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贵州省城市饮用水水源地保护现状评价及措施规划研究

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人民珠江 2017年第1期38卷 83-86页

作者：严涛王兴建贵州省水利水电勘测设计研究院贵州贵阳550002

随着贵州省城镇化进程的加快,城市饮用水水源地受污染的风险加大,为摸清水源地现状安全状况并提出合适的保护措施,在贵州省城市饮用水水源地全面调查的基础上,从饮用水水源地水质方面评价饮用水水源地安全状况,针对存在的问题,采取隔离... 详细信息

随着贵州省城镇化进程的加快,城市饮用水水源地受污染的风险加大,为摸清水源地现状安全状况并提出合适的保护措施,在贵州省城市饮用水水源地全面调查的基础上,从饮用水水源地水质方面评价饮用水水源地安全状况,针对存在的问题,采取隔离防护与宣传警示工程、污染综合整治工程、生态保护与修复工程三大类工程措施来开展水源地保护规划。全省133个饮用水水源地,水质综合评价合格率为96.2%。以现状评价不合格水源地和国家重要饮用水水源地为保护重点制定保护措施,规划总投资65.1亿元,为贵州省广大城镇居民构筑坚实的饮水安全防线。

关键词：城市饮用水水源地保护贵州省

基于多尺度及DESTIN约束的高分遥感影像田块语义分割方法研究

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南京农业大学学报 2024年第5期47卷 989-999页

作者：肖庆云程涛顾兴健朱艳黄芬南京农业大学人工智能学院江苏南京210031 南京农业大学国家信息农业工程技术中心/智慧农业教育部工程研究中心/农业农村部农作物系统分析与决策重点实验室/江苏省信息农业重点实验室/现代作物生产省部共建协同创新中心江苏南京210095

[目的]本研究旨在改善基于深度学习的遥感影像田块语义分割中出现的区域不封闭、边缘不贴合、噪点问题,并进一步修正语义分割的识别错误。[方法]以安徽省阜南县、江苏省淮安市为研究地点,自建了农田田块数据集,引入考虑影像多尺度特征... 详细信息

[目的]本研究旨在改善基于深度学习的遥感影像田块语义分割中出现的区域不封闭、边缘不贴合、噪点问题,并进一步修正语义分割的识别错误。[方法]以安徽省阜南县、江苏省淮安市为研究地点,自建了农田田块数据集,引入考虑影像多尺度特征的尺度分割思想与基于物候学的DESTIN(delineation by fusing spatial and temporal information)分割算法,提出了基于多尺度及DESTIN约束的高分遥感影像农田田块语义分割方法。[结果]多尺度与DESTIN约束下基于深度模型的田块语义分割有效改善模型出现的区域不封闭、边缘不贴合、噪点和块状模糊等问题,一定程度修正了深度模型语义分割的错误识别,IoU指标在2个测试集上分别达到94.08%和90.79%,相较深度模型的遥感影像田块语义分割分别提高1.65%和2.32%,对研究区域的田块提取区域更完整、精度更高。[结论]多尺度及DESTIN约束进一步改善了田块语义分割问题,有助于提高高分遥感影像的田块识别精度。

关键词：语义分割多尺度分割 DESTIN分割农田田块提取高分遥感影像

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一种适应于海外铁路客票系统的灵活型实名制方案设计

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铁路通信信号工程技术 2024年第4期21卷 70-74,80页

作者：冯涛于行健赵耀中国铁路设计集团有限公司天津300308

实名制验证是铁路客票系统的重要组成部分,它的设计深刻影响着旅客的铁路出行体验。中国现有标准的火车票实名制系统难以在海外铁路客票系统设计中移植实现,这是海外铁路建设需要解决的问题。提出一种会员制方案,用于在海外铁路客票系... 详细信息

实名制验证是铁路客票系统的重要组成部分,它的设计深刻影响着旅客的铁路出行体验。中国现有标准的火车票实名制系统难以在海外铁路客票系统设计中移植实现,这是海外铁路建设需要解决的问题。提出一种会员制方案,用于在海外铁路客票系统设计中替代中国标准的火车票实名制,有助于提升境外铁路的服务效率和运营安全。

关键词：海外铁路铁路客票实名制验证会员制

Experimental Investigation on Plasma-assisted Combustion Characteristics of Premixed Propane/Air Mixture

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Journal of Thermal Science 2015年第3期24卷 283-289页

作者： LIU xingjian HE Liming YU Jinlu ZENG Hao JIN tao Science and Technology on Plasma Dynamics Laboratory Aeronautics and Astronautics Engineering College Air Force Engineering University

A detailed study on the plasma-assisted combustion(PAC) characteristics of premixed propane/air mixture is presented. The PAC is measured electrically, as well as optically with a multichannel spectrometer. The characteristics are demonstrated by stable combustion temperature and combustion stability limits, and the results are compared with conventional combustion(CC). Stable combustion temperature measurements show that the introduction of PAC into combustion system can increase the stable combustion temperature, and the increment is more notable with an increase of discharge voltage. Besides, the rich and weak limits of combustion stability are both enlarged when plasma is applied into the combustion process and the increase of discharge voltage results in the expansion of combustion stability limits as well. The measurements of temperature head and emission spectrum illustrate that the kinetic enhancement caused by reactive species in plasma is the main enhancement pathway for current combustion system.

关键词： Plasma-assisted combustion Stable combustion temperature Combustion stability limits Mechanism

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掌上多功能超声波测厚仪的研制

武汉化工学院学报 2001年第4期23卷 72-74页

作者：杨陶李行健陈绪耀武汉化工学院自动化系湖北武汉430073 武汉大学电子信息学院湖北武汉430073 武钢冷轧厂湖北武汉430008

以实际的研制经验 ,叙述了掌上多功能超声波测厚仪采用的原理。

关键词：超声检测单片机掌上多功能超声波测厚仪

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宽带消色差平面透镜的设计与参量分析

红外与激光工程 2020年第9期49卷 53-60页

作者：肖行健祝世宁李涛南京大学现代工程与应用科学学院江苏南京210023

大尺寸、大数值孔径、宽波段的消色差平面透镜设计是成像技术的一个瓶颈性问题,也是近年来超构透镜研究领域的一个重要挑战,主要原因是透镜的各个参量之间存在内禀的制约关系。文中结合消色差透镜的群时延理论及透镜的相位分布,通过理... 详细信息

大尺寸、大数值孔径、宽波段的消色差平面透镜设计是成像技术的一个瓶颈性问题,也是近年来超构透镜研究领域的一个重要挑战,主要原因是透镜的各个参量之间存在内禀的制约关系。文中结合消色差透镜的群时延理论及透镜的相位分布,通过理论分析给出各参量之间的半定量制约关系。同时,分别通过拓扑优化和直接二值搜索的方法,设计了不同参量下的消色差超构透镜和多阶衍射透镜,发现在保持效率80%左右的前提下,透镜尺寸增加了一倍,数值孔径或波段宽度减少了一半,而透镜厚度则随尺寸成线性增长。该结果表明,这两类平面透镜具有相同的內禀参数依赖关系,即透镜尺寸与数值孔径和波段宽度呈现反相关、与透镜厚度呈现正相关的关系,这与理论预测基本一致。

关键词：平面透镜消色差参量优化

Bandpass-filter-integrated multiwavelength achromatic metalens

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Photonics Research 2021年第7期9卷 1384-1390页

作者： HANMENG LI xingjian XIAO BIN FANG SHENGLUN GAO ZHIZHANG WANG CHEN CHEN YUNWEI ZHAO SHINING ZHU tao LI National Laboratory of Solid State Microstructures Key Laboratory of Intelligent Optical Sensing and ManipulationJiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

The design of large-scale,high-numerical-aperture,and broadband achromatism is a big challenge in metalens research. In fact,many colorful imaging systems have RGB color filters,which means the achromatism only for RGB lights would be sufficient. Avoiding broadband achromatism is expected to greatly improve the working efficiency of metalenses. Nevertheless,a proper bandpass filter is necessary under a white light illumination in the metalens integrated imaging system. Here we propose a bandpass-filter-integrated multiwavelength achromatic metalens (NA=0.2),which is designed using a searching optimization algorithm to achieve the achromatism of RGB lights with high efficiencies. The bandpass filter is implemented by composite DBRs and defect layers,by which three desired wavelengths are selected out. The simulations and experiments on the filter-integrated metalens definitely show a good RGB achromatism. Further imaging experiments demonstrate a higher signal-to-noise ratio and resolution compared with the one without the filter. Our approach provides not only an RGB achromatic meta-imaging device but also a new route to access a highly efficient spectrum tailoring metasystem by incorporating bandpass filter designs.

关键词： filter lights illumination

Chip-scale metalens microscope for wide-field and depth-of-field imaging

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Advanced Photonics 2022年第4期4卷 68-75页

作者： Xin Ye Xiao Qian Yuxin Chen Rui Yuan xingjian Xiao Chen Chen Wei Hu Chunyu Huang Shining Zhu tao Li Nanjing University College of Engineering and Applied SciencesNational Laboratory of Solid State MicrostructuresKey Laboratory of Intelligent Optical Sensing and IntegrationJiangsu Key Laboratory of Artificial Functional MaterialsNanjingChina Collaborative Innovation Center of Advanced Microstructures NanjingChina

Microscopy is very important in research and industry,yet traditional optical microscopy suffers from the limited field-of-view(FOV)and depth-of-field(DOF)in high-resolution *** demonstrate a simultaneous large FOV and DOF microscope imaging technology based on a chip-scale metalens device that is implemented by a SiNxmetalens array with a co-and cross-polarization multiplexed dual-phase design and dispersive spectrum zoom effect.A 4-mm×4-mm FOV is obtained with a resolution of 1.74μm and DOF of200μm within a wavelength range of 450 to 510 nm,which definitely exceeds the performance of traditional microscopes with the same ***,it is realized in a miniaturized compact prototype,showing an overall advantage for portable and convenient microscope technology.

关键词： metalens microscope wide-field imaging

Neural network assisted high-spatial-resolution polarimetry with non-interleaved chiral metasurfaces

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Light(Science & Applications) 2023年第12期12卷 2732-2741页

作者： Chen Chen xingjian Xiao Xin Ye Jiacheng Sun Jitao Ji Rongtao Yu Wange Song Shining Zhu tao Li Nanjing University National Laboratory of Solid State MicrostructuresKey Laboratory of Intelligent Optical Sensing and ManipulationsJiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied Sciences210093 NanjingChina

Polarimetry plays an indispensable role in modern ***,the current strategies generally suffer from bulky system volume or spatial multiplexing scheme,resulting in limited performances when dealing with inhomogeneous ***,we propose a non-interleaved,interferometric method to analyze the polarizations based on a tri-channel chiral metasurface.A deep convolutional neural network is also incorporated to enable fast,robust and accurate *** uniform and nonuniform polarizations are both measured through the metasurface *** between two semblable glasses is also *** strategy features the merits of compactness and high spatial resolution,and would inspire more intriguing design for detecting and sensing.

关键词： chiral resolution polar