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Dynamic evolution and trend prediction of multi-scale green innovation in China
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作者 Xiaohua Xin Lachang Lyu Yanan Zhao 《Geography and Sustainability》 CSCD 2023年第3期222-231,共10页
Numerous studies deal with spatial analysis of green innovation(GI).However,researchers have paid limited attention to analyzing the multi-scale evolution patterns and predicting trends of GI in China.This paper seeks... Numerous studies deal with spatial analysis of green innovation(GI).However,researchers have paid limited attention to analyzing the multi-scale evolution patterns and predicting trends of GI in China.This paper seeks to address this research gap by examining the multi-scale distribution and evolutionary characteristics of GI activities based on the data from 337 cities in China during 2000-2019.We used scale variance and the two-stage nested Theil decomposition method to examine the spatial distribution and inequalities of GI in China at multiple scales,including regional,provincial,and prefectural.Additionally,we utilized the Markov chain and spatial Markov chain to explore the dynamic evolution of GI in China and predict its long-term development.The findings indicate that GI in China has a multi-scale effect and is highly sensitive to changes in spatial scale,with significant spatial differences of GI decreasing in each scale.Furthermore,the spatiotemporal evolution of GI is influenced by both geospatial patterns and spatial scales,exhibiting the“club convergence”effect and a tendency to transfer to higher levels of proximity.This effect is more pronounced on a larger scale,but it is increasingly challenging to transfer to higher levels.The study also indicates a steady and sustained growth of GI in China,which concentrates on higher levels over time.These results contribute to a more precise understanding of the scale at which GI develops and provide a scientific basis and policy suggestions for optimizing the spatial structure of GI and promoting its development in China. 展开更多
关键词 Green innovation Spatial pattern Trend prediction MULTI-SCALE China
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Enhancing Autonomy Capability in Regional Power Grids:A Strategic Planning Approach with Multiple Autonomous Evaluation Indexes
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作者 Jie Ma Tong Zhao +8 位作者 Yuanzhao Hao Wenwen Qin Haozheng Yu Mingxuan Du Yuanhong Liu Liang Zhang Shixia Mu Cuiping Li Junhui Li 《Energy Engineering》 EI 2024年第9期2449-2477,共29页
After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and de... After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and demand in the distribution network,exacerbating the phenomenon of wind and solar power wastage.As a novel power system model,the fundamental concept of Regional Autonomous Power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of DGs.Therefore,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for autonomy.First,a regional Energy Storage(ES)configuration strategy is proposed.This strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES capacity.Then,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy capabilities.The final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on average.The proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluctuation of power exchange between the regional grid and the higher-level grid.This presents a rational and effective planning solution for the regional grid,facilitating the coordinated development between the region and the distribution network. 展开更多
关键词 Regional autonomous power grid distributed generation distributed energy storage regional planning strategy evaluation index
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Innovation-based urbanization: Evidence from 270 cities at the prefecture level or above in China 被引量:11
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作者 LYU Lachang SUN Feixiang HUANG Ru 《Journal of Geographical Sciences》 SCIE CSCD 2019年第8期1283-1299,共17页
With the rapid development of knowledge economy, a number of important shifts are emerging in urbanization pattern across the world. Traditional urbanization theory has become hard to interpret these changes on a glob... With the rapid development of knowledge economy, a number of important shifts are emerging in urbanization pattern across the world. Traditional urbanization theory has become hard to interpret these changes on a global scale, and 'innovation' is a core concept to explain the new changes of the urbanization dynamics. As one of the important contents of urban geography, urbanization dynamic needs to turn from the general population flows between rural and urban areas into emphasizing high skilled migrants flow among cities and regions research. Against this background, we propose a conception of innovation-based urbanization. Using this concept, this study analyzes the spatial distribution characteristics of high skilled migrants and cultural diversity on urban innovation in China, based on the data of the sixth census of 270 cities at the prefecture level or above in China. This study measures the extent to which highly skilled migrants and cultural diversity increase urban innovation, by using spatial Durbin method to construct urban innovation regression model, to support the concept of innovation-based urbanization. The result shows that: first of all, the concept of innovation-based urbanization conforms to the development of knowledge economy, which emphasizes the migration process of highly skilled labor to cities. It helps to promote the changes in urban functions and landscapes and the expansion of urban knowledge activities, which undelines new dynamics of urban development, innovative landscape. Secondly, innovation urbanization based on highly skilled migrants flow is an important driving force for the development of Chinese cities, especially for eastern coastal cities and capital cities. Thirdly, the scale of highly skilled migrants flow and the level of urban cultural diversity in China both have been demonstrated of having positive effect on urban innovation output. With other conditions unchanged, a 10% increase in the number of urban highly skilled migrants and urban cultural diversity will directly result in an increase of 3% and 2% in urban innovation output respectively. This research has deepened our understanding and awareness of the openness and dynamics of the regional innovation system, and it has also provided an important theoretical basis for the formulation of urbanization and urban development policy under knowledge economy. 展开更多
关键词 innovation-based URBANIZATION INNOVATION URBANIZATION highly SKILLED labor MIGRANTS cultural diversity China
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Upgrading of Technological Capability and Innovation Policy Transformation in China under a New Situation 被引量:2
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作者 Mingjie Ma Hongru Xiong 《Innovation and Development Policy》 2020年第2期83-98,共16页
Countries worldwide are actively pushing their innovation frontiers into the profound globalized innovation networks.China is entering into a new phase that experiences the profound transformation of the innovation sy... Countries worldwide are actively pushing their innovation frontiers into the profound globalized innovation networks.China is entering into a new phase that experiences the profound transformation of the innovation systems and supporting policies,together with facing the accelerated technological innovation and emerging de-globalization trends.Improving the institution of innovation-driven development,as well as the quality and efficiency of innovation,are beneficial for China to integrate into the global innovation network and move towards the technological frontiers.This study analyzes the phases of the ongoing industrial innovation in China from the techno-economic perspective and proposes a multiplefactor framework to explore indigenous technological innovations.We suggest that the factors impacting technological upgrading and innovation capability are technological gaps,complexities of industrial ecology,the density of capital,and market need complexities under open competition conditions.These factors are necessary but not sufficient conditions for the success of cultivating the capability of technological innovations.The government must fulfill its roles adequately and effectively and pay more attention to the limits and focus of innovation policies.We propose that China’s innovation policies need to be flexible towards the changing world’s opportunities and challenges.China needs to boost its strengths towards an initiative and exploring role in the global innovation scene.Solid fundamental research and applications urgently need to support the layout of the upgrading of technological capabilities that bundled by greater openness and inclusiveness.Meanwhile,policies need to be transformed to guarantee equal benefits and greater tolerance to deliver an innovation-friendly system. 展开更多
关键词 technological capability innovation policy transformation techno-economic factors China
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中国城市知识创新职能空间分异及其影响因素 被引量:1
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作者 于英杰 吕拉昌 《Journal of Geographical Sciences》 SCIE CSCD 2023年第6期1161-1184,共24页
Knowledge innovation is a key component of urban innovation function and an important basis for modern urban development. Combining the multidisciplinary research of knowledge innovation, this paper constructs a measu... Knowledge innovation is a key component of urban innovation function and an important basis for modern urban development. Combining the multidisciplinary research of knowledge innovation, this paper constructs a measurement framework of urban knowledge innovation function from the perspective of urban geography and analyzes its spatial pattern and influencing factors. The conclusions are as follows:(1) The function of urban knowledge innovation refers to the tasks and roles it undertakes in the process of knowledge creation, knowledge dissemination and knowledge application, which is based on the internal knowledge stock and external practice conditions to meet the needs of human survival and development in the new era. The measurement dimensions include functional scale, functional intensity, functional scale, and functional vitality.(2) The development level of knowledge innovation functions in Chinese cities is uneven, and the cities with outstanding knowledge innovation functions are mainly concentrated in the eastern coastal areas and a few developed areas in the central and western regions, forming the diamond-shaped knowledge innovation structure with the Beijing-Tianjin, the Yangtze River Delta, the Pearl River Delta, Shaanxi-Chengdu-Chongqing as the four vertices and central Wuhan and Hefei as the center. According to the Jenks natural breakpoint method, it is divided into national-level, regional-level, local-level and knowledge-innovative development cities.(3) The spatial differentiation characteristics of urban knowledge innovation function are simultaneously affected by various natural and human factors. Among them, economic environment, opening environment, and cultural environment have the strongest interactive explanatory power with other factors, and are the dominant factors affecting the city’s knowledge innovation function. In the future, China should fully considers the status and characteristics of the city’s own knowledge economy development with corresponding policies and measures suitable for the development of the city’s knowledge economy, and strengthen the dominant position of human and social factors in the constructing the city’s knowledge innovation function. 展开更多
关键词 knowledge innovation function function magnitude function intensity function vitality function scale influencing factors
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An efficient graph data compression model based on the germ quotient set structure 被引量:1
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作者 Dawei WANG Wanqiu CUI 《Frontiers of Computer Science》 SCIE EI CSCD 2022年第6期195-197,共3页
1 Introduction The graph data model is a crucial foundation of the graph database and has been extensively applied with relational data,such as knowledge graphs,etc.Social networks[1]trigger the discussion of a lot of... 1 Introduction The graph data model is a crucial foundation of the graph database and has been extensively applied with relational data,such as knowledge graphs,etc.Social networks[1]trigger the discussion of a lot of hot topics,which leads to a proliferation of highly repetitivedata.Therefore,how to design a graph data compression model is key to effectively storing dense graphs[2]. 展开更多
关键词 QUOTIENT GRAPHS STRUCTURE
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