地理国情普查试点成果综合分析     

张琴琴  杨柏林  李娜娜  张晓瑜 《测绘科学》2016,41(4):83-88

城镇服务设施布局的评价与分析是地理国情普查综合统计分析城镇化发展的重要内容。针对当前城镇化发展不平衡,生活服务设施空间布局不合理的情况,该文利用克拉玛依市独山子区地理国情普查试点成果,结合专题数据,采用GIS网络分析方法,在独山子区城镇综合设施之间配置最短最优路径。耦合结果表明:老城区卫生资源分布较合理,但是教育资源和整体服务设施分布却过于集中。这种方法还可以进一步用于优化城镇功能单元布局与服务保障设施点的建设,完善居民出行、教育、日常生活和文化服务等方面。  相似文献   

生态敏感性限制下的城市建设用地适宜性评价     

崔耀平  吕可文  何春玲  路婧琦  张帅帅  黄向球  冯永杰  麻永健 《测绘科学》2016,41(9):47-53,59

针对当前城市规划中对建设用地适宜性评价框架的不尽合理问题,以河南省西峡县为例构建了包含主导性和限制性逻辑的综合评价方案。利用遥感与地理信息系统相结合的方法,将生态敏感性作为限制性因素进行城市建设用地适宜性研究。研究区的分析结果显示:西峡县整体新增城镇建设区呈现南北区域不适宜而中间适宜的特征,而适宜和较适宜城市建设的用地主要分布在鹳河及其支流形成的河谷地带。但在中心城区外缘某些区域生态敏感性强,应禁止开发活动。研究结果有效体现出建设用地和生态用地的空间格局,对城市总体规划具有一定的参考价值。  相似文献   

改进支持向量机的高分遥感影像道路提取   总被引：2，自引：0，他引：2  

朱恩泽  宋伟东  戴激光 《测绘科学》2016,41(12):224-228

针对支持向量机受分类数的限制在高分辨率遥感影像中无法直接获取高精度道路网信息的问题,该文提出一种新的混合的基于支持向量机的方法:首先,利用模糊C均值聚类方法将输入的遥感影像分为3类,以减少支持向量机的错分现象;其次,运用支持向量机将不同类别的像素分为道路类和非道路类;最后,应用马尔科夫随机场对分类结果进行噪声去除,并采用形态学进行后处理,进而得到精确道路网信息。实验结果表明:该算法不仅能够从高分辨率遥感影像中提取出道路网,而且精度优于直接使用支持向量机算法以及对比算法。  相似文献   

顾及拓扑与尖角的分类矢量数据分组压缩算法   总被引：1，自引：1，他引：0  

宋正祥  周晓光  陈律余 《测绘科学》2016,41(11):98-103

针对现有拆分重组法对存在复杂内环以及复杂相交岛屿多边形的分类矢量数据的压缩结果中包含裂缝、重叠及大量尖锐夹角的问题,提出了一种顾及拓扑一致性与尖角的分组压缩方法。依据分类矢量数据中多边形与多边形及其内环的相交关系对矢量矢量数据分组,以修正后拆分重组法结合直接分割法和间接分割法对分类矢量数据分组压缩,压缩结果中不存在裂缝与重叠现象,维护了分类矢量数据的拓扑一致性;通过取回尖角点前后被删除的点,解决了压缩结果中尖角过多的问题。以Landsat8遥感影像分类矢量数据实验验证了文章算法,并与直接分割法、间接分割法、拆分重组法进行了对比分析,验证了本文方法的有效性。  相似文献   

An open source GIS‐based Planning Support System: Application to the land use plan of La Troncal,Ecuador          下载免费PDF全文

Inés Santé  Natalia Pacurucu  Marcos Boullón  Andrés Manuel García  David Miranda 《Transactions in GIS》2016,20(6):976-990

Planning Support Systems (PSS) comprise a wide variety of geo‐technological tools related to GIS and spatial modeling aimed at addressing land planning processes. This article describes the OpenRules system, a PSS based on a previous system called RULES. Among OpenRules new features are its architecture, based exclusively on free and open source software, and its applicability to all land use types, including rural and urban uses. In addition, OpenRules incorporates an unlimited number of land evaluation factors and a new objective in land use spatial allocation. OpenRules has been programmed in Java and implemented as a module of the free GIS software gvSIG, with full integration between the GIS and the decision support tools. Decision support tools include multicriteria evaluation, multiobjective linear programming and heuristic techniques, which support three basic stages of land use planning processes, namely land suitability evaluation, land use area optimization and land use spatial allocation. The application of OpenRules to the region of La Troncal, Ecuador, demonstrates its capability to generate alternative and coherent solutions through a scientific and justified procedure at low cost in terms of time and resources.  相似文献   

Integrating cellular automata,artificial neural network,and fuzzy set theory to simulate threatened orchards: application to Maragheh,Iran   总被引：1，自引：0，他引：1  

Mehdi Azari  Amin Tayyebi  Marco Helbich  Mohsen Ahadnejad Reveshty 《地理信息系统科学与遥感》2016,53(2):183-205

Urbanization processes challenge the growth of orchards in many cities in Iran. In Maragheh, orchards are crucial ecological, economical, and tourist sources. To explore orchards threatened by urban expansion, this study first aims to develop a new model by coupling cellular automata (CA) and artificial neural network with fuzzy set theory (CA–ANN–Fuzzy). While fuzzy set theory captures the uncertainty associated with transition rules, the ANN considers spatial and temporal nonlinearities of the driving forces underlying the urban growth processes. Second, the CA–ANN–Fuzzy model is compared with two existing approaches, namely a basic CA and a CA coupled with an ANN (CA–ANN). Third, we quantify the amount of orchard loss during the last three decades as well as for the upcoming years up to 2025. Results show that CA–ANN–Fuzzy with 83% kappa coefficient performs significantly better than conventional CA (with 51% kappa coefficient) and CA–ANN (with 79% kappa coefficient) models in simulating orchard loss. The historical data shows a considerable loss of 26% during the last three decades, while the CA–ANN–Fuzzy simulation reveals a considerable future loss of 7% of Maragheh’s orchards in 2025 due to urbanization. These areas require special attention and must be protected by the local government and decision-makers.  相似文献   

基于最优分割分级法的月球撞击坑分级及其演化分析     

姚美娟  陈建平  王翔  徐彬 《岩石学报》2016,32(1):119-126

撞击坑是月球表面广泛分布的重要构造形态,占据了月球表面的大部分面积。撞击坑的直径差别很大,从几微米到数百千米,其退化程度与形成年代具有密切关系。为了研究不同地质年代形成的撞击坑直径大小及其演化规律,需采用量化分级方法对大小不同的撞击坑进行定量分级和统计分析。本文在月表撞击坑数据库LU60645GT和Lunar_Impact_Crater_Database(2011)的基础上,结合数据库中撞击坑的直径、深度和年代信息,利用最优分割分级法对撞击坑直径进行定量化分级,并根据分级结果,综合分析撞击坑几何形态特征及其演化规律。研究结果表明,撞击坑形态特征的演化与年代有密切的关系。在相同级别、相同地体下,撞击坑形成的年代越早,其形态特征的精细结构退化程度越明显,只保留了大体的几何形状;而在不同级别、相同地体、相同年代下的撞击坑形态特征则由简单逐渐变为复杂,坑物质也逐渐变得复杂。  相似文献   

Modification of strain wedge method for lateral soil-pile interaction in sandEI北大核心CSCD     

Yang Xiao-feng  Zhang Chen-rong  Huang Mao-song  Yuan Ju-yun 《岩土力学》2016,(10):2877-2884

A modified strain wedge (SW) method for analyzing the behavior of laterally loaded single piles in sand is proposed. The modified model assumes that the lateral displacements of a pile behind the three-dimensional passive soil wedge are nonlinear, which makes the horizontal soil strain variable with depths instead of a constant value in the original strain wedge model, and also employs two different hyperbolic models, one for describing horizontal stress increment-strain behavior of soil in the wedge, and the other for describing the shear stress-displacement property at the interface between soil and pile shafts. An example is analyzed to demonstrate the effectiveness of the modified method, and a good agreement is obtained. Finally, the effects of modifications on the lateral bearing capacity of pile shafts are discussed. The results show that the problem of overestimating the lateral bearing capacity of piles with strain wedge method can be ameliorated by introducing the assumption of nonlinear lateral displacements of piles. It makes the SW method more convenient and effective in analyzing the behavior of laterally loaded piles by introducing the new relationships of horizontal stress increment-strain and shear stress-displacement.  相似文献   

Coupled Model of Two-phase Debris Flow, Sediment Transport and Morphological Evolution     

HE Siming  OUYANG Chaojun  LIU Wei  WANG Dongpo 《《地质学报》英文版》2016,90(6):2206-2215

The volume fraction of the solid and liquid phase of debris flows,which evolves simultaneously across terrains,largely determines the dynamic property of debris flows. The entrainment process significantly influences the amplitude of the volume fraction. In this paper,we present a depth-averaged two-phase debris-flow model describing the simultaneous evolution of the phase velocity and depth,the solid and fluid volume fractions and the bed morphological evolution. The model employs the Mohr–Coulomb plasticity for the solid stress,and the fluid stress is modeled as a Newtonian viscous stress. The interfacial momentum transfer includes viscous drag and buoyancy. A new extended entrainment rate formula that satisfies the boundary momentum jump condition(Iverson and Ouyang,2015) is presented. In this formula,the basal traction stress is a function of the solid volume fraction and can take advantage of both the Coulomb and velocity-dependent friction models. A finite volume method using Roe's Riemann approximation is suggested to solve the equations. Three computational cases are conducted and compared with experiments or previous results. The results show that the current computational model and framework are robust and suitable for capturing the characteristics of debris flows.  相似文献   

柴达木盆地南缘玛兴大湾地区典型岩浆岩岩性识别研究          下载免费PDF全文

魏本赞  汪冰  石海岗  付丽华  张策  揭文辉 《地质找矿论丛》2016,31(4):564-569

本文运用ASTER多光谱遥感数据识别柴达木南缘玛兴大湾地区典型岩浆岩的岩性信息,分别采用光谱分析法和最小噪声变换法进行试验,可有效地识别与提取出研究区内的典型岩浆岩岩性信息;经已知地质资料和野外查证资料分析证明,用上述方法提取岩性信息的结果可靠,能为岩性填图及矿床勘查工作提供参考。  相似文献