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101.
THE URBAN FUNCTION OF SUZHOU ON BASIS OF THE SHANGHAI-SUZHOU RELATIONSHIP   总被引:1,自引:0,他引:1  
1INTRODUCTIONWiththeaccelerationoftheeconomicglobaliza-tionthegradualshapingofthenewinternationaldivi-sionoflaborandthedevelopmentofthetransnationalcorporationstheworldurbansystemshavebegunanewroundofintegration.Ononehandthecitiesallovertheglobeare…  相似文献   
102.
1INTRODUCTIONThecoreofgeographicalstudiesthearealsystemofmanlandrelationshipWU1991isthestartingpointofstudyingregionalsustainabledevelopment.Fromthepointofsustainabledevelopmentthecoordi-nationofmanlandrelationshipisdevelopmentsustain-ability.…  相似文献   
103.
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   
104.
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   
105.
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   
106.
中国人地关系及人地关系地域系统研究方法述评   总被引:4,自引:0,他引:4  
李扬  汤青 《地理研究》2018,37(8):1655-1670
人地关系及人地关系地域系统是地理学基础理论研究的本质所在,其研究方法的发展和完善不仅能促进人地关系研究的不断深化,而且可以更有效地解决经济社会发展中出现的复杂资源环境问题。在梳理人地关系及人地关系地域系统的内涵及研究脉络基础上,从哲学和环境史、可持续发展、人地关系地域系统研究方法、人地关系综合表征方法等四方面评述了中国人地关系及人地关系地域系统的研究方法,并提出了未来的发展趋势。① 伴随着人地关系及人地关系地域系统内涵的不断演变,人地关系地域系统的研究方法也不断发展,丰富了人地关系的理论内涵和方法体系。② 人地关系地域系统的不同研究方法各具特点,并且各有其适用性和局限性,总体上是往综合集成方向发展,如生态足迹和资源环境承载力等,是人地关系综合集成研究的有益探索。③ 提出人地关系地域系统研究方法未来的发展趋势包括发展自然要素和人文要素耦合的综合集成研究方法,加强新技术手段和新研究方法的运用,完善资源环境基础和资源环境承载力等综合研究的理论体系。  相似文献   
107.
都市区空间结构与经济发展的互动关系研究   总被引:5,自引:3,他引:2  
张婷麟  孙斌栋 《地理科学》2017,37(4):512-518
文章采用结构方程模型实证检验空间结构与经济发展的互动关系。研究发现,中国都市区已经进入多中心分散阶段,空间结构与经济发展存在因果关系,即经济发展水平的提高会扩大人口规模,规模增加则导致集聚不经济上升,并促进空间结构多中心化。多中心化后的空间结构由于降低了集聚不经济而进一步提高生产率。因而,传统地理学中关于两者互动发展的描述得到实证支持;同时明确了多中心化的直接动力是人口规模的增加,而不是经济发展水平的提高。这些发现对于优化当前中国的城市与区域空间战略具有重要的启示。  相似文献   
108.
人海关系地域系统的构成及其研究重点探讨   总被引:3,自引:1,他引:2  
刘天宝  韩增林  彭飞 《地理科学》2017,37(10):1527-1534
在全球化和人类活动向海洋扩张的背景下,作为总体性人地关系一个组成部分的人海关系正变得日益复杂和重要,亟需对其进行基础性的理论解读,以整合和指导具体研究的展开。人海关系地域系统包括人类、海洋和陆地3个基本组成部分。其中,人类具有自然和社会2种基本属性,受人类活动影响的海洋和陆地具有自然、社会和关系3种基本属性。人类与海洋、人类与陆地和海洋与陆地之间的互动构成了人海关系地域系统中最基本的相互关系,其不同组合和演变塑造出了具体、多样的人海关系地域系统。当前人海关系地域系统的研究重点包括海洋观、海洋的开发与保护、国际海洋关系、陆海统筹和海洋社会5个方面。  相似文献   
109.
To investigate the static and dynamic resilient modulus of fine soil, and adapting to the new design code and maintenance system of highway subgrade in China, a series of static and dynamic tests were carried out according to the standard laboratory test methods (JTG E40-2007 and JTG D30-2015, respectively). The effects of initial water content, compactness and freeze-thaw cycles on the static and dynamic resilient moduli of fine soil were investigated and analyzed. Experimental test results show that with increasing water content, dry density and freeze-thaw cycles, the static moduli reduces about 10.2%~40.0%, 14.4%~45.5%, and 24.0%~50.3%, and dynamic moduli reduces about 10.9%~90.8%, 2.5%~38.4%, and 0.0%~46.0%, respectively. Then, the empirical mathematical relationship between static and dynamic resilient moduli was established under different water content, dry density and freeze-thaw cycles. The investigation results can be used to determine the dynamic modulus of fine soil by widely used static modulus, which could meet the requirement of adopting dynamic modulus index in new specification.  相似文献   
110.
空间对准是最基本的空间排列形式之一,属于高层次的空间关系概念。根据Gestalt心理学的空间认知原理,提出空间对准的概念及其定量描述和计算方法。通过定义正对投影长度比,实现空间对准的定量描述与计算,表明其具有平移、旋转、尺度不变性,弱反身性,不可传递性等。通过模拟实验分析和城市双线道路识别与建筑群直线模式识别两个真实案例,证明文中方法的实用性和有效性。  相似文献   
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