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A Machine Learning-Based Geostatistical Downscaling Method for Coarse-Resolution Soil Moisture Products 期刊论文  OAI收割
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING, 2021, 卷号: 14, 页码: 1025-1037
作者:  Jin, Yan;  Ge, Yong;  Liu, Yaojie;  Chen, Yuehong;  Zhang, Haitao
  |  收藏  |  浏览/下载：39/0  |  提交时间：2021/03/15
A Machine Learning-Based Geostatistical Downscaling Method for Coarse-Resolution Soil Moisture Products 期刊论文  OAI收割
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING, 2021, 卷号: 14, 页码: 1025-1037
作者:  Jin, Yan;  Ge, Yong;  Liu, Yaojie;  Chen, Yuehong;  Zhang, Haitao
  |  收藏  |  浏览/下载：23/0  |  提交时间：2021/03/15
黄海桑沟湾水体及沉积物中微塑料污染特征研究 期刊论文  OAI收割
海洋环境科学, 2019, 卷号: 38, 期号: 2, 页码: 198-204
作者:  熊宽旭;  赵新月;  周倩;  付传城;  涂晨
  |  收藏  |  浏览/下载：47/0  |  提交时间：2020/06/17
桑沟湾  微塑料  潮滩  丰度  空间分布  Sanggou bay  microplastics  tidal flats  abundance  spatial distribution  In recent years,research on microplastics pollution in the marine environment has been increasing,but studies on microplastics in water bodies and sediments of the bay under the influence of high-intensity human activities are still rarely reported. In this study,the pollution characteristics of microplastics in the wayer and sediments of Sanggou bay were investigated in December 2017,after the harvest of large-scale aquaculture,with the aim to study the effects of aquaculture activities and hydrodynamics on pollution characteristics and spatial distribution of microplastics in the bay. The results showed that the types of microplastics in the water and sediments of Sanggou bay were mainly fibers,fragments,films,foams and particles. The microplastic abundances in the water and sediments were 1.8 ~ 31.2 N/L,31.2 ~ 1246.8 N/kg,respectively. The average particle sizes of microplastics in water and sediments were 0.51 0.20 mm and 1.54 1.02 mm,respectively. The results of spatial distribution of microplastics in Sanggou bay showed that the high abundance area mainly appears in the inshore waters,and the abundance of microplastics tends to decrease from the inner areas of estuary to the outshore areas. The heterogeneity of microplastic abundance and spatial distribution in Sanggou bay is mainly affected by human activities such as aquaculture,living and shipping,as well as hydrodynamics. In the future,fine sampling and analysis are needed to fully understand the temporal and spatial distribution of microplastics pollution in the bay areas.  
Evaluating Spatial Representativeness of Station Observations for Remotely Sensed Leaf Area Index Products 期刊论文  OAI收割
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING, 2016, 卷号: 9, 期号: 7, 页码: 3267-3282
作者:  Xu, Baodong;  Li, Jing;  Liu, Qinhuo;  Huete, Alfredo R.;  Yu, Qiang
收藏  |  浏览/下载：47/0  |  提交时间：2016/12/19
可持续发展实验区绿地系统可达性比较研究 学位论文  OAI收割
硕士, 北京: 中国科学院研究生院, 2016
作者:  张娜娜
收藏  |  浏览/下载：33/0  |  提交时间：2017/08/07
Evaluation of spatial upscaling methods based on remote sensing data with multiple spatial resolutions (EI CONFERENCE) 会议论文  OAI收割
Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states
Ren R.; Gu L.; Cao J.; Chen H.; Sun J.
收藏  |  浏览/下载：36/0  |  提交时间：2013/03/25
In most applications of remote sensing data  special spatial information is required from a finer to a coarser spatial resolution with appropriate upscaling methods. The purpose of this paper is to compare and evaluate current spatial upscaling methods using MODIS remote sensing data with multiple spatial resolutions. In the research  Northeast China was selected as the study area. MODIS data with spatial resolutions of 250 m (2 bands) and 500 m (7 bands) were used as the test data. Through using the selected upscaling methods  the Band 1 and Band 2 data of MODIS were scaled up from 250 m to 500 m spatial resolution. On the basis of land cover characteristics of Northeast China  the MODIS data located in the study area was classified into the five land cover types  including water  grasslands  forests  farmlands and bare lands using maximum likelihood method. The land cover classification results were further compared with MODIS Land Cover Type product. Finally  Structural Similarity (SSIM) was selected to evaluate the effects of these upscaling methods. The research can provide more useful information for spatial scaling transformation in remote sensing data applications. 2012 SPIE.  
Research on infrared dim-point target detection and tracking under sea-sky-line complex background (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  Dong Y.-X.;  Zhang H.-B.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载：117/0  |  提交时间：2013/03/25
Target detection and tracking technology in infrared image is an important part of modern military defense system. Infrared dim-point targets detection and recognition under complex background is a difficulty and important strategic value and challenging research topic. The main objects that carrier-borne infrared vigilance system detected are sea-skimming aircrafts and missiles. Due to the characteristics of wide field of view of vigilance system  the target is usually under the sea clutter. Detection and recognition of the target will be taken great difficulties.There are some traditional point target detection algorithms  such as adaptive background prediction detecting method. When background has dispersion-decreasing structure  the traditional target detection algorithms would be more useful. But when the background has large gray gradient  such as sea-sky-line  sea waves etc.The bigger false-alarm rate will be taken in these local area.It could not obtain satisfactory results. Because dim-point target itself does not have obvious geometry or texture feature  in our opinion  from the perspective of mathematics  the detection of dim-point targets in image is about singular function analysis.And from the perspective image processing analysis  the judgment of isolated singularity in the image is key problem. The foregoing points for dim-point targets detection  its essence is a separation of target and background of different singularity characteristics.The image from infrared sensor usually accompanied by different kinds of noise. These external noises could be caused by the complicated background or from the sensor itself. The noise might affect target detection and tracking. Therefore  the purpose of the image preprocessing is to reduce the effects from noise  also to raise the SNR of image  and to increase the contrast of target and background. According to the low sea-skimming infrared flying small target characteristics  the median filter is used to eliminate noise  improve signal-to-noise ratio  then the multi-point multi-storey vertical Sobel algorithm will be used to detect the sea-sky-line  so that we can segment sea and sky in the image. Finally using centroid tracking method to capture and trace target. This method has been successfully used to trace target under the sea-sky complex background. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
中国典型地区人文—经济地理研究进展与展望[J] 期刊论文  OAI收割
地理科学进展, 2011, 卷号: 12, 页码: 1538-1547
作者:  陈雯;  张平宇;  张小雷;  邓伟;  杨兆萍
  |  收藏  |  浏览/下载：25/0  |  提交时间：2017/12/29
Numerical Study on the Spatial and Temporal Characteristics of Water Quality in the Taihu Lake of China 会议论文  OAI收割
Hydrology Conference 2010 (The Changing Physical and Social Environment: Hydrologic Impacts and Feedbacks), San Diego, CA, USA, 2010-10-11~ 2010-10-13
作者:  Liu QQ(刘青泉)
收藏  |  浏览/下载：34/0  |  提交时间：2010/12/27
A study on atmospheric turbulence effects in full-optical free-space communication systems (EI CONFERENCE) 会议论文  OAI收割
2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China
作者:  Liu P.
收藏  |  浏览/下载：32/0  |  提交时间：2013/03/25
Next generation free-space optical communication systems have used fiber-optic technology as the seamless connection between free-space and optical fiber. The full-optical free-space optical communication systems use optical fiber as the receiver to get faster communication speed. The atmospheric turbulence deeply influenced on the optical wave propagated in terrestrial application. As the active receiving area of the full-optical free-space optical communication systems is very small  it is important to research on the atmospheric turbulence effects on the full-optical free-space optical communication system. In this paper  we discuss about both the turbulence-induced intensity fluctuations and the angle-of-arrival effects in full-optical free-space optical communication systems which are used in a few kilometers communication. We gave the numerical results of the atmosphere turbulence effects on the free-space optical communication systems. In order to minimize the atmospheric turbulence influence on the full-optical free-space optical communications system  we also investigate the use of fine tracking system in the communication system. We have set up a full-optical free-space communication system in Tokyo and received useful data from the experiment. We compared the receiving power of the experiment  when the fine tracking system is On and Off. From the experiment results  we can see that the fine tracking system effectively mitigates the atmospheric turbulence and increases the receiving power of the communication system. 2010 IEEE.