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Spatial-temporal Evolution of the Urban-rural Coordination Relationship in Northeast China in 1990-2018 被引量:4
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作者 WANG Ying CHEN Xiaohong +2 位作者 SUN Pingjun LIU Hang HE Jiaxin 《Chinese Geographical Science》 SCIE CSCD 2021年第3期429-443,共15页
To comprehensively understand the law of urban-rural relationship and propose scientific measures of urban-rural coordinated development in Northeast China,this study uses the coupling coordination degree model and ge... To comprehensively understand the law of urban-rural relationship and propose scientific measures of urban-rural coordinated development in Northeast China,this study uses the coupling coordination degree model and geographically and temporally weighted regression(GTWR)model to analyze the spatial-temporal patterns and the corresponding driving mechanisms of its urban-rural coordination since 1990.The results are as follows.First,the urban-rural coupling coordination degree in Northeast China was very low and improved slowly,but its stages of evolution is a good interpretation of the strategic arrangements of China's urbanization.Second,the urban-rural coupling coordination degree in Northeast China had spatial differences and was characterized by central polarization,converging on urban agglomeration,which was high in the south and low in the north.Moreover,the gap between the north and south weakened.Third,the spatial-temporal evolution of the urban-rural coordination relationship in Northeast China was influenced by pulling from the central cities,pushing from rural transformation,and government regulations.The influence intensity of the three mechanisms was weak,but the pulling from the central cities was stronger than that of the other two mechanisms.Furthermore,the spatial difference between the three mechanisms determines the spatial pattern and its evolution of the urban-rural coordination relationship in Northeast China.Fourth,to promote the development of urban-rural coordination in Northeast China,it is essential to advance urban-rural economic correlation,enhance the government^role in regulating and guiding,and adopt different policies for each region in Northeast China. 展开更多
关键词 urban-rural coordination relationship spatial-temporal evolution coupling coordination degree model geographically and temporally weighted regression(GTWR) Northeast China
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Precipitation and soil texture dominate the spatiotemporal changes in the carbon-water coupling coordination in Taihang Mountains, China
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作者 LI Xin CHEN Yanmei +3 位作者 LI Suyan SUN Xiangyang LIU Qi WANG Hongzhou 《Journal of Geographical Sciences》 2025年第3期521-551,共31页
The Taihang Mountains in North China are an important carbon-water ecosystem service supply area.Understanding the coupling effect and influencing mechanisms of mountain carbon sequestration as well as water conservat... The Taihang Mountains in North China are an important carbon-water ecosystem service supply area.Understanding the coupling effect and influencing mechanisms of mountain carbon sequestration as well as water conservation is essential for regional eco-logical restoration and sustainable development.In this study,we utilized models such as the coupled coordination degree model,the random forest and Geodetector to analyze the spa-tio-temporal changes as well as driving factors of carbon sequestration-water conservation coupling coordination in the Taihang Mountains.The results show that:(1)From 1990 to 2020,the carbon sequestration and water conservation capacity of the Taihang Mountains exhibited a spatial pattern with higher values in the southeast and central regions,while lower values in the northwest region.(2)The average coupling coordination degree from 1990 to 2020 was O.23,which was overall low,with a fluctuating decreasing-rising-decreasing trend over time.The coupling coordination degree exhibited a pattern that is high in the middle and low in the periphery,with a fluctuating distribution that initially decreases and then increases with the increasing altitude.The overall trend of coupling coordination is degradation,with concen-trated degradation in the northwest mountainous regions.(3)Precipitation and soil texture were identified as the main driving factors influencing coupling coordination,with the interac-tion between precipitation and soil sand content showing the strongest explanatory power,while that among topography,vegetation and human activities had relatively low explanatory power.Therefore,enhanced protection and the continuous monitoring of vegetation and soil environments in the Taihang Mountains are essential,with particular emphasis on ecological restoration in areas experiencing a persistent degradation of carbon-water coupling.This study can provide assistance in monitoring and managing carbon sink and water resources in the mountains,meanwhile mitigating potential adverse impacts on human well-being. 展开更多
关键词 carbon sequestration water conservation coupling coordination relationships driving factors Tai-hangMountains
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Insight into the Relationship Between Local Coordination of Isolated Pt Atoms and Chemical Reactivity
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作者 赵梓俨 周莹 《材料导报》 EI CAS CSCD 北大核心 2019年第14期2281-2282,共2页
The supported isolated Pt atoms(Pt iso)and other rare metals have attracted intensive concern due to their maximized metal utilization efficiency,unique reactivity or selectivity,connection to organometallic catalysis... The supported isolated Pt atoms(Pt iso)and other rare metals have attracted intensive concern due to their maximized metal utilization efficiency,unique reactivity or selectivity,connection to organometallic catalysis and the potential for making well-defined active sites[1-3].As catalytic active sites,oxide-supported isolated Pt-group metal atoms are well known for their unique reactivity and efficient metal utilization[4-6].Even continuous efforts have been made,it is still challenging to characterize the intrinsic ca-talytic activity of these dispersed active sites on oxide supports at a level that relates local electronic and geometric structure to function,because of their atomic dispersion,heterogeneity in the local coordination,dynamic changes in local coordination under reactive environments and low loading of metal[7-9]. 展开更多
关键词 relationship BETWEEN LOCAL coordination ISOLATED PT ATOMS Chemical Reactivity
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Exploration on the Characteristics and Important Relationships of Xi Jinping's New Concept of Coordinated Economic Development
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作者 Huang Shaoqin Sun Peng Wu Hao 《Contemporary Social Sciences》 2017年第4期96-108,共13页
During the 18 th CPC National Congress, Xi Jinping raised a series of economic development thoughts, namely the five new concepts of development; innovative, coordinated, green, open and shared development, and put fo... During the 18 th CPC National Congress, Xi Jinping raised a series of economic development thoughts, namely the five new concepts of development; innovative, coordinated, green, open and shared development, and put forward a series of economic development thoughts including"people-centered"economic development. These are the new summations of the practice of socialism with Chinese characteristics, and the latest achievements in the theory of the political economics of socialism with Chinese characteristics."People-centered"is both the starting point and final purpose of coordinated economic development, an accurate mastery of social and economic development rules, and also the foundation and specific manifestation of coordinated development between people and society. People's subjectivity, coordinated inclusiveness and dialectics of development are the characteristics of coordinated economic development. Regional coordinated development, urbanrural coordinated development, industrial coordinated development, coordinated development of national defense and economic construction, supply and demand coordinated development, ecological coordinated development and interacted coordinated development of the global economy are the important relationships of coordinated economic development that we have to recognize and handle properly. 展开更多
关键词 Xi Jinping’s new concept of coordinated development new feature important relationships
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Evolution of coordination between α and β phases for two-phase titanium alloy during hot working 被引量:14
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作者 Jian-wei XU Wei-dong ZENG +2 位作者 Da-di ZHOU Sheng-tong HE Run-chen JIA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第11期3428-3438,共11页
The evolution of coordination betweenαandβphases for a two-phase titanium alloy was investigated.For this purpose,hot compression and heat treatment under different conditions were carried out.The results show that ... The evolution of coordination betweenαandβphases for a two-phase titanium alloy was investigated.For this purpose,hot compression and heat treatment under different conditions were carried out.The results show that the ability of coordinated deformation betweenαandβphases can influence uniformity of microstructure evolution.Specifically,αphase maintains the lamellar structure andβphase has a low degree of recrystallization when the ability of coordinated deformation is good.In this case,αandβphases still maintain the BOR(Burgers orientation relationship),and their interface relationship is not destroyed even at large deformation.Both of the deformation extent ofαlamellae and recrystallization degree ofβphase increase with the decline of ability of coordinated deformation.Theαphase only maintains the BOR withβphase on one side,while the uncoordinated rotation with theβphase on the other side occurs within 10°.Theαandβphases rotate asynchronously when ability of coordinated deformation is poor.The degree of interface dislocation increases,andαandβphases deviate from the BOR. 展开更多
关键词 coordination ability titanium alloy orientation relationship globularization RECRYSTALLIZATION
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A Comprehensive Evaluation Framework of Water-Energy-Food System Coupling Coordination in the Yellow River Basin,China 被引量:9
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作者 YIN Dengyu YU Haochen +3 位作者 LU Yanqi ZHANG Jian LI Gensheng LI Xiaoshun 《Chinese Geographical Science》 SCIE CSCD 2023年第2期333-350,共18页
For mankind’s survival and development,water,energy,and food(WEF)are essential material guarantees.In China,however,the spatial distribution of WEF is seriously unbalanced and mismatched.Here,a collaborative governan... For mankind’s survival and development,water,energy,and food(WEF)are essential material guarantees.In China,however,the spatial distribution of WEF is seriously unbalanced and mismatched.Here,a collaborative governance mechanism that aims at nexus security needs to be urgently established.In this paper,the Yellow River Basin in China with a representative WEF system,was selected as a case.Firstly,a comprehensive framework for WEF coupling coordination was constructed,and the relationship and mechanism between them were analyzed theoretically.Then,we investigated the spatiotemporal characteristics and driving mechanisms of the coupling coordination degree(CCD)with a composite evaluation method,coupling coordination degree model,spatial statistical analysis,and multiscale geographic weighted regression.Finally,policy implications were discussed to promote the coordinated development of the WEF system.The results showed that:1)WEF subsystems showed a significant imbalance of spatial pattern and diversity in temporal changes;2)the CCD for the WEF system varied little and remained at moderate coordination.Areas with moderate coordination have increased,while areas with superior coordination and mild disorder have decreased.In addition,the spatial clustering phenomenon of the CCD was significant and showed obvious characteristics of polarization;and 3)the action of each factor is self-differentiated and regionally variable.For different factors,GDP per capita was of particular importance,which contributed most to the regional development’s coupling coordination.For different regions,GDP per capita,average yearly precipitation,population density,and urbanization rate exhibited differences in geographical gradients in an east-west direction.The conclusion can provide references for regional resource allocation and sustainable development by enhancing WEF system utilization efficiency. 展开更多
关键词 water-energy-food(WEF) comprehensive framework coupling coordination relationship driving mechanism Yellow River Basin China
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Inter-provincial pattern of the coupled and coordinated relationship between touristization and urbanization 被引量:2
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作者 LI Wei-wei CHEN Tian +1 位作者 MA Xiao-long YU Hu 《Ecological Economy》 2018年第2期82-92,共11页
The coordinated development between touristization and urbanization is the key to optimizing regional industrial structure and building a long-term dynamic mechanism for urbanization. Based on constructing the measure... The coordinated development between touristization and urbanization is the key to optimizing regional industrial structure and building a long-term dynamic mechanism for urbanization. Based on constructing the measurement index system of touristization and urbanization level, the evaluation model on the coupled and coordinated degree is used in this paper to measure the inter-provincial pattern of the coupled and coordinated relationship between touristization and urbanization in 31 provinces and autonomous regions in China. The results show that the coupled and coordinated relationship between touristization and urbanization is significantly different in different regions, which presents a gradient decline pattern of the highest in the east, the lower in the middle and the lowest in the west. In the future, measures should be taken to promote the coordinated development between touristization and urbanization in accordance with the regional differences and actual development needs. 展开更多
关键词 touristization URBANIZATION coupled and coordinated relationship inter-provincial pattern regional differences
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Coordination of economic development and ecological environment in resource exhausted cities
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作者 FANG Xing-cun CHEN Hao WANG Xiao-ling 《Ecological Economy》 2015年第1期36-42,共7页
This paper establishes the evaluation index system of ecological environment and economic development in resource exhausted cities, and calculates the level of economic development and ecological environment during th... This paper establishes the evaluation index system of ecological environment and economic development in resource exhausted cities, and calculates the level of economic development and ecological environment during the year 2005-2012 by using the entropy method. Furthermore, this study analyzes the coordination degree and coordinated development degree by using the coordination model. The results show that the coordination relationship of economic development and ecological environment continues to improve from 2005 to 2012 in most of these resource exhausted cities. By 2012, other resource depletion cities are in all kinds of hierarchical coordination except Yichun and Hegang. From the standpoint of coordination development degree, although most of these resource exhausted cities have been increased continuously but the level is also lower except in Tongling and Xinyu. Finally, this paper puts forward the corresponding countermeasures and suggestions according to the results of the analysis. 展开更多
关键词 RESOURCES EXHAUSTED CITIES economic development ECOLOGICAL environment coordinATED relationship
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Assessing the interaction of cross-city patient mobility and the coupling relationship between supply and demand of healthcare in China
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作者 XIANG Bowen WEI Wei +1 位作者 GUO Fang HONG Mengyao 《Journal of Geographical Sciences》 2025年第4期867-885,共19页
The uneven distribution of medical resources has led to increasingly frequent patient mobility;however, the interaction between this phenomenon and the healthcare supply-demand relationship remains underexplored. The ... The uneven distribution of medical resources has led to increasingly frequent patient mobility;however, the interaction between this phenomenon and the healthcare supply-demand relationship remains underexplored. The present study constructed the 2023Cross-City Patient Mobility Network in China using one million patient mobility data records obtained from online healthcare platforms. We applied urban network analysis to uncover mobility patterns and used the coupling coordination degree model to assess healthcare supply-demand relationships before and after patient mobility. Explainable machine learning further revealed the impact of supply-demand coupling on patient mobility. The results indicated the following: Patient mobility followed administrative boundaries, although megacities serve areas beyond provincial borders;The scale of healthcare supply and demand displayed a multi-centric spatial pattern with a general decline from east to west, and these characteristics of demand distribution were further solidified by patient mobility;Cities with low supply-demand coupling and undersupply experienced patient outflows, while cities with high coupling and oversupply attracted them. In turn, patient mobility helped balance healthcare supply and demand, optimising the coupling relationship across cities. Thus, this research not only provides a methodological reference for understanding the interaction between patient mobility and healthcare systems but also offers empirical insights for public health policy. 展开更多
关键词 cross-city patient mobility healthcare services coupling coordination degree model coupling relationship spatial analysis
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知识产权质押融资能否促进技术创新?——政策协调视角下的微观证据
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作者 刘大勇 徐源 +1 位作者 刘鑫 张俊艳 《天津大学学报(社会科学版)》 2026年第1期18-31,共14页
知识产权质押融资作为一种科技金融服务方式是基于知识产权资源的运营创新,为缓解企业融资压力、支持企业技术创新探索了可能方向,但目前对于其影响效果与作用方式的研究仍存在争论。对此,文章基于“政策协调”视角,结合政策匹配条件、... 知识产权质押融资作为一种科技金融服务方式是基于知识产权资源的运营创新,为缓解企业融资压力、支持企业技术创新探索了可能方向,但目前对于其影响效果与作用方式的研究仍存在争论。对此,文章基于“政策协调”视角,结合政策匹配条件、地区市场环境及企业自身的禀赋条件,以2011—2017年上市公司样本实证考察了知识产权质押融资对企业技术创新的影响及其作用条件。实证分析发现:地区知识产权质押融资规模及效率的提高促进了较小规模上市公司的创新,并对非国有企业的影响更加显著;当较小规模企业外部的金融服务条件更完善、配套补贴政策更充分时,知识产权质押融资对企业创新的促进作用会更强。研究结论表明,知识产权质押融资作为公共部门与市场合作的金融创新,有助于企业根据自身禀赋条件开展知识产权运营、提升创新优势,为地区更好发挥市场条件、优化资源配置提供有效路径。 展开更多
关键词 知识产权质押融资 创新绩效 政策协调 金融发展 政府与市场关系
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贸易政策不确定性感知与企业供应链非对称性配置:集中化和多元化视角
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作者 刘晨阳 赵子宜 《上海财经大学学报(哲学社会科学版)》 北大核心 2026年第1期51-65,112,共16页
在全球贸易政策不确定性日益上升的背景下,企业需要调整其供应链配置决策以规避风险保障经营,这既是企业供应链管理的重要内容,又是保障中国产业链供应链安全稳定、自主可控的微观基础。文章利用2008—2022年中国上市公司数据,采用文本... 在全球贸易政策不确定性日益上升的背景下,企业需要调整其供应链配置决策以规避风险保障经营,这既是企业供应链管理的重要内容,又是保障中国产业链供应链安全稳定、自主可控的微观基础。文章利用2008—2022年中国上市公司数据,采用文本分析法测算企业贸易政策不确定性感知,并检验企业供应链配置受贸易政策不确定性感知的影响。研究发现,企业感知贸易政策不确定性的上升推动供应链上游配置多元化、下游配置集中化,凸显对供应链上下游配置的非对称影响。影响机制分析发现,当供求协调成本越高、关系专用性投入越低、相对议价能力越低时,非对称效应会被放大。进一步分析发现,在合作关系黏性和供应链信息摩擦视角下,贸易政策不确定性感知对供应链上游配置的多元化效应在低市场化地区、高竞争行业、资源优势较高企业、高透明度企业以及本土企业中更显著;对下游配置的集中化效应在高市场化地区、高竞争行业、资源优势较低企业、低透明度企业以及非出口企业中更显著。文章为企业应对贸易政策不确定性风险,提升中国产业链供应链韧性、安全稳定和自主可控水平提供了经验证据和政策启示。 展开更多
关键词 贸易政策不确定性 供应链配置 非对称影响 供求协调成本 合作关系黏性
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技术创新驱动下双向产业转移协同的GVC攀升效应研究:倒U型关系识别与机制检验
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作者 张玉 寇明龙 《价格月刊》 北大核心 2026年第1期84-94,共11页
基于国际生产分割理论构建理论模型,采用1995—2020年经济合作与发展组织的TiVA数据库和中国制造业细分行业数据,实证考察双向产业转移协同对制造业全球价值链(GVC)地位升级的影响及作用机制。研究发现:第一,双向产业转移协同与制造业GV... 基于国际生产分割理论构建理论模型,采用1995—2020年经济合作与发展组织的TiVA数据库和中国制造业细分行业数据,实证考察双向产业转移协同对制造业全球价值链(GVC)地位升级的影响及作用机制。研究发现:第一,双向产业转移协同与制造业GVC地位呈现显著倒U型关系,初期协同效应显著促进GVC攀升,超过临界点后促进作用减弱甚至转为抑制。第二,技术创新是传导机制,通过平缓倒U型曲线的形态、右移拐点位置及提升曲线整体水平,缓解GVC升级的长期约束,驱动GVC地位螺旋式攀升。第三,中间产品转移与最终产品转移协同与制造业GVC地位均存在倒U型关系,但中间产品转移协同曲线更平缓;中高技术制造业较之于低技术制造业,通过产业转移协同实现GVC升级的峰值更高、战略空间更大。 展开更多
关键词 双向产业转移 协同技术创新 全球价值链地位 倒U型关系
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海岸带生态韧性与土地利用强度的时空关系及影响因素——以宁波市蟹钳港为例
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作者 应超 李加林 +4 位作者 刘永超 陈宇昕 曹罗丹 田鹏 陈璐怡 《生态学报》 北大核心 2026年第2期753-770,共18页
生态韧性为海岸带生态系统应对内外风险扰动提供了全新思路,准确识别生态韧性与土地利用强度的时空关系,对推动海岸带可持续发展具有重要意义。构建抵抗力-适应力-恢复力生态韧性评价模型和土地利用强度模型,分析了2000—2022年蟹钳港... 生态韧性为海岸带生态系统应对内外风险扰动提供了全新思路,准确识别生态韧性与土地利用强度的时空关系,对推动海岸带可持续发展具有重要意义。构建抵抗力-适应力-恢复力生态韧性评价模型和土地利用强度模型,分析了2000—2022年蟹钳港生态韧性与土地利用强度的时空演变格局,基于双变量空间自相关和耦合协调模型探究分析两者的时空关系,最后基于地理探测器探测两者耦合协调的影响因素。结果表明:(1)2000—2022年生态韧性呈现波动下降的变化趋势,生态系统抵抗力除2005—2010年外,其余年份均不断下降,生态系统适应力略微波动上升,生态系统恢复力先上升后下降;(2)2000—2022年蟹钳港土地利用强度先下降后不断上升,以低等级强度和中等等级强度为主;(3)2000—2022年蟹钳港生态韧性与土地利用强度呈现显著负相关,处于初级协调阶段,耦合协调水平较高;(4)地形和坡度是影响生态韧性与土地利用强度耦合协调的主导因素,社会经济因素的影响程度快速增长,交互探测以双因子增强作用为主。 展开更多
关键词 生态韧性 土地利用强度 时空关系 耦合协调 影响因素 蟹钳港
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入境旅游与区域经济耦合协调发展——基于云南省的案例研究
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作者 樊艳翔 贺灿飞 +1 位作者 李文韬 赵筱青 《北京大学学报(自然科学版)》 北大核心 2026年第1期132-146,共15页
以云南省为研究对象,使用耦合协调度模型、自然间断点分级法、核密度估计和Dagum基尼系数法,探究入境旅游与区域经济的耦合协调特征的时空格局与差异。在此基础上,使用随机森林回归模型,分别识别影响云南省入境旅游、区域经济以及入境... 以云南省为研究对象,使用耦合协调度模型、自然间断点分级法、核密度估计和Dagum基尼系数法,探究入境旅游与区域经济的耦合协调特征的时空格局与差异。在此基础上,使用随机森林回归模型,分别识别影响云南省入境旅游、区域经济以及入境旅游与区域经济耦合协调发展水平的主导因素。研究结果表明,云南省各城市入境旅游与区域经济耦合协调发展水平整体上不断提升,向更高水平的协调发展状态跃进,但区域发展空间不均衡性突出;旅游财政支持力度、产业结构优化、交通运输水平、旅游资源丰富度、旅游设施丰富度、商业活动氛围和科技研发水平是影响云南省入境旅游与区域经济耦合协调发展的主导因素。 展开更多
关键词 云南省 入境旅游 区域经济 耦合协调关系 影响机制
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江苏省传统村落空间分异特征及其与乡村振兴水平的关系
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作者 曹卢予 丁杨 +4 位作者 徐鹤怡 戴悦 郝星源 钱蜜 柳玉梅 《智慧农业导刊》 2026年第2期31-34,39,共5页
传统村落是承载乡村历史与文化的“活化石”。党的二十大报告强调,应传承中华优秀传统文化,提升国家文化软实力和中华文化影响力。江苏省已认定省级传统村落554个,乡村振兴战略也为其发展提供全新的视野。该研究以江苏省为例,综合运用... 传统村落是承载乡村历史与文化的“活化石”。党的二十大报告强调,应传承中华优秀传统文化,提升国家文化软实力和中华文化影响力。江苏省已认定省级传统村落554个,乡村振兴战略也为其发展提供全新的视野。该研究以江苏省为例,综合运用空间分析与数理统计方法,系统探究传统村落和乡村振兴水平之间的内在关联,以期为该地区乡村文化保护和全面振兴提供理论依据与实践参考。 展开更多
关键词 乡村振兴 传统村落 耦合协调模型 空间分异 量化关系
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京津冀生态系统服务供需匹配与耦合协调时空演进及驱动因素
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作者 韩宇 刘佳铭 +1 位作者 董振林 温亚利 《中国环境管理》 2026年第1期114-127,共14页
本文在定量评估京津冀生态系统服务供需的基础上,利用耦合协调度模型揭示生态系统服务供需的耦合协调时空演变特征,进一步利用地理加权回归探究其驱动因素,以期为区域生态安全格局构建与高质量协同发展提供科学依据。结果表明:①研究期... 本文在定量评估京津冀生态系统服务供需的基础上,利用耦合协调度模型揭示生态系统服务供需的耦合协调时空演变特征,进一步利用地理加权回归探究其驱动因素,以期为区域生态安全格局构建与高质量协同发展提供科学依据。结果表明:①研究期间,京津冀生态系统服务供给与需求总体呈上升趋势,空间格局呈现“西北高、东南低”的特征,而需求空间分布总体与供给相反,呈“西北低、东南高”的分布特征。②京津冀生态系统服务供需耦合协调度整体处于中度失调状态,其空间分布以中度失调区为主。③NPP、地形起伏度、降水量与GDP对耦合协调度主要表现为正向驱动作用,而气温和路网密度主要呈负向驱动效应。研究表明,京津冀生态系统服务供需存在明显的空间错配现象,据此提出差异化生态管控策略,可为区域生态管理的精准施策提供参考依据。 展开更多
关键词 生态系统服务 重心迁移 供需关系 耦合协调 京津冀
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基于SSR标记的浙江省地方玉米种质遗传关系分析
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作者 何苏悦 李燕 +3 位作者 丁云倩 李欣泽 韩庆辉 陈小央 《浙江农业学报》 北大核心 2026年第1期24-34,共11页
为探究浙江省地方玉米种质的遗传基础与亲缘关系,本研究利用40对简单重复序列(simple sequence repeat,SSR)标记对来自浙江省的259份地方玉米种质进行了遗传多样性分析。结果表明,40对SSR标记引物共检测出399个等位变异,每对引物检测到... 为探究浙江省地方玉米种质的遗传基础与亲缘关系,本研究利用40对简单重复序列(simple sequence repeat,SSR)标记对来自浙江省的259份地方玉米种质进行了遗传多样性分析。结果表明,40对SSR标记引物共检测出399个等位变异,每对引物检测到的等位基因变异数为4~22个,平均为9.975个;有效等位基因数范围为0.8185~1.0000,平均为0.9822;基因多样性指数范围为0.3036~0.9033,平均为0.7171;多态信息含量范围为0.2890~0.8954,平均为0.6868;Shannon指数范围为0.655~2.527,平均值为1.615。通过UPGMA聚类分析,将259份地方玉米种质划分为3个类群,第Ⅰ类群包含72份种质,占27.8%;第Ⅱ类群包含72份种质,占27.8%;第Ⅲ类群包含115份种质,占44.4%。主坐标分析表明,类群内个体距离较近,类群间距离大且无重叠,进一步证实聚类分析结果的可靠性。综上所述,浙江省地方玉米种质在育种实践过程中形成了相对独立的优势类群,遗传多样性丰富,可为玉米优异基因挖掘、优异种质创制和新品种培育奠定基础。 展开更多
关键词 玉米 简单重复序列(SSR)标记 聚类分析 主坐标分析 遗传关系 地方种质
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门式刚架结构在物流仓库中的设计与应用研究
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作者 文坤 《科技资讯》 2026年第6期140-142,共3页
门式刚架结构在物流仓库中的应用非常广泛。本文以某单层仓储物流仓库为例,开展了门式刚架结构的设计与应用研究。为保证构件的整体稳定和局部稳定,考虑了构件的长细比和宽厚比,同时兼顾了钢柱与钢梁高度的协调关系,依次设计了钢梁、钢... 门式刚架结构在物流仓库中的应用非常广泛。本文以某单层仓储物流仓库为例,开展了门式刚架结构的设计与应用研究。为保证构件的整体稳定和局部稳定,考虑了构件的长细比和宽厚比,同时兼顾了钢柱与钢梁高度的协调关系,依次设计了钢梁、钢柱、平板式铰接柱脚、支撑系统、屋面檩条与墙梁,同时提出了防火设计要求。本物流仓库项目已完成竣工验收,其经济性良好、结构安全可靠,满足现场使用需求。 展开更多
关键词 门式刚架 物流仓库 整体稳定 局部稳定 协调关系 结构安全
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面向陆海统筹的广东省海洋地理实体构建与分析
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作者 李姗迟 《地理空间信息》 2026年第1期21-25,共5页
地理实体是新型基础测绘的重要工作对象和研究视角,但在海洋领域的研究较少。为实现陆海统筹的数据应用,利用与陆上地理实体兼容的资源描述框架,通过实体识别、特征提取、关系分析等技术从数据模型设计层面实现了海洋地理信息的实体化,... 地理实体是新型基础测绘的重要工作对象和研究视角,但在海洋领域的研究较少。为实现陆海统筹的数据应用,利用与陆上地理实体兼容的资源描述框架,通过实体识别、特征提取、关系分析等技术从数据模型设计层面实现了海洋地理信息的实体化,从而为用户提供了轻量化、陆海一体的地理知识服务。研究成果已应用于广东省海域海岛管理,利用海域海岛地名普查、海域动态监视监测等数据构建海洋地理实体,从而实现海岛档案管理与检索、海洋产业发展趋势分析、用岛项目规划选址和海洋监管重点区域识别等应用。 展开更多
关键词 海洋地理实体 资源描述框架 关联关系 知识服务 陆海统筹
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Coordinated development of land multi-function space: An analytical framework for matching the supply of resources and environment with the use of land space for ecological protection, agricultural production and urban construction 被引量:5
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作者 QU Yanbo ZHANG Yanjun +3 位作者 WANG Shilei SHANG Ran ZONG Haining ZHAN Lingyun 《Journal of Geographical Sciences》 SCIE CSCD 2023年第2期311-339,共29页
Based on the carrying capacity of the resources and the environment,this article defines the connotation of the land multifunctional space(LMFS)from three aspects,ecological protection,agricultural production and urba... Based on the carrying capacity of the resources and the environment,this article defines the connotation of the land multifunctional space(LMFS)from three aspects,ecological protection,agricultural production and urban construction,in the new era of land space planning system.Moreover,a framework is constructed for the coordinated development of the multi-functional oriented space to match the use of land space(ULS)with the supply of resources and environment(SRE).Based on this,the technology and methods of comprehensive evaluation,dominance recognition,and matching relationship division functions of the use of land space(FULS)and functions of the supply of resources and environment(FSRE)are discussed.The advantageous functions of the use of land space(AFULS)and advantageous functions of the supply of resources and environment(AFSRE)are also identified in the study area.A LMFS coordinated development system integrating“function position-comprehensive partition-regulation strategy”is proposed.Through the empirical study of Shandong province,we found that,first,the FULS of ecological protection space in the province is mainly found in high value areas,and the FSRE is mainly in low value areas,which has certain complementarity in the space.The FULS of agricultural production space is mainly observed in high value areas,the FSRE is mainly in middle value areas,and the spatial distribution is balanced and staggered.The FULS of the urban construction space and the FSRE are mainly in middle values areas,and the spatial distribution is basically similar.Second,the FULS in the study area is dominated by the single advantage of agricultural production and urban construction,while the FSRE has a relatively balanced distribution of the advantages of ecological protection,single agricultural production and compound advantages of agricultural production and urban construction,and urban construction and ecological protection.The matching between the two is mainly at high and middle levels.Specifically,70%of the province’s land space still has a certain development and utilization potential,and 30%of ULS intensity is close to or exceeds the resource and environment carrying capacity.Third,considering the comprehensive impact of resource endowment,social and economic development and policy and institutional environment on different matching relationships,this paper constructs the land spatial development strategic pattern of“two screens-seven regions-multicore”positioning and“four regions-eight categories”hierarchical area of Shandong at the macro level,and puts forward a differentiated land space development strategy. 展开更多
关键词 land space coordinated development DOMINANCE matching relationship ecological protection agricultural production urban construction Shandong province
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