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Unveiling the impact and mechanism of digital technology on agricultural economic resilience
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作者 Tianshu Quan Hui Zhang +1 位作者 Tianli Quan Yi Yu 《Chinese Journal of Population,Resources and Environment》 2024年第2期136-145,共10页
Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However... Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However,existing research predominantly focuses on traditional agricultural factors and technologies.Therefore,the impact of digital technology on agricultural economic resilience within the broader context of the“production-operation-industry”system in agriculture has not been comprehensively explored.To bridge this gap,this study analyzes panel data from 30 Chinese provinces from 2011 to 2020.It employs the static Van Dorn’s law and a dynamic spatial panel model to examine how digital technology empowers agricultural resilience.The findings indicate a continuous strengthening of digital technology development in China,albeit with significant polarization and spatial imbalances.Moreover,the resilience of the agricultural economy undergoes notable fluctuations,initially narrowing and subsequently displaying an upward trend.Digital technology clearly plays a pivotal role in empowering resilience through agricultural scale operation,industrial transformation,and technological progress.Its impact,particularly on the promotion of resilience in the eastern region and non-grain-producing areas and on high-level agricultural economies,also shows regional and technological variations. 展开更多
关键词 Digital technology Agricultural economic resilience Counterfactual method Dynamic spatial panel model Agricultural scale
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Critical Analysis of Increasingly Mathematical Economics in the Modern Society
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作者 YU Renze 《Management Studies》 2024年第4期248-251,共4页
This paper critically examines the escalating trend of mathematization in economics,highlighting its implications and controversies in contemporary economic research.While the application of sophisticated mathematical... This paper critically examines the escalating trend of mathematization in economics,highlighting its implications and controversies in contemporary economic research.While the application of sophisticated mathematical models and statistical techniques has enhanced the precision,rigor,and status of economics within academia and practical application,concerns arise regarding the potential oversimplification and detachment from real-world complexities.The adoption of mathematical tools has arguably led to a focus on theoretically tractable problems at the expense of those more relevant to practical economic and social issues.This paper explores both the benefits and limitations of this trend,discussing how the reliance on quantitative methods affects the innovation,comprehensibility,and application of economic theories.We argue for a balanced approach that fosters innovation by integrating qualitative insights and embracing interdisciplinary methods to ensure economics remains both rigorous and relevant to societal needs. 展开更多
关键词 mathematization of economics quantitative methods economic models interdisciplinary integration
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Evolution of economic linkage network of the cities and counties on the northern slope of the Tianshan Mountains,China
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作者 YANG Zeyu ZHANG Shubao +4 位作者 LEI Jun ZHANG Xiaolei TONG Yanjun DUAN Zuliang FAN Liqin 《Regional Sustainability》 2023年第2期173-184,共12页
The exchanges between cities and counties in the northern slope economic belt of Tianshan Mountains(NSEBTM)are increasingly frequent and the economic linkages are increasingly close,but the spatial distribution of eco... The exchanges between cities and counties in the northern slope economic belt of Tianshan Mountains(NSEBTM)are increasingly frequent and the economic linkages are increasingly close,but the spatial distribution of economic development and linkages among the cities and counties within NSEBTM is uneven.Therefore,it is of great significance to study the evolution of spatial-temporal pattern of the economic linkage network of cities and counties on NSEBTM to promote the coordinated and integrated development of the regional economy on NSEBTM.In this study,we used the modified gravity model and social network analysis method to analyze the spatio-temporal evolution characteristics of the economic linkage network structure of cities and counties on NSEBTM in 2000,2010,and 2020.The results showed that the comprehensive development quality level of cities and counties on NSEBTM increased from 2000 to 2020,its growth rate also increased,and its gap between cities and counties continued expanding.Both the spatial distribution patterns of the comprehensive development quality level of cities and counties on NSEBTM in 2000 and 2010 were presented as“high in the middle and low at both ends”,while the spatial distribution pattern of 2020 was exhibited as“high value and low value staggered”.The total amount of external economic linkages of cities and counties on NSEBTM showed an obvious upward trend,and its gap between cities and counties continued expanding,presenting a pattern of“a strong middle section and weak ends”.The direction of economic linkages of NSEBTM existed obvious central orientation and geographical proximity.The density of economic linkage network of NSEBTM increased from 2000 to 2020,and the structure of economic linkage network changed from single-core structure centered with Urumqi City to multicore structure centered with Urumqi City,Karamay City,Shihezi City,and Changji City,shifting from unbalanced development to balanced development.In the future,we should accelerate the construction of urban agglomeration on NSEBTM,cultivate a modern Urumqi metropolitan area,improve comprehensive development quality of the cities and counties at the eastern and western ends,strengthen the intensity of economic linkages between cities and counties,optimize the economic linkage network,and promote the coordinated and integrated development of regional economy. 展开更多
关键词 Entropy method economic linkages Gravity model Network structure Social network analysis Northern slope economic belt of Tianshan Mountains China
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The dynamic economic evaluation method of shale gas resources 被引量:2
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作者 Gang-yi Zhai Xiang-lin Chen +4 位作者 Xiang-hua Xia Zhi Zhou Tian-xu Guo Guo-heng Liu Rui-han Yuan 《China Geology》 2019年第2期211-217,共7页
At present, most shale gas exploration and development areas in China are difficult to provide sufficient and effective production data to support economic evaluation, since they are still in the initial stage of low ... At present, most shale gas exploration and development areas in China are difficult to provide sufficient and effective production data to support economic evaluation, since they are still in the initial stage of low exploration level. In addition, ecological and environmental factors are not taken into account in the evaluation process, which does not meet the needs of green energy development of China. Aiming at above problems, the dynamic economic evaluation method of shale gas resources based on calculus principle is proposed. The Arps hyperbolic decreasing curve model will be used in the evaluation of single shale gas well production, which can evaluate single well production of shale gas by fitting the existing dynamic production data to generate the production decreasing curve. Therefore, the variation regularity of the cumulative production of single well shale gas within the study area can be obtained by the model mentioned above. According to the variation regularity of the cumulative production obtained from the Arps hyperbolic decreasing curve model, the recovery period of single well cost, ultimate economic life and the ultimate economic resource can be evaluated dynamically by analyzing the variation regularity of the cumulative sales revenue and cumulative input cost of single shale gas well. Then the evaluation result can be further extend to the whole evaluation areas, in order to analyze shale gas resources ’ economic value in evaluation regions under different shale gas price conditions. The results of the above evaluation methods are not only conducive to improving the economic benefits of relative shale gas development enterprises, but also provide a basis for the national energy strategy deployment. 展开更多
关键词 SHALE gas Evaluation method economic RESOURCES Single WELL COST economic LIFE
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Dynamic Analysis of Coupling Relationship between Economic Development and Ecological Environment Based on Entropy Method——A Case Study of Xi'an City 被引量:1
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作者 YU Feng-ming DU Zhong-chao ZHOU Du-hui 《Meteorological and Environmental Research》 CAS 2011年第9期62-66,76,共6页
[Objective] The aim was to study the coupling relationship between economic development and ecological environment. [Method] Firstly, the evaluation index system for the coupling system of economic development and eco... [Objective] The aim was to study the coupling relationship between economic development and ecological environment. [Method] Firstly, the evaluation index system for the coupling system of economic development and ecological environment in Xi’an City was established, then the dynamic variation of coupling relationship between economic development and ecological environment in Xi’an City from 2001 to 2010 was analyzed by using entropy method, finally some corresponding suggestions were put forward according to the problems in the current development model. [Result] The economic development and ecological environment of Xi’an have made a significant upgrading and improvement from 2001 to 2010, namely showing a stable upward trend on the whole, and were in a well-coordinated development state in 2010. However, the development level of ecological environment obviously lagged behind economic development level. In addition, there were obvious differences in the development rate of sub-systems, that is, economic efficiency and economic level developed rapidly, while the carrying capacity of ecological environment and economic vitality grew slowly and unstably. [Conclusion] The research could provide theoretical bases for the establishment of strategies for the coordinated development economy and environment in Xi’an City. 展开更多
关键词 Entropy method economic development Ecological environment Xi'an City China
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Landscape Economics: Connotations, Basic Problems and Research Methods 被引量:1
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作者 LI Yongdong 《Journal of Landscape Research》 2015年第2期59-63,共5页
This paper analyzed necessity and laws of natural and cultural resource consumption and creation activities as a branch of economics or research direction, proposed such basic frameworks of landscape economics such as... This paper analyzed necessity and laws of natural and cultural resource consumption and creation activities as a branch of economics or research direction, proposed such basic frameworks of landscape economics such as connotations, basic problems and research methods on the basis of sorting out literature. Landscape economics is a social science focusing on the public preferences for natural and humanistic landscapes, and the preference evolution laws, economic laws of landscape resource consumption and creation activities. The basic problems include evaluation of landscape resource value, optimal utilization of landscape resources, landscape resource development and protection policies, formation and creation of diversified landscape structure. The research methods include investigation of consumers' willingness, experiment and behavioral economics, logical reasoning, and case study. 展开更多
关键词 Landscape economics CONNOTATION Basic problems Study method
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Economic Valuation of Auctioned Tourist Hunting Blocks in Tanzania
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作者 Reuben M. J. Kadigi Imani R. Nkuwi +2 位作者 Fredrick A. Ligate Hamza Kija Emmanuel B. Musamba 《Open Journal of Ecology》 2023年第4期199-228,共30页
Economic valuation of ecosystems is increasingly being recognized as an important exercise to inform sustainable utilization and conservation of natural assets. It helps in planning and establishing fair profit margin... Economic valuation of ecosystems is increasingly being recognized as an important exercise to inform sustainable utilization and conservation of natural assets. It helps in planning and establishing fair profit margins that accrue either directly or indirectly from the consumptive and non-consumptive uses of ecosystem goods and services. This paper is based on a study which estimated the economic values of tourist hunting blocks (HBs) in Tanzania using the Analytic Multicriteria Valuation Method (AMUVAM). The study used a sample size of 12 out of 24 vacant hunting blocks which were to be auctioned to potential hunting companies in December 2022. The economic values of HBs were estimated using the time horizon of 10 years (the mean tenure for winning company). The results show that the economic values ranged from USD 6,215,588 to USD 653,470,695 per hunting block and the Existence Value (EV) constituted about 19% of the Total Economic Value (TEV). EV ranged from USD 632,210 to USD 125,147,285. The study underscores the need for decisions to allocate ecosystems, such as HBs, to both direct and indirect uses, to be guided by a though understanding of their values. We further recommend building the capacity of staff charged with the role of managing and allocating uses of these ecosystems to enable them undertake economic valuation of ecosystems using both simple and more robust analytical tools, such as the GIS, relational databases, and worldwide websites based tools, like InVEST (Integrated Valuation of Environmental Services and Tradeoffs), ARIES (Artificial Intelligence for Ecosystem Services), and Co$ting Nature. 展开更多
关键词 ECOSYSTEMS Total economic Value Biodiversity Conservation Analytic Multicriteria Valuation method Hunting Blocks
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Dynamic economic dispatch combining network flow and interior point method 被引量:1
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作者 韩学山 赵建国 柳焯 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第4期461-466,共6页
Under the environment of electric power market, economic dispatch (ED) problem should consider network constraints, unit ramp rates, besides the basic constraints. For this problem, it is important to establish the ef... Under the environment of electric power market, economic dispatch (ED) problem should consider network constraints, unit ramp rates, besides the basic constraints. For this problem, it is important to establish the effective model and algorithm. This paper examines the decoupled conditions that affect the solution optimality to this problem. It proposes an effective model and solution method. Based on the look-ahead technique, it finds the number of time intervals to guarantee the solution optimality. Next, an efficient technique for finding the optimal solution via the interior point methods is described. Test cases, which include dispatching six units over 5 time intervals on the IEEE 30 test system with line flows and ramp constraints are presented. Results indicate that the computational effort as measured by iteration counts or execution time varies only modestly with the problem size. 展开更多
关键词 economic dispatch OPTIMIZATION network constraints ramp constraints interior point method
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Discussion on Collaborative Teaching of Econometrics in the Field of Environmental Economics
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作者 Wenhui Chen 《Journal of Contemporary Educational Research》 2023年第11期154-159,共6页
To capitalize on the synergies between the Econometrics course and the Environmental Economics major,this paper aims to enhance students’ability to conduct empirical analysis and practical application using econometr... To capitalize on the synergies between the Econometrics course and the Environmental Economics major,this paper aims to enhance students’ability to conduct empirical analysis and practical application using econometric models.It also seeks to promote collaborative teaching through case studies and model research.The primary focus is on the hot research issues within the field of environmental economics,utilizing the econometric model as a vehicle for instruction.To achieve this,the paper proposes the development of a comprehensive case library specific to environmental economics.This resource will serve to optimize the case teaching approach,incorporating the use of econometric software,and fostering interactive teaching models between educators and students.By implementing these strategies,the paper outlines a path and mode for collaborative teaching that effectively bridges the gap between econometrics and environmental economics. 展开更多
关键词 economETRICS Environmental economics Case teaching method
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A synthetic differencein-differences model for the influence of CR Express on Chongqing's economy
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作者 Rong Zhang Qi Li 《Railway Sciences》 2024年第3期295-310,共16页
Purpose-The China-Europe Railway Express(CR Express)in Chongqing has operated regularly and undergone large-scale development.Its impact on Chongqing's economic growth has become increasingly evident,necessitating... Purpose-The China-Europe Railway Express(CR Express)in Chongqing has operated regularly and undergone large-scale development.Its impact on Chongqing's economic growth has become increasingly evident,necessitating further research in this field.Design/methodology/approach-This study employs the opening of CR Express as a quasi-natural experiment,designating Chongqing,which inaugurated the CR Express in 2011,as the treatment group.13 provinces and cities that had not yet opened the CR Express until 2017 were selected as the control group.Utilizing panel data from 14 provinces across China spanning from 2006 to 2017,the synthetic control method(SCM)is employed to synthetically construct Chongqing.To quantify the difference in economic development levels between Chongqing with the operation of the CR express and Chongqing without its operation.Key metrics such as gross domestic product(GDP),per capita GDP,total retail sales of consumer goods,import and export value and the proportions of the secondary and tertiary industries are employed to measure urban economic development capabilities.Chongqing is designated as the experimental group,and a double-difference model is constructed to regress the operation of the CR Express against economic development capabilities.Robustness tests are conducted to validate the analytical results.Findings-The results indicate that,compared to provinces without the operation of the CR Express,the initiation of the CR Express in Chongqing significantly enhances the economic development level of the city.The opening of the CR Express exhibits a pronounced positive impact on Chongqing's economic development,and these findings remain robust and effective even after parallel trend tests and placebo tests.Originalitylvalue-The study represents an expansion of the theoretical framework.In contrast to previous studies that relied on a single indicator such as GDP,this study selects six indicators from the dimensions of economy,trade and industry to measure regional economic development capabilities.Furthermore,employing the grey relational analysis method,the study screens these indicators,thereby providing a theoretical basis for the selection of indicators for measuring regional economic development capabilities. 展开更多
关键词 CR Express Regional economic development Synthetic model Difference-indifferences method Papertype Research paper
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Method“Monte Carlo”in healthcare
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作者 Tsvetelina Velikova Niya Mileva Emilia Naseva 《World Journal of Methodology》 2024年第3期40-47,共8页
In public health,simulation modeling stands as an invaluable asset,enabling the evaluation of new systems without their physical implementation,experimentation with existing systems without operational adjustments,and... In public health,simulation modeling stands as an invaluable asset,enabling the evaluation of new systems without their physical implementation,experimentation with existing systems without operational adjustments,and testing system limits without real-world repercussions.In simulation modeling,the Monte Carlo method emerges as a powerful yet underutilized tool.Although the Monte Carlo method has not yet gained widespread prominence in healthcare,its technological capabilities hold promise for substantial cost reduction and risk mitigation.In this review article,we aimed to explore the transformative potential of the Monte Carlo method in healthcare contexts.We underscore the significance of experiential insights derived from simulated experimentation,especially in resource-constrained scenarios where time,financial constraints,and limited resources necessitate innovative and efficient approaches.As public health faces increasing challenges,incorporating the Monte Carlo method presents an opportunity for enhanced system construction,analysis,and evaluation. 展开更多
关键词 Monte Carlo SIMULATION Healthcare MODELING Decision analysis Stochastic methods Statistical techniques Health economics
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Analysis on the Effect of Statistical Method on Modern Economic Society
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作者 Ye Yuan 《Proceedings of Business and Economic Studies》 2019年第2期3-6,共4页
In recent years,with the continuous development and progress of society,people pay more and more attention to and pay attention to economics.In special modern society,the level of science and technology continues to i... In recent years,with the continuous development and progress of society,people pay more and more attention to and pay attention to economics.In special modern society,the level of science and technology continues to improve.Accurately grasp the economy and science and technology,in the modern economic society has a certain right and status.Therefore,the status of economics in the modern economic and social status is constantly improving,and statistical methods are a more commonly used tool in economics,statistical methods for the modern economic society has a very important role.The author probes into and analyzes the important role of statistical methods in modern economic society and puts forward the use of statistical methods in modern economic society,hoping to contribute to the development of modern economy and society. 展开更多
关键词 STATISTICAL methodS MODERN economic and SOCIAL FUNCTION
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The Principles and Methods of Power Development Planning in the Market Economic Situation of China
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《Electricity》 1999年第1期7-9,24,共4页
关键词 The Principles and methods of Power Development Planning in the Market economic Situation of China
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Techno-Economic and Sustainability Analysis of Potential Cooling Methods in Irish Data Centres
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作者 Lee Gibbons Tim Persoons Sajad Alimohammadi 《Journal of Electronics Cooling and Thermal Control》 2021年第3期35-54,共20页
11% of Irish electricity was consumed by data centres in 2020. The Irish data centre industry and the cooling methods utilised require reformative actions in the coming years to meet EU Energy policies. The resell of ... 11% of Irish electricity was consumed by data centres in 2020. The Irish data centre industry and the cooling methods utilised require reformative actions in the coming years to meet EU Energy policies. The resell of heat, alternative cooling methods or carbon reduction methods are all possibilities to conform to these policies. This study aims to determine the viability of the resell of waste heat from data centres both technically and economically. This was determined using a novel application of thermodynamics to determine waste heat recovery potential in Irish data centres, and the current methods of heat generation for economical comparison. This paper also explores policy surrounding waste heat recovery within the industry. The Recoverable Carnot Equivalent Power (RCEP) is theoretically calculated for the three potential cooling methods for Irish data centres. These are air, hybrid, and immersion cooling techniques. This is the maximum useable heat that can be recovered from a data centre rack. This study is established under current operating conditions which are optimised for cooling performance, that air cooling has the highest potential RCEP of 0.39 kW/rack. This is approximately 8% of the input electrical power that can be captured as useable heat. Indicating that Irish data centres have the energy potential to be heat providers in the Irish economy. This study highlighted the technical and economic aspects of prevalent cooling techniques and determined air cooling heat recovery cost can be reduced to 0.01 €/kWhth using offsetting. This is financially competitive with current heating solutions in Ireland. 展开更多
关键词 IRELAND Data Centres TECHNO-economic Novel Cooling methods Heat Resell SUSTAINABILITY Energy Demand
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ADMM-based Distributed Algorithm for Economic Dispatch in Power Systems With Both Packet Drops and Communication Delays 被引量:5
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作者 Qing Yang Gang Chen Ting Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第3期842-852,共11页
By virtue of alternating direction method of multipliers(ADMM), Newton-Raphson method, ratio consensus approach and running sum method, two distributed iterative strategies are presented in this paper to address the e... By virtue of alternating direction method of multipliers(ADMM), Newton-Raphson method, ratio consensus approach and running sum method, two distributed iterative strategies are presented in this paper to address the economic dispatch problem(EDP) in power systems. Different from most of the existing distributed ED approaches which neglect the effects of packet drops or/and time delays, this paper takes into account both packet drops and time delays which frequently occur in communication networks. Moreover, directed and possibly unbalanced graphs are considered in our algorithms, over which many distributed approaches fail to converge. Furthermore, the proposed schemes can address the EDP with local constraints of generators and nonquadratic convex cost functions, not just quadratic ones required in some existing ED approaches. Both theoretical analyses and simulation studies are provided to demonstrate the effectiveness of the proposed schemes. 展开更多
关键词 ALTERNATING direction method of multipliers(ADMM) average consensus directed graph(digraph) distributed algorithm economic DISPATCH packet DROPS time DELAYS
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Dynamic Economic Dispatch for Wind Power System Considering System Security and Spinning Reserve 被引量:1
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作者 Wangchao Dong Jing Zhang +1 位作者 Jiejie Huang Shenghu Li 《Journal of Power and Energy Engineering》 2015年第4期342-347,共6页
In this paper, dynamic economic dispatch model is proposed for power systems with bulk wind power integration. The wind turbine generators are assumed to partially undertake the spinning reserve for the thermal genera... In this paper, dynamic economic dispatch model is proposed for power systems with bulk wind power integration. The wind turbine generators are assumed to partially undertake the spinning reserve for the thermal generator. A double-layer optimization model is proposed. The outer layer use the differential evolution to search for the power output of thermal generators, and the inner layer use the primal-dual interior point method to solve the OPF of the established output state. Finally, the impact of spinning reserve with wind power on power system operating is validated. 展开更多
关键词 SPINNING RESERVE Wind Power Dynamic economic DISPATCH (DED) Differential Evolution method INTERIOR Point method
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The Role of China's High-Tech Zones in Its Regional Economic Development 被引量:2
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作者 刘瑞明 赵仁杰 《China Economist》 2016年第5期44-56,共13页
National high-tech industrial development zones represent a major strategy of the Chinese government in developing high-tech industries and spurring regional economic growth. The effect of this policy is yet to be pro... National high-tech industrial development zones represent a major strategy of the Chinese government in developing high-tech industries and spurring regional economic growth. The effect of this policy is yet to be proven. Based on the panel data of 283 Chinese cities between 1984 and 2012, this paper investigates the effect of high-tech zones on regional economic development. Empirical results suggest that first, national hightech zones have remarkably enhanced regional GDP and per capita GDP growth, and this conclusion still holds true after multiple rounds of robustness test; second, the economic effect of national high-tech zones is subject to diminishing marginal return and compared with higher-tier cities, lower-tier cities benefited more from the creation of national hightech zones. This paper concludes that national high-tech zones where special policies are experimented and offered not only drive economic development but, if properly distributed across regions, may help reduce regional economic disparities as well. The results of this study provide important implications for the future distribution of national high-tech zones and the creation of other relevant policies. 展开更多
关键词 national high-tech zones regional economic growth difference-in-differences method
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Interconnections between governance and socioeconomic conditions:Understanding the challenges in sub-Saharan Africa 被引量:1
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作者 Fisayo FAGBEMI Geraldine Ejiaka NZERIBE +1 位作者 Tolulope Temilola OSINUBI Simplice ASONGU 《Regional Sustainability》 2021年第4期337-348,共12页
Given that challenges on the issue of socioeconomic development faced by countries in sub-Saharan Africa(SSA)have been identified as critical to strengthening the inherent link between governance and socioeconomic con... Given that challenges on the issue of socioeconomic development faced by countries in sub-Saharan Africa(SSA)have been identified as critical to strengthening the inherent link between governance and socioeconomic conditions,this study examines the interconnections between governance and socioeconomic conditions in SSA.With a focus on 25 countries in SSA between 2005 and 2019,we conduct the analysis based on the Panel-Corrected Standard Error and System Generalized Method of Moments estimations and panel causality tests.The results show that SSA does not seem to have the means of effective governance to spur improved socioeconomic conditions.Moreover,the pervasiveness of institutional problems in many countries of SSA has been responsible for the poor socioeconomic conditions in the region.Likewise,governance quality and socioeconomic conditions are found to influence each other.An improvement in socioeconomic conditions could result in better governance quality.On the other hand,governance quality is viewed as a vital ingredient in achieving needed socioeconomic development outcomes.Thus,it is suggested that there is a need for countries in SSA to streamline governing systems toward engendering improved well-being.The introduction and implementation of transformative policies through effective governance are also necessary for ensuring critical structural changes and increasing social service provision.Overall,there should be a proactive identification of ineffective policies and procedures by policymakers to enhance meaningful impacts in the region. 展开更多
关键词 Governance quality SOCIOeconomic CONDITIONS economic development System Generalized method of Moments Sub-Saharan Africa
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A Chance Constrained Optimal Reserve Scheduling Approach for Economic Dispatch Considering Wind Penetration 被引量:2
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作者 Yufei Tang Chao Luo +1 位作者 Jun Yang Haibo He 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第2期186-194,共9页
The volatile wind power generation brings a full spectrum of problems to power system operation and management, ranging from transient system frequency fluctuation to steady state supply and demand balancing issue. In... The volatile wind power generation brings a full spectrum of problems to power system operation and management, ranging from transient system frequency fluctuation to steady state supply and demand balancing issue. In this paper, a novel wind integrated power system day-ahead economic dispatch model, with the consideration of generation and reserve cost is modelled and investigated. The proposed problem is first formulated as a chance constrained stochastic nonlinear programming U+0028 CCSNLP U+0029, and then transformed into a deterministic nonlinear programming U+0028 NLP U+0029. To tackle this NLP problem, a three-stage framework consists of particle swarm optimization U+0028 PSO U+0029, sequential quadratic programming U+0028 SQP U+0029 and Monte Carlo simulation U+0028 MCS U+0029 is proposed. The PSO is employed to heuristically search the line power flow limits, which are used by the SQP as constraints to solve the NLP problem. Then the solution from SQP is verified on benchmark system by using MCS. Finally, the verified results are feedback to the PSO as fitness value to update the particles. Simulation study on IEEE 30-bus system with wind power penetration is carried out, and the results demonstrate that the proposed dispatch model could be effectively solved by the proposed three-stage approach. © 2017 Chinese Association of Automation. 展开更多
关键词 Constrained optimization economicS Electric load flow Electric power generation Intelligent systems Monte Carlo methods Nonlinear programming Optimization Particle swarm optimization (PSO) Problem solving Quadratic programming SCHEDULING Stochastic systems Wind power
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Assessment of China's economic loss resulting from the degradation of agricultural land in the end of 20th century
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作者 HAOFang-hua CHANGYing NINGDa-tong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期199-203,共5页
Land degradation is a consequence stemming from both natural processes and social economic activities. On the bases of analyzing general situation of agricultural land degradation in China, the monetary estimating met... Land degradation is a consequence stemming from both natural processes and social economic activities. On the bases of analyzing general situation of agricultural land degradation in China, the monetary estimating methods such as market value method and shadow engineering method were used to quantitatively assess the economic loss resulting from land deterioration. Results showed that the economic loss in 1999 was 326 81 billion RMB Yuan, which accounted for 4 1% of GDP in the same year of China. If taking five items namely farmland conversion, soil erosion, salinization, decline in reservoir functions, and siltation in waterways and, comparing with that in 1992, the percentage of economic loss to GDP has increased by 1 5 in the only 7 years. 展开更多
关键词 agricultural land DEGRADATION economic loss estimating method China
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