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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

MFCC based real-time speech reproduction and recognition using distributed acoustic sensing technology

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Optoelectronics Letters 2024年第4期20卷 222-227页

作者： ZHOU Ran ZHAO Shuai luo mingming MENG Xin MA Jie LIU Jianfei School of Electronic Information Engineering Hebei University of TechnologyTianjin 300401China Tianjin Key Laboratory of Electronic Materials and Devices Hebei University of TechnologyTianjin 300401China Hebei Key Laboratory of Advanced Laser Technology and Equipment Hebei University of TechnologyTianjin 300401China

The distributed acoustic sensing technology was used for real-time speech reproduction and recognition,in which the voiceprint can be extracted by the Mel frequency cepstral coefficient(MFCC)method.A classic ancient Chinese poem“You Zi Yin”,also called“A Traveler’s Song”,was analyzed both in time and frequency domains,where its real-time reproduction was achieved with a 116.91 ms time *** smaller scaled MFCC0 at 1/12 of MFCC matrix was taken as a feature vector of each line against the ambient noise,which provides a recognition method via cross-correlation among the 6 original and recovered verse *** averaged cross-correlation coefficient of the matching pairs is calculated to be 0.5806 higher than 0.1883 of the nonmatched pairs,promising an accurate and fast method for real-time speech reproduction and recognition over a passive optical fiber.

关键词： MFCC passive coefficient

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.

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

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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

国际资本流动突然中断与货币危机——基于新兴市场国家的证据

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财经科学 2016年第4期 43-49页

作者：郑璇罗明铭湖南农业大学经济学院四川省工商银行成都营业部

国际资本流动突然中断是新兴市场国家金融开放进程中面临的重要风险,会对经济金融造成冲击,甚至可能引发货币危机。本文基于金融经济学理论和债务—通缩理论研究突然中断对货币危机的影响机理,利用新兴市场国家的样本数据进行实证检验,... 详细信息

国际资本流动突然中断是新兴市场国家金融开放进程中面临的重要风险,会对经济金融造成冲击,甚至可能引发货币危机。本文基于金融经济学理论和债务—通缩理论研究突然中断对货币危机的影响机理,利用新兴市场国家的样本数据进行实证检验,发现新兴市场国家国际资本流动突然中断对货币危机有显著的驱动作用,且一国金融开放度提高、经济增长率下降、国际储备和经常账户余额减少、国内外利差缩小和国际经济金融环境恶化将增加货币危机发生的概率。

关键词：国际资本流动突然中断新兴市场国家货币危机

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建筑隔震支座用高阻尼胶料配方的研究

橡胶工业 2021年第11期68卷 843-846页

作者：罗明明青岛农业大学建筑工程学院山东青岛266109

以天然橡胶(NR)/溴化丁基橡胶(BIIR)并用胶为主体材料制备建筑隔震支座用高阻尼胶料,考察NR/BIIR并用比、炭黑品种和用量以及增粘剂种类对胶料性能的影响。结果表明:减小NR/BIIR并用比,即增大BIIR用量可以有效增大胶料的等效阻尼比,但... 详细信息

以天然橡胶(NR)/溴化丁基橡胶(BIIR)并用胶为主体材料制备建筑隔震支座用高阻尼胶料,考察NR/BIIR并用比、炭黑品种和用量以及增粘剂种类对胶料性能的影响。结果表明:减小NR/BIIR并用比,即增大BIIR用量可以有效增大胶料的等效阻尼比,但会降低胶料的强度和形变能力;选用高比表面积的炭黑N220及增大其用量,能够有效增大胶料的等效阻尼比,但炭黑用量增大到一定程度后胶料的强度和形变能力会迅速下降;树脂类增粘剂种类对胶料性能的影响不大,但苯酚乙炔树脂会减小胶料的等效阻尼比。

关键词：高阻尼胶料建筑隔震支座胶料配方天然橡胶溴化丁基橡胶等效阻尼比

地下水流系统理论实践与野外教学应用——以三峡专业教学实习为例

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安全与环境工程 2022年第5期29卷 249-255页

作者：罗明明周宏中国地质大学(武汉)环境学院湖北武汉430078 中国地质大学(武汉)地质调查研究院湖北武汉430074

地下水流系统理论是当代水文地质学的核心框架,正在成为当代水文地质学研究的新范式。在地下水相关专业的野外实践教学中,非常有必要将地下水流系统理论的思想和相关调查研究方法融入到野外实践教学中。梳理了当前三峡专业教学实习水文... 详细信息

地下水流系统理论是当代水文地质学的核心框架,正在成为当代水文地质学研究的新范式。在地下水相关专业的野外实践教学中,非常有必要将地下水流系统理论的思想和相关调查研究方法融入到野外实践教学中。梳理了当前三峡专业教学实习水文地质教学路线存在的不足,选择三峡地区香溪河流域作为典型教学案例,对地下水流系统理论进行实践,从地下水动力条件、水化学与同位素特征等多信息渠道进行相互验证,构建了多级地下水流系统概念模型,并通过对香溪河流域多级地下水流系统案例进行教学应用,从野外现象类、工作方法类和专题调查类三个方面对野外教学知识点进行了设计,以期促进地下水流系统理论的教学,丰富并拓展三峡专业教学实习的教学资源。

关键词：地下水流系统野外实践教学设计三峡地区

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