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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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Impact of Brillouin amplification on the spatial resolution of noise-correlated Brillouin optical reflectometry

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Chinese Optics Letters 2017年第8期15卷 17-21页

作者：张明江鲍晓毅柴晶张永宁刘瑞霞刘慧刘毅张建忠 Key Lab of Advanced Transducers and Intelligent Control Systems Ministry of Education and Shanxi Province Taiyuan 030024 China Institute of Optoelectronic Engineering College of Physics&Optoelectronics Taiyuan University of Technology Taiyuan 030024 China Fiber Optics Group Department of Physics University of Ottawa Ottawa K1N 6N5 Canada

Distributed optical fiber sensors have been widely used to monitor temperature, strain, vibration, and so on. Specifically, the sensors based on Brillouin scattering have been studied extensively to measure the strain... 详细信息

关键词： Impact of Brillouin amplification on the spatial resolution of noise-correlated Brillouin optical reflectometry DFB length EDFA PRBS BFS

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

arXiv

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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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Supported black phosphorus nanosheets as hydrogen-evolving photocatalyst achieving 5.4% energy conversion efficiency at 353 K

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Nature communications 2018年第1期9卷 1397页

作者： Bin Tian Bining Tian Bethany Smith M C Scott Ruinian Hua Qin Lei Yue Tian Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan 030024 China. Department of Materials Science and Engineering University of California Berkeley Berkeley CA 94720 USA. Molecular Foundry Lawrence Berkeley National Lab Berkeley CA 94720 USA. College of Life science Dalian Nationalities University Dalian 116600 China. Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan 030024 China. tianyue@***. Molecular Foundry Lawrence Berkeley National Lab Berkeley CA 94720 USA. tianyue@***.

Solar-driven water splitting using powdered catalysts is considered as the most economical means for hydrogen generation. However, four-electron-driven oxidation half-reaction showing slow kinetics, accompanying with insufficient light absorption and rapid carrier combination in photocatalysts leads to low solar-to-hydrogen energy conversion efficiency. Here, we report amorphous cobalt phosphide (Co-P)-supported black phosphorus nanosheets employed as photocatalysts can simultaneously address these issues. The nanosheets exhibit robust hydrogen evolution from pure water (pH = 6.8) without bias and hole scavengers, achieving an apparent quantum efficiency of 42.55% at 430 nm and energy conversion efficiency of over 5.4% at 353 K. This photocatalytic activity is attributed to extremely efficient utilization of solar energy (~75% of solar energy) by black phosphorus nanosheets and high-carrier separation efficiency by amorphous Co-P. The hybrid material design realizes efficient solar-to-chemical energy conversion in suspension, demonstrating the potential of black phosphorus-based materials as catalysts for solar hydrogen production.

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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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Remote Monitoring system for Machinery-electric-hydraulic Coupling Vibration of Food Processing Rolling Mill Screw-down system

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Advance Journal of Food Science and Technology 2016年第5期10卷 360-364页

作者： Xin Liu Baoquan Jin Hongjuan Zhang Xuefeng Bai Key Lab of Advanced Transducers and Intelligent Control System Taiyuan University of Technology Ministry of Education and Shanxi Province Taiyuan 030024 China

Machinery-electric-hydraulic coupling vibration seriously affects the control accuracy of the food processing rolling mill. In this study, a remote vibration sensor monitoring method based on network technology is put forward. By using Siemens PLC, the state monitoring device is designed to realize the parameters measurement, such as vibration, current, pressure, force and temperature, etc. Then the parameter information is transferred to the configuration software system through the ethernet interface. The research result shows that the network-based remote sensor monitoring system of machinery-electric-hydraulic coupling vibration plays a key role in ensuring the normal work for food processing rolling mill screw-down system.

关键词： Configuration software food processing rolling mill machinery-electric-hydraulic coupling sensor monitoring decoupling the vibration Outcomes Research FOOD PROCESSING control accuracy remote monitoring system parametric tests Rolling mills Networking Techniques vibration sensor

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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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基于特征线—快速傅里叶变换法的轴向柱塞泵流固耦合振动特性研究（英文）

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机床与液压 2016年第6期44卷 47-52页

作者： Yang LIU Bing WU Jia-hai HUANG Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 China

Axial piston pump is fluid-solid coupling mechanical equipment. Its vibration characteristic is compli-cated when working. This paper uses the characteristic line-fast Fourier transform method （MOC - FFT） in theplunger pump to study vibration characteristics caused by fluid-solid coupling. Using the MOC to solve the fluid-solid interaction＇ s （FSI） partial differential equations （ 1 ）, then the vibration characteristics of pipeline system intime domain can be achieved. Using the fast Fourier transform method, the natural frequencies of the piping sys-tem can be obtained. It has the advantage of characteristic line method for the coupling vibration model is clear,easy to calculate; And using the method of fast Fourier transform the vibration characteristics to the frequency do-main. According to study the vibration characteristics in the frequency domain, this paper achieved the frequencywhich the type of A10V pump should be avoided when working and change rules of the angle of swash plate, pres-sure and the speed of rotation how to affect the intensive frequency vibration spectrum which is caused by the FSI.

关键词： Characteristic line-fast Fourier transform method, Axial piston pump, Fluid-solid interaction, Vibra-ion characteristics

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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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