最新刊期
2009 年 第 13 卷 3 期
- 摘要：NO2是主要的大气痕量气体,对流层NO2垂直柱密度分布图已经用于诸如污染排放和污染物分布的科学应用研究。就NO2柱浓度的卫星差分光谱吸收反演算法（DOAS）进行了评述,包括误差分析、验证和发展趋势。对DOAS算法中的主要技术环节进行了详细的阐述,如ring效应算法、平流层NO2浓度算法和大气质量因子（AMF）问题。论文描述了影响卫星反演NO2浓度,如云、NO2廓线的先验数据和气溶胶等不确定性因素。针对NO2反演应用需求提出了今后应该加强的内容,如进一步加强NO2算法研究、发展空气质量探测的静止卫星、重视基于地基多轴被动DOAS和机载平台成像DAOS观测对卫星反演结果的验证。关键词：NO2;SCD;VCD;AMF;对流层;DOAS
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发布时间：2021-06-10
综述
- 摘要：Space-borne microwave radiometer plays an important role in retrieving geophysical parameters of the global ocean surface.The Advanced Microwave Scanning Radiometer（AMSR-E）,launched on May 4,2002 aboard NASA’s Aqua spacecraft,is a passive microwave sensor that precisely measures microwave emission from the earth surface and atmosphere with multiple frequency bands.AMSR-E can measure a series of oceanic parameters,such as atmospheric water vapor,cloud liquid water,precipitation,sea surface wind,sea surface temperature,sea ice,snow cover,and soil moisture.In this paper,an ocean surface microwave emission/scattering algorithm and an atmospheric radiation algorithm are developed for retrieving geophysical parameters from AMSR-E brightness temperatures.Sea surface wind,sea surface temperature,water vapor,and cloud liquid water of global ocean are retrieved.The results are validated by NCEP reanalysis data,as well as TAO buoy data on the Pacific Ocean.The retrievals are also compared with those from Wentz2000 algorithms for evaluating accuracy of the algo-rithm.It is found that there are excellent correlations between the in situ parameters and those retrieved from either statistical algorithms or physical algorithms.It is also found that there exits system biases in all retrieved parameters which can be well corrected by a linear equation.The results compared with NCEP’s are different from those with TAO’s,which may results from the uncertainties in NCEP data.The final RMS error of sea surface wind,sea surface temperature are 1.21m/s,0.73K,respec-tively,comparing with TAO ’s.
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发布时间：2021-06-10
Fundamental Research
- 摘要：从微波辐射传输原理出发,通过理论模拟的亮温建立了海洋和大气参数的反演算法,利用AMSR-E数据进行地球物理参数的反演验证,并利用Wentz算法进行相同参数的反演,以判断反演的效果。研究表明:在使用各种方法进行参数反演的时候,反演结果和实际值之间存在很好的相关性,但是都存在一个系统偏差需要修正。通过与NCEP和TAO浮标两组数据的比较发现,同样的算法反演结果的均方根误差不同,采用浮标数据比较的反演结果明显好于NCEP数据,原因可能是NCEP数据存在一定的不确定性。算法反演大洋海面温度和风速的均方根误差分别为0.73K和1.21m/s。关键词：星载微波辐射计;AMSR-E;反演算法;海洋大气参数
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发布时间：2021-06-10
基础理论
- 摘要：In this paper,a method to evaluate the in-flight MTF（Modulate Transfer Function） of the WFI（Wide Field Imager） on CBERS-02B is presented and the WFI images are restored.The CCD is another payload on CBERS-02B with high spatial resolution.Using the CCD images as high resolution images,the two-image comparison approach is applied to determine the MTF of the WFI with a pair of images acquired over Beijing on Nov.10,2007.As the results,MTF values in three directions are derived.The MTF values at Nyquist frequency in cross-track,in-track and 45° directions were respectively about 0.43,0.52 and 0.35 for red band and 0.30,0.46 and 0.36 for near-infrared band.Image-derived MTF values are applied to calculate the half bandwidths of the WFI.The results indicate that the instant fields of view of the WFI in the cross-track,in-track and 45o-track directions were respectively 1.188 pixels,1.165 pixels and 1.281 pixels for red band,and respectively 1.258 pixels,1.195 pixels and 1.326 pixels for near-infrared band.Weiner filter model is used to perform the MTF compensation for WFI images.The re-sults show that the restored image seemed clearer and contained more detailed information.
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发布时间：2021-06-10 - 摘要：An inversion method of bridge height over water surface is developed.A geometric rays description is illustrated for scattering mechanism of bridge over water surface.Based on Mapping and Projecting Algorithm（MPA）,polarimetric SAR images are simulated and the results show that the bridge in SAR image can be identified by three strips corresponding to single-,double-and triple-order scattering,respectively.A set of parameters based on de-orientation theory is applied to locate the im-aging positions of single-,double-and triple-order scattering of the bridge body.The thinning,clustering algorithm,and Hough transform are employed to detect the lines indicating different orders of scattering.Then,these lines are used to invert the bridge height.Fully polarimetric data of airborne Pi-SAR at X-band is applied to inversion of the Naruto Bridge height and width.Based on the same principle,spaceborne ALOS PALSAR data of the Eastern Ocean Bridge is also applied to the bridge height inversion.The results show good feasibility of the bridge height inversion.
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发布时间：2021-06-10 - 摘要：In order to meet the increasing demand for SAR raw signal and SAR images simulation,a new method for the simulation of the SAR raw signal and images of typical terrains is proposed in this paper.The properties of Fractal Brown Sur-face and its horizontal are analyzed first.Then the Digital Elevation Model（DEM） of the mountain terrains is generated by the usage of random MPD（Middle Point Displacement） method.The new approaches for the generation of coastal terrain（Re-turn-to-Zero method） and river-ravine terrain（Return-to-Zero-Inversion method） are also proposed.The back scattering coeffi-cient of each resolution cell is calculated by employing the corresponding electromagnetic scattering model.The algorithm of SAR raw signal simulation based on the 2DFFT（two-dimensional Fourier Transform） is presented.The simulation results show that the proposed method is valid.
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发布时间：2021-06-10 - 摘要：Diffuse attenuation coefficient of downwelling irradiance at 490nm,Kd（490）,is one of the important ocean optical properties.The retrieval model is of great interest especially for the optically complex water,where terrestrial influence on ocean optical properties is significant.Comprehensive bio-optical dataset were acquired in the nearshore area of the Bohai Sea in 2005.Statistical retrieval model for Kd（490） based on remote sensing reflectance spectra is developed.The model is validated by in situ data with the Absolute Percentage Difference（APD）,Root Mean Square error（RMS,in log10 scale） and Pearson correla-tion coefficient（in log10 scale） of 18.4%,0.094 m-1 and 0.902 respectively between in situ and retrieved Kd（490） values.Error performance of the model is analyzed and it is shown that APD of the retrieval is better than 30% for 76% of all the in situ data.Model’s sensitivity to the input noise is analyzed by imposing ±5% error of remote sensing reflectance spectra artificially,which proves that the model is robust and reliable with the error fluctuation of model output being less than 9% for APD and 0.035 m-1 for RMS.The model is applied to ENVISAT MERIS data to give the spatial distribution of Kd（490） of the Bohai Sea.
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发布时间：2021-06-10 - 摘要：From repeat pass SIR-C L band polarimetric SAR interferometric data and fully maximum likelihood inversion decomposition model of PolInSAR,a method for sub-canopy soil moisture estimation using repeat pass SIR-C PolInSAR data is proposed.At the same time,the potential and validity of fully maximum likelihood inversion decomposition model of PolInSAR for sub-canopy soil moisture inversion is investigated.Firstly,from the random oriented volume over ground two layer coherent scattering model and the statistical characteristics of Pol-InSAR coherency matrix,the fully maximum likelihood inversion de-composition model is used to reconstruct or recover the surface polarimetric coherency matrix with volume scattering compo-nents significantly removed;then,from recovered surface polarimetric coherency matrix,co-HH,VV and cross-HV polarization backscattering coefficient are obtained,and the sub-canopy soil moisture are inverted from Oh and Dihedral scattering model.At last,Compared the inversion result with the field measurement and the climate data of hetan region from 1951 to 2006,the pre-liminary result indicates that the proposed method based on fully maximum likelihood inversion decomposition model has enough high inversion accuracy,if the new spaceborne or airborne polarimetric SAR interferometric data with synchronously spaceborne or airborne-ground measurement will be acquired,the validity and accuracy of proposed inversion method will be further investigated and validated.
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发布时间：2021-06-10 - 摘要：In this paper,the P-SVM algorithm was introduced into multi-spectral/high-spatial resolution remotely sensed data classification and it is applied to classification of ASTER satellite data and ADS40 aerial digital data.The experiments indicate that the P-SVM is at least competitive with the standard SVM algorithm in classification accuracy of remotely sensed data and the time needed is less.
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发布时间：2021-06-10 - 摘要：High accuracy surface modeling（HASM）constructed based on the fundamental theorem of surface is more accu-rate than the classical methods.However,because of boundary error,location error,etc,HASM has a big accuracy loss in real-world examples.In former researches we solved the location error with Taylor expansion.In order to reduce the HASM boundary error and improve its accuracy further,this paper presents a new method of Laplace interpolation to compute the re-gion boundary value.Gaussian synthetic surface and the real world test region are employed to validate the efficiency of this method.Results show that the boundary value computed with Laplace interpolation is more accurate than the classical methods,which can be regarded as an alternative for boundary value computation.
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发布时间：2021-06-10 - 摘要：MWRI（MicroWave Radiation Imager） is one of the payloads on our next generation polar meteorological satellite FY-3.MWRI conically scans with a fixed incident angle on the earth surface.It is the first time for Chinese remote sensor to use this scan mode.In this work,we present a geolocation method for FY-3 MWRI’s remote sensing image based on its special scan geometry.The integrated coordinate systems and the specific relationships with these coordinate systems are defined.A spatial relationship model between the remote sensing data and the earth-based coordinate system is established.This method also in-cludes an algorithm of satellite orbit computation,which is used to get the satellite’s instantaneous velocity vector from its posi-tion.This method has been applied to MWRI’s remote sensing image geolocation.The results show that the accuracy of this method can achieve 1 pixel.The 33 GCPs（Ground Control Points） which are in the regiones of FY-3 MWRI’s observation have been collected and used to analyze the precision of the geolocation.By statistical analysis,the error along-track is about 1.5km,and the error along-scan is about 3.0km.It is obvious that this method fulfills the requirement of precision for FY-3 MWRI whose space resolution exceeds 5km.
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发布时间：2021-06-10
Technology and Methodology
- 摘要：基于高分辨率图像对比法,利用同一卫星平台上空间分辨率19.5m的CCD相机图像对CBERS-02B卫星上空间分辨率为258m的WFI成像仪图像进行在轨MTF（modulate transfer function）测量,获得WFI（wide field imager）相机沿轨、跨轨与45o方向的MTF曲线,并计算出3个方向的线扩展函数LSF（line spread function）,获得3个方向的有效半带宽。结果表明WFI相机红波段跨轨、沿轨与45o方向的有效半带宽,即有效瞬时视场,分别为1.188,1.165与1.281个像元,近红外波段为1.258,1.195与1.326个像元。基于获得的MTF,利用维纳滤波法对WFI图像进行补偿,部分恢复了WFI图像的细部信息。关键词：CBERS-02B;CCD;MTF;高分辨率图像对比法
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发布时间：2021-06-10 - 摘要：提出一种SAR数据检测桥面高度的反演方法。用几何射线描述桥梁散射机制,依据去取向理论和分类参数分析,得到SAR成像中桥梁结构目标单次、二次、三次散射的成像规律。通过SAR图像分类参数的聚类与细化、滤波和Hough变换直线检测算法,检测出单次、二次和三次散射回波所成位置线图像,进一步构成桥面高度的反演算法。用机载Pi-SAR数据反演了日本鸣门大桥的桥面高度和桥面宽度,并与实测数据对比。按照该方法,进一步采用星载ALOS-PALSAR数据检测中国东海大桥的桥面高度。反演方法是可行的。关键词：SAR;桥高反演;Pi-SAR;ALOS-PALSAR
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发布时间：2021-06-10 - 摘要：SAR成像算法的验证需要相应的回波数据,同时SAR图像目标识别算法的检验需要大量的SAR图像,针对这一要求,提出了一种典型地形SAR回波模拟与图像仿真的方法。首先分析了分形布朗曲面及其水平集的特征。在此基础上,运用中点位移法生成了描述山脉地形的数字高程数据,提出了生成海岸地形（"归零法"）及河流沟壑地形（"归零取反法"）的新方法。引入电磁散射模型,计算了每个分辨单元的后向散射系数。给出了基于二维快速傅立叶变换的SAR回波模拟算法的推导过程及相应的仿真结果,并对结果进行了分析和讨论,证明了该方法的正确性。关键词：回波模拟;合成孔径雷达;分形布朗曲面;随机中点位移法
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发布时间：2021-06-10 - 摘要：利用2005年渤海近岸水体生物光学数据集,建立了基于水体遥感反射率光谱Rrs（λ）数据的490nm波段水体漫衰减系数Kd（490）经验反演模型,经实测数据检验,模型反演结果的平均相对误差为18.4%,均方根误差（对数坐标下）为0.094m-1,相关系数R2（对数坐标下）为0.902。分析了模型的噪声敏感性,在输入端引入±5%误差的情况下,模型反演结果的平均相对误差波动在9%以内,均方根误差的变化在0.035m-1以内,模型是稳定可靠的。以ENVISAT MERIS数据为例,进行了模型的示范应用,给出了渤海Kd（490）的空间分布。关键词：渤海;漫衰减系数Kd（490）;遥感反射率;反演模型
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发布时间：2021-06-10 - 摘要：提出了一个针对重复轨道SIR-C数据的极化干涉SAR植被覆盖地表土壤水分反演方法,同时,探讨和分析了极化干涉SAR最大似然反演分解模型在植被覆盖区土壤水分反演中的潜力和有效性。利用极化干涉SAR最大似然反演分解模型重建消除了体散射分量的植被覆盖下地表极化相干矩阵;计算同极化和交叉极化地表后向散射系数,并利用Oh模型和二面角（Dihedral）散射模型估算植被覆盖下地表的土壤水分;将反演的植被覆盖下地表土壤水分结果与野外实测土壤水分结果和该区域1951—2006年的气候数据进行比较和分析,初步结果表明:基于极化干涉SAR最大似然反演分解模型的植被覆盖区土壤水分反演方法得到的结果具有足够高的估计精度。关键词：极化干涉SAR;植被覆盖地表;最大似然反演分解模型;土壤水分估计
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发布时间：2021-06-10 - 摘要：本文介绍了将P-SVM算法引入多光谱/高分辨率遥感数据的分类,并且展示了卫星ASTER和航空ADS40数字影像分类的技术过程和结果验证。结果表明:P-SVM方法的分类精度不低于SVM,并减少了时耗。关键词：SVM;P-SVM;多光谱/高分辨率遥感数据;遥感数据分类
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发布时间：2021-06-10 - 摘要：为了降低模拟区域边界误差的影响,进一步提高HASM插值精度,提出借助Laplace方程来模拟区域边界。用此方案计算高斯合成曲面边界,直接验证该方案的插值精度;选取山东省临沂市某试验区作为研究对象,模拟该区域的高程异常曲面,间接验证该方案的可行性。数值模拟结果表明,使用Laplace方程计算的模拟区域边界精度较高,且大幅度提高了HASM实际应用的插值精度。关键词：曲面建模;精度损失;Laplace方程;误差
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发布时间：2021-06-10 - 摘要：风云3号（FY-3）微波成像仪采用天线绕轴旋转形成圆锥形跨轨的扫描方式。该研究依据这种特殊的扫描几何,给出了适用于FY-3微波成像仪遥感图像地理定位的方法。根据微波成像仪观测几何、仪器空间位置和指向建立了遥感图像观测像元与地面位置之间关系的模型,其中包括根据卫星位置计算实时速度的算法模型。将此方法用于FY-3微波成像仪遥感图像地理定位,将计算结果与实际遥感图像比较以及通过地面控制点定位精度统计分析,使用该方法的地理定位精度达到像元级。关键词：微波成像仪;圆锥扫描;观测几何建模;遥感图像地理定位
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发布时间：2021-06-10
技术方法
- 摘要：As the rapidly growing of availability of high-resolution urban SAR images,analysis of urban environments using SAR images has become an important task in the field of SAR image interpretation.Built-up areas are the dominant structures of urban environments.Detecting and analyzing built-up areas has attracted more and more attention of researchers interested in urban SAR image interpretation.In this paper we propose a method of detecting built-up areas from high-resolution SAR images using the GLCM（Gray-Level Cooccurrence Matrix） textural analysis.Our method is composed of two stages:initial localization of built-up areas and boundary adjustment.Both stages follow a flow of feature computation,Bhattacharyya-Distance-based feature selection and KNN（K-Nearest Neighbor） classification.The difference is that a block-by-block feature computation manner is used in the first stage while a pixel-by-pixel one is used in the second stage.Experiments are performed on images obtained by different SAR sensors.The results indicate that the best three or four features,which have the highest Bhattacharyya distance,lead to the high performance of initial localization,with detection rate higher than 80% and false alarm rate lower than 10%.With the boundary adjustment is implemented,the detected built-up-area boundaries gradually get close to the real boundaries.The experimental results of different SAR images show that the proposed method for built-up area detection is promising.
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发布时间：2021-06-10 - 摘要：Although drastic land use change took place rapidly in very short interval in the Pearl River Delta of China,hardly any research has been done on this for lacking of available data.Located in the south of China,Pearl River Delta suffers from heavy cloud cover for more than half of the year.This makes real-time land use-land cover change（LUCC） monitoring almost impossible using optical remote sensing images.In this paper,the orbital highest resolution SAR（Synthetic Aperture Radar） data-Fine Mode Radarsat data is selected and three scenes of repeat-pass Radarsat images are used for short-term land use change detection.Short-term land use change caused by human activity is considered as spatial and temporal abnormal in time series images.And a Density-Based Anomaly Detection（DBAD） algorithm is designed to detect abnormally changed land par-cels in time series Radarsat images.After that field survey data are used for validation.The result shows that DBAD gained bet-ter accuracy in comparison with object-based image regression method.Besides,DBAD exhibits greater capabilities in detecting under-constructed area and newly built up area（with error lower than 12%）.While for built up area and some mixed used area,DBAD gained relatively lower accuracy（with error from 10% to 28.57%）.
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发布时间：2021-06-10 - 摘要：Cloud tracking technique based on the combination of Fourier phase analysis and maximum correlation（TCFM） is employed to retrieve cloud motion vectors for sever tropic storm "Masta" from geostationary meteorological satellite FY-2C image series with a 30min interval on August 5,2007.The retrieved data are assimilated into the numerical model ARPS（the Advanced Regional Prediction System） by means of its data analysis system ADAS for the period before "Masta" landed onto ground.Though conventional wind observations are rare over sea areas,the experiment with satellite-derived winds from TCFM technique shows that the cloud motion wind data can improve the vertical wind features in the east of eye wall and make the helical rainband more realistic.
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发布时间：2021-06-10 - 摘要：Irrigated land is one of the most important parts in land cover classification system,but until now it has seldom been reported about extracting it from remote sensing data and monitoring its dynamic change.The existing researches are focused on the land use-cover change（LUCC） and the irrigated area mapping,so the study on extracting irrigated land is much more im-portant.On the basis of close relationship between water deficit index（WDI） and soil water content,this paper firstly combines two neighbor NDVI and the surface-air temperature（Ts-Ta） and conforms one Vegetation Index Temperature（VIT）.It makes the timely incomparable WDI comparable and then computes the change of WDI during the monitored period.Secondly it infers the change of soil water.Thirdly it removes the rainfall’s influence under some assumption and extracts the irrigated land of the survey area.Results show that comparing with census data all the deviation is below 7% in the survey area except Shanxi prov-ince,which means that the extracted results are comparable with census data.Extracted irrigated land mainly distributes around rivers,lakes,and reservoirs or on the irrigated regions and oasises.The results are consistent with the centralized region which has abundant irrigated land known before.The results are checked elementarily using TM images.All the precisions are above 70% except in Shanxi province.The precision in Xinjiang municipality is the highest.
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发布时间：2021-06-10 -
Automatic extraction of forest fire line using MODIS data by multi-spectral image gradient technique
摘要：Remotely sensed infrared images are often used to assess forest fire conditions.Meanwhile,fire propagation mod-els are in use to forecast future conditions.The traditional method of fire monitoring is mapping or extraction of burn scar and hotspot generally depending on abnormity character of spectral radiation and thermal infrared（TIR） channels.In the Dynamic Data-Driven Application System（DDDAS） concept,the fire propagation model will react to the image data,which should pro-duce more accurate predictions of fire propagation.So the parameters of fire line and propagation direction extracted from the fire edge map are more important than burnt area estimation in real-time fire forecast application.The method capable of auto-matically determining the fire perimeter,active fire line,and fire direction is developed in this paper based on some image proc-essing techniques.And MODIS（Moderate resolution Imaging Spectrometer） is used as experimental data because of its widely spectral range bands and dynamic monitoring capacity for the earth.First,the optimal bands choice construction for spectral in-dices of NDBR（Normalized Difference Burn Ratio） capable of describing active fire intensity is discussed.Then the multi-spectral image gradient together with TIR channels and solar reflectance channels is used to map the fire edge which can be put on NDBR image for restriction against active fire line.And B-spline model is applied to fit fire line segments to a spline curve for fire propagation front estimation by normal of the spline.At last,the kriging interpolation method based on hotspots with high gradient magnitude of fire line is used to extrapolate fire edge region to validate these results.The image of forest fires located in Great Xing’an Mountains is processed and another image after 30mins is used as the referenced image.Two aspects prove that propagation of fire line are essentially consistent with the referenced image.And expectation,entropy value of image context and kappa for spatial fire pixel identification can respectively reach 86%,81%,80.2% compared with the referenced one.So it is suggested by the results that this automatic process for extracting fire propagation parameters can be proved with well performance and efficient in dynamic fire mapping and monitoring.- 137
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发布时间：2021-06-10 - 摘要：Noise estimation plays significant role in payload assessment,image processing and data application.In this paper,considering characteristics of Beijing-1 small satellite,the image-based noise estimation methods with their applicability are ap-praised and compared through experiments.The parameters and model optimization are also discussed for better assessment of noise.With comprehensive analysis of noise estimation results from different land cover types,the Beijing-1 small satellite noise is evaluated with its standard deviation.Comparison of the noise estimation from images acquired in 2008 and the in-orbit test right after launch in 2005 shows that noise level of the Beijing-1 small satellite does not change,the satellite has well-kept per-formance even after 3 years of operation.
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发布时间：2021-06-10
Remote Sensing Applications
- 摘要：根据高分辨率SAR图像上建筑区的影像特征,提出了基于灰度共生矩阵（gray-level cooccurrence Matrix,GLCM）纹理分析的建筑区提取方法,该方法由初步定位和边界调整2个步骤组成,均遵循特征计算、基于Bhattacharyya距离的特征选择和KNN分类流程,所不同的是2个步骤中分别采用了逐块和逐点计算纹理特征的方式以兼顾纹理分析的效率和准确性。文中对不同SAR传感器获取的图像进行了实验。实验结果表明,选用具有最大Bhattacharyya距离值的3或4个特征可以获得较好的初步定位结果,建筑区的检测率超过80%,虚警率低于10%;随着边界调整的进行,检测到的建筑区边界逐渐接近于真实边界。实验结果验证了该算法的有效性。关键词：纹理分析;灰度共生矩阵;合成孔径雷达;建筑区检测;特征选择
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发布时间：2021-06-10 - 摘要：论文分析了时间序列遥感影像中土地利用/土地覆盖短期变化的特点及其时空异常特征,认为和环境、物候等因素造成的影像变化相比,由人为活动引起的土地利用/土地覆盖变化具有典型的时间和空间异常特征,并提出了基于密度异常的土地利用短期变化检测方法。研究工作选取珠江口地区1—5月作物生长期间的3个时间序列Radarsat雷达影像进行试验,在影像分割的基础上,构建了基于对象的特征变化矢量,并将密度异常检测算法（DBAD）扩展到变化矢量的N维特征空间上,运用随机搜索策略确定检测参数,对Radarsat时间序列变化矢量中的"小模式"事件进行了检测。检测结果认为,密度异常检测算法检测的是变化矢量在特征空间的密度分布,与变化矢量的强度和方向无关,因此能在时间序列影像中分离出由典型的、正常的作物生长或农事活动引起的影像光谱或回波变化,进而识别出由人为活动或突发事件导致的土地利用/土地覆盖变化,这是通常的图像差值等方法难以做到的。进一步的抽样检测说明,密度异常检测方法对新增建设用地的检测准确率最高（>88%）;林地地表覆盖相对稳定,检测误差也很低（8%）;农用地和养殖水面的异常变化检测误差在11%—22%之间;较大的检测误差主要集中在建设用地、农用地和未利用地之间的转换（16%—25%）;此外,养殖水面的检测误差主要集中在河流沿岸及水面变化较大的养殖区域。影像分割结果特别是一些线状分割图斑以及混合地类图斑对误差也有一定的影响。关键词：土地利用/土地覆盖;短期变化;变化检测;密度异常检测
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发布时间：2021-06-10 - 摘要：利用傅里叶相位分析方法与最大相关法结合的云导风技术TCFM（Technique based on combination of Fourier phase analysis and maximum correlation）,对2005-08-05的强热带风暴"麦莎"天气过程中静止气象卫星得到的30min间隔云图时间序列进行导风计算,并将导风结果应用于中尺度数值模式ARPS（The Advanced Regional Prediction System）,结合其资料分析系统ADAS（ARPS Data Analysis System）,对台风"麦莎"登陆前的过程进行模拟。尽管洋面上常规资料稀缺,但卫星导风数据的同化使用结果表明,TCFM技术得到的导风资料能够显著改善台风眼壁东部区域的垂直气流活动,使台风螺旋雨带更加明显,符合实际。关键词：TCFM导风技术;云风矢量;资料同化;台风模拟
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发布时间：2021-06-10 - 摘要：水浇地是土地覆盖分类系统中的一个重要类型,依据水分亏缺指数（WDI）与土壤水分的相关性,计算了监测时间内WDI的变化情况,用降雨资料去除了由于降雨引起的WDI的变化,进而提取了研究区的水浇地分布。结果表明:（1）提取出的水浇地在数量上与统计资料相比,除山西省偏差相对较大外,其余各省偏差均小于7%,提取出的结果与统计资料具有可比性。（2）提取出的水浇地在空间上多成片出现在河流、湖泊、水库附近、灌区和绿洲上,与已知的水浇地集中区一致。（3）利用TM影像对提取结果进行了初步判断,其中山西省的正确率较低,只有64%,其余各省正确率均在70%以上,新疆的正确率最高为92%。关键词：水浇地;土地覆盖;水分亏缺指数（WDI）;MODIS数据;HANTS变换
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发布时间：2021-06-10 - 摘要：结合归一化火灾差异指数NDBR（normalized difference burn ratio）和MODIS多波段影像梯度边缘分析手段检测火线,应用B样条函数拟合火线并确定火势蔓延方向。为对比验证,基于火线的Kriging插值实现火灾外推预测,与30min后的火灾参考数据目视对比与统计:火线的预测变化与参考影像基本保持一致,火灾外推影像的均值和熵约为参考影像的86%和81%,火迹地检测的Kappa系数达80.2%。试验表明,提出的森林火线特征自动检测方法在动态火灾监测中是可行、有效的。关键词：MODIS;NDBR;多波段影像梯度;火线检测;Kriging插值
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发布时间：2021-06-10 - 摘要：从理论和试验方面对图像的噪声评估方法进行了分析。结合北京1号小卫星特性,进行了该类方法应用效能的评价,讨论了分块评估噪声方法的最佳参数设置。选取满足噪声评估环境的图像,实现了综合不同地表覆盖条件的北京1号小卫星图像噪声的评估。噪声评估结果与在轨测试情况的对比表明,北京1号小卫星经过近3年的运行,仍保持了较好的性能。关键词：噪声评估;北京1号小卫星;噪声标准差
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发布时间：2021-06-10 - 摘要：<正>为更好地适应期刊发展,推动遥感学科建设,拉近与广大作者的距离,密切与审稿专家间的联系,《遥感学报》网站现已开通运行。今后,学报的各项日常工作将陆续转到数字平台上,通过网站实现。针对学报读者、作者以及审稿专家,学报网站开设了多个定制在线业务系统:
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发布时间：2021-06-10
遥感应用
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