Regional tectonics, small-scale structures and microstructures in the ductile shearing zone are proved to be similar to each other in geometry and kinematics by comparing their patterns, so the methods for studying microstructures were used to the strain analysis in a ductile shearing zone in East Tianshan region with the aid of remote sensing. According to the theory of fractal, the methods for studying microstructures are suitable for the study of regional tectonics, as evidenced by their comparison with existing achievements. The combination of fractal with remote sensing might be a new development direction in geological survey.
In classifying the high-resolution remotely sensed data,the method applying the object-oriented image analysis is better than that applying the traditional pixel-oriented analysis. The first key step is the image segmentation for applying the object-oriented analysis. The results of the segmentation are the acquisition of a series of objects related to the real objects. The veracity of the segmentation is related to the selected segmentation scale. This paper has studied the selection of the segmentation scale of the high-resolution remotely sensed data obtained in Chengdu plain, applied different scales for image segmentation and compared the results. It is found that the best scale is 30, the same as the scale with which the mean brightness of the image objects has the maximum standard deviation.
This paper presents a newly developed method for SAR image geometric correction which lies in the dual-aspect geometric correction based on DEM to overcome the inherent shortages of Synthetic Aperture Radar (SAR) image such as foreshortening, shadow and layover, and correct the distorted or lost backscatter coefficient values in mountain areas. The geometric distortion of SAR images strongly limits the application of such images, especially in forestry inventory. The Terra SAR-X SAR images were used in this study. The results show that this method can effectively eliminate the effect of geometric distortions and compensate the lost or distorted backscatter coefficients, and is especially useful in eliminating layover and shadow distortions in SAR images. This method thus solves the geometric correction problem that cannot be solved with single SAR image.
Owing to the effects of the bigger Field-of-View (FOV), atmospheric attenuation, non-Lambertian reflectance of ground objects and the sun-object-sensor geometry, the radiance of airborne hyperspectral imaging spectrometer image tends to be distorted along the scanning lines, and hence it is difficult to use these data directly for quantitative or semi-quantitative applications. This study tried to correct the radiometric distortion of hyperspectral images of OMIS-II (Operative Modular Imaging Spectrometer) by using histogram matching and moment matching algorithms. The results indicate that, for space dimension, the two methods are all capable of retrieving the information of the blurred image edge, with no difference between them, whereas for spectrum dimension, moment matching is more fit for edge radiation distortion correction of OMIS-II.
This paper examined the atmospheric correction of HJ-1 CCD data using an approach of look-up table created from 6S model to acquire land surface reflectance. The result shows that the image after the correction is much better than the original one, indicating that the attenuation of NDVI can be rectified to improve the application of HJ-1 CCD data for remote sensing of vegetation. Aerosol optical depth is required for the correction. In order to ensure the precision of the correction, the authors suggest that the required aerosol optical depth can be retrieved from the hyper-spectral data on the same platform as the HJ-1-A data. As for the HJ-1-B data, the aerosol optical depth can be estimated by using the contrast reduction method with consideration of the land surface BRDF.
Statistical matched filter detection algorithms can be applied to target detection in hyperspectral imagery. The calculation of the background covariance matrix is used in any statistical matched filters, including Adaptive Coherence Estimator (ACE) and Constrained Energy Minimization (CEM) presented in this paper. Experiments on the calculation of the background covariance matrix from different background regions and the utilization of ROC curve give a comparative analysis of the problem as to how different background regions affect the detection performance of ACE and CEM.
Spectral reconstruction is a prerequisite for quantitative analysis of hyperspectral data, and atmospheric correction is the key step to spectral reconstruction. The atmospheric radiative transfer model is the most feasible method for hyperspectral data without simultaneous measurement of the ground. In this paper, the prevalent atmospheric radiative transfer models MODTRAN4.0 and 6S were used respectively for atmospheric correction and spectral reconstruction of EO-1’s Hyperion hyperspectral data in the study areas. Then the results of the correction using the atmospheric radiative transfer model and the applicability of the model were evaluated by comparing three types of reconstructed spectra respectively from vegetation, clay mineral and water and by calculating accuracy of spectral reconstruction using the statistical method. The superiority of integrated processing is reflected in the end by the application of FLAASH model.
Atmospheric water vapor is one of the key factors affecting the retrieval of land surface temperature (LST) from the single-band infrared image. It is conductive to the rational usage of single-band infrared data to find out the influence of spatial heterogeneity of AWV on the retrieval of LST. With the MODIS MOD05_L2 products as data sources, this paper discussed the spatial heterogeneity of AWV at the regional scale and its impact on the retrieval of LST from Landsat image. Firstly, an error model was deduced with regard to the influence of AWV on the retrieval of LST from remote sensing data. Then, in order to explore the retrieval error of LST possibly caused by the spatial heterogeneity of AWV at the regional scale, the authors conducted simulation tests followed by comparative analyses under spatially different distribution conditions of AWV in several regions, particularly for the thermal infrared band of Landsat 5. Results obtained in this paper indicate that the retrieval error of LST caused by the spatial heterogeneity of AWV has to do with the value and the heterogeneity degree of AWV. For example, when AWV had relatively high heterogeneity, an error was relatively great, ranging from 0.5℃ to 2℃ with relative error from 2% to 20% accordingly; by contrast, when AWV was relatively uniform, error was comparatively insignificant and ranged from 0.1℃ to 0.2℃ with relative error from 0.5% to 2% accordingly. In conclusion, with regard to regions with a relatively high degree of atmospheric heterogeneity, it is vital to get atmospheric parameters properly at the regional scale so as to retrieve LST precisely from remote sensing data.
POS (Position and Orientation System) provides position and attitude information during aerial photography. There must be at least one reference GPS base station for traditional differential GPS (DGPS) positioning, and the establishment of a GPS station would be a very costly and difficult task in some areas. GPS Precise Point Positioning (PPP) has been advanced as a way to avoid the use of the GPS base station. This paper describes the approaches to the processing of an actual aerial photographic data by using both kinds of GPS positioning methods. The final results of the POS-supported aerial triangulation from PPP are compared with those from DGPS solution. The empirical results suggest that the accuracy of POS-supported aerial triangulation from PPP can satisfy the 1∶2 000 topographic map specifications for aerophotogrammetric office operation. It is feasible to process the POS data of ADS40 without a GPS Base Station by using Precise Point Positioning.
Gain and Bias are two basic parameters for the reflectance calculation of TM images. The deviations of the two parameters will lead to the erroneous results of radiometric calibration, radiometric correction and atmospheric correction. Because of the ageing of Landsat-5 TM and the decrease of the radiation accuracy to some extent, the USGS has published different parameters of radiation correction in the past few years. Based on the Gain and Bias values acquired from the USGS and the image head file, the authors calculated the surface reflectance of water and vegetation and compared the calculation result with the standard reflectance. The results show that the Gain and Bias acquired from the head file is the best way. If the image has no head file, the Gain and Bias offered by the USGS could be used.
In this paper, the enrichment factors and pollution indexes of heavy metals were used to evaluate the heavy metal pollution condition of the floodplain topsoil in Jishui River. Based on the pollution indicators, the authors have reached the conclusion that all the floodplain topsoil at the sampling points has been polluted in various degrees. An analysis of heavy metal accumulation rate of Miscanthus floridulus reveals that Miscanthus floridulus has relatively strong absorption capacity for Cu, Zn and Cr. An opposite tendency is shown between the heavy metal absorption capacity of Miscanthus floridulus leaves and the heavy metal pollution condition in floodplain topsoil of the Jishui River. Furthermore, correlation analysis was made between two spectral features parameters (A1 means the integral value of visible light and A2 the integral value of near-infrared) and content of three heavy metals (Cu, Zn, Cr) in the leaves of Miscanthus floridulus. As a result, two multiple regression equations between the spectral features and the content of three heavy metals were established. The result shows that the content of three heavy metals (Cu, Zn, Cr) in the leaves of Miscanthus floridulus is effective (R2>0.93) in modeling the spectral feature change of Miscanthus floridulus leaves under the severe impact of heavy metals.
With Yucheng County in Shandong Province as the study area, the authors estimated the LAI based on HJ-1 data and calculated four vegetation indices (NDVI, RVI, SAVI, EVI) to analyze their relationship with the observed LAI. A comparison of the four models has proved that the relationships between LAI and the four vegetation indices are all acceptable, and RVI seems to be the best parameter for estimating LAI (LAI=2.967ln RVI-1.201). With the RVI-LAI model, LAI map of Yucheng was retrieved in May 2009, with the average error being 19% or so, which suggests that the model achieves a high precision.
With Multinational Autonomous County of Longlin in Yunnan Province as the study area and on the basis of previous studies, this paper has proposed the utilization of the remote sensing information extraction method based on vegetation coverage through interactive interpretation of CBERS-02B multi-spectral data. The purpose lies in eliminating non-rocky desertification areas in the image such as the shadow, water area, bare soil and arable land so as to obtain the current distribution of rocky desertification in the study area. The method has been proved to be effective in extracting the distribution of rocky desertification in the study area, with no need of calculating and estimating such complicated parameters as the leaf area index.
Based on an analysis of the spectral characteristics of surface objects and using ETM remote sensing image,the authors utilized PCI software and employed the mask technique to remove various kinds of disturbance information such as white mud ground,water body, shadow and vegetation. With principal component analysis, band ratio and threshold segmentation techniques, the information of iron staining and hydroxyl alteration in Qangdoi area of western Tibet was extracted. In accordance with the obvious anomalous areas, the reference spectra were built up. The method of spectral-angle mapper was used to remove the pseudo-anomaly information. In conjunction with the characteristics of linear structure in the study area, the metallogenic prognosis was carried out and,as a result, the prospect areas were delineated. The method for metallogenic prognosis proposed in this paper is fairly flexible and effective,and can provide a reference and effective way for speeding up the geological exploration work in future.
The analysis of the characteristics of rocks and minerals constitutes the physical foundation of remote sensing exploration and rock recognition. In order to understand the spectral features more completely, the authors tested five different igneous rock samples from Xinchang area and analyzed their emission spectra. On the basis of emission characteristics of normal minerals and radicals, the authors analyzed the curves and obtained the location, depth, width, depth/width ratio, area and symmetry of the low emission bands by using the continuum removal method. The relationship of composition, alteration characteristics and associations of minerals to remote sensing spectral characteristics as well as its formation mechanism are also discussed in this paper.
Based on remote sensing interpretation symbols of faults, the authors interpreted and analyzed all faults along the Xintian Junction to Wuyishan Fenshuiguan segment of the Ningwu Superhighway. There are 5 large fault zones and 28 small-sized faults near the proposed superhighway route. In combination with the preliminary verification data, this paper established the evaluation indexes for faults affecting the stability of the route, so as to analyze and evaluate the specific impact of NE-, NEE- and NW-trending faults in the corridor belt on the proposed route. The results show that the evaluation indexes can improve the recognition of faults and provide quantitative parameters for route selection and road construction.
CEBRS-02B launched successfully on September 19, 2007 by China is a new earth resource satellite. The satellite remote sensing technology can play an important role in national economical construction. In order to improve the application of satellite remote sensing data in China, this satellite was used to extract the cole area in Luoping County of Yunnan Province so as to establish a reliable basis for the recognition of the cole area in Yunnan. Using the spectral analysis method, the authors analyzed the spectral reflectance properties of cole and then built a model for remote sensing cole feature extraction. The result shows that the extraction technique can provide references for condition monitoring and yield estimation.
Located in Wuhai City of Inner Mongolia, the Wuda coalfield is the biggest coal fire area in China. Between 2006 and 2008,shallow open-cut surface mining in the Wuda coalfield was conducted,with more than 2 000 million tons of coal excavated and more than 70% of the original landscape replaced by countless huge excavated pits and chip ballasts. If heavy rainfall occurred in the summer of 2009,the severely damaged coalfield would encounter floods,which would severely affect the safety and production of the coal mine. The relevant authorities paid a close attention to this problem. Using remote sensing (RS),Global Positioning System (GPS), Geographic Information Systems (GIS) and other new technologies in combination with some field work, the authors obtained a lot of investigation data and submitted an assessment report on the flood risk within 3 months. This is a successful practice of the application of 3S technology to the coal mine production.
The problem how to combine the low precision urban land use cover classifiers to get higher precision is dealt with in this paper. Using 2007 Shanghai CBERS (China-Brazil Earth Resources Satellite) images, the authors adopted the AdaBoost combination classifier, which can combine spectral feature information, texture structure information and decision tree classier to improve the classification precision. The experiment results show that a notable improvement of the classification precision of urban land use cover can be achieved by using AdaBoost algorithm.
Land use and cover changes are remarkably characterized by the temporal evolution and spatial differences. Comprehensive studies of these characteristics are very important for understanding the structure of land use and the trend of urbanization. With the support of the remote sensing and geographical information system (GIS) techniques, the authors incised a width of 5km along the Huangpu River coast as the study area from the Landsat TM/ETM+ images of Shanghai in 1992 and 2008. Moreover, for a comparative analysis, the study area was segmented into four subareas with the inner and exterior ring roads of Shanghai City. The two images were classified by using the minimum distance classifier in Envi 4.2 to map the land use. Several indexes, such as land use dynamic degree, intensity and relative change rate, were calculated to describe the land use changes. With the spatial analysis functions for the graphic in a GIS environment, newly increased builtup area were mapped to qualitatively analyze the spatiotemporal evolution of land use in Huangpu River coast. This study has demonstrated that the builtup area was greatly increased, the gardened area was slightly raised, and the cultivated land was drastically decreased in Huangpu River coast form 1992 to 2008. At the same time, the land use dynamic degree and the intensity of the eastern area were larger than the indexes of the average values of the whole Huangpu River coast.
Based on the landscape pattern theory, this paper made use of the TM remote sensing images of northern mountain areas of Mianzhu obtained before and after the Wenchuan May 12, 2008 earthquake for the work of land use classification. With the land-use classification map as the data source, the authors studied the disturbance of the earthquake to the landscape pattern in the aspects of classification and landscape level, and discussed the dominance, shape index and degree of fragmentation in different classes on the basis of FRAGSTATS software. The result shows that the woodland was most greatly affected, as evidence by the facts that its dominance was decreased, its degree of fragmentation was raised, and the edge effect was increased by the increasing edge density. In addition, the area of bush-wood and hilly dry field was deduced evidently, and the circulation and CONTAG of the landscape were decreased. In a word, the stability of the ecosystem is worse than that of the pre-earthquake period.
In this paper, Wuhan City was selected for case study. Land use information obtained from satellite remote sensing TM image in 2000 and 2005 was used as the main data source, and the GIS technology was employed as the data integration analysis platform. An ecological risk index was constructed based on the varieties of land use, and the systematic sampling method was utilized to make it a spatial variable. After the performance of sampling, the semivariagram analysis and block kriging were conducted to compile the map of ecological risk distribution. The results indicate that the spatial distribution of ecological risk became more uneven in the working area. The level of the ecological risk study area was divided into three levels: the majority of the vegetation and the waters belonged to the low ecological risk area, whereas the urban built-up area and its marginal areas belonged to moderate ecological risk and relatively high risk areas. Spatial distribution of areas of various levels experienced certain extent of changes in the five years.
Supported by remote sensing and GIS technology, the authors quantitatively evaluated the volume of soil
loss and the soil loss intensity in Xuanhua County in 2000 on the basis of RUSLE model, and made a characteristic
analysis of the spatial distribution of soil loss in this county. The results show that the soil erosion area (with
the erosion stronger than mild erosion) of Xuanhua County in 2000 was 982.85 km2, accounting for 39.25% of the
total area of Xuanhua County. The average soil erosion modulus was 13.92 t•hm-2•a-1, belonging to mild erosion. The
steeper the slope, the more probably the strongest erosion happened. On the whole, the slope belt of 15°~25° was
the belt subjected to the largest proportion of eroson. Soil erosion in Xuanhua County is mainly concentrated on
the irrigation grassland and the dry land, and the soil erosion area of these two land types in Xuanhua County
accounted for 93.897% of the total soil erosion area in 2000.
Based on the TM remote sensing images obtained in Guyuan County of Hebei Province in 1998, 2003 and 2008
and the landuse map as well as field data of the study area , the authors analyzed the spatial and temporal
patterns for dynamics changes of the vegetation cover in Guoyuan County in the past ten years by using the
dimidiate pixel model and expert classifier and consulting the statistical data with the purpose of understanding
the situation of ecological control The results show that most areas were in the moderate and relatively high cover
in the three monitoring periods, with the vegetation cover being improved in general. The condition of vegetation
cover was stable between 1998 and 2003, and was improved between 2003 and 2008. The areas with slightly increased
vegetation cover was mainly distributed in the plateau farmingpasture area, and the stable areas were mainly
distributed in the southern low mountain areas. The effect of the regulation project is remarkable.
The construction of the field investigation map is an important task which can guarantee the smooth
performance of field survey so as to obtain complete and reliable data. This paper has dealt with the drawing of
the field investigation map in mine monitoring by using ArcGIS, proposed a comprehensive mapping program and
analyzed the important problems and difficulties encountered in the construction of such a map.
Bing Maps can provide plentiful and free data resources. The convenient utilization of these resources is
a problem of wide concern. In many applications, it would cost much money and plentiful human resources to develop
software systems for managing the data, and the systems based on browser fail to support frequent user interaction
and data inter-operation. Web service provides an effective way to inter-operate geographical information through
platform and programming language. Based on analyzing the coding theory of Bing Maps tiles data and the structure
of the URL, this paper has introduced a method for approaching Bing Maps tiles data, and then implemented Web Map
Service (WMS) by using these data so that it can be loaded by any client which supports WMS. This method has
achieved the goal of convenient acquirement of map data and image data with less cost.