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利用高分七号影像的溢洪道自动识别

测绘通报 2024年第7期 30-34页

作者：陈佳张文李俊杰杨智文孟令奎李林宜武汉大学遥感信息工程学院湖北武汉430079 黄河水利科学研究院河南郑州450000

溢洪道是重要的水工建筑物,利用遥感影像对其进行智能识别具有重要的科学研究意义和工程应用价值。溢洪道目标对象小、背景复杂,难以与一般建筑物区分,为基于遥感影像的溢洪道目标检测带来了极大的挑战。本文利用国产高分七号卫星影像... 详细信息

溢洪道是重要的水工建筑物,利用遥感影像对其进行智能识别具有重要的科学研究意义和工程应用价值。溢洪道目标对象小、背景复杂,难以与一般建筑物区分,为基于遥感影像的溢洪道目标检测带来了极大的挑战。本文利用国产高分七号卫星影像亚米级空间分辨率优势及其立体成像能力,构建了溢洪道几何立体指数(SGSI)并提出了一种溢洪道自动识别方法。首先经过数据预处理获取融合影像和高精度DSM;然后采用均值漂移(Mean-Shift)算法对融合影像进行分割,提取出分割对象的多维特征并通过多特征联合决策确定目标对象;最后结合目标对象的空间上下文关系对溢洪道图斑进行整合和后处理,从而输出最终识别结果,实现对溢洪道的自动识别。本文选取3个含溢洪道的水库大坝对所提方法进行了验证。试验结果表明,该算法提取的溢洪道边界与参考边界匹配较好,整体精度可达89.23%,能够高效、准确地对溢洪道进行自动识别。

关键词：高分七号卫星溢洪道几何立体指数自动识别面向对象多特征联合决策

Space-confined growth of metal halide perovskite crystal films

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Nano Research 2021年第6期14卷 1609-1624页

作者： linyi li Jinxin liu Mengqi Zeng Lei Fu Country College of Chemistry and Molecular Sciences Wuhan UniversityWuhan430072China

Metal halide perovskites,as a new generation of optoelectronic materials,have attracted a great deal of interest due to their remarkable intrinsic *** to the excellent optoelectronic properties,the perovskite crystals are widely used in lasers,photodetectors,X-ray detectors and solar *** the device performance and fabrication requirements,proper thickness of the crystal is required to avoid carrier loss and simultaneously ensure sufficient light absorption,which can realize the full potential of its excellent carrier transport ***,the fabrication of perovskite crystal in a thin film with an adjustable thickness is highly *** space-confined method has been demonstrated to be an effective way of preparing perovskite with controlled *** this method,the thickness of perovskite can be regulated flexibly in a geometric confined ***,the size,quality and architecture of perovskite crystal films are also major concerns for practical photoelectric devices,which can also be optimized by the space-confined method owing to its good adaptability towards various modified *** a word,the space-confined method is not only a simple and conventional way to adjust the thickness of perovskite crystal films,but also provides a platform to optimize their size,quality and architecture through applying appropriate strategies to the confined ***,we review the space-confined growth of perovskite crystal ***,various modified strategies based on the space-confined method applied to the optimization of thickness,size,quality and architecture are *** the stability investigating and component regulating of perovskite crystal films would be also ***,the correlation between the perovskite thickness and the device performance is ***,several key challenges and proposed solutions of perovskite thin films based on the space-confined method are discussed.

关键词： space confinement metal halide perovskite thickness adjustment controllable preparation

Curvature geometry in 2D materials

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National Science Review 2023年第8期10卷 232-242页

作者： Nan Wei Yiran Ding Jiaqian Zhang linyi li Mengqi Zeng Lei Fu College of Chemistry and Molecular Sciences Wuhan University The Institute for Advanced Studies Wuhan University

The two-dimensional(2D) material family can be regarded as the extreme externalization form of the matter in the planar 2D space. These atomically thin materials have abundant curvature structures, which will significantly affect their atomic configurations and physicochemical properties. Curvature engineering offers a new tuning freedom beyond the thoroughly studied layer number, grain boundaries, stacking order,etc. The precise control of the curvature geometry in 2D materials can redefine this material family. Special attention will be given to this emerging field and highlight possible future directions. With the step-by-step achievement in understanding the curvature engineering effect in 2D materials and establishing reliable delicate curvature controlling strategies, a brand-new era of 2D materials research could be developed.

关键词： 2D materials curvature geometry deformation strain

Carbon dioxide(CO_(2))emissions from the service industry,traffic,and secondary industry as revealed by the remotely sensed nighttime light data

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International Journal of Digital Earth 2021年第11期14卷 1514-1527页

作者： Kaifang Shi Jingwei Shen Yizhen Wu Shirao liu linyi li School of Geographical Sciences Southwest UniversityChongqingPeople’s Republic of China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station Southwest UniversityChongqingPeople’s Republic of China Chongqing Engineering Research Center for Remote Sensing Big Data Application School of Geographical SciencesSouthwest UniversityChongqingPeople’s Republic of China School of Remote Sensing and Information Engineering Wuhan UniversityWuhanPeople’s Republic of China

Exploring carbon dioxide(CO2)emissions from human activities is essential for urban energy conservation and resource *** sensed nighttime lights from the Suomi NPP-VIIRS provide spatial consistency in and a low-cost way of revealing CO2 *** many researches have documented the feasibility of the Suomi NPP-VIIRS data for assessing CO2 emissions,few have systematically revealed the ability of nighttime lights for evaluating CO2 emissions from different industries,such as service industry CO2 emissions(SC),traffic CO2 emissions(TC),and secondary industry CO2 emissions(IC).Here,China was selected as the experimental subject,and we comprehensively explored the relationships between the nighttime lights and SC,TC,and IC,and investigated the factors mediating these *** found that without considering other factors,the nighttime lights only revealed up to 51.2%of TC,followed by 41.7%of IC and 22.7%of *** controlling for city characteristic variables,the models showed that there were positive correlations between the Suomi NPP-VIIRS data and SC,IC,and TC,and that nighttime lights have an Inverted-U relationship with *** Suomi NPP-VIIRS data are more suitable for revealing SC,TC,and IC in medium-sized and large-sized cities than in small-sized cities and megacities.

关键词： Nighttime light data Suomi NPP-VIIRS CO2 emissions transmission mechanism China

Experimental investigation on the invert stability of operating railway tunnels with different drainage systems using 3D printing technology

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1470-1485页

作者： linyi li Junsheng Yang Jinyang Fu Shuying Wang Cong Zhang Maolong Xiang School of Civil Engineering Central South UniversityChangsha410075HunanChina National Engineering Research Center of High-speed Railway Construction Technology Changsha410075China School of Civil Engineering Central South University of Forestry and TechnologyChangsha410004China

In recent years, the invert anomalies of operating railway tunnels in water-rich areas occur frequently,which greatly affect the transportation capacity of the railway lines. Tunnel drainage system is a crucial factor to ensure the invert stability by regulating the external water pressure(EWP). By means of a threedimensional(3D) printing model, this paper experimentally investigates the deformation behavior of the invert for the tunnels with the traditional drainage system(TDS) widely used in China and its optimized drainage system(ODS) with bottom drainage function. Six test groups with a total of 110 test conditions were designed to consider the design factors and environmental factors in engineering practice,including layout of the drainage system, blockage of the drainage system and groundwater level fluctuation. It was found that there are significant differences in the water discharge, EWP and invert stability for the tunnels with the two drainage systems. Even with a dense arrangement of the external blind tubes, TDS was still difficult to eliminate the excessive EWP below the invert, which is the main cause for the invert instability. Blockage of drainage system further increased the invert uplift and aggravated the track irregularity, especially when the blockage degree is more than 50%. However, ODS can prevent these invert anomalies by reasonably controlling the EWP at tunnel bottom. Even when the groundwater level reached 60 m and the blind tubes were fully blocked, the invert stability can still be maintained and the railway track experienced a settlement of only 1.8 mm. Meanwhile, the on-site monitoring under several rainstorms further showed that the average EWP of the invert was controlled within 84 k Pa, while the maximum settlement of the track slab was only 0.92 mm, which also was in good agreement with the results of model test.

关键词： Operating railway tunnels Invert stability Tunnel drainage system Three-dimensional(3D)printing technology Model test

Spatial and temporal variabilities of rainstorms over China under climate change

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Journal of Geographical Sciences 2021年第4期31卷 479-496页

作者： HUANG Chang ZHANG Shiqiang DONG linyao WANG Zucheng li linyi CUI Luming Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi'an 710127China Institute of Earth Surface System and Hazards Northwest UniversityXi'an 710127China College of Urban and Environmental Sciences Northwest UniversityXi'an 710127China Changjiang River Scientific Research Institute Wuhan 430010China State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration Institute for Peat&Mire ResearchNortheast Normal UniversityChangchun 130021China School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430070China

Rainstorms are one of the extreme rainfall events that cause serious disasters,such as urban flooding and mountain *** studies have used rain gauge observations to analyze rainstorm events,but relevant information is usually missing in gauge-sparse ***-derived precipitation datasets serve as excellent supplements or substitutes for the gauge *** developing a grid-based rainstorm-identification tool,we used the Tropical Rainfall Measurement Mission(TRMM)Multi-satellite Precipitation Analysis(TMPA)time series product to reveal the spatial and temporal variabilities of rainstorms over China during 1998–*** patterns of both increasing and decreasing rainstorm occurrences were detected,with no spatially uniform trend being observed across the whole *** was an increase in the area being affected by rainstorms during the 20-year period,with rainstorm centers shifting along the southwest–northeast *** occurrence was found to be correlated with local total *** comparing rainstorm occurrence with climate variables such as the El Ni?o-Southern Oscillation and Pacific Decadal Oscillation,we also found that climate change was likely to be the primary reason for rainstorm occurrence in *** study complements previous studies that used gauge observations by providing a better understanding of the spatiotemporal dynamics of China’s rainstorms.

关键词： climate change extreme precipitation meteorology rainfall satellite precipitation data

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基于STM32的室内照明系统设计

智能建筑电气技术 2024年第1期18卷 27-30页

作者：李林宜汪静远程绍峰李艳波长安大学能源与电气工程学院西安710061 中国兵器工业集团航空弹药研究院哈尔滨150030

为了实现节约能源、促进绿色发展,本设计以STM32F103系列单片机为核心设计的智能室内照明系统,通过红外热释电传感器检测周围环境是否有人员进出,声音传感器检测声音信号,光敏电路检测周围的光线亮度来控制台灯的点亮时间,并根据不同时... 详细信息

为了实现节约能源、促进绿色发展,本设计以STM32F103系列单片机为核心设计的智能室内照明系统,通过红外热释电传感器检测周围环境是否有人员进出,声音传感器检测声音信号,光敏电路检测周围的光线亮度来控制台灯的点亮时间,并根据不同时间段照明需求改变照明光强。将这些模拟量信号传输入单片机再利用单片机内部的A/D转换模块将模拟量转换成数字量,利用PWM对LED灯亮度进行实时控制与调节,最终在硬件平台上测试证明该照明系统的有效性。

关键词： STM32 照明系统 PWM

A cell-based fluorescent glucose transporter assay for SGLT2 inhibitor discovery

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Acta Pharmaceutica Sinica B 2013年第2期3卷 97-101页

作者： Yi Huan linyi li Quan liu Shuainan liu Zhufang Shen State Key Laboratory of Bioactive Substances and Functions of NaturalMedicines Diabetes Research CenterInstituteof Materia MedicaChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100050China

The sodium/glucose cotransporter 2(SGLT2)is responsible for the majority of glucose reabsorption in the kidney,and currently,SGLT2 inhibitors are considered as promising hypoglycemic agents for the treatment of type 2 diabetes *** constructing CHO cell lines that stably express the human SGLT2 transmembrane protein,along with a fluorescent glucose transporter assay that uses 2-[N-(7-nitrobenz-2-oxa-l,3-diazol-4-yl)amino]2-deoxyglucose(2-NBDG)as a glucose analog,we have developed a nonradioactive,cell-based assay for the discovery and characterization of SGLT2 inhibitors.

关键词： SGLT2 inhibitor NBDG Type 2 diabetes mellitus Kidney

Improved Visible-light Photocatalytic Properties of ZnFe2O4 Synthesized via Sol-gel Method Combined with a Microwave Treatment

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Chemical Research in Chinese Universities 2015年第3期31卷 439-442页

作者： FENG Jing WANG Yuting ZOU linyi li Bowen HE Xiaofeng Lü Shengna CHEN Tingting Key Laboratory of Superlight Materials & Surface Technology Ministry of Education Harbin Engineering University Harbin 150001 P. R. China

ZnFe2O4（ZFO） was synthesized via a sol-gel method firstly, then the ZFO was irradiated with microwave treatment to obtain M-ZFO using NH4C1 as dispersant for 10 min to improve the photocatalytic activity. Large par- tides of ZFO were broken into small and uniform particles by the gases of hydrogen chlorine and ammonia during the decomposition of NH4Cl. Compared to ZnFe2O4 without microwave treatment（ZFO）, M-ZFO exhibits smaller particle size, higher surface area and larger saturation magnetization. More importantly, the photocatalytic activity of M-ZFO for methylene blue was increased by 25% compared with that of ZFO.

关键词： Photocatalyst Microwave treatment ZnFe2O4