东北地区城乡一体化进程评估   总被引：39，自引：7，他引：32  

修春亮  许大明  祝翔凌 《地理科学》2004,24(3):320-325

对东北区内部的沿海大城市地区、中部大城市地区和西部中等城市地区,分别选取大连、长春和白城作为调查对象,分析各典型城市地区的城乡一体化进程。主要以现状行政区划的市区代表城市地域,市区外围的县(县级市)和个别远郊区代表乡村地域,以乡镇为研究单元,采用综合指数法评价城乡一体化的进程。城乡一体化综合指数由经济发展水平、农村非农化水平、社会公平和福利、交通及日常联系等方面的相对指标构成,通过乡村各微观地域(乡镇、县)各项指标与中心城市的比值加权求和而得。综合指数计算并结合实地考察的初步结论是：各地区城乡联系逐步加强并趋于多样化,围绕中心城市的外围地域已经形成了包括高度一体化地域(一级)、中度一体化地域(二级)、初级一体化地域(三级)、传统农村地域(四级)在内的空间序列,其中大连地区4个级别的一体化地域序列完整,高度一体化地域已经形成并逐步扩大,城乡关系趋于逐步融合;长春地区缺失第一级,白城地区只有第三、四级,城乡二元结构仍然明显。  相似文献   

郯庐断裂带苏皖段及邻区b值时空特征研究     

余腾  王鑫  李明峰  朱益民  孙小荣 《大地测量与地球动力学》2021,41(2):173-179

采用郯庐断裂带苏皖段及邻区近50 a的地震数据,在定量分析区域最小完备震级M_C和推导b值计算的极大似然法基础上,重点研究G-R关系,尤其是b值时空分布演化特征,并依据b值指示意义进行5级以上地震关联性和断裂带影响区域的构造应力分布状况分析。结果显示,依据b值的时间分布特征,研究区中强地震发生时段与中短期b值下降时段关联率达到80％以上;依据b值的空间分布特征,研究区苏北盆地整体及以南和合肥盆地南缘范围内的地壳应力较高,与超高压变质带的分布有较好的一致性,结合相关地质资料认为,该区域处于孕震阶段。  相似文献   

碳纤维布加固钢筋混凝土柱的剪力-位移关系及其破坏位移增大系数分析     

吴波  王维俊  王帆 《地震工程与工程振动》2004,24(5):141-148

编制了碳纤维布加固钢筋混凝土柱的剪力-位移关系全过程分析程序,通过对多种工况下碳纤维布加固钢筋混凝土柱的剪力-位移关系进行大量计算分析,较全面地探讨了碳纤维布配箍特征值、轴压比、剪跨比、箍筋配箍特征值、纵筋配筋率、混凝土强度等参数对碳纤维布加固钢筋混凝土柱的剪力-位移关系及其破坏位移增大系数的影响。在此基础上,给出了碳纤维布加固钢筋混凝土柱破坏位移增大系数的回归计算公式,统计建立了碳纤维布加固钢筋混凝土柱的剪力-位移关系三折线模型中各无量纲特征参数的确定方法。  相似文献   

城市用地功能精细化识别方法：时序动态图嵌入深度学习模型     

高原  王洁  李钢  颜建强 《地球信息科学学报》2022,24(10):1968-1981

多源大数据融合背景下的城市功能区识别是复杂非线性系统的模式识别问题,如何有效地从大规模的轨迹数据中提取出多粒度连续性时变和多尺度空间相互作用的信息是进行城市区域功能识别的关键。本研究设计实现了一种基于时序动态图嵌入的深度学习模型,在融合滴滴出行及兴趣点数据（Point of Interest, POI）基础上,提取城市区域存在的时间和空间上的隐式特征,结合聚类分析实现城市用地功能的语义识别。结果表明,成都市中心的用地功能趋向复合多样化的发展,且用地属性随时间发生作用范围和用地类型的变化,呈现出功能随着城市群体活动而变化的时空规律。与相关文献的对比实验表明,本文提出方法在更细粒度的时间段下进行功能区识别,得到的同一类功能区域内集聚度更高,能够更好的捕获复合型区域在不同时间模式下呈现出的用地功能变化。本研究为城市用地功能识别研究提供了新的技术方法,为城市规划研究人员全面理解城区结构属性提供了有效手段,对推动城市空间得到更合理高效的利用具有一定的价值。  相似文献   

国家资源环境安全要素的综合评价   总被引：5，自引：0，他引：5  

张雷 《地球信息科学学报》2002,4(4):86-92

资源环境安全问题始终是世界各国持续发展的核心任务和基本需求。考虑到单要素和整体两大分析方法的不足 ,作者提出了一种具有针对性的要素综合分析方法。根据世界 10个人口 1亿以上国家的抽样分析表明 ,土地、水资源、矿产及生态环境的整体状态是决定国家资源环境安全的基本要素群体。与此同时 ,为了改善国家 ,特别是发展中国家的资源环境脆弱状态和提高其稳定程度 ,第一是严格控制人口增长 ;第二是努力推进本国资源环境开发的国际化进程 ;第三是增大智力投入以提高资源深化加工程度 ;第四是加大本国生态环境保护力度。  相似文献   

THE URBAN FUNCTION OF SUZHOU ON BASIS OF THE SHANGHAI-SUZHOU RELATIONSHIP   总被引：1，自引：0，他引：1  

ZOU Jun  ZHANG Lu  CHEN Min-qi  ZHANG Jing-xiang 《中国地理科学(英文版)》2001,11(3):233-240

１ＩＮＴＲＯＤＵＣＴＩＯＮＷｉｔｈｔｈｅａｃｃｅｌｅｒａｔｉｏｎｏｆｔｈｅｅｃｏｎｏｍｉｃｇｌｏｂａｌｉｚａ-ｔｉｏｎｔｈｅｇｒａｄｕａｌｓｈａｐｉｎｇｏｆｔｈｅｎｅｗｉｎｔｅｒｎａｔｉｏｎａｌｄｉｖｉ-ｓｉｏｎｏｆｌａｂｏｒａｎｄｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｔｈｅｔｒａｎｓｎａｔｉｏｎａｌｃｏｒｐｏｒａｔｉｏｎｓｔｈｅｗｏｒｌｄｕｒｂａｎｓｙｓｔｅｍｓｈａｖｅｂｅｇｕｎａｎｅｗｒｏｕｎｄｏｆｉｎｔｅｇｒａｔｉｏｎ．Ｏｎｏｎｅｈａｎｄｔｈｅｃｉｔｉｅｓａｌｌｏｖｅｒｔｈｅｇｌｏｂｅａｒｅ…  相似文献   

A THEORETICAL DISCUSSION ON TYPES AND MEASUREMENT OF SUSTAINABLE DEVELOPMENT     

Qing-min Meng  Guo-ping Li 《中国地理科学(英文版)》2001,11(3):201-210

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｃｏｒｅｏｆｇｅｏｇｒａｐｈｉｃａｌｓｔｕｄｉｅｓｔｈｅａｒｅａｌｓｙｓｔｅｍｏｆｍａｎｌａｎｄｒｅｌａｔｉｏｎｓｈｉｐＷＵ１９９１ｉｓｔｈｅｓｔａｒｔｉｎｇｐｏｉｎｔｏｆｓｔｕｄｙｉｎｇｒｅｇｉｏｎａｌｓｕｓｔａｉｎａｂｌｅｄｅｖｅｌｏｐｍｅｎｔ．Ｆｒｏｍｔｈｅｐｏｉｎｔｏｆｓｕｓｔａｉｎａｂｌｅｄｅｖｅｌｏｐｍｅｎｔｔｈｅｃｏｏｒｄｉ-ｎａｔｉｏｎｏｆｍａｎｌａｎｄｒｅｌａｔｉｏｎｓｈｉｐｉｓｄｅｖｅｌｏｐｍｅｎｔｓｕｓｔａｉｎ-ａｂｉｌｉｔｙ．…  相似文献   

Cloud Condensation Nuclei over the Bay of Bengal during the Indian Summer Monsoon     

D.M.CHATE  R.T.WAGHMARE  C.K.JENA  V.GOPALAKRISHNAN  P.MURUGAVEL  Sachin D.GHUDE  Rachana KULKARNI  P.C.S.DEVARA 《大气科学进展》2018,35(2):218-223

The first measurements of cloud condensation nuclei(CCN) at five supersaturations were carried out onboard the research vessel "Sagar Kanya"(cruise SK-296) from the south to the head-bay of the Bay of Bengal as part of the Continental Tropical Convergence Zone(CTCZ) Project during the Indian summer monsoon of 2012. In this paper, we assess the diurnal variation in CCN distributions at supersaturations from 0.2% to 1%(in steps of 0.2%) and the power-law fit at supersaturation of 1%.The diurnal pattern shows peaks in CCN concentration(NCCN) at supersaturations from 0.2% to 1% between 0600 and 0700 LST(local standard time, UTC+0530), with relatively low concentrations between 1200 and 1400 LST, followed by a peak at around 1800 LST. The power-law fit for the CCN distribution at different supersaturation levels relates the empirical exponent(k) of supersaturation(%) and the NCCNat a supersaturation of 1%. The NCCNat a supersaturation of 0.4% is observed to vary from 702 cm~(-3) to 1289 cm~(-3), with a mean of 961 ± 161 cm~(-3)(95% confidence interval), representing the CCN activity of marine air masses. Whereas, the mean NCCNof 1628 ± 193 cm~(-3) at a supersaturation of 1% is higher than anticipated for the marine background. When the number of CCN spectra is 1293, the value of k is 0.57 ± 0.03(99% confidence interval)and its probability distribution shows cumulative counts significant at k ≈ 0.55 ± 0.25. The results are found to be better at representing the features of the marine environment(103 cm~(-3) and k ≈ 0.5) and useful for validating CCN closure studies for Indian sea regions.  相似文献   

Analysis of the coupled relationship between grain yields and agricultural labor changes in China   总被引：3，自引：0，他引：3  

Dazhuan Ge  Hualou Long  Yingnan Zhang  Shuangshuang Tu 《地理学报(英文版)》2018,28(1):93-108

In this paper we establish a model that expresses the coupled relationship between grain yield and agricultural labor changes in China, and present a preliminary discussion of the coupled processes involved in changes in these factors at the county level. Thus, we develop two coefficients on the basis of county-level statistical data for grain yield and agricultural labor for the years 1991, 2000, and 2010, namely, the grain-labor elasticity coefficient (GLEC) and the agricultural labor-transfer effect coefficient (ALTEC). The results of this study show that during the transformation process of agricultural development in China, different kinds of coupled relationships between grain yield and agricultural labor changes co-existed at the same time. For example, between 1991 and 2010, counties characterized by three different coupled modes (i.e., increasing grain yield and decreasing agricultural labor, increasing grain yield and agricultural labor, and decreasing grain yield and agricultural labor) account for 48.85%, 29.11%, and 19.74% of the total across the study area, respectively. Interestingly, a coupled relationship between increasing grain yield and decreasing agricultural labor is mainly concentrated in the traditional farming areas of China, while a coupled relationship between increasing grain yield and agricultural labor is primarily concentrated in pastoral areas and agro-pastoral ecotones in underdeveloped western China. At the same time, a coupled relationship between decreasing grain yield and agricultural labor is concentrated in areas that have experienced a rapid development transition in agriculture, especially the developed southeastern coast of China. The results of this study also show that between 1991 and 2010, 1961 counties experienced a decline in the proportion of agricultural labor; of these, 1452 are also characterized by increasing grain yield, 72.38% of the total. This coupled relationship between grain yield and changes in the proportion of agricultural labor shows a stepped fluctuation and has continually strengthened over time. Data show that mean values for the GLEC and ALTEC increased from–0.25 and–2.93 between 1991 and 2000 to–0.16 and–1.78 between 2000 and 2010, respectively. These changes in GLEC and ALTEC illustrate that the influence of agricultural labor changes on increasing grain yields has gradually diminished. Finally, the results of this study reveal that the ‘Hu Huanyong Line’ is a significant boundary sub-dividing this coupled relationship between grain yield and changes in agricultural labor.  相似文献   

The trade network of the Belt and Road Initiative and its topological relationship to the global trade network   总被引：2，自引：0，他引：2  

Zhouying Song  Shuyun Che  Yu Yang 《地理学报(英文版)》2018,28(9):1249-1262

Unimpeded trade is one of the cooperation priorities in the Belt and Road Initiative proposed by China. On 15 May 2017, the Joint Communique of the Leaders Roundtable of the Belt and Road Forum for International Cooperation reaffirmed the participants’ shared commitment to build an open economy and ensure free and inclusive trade. The Belt and Road Initiative (BRI) is not only China's new action to drive its open and global development, but also a platform for an increasing number of countries to explore free and inclusive trade and promote a universal, rule-based, open, non-discriminatory, and equitable multilateral trade system. It is therefore important to examine the topological relationship between the BRI and global trade networks. More specifically, this article first analyzes the community structure of trade networks using a community detection algorithm, and then estimates the topological relationship between different trade communities. The findings of this article are as follows. First, this research identified three trade communities and two sub-communities in the BRI trade network, in which China is the core, Russia is the sub-core of the biggest trade community, and India, United Arab Emirates, and Saudi Arabia are cores of the second trade community (South Asia-West Asia). Second, it identified five trade communities in the global trade network, centred on China, USA, Russia, India-United Arab Emirates, and Germany- Netherlands-France-Britain and other European developed countries. Third, the topological analysis indicated that in the global trade network, most BRI countries are attracted by the core nodes of the BRI regions, such as the China, Russia and India-United Arab Emirates core nodes, and have strong trade contacts with BRI countries. Most Central-East European countries are mainly attracted by Germany-Netherlands-France-Britain and other developed European countries with a low penetration of BRI trade. Although some Southeast Asian countries are incorporated into the Asia-Australia-South Africa community with China as the core, they still need to strengthen trade linkages with BRI countries.  相似文献