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Distributed fiber optic sensing system for vibration monitoring of 3D printed bridges

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Optoelectronics Letters 2024年

作者： Zhao Shuai Zhou Ran luo mingming Liu Jianfei Liu Xiongfei Zhou Tao School of Electronic Information Engineering， Hebei University of Technology Tianjin Key Laboratory of Electronic Materials and Devices School of Civil Engineering and Transportation， Hebei University of Technology Tianjin Jinhang Institute of Technical Physics

The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities， including design， construction， and maintenance of bridges， tunnels， ports and other infrastructures. In this paper， a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8 m equivalent fiber segment， covering a vibration frequency from 5 Hz to 25 kHz. The sensing fiber was arranged as a “S” type layout on the bridge to recognize the standing state， windblown disturbance， and walking vibration. Moreover， the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences， respectively. The demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated 3D printed bridge， which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.

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基于光频域反射技术的风机叶片损伤识别方法研究

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激光与光电子学进展 2024年第9期61卷 229-238页

作者：董俊超罗明明刘剑飞杨文荣河北工业大学电子信息工程学院天津300401 河北省先进激光技术与装备重点实验室天津300401 天津市电子材料与器件重点实验室天津300401 河北工业大学省部共建电工装备可靠性与智能化国家重点实验室天津300401

针对传统风机叶片损伤检测中存在的定位不精确且无法在风机运行状态下进行监测的问题,提出了一种新的风机叶片损伤检测方法。该方法采用光频域反射(OFDR)技术对不同风况下风机叶片表面的应变进行测量,对应变值进行快速傅里叶变换并取其... 详细信息

针对传统风机叶片损伤检测中存在的定位不精确且无法在风机运行状态下进行监测的问题,提出了一种新的风机叶片损伤检测方法。该方法采用光频域反射(OFDR)技术对不同风况下风机叶片表面的应变进行测量,对应变值进行快速傅里叶变换并取其基频幅值获得叶片表面的应变分布,据此计算出叶片损伤的位置、长度和宽度,再根据应变大小与损伤程度的关系拟合出损伤程度判断公式,并据此识别叶片损伤程度。设计了基于OFDR的悬臂梁损伤检测实验,模拟了悬臂梁振动时的瞬时状态,根据应变分布识别出损伤的位置,验证了所提损伤识别方法的可行性。

关键词：光纤光学光频域反射背向散射光纤传感器风机叶片损伤识别应变分布

River Management and Flooding: The Lesson of December 2015–January 2016, Central USA

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Journal of Earth Science 2016年第1期27卷 117-122页

作者： Robert E.Criss mingming luo Department of Earth and Planetary Sciences Washington University in St.Louis School of Environmental Studies China University of Geosciences

The huge winter storm of December 23-29, 2015 delivered heavy rainfall in a broad swath across the USA, deluging East-Central Missouri. Record high river levels were set at many sites, but damages were most pronounced in developed floodplain areas, particularly where high levees were built or river channels greatly narrowed. An average of 20 cm of rain that mostly fell in three days impacted the entire 10 300 km2 Meramec Basin. Compared to the prior record flood of 1982, the highest relative stage（＋1.3 m） on Meramec River occurred at Valley Park proximal to（1） a new levee,（2） a landfill in the floodway,（3） large floodplain construction fills, and（4） tributary creek basins impacted by suburban sprawl. Even though only a small fraction of the 1.8 million km2 Mississippi River watershed above St. Louis received extraordinary rainfall during this event, the huge channelized river near and below St. Louis rapidly rose to set the 3rd-highest to the highest stages ever, exhibiting the flashy response typical of a much smaller river.

关键词： floods Mississippi River levees floodplain development.

Preparation and luminescence properties of monodisperse silica/aminosilane-coated Y_2O_3:Yb,Ho upconversion nanoparticles

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Chinese Science Bulletin 2011年第2期56卷 137-141页

作者： PANG Tao CAO WangHe XING mingming luo XiXian XU ShuJing Optoelectronic Technology Institute Dalian Maritime University Dalian 116026 China

Monodisperse silica/aminosilane-coated Y 2 O 3:Yb,Ho nanoparticles are prepared via homogenous precipitation combined with a polyvinylpyrrolidone-assisted ammoniation *** factors that contribute to the success of the coating are examined,and the procedure is *** with uncoated nanoparticles,coated nanoparticles exhibit an increased ratio of green to red emission intensity,which can mainly be attributed to the decreased number of surface defects induced by the surface coating.

关键词：单分散二氧化硅纳米涂层 Y2O3 氨基硅烷纳米颗粒发光性能制备上转换

Surface Flood and Underground Flood in Xiangxi River Karst Basin： Characteristics, Models, and Comparisons

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Journal of Earth Science 2016年第1期27卷 15-21页

作者： mingming luo Zhihua Chen Dechao Yin Hamza Jakada He Huang Hong Zhou Tao Wang School of Environmental Studies China University of Geosciences Wuhan 430074 China Geological Survey of China University of Geosciences Wuhan 430074 China Department of Earth and Planetary Sciences Washington University St. Louis MO 63130 USA

Xiangxi River Basin, located in western Hubei Province in central China, is a karst ridge-trough area with an inhomogeneous and complicated distribution of water resources. This paper compares the characteristics of surface and subsurface floods in this karst basin, utilizing a one-parameter Darcian model and the traditional exponential model. The observed hydrographs and inferred water components are strikingly similar for surface and subsurface floods. The Darcian model and the exponential model are based on different views of the flood generation process, with the former fitting the entire hydrograph with a single time constant, and the latter fitting only the recession limb with multiple time constants. Due to the anisotropy and heterogeneity of karst media, a combination of physical and chemical techniques including the use of 3S（remote sensing, geographical information system, global positioning system） method is proposed for an enhanced hydrological investigation to assess and characterize karst water resources in mountainous areas.

关键词： Xiangxi River karst basin surface flood underground flood hydrogeologic model recession coefficient water resource assessment.

历史遗留锰矿山老窑水来源及水体污染成因解析

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地质科技通报 2024年第5期43卷 225-234页

作者：巫政卿罗明明李宁魏世毅李大星皮景欧任文湖南省地质灾害调查监测所长沙410004 中国地质大学(武汉)环境学院武汉430078

历史遗留矿山的老窑水防治是矿山水环境治理中的难点。选取中国锰三角地区的典型锰矿区为研究对象,以查明老窑水的来源及水体污染成因。综合利用矿山水文地质调查、气象水文分析、水化学与同位素溯源等技术方法对老窑水来源和特征污染... 详细信息

历史遗留矿山的老窑水防治是矿山水环境治理中的难点。选取中国锰三角地区的典型锰矿区为研究对象,以查明老窑水的来源及水体污染成因。综合利用矿山水文地质调查、气象水文分析、水化学与同位素溯源等技术方法对老窑水来源和特征污染物进行了识别,并分析了矿区的水体污染成因模式。结果表明:研究区老窑水动态对降雨响应灵敏,老窑水主要来源于巷道和优势径流通道汇集的大气降水和含水层中的地下水;矿区矿井水、巷道水中的特征污染物为硫酸锰,矿山排水的特征污染物为硫酸钠,硫酸锰主要由硫铁矿氧化和菱锰矿溶解而形成;矿山固体废弃物淋滤入渗和老窑水的混合是区内地下水的主要污染方式,而地表水主要受矿山固体废弃物淋滤汇流、巷道口排水和矿山排水的污染。研究成果为矿山水环境治理提供了水量形成和水质演化的科学依据。

关键词：锰矿山老窑水来源识别污染成因水体污染

A method of phase demodulation of OFDR based on ARC-DSM algorithm

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Optoelectronics Letters 2022年第1期18卷 13-17页

作者： LIU Jianfei LI Chao FAN Xujun luo mingming LUAN Nannan YANG Wenrong School of Electronic Information Engineering Hebei University of TechnologyTianjin 300401China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300130China

Aiming at low stability and high harmonic distortion of the traditional phase-generated carrier(PGC)demodulation algorithm,we propose a modified demodulation algorithm for distributed strain sensing in phase-sensitive optical frequency domain reflectometry(OFDR).The proposed algorithm combines the arctangent function and differential-self-multiplying(ARC-DSM),which eliminates the effect of modulation depth and realizes the high precision strain variation *** results show that distortion and harmonic distortion are effectively suppressed by the ARC-DSM *** minimum variation of the measurable static strain is about 0.3μεand the spatial resolution can reach 0.2 m within 270 m range.

关键词： algorithm distortion phase

粤西北连州盆地构造演化对岩溶作用及岩溶塌陷的控制

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地质科技通报 2024年第4期43卷 273-290页

作者：樊燏黄琨段慧毓林宇航罗明明万军伟温汉辉曲金才张龙轩中国地质大学(武汉)环境学院武汉430078 广东省有色金属地质局九四○队广东清远511500

目前对连州盆地中生代以来的形成演化及其与岩溶发育规律的响应关系尚缺乏系统性认识。基于最新地质调查、水文地质钻探、溶蚀试验和三维地质建模,结合已有地质资料,划分了盆地构造演化阶段并探讨了各阶段岩溶作用。前白垩纪,在地壳升... 详细信息

目前对连州盆地中生代以来的形成演化及其与岩溶发育规律的响应关系尚缺乏系统性认识。基于最新地质调查、水文地质钻探、溶蚀试验和三维地质建模,结合已有地质资料,划分了盆地构造演化阶段并探讨了各阶段岩溶作用。前白垩纪,在地壳升降运动下沉积较强溶蚀能力碳酸盐岩,这为岩溶发育奠定了物质基础。印支运动促使垂向叠置地层形成EW向构造,燕山运动导致其横跨-斜跨叠加NE-SW向构造,这些地质构造控制碳酸盐岩地质结构和空间展布特征及溶蚀性能,山脉和水系分布确立,但岩溶整体不发育。白垩纪-古近纪发育陆内山间断陷汇流湖盆,地壳缓慢隆升加强了盆地周围岩溶作用,现保留早期岩溶台面。后期被冲洪积物埋藏-充填-固结成岩,岩溶基本停止发育,形成厚覆盖型红层盆地。新近纪以来,地壳快速抬升导致盆地四周山体不断抬高,河流深切,岩溶强烈发育,塑造多级岩溶台面。盆地内部分白垩系红层被剥蚀或切穿,岩溶作用复活,水系经多次变迁和贯通后,形成第四系浅覆盖型岩溶断陷盆地。构造演化控制岩溶发育规律,岩溶作用影响盆地内部结构,土体结构孕育岩溶地面塌陷。研究成果可为认识覆盖型岩溶区岩溶塌陷条件提供科学依据和指导。

关键词：连州盆地构造演化地壳活动岩溶作用岩溶塌陷

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岩溶管道与裂隙介质间溶质暂态存储机制

水科学进展 2022年第1期33卷 145-152页

作者：罗明明季怀松中国地质大学(武汉)环境学院湖北武汉430078

溶质暂态存储是岩溶地下水溶质运移过程中的普遍现象。为揭示岩溶管道与裂隙介质间溶质暂态存储机制,本文构建室内管道-裂隙物理模型,开展集中补给条件下的定量示踪试验,运用双区对流弥散模型实现溶质运移过程模拟。研究表明:随着集中... 详细信息

溶质暂态存储是岩溶地下水溶质运移过程中的普遍现象。为揭示岩溶管道与裂隙介质间溶质暂态存储机制,本文构建室内管道-裂隙物理模型,开展集中补给条件下的定量示踪试验,运用双区对流弥散模型实现溶质运移过程模拟。研究表明:随着集中补给水动力条件的增强,裂隙暂态存储水量呈线性增加趋势,溶质穿透曲线由单峰型向双峰型转变;管道和裂隙中的平均流速呈负相关关系,溶质在管道和裂隙中的滞留时间差决定了穿透曲线的形态;溶质暂态存储引发了穿透曲线的拖尾效应和双峰现象,对岩溶地下水溶质运移过程具有重要的控制作用。

关键词：溶质运移管道-裂隙物理模型暂态存储穿透曲线南方岩溶