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Chinese Journal of Chemical Engineering 2018年第12期26卷 2628-2635页

作者： Huihui Gan futao yi Huining Zhang Yongxing Qian Huixia Jin Kefeng Zhang School of Civil Engineering and Architecture Ningbo Institute of Technology Zhejiang University College of Environmental Science and Engineering Guilin University of Technology

The Bi_4Ti_3O_(12)/g-C_3N_4 composites with microsheet and nanosheet structure were prepared through facile ultrasonic-assisted method. The SEM and TEM results suggested that the nanosheets g-C_3N_4 were stacked on the surface of regular Bi_4Ti_3O_(12) sheets. Comparing with pure Bi_4Ti_3O_(12) and g-C_3N_4, the Bi_4Ti_3O_(12)/g-C_3N_4 composites showed significant enhancement in photocatalytic efficiency for the degradation of RhB in solution. With the mass ratio of g-C_3N_4 increasing to 10 wt%, the Bi_4Ti_3O_(12)/g-C_3N_4-10% presented the best photocatalytic activity. Its photocatalysis reaction constant was approximately 2 times higher than the single component Bi_4Ti_3O_(12) or g-C_3N_4. Meanwhile, good stability and durability for the Bi_4Ti_3O_(12)/g-C_3N_4-10% were confirmed by the recycling experiment and FT-IR analysis. The possible mechanism for the improvements was the matched band positions and the effective separation of photo-excited electrons(e-) and holes(h+). Furthermore, based on the results of active species trapping, photo-generated holes(h+) and superoxide radical(·O2-) could be the main radicals in reaction.

关键词： Rhodamine B Photocatalyst Ultrasonic assisted synthesis Bi4Ti3O12 g-C3N4

FWENet:a deep convolutional neural network for flood water body extraction based on SAR images

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International Journal of Digital Earth 2022年第1期15卷 345-361页

作者： Jingming Wang Shixin Wang futao Wang yi Zhou Zhenqing Wang Jianwan Ji yibing Xiong Qing Zhao Aerospace Information Research Institute Chinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Hainan Research Institute Aerospace Information Research InstituteChinese Academy of SciencesSanyaPeople’s Republic of China School of Geography Science and Geomatics Engineering Suzhou University of Science and TechnologySuzhouPeople’s Republic of China

As one of the most severe natural disasters in the world,floods caused substantial economic losses and casualties every year.Timely and accurate acquisition of flood inundation extent could provide technical support for relevant departments in the field of flood emergency response and disaster relief.Given the accuracy of existing research works extracting flood inundation extent based on Synthetic Aperture Radar(SAR)images and deep learning methods is relatively low,this study utilized Sentinel-1 SAR images as the data source and proposed a novel model named flood water body extraction convolutional neural network(FWENet)for flood information extraction.Then three classical semantic segmentation models(UNet,Deeplab v3 and UNet++)and two traditional water body extraction methods(Otsu global thresholding method and Object-Oriented method)were compared with the FWENet model.Furthermore,this paper analyzed the water body area change situations of Poyang Lake.The main results of this paper were as follows:Compared with other five water body extraction methods,the FWENet model achieved the highest water body extraction accuracy,its F1 score and mean intersection over union(mIoU)were 0.9871 and 0.9808,respectively.This study could guarantee the subsequent research on flood extraction based on SAR images.

关键词： Deep learning flood water body extraction SAR Poyang Lake

氯掺杂g-C3N4纳米片光催化氧化染料污染物与还原六价铬的协同处理研究

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材料导报 2019年第20期33卷 3377-3382页

作者：赵文玉易赋淘甘慧慧张会宁钱勇兴靳慧霞张科锋桂林理工大学环境科学与工程学院桂林514004 宁波大学建筑工程与环境学院宁波315211 浙江大学宁波理工学院土木建筑工程学院宁波315100

以三聚氰胺与氯化铵为前驱体,通过热缩聚法和液相超声剥离法制备了纳米片状氯掺杂石墨相氮化碳(g-C3N4),采用XRD、XPS、SEM、UV-vis等手段对样品的结构及形貌进行了表征。考察了可见光下,不同改性条件下样品对Cr(Ⅵ)和罗丹明B(RhB)混合... 详细信息

以三聚氰胺与氯化铵为前驱体,通过热缩聚法和液相超声剥离法制备了纳米片状氯掺杂石墨相氮化碳(g-C3N4),采用XRD、XPS、SEM、UV-vis等手段对样品的结构及形貌进行了表征。考察了可见光下,不同改性条件下样品对Cr(Ⅵ)和罗丹明B(RhB)混合溶液的光催化降解性能。结果表明,纳米片状氯掺杂石墨相氮化碳样品对Cr(Ⅵ)和RhB混合溶液中的Cr(Ⅵ)的光催化还原效率比单一Cr(Ⅵ)溶液中提高了2.2倍,对混合溶液中RhB的光催化降解比单一RhB溶液中提高了1.4倍。分析表明改性后的纳米片状氯掺杂氮化碳具有更大的比表面积、更好的光吸收性能和电荷分离能力,改性后的样品对混合溶液中RhB的氧化降解与Cr(Ⅵ)的还原反应同时进行也更有效地促进了光生电子-空穴对分离,从而实现了两种污染物的协同降解处理。

关键词：氮化碳氯掺杂纳米片协同处理

Coupled model constructed to simulate the landslide dam flood discharge:a case study of Baige landslide dam,Jinsha River

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Frontiers of Earth Science 2020年第1期14卷 63-76页

作者： Hongjie WANG yi ZHOU Shixin WANG futao WANG Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China

Landslide dam,always triggered by the strong earthquake and heavy rain,is a common natural disaster around the world.In this study,a coupled model was built by combining DB-IWHR model and the two-dimensional hydrodynamic model to simulate the landslide dam flood discharge.We mapped the maximum Baige landslide dam flood inundated area based on Gaofen-1 imagery,and then simulated the process of Baige landslide dam flood discharge using this coupled model.It was proved that,with 80.05%F values,the coupled model was suitable to simulate the process of landslide dam flood discharge.Lastly,multiple scenarios were simulated respectively by setting varying width and depth of spillway.The results of scenarios 1-4 indicated that spillway width presented low sensibility to the peak flow in spillway and the time of its arrival,and similarly to the water depth at river cross-section and the inundated area.Water depth at river cross-section and the inundated area decreased as spillway width increased.Even if spillway width varied at 10 m interval,the average variation of water depth was less than 1.82 m and the variation of inundated area was less than 2.85%.However,the results of scenarios 5-8 indicated that spillway depth was sensitive to the peak flow in spillway and its arrival time,and also to water depth at river cross-section and the inundated area.Water depth at river cross-section and the inundated area increased first and then started to drop with spillway depth kept decreasing.When spillway depth varied at only 2 m interval,the average variation of water depth at river cross-section basically exceeded 2 m and the variation of inundated area was more than 2.85%.

关键词： landslide dam scenario simulation flood discharge

Spatial patterns of ecosystem vulnerability changes during 2001–2011 in the three-river source region of the Qinghai-Tibetan Plateau, China

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Journal of Arid Land 2016年第1期8卷 23-35页

作者： GUO Bing ZHOU yi ZHU Jinfeng LIU Wenliang WANG futao WANG Litao YAN Fuli WANG Feng YANG Guang LUO Wei JIANG Lin Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences University of Chinese Academy of Sciences

The three-river source region (TRSR, including Yangtze, Yellow and Lancang rivers), located in the Qinghai-Tibetan Plateau, China, is a typical alpine zone with apparent ecosystem vulnerability and sensitivity. In this paper, we introduced many interdisciplinary factors, such as landscape pattern indices (Shannon diversity index and Shannon evenness index) and extreme climate factors (number of extreme high temperature days, number of extreme low temperature days, and number of extreme precipitation days), to establish a new model for evaluating the spatial patterns of ecosystem vulnerability changes in the TRSR. The change intensity (CI) of ecosystem vulnerability was also analyzed. The results showed that the established evaluation model was effective and the ecosystem vulnerability in the whole study area was intensive. During the study period of 2001–2011, there was a slight degradation in the eco-environmental quality. The Yellow River source region had the best eco-environmental quality, while the Yangtze River source region had the worst one. In addition, the zones dominated by deserts were the most severely deteriorated areas and the eco-environmental quality of the zones occupied by evergreen coniferous forests showed a better change. Furthermore, the larger the change rates of the climate factors (accumulative temperature of ≥10°C and annual average precipitation) are, the more intensive the CI of ecosystem vulnerability is. This study would provide a scientific basis for the eco-environmental protection and restoration in the TRSR.

关键词： eco-environmental vulnerability climate factors spatial patterns three-river source region

Advances and application analysis of drought monitoring using remote sensing

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遥感学报 2011年第6期15卷 1315-1330页

作者： WANGLitao WANGShixin ZHOUyi WANGfutao LIUWenliang InstituteofRemoteSensingApplications ChineseAcademyofSciencesBeijingl00101China GraduateUniversi．tvofChhzeseAcademyoj’Sciences Beo＇ing100039China

在大范围、长时序的旱情监测中,遥感技术以其快速、经济和大空间范围获取的特点,弥补了基于台站气象数据旱情监测的不足,为防旱和抗旱决策提供了实时、动态、宏观的辅助决策数据。本文对已有旱情遥感监测方法进行分析和整理,将其总结为... 详细信息

在大范围、长时序的旱情监测中,遥感技术以其快速、经济和大空间范围获取的特点,弥补了基于台站气象数据旱情监测的不足,为防旱和抗旱决策提供了实时、动态、宏观的辅助决策数据。本文对已有旱情遥感监测方法进行分析和整理,将其总结为基于土壤热惯量、基于土壤波谱特征、基于蒸散模型和基于植被指数的旱情监测方法,并对各类方法从监测原理、适用范围和应用进展等方面进行了阐述。在此基础之上,详细介绍一种结合了全球植被水分指数和短波角度归一化指数的优势建立的旱情遥感监测模型和方法。以2010年春季西南地区旱情为应用案例,从监测模型方法、数据处理流程和应用分析等方面,介绍一种基于植被水分指数的旱情监测方法,并对其监测结果进行统计分析与评价。

关键词：遥感技术应用理论图像处理

IEU-Net高分辨率遥感影像房屋建筑物提取

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遥感学报 2021年第11期25卷 2245-2254页

作者：王振庆周艺王世新王福涛徐知宇中国科学院空天信息创新研究院北京100094 中国科学院大学北京100049

房屋建筑物作为人类活动的主要场所,快速准确地将其从高分辨率遥感影像中提取出来,对促进遥感信息在防灾减灾、城镇管理等方面的应用具有重要意义。本文基于深度学习,提出了高分辨率遥感影像房屋建筑物像素级精确提取方法。首先,针对样... 详细信息

房屋建筑物作为人类活动的主要场所,快速准确地将其从高分辨率遥感影像中提取出来,对促进遥感信息在防灾减灾、城镇管理等方面的应用具有重要意义。本文基于深度学习,提出了高分辨率遥感影像房屋建筑物像素级精确提取方法。首先,针对样本图像边缘像素特征不足现象,以U-Net模型为基础提出IEU-Net模型,设计了全新的忽略边缘交叉熵函数IELoss并将其作为损失函数,另外添加Dropout和BN层在避免过拟合的同时提高模型训练速度和鲁棒性。其次,为解决模型特征丰富度有限的问题,引入形态学建筑物指数MBI,与遥感影像RGB波段一同参与到模型的分类过程。最后,在模型预测时与IELoss相对应采用忽略边缘预测策略从而获得最佳建筑物提取结果。实验对比分析表明:本文方法能有效克服样本边缘像素特征不足问题并抑制道路、建筑物阴影对结果的影响,提升高分辨率遥感影像中房屋建筑物的提取精度。

关键词：深度学习 IEU-Net 高分辨率遥感影像房屋建筑物形态学建筑物指数

NSCT与GS变换的资源三号卫星数据融合方法研究与应用

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地球信息科学学报 2014年第6期16卷 949-957页

作者：秦善善王世新周艺王福涛刘文亮中国科学院遥感与数字地球研究所北京100101 中国科学院大学北京100049 桂林理工大学桂林空间信息与测绘重点实验室桂林541000

资源三号卫星遥感数据是一种新型遥感影像,目前尚未有一种专门适用于资源三号卫星融合的方法。因此,提出了一种非下采样Contourlet变换(NSCT)与Gram-Schmidt(GS)变换相结合的融合方法,将非下采样Contourlet变换增强的空间信息用于补充... 详细信息

资源三号卫星遥感数据是一种新型遥感影像,目前尚未有一种专门适用于资源三号卫星融合的方法。因此,提出了一种非下采样Contourlet变换(NSCT)与Gram-Schmidt(GS)变换相结合的融合方法,将非下采样Contourlet变换增强的空间信息用于补充具有高保真度Gram-Schmidt变换融合算法在影像清晰度方面的不足。采用线性回归的方法模拟低分辨率全色影像,将高分辨率全色影像、低分辨率全色影像及两者差值的细节影像分别进行非下采样Contourlet变换,对所得的高低频系数采取不同的融合策略进行自适应融合处理,得到新的全色影像。由低分辨率全色影像取代GS正变换第一分量,非下采样Contourlet变换得到的全色影像取代GS反变换第一分量,进行Gram-Schmidt正交变换,得到融合影像。与大多存在光谱扭曲的传统融合方法相比较,本文方法在光谱保真度、空间清晰度及地物分类精度方面都有明显的优势,说明该融合方法是一种适合资源三号卫星数据多光谱与全色影像融合的方法。

关键词：资源三号卫星非下采样Contourlet变换 Gram-Schmidt变换支持向量机低空间分辨率全色影像融合

新疆SCZ17剖面黑碳记录的16~12 ka火灾历史及其驱动因素探究

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第四纪研究 2020年第1期40卷 165-174页

作者：张曼段阜涛李刚刘依王伟赵永涛安成邦兰州大学资源环境学院西部环境教育部重点实验室甘肃兰州730000 中国气象局兰州干旱气象研究所甘肃省干旱气候变化与减灾重点实验室中国气象局干旱气候变化与减灾重点开放实验室甘肃兰州730020 中国科学院西北生态环境资源研究院沙漠与沙漠化重点实验室甘肃兰州730000

基于新疆深390 cm的SCZ17黄土剖面的黑碳(BC)记录以及总有机碳含量(TOC)和磁化率结果,并与巴里坤湖孢粉记录的温度数据对比,重建了该区末次冰消期(16~12 ka,对应剖面深度202~274 cm)的火灾历史并探讨了其控制因素。结果表明:1)在末次冰... 详细信息

基于新疆深390 cm的SCZ17黄土剖面的黑碳(BC)记录以及总有机碳含量(TOC)和磁化率结果,并与巴里坤湖孢粉记录的温度数据对比,重建了该区末次冰消期(16~12 ka,对应剖面深度202~274 cm)的火灾历史并探讨了其控制因素。结果表明:1)在末次冰消期期间黑碳通量与TOC变化具有较好的一致性,均呈上升趋势,说明随着植被量的增加,生物质燃烧活动增加;2)BC通量与湿度和温度数据的EEMD结果显示:①在13~16 ka期间,剖面的黑碳通量指示的区域生物质燃烧变化与温度变化存在着近乎同步的关系,而在12~13 ka期间可能由于湿度的影响二者的同步关系不太明确;②χfd%所指示的湿度变化和黑碳通量的对比结果显示,湿度峰值/谷值分别对应着黑碳通量的谷值/峰值,即当气候湿润时,火灾活动频率低;气候干旱时,火灾活动频率高。因此,认为研究区火灾活动倾向于发生在暖干的气候条件下,且可燃生物量可能控制着区域火灾变化的长期趋势,而由温度和湿度变化所造成的火灾活动的次一级波动叠加在这一长期趋势上。

关键词：古火灾黑碳气候变化末次冰消期新疆黄土剖面巴里坤湖

基于纹理特征的高分辨率遥感影像灾害监测应用

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灾害学 2014年第3期29卷 97-101页

作者：王丽涛王世新周艺刘文亮王峰王福涛中国科学院遥感与数字地球研究所北京100101

变化检测方法作为遥感信息获取的主要技术手段之一,在灾害监测中已得到了一定应用。然而基于遥感图像灰度信息的变化检测方法,其阈值选取受到传感器和环境因素引起的"伪变化"信息影响。由于纹理特征具有移不变特性,可以利用地物空间结... 详细信息

变化检测方法作为遥感信息获取的主要技术手段之一,在灾害监测中已得到了一定应用。然而基于遥感图像灰度信息的变化检测方法,其阈值选取受到传感器和环境因素引起的"伪变化"信息影响。由于纹理特征具有移不变特性,可以利用地物空间结构信息开展变化检测,从而避免图像灰度"伪变化"信息的影响。该文在现有变化检测技术流程之上,通过纹理特征参数的分析,结合基于贝叶斯的图像阈值分割技术,建立了基于纹理特征的高分辨率遥感影像变化检测方法,并应用在汶川地震前后的福卫-2影像,与基于光谱影像的变化检测方法进行了分析对比。

关键词：纹理特征遥感图像灾害监测变化检测