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随着我国居民生活水平的日益提高,人们对城市居住区的选取提出了更高的要求。本文基于ArcGIS的空间分析功能,对不同的居住区进行分析和比较,在分析过程中分别选择一些具有代表性的影响因素,通过这些影响因素对城市居住区宜居性进行空间评价。 相似文献
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FACTORS AFFECTING FORMATION AND DEVELOPMENT OF THE URBAN INDUSTRIAL DISTRICT IN CHINA──A Case StudyonCaohejingHi-TechParkinSh... 相似文献
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天宫一号数据地表温度反演及其在城市热岛效应中的应用 总被引:2,自引:1,他引:1
针对天宫一号高光谱成像仪红外波段数据提出了一个单通道地表温度反演算法,算法的输入参数为大气水汽含量和地表发射率.利用模拟数据和黑河流域生态—水文过程综合遥感观测联合试验的地面实测数据对算法进行了精度评价,结果表明算法的均方根误差为2.72 K,能够满足大多数应用研究的需求.以北京市二环以内为研究区域,采用4个时相的天宫一号高光谱红外波段数据进行了城市热岛效应研究,结果表明天宫一号高光谱红外波段数据适合用来进行街区尺度的城市热岛效应研究,具有很大的应用潜力. 相似文献
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Storm extreme levels and coastal flood hazards: A parametric approach on the French coast of Languedoc (district of Leucate) 总被引:1,自引:0,他引:1
Brice Anselme Paul Durand Yves-François Thomas Alexandre Nicolae-Lerma 《Comptes Rendus Geoscience》2011,343(10):677-690
Coastal flooding is a significant risk on the shores of Languedoc-Roussillon. The storms that periodically hit the coast can generate strong swells and storm surges. Most beach resorts, built on a low elevation dune ridge, are periodically flooded during major storms. Although risks zoning regulations take into consideration coastal flood hazards, the delineation of vulnerable areas is still insufficient and the commonly accepted threshold is regularly exceeded during most severe storms. This paper presents a method to improve the assessment of extreme storm-related water levels. It relies on fieldwork carried out in the Leucate commune (Aude), which is particularly exposed to the risk of sea level rise. It considers both storm surges and wave phenomena that occur within the surf zone (set-up and swash), calculated from the Simulating WAves Nearshore (SWAN®) numerical wave model and the Stockdon formula. Water levels reached during several recent storm events have been reconstructed and simulations of submerged areas were carried out by numerical modelling. 相似文献
788.
Shui-Yuan Yang Shao-Yong Jiang Liang Li Yan Sun Ming-Zhi Sun Li-Zeng Bian Yong-Gen Xiong Zhong-Qing Cao 《Gondwana Research》2011,20(4):831-843
The Middle–Lower Yangtze River metallogenic belt (MLYRMB), extending from Daye in Hubei Province in the west to Zhenjiang in Jiangsu Province in the east, hosts a number of large polymetallic (Cu–Au–Mo, Fe, Zn, Pb, and Ag) deposits and constitutes one of the most important metallogenic belts in China. The Cu–Au–Mo deposits in the Jiurui district are an important component of the MLYRMB. In this study we carried out precise and detailed zircon U–Pb dating for all types of magmatic rocks from the Wushan ore deposit in the Jiurui district. Three samples of Cu–Au–Mo-related porphyries from different ore belts at Wushan were analyzed and yielded zircon U–Pb ages of 148.0 ± 1.0 Ma, 145.4 ± 0.9 Ma and 147.3 ± 0.9 Ma, respectively. A series of dykes were emplaced immediately following the Cu–Au–Mo-related porphyries at Wushan. A dark-colored basic dyke which intruded into the granodiorite porphyry at Wujia gold deposit near Wushan was dated at 144.5 ± 1.2 Ma. Two lamprophyre dykes taken from the north ore belt at Wushan underground mining stops were dated at 143.6 ± 0.9 Ma and 144.3 ± 0.9 Ma, respectively. A late-stage dyke which was also taken from the Wushan north ore belt yielded an age of 142.6 ± 1.0 Ma and might represent the end of magmatism in the Wushan ore deposit. These new geochronological data demonstrate that the time range of magmatism in the Wushan ore deposit is approximately between 148 Ma and 143 Ma, showing that the magmatic activity at Wushan was rapid and intensive. The ages of Cu–Au–Mo-related porphyries from other areas in the Jiurui district, such as the Dongleiwan, Yangjishan and Chengmenba ore deposits, were also measured and yielded zircon U–Pb ages of 141.5 ± 1.7 Ma, 143.4 ± 1.4 Ma and 146.6 ± 1.0 Ma, respectively. Combined with those previously reported zircon U–Pb age results from the Jiurui district, the present age data set demonstrates that extensive magmatism in the Jiurui district was coeval and intensive, marked by a magmatic activity in the age range of 148 to 138 Ma and peaked between 148 Ma and 142 Ma. According to the statistics of all those precise zircon U–Pb ages, the Cu–Au–Mo-related porphyries in the Edong and Tongling districts in the MLYRMB show similar ages, and they have a slightly younger peak age and a longer duration than that of the Jiurui district. The geographic shape of the MLYRMB in the Cretaceous shows an arcuate structure, the Jiurui district is located at the transitional point of the arcuate structure and the Edong and Tongling districts are situated on both sides of the arcuate structure. Considering that the Jiurui district has a slightly older peak age and a shorter duration of magmatic activity than that in the Edong and Tongling districts, it seems that the arcuate structure of the MLYRMB played an important role in the formation of these Cu–Au–Mo-related porphyries. Consequently, we suggest that the genesis of the Late Mesozoic magmatic rocks along the MLYRMB may have been due to a tectonic activity developed from southeast to northwest, which probably has a close relationship with the subduction of the paleo-Pacific plate beneath the Eurasian plate in Mesozoic times. 相似文献
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产业区演化研究的主要领域与进展——兼论对创意产业区演化研究的启示 总被引:1,自引:1,他引:0
产业区是20世纪80年代以来经济地理学研究的核心领域之一,作为城市经济发展的重要场所及产物和城市空间类型之一,其形成与发展引起了国内外学界高度关注。梳理文献发现产业区研究主要集中在:本质探究、形成机理、演化时间过程及未来趋向等方面,然现有研究存在如下问题:①未能形成产业区演化研究的理论框架;②研究视角虽较为多元,但大都孤立地讨论产业区演化,研究思路过于追求学科特色而缺乏综合性研究逻辑,无法将其嵌入城市与区域发展之中;③鲜有关注以生产性服务业、创意产业为主导的产业区演化。针对现有问题,借鉴演化经济地理学从产业区演化的动力来源、时一空过程、景观表征入手,界定了产业区演化的概念和内涵,构建了产业区演化研究范式,并针对后工业社会创意产业区或创意集群的演化现象,提出了研究建议。 相似文献