic interaction model. Compared with the wave method, the new method is simplifi ed by avoiding the complex processes of calculating the equivalent input seismic loads. The validity of the new method is verifi ed by the dynamic analysis numerical examples of the homogeneous and layered half space under vertical and oblique incident seismic waves. 展开更多
关键词 soil-structure dynamic interaction SEISMIC WAVE input WAVE method EQUIVALENT input SEISMIC loads SUBSTRUCTURE of artifi cial boundaries
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Study on Pinyin-Stroke Coding Input Method For Chinese Characters
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作者 CHEN Qin-wu LIU Rui-shun LIU Xiu-feng 《微计算机信息》 2010年第36期255-257,279,共4页
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A useful method for determination of optimal fiber input power in spontaneous Brillouin-scattering-based sensing system 被引量:2
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作者 李永倩 李晓娟 +1 位作者 范寒柏 张立欣 《Optoelectronics Letters》 EI 2018年第1期53-56,共4页
A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne... A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne detection system is constructed for measuring the Brillouin scattering spectra with different fiber input powers. The Brillouin spectrum width and system SNR can be simultaneously measured from these spectra, and the optimal fiber input power can be obtained from such information. In the experiment, for 48.8-km-long standard single-mode fiber(SSMF), the optimal fiber input power values are all approximately 0 dBm obtained by the maximum SNR position for different local oscillator power values and average times. 展开更多
关键词 SNR A useful method for determination of optimal fiber input power in spontaneous Brillouin-scattering-based sensing system
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Application of Reciting Methods on Secondary School Oral English Learning — based on Krashen's Input Hypothesis
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作者 严佳佳 《海外英语》 2015年第20期228-230,共3页
It has been found that a large amount of students are not able to communicate fluently and lack self-confidence. Therefore, they lost interest in English. This paper first introduces Stephen Krashen's Input Hypoth... It has been found that a large amount of students are not able to communicate fluently and lack self-confidence. Therefore, they lost interest in English. This paper first introduces Stephen Krashen's Input Hypothesis. Through analyzing the influencing factors of oral English learning and the significance of reciting methods, the article explored the concrete reciting methods. I hope it will shed some light on the English teaching and learning practice. 展开更多
关键词 SECONDARY SCHOOL students ORAL English input HYPOTHESIS reciting methodS
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Development of service industry in Shandong province based on input-output method
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作者 ZHOU Jiang-tao 《Ecological Economy》 2018年第1期28-36,共9页
Based on 2012 input-output table of Shandong province and the official statistics, this article uses the input-output analysis method to build the input-output table. On the basis of the development of service industr... Based on 2012 input-output table of Shandong province and the official statistics, this article uses the input-output analysis method to build the input-output table. On the basis of the development of service industry in Shandong province's ability, we make a theoretical analysis framework of a comprehensive in-depth analysis on pull employment, creatively will cost tax rate, fully and completely labor capital and the combination of both the industry development space. So that the industry's ability to pull the employment can be considered, and to realize rapid and sustained development of service industry in Shandong province. 展开更多
关键词 input-output method service industry EMPLOYMENT formats
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A METHOD FOR CALCULATING TRANSIENT FUNCTIONS OF EQUIVALENT DETERMINISTIC INPUT
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《Chinese Journal of Aeronautics》 SCIE EI CAS 1988年第2期98-104,共7页
In the present paper the analytical formulas for calculating the equivalent deterministic transients for multivariable cross correlated random processes are developed.The formulas permit the determination of the Root-... In the present paper the analytical formulas for calculating the equivalent deterministic transients for multivariable cross correlated random processes are developed.The formulas permit the determination of the Root-mean-square of the responses of a linear time-invariant system to stationary multiple random inputs in the time domain.The method is applicable in the study of flight of airplanes in atmospheric turbulence and is also useful for general engineering applications of stochastc processes control. 展开更多
关键词 A method FOR CALCULATING TRANSIENT FUNCTIONS OF EQUIVALENT DETERMINISTIC input
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中国绿色就业规模测算及其效应分析
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作者 徐强 苗彤 《统计与信息论坛》 北大核心 2026年第1期1-18,共18页
绿色经济是重要的国家发展战略,当前中国正步入绿色转型的关键时期。为洞悉绿色转型对中国就业市场的影响,采用投入产出法和结构分解法测算2012—2020年中国绿色就业规模,量化评估中国绿色产业的就业吸纳能力,并系统性剖析劳动生产率、... 绿色经济是重要的国家发展战略,当前中国正步入绿色转型的关键时期。为洞悉绿色转型对中国就业市场的影响,采用投入产出法和结构分解法测算2012—2020年中国绿色就业规模,量化评估中国绿色产业的就业吸纳能力,并系统性剖析劳动生产率、产业结构调整以及最终需求规模波动对绿色就业规模的影响。测算结果表明,2012—2020年绿色产业增加值持续稳定增长,绿色就业规模呈先减后增趋势,绿色就业规模占历年就业总数的比重基本维持在4%~5%之间,与国际既有研究的测算结果大致处于同一水平。从就业效应来看,绿色产业的就业创造效应超过了替代效益,当前绿色产业正处于就业吸纳阶段,推动就业规模有效扩大。从就业规模影响因素来看,劳动生产率、产业结构调整以及最终需求规模波动对不同类型产业就业的影响存在明显异质性,服务业在绿色转型过程中为稳定就业市场发挥了重要作用。从拓展性研究来看,绿色转型背景下绿色产业的劳动力需求向高技能和低技能劳动者倾斜,呈现技能偏态性、劳动力“极化”等特征。通过以上分析,提出合理选择绿色转型模式、完善劳动力市场服务体系、完善职业培训体系等政策建议,为政府相关部门制定产业转型策略提供参考,为化解绿色转型过程中劳动力市场的矛盾和冲突提供经验支持。 展开更多
关键词 绿色经济 绿色就业 投入产出法 结构分解法 就业效应
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Design of space-centered interaction using invisible and intangible spatial inputs
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作者 David Jean Kwangjin Hong Keechul Jung 《Journal of Measurement Science and Instrumentation》 CAS 2012年第2期137-145,共9页
In this paper,we investigate methodologies to improve direct-touch interaction on invisible and intangible spatial input.We firstly discuss about the motive of looking for a new input method for whole body interaction... In this paper,we investigate methodologies to improve direct-touch interaction on invisible and intangible spatial input.We firstly discuss about the motive of looking for a new input method for whole body interaction and how it can be meaningful.We also describe the role that can play spatial interaction to improve the freedom of interaction for a user.We propose a method of spatial centered interaction using invisible and intangible spatial inputs.However,given their lack of tactile feedback and visual representation,direct touch interaction on such input can be confused.In order to make a step toward understanding causes and solutions for such phenomena,we made 2 user experiments.In the first one,we test 5 setups of helper that provide information of the location of the input by constraining the dimension it is located at.The results show that using marker on the ground and a relationship with the height of the user’s body improve significantly the locative task.In the second experiment,we create a dancing game using invisible and intangible spatial inputs and we stress the results obtained in the first experiment within this cognitively demanding context.Results show that the same setup of helper is still providing very good results in that context. 展开更多
关键词 human-computer interaction(HCI) spatial centered interaction whole body interaction input method
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Attitude Control Considering Variable Input Saturation Limit for a Spacecraft Equipped with Flywheels 被引量:7
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作者 TIAN Lin XU Shijie 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2012年第3期437-445,共9页
A new attitude controller is proposed for spacecraft whose actuator has variable input saturation limit. There are three identical flywheels orthogonally mounted on board. Each rotor is driven by a brushless DC motor ... A new attitude controller is proposed for spacecraft whose actuator has variable input saturation limit. There are three identical flywheels orthogonally mounted on board. Each rotor is driven by a brushless DC motor (BLDCM). Models of spacecraft attitude dynamics and flywheel rotor driving motor electromechanics are discussed in detail. The controller design is similar to saturation limit linear assignment. An auxiliary parameter and a boundary coefficient are imported into the controller to guaran- tee system stability and improve control performance. A time-varying and state-dependent flywheel output torque saturation limit model is established. Stability of the closed-loop control system and asymptotic convergence of system states are proved via Lyapunov methods and LaSalle invariance principle. Boundedness of the auxiliary parameter ensures that the control objective can be achieved, while the boundary parameter's value makes a balance between system control performance and flywheel utilization efficiency. Compared with existing controllers, the newly developed controller with variable torque saturation limit can bring smoother control and faster system response. Numerical simulations validate the effectiveness of the controller. 展开更多
关键词 spacecraft attitude control variable input saturation limit Lyapunov methods flywheels brushless DC motor
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Carbon price impacts on sector cost:based on an input-output model of Beijing
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作者 Yijing Zhang Alun Gu Xiusheng Zhao 《Chinese Journal of Population,Resources and Environment》 2014年第3期239-246,共8页
Under the pressure of sustained growth in energy consumption in China,the implementation of a carbon pricing mechanism is an effective economic policy measure for promoting emission reduction,as well as a hotspot of r... Under the pressure of sustained growth in energy consumption in China,the implementation of a carbon pricing mechanism is an effective economic policy measure for promoting emission reduction,as well as a hotspot of research among scholars and policy makers.In this paper,the effects of carbon prices on Beijing's economy are analyzed using input-output tables.The carbon price costs are levied in accordance with the products'embodied carbon emission.By calculation,given the carbon price rate of 10 RMB/t-CO_2,the total carbon costs of Beijing account for approximately 0.22-0.40%of its gross revenue the same year.Among all industries,construction bears the largest carbon cost Among export sectors,the coal mining and washing industry has much higher export carbon price intensity than other industries.Apart from traditional energy-intensive industries,tertiary industry,which accounts for more than 70%of Beijing's economy,also bears a major carbon cost because of its large economic size.However,from 2007 to 2010,adjustment of the investment structure has reduced the emission intensity in investment sectors,contributing to the reduction of overall emissions and carbon price intensity. 展开更多
关键词 carbon PRICING input-OUTPUT method BEIJING EMBODIED emissions
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On Stability Delay Bounds of Simple Input-delayed Linear and Non-linear Systems: Computational Results 被引量:1
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作者 Elbrous M. Jafarov 《International Journal of Automation and computing》 EI CSCD 2013年第4期327-334,共8页
This paper deals with the problem of delay size stability analysis of single input-delayed linear and nonlinear systems. Conventional reduction, reduction linked by sliding mode, and linear memoryless control approach... This paper deals with the problem of delay size stability analysis of single input-delayed linear and nonlinear systems. Conventional reduction, reduction linked by sliding mode, and linear memoryless control approaches are used for simple input-delayed systems to obtain the stability conditions. Several first order examples are investigated systematically to demonstrate the capabilities and limitations of the advanced stability analysis techniques including Lyapunov-Krasovskii functionals, Newton-Leibniz formula, and a newly addressed Lagrange mean value theorem. Numerical comparative results show the usefulness and effectiveness of the advanced delay size analysis techniques proposed in this paper. 展开更多
关键词 input-delayed systems reduction method Lagrange mean value theorem sliding mode control Lyapunov-Krasovskii functional.
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Dynamical Analysis of a Stochastic Predator-Prey System with Lévy Noise and Impulsive Toxicant Input
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作者 Xiaowan She Yuanfu Shao Taolin Zhang 《Journal of Applied Mathematics and Physics》 2020年第9期1999-2019,共21页
This paper established a modified Leslie-Gower and Holling-type IV stochastic predator-prey model with Lévy noise and impulsive toxicant input. We study the stability in distribution of solutions by inequality te... This paper established a modified Leslie-Gower and Holling-type IV stochastic predator-prey model with Lévy noise and impulsive toxicant input. We study the stability in distribution of solutions by inequality techniques and ergodic method. By comparison method and It<span style="white-space:nowrap;">&#244;</span>’s formula, we obtain the sufficient conditions for the survival of each species. Some numerical simulations are introduced to show the theoretical results. 展开更多
关键词 Lévy Noise Impulsive Toxicant input Comparison method Extinction and Persistence
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Finite element analysis of welding residual stress of aero engine blisk by controlling heat input
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作者 张学秋 杨建国 +3 位作者 陈绪辉 方洪渊 曲伸 王立诚 《China Welding》 EI CAS 2009年第2期70-74,共5页
In order to improve aero engine performance, it is necessary to reduce the welding residual stress of aero engine blisk. In this paper, finite element method was employed to simulate electron beam welding process of b... In order to improve aero engine performance, it is necessary to reduce the welding residual stress of aero engine blisk. In this paper, finite element method was employed to simulate electron beam welding process of blisk, in accordance with the deducing formula( p = kh ) , the heat input is changed with the weld depth to control welding residual stress of blisk. The calculation results show that welding residual stress of blisk can be controlled effectively by reducing the heat input on the conditions of meeting the demand of weld penetration and guaranteeing the welding quality, a new theoretical method and some numerical data are provided for controlling welding residual stress of blisk. 展开更多
关键词 heat input BLISK finite element method residual stress
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Case Study of a Chinese Girl's English Learning Methods in the American Elementary School
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作者 杨丽 《海外英语》 2017年第6期239-240,共2页
The goal of this research is to explore a more successful method for Mainland Chinese students to learn English.This newmethod will be illustrated by using the experiences of my daughter while a student in an elementa... The goal of this research is to explore a more successful method for Mainland Chinese students to learn English.This newmethod will be illustrated by using the experiences of my daughter while a student in an elementary school in the United States for oneyear.From the analysis of her learning experiences,the following conclusions were drawn:1) Immerse language learning is important tolanguage input.2) Phonics is an effective tool to improve reading for Chinese English 展开更多
关键词 language input learning methods PHONICS case study
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Structural Earthquake Resistance Design Using Energy Method
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作者 Hu Rongrong Civil Engineering Department, Huazhong University of Science and Technology, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第2期166-168,共3页
A summary of status of researches in the field of structural earthquake resistance design on energy concept is presented in three parts: earthquake input, demands on the structure and supplied capacity of the structur... A summary of status of researches in the field of structural earthquake resistance design on energy concept is presented in three parts: earthquake input, demands on the structure and supplied capacity of the structure. A new approach is proposed for analysis of the seismic response and damage criteria based on the momentary input energy. 展开更多
关键词 energy method maximum displacement momentary input energy.
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AN ANALYSIS ON INPUT IMPEDANCE OF A SINGLE MICROSTRIP PATCH IN THE QUASI-OPTICAL CAVITY
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作者 何宜军 杨铨让 《Journal of Electronics(China)》 1994年第2期150-155,共6页
The electromagnetic field integral equation in the quasi-optical cavity is obtained using the dyadic Green’s function. An expression is derived for the input impedance of a single microstrip patch cavity excited by a... The electromagnetic field integral equation in the quasi-optical cavity is obtained using the dyadic Green’s function. An expression is derived for the input impedance of a single microstrip patch cavity excited by a coaxial probe using moment method. The input impedance of a rectangular microstrip patch is discussed with this method. The result of this paper is similar to that of the microstrip antenna. This paper is of very important value for designing microstrip quasi-optical oscillator. 展开更多
关键词 OSCILLATOR Quasi-optical CAVITY input IMPEDANCE MICROSTRIP PATCH MOMENT method
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Electromagnetic Modeling of a Planar Structure Integrating a Via-Hole Using the Method FWCIP
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作者 Sameh Toumi Sahli Fethi Mejri Taoufik Aguili 《Open Journal of Antennas and Propagation》 2016年第2期64-84,共21页
We present in this paper a new formulation of the iterative method FWCIP “Fast Wave Concept Iterative Process” based on the wave concept. It calculates the electromagnetic parameters of a planar structure including ... We present in this paper a new formulation of the iterative method FWCIP “Fast Wave Concept Iterative Process” based on the wave concept. It calculates the electromagnetic parameters of a planar structure including a via-hole. This is modelled by the electromagnetic field that it creates in the structure. The validation of results found by this new formulation is ensured by comparison with those obtained by HFSS “high frequency structural simulator” software from Ansoft. They show that they are in good agreement. 展开更多
关键词 Microstrip Line Iterative method FWCIP Impedance input Planar Structure Via-Hole
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基于改进人工势场法的欠驱动无人船编队协同避碰避障 被引量:1
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作者 李伟 张永超 +3 位作者 宁君 马昊冉 刘陆 彭周华 《控制与决策》 北大核心 2025年第1期252-260,共9页
提出一种基于改进人工势场法且带有输入量化的欠驱动无人船编队协同避碰避障策略.借鉴导弹制导与控制机理,分层设计无人船运动学制导律与动力学控制律.首先,基于辅助变量法在无人船运动学子系统中设计分布式制导律,并引入改进人工势场... 提出一种基于改进人工势场法且带有输入量化的欠驱动无人船编队协同避碰避障策略.借鉴导弹制导与控制机理,分层设计无人船运动学制导律与动力学控制律.首先,基于辅助变量法在无人船运动学子系统中设计分布式制导律,并引入改进人工势场法的斥力函数.通过重构制导律实现运动学层面的协同避碰避障以及欠驱动无人船期望轨迹的跟踪;其次,通过使用径向基神经网络对无人船动力学子系统中的外界干扰和系统未建模动态进行逼近,采用均匀量化器对输入变量进行量化并对量化过程进行线性描述,使得底层量化控制器无需预测关于量化参数的具体信息;在稳定性分析中,利用李雅普诺夫稳定性理论证明所设计USV编队跟踪控制系统的稳定性;最后,采用Matlab对理论策略进行仿真实验,仿真结果验证了所提出策略的有效性. 展开更多
关键词 欠驱动无人船 人工势场法 分布式编队 输入量化 RBF神经网络 避障
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农业数字经济对农产品出口隐含碳的影响研究——以49个国家的面板数据为例
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作者 朱再清 张冰洁 《四川农业大学学报》 北大核心 2025年第5期1349-1359,共11页
【目的】研究农业数字经济与农产品出口隐含碳的关系,为减少全球贸易隐含碳排放,同时为中国实现"双碳"目标提供新思路。【方法】运用多区域投入产出模型测算2001-2020年49个国家的农产品出口隐含碳,通过双向固定效应、机制检... 【目的】研究农业数字经济与农产品出口隐含碳的关系,为减少全球贸易隐含碳排放,同时为中国实现"双碳"目标提供新思路。【方法】运用多区域投入产出模型测算2001-2020年49个国家的农产品出口隐含碳,通过双向固定效应、机制检验模型实证分析样本国家农业数字经济对农产品出口隐含碳的影响效应。【结果】①农业数字经济与农产品出口隐含碳排放量呈现显著的先增后减倒U形关系。②中低收入国家和亚洲大洋洲欧洲地区国家农业数字经济对农产品出口隐含碳的影响更大。③农业数字经济通过扩大农产品出口规模、促进绿色技术进步、优化能源结构3条路径影响农产品出口隐含碳。【结论】从农业数字经济发展、技术创新、能源结构优化等角度,进一步发挥农业数字经济的碳减排效应。 展开更多
关键词 农业数字经济 贸易隐含碳 多区域投入产出法 双向固定效应
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中国数字经济产业存在税收缺口问题吗?
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作者 张少华 陈鑫 黎美玲 《同济大学学报(社会科学版)》 北大核心 2025年第5期116-128,共13页
我国数字经济产业已经占据GDP的“半壁江山”,但是,中国数字经济产业是否存在税收缺口依然是“待解之谜”。本文运用基于直接消耗矩阵的投入产出表分解方法,通过对接现有国民经济核算体系来编制中国数字经济投入产出表,进而依托该表评... 我国数字经济产业已经占据GDP的“半壁江山”,但是,中国数字经济产业是否存在税收缺口依然是“待解之谜”。本文运用基于直接消耗矩阵的投入产出表分解方法,通过对接现有国民经济核算体系来编制中国数字经济投入产出表,进而依托该表评估中国数字经济产业的税收缺口问题。研究发现:(1)基于2017—2020年数据,我国数字经济产业不存在严重的税收缺口问题和贡献背离问题。尽管数字经济产业自身存在轻微的税收贡献不足问题,但是数字经济产业通过拉动其他产业发展带来了较大的间接税收贡献。(2)从数字经济细分行业的税收贡献来看,电信、互联网和相关服务、软件服务、房屋建筑、研究和试验发展等数字经济核心产业存在轻微的税收缺口问题,这些产业也正是造成实际生活中税收收入减少假象的那些行业。本研究对理解和促进我国数字经济和税收的均衡发展提供了学理支撑。 展开更多
关键词 投入产出表分解方法 数字经济投入产出表 “窄口径”税收缺口 “宽口径”税收缺口
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