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The Study of Extracting River Nets Based on Intelligence Ant Colony Algorithm on MODIS remote sensing Images

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Journal of Donghua University(English Edition) 2010年第5期27卷 673-680页

作者：时向勇李先华郑成建 Research center of remote sensing and Spatial Information Science Shanghai University

How to extract river nets effectively is of great significance for water resources investigation,flood forecasting and environmental monitoring,*** the paper,combining with ant colony algorithm,a new approach of extracting river nets on moderate-resolution imaging spectroradiometer(MODIS)remote sensing images was proposed through analyzing two general extraction methods of river *** experiment results show that river nets can be optimized by ant colony algorithm efficiently,and difference ratio between the experimental vectorgraph and the data of National Fundamental Geographic Information System is down to 8.7%.The proposed algorithm can work for extracting river nets on MODIS remote sensing images effectively.

关键词： ant colony algorithm river nets MODIS remote sensing images

A method for canopy water content estimation for highly vegetated surfaces-shortwave infrared perpendicular water stress index

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Science China Earth Sciences 2007年第9期50卷 1359-1368页

作者： GHULAM Abduwasit KASIMU Alimujiang Institute of remote sensing and GIS Peking University center for Environmental remote sensing(CEReS) Chiba University33 Yayoi-cho Inage-ku Chiba 263-8522Japan

In this paper, a new method for canopy water content (FMC) estimation for highly vegetated surfaces- shortwave infrared perpendicular water stress index (SPSI) is developed using NIR, SWIR wavelengths of Enhanced Thematic Mapper Plus (ETM+) on the basis of spectral features and distribution of surface targets with different water conditions in NIR-SWIR spectral space. The developed method is further explored with radiative transfer simulations using PROSPECT, Lillesaeter, SailH and 6S. It is evident from the results of validation derived from satellite synchronous field measurements that SPSI is highly correlated with FMC, coefficient of determination (R squared) and root mean square error are 0.79 and 26.41%. The paper concludes that SPSI has a potential in vegetation water content estimation in terms of FMC.

关键词： leaf water content, shortwave infrared perpendicular water stress index (SPSI), remote estimation of vegetation water content

Vulnerability and Resilience Research:A Critical Perspective

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International Journal of Disaster Risk Science 2014年第1期5卷 86-87页

作者： Hannes Taubenbock Christian Geiв German remote sensing Data center German Aerospace CenterOberpfaffenhofen82234 WesslingGermany

‘‘Vulnerability’’and‘‘resilience’’are terms of such broad conceptual meaning as to be almost useless for careful scientific communication,except as rhetorical indicators of areas of greatest *** is a reflection of the complexity of their meaning,an uncoordinated search among different fields for a common understanding,and maybe the difficulty of systematizing these complicated issues among the various involved parties.

关键词： Resilience difficulty coordinated

Study on thermal infrared emission directionality over crop canopies with TIR camera imagery

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Science China(Technological Sciences) 2000年第S1期43卷 95-103,113页

作者：柳钦火顾行法李小文田国良余涛 F.Jacob J.F.Hanocq M.Friedl A.H.Strahler Laboratory of remote sensing Information Sciences Chinese Academy of Sciences Beijing China center for remote sensing Boston University Boston USA INRA-Unite De Bioclimatoligie Avignon France center for remote sensing and GIS Beijing Normal University Beijing China

In order to investigate directionality of thermal infrared emission from crop canopies, a wide-angle thermal video camera (INFRAMETRICS) equipped with an 80?FOV lens was mounted on a small aircraft and used to acquire thermal imagery along several different flight traces. Accordingly, multi-angle directional brightness temperatures were acquired at different view angles for individual pixel. The flight experiment was carried out from January 1997 to October 1997 over a 5 kmx5 km flat agricultural area, located near Avignon, southeastern *** paper presents results from analyses performed using these data including instrument calibration, radiometric correction, atmospheric correction, temperature temporal adjustment, geometric matching and registration of images. Results are presented for different thermal infrared emission patterns of different surface types including bare soil, wheat, maize and sunflower at different growth stages.

关键词： TIR emission directionality airborne experiment crop canopy

Information flow and controlling in regularization inversion of quantitative remote sensing

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Science China Earth Sciences 2005年第1期48卷 74-83页

作者： YANG Hua, XU Wangli, ZHAO Hongrui, CHEN Xue & WANG Jindi Research center for remote sensing and GIS, School of Geography, Beijing Normal University, State Key Laboratory of remote sensing Science, Beijing Key Laboratory for remote sensing of Environment and Digital Cities, Beijing 100875, China Department of Mathematics, Beijing Normal University, Beijing 100875, China Research center for remote sensing and GIS School of Geography Beijing Normal University State Key Laboratory of Remote Sensing Science Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of Mathematics Beijing Normal University Beijing China

In order to minimize uncertainty of the inversed parameters to the largest extent by making full use of the limited information in remote sensing data, it is necessary to understand what the information flow in quantitative remote sensing model inversion is, thus control the information flow. Aiming at this, the paper takes the linear kernel-driven model inversion as an example. At first, the information flow in different inversion methods is calculated and analyzed, then the effect of information flow controlled by multi-stage inversion strategy is studied, finally, an information matrix based on USM is defined to control information flow in inversion. It shows that using Shannon entropy decrease of the inversed parameters can express information flow more properly. Changing the weight of a priori knowledge in inversion or fixing parameters and partitioning datasets in multi-stage inversion strategy can control information flow. In regularization inversion of remote sensing, information matrix based on USM may be a better tool for quantitatively controlling information flow.

关键词： regularization inversion, information flow, Shannon entropy decrease, information matrix.

Using UAVs for detection of trees from digital surface models

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Journal of Forestry Research 2018年第3期29卷 804-812页

作者： Nusret Demir Department of Space Science and Technologies Remote Sensing Research and Application Center Akdeniz University

A difficult problem in forestry is tree *** this study, a GoProHero attached to a small unmanned aerial vehicle was used to capture images of a small area covered by pinus pinea trees. Then, a digital surface model was generated with image matching. The elevation model representing the terrain surface, a ‘digital terrain model’,was extracted from the digital surface model using morphological filtering. Individual trees were extracted by analyzing elevation flow on the digital elevation model because the elevation reached the highest value on the tree peaks compared to the neighborhood elevation pixels. The quality of the results was assessed by comparison with reference data for correctness of the estimated number of trees. The tree heights were calculated and evaluated with ground truth dataset. The results showed 80% correctness and 90% completeness.

关键词： Tree detection Digital surface model Fish-eye camera Photogrammetry UAV

Polarimetric scattering and transmitting of the Stokes vector from a layer of chiral small spheroids

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Science in China(Series F) 2002年第2期45卷 130-142页

作者：常梅金亚秋 center for Wave Scattering and remote sensing Fudan University Shanghai China

To measure fully polarimetric scattering from random chiral small spheroids, the 2×2 dimensional (2×2-D) complex scattering amplitude matrix of randomly oriented, chiral small spheroid is derived. Polarimetric scattering from a bounded layer of non-uniformly oriented, chirally-active small spheroids in the Mueller matrix solution is obtained. Co-polarized and cross-polarized backscattering and polarization degree for any polarized incidence (χ, ψ) are numerically calculated. Transmitting of coherent Stokes parameters through the layer are also discussed. Either non-uniform orientation or chi-rality can yield non-diagonal extinction matrix ke and full eigenmatrix E due to the fact of forward depolarized-scattering functions , ≠ 0. Comparisons of fully polarimetric scattering from the chiral and achiral particulate media demonstrate the chirality effect on wave scattering and transmitting.

关键词： chirality non-spherical particle scattering and transmitting.

Estimation of Organic Matter Content in Coastal Soil Using Reflectance Spectroscopy

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Pedosphere 2016年第1期26卷 130-136页

作者： ZHENG Guanghui Dongryeol RYU JIAO Caixia HONG Changqiao School of Geography and remote sensing Nanjing University of Information Science & Technology Department of Infrastructure Engineering University of Melbourne

Rapid determination of soil organic matter(SOM) using regression models based on soil reflectance spectral data serves an important function in precision agriculture. "Deviation of arch"(DOA)-based regression and partial least squares regression(PLSR)are two modeling approaches to predict ***,few studies have explored the accuracy of the DOA-based regression and PLSR ***,the DOA-based regression and PLSR were applied to the visible near-infrared(VNIR) spectra to estimate SOM content in the case of various dataset divisions.A two-fold cross-validation scheme was adopted and repeated 10 000 times for rigorous evaluation of the DOA-based models in comparison with the widely used PLSR *** samples were collected for SOM analysis in the coastal area of northern Jiangsu Province,*** results indicated that both modelling methods provided reasonable estimation of SOM,with PLSR outperforming DOA-based regression in ***,the performance of PLSR for the validation dataset decreased more *** the four DOA-based regression models,a linear model provided the best estimation of SOM and a cutoff of SOM content(19.76 g kg^(-1)),and the performance for calibration and validation datasets was *** the SOM content exceeded 19.76 g kg^(-1),SOM became more effective in masking the spectral features of other soil properties to a certain *** work confirmed that reflectance spectroscopy combined with PLSR could serve as a non-destructive and cost-efficient way for rapid determination of SOM when hyperspectral data were *** DOA-based model,which requires only 3 bands in the visible spectra,also provided SOM estimation with acceptable accuracy.

关键词： deviation of arch multiple regression partial least squares regression reflectance spectra soil organic matter

Studying Air Pollution with Kitt Peak Solar Flux Atlas—Analysis Method and Results of Observation

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Advances in Atmospheric Sciences 2000年第3期17卷 363-374页

作者： Jianguo Niu Hiroaki Kuze and Nobuo Takeuchi(center for Environmental remote sensing, Chiba University, Chiba-shi Inage-ku, 263-8522, Japan)(E-mail : niujian＠ceres. cr. chiba-u. ac.jp)(http.//arbs8. larc, nasa,gov/sage3/objectives/dataprods.html) center for Environmental remote sensing Chiba University Chiba- shi Inage- ku Japan

For the measurement of atmospheric NO2 vertical column density (VCD), Kitt Peak Solar Flux Atlas can be substituted as an extraterrestrial solar radiation. Compared with differential analysis method, the Taylor expansion of integrated transfer equation underestimates the VCD. This underestimation is as large as 35% when the amount of NO2 is 1 × 1017 cm?2 and observation is conducted with an air mass factor of 10. Even when the VCD is 2 × 1016 cm?2 and the air mass factor is 4, the relative error of the retrieved VCD is still no less than 3%. If the observation is restricted under the small air mass factor condition (≤ 4), with Kitt Peak Solar spectrum as an extraterrestrial solar radiation, only an atmospheric layer of 2 km thick from ground can be studied, which will make the absorption too weak to be detected by normal instruments. The VCD in winter Tokyo area was observed and analyzed by differential method, which shows a good precision even when the absorption is as low as 3%. The largest average VCD was about 1.3 × 1017 cm-2, and the lowest was about 1.3 × 1016 cm?2. The trend of its variation was almost the same as the ground level observation by Saltzman reagent method. Key words Vertical column density (VCD) - Extraterrestrial solar radiation - NO2 - Atmospheric contamination

关键词： Vertical column density (VCD) Extraterrestrial solar radiation NO2 Atmospheric contamination