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14篇 您的检索式:作者名="Pengfeng Xiao"
    题名 作者 年代 出处 被引量
1Monitoring lake changes of Qinghai-Tibetan Plateau over the past 30 years using satellite remote sensing data显示文摘During the years 2006–2009,lakes in the Qinghai-Tibetan Plateau(QTP)were investigated using satellite remote sensing strategies.We report the results of this investigation as well as follow-up research and expanded work.For the investigation,we mainly focused on lakes whose areas are more than 1 km2.The remote sensing data that we used included 408 scenes of CBERS CCD images and 5 scenes of Landsat ETM?images in Qinghai Province and Tibet Autonomous Region.All these data were acquired around years 2005–2006.Besides remote sensing images,we also collected 1,259 topographic maps.Numbers and areas of lakes were analyzed statistically,which were then compared with those coming from the first lake investigation(implemented between the1960s and 1980s).According to our investigation,up to and around year 2005–2006,the total number of lakes in the QTP was 1,055(222 in Qinghai and 833 in Tibet),accounting for more than 30%of that of China.Thirty newborn lakes with area[1 km2were found,and 5 dead lakes with initial area[1 km2were also found.Among those 13 big lakes([500 km2),Yamzhog Yumco had seriously shrunk,and it has continued to shrink in recent years;Qinghai Lake had shrunk during the period,but some new researches indicated that it has been expanding since the year 2004;Siling Co,Nam Co,and Chibuzhang Co had expanded in the period.We divided the newborn lakes into six categories according to their forming reasons,including river expansion,wetland conversion,etc.The changes of natural conditions led to the death of four lakes,and human exploitation was the main reason for the death of Dalianhai Lake in Qinghai.We picked out three regions which were sensitive to the change of climate and ecological environment:Nagqu Region,Kekexili Region,and the source area of the Yellow River(SAYR).Lakes in both Nagqu and Kekexili have been expanded;meanwhile,most lakes in the SAYR have obviously been shrunk.These regional patterns of lake changes were highly related to variations of temperature,glacier,precipitation,and evaporation.Our investigation and analysis will provide references for researches related to lake changes in the QTP and the response to climate fluctuations.Wei Wan Pengfeng Xiao Xuezhi Feng Hui Li Ronghua Ma Hongtao Duan Limin Zhao 2014Chinese Science Bulletin2014,59,10:22
2Using autologistic spatial models to simulate the distribution of land-use patterns in Zhangjiajie, Hunan Province显示文摘Nowadays,spatial simulation on land use patterns is one of the key contents of LUCC.Modeling is an important tool for simulating land use patterns due to its ability to inte-grate measurements of changes in land cover and the associated drivers.The conventional regression model can only analyze the correlation between land use types and driving factors, but cannot depict the spatial autocorrelation characteristics.Land uses in Yongding County, which is located in the typical karst mountain areas in northwestern Hunan province,were investigated by means of modeling the spatial autocorrelation of land use types with the purpose of deriving better spatial land use patterns on the basis of terrain characteristics and infrastructural conditions.Through incorporating components describing the spatial autocor-relation into a conventional logistic model,we constructed a regression model(Autologistic model),and used this model to simulate and analyze the spatial land use patterns in Yong- ding County.According to the comparison with the conventional logistic model without con- sidering the spatial autocorrelation,this model showed better goodness and higher accuracy of fitting.The distribution of arable land,wood land,built-up land and unused land yielded areas under the ROC curves(AUC)was improved to 0.893,0.940,0.907 and 0.863 respec- tively with the autologistic model.It is argued that the improved model based on autologistic method was reasonable to a certain extent.Meanwhile,these analysis results could provide valuable information for modeling future land use change scenarios with actual conditions of local and regional land use,and the probability maps of land use types obtained from this study could also support government decision-making on land use management for Yongding County and other similar areas.WU Guiping ZENG Yongnian XIAO Pengfeng FENG Xuezhi HU Xiaotian 2010Journal of Geographical Sciences2010,20,2:6
3DNA microarray synthesis by using PDMS molecular stamps (Ⅲ)——Optimization for the reaction conditions显示文摘Optimization for the technological processes of fabricating oligonucleotide microarray by the molecular stamping method is studied in this note. Three factors that affect the pressing coupling reactions of the nucleosides are focused on: the stability of the chemical activities of the reaction solutions, the contamination of the remain of the reactive nucleotides among the different spots on the chip, and the influence of the capping reaction on the hybridization result. The experiments show that the acetonitrile solution of tetrazole and nucleoside monomer could maintain sufficient reactive activity for more than 10 h. An effective method has been used and proved to eliminate the residual reactive nucleosides on chip with small molecules containing hydroxylgroup. Finally, the capping step-a regular step in theconventional DNA chemical synthesis can be neglected in our on-chip DNA synthetic process, which would not affect its hybridization results.XIAO Pengfeng, LU Zuhong, LIU Zhengchun, HE Quanguo & HE NongyueKey Laboratory for Molecular and Biomolecular Electronics of Ministry of Education, Southeast University, Nanjing 210096, China 2002Chinese Science Bulletin2002,47,13:5
4Current signal amplification strategies in aptamer-based electrochemical biosensor:A review显示文摘Due to their high specificity and affinity towards various targets,along with other unique advantages such as stability and low cost,aptamers are widely applied in analytical techniques.A typical aptamerbased electrochemical biosensor is composed of a aptamer as the biological recognition element and transducer converting the biologic interaction into electrical signals for the quantitative measurement of targets.Improvement of the sensitivity of a biosensor is significantly important in order to achieve the detection of biomolecules with low abundance,and different amplification strategies have been explored.The strategies either employ nanomaterials such as gold nanoparticles to con struct electrodes which can transfer the biological reactions more efficiently,or attempt to obtain enhanced signal through multi-labeled carriers or utilize enzyme mimics to catalyze redox cycling.This review discusses recent advances in signal amplification methods and their applications.Critical assessment of each method is also considered.Lei He Rongrong Huang Pengfeng Xiao Yuan Liu Lian Jin Hongna Liu Song Li Yan Deng Zhu Chen Zhiyang Li Nongyue He 2021Chinese Chemical Letters2021,32,5:3
5Uncertainty analysis of cross-calibration for HJ-1 CCD camera显示文摘Radiometric calibration of sensor is the basis of quantitative remote sensing,and uncertainty analysis is critical to ensure the accuracy of cross-calibration.Therefore,firstly,cross-calibration formulas were improved by redefining calibration coefficient and spectral band matching factor.In these formulas,cci was redefined as the calibration coefficient of normalized apparent reflectance,and spectral band matching factor as the ratio of normalized apparent reflectance.Secondly,based on the contrast of ideal and actual conditions in cross-calibration,8 sources of cross-calibration uncertainty were proposed:calibration uncertainty of standard sensor;pixel matching uncertainty;spectral band matching factor uncertainty caused by site altitude setting error,atmospheric parameters setting error,surface spectrum source,surface bidirectional reflectance characteristic,and error of atmospheric radiative transfer model;and uncertainty caused by other factors which were not considered.Finally,the contribution of each uncertainty was further analyzed and discussed for the HJ-1 CCD camera.The results provide many valuable references for evaluating the feasibility of alternative cross-calibration measurements.WANG Zuo XIAO PengFeng GU XingFa FENG XueZhi LI XiaoYing GAO HaiLiang LI Hui LIN JinTang ZHANG XueLiang 2013Chinese Science Bulletin2013,58,7:3
6Determination of trace amount of antimony  by adsorption voltammetry on carbon paste electrode显示文摘Guo Huishi Xiao Pengfeng Nie Libo 2004Journal of Southeast University2004,,:1
7The Solar Upper Transition Region Imager(SUTRI)Onboard the SATech-01 Satellite显示文摘The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of~3 nm.SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm.The on-orbit observations show that SUTRI images have a field of view of~416×416 and a moderate spatial resolution of~8″without an image stabilization system.The normal cadence of SUTRI images is 30 s and the solar observation time is about16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period.Approximately15 GB data is acquired each day and made available online after processing.SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of~0.5 MK in the solar atmosphere,which has rarely been sampled by existing solar imagers.SUTRI observations will establish connections between structures in the lower solar atmosphere and corona,and advance our understanding of various types of solar activity such as flares,filament eruptions,coronal jets and coronal mass ejections.Xianyong Bai Hui Tian Yuanyong Deng Zhanshan Wang Jianfeng Yang Xiaofeng Zhang Yonghe Zhang Runze Qi Nange Wang Yang Gao Jun Yu Chunling He Zhengxiang Shen Lun Shen Song Guo Zhenyong Hou Kaifan Ji Xingzi Bi Wei Duan Xiao Yang Jiaben Lin Ziyao Hu Qian Song Zihao Yang Yajie Chen Weidong Qiao Wei Ge Fu Li Lei Jin Jiawei He Xiaobo Chen Xiaocheng Zhu Junwang He Qi Shi Liu Liu Jinsong Li Dongxiao Xu Rui Liu Taijie Li Zhenggong Feng Yamin Wang Chengcheng Fan Shuo Liu Sifan Guo Zheng Sun Yuchuan Wu Haiyu Li Qi Yang Yuyang Ye Weichen Gu Jiali Wu Zhe Zhang Yue Yu Zeyi Ye Pengfeng Sheng Yifan Wang Wenbin Li Qiushi Huang Zhong Zhang 2023Research in Astronomy and Astrophysics2023,23,6:1
8Seg- mentation of Multispectral Highresolution Satellite Imagery Using Log Gabor Filters显示文摘Xiao Pengfeng Feng Xuezhi An Ru 0,,06:1
9Prepara- tion of hydrophilie poly ( dimethylsiloxane ) stamps by plasma- induced grafting显示文摘He Quanguo Liu Zhengchun Xiao Pengfeng 2003Langrnuir2003,19,17:1
10Boundary - constrained multi - scale segmentation method for remote sensing images 显示文摘Xueliang Zhang Pengfeng Xiao Xiaoqun Song Jiangfeng She 2013ISPRS Journal of Photogrammetry and Remote Sensing2013,15,6:1
11Gel immobilization of acrylamide-modifiedsingle-stranded DNA template for pyrosequencing显示文摘Pengfeng Xiao Huan Huang Guohua Zhou 2007Electrophoresis2007,28,:1
12Boundary-constrained multi-scale segmentation method for remote sensing images显示文摘ZHANG Xueliang XIAO Pengfeng SONG Xiaoqun 2013ISPRS Journal of Photogrammetry and Remote Sensing2013,78,:1
13Image feature detection from phase congruency based on twodimensional Hilbert transform显示文摘Wang Ke Xiao Pengfeng Feng Xuezhi 2011Pattern Recognition Letters2011,32,15:1
14Relationship between Sex Ratio at Age 0 to 4 and Geographical Environment in China显示文摘The Relationship between sex ratio at age 0 to 4 and altitude in China is quantitatively investigated by using Geographical Information System(GIS)technology in this paper.The results show that the counties with high sex ratio at age 0 to 4 in 1990 and 2000 are mainly distributed on the east of the well-known Chinese population division,Anhui-Tengchong line,and there is high negative correlation between sex ratio at age 0 to 4 and altitude in Chinese counties. There are highest sex ratio at age 0 to 4 in the regions under 100 meters,but this ratio over 3200 meters falls into the normal range.And the sex ratio at age 0 to 4 continues to fall down when the altitude rises. So the geographical environment evidently affects the sex ratio at birth.There is higher sex ratio at birth in lower-altitude regions.The effect with altitude may be associated with the ambient tempeture.Kang Guoding Xiao Pengfeng Zhou Changhong 2011China Population Today2011,30,2:0
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