基于势能联系模型的区域潜在经济关系研究

在区域一体化背景下,基于资金流通、产业发展、劳动力供给和交通信息4个维度构建指标体系,运用势能联系模型测度2007―2017年长三角潜在经济关系,并从空间格局和网络特征双重视角对测度结果进行深度分析。主要得出如下结论：① 长三角潜在经济关系上升态势明显,空间上表现为典型的“三圈层”结构特征;② 潜在经济关系总体上呈现极化趋势,上海与其他3省域潜在经济关系的基尼系数下降明显,但苏浙皖之间的基尼系数仍在上升;③ 潜在经济关系的点度中心性和中介中心性均呈上升态势,潜在经济关系网络表现为明显的4类凝聚子群结构;④ 长三角经济合作潜力格局呈现空间马太效应,少数城市表现出异质性特征。根据研究结论提出政策建议：优化长三角空间一体化格局,权衡区内与区外经济联系,强化合作潜力大的城市之间的经济联系,完善一体化运行的体制机制。     

China＇s regional transport dominance： Density, proximity, and accessibility

Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects: quality, quantity, and advantage, measured by density, proximity, and accessibility indices. County is the basic unit for analysis. The results reveal: (1) Transport dominance statistically follows a partial normal distribution. A very few counties, 1.4% of the total, have extremely high transport dominance which strongly supports the socio-economic development in these areas. In contrast, one eighth of all counties have poor transport dominance which impedes local socio-economic development to some extent. The remaining areas, about 70% of the counties, have median transport dominance. (2) Transport dominance is spatially unevenly distributed, with values decreasing gradually from the coastal area to the inland area. Areas in the first-highest level of transport dominance are mainly concentrated in the Yangtze River Delta, the Greater Beijing area, and the Pearl River Delta. Areas in the second-highest level are focused in Chengdu, Chongqing, and Wuhan metropolitan areas. Provincial capitals and a few other counties belong to the third-highest level.     

济阳坳陷青东凹陷低熟油生烃机理研究

青东凹陷勘探程度低,油气资源潜力尚未得到充分认识,开展凹陷内低熟油成因机理的研究有利于评价油气资源潜力并指导油气勘探工作。原油的物理及地球化学特征表明低熟油主要分布于凹陷边缘的沙四上亚段储层中。油源对比显示低熟油主要来自凹陷内沙四上亚段低熟烃源岩。研究区沙四段烃源岩具备形成低熟油的地质和地球化学条件：沙四段泥页岩有机质丰度高,有机质类型以腐泥型(I)和腐泥-腐殖型(II1)为主;泥页岩与蒸发岩共生的咸化还原环境因富含高矿化度地层水而有助于有机质早期转化生烃;烃源岩中的可溶有机质经过低温化学反应、细菌活动、生物催化作用等可形成低熟油。该研究对青东凹陷油气勘探工作有重要指导意义,寻找低熟油气藏是研究区未来重要的勘探方向。     

港口体系转型的空间格局及影响因素——基于长江三角洲实证分析

采用"理论演绎-案例实证-机理阐释"的研究逻辑,从空间视角提出理论假设,分析港口体系在运量、航线与后勤3个维度的集散及转型规律,并以长三角集装箱港口体系为例进行假设验证.结果 表明,运量和航线总体上表现为空间分散化态势,低端后勤要素亦由中心枢纽港城市向外围边缘港城市扩散,但高端后勤要素在空间上呈现出进一步向中心枢纽港城...     

FASTL波段多波束馈源设计的初步分析

把抛物面天线的偏焦理论应用于FASTL波段多波束馈源系统的设计,分析了馈源喇叭横向偏焦距离与相应波束偏离角之间的关系,结合多波束射电望远镜扫描方式的要求,给出了FASTL波段多波束馈源的工作带宽、多波束馈源中相邻喇叭的间距以及喇叭口径大小的限制,并对正六边形阵列中处于不同位置的喇叭对应的波束的主瓣情况作了详细计算和分析。由此说明了FASTL波段多波束馈源采用19波束的可行性。另一方面,根据得到的工作频率带宽和喇叭口径大小的情况,对OMT和喇叭类型的选择进行了探讨。本文给出了FASTL波段多波束系统的大概轮廓,为进一步精确设计指明了方向。     

中国交通流的衰减函数模拟及特征

交通流具有随距离延伸而不断衰减的空间属性,距离衰减规律是交通地理学的重要议题.基于空间"流"距离衰减研究进展的评述,本文构筑了交通流距离衰减规律的主要可能函数模型.包括指数模型、Pareto模型、常对数模型、平方指数模型、开方指数模型,采用中国城际交通流包括公路客流、铁路客流、铁路货流和航空客流,分别对5种距离衰减模型进行了模拟并对比分析,从中识别出最佳的距离衰减函数是Pareto模型.然后,重点分析了各种交通流距离衰减函数的参数差异和地理内涵,并采用时间序列的交通流进行模拟,考察距离衰减函数的主要参数变化,并解释其地理内涵,同时绘制了交通流累计率曲线和分配率曲线,对各种交通方式的距离衰减函数模型、主要函数参数和距离衰减规律进行论证和解释.     

我国人文与经济地理学发展回顾与展望——变化大背景下我国人文与经济地理学发展高层论坛综述

2016年1月22-23日,“变化大背景下我国人文与经济地理学发展高层论坛”在北京召开,与会的30余位专家就近年来我国人文与经济地理学发展的主要进展、学科发展存在的问题和制约因素、面临的发展机遇、学科发展的国际化道路、发展的主要重点方向与前景等议题开展了深入交流和研讨。近年来人文与经济地理学蓬勃发展,当前面临着一系列发展的重要机遇,未来发展有着广阔空间。建立学术共同体,针对重大问题开展联合攻关和协同创新;兼容本土化特色与国际化道路,促进中国人文与经济地理学走向世界;推动各系列人才梯队建设和中青年人才成长。     

中国高速公路网的可达性格局及演化

在全国尺度上评价1988~2030年中国高速公路可达性的空间格局及演化。基于交通旅行时间和最短时间路径的可达性模型设计,刻画了中国高速公路网的扩张过程,评价各时段中国高速公路网的通达性及演变,包括连通城镇、交通时间和时间区位系数等,分析各地区可达性的空间差异及变化特征,以及各时段内可达性的变化差异,重点识别可达性与区位受损和收益的突出区域;结合人口和经济等属性指标,评价各城市的综合发展潜能及变化。研究发现,高速公路建设拉近了边缘地区与核心地区的时间距离,西部地区的交通条件得到了很大改善,但并没有改变各城市的区位优劣水平,而且导致城市间发展潜力的差距更加不平衡。     

中国道路网络的演化、通达性评价与发展机理(英文)

Before the emergence of modern modes of transport, the traditional road infrastructure was the major historical means of carrying out nationwide socio-economic exchange. However, the history of transport infrastructure has received little attention from researchers. Given this background, the work reported here examined the long-term development of transport networks in China. The national road network was selected for study and the 3500 years from 1600 BC to 1900 AD was chosen as the study period. Indicators were designed for the maturity level of road networks and an accessibility model was developed for the paths of the shortest distance. The evolution of the road network in China since the Shang Dynasty(1600 BC) was described and its major features were summarized to reveal long-term regularities. The maturity level of the road network and its accessibility was assessed and regions with good and poor networks were identified. The relationship between China’s natural, social, and economic systems and the road network were discussed. Our analysis shows that the road network in China has a number of long-term regularities. The continuously expanding road network follows a path of inland expansion especially towards the border areas. However, its coverage and accessibility are characterized by a core–peripheral configuration, which has close relationships with, not only the natural conditions, but also national defense and warfare. The centralization of national power, national land governance, postal transport, the transport of specialized cargos, and international trade are also related to the development of the road network. This research draws attention to the evolving regularities of transport networks.     

Changes in the angular separation of the lensed images PKS 1830-211 NE & SW

We present 8 epochs of 7 mm dual-polarization VLBA observations of the gravitational lens system PKS 1830-211 made over the course of 14 weeks. Clear changes in the relative positions of the cores of up to 80 μarcseconds (μas) were observed between epochs (each separated by ≈2 weeks). A comparison with previous 7 mm VLBA maps shows that the separation of the cores has changed by almost 280 μas over 12 months. This leads us to conclude that changes in the brightness distribution of the mm-VLBI core of the background source must be occurring rapidly. This is the first clear observation of significant radio source evolution in a gravitational lens system. It is also the first time that changes in source structure have been detected in a distant extra-galactic source on such short time-scales. This is partly accounted for by the magnification provided by the lens system.