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Science China Mathematics 2024年第7期67卷 1641-1664页

作者： Jinye Shen Fanhai Zeng Martin Stynes School of Mathematics Southwestern University of Finance and EconomicsChengdu611130China School of Mathematics Shandong UniversityJinan250100China Applied and Computational Mathematics Division Beijing Computational Science Research CenterBeijing100193China

Fractional initial-value problems(IVPs) and time-fractional initial-boundary value problems(IBVPs), each with a Caputo temporal derivative of order α ∈(0, 1), are considered. An averaged variant of the well-known L1 scheme is proved to be O(N^(-2)) convergent for IVPs on suitably graded meshes with N points, thereby improving the O(N^(-(2-α))) convergence rate of the standard L1 scheme. The analysis relies on a delicate decomposition of the temporal truncation error that yields a sharp dependence of the order of convergence on the degree of mesh grading used. This averaged L1 scheme can be combined with a finite difference or piecewise linear finite element discretization in space for IBVPs, and under a restriction on the temporal mesh width, one gets again O(N^(-2)) convergence in time, together with O(h^(2)) convergence in space,where h is the spatial mesh width. Numerical experiments support our results.

关键词： time-fractional subdiffusion averaged L1 scheme

Downstream Competition and Upstream Innovation:Theory and Evidence from China

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China finance and Economic Review 2024年第1期13卷 67-87页

作者： Jing Dai Guanchun Liu Ziqi Ye Haiou Mao Yongwei Ye School of finance Hubei University of Economics Lingnan College Sun Yatsen University School of Business Administration Zhongnan University of Economics and Law College of economics and Management Huazhong Agricultural University School of Public economics and Management Shanghai University of Finance and Economics

Competition is the catalyst of corporate innovation,which is the foundation of a country's core *** the view of vertical industrial chain,this paper examines how downstream competition affects upstream firms'innovation *** innovation helps reduce the production cost of each product,increasing demand of intermediate products caused by downstream competition enhances the marginal revenue of upstream firms'innovation,thus leading to an innovation incentive *** identify causality,we utilize China's WTO accession,a quasinatural experiment,to calculate downstream competition combined with import tariff reduction and input-output table,and then run a difference-in-difference *** the data of Annual Survey of Industrial Firms and State Intellectual Property Office,our results find that downstream competition has a significantly positive impact on upstream firms'innovation,and this effect is more pronounced in firms with less industry competition,greater initial innovation capacity and weaker financial ***,the number of firms,the degree of industry competition and the scale of intermediate products in the downstream sector increase,confirming the market size *** sum,our findings document that downstream competition can motivate upstream firms to innovate through vertical industrial chain,providing some useful insights for China to build a fair market competition environment and promote innovation-driven growth regime.

关键词： downstream competition upstream firms'innovation vertical industrial chain market size effect

Mathematical Model,Numerical Simulation and Convergence Analysis of a Semiconductor Device Problem with Heat and Magnetic Influences

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 302-319页

作者： Chang-feng LI Yi-rang YUAN Huai-ling SONG School of economics Shandong UniversityJinan 250100China Institute of Mathematics Shandong UniversityJinan 250100China College of Mathematics and Econometrics Hunan UniversityChangsha 410082China

In this paper,the authors discuss a three-dimensional problem of the semiconductor device type involved its mathematical description,numerical simulation and theoretical *** important factors,heat and magnetic influences are *** mathematical model is formulated by four nonlinear partial differential equations(PDEs),determining four major physical *** influences of magnetic fields are supposed to be weak,and the strength is parallel to the *** elliptic equation is treated by a block-centered method,and the law of conservation is *** computational accuracy is improved one *** equations are convection-dominated,thus are approximated by upwind block-centered *** difference can eliminate numerical dispersion and nonphysical *** diffusion is approximated by the block-centered difference,while the convection term is treated by upwind ***,the unknowns and adjoint functions are computed at the same *** characters play important roles in numerical computations of conductor device *** the theories of priori analysis such as energy estimates,the principle of duality and mathematical inductions,an optimal estimates result is *** a composite numerical method is shown for solving this problem.

关键词： three-dimensional conductor device problem with heat and magnetic influences upwind blockcentered differences elemental conservation of mass numerical analysis

Factor Price Distortion,Technological Innovation,and High-Quality Economic Development

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Frontiers of economics in China-Selected Publications from Chinese Universities 2024年第1期19卷 91-105页

作者： WANG Xiaoyun School of Accounting Dongbei University of Finance and EconomicsDalian 116025China School of Accounting Dalian University of Finance and EconomicsDalian 116622China

The entropy method is used to measure the high-quality economic development levels of 30 provinces(autonomous regions,municipalities)in China from 2011 to 2020,and the impacts of factor price distortion,technological innovation,and their interaction terms on high-quality economic development are analyzed based on Tobit *** results show that highquality economic development of 30 provinces(autonomous regions,municipalities)in China is on the rise;factor price distortion has an inhibitory effect on high-quality economic development,while technological innovation has a promoting effect on high-quality economic development,and both of them have a lag effect;technological innovation level can help alleviate the negative impact of factor price distortion on high-quality economic development;and sub-regional research shows that the inhibitory effect of factor price distortion on highquality economic development in the east is significantly higher than that in the central and western regions,but the positive effect of technological innovation and the interaction terms between the two on high-quality economic development is significantly lower than that in the central and western ***,it is proposed to optimize top-level design for the two-wheel drive for high-quality economic development,strengthen the primary role of enterprises in innovation to promote high-quality economic development,and optimize the market-oriented allocation of factors to improve the efficiency of resource allocation.

关键词： factor price distortion technological innovation high-quality economic development entropymethod

Dynamic Analysis of Incentive Policy Impacts on Recycling of Retired Batteries for Electric Vehicles

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Journal of Systems Science and Information 2024年第4期12卷 491-514页

作者： Cuixia WANG Lang WEI School of Information Management Jiangxi University of Finance and Economics School of economics and Management Hunan College of Information

Electric Vehicles(EVs), as a low-carbon means of transportation, have promptly become popular worldwide in the past decade. Since the lifespan of batteries is limited, massive of Electric Vehicle Batteries(EVBs) are being retired, resulting in a rapid increase in the demand for the recycling of retired EVBs in recent years. However, due to high recycling costs and immature recycling technologies, EV manufacturers are facing significant challenges in recycling retired EVBs. China, as the country with the largest number of EV users in the world, is exploring effective incentive policies for the recycling of retired EVBs. In this context, we developed a system dynamics model to analyze the impact of incentive polices such as, recycling subsidies, technological progress, and carbon trading on the retired EVBs recycling. Results show that: 1) recycling subsidies can improve the recycling ratios quickly in the short term, and dynamic subsidies are more efficient than static subsidies; 2) the policy of technological advancement can reduce the recovery and cascade utilization cost, thus having a positive impact on battery recycling, but the policy effect has a time-delay; 3) the carbon trading policy is unable to promote efficient recycling due to the current low carbon prices; 4) dynamic subsidy and technological advancement policies complement each other, therefore, the combination of these two policies is the best way to promote the recycling of retired EVBs and reduce carbon emissions. It is hoped that this study will contribute to the ongoing debate on policies for the industrialization of retired EVBs recycling.

关键词： electric vehicles retired battery recycling policy impact system dynamics

“China Shock”or China Dividend?-China GVC Participation’s Effects on Trading Partners’Technological Progress

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China Economist 2024年第1期19卷 44-57页

作者： Chen Qifei Yang Jijun Ye Di School of International economics and Trade Nanjing University of Finance and Economics(NUFE)NanjingChina School of Public finance and Taxation NUFE

This paper explores the effects of China’s global value chain(GVC)participation on technological progress in trading-partner countries based on estimated data on value-added trade between China and 52 trading *** find that,first,although China’s exports lowered the total factor productivity(TFP)of its trading partners(competitive effect),its imports greatly increased trading partners’TFP(effect of scale).This implies that China’s GVC participation is beneficial to its trading partners’technological progress in the form of a considerable technology dividend ***,China’s export dividend effect compensates for the negative effect of Chinese competition on trading partners’technological progress;the innovation effects attributable to China’s imports reinforce the positive effects of scale on technological *** innovation is factored in,the China dividend thus becomes further ***,China’s merchandise imports have a diminishing positive effect on technological progress in trading partners as geographical distance increases,but trade in services transcends geographical boundaries,and the positive technological progress effect of China’s service imports do not diminish as distance *** find that the“China dividend”from China’s GVC participation is a significant contributor to technological progress in partner nations,and China’s imports are conducive to innovation and technological progress in developed countries in the long run.

关键词： Global value chains China dividend trade in value-added technology spillover collaborative innovation

A new evolutional model for institutional field knowledge flow network

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Journal of Data and Information Science 2024年第1期9卷 101-123页

作者： Jinzhong Guo Kai Wang Xueqin Liao Xiaoling Liu School of Information Management Xinjiang University of Finance and EconomicsUrumqiChina

Purpose:This paper aims to address the limitations in existing research on the evolution of knowledge flow networks by proposing a meso-level institutional field knowledge flow network evolution model(IKM).The purpose is to simulate the construction process of a knowledge flow network using knowledge organizations as units and to investigate its effectiveness in replicating institutional field knowledge flow ***/Methodology/Approach:The IKM model enhances the preferential attachment and growth observed in scale-free BA networks,while incorporating three adjustment parameters to simulate the selection of connection targets and the types of nodes involved in the network evolution process Using the PageRank algorithm to calculate the significance of nodes within the knowledge flow *** compare its performance,the BA and DMS models are also employed for simulating the *** coefficient analysis is conducted on the simulated networks generated by the IKM,BA and DMS models,as well as on the actual ***:The research findings demonstrate that the IKM model outperforms the BA and DMS models in replicating the institutional field knowledge flow *** provides comprehensive insights into the evolution mechanism of knowledge flow networks in the scientific research *** model also exhibits potential applicability to other knowledge networks that involve knowledge organizations as node *** Limitations:This study has some ***,it primarily focuses on the evolution of knowledge flow networks within the field of physics,neglecting other ***,the analysis is based on a specific set of data,which may limit the generalizability of the *** research could address these limitations by exploring knowledge flow networks in diverse fields and utilizing broader *** Implications:The proposed IKM model offers practical implications for the construction and analysis of knowledge

关键词： Knowledge flow networks Evolutionary mechanism BA model Knowledge units

Global Spillovers of China's Monetary Policy

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China & World Economy 2024年第3期32卷 1-30页

作者： Wenni Lei Dongzhou Mei Mi Zhang School of economics Minzu University of ChinaChina School of International Trade and economics Central University of Finance and EconomicsChina

Spillovers from China's monetary policy have become increasingly obvious with China's growing importance in the global economy and its close economic and trade ties with the *** study establishes a proxy structure vector autoregression model to investigate the magnitude and transmission channel of spillovers from China to global and regional economies,taking advantage of high-frequency changes in asset prices in the financial markets to identify monetary policy *** analysis reveals that China's monetary policy can affect the global economy by influencing international trade and commodity prices but there is no evidence of China's monetary policy affecting global financial *** in China's monetary policy can cause a decline in world output whereas expansion in monetary policy can support global trade and *** study also finds that the response of emerging Asian economies to China's monetary policy shock was nearly twice that of developed economies,while the transmission path did not *** results of this study are consistent with the stylized fact that China's monetary policy plays an important role in the global trade and commodity cycle,although it does not drive the global financial cycle.

关键词： China's monetary policy commodity prices external instruments global trade spillovers

Foreign Ownership and International Trade Performance in China

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China & World Economy 2024年第2期32卷 42-72页

作者： Zhiyuan Li Yichun Lin Mingyao Xu School of economics Fudan University Shanghai Institute of International finance and economics China School of economics Fudan UniversityChina

We investigate the causal relationship between foreign ownership and international trade performance by comparing foreign-acquired firms with similar domestic-acquired firms in China with regard to changes in their post-acquisition international trade *** findings indicate that foreign ownership significantly enhanced the probability of both exporting and importing,and strongly increased trade *** ownership took effect from the year of the acquisition and persisted for at least 2 *** stimulated both processing trade and ordinary trade,and expanded products and trading ***-acquisition trade performance also exhibited heterogeneity based on the different pre-acquisition and post-acquisition *** for the underlying mechanisms,we show that firms experienced significant output expansion,increased export dependence,and eased financial constraints after foreign acquisition.

关键词： domestic acquisition foreign acquisition foreign ownership international trade performance

The Characteristics and Driving Factors of the Spatio-temporal Dynamic Evolution of Tourism Ecological Security in the Silk Road Economic Belt

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Journal of Resources and Ecology 2024年第4期15卷 1054-1067页

作者： WANG Shu LIU Fenglian YANG Lei CAI Wei Institute of Land&Resources and Sustainable Development Yunnan University of Finance and EconomicsKunming 650221China Institute of Economic Research Yunnan University of Finance and EconomicsKunming 650221China

The exploration of ecological safety in tourism sites can provide a concrete path for sustainable tourism development in a *** on the“Driver-Pressure-State-Impact-Response”(DPSIR)model,we constructed an index system for the evaluation of tourism ecological security(TES)in the Silk Road Economic Belt(SREB)from 2005 to *** index system was used to explore the characteristics of spatial and temporal dynamic evolution with the help of entropy weight TOPSIS method,dynamic index of TES and Markov probability transfer matrix,and a standard deviational ellipse(SDE)model and GM(1,1)model were constructed for spatial pattern analysis and *** results indicate four key aspects of this system.(1)In terms of spatiotemporal evolution,the tourism ecological safety index(TESI)of the SREB increased,the TES levels of the northwestern and southwestern provinces and cities differed significantly,and the quality conditions of TES in the southwestern provinces and cities were better than in the northwest.(2)In terms of dynamic evolutionary characteristics,the speed of change at each level of the SREB was slow,but the level of TES has *** TES level has not shifted by leaps and bounds,and the shifts in the level type show“path dependence”and“self-locking”effects.(3)In terms of spatial and temporal distribution patterns,the spatial pattern of TES in the SREB is a“northwest-southeast”movement trend,and the spatial distribution appeared as“aggregation”from 2005 to *** prediction results show that the center of gravity of TES in the SREB will shift to the southeast from 2025 to 2035,and the spatial spillover effect will be reduced.(4)In terms of driving factors,the number of star-rated hotels,and the amounts of industrial wastewater emissions,tourism foreign exchange earnings,forest coverage,and other parameters are the key factors affecting TES,and the booming tourism industry requires the interconnection and interpenetration of various *** resul

关键词： tourism ecological security spatial-temporal evolution drivers Geo-detector the Silk Road Economic Belt