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191.
Urban Construction Land Suitability Evaluation Based on Improved Multi-criteria Evaluation Based on GIS (MCE-GIS): Case of New Hefei City,China 总被引:2,自引:0,他引:2
Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS (MCE-GIS), is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects: a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process (AHP) method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination (WLC) and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei. 相似文献
192.
Three-River Headwaters(TRH) region involved in this paper refers to the source region of the Changjiang(Yangtze) River,the Huanghe(Yellow) River and the Lancang River in China.Taking the TRH region of the Qinghai-Tibet Plateau as a case,the annual evapotranspiration(ET) model developed by Zhang et al.(2001) was applied to evaluate mean annual ET in the alpine area,and the response of annual ET to land use change was analyzed.The plant-available water coefficient(w) of Zhang’s model was revised by using vegetation-temperature condition index(VTCI) before annual ET was calculated in alpine area.The future land use scenario,an input of ET model,was spatially simulated by using the conversion of land use and its effects at small regional extent(CLUE-S) to study the response of ET to land use change.Results show that the relative errors between the simulated ET and that calculated by using water balance equation were 3.81% and the index of agreement was 0.69.This indicates that Zhang’s ET model based on revised plant-available water coefficient is a scientific and practical tool to estimate the annual ET in the alpine area.The annual ET in 2000 in the study area was 221.2 mm,11.6 mm more than that in 1980.Average annual ET decreased from southeast to northwest,but the change of annual ET between 1980 and 2000 increased from southeast to northwest.As a vast and sparsely populated area,the population in the TRH region was extremely unbalanced and land use change was concentrated in very small regions.Thus,land use change had little effect on total annual ET in the study area but a great impact on its spatial distribution,and the effect of land use change on ET decreased with increasing precipitation.ET was most sensitive to the interconversion between forest and unused land,and was least sensitive to the interconversion between cropland and low-covered grassland. 相似文献
193.
针对现有速度场模型采用数据少、现势性不强的问题,详细论述了速度场模型建立的数据获取与处理方法,利用中国大陆地壳运动监测网络中260个连续运行基准站2011~2015年的连续观测数据,采用GAMIT/GLOBK与GMT软件,获得高精度的定位及速度成果,并基于上述速度成果采用克里金插值法构建了中国大陆地壳运动速度场1°×1°格网模型。最后利用IERS公布的中国区域7个IGS站实测速度以及全国范围内均匀分布的陆态网络区域站实测速度,对模型内插结果进行检核,验证了模型的现势性、精确性和可靠性。 相似文献
194.
深基坑开挖与支护的有限元模拟 总被引:5,自引:0,他引:5
采用弹塑性有限单元法对超大基坑的开挖与支护进行数值模拟,据此分析土体的位移、主应力分布、施工过程中支护结构受力,并比较基坑顶部水平位移的计算值与实测值,两者非常接近,计算结果较为理想,可为工程设计和现场施工提供理论参考和指导. 相似文献
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197.
RFID(射频识别)中间件技术是RFID产业化的关键技术,分布式环境下的信息交换是这项技术的主要研究方向之一。随着企业对空间位置信息的关注需求日益增大,空间信息服务也成为RFID中间件中必不可少的组成部分。本文介绍了RFID中间件和空间信息服务的概念,通过一个RFID物流管理系统应用实例研究了空间信息服务在RFID中间件中提供空间信息操作,处理与交换的应用。 相似文献
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199.
分析了金属套管井中有限尺寸线圈的电磁响应特征,讨论了井眼泥浆参数、套管参数和不同线圈尺寸对电磁测井响应的影响,考察了金属套管中电磁测井对地层电阻率变化的灵敏度.径向非均匀介质的模拟计算表明,在套管井中井眼泥浆对电磁测井的影响较大,必须进行校正.在低频条件下,井间测量响应中金属套管与地层的电磁响应是非耦合的,两者可以分离.在套管参数一定时,套管响应与地层的响应的比值近似一个常数.电磁响应对地层电阻变化的灵敏度分析显示,井间电磁测量在储层研究尺度对地层电阻率变化响应灵敏,套管引起的衰减稳定.在其它参数相同的前提下,线圈直径的增大有助于有效电磁响应信号的增强,给大井间距测量提供了可能.不同磁导率金属套管的电磁响应分析表明,电磁测井中,采用非磁性或弱磁性套管要优于一般的铁磁性套管. 相似文献
200.
首先从麦克斯韦方程出发,用伽里金方法推导了三维三分量CSAMT法的有限元方程.在研究过程中,认识到加入散度条件的必要性,在公式中强加了散度条件,提高了解的完备性.其次将成功应用于二维线源频率域电磁法有限元模拟中的两种技术推广到三维中,一是边界条件统一采用一阶吸收边界,使线源产生的电磁波在边界上按波的传播规律被吸收,以降低平面波假设造成的影响;二是总体系数矩阵的存储,用两个二维数组分别记录总体系数矩阵的非零元素及其在总体结点编号中所处的位置,使总体系数矩阵的存储量达到最小的同时,物理意义明确,迭代求解时迅速简便.最后用均匀半空间模型进行了验证. 相似文献