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International Journal of Digital Earth 2011年第3期4卷 258-270页

作者： R.V.Sheeja Sabu Joseph D.S.Jaya R.S.Baiju kerala state remote sensing and environment centre VikasbhavanThiruvananthapuram 695033KeralaIndia Department of environmental Sciences University of KeralaKariyavattomThiruvananthapuramKeralaIndia centre for Earth Science Studies(CESS) ThiruvananthapuramKeralaIndia

Land use and land cover change,perhaps the most significant anthropogenic disturbance to the environment,mainly due to rapid urbanization/industrialization and large scale agricultural *** this paper,an attempt has been made to appraise land use/land cover changes over a century(19142007)in the Neyyar River Basin(L56 km;Area483.4 km2)in southern keralaa biodiversity hot spot in Peninsular *** this study,digital remote sensing data of the Indian remote sensing satellite series I-D(LISS III,20062007)on 1:50,000 scale,Survey of India(SOI)toposheet of 1914(1:63,360)and 1967(1:50,000)have been utilized to map various land use/land cover *** of different periods have been registered and resampled to similar geographic coordinates using ERDAS Imagine *** most notable changes include decreases in areas of paddy cultivation,mixed crops,scrub lands and evergreen forests,and increases in built-up areas,rubber plantations,dense mixed forests,and water ***,large scale exploitation of flood plain mud and river sand have reached menacing proportions leading to bank caving and cut offs at channel *** of land and water resources forms an important aspect of ecosystem management in the basin.

关键词： remote sensing GIS land use/land cover Neyyar basin kerala

Quantification of occlusions influencing the tree stem curve retrieving from single-scan terrestrial laser scanning data

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Forest Ecosystems 2019年第4期6卷 285-297页

作者： Peng Wan Tiejun Wang Wuming Zhang Xinlian Liang Andrew K.Skidmore Guangjian Yan state Key Laboratory of remote sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences Beijing Engineering Research Centre for Global Land Remote Sensing Products Institute of Remote Sensing Science and Engineering Faculty of Geographical Science Beijing Normal University

Background: The stem curve of standing trees is an essential parameter for accurate estimation of stem *** study aims to directly quantify the occlusions within the single-scan terrestrial laser scanning(TLS) data,evaluate its correlation with the accuracy of the retrieved stem curves, and subsequently, to assess the capacity of single-scan TLS to estimate stem ***: We proposed an index, occlusion rate, to quantify the occlusion level in TLS data. We then analyzed three influencing factors for the occlusion rate: the percentage of basal area near the scanning center, the scanning distance and the source of occlusions. Finally, we evaluated the effects of occlusions on stem curve estimates from single-scan TLS ***: The results showed that the correlations between the occlusion rate and the stem curve estimation accuracies were strong(r = 0.60–0.83), so was the correlations between the occlusion rate and its influencing factors(r = 0.84–0.99). It also showed that the occlusions from tree stems were the main factor of the low detection rate of stems, while the non-stem components mainly influenced the completeness of the retrieved stem ***: Our study demonstrates that the occlusions significantly affect the accuracy of stem curve retrieval from the single-scan TLS data in a typical-size(32 m × 32 m) forest plot. However, the single-scan mode has the capacity to accurately estimate the stem curve in a small forest plot(< 10 m × 10 m) or a plot with a lower occlusion rate, such as less than 35% in our tested datasets. The findings from this study are useful for guiding the practice of retrieving forest parameters using single-scan TLS data.

关键词： Stem curve Stem volume Terrestrial laser scanning Scan mode

Improved Cubemap model for 3D navigation in geo-virtual reality

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International Journal of Digital Earth 2015年第11期8卷 877-900页

作者： Qishen Duan Jianhua Gong Wenhang Li Shen Shen Rong Li state Key Laboratory of remote sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingChina Zhejiang&CAS Application centre for Geoinformatics ZhejiangChina

Due to advances in rendering techniques and hardware capability,stereoscopic 3D(s3D)visualization is becoming increasingly common in daily ***,this does not change the fact that stereo effects and visual comfort depend greatly on how the related parameters are controlled during the production of the s3D *** geovirtual reality systems,which are important browsers for Digital Earth,the maintenance of these parameters is deeply related to the navigation ***,the navigation method in such systems requires special *** paper presents a new flying method based on a Cubemap *** method defines a Vehicle model and modifies the original Cubemap structure by adding a front view camera during the navigation;it allows the users to fly through a virtual geographic environment with automatic speed control,smooth collision resolution,and dynamic adjustment of the s3D-related parameters.A user test was conducted to compare this new method with the original method based on the Cubemap *** results show that the new method performs better than the former one for it provides a convenient interaction experience with improved stereoscopic effect,and diminishes visual discomfort.

关键词： virtual reality navigation Digital Earth virtual geographic environment

Bamboo resources of Sikkim Himalaya: diversity, distribution and utilization

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Journal of Forestry Research 2014年第4期25卷 929-934页

作者： Deo Kumar Tamang Dinesh Dhakal D. G. Shrestha Sikkim state remote sensing Application centre Sikkim State Council of Science and Technology Development Area Gangtok 737101 Sikkim

We recorded 8 genera and over 30 species of bamboo in Sikkim of the reported 23 genera and 125 species in Indi＆ Thirty percent of bamboo species were recorded in tropical forests （0-900 m）, 40% of species in sub-tropical forests （900-1,800 m）, 17% of species in temper- ate forests （1,800-2,700 m）, 9% of species in sub-alpine forests （2,700-3,500 m） and 4% of species in alpine vegetation （3,500-4,500 m）. Bamboo is used for various purposes and its versatility qualifies it to be a multiple-use alternative to timber, food for villagers and for tribal in particular. Bamboo is also equally important to Red Panda （Ailurusful- gens）, the state animal of Sikkim. We develop a list of bamboos occur- ring in Sikkim with their vernacular names, distributions and uses in the Himalayan state. However, more extensive study is required to fully describe the bamboo diversity of the Himalayan state.

关键词： bamboo Dendrocalamus diversity uses Sikkim

Eurasian Winter Cooling: Intercomparison of Reanalyses and CMIP5 Data Sets

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Atmospheric and Oceanic Science Letters 2013年第5期6卷 324-331页

作者： Stephen OUTTEN Richard DAVY Igor ESAU Nansen environmental and remote sensing centre

A cooling trend in wintertime surface air temperature over continental Eurasia has been identified in reanalysis and the Coupled Model Inter-comparison Project phase 5(CMIP5)‘historical’simulations over the period 1989–*** the authors have shown that this cooling trend is related to changes in Arctic sea-ice around the Barents-Kara *** study illustrates a consistent spatial and temporal structure of the wintertime temperature variability centered over Asia using state-of-the-art reanalyses and global climate model *** findings indicate that there is a physical basis for seasonal predictions of near-surface temperatures over continental Asia based on changes to the ice-cover in the Barents-Kara seas.

关键词： climate change climate simulation atmospheric tele-connections

Land cover classification from remote sensing images based on multi-scale fully convolutional network

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Geo-Spatial Information Science 2022年第2期25卷 278-294页

作者： Rui Li Shunyi Zheng Chenxi Duan Libo Wang Ce Zhang School of remote sensing and Information Engineering Wuhan UniversityWuhanChina Faculty of Geo-Information Science and Earth Observation(ITC) University of TwenteEnschedeThe Netherlands The state Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Lancaster environment centre Lancaster UniversityLancasterUK UK centre for Ecology&Hydrology LancasterUK

Although the Convolutional Neural Network(CNN)has shown great potential for land cover classification,the frequently used single-scale convolution kernel limits the scope of informa-tion ***,we propose a Multi-Scale Fully Convolutional Network(MSFCN)with a multi-scale convolutional kernel as well as a Channel Attention Block(CAB)and a Global Pooling Module(GPM)in this paper to exploit discriminative representations from two-dimensional(2D)satellite ***,to explore the ability of the proposed MSFCN for spatio-temporal images,we expand our MSFCN to three-dimension using three-dimensional(3D)CNN,capable of harnessing each land cover category’s time series interac-tion from the reshaped spatio-temporal remote sensing *** verify the effectiveness of the proposed MSFCN,we conduct experiments on two spatial datasets and two spatio-temporal *** proposed MSFCN achieves 60.366%on the WHDLD dataset and 75.127%on the GID dataset in terms of mIoU index while the figures for two spatio-temporal datasets are 87.753%and 77.156%.Extensive comparative experiments and abla-tion studies demonstrate the effectiveness of the proposed MSFCN.

关键词： Spatio-temporal remote sensing images Multi-Scale Fully Convolutional Network land cover classification

A stream-based Parasitic Model for implementing Mobile Digital Earth

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International Journal of Digital Earth 2014年第1期7卷 38-52页

作者： Wenhang Li Jianhua Gong Ping Yu Qishen Duan Yuling Zou state Key Laboratory of remote sensing Science Institute of Remote Sensing ApplicationsChinese Academy of SciencesBeijingChina Zhejiang&CAS Application centre for Geoinformatics ZhejiangChina School of Management Xinxiang UniversityHenanChina

A Parasitic Model is proposed in this study for Digital Earth running on mobile phones through a mobile *** of mobile phones’limited capabilities in high-performance computing,rendering,storing,and networking(CRSN),these functions are accomplished by a superior host computer in this *** virtual scenes are compressed in a time-series as a data stream and are sent to the mobile phone through a mobile network,thus allowing Digital Earth to be operated on a mobile *** study examines a prototype and shows that a Mobile Digital Earth based on a Parasitic Model can achieve functionality beyond the mobile phone’s actual hardware capabilities and can reduce network *** results demonstrate quasi-real-time interactions,but with bandwidth increases in next-generation mobile networks such as 4G and 5G,there is potential for real-time interactions in the near future.

关键词： Parasitic Model Mobile Digital Earth adaptive transfer strategy mobile phone mobile network

L curve for spherical triangle region quadtrees

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Science China(Technological Sciences) 2004年第3期47卷 265-280页

作者： YUAN Wen1,CHENG Chengqi1,MA Ainai1 & GUAN Xiaojing2 1.Institute of remote sensing and Geography Information System,Peking University,Beijing 100871,China 2.centre of state Information,Beijing 100045,China Institute of remote sensing and Geography Information System Peking University Beijing 100871 China centre of state Information Beijing 100045 China

The sequence of facets and nodes has a direct influence on the efficiency of access to spherical triangle region quadtree. Based on the labeling schema by Lee, spatial curves both for facets and nodes are proposed and the main algorithms for coordinate translation, node Lsequence generation and visiting nodes are presented. In particular,constant time algorithms for generating node Lsequence are advanced by using bit manipulation operations,which can be easily implemented with hardware. In L curve the distance between three nodes of a facet is mostly limited in a range of small value, thus making fast access possible. Though codes of sibling facets are continuous, the difference between codes of some cousins may occasionally be very large and makes the distance of a few facets also very large, thus greatly increasing the mean node distance and the total traversing distance. Therefore an m cluster of nodes is proposed as a basic storage unit fo n cluster, which should store eery shared node in each,and the distance between three nodes of a facet is limited to a controllagle scope.

关键词： global grid, spherical triangle region quadtree, SQT, QTM, space-filling curve.

A Synergic Algorithm for Retrieval of Aerosol Optical Depth over Land

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Advances in Atmospheric Sciences 2009年第5期26卷 973-983页

作者：郭建平薛勇曹春香张颢光洁张小曳李小文 centre for Atmosphere Watch and Services Chinese Academy of Meteorological Sciences China Meteorological Administration state Key Laboratory of remote sensing Sciences Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Institute of Remote Sensing Applications Chinese Academy of Sciences Department of Computing London Metropolitan University Graduate University Chinese Academy of Sciences

In this paper, a novel algorithm for aerosol optical depth（AOD） retrieval with a 1 km spatial resolution over land is presented using the Advanced Along Track Scanning Radiometer （AATSR） dual-view capability at 0.55, 0.66 and 0.87μm, in combination with the Bi-directional Reflectance Distribution Function （BRDF） model, a product of the Moderate Resolution Imaging Spectroradiometer （MODIS）. The BRDF characteristics of the land surface, i.e. prior input parameters for this algorithm, are computed by extracting the geometrical information from AATSR and reducing the kernels from the MODIS BRDF/Albedo Model Parameters Product. Finally, AOD, with a i km resolution at 0.55, 0.66 and 0.87 μm for the forward and nadir views of AATSR, can be simultaneously obtained. Extensive validations of AOD derived from AATSR during the period from August 2005 to July 2006 in Beijing and its surrounding area, against in-situ AErosol RObotic NETwork （AERONET） measurements, were performed. The AOD difference between the retrievals from the forward and nadir views of AATSR was less than 5.72%, 1.9% and 13.7%, respectively. Meanwhile, it was found that the AATSR retrievals using the synergic algorithm developed in this paper are more favorable than those by assuming a Lambert surface, for the coefficient of determination between AATSR derived AOD and AERONET mearured AOD, decreased by 15.5% and 18.5%, compared to those derived by the synergic algorithm. This further suggests that the synergic algorithm can be potentially used in climate change and air quality monitoring.

关键词： Advanced Along Track Scanning Radiometer AOD Bi-directional Reflectance Distribution Function AERONET

Chloroplast gene matK holds the barcodes for identification of Momordica(Cucurbitaceae) species from Indian subcontinent

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Horticultural Plant Journal 2022年第1期8卷 89-98页

作者： Girme Aoudumbar Ramesh Deepu Mathew K.Joseph John V.Ravisankarc centre for Plant Biotechnology and Molecular Biology Kerala Agricultural UniversityThrissurKerala State 680656India ICAR-National Bureau of Plant Genetic Resources Regional StationThrissurKerala State 680656India Bioinformatics centre Kerala Agricultural UniversityThrissurKerala State680656India

DNA barcoding is a supplementary tool in plant systematics,extensively used to resolve the species level *** paper details the identification of DNA barcodes for seven species of Momordica,using the chloroplast gene mat *** the species *** has been confused as a member of the genus Luffa,26 accessions of Momordica belonging to seven Indian species and two accessions of Luffa acutangula were included in this *** of mat K sequences has yielded distinct barcodes in *** ***,*** ***,***,***,*** and also in Luffa *** status of each species was reflected as nucleotide polymorphisms in each *** wild species *** and *** have yielded one barcode but failed to get ***,this study provides conclusive proof that *** is a member of Momordica *** phylogram generated was successful to distinguish the monoecious species of this genus,***,*** and ***,from the dioecious species ***,***,*** *** and ***,mat K locus,by accumulating the evolutionary sequence variations,is proven efficient to differentiate the Momordica species and to reveal their relatedness.

关键词： Cucurbit DNA barcoding Luffa Phylogeny systematics