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1.
一、解译方法、原则与分类系统 (一) 解译依据 根据实测地物光谱特性,水的反射率低变化平缓。故卫星影象对水系、水体解译的主要标志是色调和图型。阴影是水系解译的参考标志。 采用MSS4、5、7图象,陆地卫星——4号的TM1、2图象,以及RBV黑白片。利用了7波段对水与周围岩性及其它地物反射率反差大的特点,对MSS多波段图象进行了单波段(MSS7/5)的图象处理方法。为分辨出时令河与常流河,以枯水期(十一月至次年四月)的影象为主,而对水体的处理则采用汛期(七、八月份)的图象。  相似文献   

2.
在陆地卫星资料的应用研究中,先对少量样本进行分析,然后上计算机处理,可以减少研究工作中的浪费与盲目性。本文以黄河下游大汶河为例,利用陆地卫星多谱段数据,对流域的稠密森林山地、稀疏林山地、草被灌丛山地、丘陵农田、平原农田、水体、城市等地物进行数值分析识别,并与常规目视解释作了比较。通过分析比较认为:陆地卫星单波段识别地物的功能,若以优劣评阶,影象的次序为:MSS5、MSS6、MSS7、MSS4,数值分析的次序为:MSS5、MSS7、MSS6、MSS4,但任一单波段都不能识别所选择的全部地物;由MSS5与MSS7构成的二维空间是识别流域地物的最佳判别空间;四个波段合成的彩色片可识别8类地物中的5种,具有良好的识别功能;利用MSS7~MSS5灰阶值点聚图及判别分析方法,可对流域地物进行识别分析,这种非计算机识别地物的数值法,适合于研究指定范围内样本的地物类型。  相似文献   

3.
许殿元 《地理研究》1986,5(3):63-68
本文介绍黄河口幅卫星遥感图象二次增强处理试验的技术和经验。本试验的目的是探寻卫星遥感图象地学应用的潜力,最终做出1:20万的黄河口三角洲地区彩色数字图象和黄河口局部子区1:10万彩色数字增强图象获得令人满意的地学应用效益。  相似文献   

4.
1.引言城市化的影响对发达和不发达国家都存在。现势性而又详细的信息对于城市规划十分重要。遥感方法可以提供这方面的某些信息。世界各地对用陆地卫星 MSS 数据进行城市区域分类作过很多研究。其成果之一就是建立了适用于遥感的城市区域分类系统。第一级是城市(建成区),第二级进一步细分成居住区、商业区、工业区和空地等,用陆地卫星 MSS 资料进行第二级或更低一级的划分成效不大。  相似文献   

5.
通过陆地卫星MSS4、5、7波段假彩色合成卫片的解泽(比例尺为1/50万),参考地质图、地貌图和全国第二次土壤普查分类系统。该图划分出十六个土类,四十四个亚类,现将各类土壤主要特征特性概述如下: A 黄棕壤:黄棕壤是我国北亚热带地区的地带性土壤。在我省主要分布在伏牛山主脉与沙河一线以南。该土硅铝率较低,明显的特征是心土层红棕至棕色,棱块或棱柱状结构,结构面有大量棕色或  相似文献   

6.
遥感数字图象处理用于山地研究中、对提高山地开发效益具有重要的意义。 一、山地遥感图象的特征 这主要表现为:1.由于地形起伏、太阳高度角和传感器扫描角度的不同,山地遥感图象就有阴影,处于阴影区和非阴影区的同类地物呈现不同的光谱特性,2.山区(特别是南方山区)雨水多,云量大,日照少,大气中的水汽对地物的光谱特性产生干扰,  相似文献   

7.
利用计算机进行图象处理和彩色制印,编制了京津及邻区1:25万影象图。采用经数字处理的图象和制图分析等编改工艺,取得了高质量低成本的效果。  相似文献   

8.
为提高土地覆盖分类精度,本文应用SPOT.HRV卫星图象,将其空间信息(增强处理图象)叠加到光谱信息(原图象)上的方法编制土地覆盖类型图,并设立9个探讨项目,通过分类精度检验表明:用增强处理图象进行分类时PCC从88.1%提高到92.2%,区分精度从91.0%提高到96.5%,误分率从19.0%减少到7.5%。作业效率也明显提高。  相似文献   

9.
基于MSS、TM、ETM+以及HJ-1等遥感影像,构建内蒙古锡林郭勒盟1975~2009年长时间序列生态系统宏观结数据库,分析区域生态系统空间分布格局、动态变化及驱动机制。研究表明:①草地生态系统是锡林郭勒盟主体生态系统,草地占全区总面积比例始终在86%以上。②锡林郭勒盟生态系统演变过程明显以2000年为界:2000年前草地生态系统持续、加速萎缩,荒漠、农田等生态系统不断扩张;2000年后草地生态系统萎缩迅速得到遏制和逆转,农田和荒漠等生态系统扩张趋势也得到遏制。③区域气候变化及人类土地利用活动对生态系统演变有显著加速和减速作用。  相似文献   

10.
用遥感技术来研究地下水,实质上是在各类遥感图象上寻找各种间接标志,以解译控制水文地质规律的众多因素,进而分析水文地质条件。遥感图象的种类很多,目前常用于水文地质研究的主要有航空象片、卫星图象和热红外扫描图象。  相似文献   

11.
毛赞猷 《地理学报》1989,44(4):459-468
对资源环境影象信息进行解译,最终要转换为不同类型的线划界线或图纹符号。计算机兼容磁带的图象处理,现在还难以对任何专题类型都能分类和转换成界线。因此,广泛应用的粗制卫星象片作信息解释后,还必须解决类型界线向地理底图正确转绘。本文着重分析按不同精度的影象图上类型界线转换问题。并提出,由于地理底图是经过制图综合的,它的点位精度比纠正后的景象图形精度低,转绘最后步骤应是手工的地理相关转绘。  相似文献   

12.
中国南极考察队第一次去东南极格罗夫山地进行考察之前 ,为了保证考察路线选择、导航和考察任务顺利进行 ,在无任何地面实地测量数据的情况下 ,采用星上参数处理并制成了1∶ 1 0万比例尺彩色卫星影像地图。通过对卫星影像的判读 ,对该地区的地形、地貌、蓝冰和陨石分布特点作了初步的分析和探讨 ,并勾画出可能有陨石分布的地区  相似文献   

13.
数字地形分析在滑坡研究中的应用综述   总被引:2,自引:0,他引:2  
高效的数字地形分析(Digital Terrain Analysis,DTA)是滑坡预测与评估研究的重要手段。文章综述了DTA在滑坡研究中的应用现状,基本内容包括地形因子分析、地形形态分析、地形单元划分以及DEM与滑坡模型的结合分析。地形因子分析的应用多而广,主要思路是在地形因子与滑坡发育的关系研究基础上分析其滑坡敏感性,进而构建滑坡预测和评估模型;地形形态分析是滑坡识别的重要手段,加强地貌形态和滑坡发育的关系研究有助于对潜在滑坡地形的识别;地形单元划分能为滑坡研究提供统计和分析单元;DEM与滑坡专业模型的结合方式多样,程度各异。同时,从尺度选择与转换的角度探讨了DTA滑坡研究的尺度问题,分析了DTA的局限性,指出DEM不能提供完备无误的地形信息,DTA不能完全取代常规的地形分析。最后,基于以上论述对未来的研究趋势提出了展望。  相似文献   

14.
Affine transformation that allows the axis-specific rotations and scalars to capture the more transformation details has been extensively applied in a variety of geospatial fields. In tradition, the computation of affine parameters and the transformation of non-common points are individually implemented, in which the coordinate errors only of the target system are taken into account although the coordinates in both target and source systems are inevitably contaminated by random errors. In this article, we propose the seamless affine error-in-variables (EIV) transformation model that computes the affine parameters and transforms the non-common points simultaneously, importantly taking into account the errors of all coordinates in both datum systems. Since the errors in coefficient matrix are involved, the seamless affine EIV model is nonlinear. We then derive its least squares iterative solution based on the Euler–Lagrange minimization method. As a case study, we apply the proposed seamless affine EIV model to the map rectification. The transformation accuracy is improved by up to 40%, compared with the traditional affine method. Naturally, the presented seamless affine EIV model can be applied to any application where the transformation estimation of points fields in the different systems is involved, for instance, the geodetic datum transformation, the remote sensing image matching, and the LiDAR point registration.  相似文献   

15.
基于匀光遥感的6000年来盐城海岸演变研究   总被引:2,自引:0,他引:2  
康彦彦  丁贤荣  程立刚  张晶 《地理学报》2010,65(9):1130-1136
本文研究盐城串场河一线至黄海60 km宽的海积平原海岸演变过程。对1975 年的MSS影像,进行遥感匀光处理、阈值分割等影像解译,获取了盐城海积平原古海岸演变解译图,即“斑马条纹”二值图;对19 个实测底质样品进行分析,发现海积平原呈现砂质(粗颗粒) 与淤泥质(细颗粒) 沉积相间平行的分布规律,而这一空间交替分布特征与解译图上“斑马条纹”的二值条带具有良好的对应关系;同时,搜集整理了近几十年来的盐城古海岸调查资料与研究成果,发现前人历史岸线的空间分布与“斑马条纹”整体趋势相同。综上所述,“斑马条纹”应为盐城海岸演变标志,解译出砂冈10 条,冈间低地10 条,形成了对盐城海积平原地貌沉积及海岸演变过程的新认识。  相似文献   

16.
基于GIS制作遥感影像地图的研究与实践   总被引:5,自引:0,他引:5  
遥感与地理信息系统一体化是科学技术发展的趋势,遥感影像地图是现代地图发展的新图型。本文介绍了基于CITYSTAR进行遥感影像地图编制的研究和实践,阐述了其工艺过程和关键技术,并以厦门和达竹两个例子说明具体的工作方法与步骤。  相似文献   

17.
The problem of incompatible projections and conversion between mapping systems is of general concern to those involved in the collection of natural resources data. The Ghana National Grid (GNG) is an example of a mapping system that is not defined in image processing and GIS software and for which the transformation parameters are not readily available in the literature. Consequently, integrating GNG topographic map data within a GIS with data derived from other sources can be problematic. In this paper a practical solution for deriving the required transformation parameters to convert from the World Geodetic System of 1984 (WGS84) to the GNG system is demonstrated. The method uses a single geodetic control point, available 1:50 000 topographic maps and a SPOT satellite panchromatic image geo-referenced to GNG. The resultant parameters are applied to road survey data in Universal Transverse Mercator (UTM) format for overlay with the SPOT image. Despite the approximations made in applying the method, when compared against official estimates of the datum transformation parameters, this relatively simple procedure resulted in estimates that appear acceptable in regard to combining data sets at a nominal scale of 1:50000.  相似文献   

18.
中国堵江滑坡发育分布特征   总被引:2,自引:0,他引:2  
在我国已经发现和识别出160余个堵江滑坡,根据这些实际资料,绘制了我国滑坡堵江事件分布图,研究表明,堵江滑坡的发育与我国的降雨分区、地形地貌、断裂分布、地震活动和地层岩性的分布密切相关,从而堵江滑坡灾害在时间上、空间上的发育分布具有一定的规律。  相似文献   

19.
With the rapid development of geospatial data capture technologies such as the Global Positioning System, more and higher accuracy data are now readily available to upgrade existing spatial datasets having lower accuracy using positional accuracy improvement (PAI) methods. Such methods may not achieve survey-accurate spatial datasets but can contribute to significant improvements in positional accuracy in a cost-effective manner. This article addresses a comparative study on PAI methods with applications to improve the spatial accuracy of the digital cadastral for Shanghai. Four critical issues are investigated: (1) the choice of improvement model in PAI adjustment; five PAI models are presented, namely the translation, scale and translation, similarity, affine, and second-order polynomial models; (2) the choice of estimation method in PAI adjustment; three estimation methods in PAI adjustment are proposed, namely the classical least squares (LS) adjustment, which assumes that only the observation vector contains error, the general least squares (GLS) adjustment, which regards both the ground and map coordinates of control points as observations with errors, and the total least squares (TLS) adjustment, which takes the errors in both the observation vector and the design matrix into account; (3) the impact of the configuration of ground control points (GCPs) on the result of PAI adjustment; 12 scenarios of GCP configurations are tested, including different numbers and distributions of GCPs; and (4) the deformation of geometric shape by the above-mentioned transformation models is presented in terms of area and perimeter.

The empirical experiment results for six test blocks in Shanghai demonstrated the following. (1) The translation model hardly improves the positional accuracy because it accounts only for the shift error within digital datasets. The other four models (i.e., the scale and translation, similarity, affine, and second-order polynomial models) significantly improve the positional accuracy, which is assessed at checkpoints (CKPs) by calculating the difference between the updated coordinates transformed from the map coordinates and the surveyed coordinates. On the basis of the refined Akaike information criterion, the two best optimal transformation models for PAI are determined as the scale and translation and affine transformation models. (2) The weighted sum of square errors obtained using the GLS and TLS methods are much less than those obtained using the classical least squares method. The result indicates that both the GLS and TLS estimation methods can achieve greater reliability and accuracy in PAI adjustment. (3) The configuration of GCPs has a considerable effect on the result of PAI adjustment. Thus, an optimal configuration scheme of GCPs is determined to obtain the highest positional accuracy in the study area. (4) Compared with the deformations of geometric shapes caused by the transformation models, the scale and translation model is found to be the best model for the study area.  相似文献   

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