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201.
Najat Qader Omar Mohd Sanusi S. Ahamad Wan Muhd Aminuddin Wan Hussin Narimah Samat Siti Zubaidah Binti Ahmad 《Journal of the Indian Society of Remote Sensing》2014,42(1):165-178
The cellular automata (CA) model is an important tool in land use change studies. Swift increases in population and long-term expectations of rapid urbanization have led to extensive land use change, and normal living conditions have affected the natural resources of the land. This paper highlights and analyzes the historical urban changes in Kirkuk City, Iraq, considering repeated changes undergone by the state such change as government infrastructures, wars, and economic blockade. In this paper, an integrated model, built-in multi regression model, and multi-criteria evaluation were considered to improve the representation of CA transition rules. Environmental and socioeconomic factors were used to produce Suitable Maps (SMs). These SMs were practicalities to create factor layers and weight usage, rating method process for variance expert decision-making groups, and geographic information systems for the periods 1984, 1990, 2000, and 2010. The roots of the equation (R2) values are compared and these values are chosen to produce a good model of suitable maps. The approach used in this study provides a mechanism for monitoring suitability maps in Kirkuk. Furthermore, the model Markov CA is implemented and evaluated. The results indicate that the model, its related concepts performs sufficiency 相似文献
202.
In this study, on the basis of the Floquet transform method, a numerical model for the simulation of the vibration isolation via multiple periodic pile rows with infinite number of piles is established. By means of the fictitious pile method due to Muki and Sternberg, the second kind of Fredholm integral equations for the pile rows are developed by using the fundamental solutions for the half‐space and the compatibility conditions between the piles and half‐space. Employing the Floquet transform method, integral equations for the pile rows in the wavenumber domain are then derived. Solution of the integral equations yields the wavenumber domain solution for the pile rows. The space domain solution can then be retrieved by inversion of the Floquet transform. Numerical results show that the proposed model with the Floquet transform method is in a good agreement with those of the conventional direct superposition method. On the basis of the new model, influences of the spacing between neighboring piles, the Young's modulus of the piles, and the pile length on the vibration isolation effect of the pile rows are investigated. Numerical simulations conducted in this study show that compared with the direct superposition method, the efficiency of the proposed model for simulation of the vibration isolation via pile rows is very high. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
203.
回顾了体系地震动力分析的历史过程,并对地震动力分析的传统理论方法、近似方法和现代计算技术从新的角度加以阐述,同时给出体系地震动力分析的应用前景,以促进经典的传统理论方法、近似方法和现代计算技术的综合和在实际工程中的应用,形成系统而完整的地震动力分析体系。 相似文献
204.
本文利用热成风适应原理,采取分解分析法对青藏高原500hpa暖性高压的生成机制作了一些定性和定量的讨论。结果表明:在扰动的水平尺度大于热成风适应的特征尺度的条件下,当源地有明显的负值非热成风涡度出现时,流场将向温度场适应,而温度场由于高原的加热作用存在暖中心或暖脊,则适应的结果在高原大气500hpa形成暖性高压,并伴随高层辐合,低层辐散及下沉运动。 相似文献
205.
用地基GPS资料分析大气可降水汽总量 总被引:16,自引:5,他引:11
利用“中国地壳运动监测网络”和三峡监测网的地基GPS资料,通过Bernese软件以及根据Bevis等和Rocken等水汽解算原理编制的水汽解算软件。获得了武汉、巴东、兴山、泸州等长江流域测站大气可降水汽总量分布和时间间隔为2小时的GPS遥感大气可降水汽序列,并与站点雨量及区域面雨量进行对比分析,结果表明:地基GPS遥感水汽量变化与地面降水有很好的相关性。而且GPS遥感水汽变化序列峰值对应于强降水提前了8~22小时。有助于强降水特别是突发性强降水的预测;多个站点的GPS遥感水汽总量联合分析,对于区域水汽总量变化研究有一定意义。 相似文献
206.
Remote sensing technique has played an important role in land use dynamic monitoring, but as for the land use dynamic monitoring
at county level, traditional remote sensing methods such as satellite imagery visual interpretation and computer classification
can not meet its demand for accuracy. The result of 1: 10 000 land use investigation map has high accuracy, but this method
can not be used to dynamically monitor the land use because of its big expenses, long period and difficulty in updating data.
In this paper, the characteristics of physiognomy, climate and the status of land use in Dehui County are taken into consideration
and a set of method, which takes use of 3S techniques and applies to Northeast China Plain, is come up with. When the land
use type of a land parcel changed as a whole, the date updating can be make by changing its land type ID in the attribute
table in a GIS. When the land use type of an irregular area changed, GPS receivers are used to position its border. This set
of method is characteristic of high accuracy and low expenses. It gets the information of land use change timely and can be
used to dynamically monitor the land use.
Foundation item: Under the auspices of the key project of the National Ninth Five-year Plan (96-B02-01-07).
Biography: LI Lin-yi (1968 —), female, a native of Jilin, Ph. D. candidate of Changchun Institute of Geography, the Chinese
Academy of Sciences. Her research interest includes land use change monitoring and crop yield estimation using “3S” techniques. 相似文献
207.
Jianhua Wan Qinting Sun Shanwei Liu Yinlong Li 《Journal of the Indian Society of Remote Sensing》2018,46(12):1939-1947
The characteristics of sea-level change in the China Sea and its vicinity are studied by combining TOPEX/Poseidon (T/P), Jason-1, Jason-2, and Jason-3 altimeter data. First, the sea-surface height is computed by using monthly data via collinear adjustment, regional selection, and crossover adjustment. The sea-level anomaly (SLA) from October 1992 to July 2017 is calculated based on the difference that is obtained by the value derived from the inverse distance weighting method to interpolate the CNES_CLS15 model value at a normal point. By analyzing the satellite data at the same time in orbit, three mean bias groups over the China Sea and its vicinity are obtained: the difference between T/P and Jason-1 is ??11.76 cm, the difference between Jason-1 and Jason-2 is 9.6 cm, and the difference between Jason-2 and Jason-3 is 2.42 cm. To establish an SLA series for 25 years in the study area, the SLAs are corrected. Mean rate of sea-level rise of the Bohai Sea, Yellow Sea, East China Sea, and South China Sea of 4.87 mm/a, 2.68 mm/a, 2.88 mm/a, and 4.67 mm/a, respectively, is found by analyzing the series of SLAs. 相似文献
208.
浑河断裂带是辽宁抚顺地区最为重要的一条活动断裂。为了深入调查沿浑河断裂带地质灾害发育情况,了解灾害形成与先存断裂之间的关系,为同类型灾害的防治和预警提供科学依据。本文采用现场调查方法,结合地面变形监测资料,厘清了浑河断裂带灾害类型和发育规律,剖析了断裂带灾害的形成机理。研究结果表明:断裂隐伏区地裂缝发育,主要沿浑河断裂带分支断裂展布,裂缝延伸长度300~2 400 m;其成因是抚顺城区南部采矿活动诱发了先存软弱断裂面局部拉裂、张开,进而向地表扩展、贯通,形成地裂缝。在断裂延伸的基岩地区沿断裂破碎带及影响带发育小型滑坡,主滑方向与断裂走向垂直或大角度斜交;其形成机制与岩体内部发育的结构面有关,尤其是顺坡向优势结构面的发育,其与坡体耦合形成易滑结构体,在长期降雨作用下,结构面软化、贯通及岩土体加速蠕滑,最终形成滑坡。 相似文献
209.
二十多年来,南海天然气水合物勘查评价均主要集中在南海北部大陆边缘陆坡深水区,且先后在珠江口盆地神狐、珠江口盆地东部海域调查区和琼东南盆地陵水-松南调查区取得了天然气水合物勘查试采的重大突破及进展,陆续发现了两个大规模的天然气水合物藏,初步评价预测南海天然气水合物资源规模达800亿吨油当量左右,取得了南海天然气水合物勘探的阶段性重大成果.然而,南海天然气水合物资源进一步深化和拓展勘探的有利领域在哪里?尤其是可持续滚动勘探的战略接替区及选区在何处?其与目前陆坡深水油气及水合物勘探紧密相邻的外陆坡-洋陆过渡带(OCT)乃至洋盆区是否具有天然气水合物形成的地质条件?根据海洋地质调查及初步的地质综合分析研究,认为外陆坡-洋陆过渡带乃至洋盆区具备天然气水合物成藏的基本地质条件,可作为南海未来天然气水合物勘查的战略接替区和可持续滚动勘探的战略选区及资源远景区.针对这些影响和决定将来天然气水合物勘探决策部署及走向等关键问题进行初步分析与探讨,抛砖引玉希望能够对未来南海天然气水合物资源勘查评价及战略接替区之选择有所裨益! 相似文献
210.