最新刊期
卷 16 ， 期 5 ， 2012
- 摘要：There still has some def iciencies in photogrammetric application with the existing geometric imaging model of radar imagery. In view of this situation the theoretical analysis was made f irstly in this paper. Then several equations were constructed in turn, including Range-Coplanar （R-Cp） equation with explicit function form of image point coordinate, Range-Coplanarity equation in geocentric coordinate system and rigorous positioning model based on R-Cp equation. At last some tests including rigorous positioning were done with spaceborne TerraSAR-X imagery and sparse ground control point. The theory and experiments show that the proposed R-Cp model embody the attributes of image measurement coordinate as photogrammetric observation value, which make it easy to absorb and utilize mature digital photogrammetric theory and methods developed on collinear equation model for optical remote sensing images. For data processing of radar imagery photogrammetry the model can overcome the shortcomings existed in other model and improve the rigor, stability, reliability and eff iciency.关键词：Range-Coplanarity （R-Cp） equation;side-looking radar;rigorous positioning;sparse control point;exterior orientation elements;combined adjustment
- 128
- |
- 386
- |
- 4
发布时间：2021-06-10 - 摘要：A new algorithm for mixed-pixel clumping index （MPCI） calculation is proposed, which is based on the directional gap fraction and linear mixture model from the high-resolution remote sensing data. In this algorithm, the scale difference caused by the spatial heterogeneity of the fraction of vegetation cover （FVC）, end-member clumping index （EMCI） and leaf inclination angle distribution （LAD） within the mixed pixel is well considered. The preliminary sensitivity analysis with the simulated data shows that the impact factors in a descending order are the special heterogeneity of EMCI, FVC and LAD （expressed as G function）. The maximum values of the relative variation ratio caused by the heterogeneities are about 55%, 43% and 12%, correspondingly. The results also demonstrate that it is very necessary and signif icant to correct the scale difference in the mixed pixel with high special heterogeneity. It is potential to improve the accuracy of coarse leaf area index retrieval by employing the MPCI algorithm presented in this paper.关键词：clumping index;mixed pixel;gap fraction;leaf area index;scaling;spatial heterogeneity
- 172
- |
- 761
- |
- 6
发布时间：2021-06-10 - 摘要：In order to improve the transmission bandwidth of digital image, the performance of fiber link, and the anti-interference ability of electromagnetic, a high speed optical f iber Transmission system for CCD image was designed in space CCD camera with a large f ield of view. First, the input rate was gained according to the characteristics of CCD imaging unit and the working environment of space camera in orbit, based on which, a 9-channel parallel high speed optical f iber transmission system for multi-channel CCD image was designed. Then, we expounded the system design idea and the principle of high speed serializer and optical module. Then, an error correction algorithm was proposed. And implementation method using very large scale integration （VLSI） was explained for the encoder. Finally, the experiments were performed for transmission system of the prototype in XX-X space multi-spectral camera. The results showed that the transmission system has a high reliability. The correcting algorithm has the characteristics of strong error detecting ability, less resource occupation and easier to be realized with hardware. The method is able to correcting 191 bit errors in 3043 Byte and meets the reliability of image Optical f iber transmission in space camera.
- 178
- |
- 462
- |
- 2
发布时间：2021-06-10 - 摘要：The atmospheric transmittance properties for three near-infrared channels of POM02 skyradiometer at the wavelengths of 1020 nm, 1627 nm, and 2200 nm, were studied by using a combined atmospheric radiative transfer model （CART）. Results showed that, the extinctions at the bands of 1020 nm, 1627 nm, which are located in atmospheric window channel, obeyed the Beer-Lambert law. For the 2200 nm channel located in an absorption band, the absorption exhibited an exponential distribution. Then these channels of POM02 skyradiometer were calibrated with traditional Langley method and modified Langley method, respectively. Two calibration methods were applied for four clear days. It proved that the accuracy of derived transmittance has been improved by 3.8% using modified Langley method to 2200 nm channel.关键词：Sun-photometer calibration;near-infrared;absorption band;modif ied Langley method
- 149
- |
- 451
- |
- 7
发布时间：2021-06-10 - 摘要：Inter-calibration method for infrared channels of geostationary satellite FY-2/VISSR is introduced using the high-spectral resolution sounder （HSRS） as a reference on board a polar orbit satellite, i.e., METOP/IASI or AQUA/AIRS. Analyses on its reliability were performed based on FY-2E historical data since 2009. The results indicate that inter-calibration results based on the two independent sensors IASI and AIRS have a good consistency between them, and the mean blackbody temperature （TBB） bias of HSRS inter-calibration is about 0.07 K with standard deviation of 1.4 K, which proves that there is no systematic bias and the distribution of TBB bias is approximately normal. Thereinto, the mean TBB bias is approximately less than 0.2 K and 1 K when TBB is great than 290 K and 220 K, respectively, and is about 0.3 K at a lower temperature. Comparing with the operational calibration provided in the Level1 f iles, HSRS inter-calibration shows obviously improvements. Longtime statistic analyses demonstrate the HSRS inter-calibration method studied here is stable and reliable, and its accuracy can meet the require-ment in quantitative applications.关键词：geostationary meteorological satellite;high-spectral resolution sounder;inter-calibration;infrared channel;spectral compensation
- 201
- |
- 598
- |
- 8
发布时间：2021-06-10 - 摘要：River network is a typical spatial entity in the real world and its multi-scale transformation is a hot issue in the field of cartography and geographical information science. This paper proposes a multi-scale transformation approach for river network, which is based on morphing technology. This approach involves two cases. One is to make transformation between two corresponding rivers, and the other is for some rivers represented only on the larger-scale map. As for the first case, shape interpolation is utilized for morphing, where the intersections between rivers and the structures of rivers themselves are considered. For the second case, an indicator is defined by the total length of a river and its tributaries, and is employed to measure the importance of the river. By this indicator, some rivers of low importance, which are represented only on the larger-scale map, may be deleted in the process of multi-scale transformation. Through the case study, it is shown that the approach proposed in this paper can improve the results of morphing between rivers as well as the accuracy of river selection in the process of multi-scale transformation.关键词：river network;morphing;multi-scale;shape interpolation;river selection;Cartographic generalization
- 188
- |
- 348
- |
- 6
发布时间：2021-06-10 - 摘要：Estimation of evapotranspiration （ET） is an obstacle in researches of both water and energy balance. In this paper, three-temperature （3T） model was revised for remote sensing application. A case study was performed in a semi-arid grassland from July to October in 2008 in Taibus Banner of Inner Mongolia, China. Eleven cloudless MODIS images at 1 km scale were used to estimate ET and data observed from two Bowen ratio systems in the corresponding period was adopted to validate the performance of the 3T model. Results showed that: （1） the modeled ET varied from 1.28 mm/d to 9.03 mm/d in the growing season, with a mean value of 4.58 mm/d; （2） the modeled daily ET distributed homogeneously in space, and temporally, ET value increased and then decreased gradually as the growing season changed from beginning to the end; （3） the mean absolute error between the observed and modeled ET was 0.58 mm/d, with maximum and minimum absolute errors of 1.64 mm/d and 0.11 mm/d, respectively, and the mean absolute percent error was 17.10%. All the performances indicated that the 3T model has a good potential in ET estimation.关键词：3T model;evapotranspiration;MODIS;Bowen ratio energy balance method
- 157
- |
- 895
- |
- 4
发布时间：2021-06-10 - 摘要：Leaf area index （LAI） is one of the key parameters that describe the plant physical structure. However, the LAI product is consistently discontinuous at spatial and temporal scales due to the contamination of atmospheric factors, which limits its application. In this paper, multi-year historical LAI datasets were used as a priori knowledge to establish the LAI background library, based on which, the improved Savitzky-Golay （SG） algorithm was designed to reconstruct the high quality LAI prof iles. The results indicated that by comparison with a traditional SG algorithm, the new algorithm performed better in aspects of both robustness and efficiency.关键词：LAI algorithm;time-series;background library;SG f ilter
- 226
- |
- 509
- |
- 4
发布时间：2021-06-10 - 摘要：Based on field measurements and the PROSAIL model simulations, this paper compared the new HJ-1A CCDs sensors data and the widely used TM data, and analyzed the effects of the sensors zenith angle and spectral response function （SRF）. We further compared the two sensors in estimating grass LAI and fresh biomass. The following conclusions can be drawn: （1） the adjusted coefficients of determination R 2 between HJ-1A CCDs and TM reflectance ranged from 0.7322 to 0.9205. The reflectance of the two sensors are very consistent while the absolute value is small, but as the grass cover faction increases, HJ-1ACCDs data is a little larger than TM. Overall, for the visible and near infrared bands, the HJ-1ACCDs image data is generally similar to the TM data. For HJ-1A CCDs and TM, the reflectance in red band showed the best correlation. （2） The normalized difference vegetation index （NDVI） of HJ-1A CCDs and TM are significantly correlated. Compared with reflectance data （with relative difference of 3.34%–9.54%）, NDVI is less affected （with relative difference of 0.34%–0.53%） by sensor zenith angle or spectral response function. （3） The sensor zenith angle was proved making a slightly greater impact on the sensor reflectance data than the spectral response function. （4） HJ-1A CCDs reflectance data exhibited good correlations with grass LAI and fresh biomass, and HJ-1A CCD2 data performed the best.关键词：HJ-1ACCD;TM;reflectance;NDVI;LAI;biomass
- 161
- |
- 711
- |
- 5
发布时间：2021-06-10 - 摘要：As a second generation of China’s polar meteorological satellite, FY-3A and FY-3B were launched in 2008 and 2010, respectively, in sun-synchronous orbits located at the altitude of 831 km. FY-3A and FY-3B load totally 11 sensors, including microwave sensors, including microwave temperature sounder （MWTS）, microwave humidity sounder （MWHS） and microwave radiometer imager （MWRI）. Analysis on technical features of FY-3 MWRI and AMSR-E and intercalibration can be of greatly help for future applications. In this paper, the FY-3 MWRI data over Yangtze River during spring and summer seasons of 2011 were collected because of serious drought, high temperature, precipitation and flooding. Based on radiative transfer and MWRI features, the polarization and scattering indexes for monitoring drought, precipitation and flooding happened are quantitatively analyzed. Results were also compared with both AMSR-E data and ground station records during the same periods.关键词：MWRI;AMSR-E;瞬时视场;辐射校准;极化指数;散射指数
- 156
- |
- 368
- |
- 4
发布时间：2021-06-10 - 摘要：A forest zone extending from west to east of Tianshan Mountain greatly affects the snow mapping accuracy in this area. The ability of the Multi-angle Imaging SpectroRadiometer （MISR） to obtain simultaneous measurements at nine view angles has provided unique information of forest. In this paper, we provided a new method to retrieve snow information in coniferous forest of Tianshan Mountain from MISR data. First, we chose 10 MISR scenes ranging from April 2000 to July 2001, and then ISODATA unsupervised classification was applied to the reflectance image viewed at five different view angles （0°, ±26.1°, ±45.6°） in red band acquired in summer to get the forest-region information. According to the angular signature of two study sites under certain conditions of snow distribution, we found that, when there was snow in the forest, the average of f ive view angles of red band was bigger than 0.1 or the reflectance viewed at 45.6° was 2.5 times more than the reflectance viewed at nadir. Results indicate that directional effects are associated with the snow conditions in the forest, especially in the red band, and the surface anisotropy signature has signif icant potential in retrieving snow information in forest regions.关键词：MISR;multi-angle remote sensing;forest zone of Tianshan Mountain;snow identif ication
- 156
- |
- 653
- |
- 5
发布时间：2021-06-10 - 摘要：By interpreting remote sensing image of Wenchuan earthquake region from Beijing-1 Microsatellite Sensors data, there are a series of NW trending faults which ruptured the belt of Longmen shan faults at a length of 90—110 km, and this phenomenon has been conf irmed partly in f ield. We suggest that Longmen shan faults may show a NS trending faults, the same as Anninghe-Xiaojiang faults before Himalayan orogeny. India began colliding with Eurasia over 50 million years ago, this plate collision makes Tibetan plateau uplift rapidly and elevate the highest mountains in the world and thus attributed the area of the high plateau to eastward-moving along large-scale slip-striking faults, and the mechanically strong lithosphere of the Sichuan Basin obstructs it eastward in Longmen Shan region, thrust and strike slip faulting occur. These faults gradually translate from NNE to NE to NEE from south to north and form the structural pattern which we saw in remote sensing image of Longmen Shan region. If these faults can be validated in the further study in the future, it will provide new ideas to solve many geologic questions, including the reasonable explanations about seismic mechanism of Wenchuan Ms8.0, rupture segmentation of active deformation zones of Longmen Shan fault zones, the transformation of the coseismic displacement that reverse and right-slip components are of comparable magnitude along the southwestern portion of the rupture, but right-slip dominates the northeastern portion of the rupture.关键词：Wenchuan earthquake;NW-faults;remote sensing interpretation;segment of active faults
- 178
- |
- 452
- |
- 2
发布时间：2021-06-10 - 摘要：In order to further improve the practicability of InSAR technology, it is essential to study how to estimate and eliminate the undesired impact of atmospheric effects. In this study, the causes of atmospheric path delay are elaborated and their temporal/spatial distributions in repeat-pass InSAR are analyzed. A new method is proposed to correct the atmospheric effects in high-resolution tandem-mode InSAR through the use of an existing low-resolution DEM. The resultant elevation models obtained with and without the atmospheric correction are compared with the 30m-resolution ASTER GDEM to verify the effectiveness of the proposed method in terms of topographic mapping accuracy.关键词：InSAR;atmospheric effects;phase correction;topographic mapping
- 211
- |
- 627
- |
- 4
发布时间：2021-06-10 - 摘要：The methodology of RFM modeling for spaceborne SAR and its application in SAR image geocoding are investigated in this paper. The issues associated with model construction, parameter solution and ref inement of RFM model are extensively studied. When the rigorous sensor model is known, a virtual control point grid can be established in a terrain-independent way for RFM modeling. A new approach is implemented to obtain unbiased solutions of RFM model parameters at a low computation time cost. The resultant RFM model can be used as a reliable substitute for the Range-Doppler （RD） model for geometric processing of SAR images as the f itting accuracy with reference to the RD model is usually better than 0.01 pixels. However, in general there will be geometric biases in the geocoded SAR images because systematic absolute geolocation errors usually exist in the RD and associated RFM models. To solve this problem, control points are used to derive an additional mathematical transformation to remove the absolute geolocation errors in the RFM model. Experimental results with ENVISAT ASAR data show the effectiveness of the proposed method for RFM model construction.关键词：SAR;Range-Doppler;rational function model;geolocation;geocoding
- 169
- |
- 649
- |
- 1
发布时间：2021-06-10 - 摘要：Envisat Advanced Synthetic Aperture Radar （ASAR） dual-polarization data are shown to be effective for regional forest monitoring. To this scope, an automatic SAR image preprocessing procedure was developed using SRTM DEM and Land-sat TM image for geocoding in rugged terrain and smooth terrain areas, respectively. An object-oriented forest and non-forest classification method was then proposed based on the HH （horizontal transmit and horizontal receive） to HV （horizontal transmit and vertical receive） polarization intensity ratio and HV images ofASAR data at single acquisition time in winter. The developed method was applied to forest and non-forest mapping in Northeast China. The overall accuracy, the user’s accuracy and the producer’s accuracy of forest were 83.7%, 85.6% and 75.7%, respectively. These results indicate that the proposed method is prom- ising for operational forest mapping at regional scale.关键词：EnvisatASAR;forest mapping;object-oriented classification;Northeast China
- 154
- |
- 431
- |
- 3
发布时间：2021-06-10 - 摘要：<正>以"自然与文化遗产空间观测新时代"为主题,第四届国际遥感考古会议将于2012年10月24日—26日在北京召开。本次会议由联合国教科文组织（UNESCO）、中国科学院和国家文物局联合主办,联合国教科文组织国际自然与文化遗产空间技术中心（HIST）与中国科学院对地观测与数字地球科学中心共同承办。会议将重点探讨应用于文化与自然遗产监测与保护、数据记录与存档等领域的前沿空间技术,将为文化与自然遗产管理和保护领域的专家、决策者和学者提供一个权威的国际学术交流平台。
- 50
- |
- 190
- |
- 0
发布时间：2024-10-10 - 摘要：<正>2012年7月21日,美国电子与电气工程师协会（IEEE）地球科学与遥感分会GRSS（Geoscience and Remote Sensing Society）正式批准中国获得2016年国际地球科学与遥感大会IGARSS（International Geoscience And Remote Sensing Symposium）的主办权。IEEE地球科学与遥感分会组织的IGARSS,是全球该领域最具影响力的学术会议,每年轮流在北美、欧洲和亚太地区举办,所有申办国家通过竞争会议主办权获得主办资格。自1997年开始,中国多次组织申办IGARSS,但是由于各种原因均未成功。本次申办活动由复旦大学和中国科学院国家空间科学中心牵头组织,并得到中国科学院对地观测与数字地球科学中心、遥感应用研
- 128
- |
- 94
- |
- 0
发布时间：2021-06-10 - 摘要：<正>资源三号（ZY-3）卫星是中国首颗高精度民用立体测绘卫星,于2012年1月9日11:17在太原卫星发射中心发射升空。ZY-3卫星搭载了一组三线阵立体测绘相机及1台6m分辨率多光谱相机。立体测绘相机由1台2.1m分辨率正视相机和两台3.5m分辨率前、后视相机组成,以"不同视角、联合观测"的方式立体成像。图为中国资源卫星应用中心处理的2012年2月16日迪拜棕榈岛及周边区域影像,由2.1m正视相机影像和6m多光谱相机影像融合而成。
- 110
- |
- 173
- |
- 0
发布时间：2021-06-10
- Postal code：100190
- Tel：010-58887052 Email：nrsb@aircas.ac.cn
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备20021838号-9
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0