With the trade network analysis method and bilateral country-product level trade data of 2017-2020,this paper reveals the overall characteristics and intrinsic vulnerabilities of China’s global supply chains.Our rese...With the trade network analysis method and bilateral country-product level trade data of 2017-2020,this paper reveals the overall characteristics and intrinsic vulnerabilities of China’s global supply chains.Our research finds that first,most global supply-chain-vulnerable products are from technology-intensive sectors.For advanced economies,their supply chain vulnerabilities are primarily exposed to political and economic alliances.In comparison,developing economies are more dependent on regional communities.Second,China has a significant export advantage with over 80%of highly vulnerable intermediate inputs relying on imports of high-end electrical,mechanical and chemical products from advanced economies or their multinational companies.China also relies on developing economies for the import of some resource products.Third,during the trade frictions from 2018 to 2019 and the subsequent COVID-19 pandemic,there was a significant reduction in the supply chain vulnerabilities of China and the US for critical products compared with other products,which reflects a shift in the layout of critical product supply chains to ensure not just efficiency but security.China should address supply chain vulnerabilities by bolstering supply-side weaknesses,diversifying import sources,and promoting international coordination and cooperation.展开更多
Based on the analysis of rice planting and export development in Heilongjiang Province in 2013-2021,this paper comprehensively used three export competitiveness analysis methods,namely,trade competitiveness index,reve...Based on the analysis of rice planting and export development in Heilongjiang Province in 2013-2021,this paper comprehensively used three export competitiveness analysis methods,namely,trade competitiveness index,revealed comparative advantage(RCA)analysis and international market share analysis,to compare the four major rice exporters in the world and the three major rice export provinces and cities in China.Besides,it evaluated the rice export competitiveness of Heilongjiang Province from multiple perspectives.It analyzed the reasons for low competitiveness in terms of export product structure,export market structure,production and processing technology,and brand building.Finally,it is recommended to clarify the positioning of rice export quality and take more measures to ensure product quality;improve the level of industrialization of rice production and processing,and extend the rice industry chain;develop diversified rice export markets and improve export flexibility;adhere to the principle of"opening the door and going out",expand the international popularity of high-quality brands,so as to enhance the rice export competitiveness of Heilongjiang Province.展开更多
针对源网荷储优化调度时分布式电源的间歇性引起主动配电网节点电压波动以及有功网损增加等问题,提出一种改进风光场景聚类联合虚拟储能的源网荷储低碳优化调度方法。首先,为有效应对风光出力不确定的挑战,提出一种基于密度噪声应用空...针对源网荷储优化调度时分布式电源的间歇性引起主动配电网节点电压波动以及有功网损增加等问题,提出一种改进风光场景聚类联合虚拟储能的源网荷储低碳优化调度方法。首先,为有效应对风光出力不确定的挑战,提出一种基于密度噪声应用空间聚类(density-based spatial clustering of applications with noise,DBSCAN)的迭代自组织数据分析算法(iterative self-organizing data analysis techniques algorithm,ISODATA),并以DB指数、Dunn指数和轮廓系数对风光场景聚类效果的优劣进行评价。其次,引入阶梯式碳交易机制,建立以主动配电网综合运行成本最低为目标的优化调度模型。同时,提出用户参与满意度和电网依赖度两种运行评价指标。最后,在IEEE 33节点系统上进行算例仿真分析,结果验证了DBSCAN-ISODATA算法的合理性。并且所提低碳优化调度方法能够有效降低系统碳排放量与运行成本,实现了主动配电网低碳经济稳定运行。展开更多
文摘With the trade network analysis method and bilateral country-product level trade data of 2017-2020,this paper reveals the overall characteristics and intrinsic vulnerabilities of China’s global supply chains.Our research finds that first,most global supply-chain-vulnerable products are from technology-intensive sectors.For advanced economies,their supply chain vulnerabilities are primarily exposed to political and economic alliances.In comparison,developing economies are more dependent on regional communities.Second,China has a significant export advantage with over 80%of highly vulnerable intermediate inputs relying on imports of high-end electrical,mechanical and chemical products from advanced economies or their multinational companies.China also relies on developing economies for the import of some resource products.Third,during the trade frictions from 2018 to 2019 and the subsequent COVID-19 pandemic,there was a significant reduction in the supply chain vulnerabilities of China and the US for critical products compared with other products,which reflects a shift in the layout of critical product supply chains to ensure not just efficiency but security.China should address supply chain vulnerabilities by bolstering supply-side weaknesses,diversifying import sources,and promoting international coordination and cooperation.
基金Social Science Planning Project of Xi an City(JG140)Bidding Project of Buchang Xixian Economic Research Institute(SMZX202113).
文摘Based on the analysis of rice planting and export development in Heilongjiang Province in 2013-2021,this paper comprehensively used three export competitiveness analysis methods,namely,trade competitiveness index,revealed comparative advantage(RCA)analysis and international market share analysis,to compare the four major rice exporters in the world and the three major rice export provinces and cities in China.Besides,it evaluated the rice export competitiveness of Heilongjiang Province from multiple perspectives.It analyzed the reasons for low competitiveness in terms of export product structure,export market structure,production and processing technology,and brand building.Finally,it is recommended to clarify the positioning of rice export quality and take more measures to ensure product quality;improve the level of industrialization of rice production and processing,and extend the rice industry chain;develop diversified rice export markets and improve export flexibility;adhere to the principle of"opening the door and going out",expand the international popularity of high-quality brands,so as to enhance the rice export competitiveness of Heilongjiang Province.
文摘针对源网荷储优化调度时分布式电源的间歇性引起主动配电网节点电压波动以及有功网损增加等问题,提出一种改进风光场景聚类联合虚拟储能的源网荷储低碳优化调度方法。首先,为有效应对风光出力不确定的挑战,提出一种基于密度噪声应用空间聚类(density-based spatial clustering of applications with noise,DBSCAN)的迭代自组织数据分析算法(iterative self-organizing data analysis techniques algorithm,ISODATA),并以DB指数、Dunn指数和轮廓系数对风光场景聚类效果的优劣进行评价。其次,引入阶梯式碳交易机制,建立以主动配电网综合运行成本最低为目标的优化调度模型。同时,提出用户参与满意度和电网依赖度两种运行评价指标。最后,在IEEE 33节点系统上进行算例仿真分析,结果验证了DBSCAN-ISODATA算法的合理性。并且所提低碳优化调度方法能够有效降低系统碳排放量与运行成本,实现了主动配电网低碳经济稳定运行。
