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Distributed fiber temperature sensor using a laser diode modulated by a pseudo-random bit sequence

Chinese Optics Letters 2015年第8期13卷 23-26页

作者：柴晶张明江刘毅李岚许卫鹏王云才 Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology Institute of Optoelectronic Engineering College of Physics and OptoelectronicsTaiyuan University of Technology

We propose and demonstrate a scheme to measure the distribution of temperature along an optical fiber based on pseudo-random sequence modulation. In our experimental work, current modulation with a pseudo-random bit sequence （PRBS） is applied to a laser diode that serves as the Brillouin pump light and reference light. Because of the independence of the spatial resolution on the PRBS length~ the measurement range can be extended while maintaining high spatial resolution using a long PRBS length. Temperature-induced changes in a Brillouin frequency shift of 250 m fiber sections are clearly observed with 54 cm spatial resolution by this method.

关键词： Image resolution Modulation Optical fibers

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Experimental investigation of a UWB direct chaotic through-wall imaging radar using colpitts oscillator

Experimental investigation of a UWB direct chaotic through-w...

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IET International Radar Conference 2015

作者： L. Liu R. X. Ma H. Xu W. K. Wang B. J. Wang J. X. Li Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province

ISBN: (纸本)9781510822023

An ultra-wideband direct chaotic through-wall imaging radar is proposed and experimentally demonstrated. The chaotic signal is generated by an improved Colpitts oscillator. Target range information is achieved by the cross-correlation between the time-delayed reflected echo signal and the replica of the transmitted chaotic signal. Two-dimensional image is obtained by synthetic aperture technology and back projection algorithm. Experimental results of single target and double targets show that the proposed chaotic radar system can through 20cm thick wall to detect and locate the target.

关键词： Through-wall radar Chaotic radar UWB Colpitts oscillator Synthetic aperture

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Research on the Performance of Hydraulic Excavator with Pump and Valve Combined Separate Meter In and Meter Out Circuits

Research on the Performance of Hydraulic Excavator with Pump...

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2015 International Conference on Fluid Power and Mechatronics

作者： Lei Ge Zhixin Dong Weinan Huang Long Quan Jing Yang Wenyong Li Taiyuan University of Technology Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education

Conventional hydraulic actuator is controlled by mechanically connected orifices valve. The controllability of this method is poor and the energy consumption is huge especially under the over-running condition. So a novel system configuration of the hydraulic excavator is presented to improve the problem mentioned above, in which boom cylinder, stick cylinder and swing motor are controlled with separate meter in and meter out technology, bucket cylinder and travel motors are controlled with conventional valves. Firstly, the paper provides a comprehensive review on the development of the separate meter in and meter out technology. Then the principles of load sensing system and SMISMO system applied on the excavator are illustrated though two diagram to show the difference of the two systems. And then a virtual prototype based on the real physical structures is established, which consists of the hydraulic excavator mechanical structure with multi-body dynamics and electro-hydraulic system. The model is verified by the statics and dynamics experiments. Then the dynamic, static performances as well as the energy consumption characteristics of the boom, arm and swing actuators are investigated under the condition of load sensing hydraulic system and the proposed system using the virtual prototype. The control strategy of the actuators is formulated according to their load condition and operation characteristics also based on the detailed analysis. After that, the physical prototype based on the proposed configuration system is established and its performance is tested. The experimental results show that the accuracy of the virtual prototype is validated;the proposed configuration system can significantly decreases the pressure losses through the valve and improve the energy efficiency of the machine;the pressure shocks within hydraulic actuators is decreased as well, thus the stationarity of the whole machine is improved accordingly.

关键词： flow matching separate meter in and meter out pressure and flow combined control pump and valve hybrid control

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Dynamic hazard of belt transport tracking and discerning method based on mean shift

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International Journal of Mining and Mineral Engineering 2015年第4期6卷 309-320页

作者： Qiao, Tiezhu Duan, Yanfei Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan030024 China

For the conveyer belt in coal mine often damaged by hazards such as stones or metals in transit which can cause a longitudinal tear, and the feature of hazards' status changed when transportation belt being torn, a Mean shift tracking and monitoring method was approached. Infrared spectrum imaging model was established for hazard, and extracted hazard grey value according to reflected background radiation differences between hazard and coal in the best wavelength range. Hazard model is established using grey space joint histogram, Mean shift vector is established with bandwidth matrix and recursive equations are given in EM like manner. Experiments show that when hazards tearing the tape, the algorithm can be real-time tracking and monitoring the state of hazards to determine the tape tear. © 2015 Inderscience Enterprises Ltd.

关键词： Image processing

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Transient Flow Field Characteristic Analysis of Poppet Valve Based on Dynamic Mesh 6DOF Technique

Transient Flow Field Characteristic Analysis of Poppet Valve...

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2015 International Conference on Fluid Power and Mechatronics

作者： Guo Xiao-xia Huang Jia-hai Quan Long Wang Sheng-guo Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

In the fluid engineering, many projects involve movement and deformation of the boundary, but it is difficult to describe them by a simple algebraic expression because the movement of the boundary is determined by the force of hydraulic pressure, torque and other force which work together on the boundary. However, the previous numerical analyses are limited to the steady method or directly giving a speed to the spool which is difficult to actually simulate the movement of the spool. This paper developed a 6DOF model of a threedimensional poppet valve to stimulate the transient flow field in the opening process by means of computational fluid dynamics software—Fluent. The movement of the spool is decided by fluid force which exert on it and its gravity. By comparing numerical simulation results of the valve displacement, pressure of the control chamber and the inlet and outlet flow rate of poppet valve with the experimental results, the numerical results are the same as the experimental results. So the method that the paper proposed is feasible and more truly to simulate the flow state in the opening process of hydraulic valve. And on this basis, the pressure field, velocity field and flow regime are researched when poppet valve reaches steady state, which provides an important theoretical basis for further research on hydraulic valve performance.

关键词： poppet valve numerical calculation Dynamic Mesh Fluent

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Research on the performance of hydraulic excavator with pump and valve combined separate meter in and meter out circuits

Research on the performance of hydraulic excavator with pump...

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International Conference on Fluid Power and Mechatronics (FPM)

作者： Lei Ge Zhixin Dong Weinan Huang Long Quan Jing Yang Wenyong Li Taiyuan University of Technology Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan China

ISBN: (纸本)9781479987719

Conventional hydraulic actuator is controlled by mechanically connected orifices valve. The controllability of this method is poor and the energy consumption is huge especially under the over-running condition. So a novel system configuration of the hydraulic excavator is presented to improve the problem mentioned above, in which boom cylinder, stick cylinder and swing motor are controlled with separate meter in and meter out technology, bucket cylinder and travel motors are controlled with conventional valves. Firstly, the paper provides a comprehensive review on the development of the separate meter in and meter out technology. Then the principles of load sensing system and SMISMO system applied on the excavator are illustrated though two diagram to show the difference of the two systems. And then a virtual prototype based on the real physical structures is established, which consists of the hydraulic excavator mechanical structure with multi-body dynamics and electro-hydraulic system. The model is verified by the statics and dynamics experiments. Then the dynamic, static performances as well as the energy consumption characteristics of the boom, arm and swing actuators are investigated under the condition of load sensing hydraulic system and the proposed system using the virtual prototype. The control strategy of the actuators is formulated according to their load condition and operation characteristics also based on the detailed analysis. After that, the physical prototype based on the proposed configuration system is established and its performance is tested. The experimental results show that the accuracy of the virtual prototype is validated; the proposed configuration system can significantly decreases the pressure losses through the valve and improve the energy efficiency of the machine; the pressure shocks within hydraulic actuators is decreased as well, thus the stationarity of the whole machine is improved accordingly.

关键词： Valves Actuators Prototypes Energy consumption Cavity resonators Load modeling

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Characteristics of a Piloted Digital Flow Valve Based on Flow Amplifier

Characteristics of a Piloted Digital Flow Valve Based on Flo...

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2015 International Conference on Fluid Power and Mechatronics

作者： Taotao Li Jiahai Huang Yanhong Bai Long Quan Shengguo Wang Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

Hydraulic switching techniques which have less throttling losses, good repeatability and can be controlled intelligently have been largely developed. The biggest challenge is the hydraulic fluctuation. It is generated in the process of opening and closing the valve. A two-stage digital flow valve operated by Pulse Width Modulation(PWM) signal is studied in this paper. The main stage is cartridge valve based on flow amplifying principle;the pilot stage is high-speed on/off valve. The fluctuation characteristic of the digital flow valve is investigated using theoretical derivation and simulation analysis. The results show that the outlet flow fluctuation is influenced by many parameters such as the frequency and duty ratio of PWM signal, the volume of control chamber, etc. It can be weakened through the proper design of these parameters. Although the fluctuation exists, the mean outlet flow can be proportionally controlled by adjustment of the duty ratio of the control signal.

关键词： Flow valve,High-speed on/off valve,PWM,cartridge valve

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Cover Feature: Ultrasensitive, Sustainable, and Selective Electrochemical Hydrazine Detection by ALD-Developed Two-Dimensional WO3(ChemElectroChem 2/2018)

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ChemElectroChem 2017年第2期5卷

作者： Zihan Wei Zhenyin Hai Mohammad Karbalaei Akbari Prof. Jie Hu Lachlan Hyde Prof. Stephen Depuydt Prof. Francis Verpoort Prof. Serge Zhuiykov Ghent University Global Campus Department of Applied Analytical & Physical Chemistry 119 Songdomunhwa-ro Yeonsu-gu Incheon South Korea Micro and Nano System Research Center Key Lab of Advanced Transducers and Intelligent Control System (Ministry of Education) & College of Information Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi PR China Factory of the Future Swinburne University of Technology Hawthorn Australia National Research Tomsk Polytechnic University Lenin Avenue 30 634050 Tomsk Russian Federation Laboratory of Organometallics Catalysis and Ordered Materials State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Center for Chemical and Material Engineering Wuhan University of Technology Wuhan P.R. China

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Chaotic light generation and its application in communication, sensor, radar

Chaotic light generation and its application in communicatio...

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International Conference on Optical Communications and Networks (ICOCN)

作者： Mingjiang Zhang Anbang Wang Yuncai Wang Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan Shanxi CN

Chaotic light has aroused considerable interest owing to its wide applications. Semiconductor laser, subject to optical feedback, optical injection, or optoelectronic feedback, can readily emit large-amplitude optical chaotic signals, and hence become the most suitable chaotic light sources. This paper illustrates the chaotic light generation based on semiconductor laser and its application in optical time domain reflectometry, distributed fiber sensing and photonic UWB radar.

关键词： Chaotic communication Optical feedback Optical fibers Optical attenuators Optical fiber sensors Optical reflection

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Synchronous Consensus of Double-Integrator Continuous-Time Multi-Agent systems with Switching Topologies and Time-Varying Delays

Synchronous Consensus of Double-Integrator Continuous-Time M...

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IEEE Annual Conference on Decision and control

作者： Hajar Atrianfar Mohammad Haeri Electrical Engineering Department Amirkabir University of Technology Tehran Iran Advanced Control System Lab Electrical Engineering Department Sharif University of Technology Tehran Iran

ISBN: (纸本)9781479978878

In this paper, we propose a class of second-order continuous-time consensus protocols in networks with bounded communication delay and switching interaction topologies. We present a sufficient condition under which the information states of all agents approach common values. The convergence analysis relies on properties ofnonnegative matrices and graph theory and requires that the union of communication graphs has a spanning tree over a bounded period of time. In addition, convergence in leader-following consensus is proved for switching topology and time-varying agents' awareness. Also the appropriate feedback gains are computed via given mathematical relations.

关键词： Multi-agent systems Time-varying delays Double-integrator continuous-time systems Synchronous consensus Switching topologies Leader-following

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