检索结果-南通市图书馆

Early-season crop type mapping using 30-m reference time series

Journal of Integrative Agriculture 2020年第7期19卷 1897-1911页

作者： HAO Peng-yu TANG Hua-jun CHEN Zhong-xin MENG Qing-yan KANG Yu-peng key laboratory of Agricultural Remote Sensing Minstry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agrcultural SciencesBejing 100081P.R China Shenzhen key laboratory for geo-environmental monitoring of coastal zone of the national administration of surveying Mapping and Geo-Information&Shenzhen Key Laboratory of Spatial Smart Sensing and ServicesShenzhen UniversityShenzhen 518060P.R.China Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBejjing 100101P.R.China

Early-season crop type mapping could provide important information for crop growth monitoring and yield prediction,but the lack of ground-surveyed training samples is the main challenge for crop type *** reference time series based method(RBM)has been proposed to identify crop types without the use of ground-surveyed training samples,the methods are not suitable for study regions with small field size because the reference time series are mainly generated using data set with low spatial *** the combination of Landsat data and Sentinel-2 data could increase the temporal resolution of 30-m image time series,we improved the RBM by generating reference normalized difference vegetation index(NDVI)/enhanced vegetation index(EVI)time series at 30-m resolution(30-m RBM)using both Landsat and Sentinel-2 data,then tried to estimate the potential of the reference NDVI/EVI time series for crop identification at early *** a test case,we tried to use the 30-m RBM to identify major crop types in Hengshui,China at early season of 2018,the results showed that when the time series of the entire growing season were used for classification,overall classification accuracies of the 30-m RBM were higher than 95%,which were similar to the accuracies acquired using the ground-surveyed training *** addition,cotton,spring maize and summer maize distribution could be accurately generated 8,6 and 8 weeks before their harvest using the 30-m RBM;but winter wheat can only be accurately identified around the harvest time ***,NDVI outperformed EVI for crop type classification as NDVI had better separability for distinguishing crops at the green-up time *** with the previous RBM,advantage of 30-m RBM is that the method could use the samples of the small fields to generate reference time series and process image time series with missing value for early-season crop casification;while,samples collected from multiple years should be futher

关键词： early season Landsat Sentinel-2 reference time series crop classification Hengshui

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

High resolution crop intensity mapping using harmonized Landsat-8 and Sentinel-2 data

引用

Journal of Integrative Agriculture 2019年第12期18卷 2883-2897页

作者： HAO Peng-yu TANG Hua-jun CHEN Zhong-xin YU Le WU Ming-quan key laboratory of Agricultural Remote Sensing Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China key laboratory for geo-environmental monitoring of coastal zone of the national administration of surveying Mapping and Geo Information/Shenzhen Key Laboratory of Spatial Smart Sensing and ServicesShenzhen UniversityShenzhen 518060P.R.China Ministry of Education key laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084P.R.China State key laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101P.R.China

An increase in crop intensity could improve crop yield but may also lead to a series of environmental problems, such as depletion of ground water and increased soil salinity. The generation of high resolution(30 m) crop intensity maps is an important method used to monitor these changes, but this is challenging because the temporal resolution of the 30-m image time series is low due to the long satellite revisit period and high cloud coverage. The recently launched Sentinel-2 satellite could provide optical images at 10–60 m resolution and thus improve the temporal resolution of the 30-m image time series. This study used harmonized Landsat Sentinel-2(HLS) data to identify crop intensity. The sixth polynomial function was used to fit the normalized difference vegetation index(NDVI) and enhanced vegetation index(EVI) curves. Then, 15-day NDVI and EVI time series were then generated from the fitted curves and used to generate the extent of croplands. Lastly, the first derivative of the fitted VI curves were used to calculate the VI peaks;spurious peaks were removed using artificially defined thresholds and crop intensity was generated by counting the number of remaining VI peaks. The proposed methods were tested in four study regions, with results showing that 15-day time series generated from the fitted curves could accurately identify cropland extent. Overall accuracy of cropland identification was higher than 95%. In addition, both the harmonized NDVI and EVI time series identified crop intensity accurately as the overall accuracies, producer’s accuracies and user’s accuracies of non-cropland, single crop cycle and double crop cycle were higher than 85%. NDVI outperformed EVI as identifying double crop cycle fields more accurately.

关键词： crop inten sity time series sixth polyno mial fu nction harm on ized Lan dsat-8 and Sen tinel-2

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Advances in coastal ocean boundary layer detection technology and equipment in China

引用

Journal of environmental Sciences 2023年第1期123卷 156-168页

作者： Haitao Zheng Youwen Sun Tao Luo Xueling Cheng Shiyong Shao Shouyin Zheng Bangyi Tao Bin Chen Qianguang Tu Kan Huang Bingbing Wang Mian Wang Xiaoquan Song Tianshu Zhang Yin Cheng Jianguo Liu key laboratory of environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHFIPSChinese Academy of SciencesHefei 230031China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China key laboratory of Atmospheric Optics Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China Advanced Laser Technology laboratory of Anhui Province Hefei 230031China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China College of Earth Sciences University of Chinese Academy of SciencesBeijing 100049China State key laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China School of surveying and Municipal Engineering Zhejiang University of Water Resources and Electric PowerHangzhou 310018China Center for Atmospheric Chemistry Study Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3)Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China State key laboratory of Marine environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China Meteorological Observation Centre China Meteorological AdministrationBeijing 100081China College of Marine Technology Faculty of Information Science and EngineeringOcean University of ChinaQingdao 266100China

Accurate and comprehensive knowledge of the atmospheric environment and its evolution within the coastal ocean boundary layer are necessary for understanding the sources,chemical mechanisms,and transport processes of air pollution in land,sea,and *** present an overview of coastal ocean boundary layer detection technology and equipment in China and summarize the progress and main achievements in recent *** has developed a series of coastal ocean boundary layer detection technologies,including Light Detection and Ranging(LIDAR),turbulent exchange analyzer,air-sea flux analyzer,stereoscopic remote sensing of air pollutants,and oceanic aerosol detection equipment to address the technical bottleneck caused by harsh environmental conditions in coastal ocean *** in these technologies and equipment have provided scientific assistance for addressing air pollution issues and understanding land-sea-atmosphere interactions over coastal ocean regions in *** the future,routine atmospheric observations should cover the coastal ocean boundary layer of China.

关键词： Atmospheric pollution coastal ocean Atmospheric monitoring environmental instrument

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cultivated land information extraction in UAV imagery based on deep convolutional neural network and transfer learning

引用

Journal of Mountain Science 2017年第4期14卷 731-741页

作者： LU Heng FU Xiao LIU Chao LI Long-guo HE Yu-xin LI Nai-wen State key laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China College of Hydraulic and Hydroelectric Engineering Sichuan UniversityChengdu 610065China key laboratory of geo-speeial Information Technology Ministry of Land and ResourcesChengdu University of TechnologyChengdu 610059China Faculty of geosciences and environmental Engineering Southwest Jiaotong UniversityChengdu 611756China

The development of precision agriculture demands high accuracy and efficiency of cultivated land information extraction. As a new means of monitoring the ground in recent years, unmanned aerial vehicle(UAV) low-height remote sensing technique, which is flexible, efficient with low cost and with high resolution, is widely applied to investing various resources. Based on this, a novel extraction method for cultivated land information based on Deep Convolutional Neural Network and Transfer Learning(DTCLE) was proposed. First, linear features(roads and ridges etc.) were excluded based on Deep Convolutional Neural Network(DCNN). Next, feature extraction method learned from DCNN was used to cultivated land information extraction by introducing transfer learning mechanism. Last, cultivated land information extraction results were completed by the DTCLE and e Cognition for cultivated land information extraction(ECLE). The location of the Pengzhou County and Guanghan County, Sichuan Province were selected for the experimental purpose. The experimental results showed that the overall precision for the experimental image 1, 2 and 3(of extracting cultivated land) with the DTCLE method was 91.7%, 88.1% and 88.2% respectively, and the overall precision of ECLE is 90.7%, 90.5% and 87.0%, respectively. Accuracy of DTCLE was equivalent to that of ECLE, and also outperformed ECLE in terms of integrity and continuity.

关键词：卷积神经网络信息提取学习迁移无人机耕地影像实验目的提取方法

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Simulation and analysis for anthropogenic heat release

引用

Global geology 2015年第1期18卷 32-40页

作者： WANG Mingchang Matsushima Dai NIU Xuefeng LIANG Liheng LI Qiyuan College of geo-Exploration Science and Technology Jilin University Department of Architecture and Civil Engineering Chiba Institute of Technology College of Urban and environmental Sciences Changchun Normal University

Heat balance of urban ecosystem is a key point for the study of urban climate and micro-climate pattern and its change mechanism. Urban heat island effect is becoming increasingly serious,which is mainly caused by the change of the earth's surface cover and the anthropogenic heat release. In this study,the simulation experiment for the anthropogenic heat release was designed according to the heat balance principle. A set of buildings of miniature city were used to constitute the residential area,U grooves were applied to simulate the single building,and the fluorescent lamps in the U groove were regarded as the heat sources of the anthropogenic heat release. The simulation experiment was launched with long-short wave sun photometer,sonic anemothermometer and heat flow gauge in the experiment site. Then the net solar radiation,sensible heat flux and heat flux into the ground were determined. The quantities of the anthropogenic heat release were calculated based on the heat balance principle,and were compared with the theoretical power consumption of the fluorescent lamps. The root mean square error( RMSE) of the simulation for the anthropogenic heat release reaches0. 078 W·m- 2,a comparatively high precision,which showes that the anthropogenic heat release can be accurately determined through the simulation experiments. This study provided a scientific method for the purpose of monitoring the anthropogenic heat release.

关键词：仿真实验热释放城市生态系统热平衡原理城市热岛效应模拟实验感热通量太阳光度计

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：