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111.
This paper puts forward the concept of land use structure optimization under space-time coupling through analyzing the systematic characteristic of land use structure optimization. It mainly expounds the construction of land use structure optimization model at different levels. Lastly, this paper explains the practicableness of land use structure optimization under systematic framework through the example of Qionghai city. 相似文献
112.
Xiang Chen Mei-Po Kwan 《International journal of geographical information science》2013,27(5):941-961
In classical time geography, an individual travel path is composed of a chain of visits, with each visit being a flexible activity between two fixed activities at two known stations. In reality, individuals tend to carry out trips with much variation and complexity, with multipurpose trips being a prominent and pervasive phenomenon. There is limited research to date on multipurpose trips in time-geographic analysis by geographic information system (GIS) scientists, or more specifically, multiple flexible activities between two fixed stations. To fill this gap, this article proposes four models for identifying the choice set with multiple flexible activities under space–time constraints. The models are derived through set-theoretic formalism based on the concept of trip chaining. The structure of the four models establishes a theoretical framework for conceptualizing trip-chaining behaviour with respect to the fixity of activities and the number of fixed stations as destinations or origins. They provide fundamental and rigorous apparatus for studying complex individual activity–travel patterns in many applied contexts when multipurpose trips are involved. This article also describes implementation of the models with a real transportation network as a way of validation. 相似文献
113.
滇西崇山剪切带南段左行走滑作用的构造特征及时代约束 总被引:7,自引:4,他引:3
作为保山地块与兰坪-思茅盆地的重要边界,崇山剪切带新生代以来经历了多阶段的构造变形;其中以大规模走滑韧性剪切作用最为明显,表现为北段以右行走滑剪切为主、南段以左行走滑剪切为主.本文通过对崇山剪切带南段永保桥-瓦窑桥剖面出露的崇山群石英片岩、片麻岩及糜棱岩等进行详细露头解析、室内显微构造观察以及变形石英的EBSD组构分析,认为崇山剪切带南段的岩石新生代以来至少经历了两期不同环境下的韧性变形:第一期(D1)为纯剪条件下的收缩变形,发生的温度条件大约在550 ~ 650℃(角闪岩相),表现为一些褶皱构造、石香肠或透镜体构造的发育及石英的C轴组构图呈斜方对称式;第二期(D2)为单剪递进条件下的左行走滑剪切变形,表现形式为走滑剪切面理的发育及各类岩石遭受韧性剪切变形从而改造成糜棱岩.此外,在崇山剪切带内发育一套含电气石花岗质脉体,根据详细的露头解析及显微构造分析,本文认为该套含电气石花岗质脉体是左行剪切作用初期阶段伴随的深熔作用的产物,为同剪切花岗岩脉.本文选取了两个含电气石花岗质脉体的样品进行了LA-ICP-MS锆石U-Pb测年,分别得到21.7±0.3Ma和22.7±0.3Ma的锆石U-Pb年龄,进一步表明了崇山剪切带南段的左行剪切作用起始时代在22Ma左右或略早于22Ma. 相似文献
114.
研究一种基于路网约束空间格局方法在交通事故分析中的应用,以武汉市13个区交通事故为研究对象,将交通事故抽象成道路网上的点要素,采用路网约束下的核密度估计方法,讨论其空间分布格局并与平面空间点聚类分析的结果进行对比分析,最后采用局部Moran's Ⅰ方法对道路基本单元网络核密度估计结果值进行判别,揭示0.01显著性水平下的武汉交通事故易发路段。实验结果表明,网络核密度估计算法可直观体现事故沿城市道路网的聚类模式,对核密度结果进行的局部Moran's Ⅰ统计方法能够有效地应用于易发路段的鉴别。 相似文献
115.
Lateral heterogeneities in the mantle can be caused by thermal, chemical and non-isotropic pre-stress effects. Here, we investigate the possibility of using observations of the glacial isostatic adjustment (GIA) process to constrain the thermal contribution to lateral variations in mantle viscosity. In particular, global historic relative sea level, GPS in Laurentide and Fennoscandia, altimetry together with tide-gauge data in the Great Lakes area, and GRACE data in Laurentide are used. The lateral viscosity perturbations are inferred from the seismic tomography model S20A by inserting the scaling factor β to determine the contribution of thermal effects versus compositional heterogeneity and non-isotropic pre-stress effects on lateral heterogeneity in mantle viscosity. When β = 1, lateral velocity variations are caused by thermal effects alone. With β < 1, the contribution of thermal effect decreases, so that for β = 0, there is no lateral viscosity variation and the Earth is laterally homogeneous. These lateral viscosity variations are superposed on four different reference models which differ significantly in the lower mantle viscosity. The Coupled Laplace Finite Element method is used to predict the GIA response on a spherical, self-gravitating, compressible, viscoelastic Earth with self-gravitating oceans, induced by the ICE-4G deglaciation model.Results show that the effect of β on uplift rates and gravity rate-of-change is not simple and involves the trade-off between the contribution of lateral viscosity variations in the transition zone and in the lower mantle. Models with small viscosity contrast in the lower mantle cannot explain the observed uplift rates in Laurentide and Fennoscandia. However, the RF3S20 model with a reference viscosity profile simplified from Peltier's VM2 with the value of β around 0.2–0.4 is found to explain most of the global RSL data, the uplift rates in Laurentide and Fennoscandia and the BIFROST horizontal velocity data. In addition, the changes in GIA signals caused by changes in the value of β are large enough to be detected by the data, although uncertainty in other parameters in the GIA models still exists. This may encourage us to further utilize GIA observations to constrain the thermal effect on mantle lateral heterogeneity as geodetic and satellite gravity measurements are improved. 相似文献
116.
矽卡岩型矿床是云南北衙金多金属矿区的一种主要矿床类型,受岩体、构造及层位等控制,其有利找矿空间为中酸性岩体与碳酸盐岩的接触带.以岩石物性为纽带,实现目标地质体与地球物理场的转换,提取有效信息.接触带中低电阻率、岩体的低密度性、铁矿的高磁性和高极化率等都是矽卡型铁矿床的特有地球物理属性.通过地质地球物理等多元信息的层层约束,解析不同级次的成矿要素问题,实现对隐伏矽卡岩型铁矿床的定位,建立地球物理勘探模式,并在矿区外围开展方法有效性的验证,取得了良好的勘探效果,提出一套适应于北衙地区及类似成矿地质背景下的隐伏矽卡岩型铁矿床定位预测方法. 相似文献
117.
LIU Yanfang HUANG Liangprofessor School of Resource Environment Science Wuhan University Luoyu Road Wuhan China. 《地球空间信息科学学报》2002,5(3):46-52
1 IntroductionThesystemoflanduseisaverycomplexsystem .Wedrawuptheprojectoflanduseplanningstructuretoimplementtheopti mizationoflandresources .Theoptimizationoflandusestruc tureisthekerneloflanduseplanning .Today,mostoftheurbanlanduseplansonlyconsidertheop… 相似文献
118.
塔里木盆地、四川盆地以及鄂尔多斯盆地深层-超深层碳酸盐岩油气藏是中国油气勘探的重要领域.由于中国海相深层碳酸盐岩储层发育的主控因素差异很大, 碳酸盐岩储集体类型多, 非均质性极强.随着深度增加, 海相地层地震资料信噪比低、分辨率变差, 增加了碳酸盐岩储层地震预测的难度.本文提出了以“相、面、断”三种端元为基础的深层碳酸盐岩储集体分类的新方法, 针对相控型、面控型和断控型三种类型储集体, 形成了相应的储集体预测方法、流程, 包括: (1)川西雷口坡组气田潮坪相白云岩薄储层“三型两构”组合预测技术; (2)川北茅口组气藏礁滩相白云岩薄储层地震沉积学分析约束的高分辨率反演技术; (3)顺北油气田奥陶系断控储集体基于振幅响应正演模拟的定性-定量描述; (4)大牛地奥陶系不整合面岩溶储集体地质规律指导下的波形分类与古地貌刻画技术.这些方法围绕特定类型储集体的特征, 充分运用地质分析所建立的储集体模式, 较好地预测了储集体的厚度、物性、含油气性及分布范围, 实现了单纯依据地震数据无法达到的预测目标, 取得了良好的应用效果, 有力支撑了深层-超深层油气勘探突破与高效开发.
相似文献119.
120.