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Distributed optical fiber sensor using Sagnac for acoustic detection

Journal of Measurement Science and Instrumentation 2017年第1期8卷 84-88页

作者： WANG Yun-cai GONG Li-shuang JIN Bao-quan WANG Dong WU Rui-dong WANG Yu Key Laboratory of Advanced Transducers and Intelligent Control Systems Ministry o f Education Taiyuan University of Technology Taiyuan 030024 China State Key Laboratory of Coal and CBM Co-mining Jincheng 048000 China

A distributed optical fiber acoustic sensor based on in-line Sagnac is *** clockwise and counterclockwise light waves are recombined,interference in3X3coupler is *** acoustic sensor uses photo detector(PD),data acquisition card,filter and amplification to realize photo electric conversion and recover acoustic *** study the performance of this acoustic sensor,localization principle based on null frequency is *** reveal null frequencies from the acoustic disturbance position,a fast Fourier transform(F F T)is applied to transform time domain signal data into frequency domain *** results demonstrate that the Sagnac distributed optical fiber sensor can retransmit acoustic signal and the location performance is verified by simulation and experiment.

关键词： Sagnac acoustic sensor null frequency localization

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Chaotic brillouin optical correlation domain analysis

arXiv

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arXiv 2017年

作者： Zhang, Jianzhong Zhang, Mingtao Zhang, Mingjiang Yi, L.I.U. Feng, Changkun Wang, Yahui Wang, Yuncai Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan030024 China Institute of Optoelectronic Engineering College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan030024 China

We propose and experimentally demonstrate a chaotic Brillouin optical correlation-domain analysis (BOCDA) system for distributed fiber sensing. The utilization of the chaotic laser with low coherent state ensures high spatial resolution. The experimental results demonstrate a 3.92-cm spatial resolution over a 906-m measurement range. The uncertainty in the measurement of the local Brillouin frequency shift is ＋ 1.2 MHz. The measurement signal-to-noise ratio is given, which is agreement with the theoretical value. © 2017 Optical Society of America Copyright © 2017, The Authors. All rights reserved.

关键词： Signal to noise ratio

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Time delay signature elimination of chaos in a semiconductor laser by dispersive feedback from a chirped FBG

arXiv

引用

arXiv 2017年

作者： Wang, Daming Wang, Longsheng Zhao, Tong Gao, Hua Wang, Yuncai Chen, Xianfeng Wang, Anbang Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan030024 China School of Electronic Engineering Bangor University BangorLL571UT United Kingdom

—Time delay signature (TDS) of a semiconductor laser subject to dispersive optical feedback from a chirped fiber Bragg grating (CFBG) is investigated experimentally and numerically. Different from mirror, CFBG provides additional frequency-dependent delay caused by dispersion, and thus induces external-cavity modes with irregular mode separation rather than a fixed separation induced by mirror feedback. Compared with mirror feedback, the CFBG feedback can greatly depress and even eliminate the TDS, although it leads to a similar quasi-period route to chaos with increases of feedback. In experiments, by using a CFBG with dispersion of 2000ps/nm, the TDS is decreased by 90% to about 0.04 compared with mirror feedback. Furthermore, both numerical and experimental results show that the TDS evolution is quite different: the TDS decreases more quickly down to a lower plateau (even background noise level of autocorrelation function) and never rises again. This evolution tendency is also different from that of FBG feedback, of which the TDS first decreases to a minimal value and then increases again as feedback strength increases. In addition, the CFBG feedback has no filtering effects and does not require amplification for feedback *** Codes 37D45 (Primary), 37N20, 78A60 (Secondary) Copyright © 2017, The Authors. All rights reserved.

关键词： Time delay

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Load Curve Modeling Based on Behavior Analysis of Distributed Power Customers

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IOP Conference Series: Materials Science and Engineering 2019年第1期486卷

作者： Xinyang Han Yu Zhang Yuqiao Jiao Yue Zhang Yanjing Qu Min Ding State Grid Energy Research Institute Beijing 102200 P. R. China 027-8883018 School of Automation China University of Geosciences Wuhan 430074 P. R. China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex System Wuhan 430074 P. R. China State Grid Shanghai Municipal Electric Power Company Shanghai 200122 P. R. China

As renewable power generation directly affects the customers' traditional electricity behavior and then offsets the power load, this paper proposes a load curve modeling method for renewable power customers based on the behavior analysis. Firstly, customers' active behavior is represented by the quantity of active customer households. Based on the analysis of customer behaviors, a modeling method for the quantity of active customer households is proposed based on Markov Chain Monte Carlo method. Then, with the inputs as the quantity of active customer households and time of photovoltaic power generation, an inference model based on fuzzy logic is proposed to get the quantity of customer household starting electrical appliances. By combing the average usage time of electrical appliances, load characteristics are analyzed based on usage state of electrical appliance of distributed power customers. Finally, the simulation results verify the effectiveness of the proposed method.

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Gas adsorption and accumulation on hydrophobic surfaces:Molecular dynamics simulations

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Chinese Physics B 2015年第9期24卷 392-398页

作者：骆庆群杨洁明 Taiyuan University of Technology Key Laboratory Advanced Transducers and Intelligent Control System of Ministry of Education

Molecular dynamics simulations show that the gas dissolved in water can be adsorbed at a hydrophobic interface and accumulates thereon. Initially, a water depletion layer appears on the hydrophobic interface. Gas molecules then enter the depletion layer and form a high-density gas-enriched layer. Finally, the gas-enriched layer accumulates to form a nanobubble. The radian of the nanobubble increases with time until equilibrium is reached. The equilibrium state arises through a Brenner–Lohse dynamic equilibrium mechanism, whereby the diffusive outflux is compensated by an influx near the contact line. Additionally, supersaturated gas also accumulates unsteadily in bulk water, since it can diffuse back into the water and is gradually adsorbed by a solid substrate.

关键词： hydrophobic molecular dynamics nanobubble

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Identification of mining steel rope broken wires based on improved EEMD

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International Journal of Mining and Mineral Engineering 2016年第3期7卷 224-236页

作者： Qiao, Tie-Zhu Li, Zhao-Xing Jin, Bao-Quan Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan030024 China

Metal magnetic memory (3M), which is used to evaluate the stress concentration and fatigue damage of ferromagnetic materials, belongs to a weak magnetic detection. When 3M technology is used to detect working steel rope, the detected signal contains lots of interfering signals to distort real signal. To improve signal to noise ratio (SNR), ensemble empirical mode decomposition (EEMD) is used to denoise the original signal. A new method of confirming white noise standard deviation (WNSD) added to EEMD has been proposed, which has a higher accuracy. Besides, a self-adaptive method of selecting intrinsic mode functions (IMFs) has been proposed. The method is used to denoise magnetic memory signal of steel rope metal and the result is better than other common denoising methods. After denoising the tested signal of steel rope, the broken wires field of the rope can be recognised by the normal component of 3M crossing zero point. © 2016 Inderscience Enterprises Ltd.

关键词： Empirical mode decomposition

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Electric field effect in ultrathin zigzag graphene nanoribbons

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Chinese Physics B 2015年第7期24卷 356-359页

作者：张文星刘云霄田华许军伟冯琳 Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of EducationPhysics DepartmentTaiyuan University of Technology

The electric field effect in ultrathin zigzag graphene nanoribbons containing only three or four zigzag carbon chains is studied by first-principles calculations, and the change of conducting mechanism is observed with increasing in-plane electric field perpendicular to the ribbon. Wider zigzag graphene nanoribbons have been predicted to be spin-splitted for both valence band maximum（VBM） and conduction band minimum（CBM） with an applied electric field and become half-metal due to the vanishing band gap of one spin with increasing applied field. The change of VBM for the ultrathin zigzag graphene nanoribbons is similar to that for the wider ones when an electric field is applied. However, in the ultrathin zigzag graphene nanoribbons, there are two kinds of CBMs, one is spin-degenerate and the other is spin-splitted, and both are tunable by the electric field. Moreover, the two CBMs are spatially separated in momentum space. The conducting mechanism changes from spin-degenerate CBM to spin-splitted CBM with increasing applied electric field. Our results are confirmed by density functional calculations with both LDA and GGA functionals, in which the LDA always underestimates the band gap while the GGA normally produces a bigger band gap than the LDA.

关键词： electric field density functional theory zigzag nanoribbon

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Distributed sensor diagnosis for wire fault of complex topology wired networks based on chaos-TDR

Distributed sensor diagnosis for wire fault of complex topol...

引用

Progress in Electromagnetic Research Symposium (PIERS)

作者： Bingjie Wang Hang Xu Yuncai Wang Guanghui Wu Li Liu Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan 030024 China

ISBN: (纸本)9781509060948

The growing need for wiring in avionics, automotive, telecommunications, nuclear plants, buildings, etc., has caused the increase of the complexity of wired networks. This also leads to the increase of the difficulty of their maintenance that becomes not only problematic but also expensive. The need of embedded diagnosis to perform continuous monitoring was identified. Although reflectometry is an efficient method to diagnose simple topologies, it remains limited in the case of complex branched networks due to multipath fading of the test signal during its propagation. In practice, a distributed diagnosis strategry is necessary when multiple reflectometers (referred as diagnosis sensors) at several points of a complex network at the same time, thus allowing to solve ambiguities due to the existence of multiple paths and to guarantee a reliable and continuous diagnosis in complex wiring system. In this paper, the use of chaotic signals for distributed diagnosis and the detection of defects in the complex wiring network is presented experimentally. Chaos time-domain reflectometry (chaos-TDR) using low auto-correlation sidelobes signals, shows high performances in very noisy environment and is a suitable candidate for on-line diagnosis. Low cross-correlation chaotic signals enable several reflectometers (sensors) to simultaneously inject their signals in the cables, without any interference. Experimental results show that the proposed method performs well in a branched wiring network as it permits to detect and locate faults accurately even when the target system is operating. Also, the inference of wired network topology is realized by using sensor measurements at multiple cable ends.

关键词： Wiring Network topology Topology Electromagnetics Wires transducers intelligent control

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Surface Plasmon Assisted Organic Photovoltaic Cells

Surface Plasmon Assisted Organic Photovoltaic Cells

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第三届新型太阳能电池学术研讨会

作者： Yanxia Cui Yuying Hao Peiqian Tong Fan Yang Yang Hao Furong Zhu Key Laboratory of Advanced Transducers and Intelligent Control System (Ministry of Education) Taiyuan University of Technology Department of Physics and Institute of Advanced Materials Hong Kong Baptist University

Organic photovoltaic(OPV)cells have been thoroughly investigated in the past decade owing to the advantages of low cost,flexibility,light weight,easy fabrication,semi-transparency and colorfulness,*** the efficiency o... 详细信息

关键词： OPV PCE Surface Plasmon Assisted Organic Photovoltaic Cells

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Investigation of Correlation between the Temperature on Air-Snow and Snow-Ice Interfaces and the Atmospheric Air Temperature

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Journal of Earth Science and Engineering 2016年第5期6卷 245-253页

作者： Vadim K. Goncharov Natalia Yu. Edush Ekaterina S. Zueva Natalia Yu. Klementeva Jianmin Qin Liqin Cui Li Zhang Xiao Deng Peng Cheng State Marine Technical University of Saint-Petersburg Russia Krylov State Research Centre Saint-Petersburg Russia College of Physics and Optoelectronic Taiyuan University of Technology Taiyuan China Key Laboratory Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of TechnologyTaiyuan China

Solution of the practical problems of the ice engineering requires the data about the strength of the ice cover that depends upon its temperature. In most cases, the snow lies on the ice cover and the ice temperature differs from the atmospheric air temperature. To reveal the correlation of the air temperature with temperature on interfaces air-snow and snow-ice, the known in the thermophysics solution of the problem of the heat transfer through the multilayer plate was applied. Derived solution connects the temperature of air and temperature on the snow-ice interface and satisfactory correlates with data of the field measurements of the temperature within snow layer and ice cover and ice thickness on the Heilongjiang （Amur） River. Results of investigation are recommended for the ice temperature evaluation in engineering practice.

关键词： Snow ice air temperature interface ice thickness.

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