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Optical-fiber distributed temperature sensor:design and realization

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Optoelectronics Letters 2008年第6期4卷 415-418页

作者： MENG Ling JIANG Ming-shun SUI Qing-mei FENG De-jun School of Control Science and Engineering Shandong University Jinan 250061 China information industry promotion agency Shandong Province Information Office Jinan 250000 China School of information Science and Engineering Shandong University Jinan 250100 China

Through analyzing theoretically the temperature effect of the optical-fiber Raman backscattering,a distributed temperature sensor is designed based on the single-mode fiber. Demodulation methods of temperature transduction are compared,and then the demodulation method using the ratio of the anti-Stokes and the Stokes Raman backscattering intensity is adopted. Both the hardware composition and the software realization of the system are introduced in detail. The experiment shows that the distinguishing ability of the temperature and that of the space are 1℃ and 2m,respectively,and that the system response time is about 180 s with a sensing range of 5km and with a temperature measurement range of 0-100℃.

关键词：光纤分布温度敏感度信号传输计算机技术

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New Frequency Standard Comparison System Based on the Group Quantization Phase Processing

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Chinese Journal of Electronics 2019年第2期28卷 392-397页

作者： DU Baoqiang DENG Ran SUN Xiyan FU Qiang School of Electronic information Engineering Zhengzhou University of Light Industry School of information and Communication Guilin University of Electronic Technology

A new frequency standard comparison system is proposed based on the group quantization phase processing. By shortening the width of phase coincidence fuzzy area and capturing the best group phase coincidences, we reduce the randomness of the counting gate and improve the measurement precision of the comparison system. The method is based on the Fieldprogrammable gate array（FPGA）, which not only retains the advantage using phase synchronization detection technology to overcome the ±1-word counting error, but also accelerates the system response time, simplifies the measurement equipment, and reduces the development cost and power consumption. The experimental results show that the method is reasonable and scientific, and the comparison accuracy of the system can reach the E-12s;level, obviously superior to the measurement accuracy of the traditional frequency standard comparison method,which has a wide application and popularization value.

关键词： Frequency standard comparison Group quantization phase Greatest common factor period Phase group synchronization

Modeling Building Method of Lissajous Figure Reversal Period Based on the Group Quantization Phase Processing

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Chinese Journal of Electronics 2019年第3期28卷 551-558页

作者： DU Baoqiang LI Songlin SUN Xiyan FU Qiang School of Electronic information Engineering Zhengzhou University of Light Industry School of information and Communication Guilin University of Electronic Technology Science and Technology on Electronic information Control Laboratory

To deeply understand the essential relationship between two different-frequency signals and explore the phase synchronization law in frequency standard comparison, a novel modeling building method of Lissajous figure reversal period is proposed based on the group quantization phase processing. The relationships between the Lissajous figure reversal period and group period are revealed. The frequency deviation and nominal frequency of the measured signal are obtained using the group period and number of inflection point in the Lissajous figure. The results of a frequency standard comparison can accurately achieved using the frequency deviation. A lot of noise problems introduced by the frequency divider, frequency multiplier and frequency mixer are solved in the traditional frequency standard comparison, and the high-precision frequency standard comparison results can be quickly obtained using the proposed method. The experimental results show that a close relationship exists among the Lissajous figure reversal period, group period and frequency *** measured frequency can be precisely calculated using the relationship, and the frequency stability of system can reach the E-112/s level.

关键词： Lissajous figure Reversal period Group quantization Frequency stability

A weighted voltage model predictive control method for a virtual synchronous generator with enhanced parameter robustness

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Protection and Control of Modern Power Systems 2021年第1期6卷 482-492页

作者： Leilei Guo Zhiye Xu Nan Jin Yanyan Li Wei Wang College of Electric and information Engineering Zhengzhou University of Light IndustryZhengzhouChina

To address the problem of insufficient system inertia and improve the power quality of grid-connected inverters,and to enhance the stability of the power system,a method to control a virtual synchronous generator(VSG)output voltage based on model predictive control(MPC)is *** of the inductors,capacitors and other components of the VSG can vary as the temperature and current *** the VSG output voltage and power control accuracy using the conventional MPC method may be *** this paper,to improve the parameter robustness of the MPC method,a new weighted predictive capacitor voltage control method is *** detailed theoretical analysis,the principle of the proposed method to reduce the influence of parameter errors on voltage tracking accuracy is ***,the effectiveness and feasibility of the proposed method are verified by experimental tests using the Typhoon control hardware-in-the-loop experimental platform.

关键词： Virtual synchronous generator Model predictive control Optimal voltage vector Parameter error compensation

Research and application of wireless sensor network technology in power transmission and distribution system

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Intelligent and Converged Networks 2020年第2期1卷 199-220页

作者： Jianming Liu Ziyan Zhao Jerry Ji Miaolong Hu “Smart Grid Technology and Equipment”Expert Committee Industry Development and Promotion Center of the Ministry of Industry and Information TechnologyBeijing 100846China State Grid I&T Branch Beijing 100761China Huawei Technologies Co. Ltd.Shenzhen 518129China Wins Wireless Network Technology Co. Ltd.Jiaxing 314036China

Power is an important part of the energy industry,relating to national economy and people’s livelihood,and it is of great significance to ensure the security and stability in operation of power transmission and distribution *** on Wireless Sensor Network technology(WSN)and combined with the monitoring and operating requirements of power transmission and distribution system,this paper puts forward an application system for monitoring,inspection,security,and interactive service of layered power transmission and distribution ***,this paper demonstrates the system verification projects in Wuxi,Jiangsu Province and Lianxiangyuan Community in Beijing,which have been widely used nationwide.

关键词： Wireless Sensor Network(WSN) smart grid power system power transmission power distribution monitoring system

An Urban Traffic Monitoring System Based on the ArcGIS Engine

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International Journal of Plant Engineering and Management 2013年第2期18卷 74-79页

作者： YANG Wei Xi'an Computer Software industry promotion Center

The growing number of vehicles makes traffic jams and accidents significant problems. Making people get to know the real-time road condition can mitigate the effect of congestions greatly, but this is not supported by traditional traffic assistant systems. The intelligent traffic system is born to settle these problems. By making full use of the ArcGIS （Arc Geographic information System） Engine characteristics, this paper designs and imple- ments an urban traffic monitoring system. The main functions of the system include the real-time road condition information display, layer-control, supervisory control management and the basic operations of a map. With the data collected by monitors deployed in intersections, different road conditions are calculated and shown with dif- ferent colors on the map and users can choose suitable roads to get away from the traffic congestion; meanwhile it can offer a reference for a traffic management department to make decisions on traffic control. The system has been deployed and shows high practicability and reliability in practical use.

关键词： ArcGIS Engine traffic control intelligent traffic system road condition display

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Comparative simulation study of effects of eddy-topography interaction in the East/Japan Sea deep circulation

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Acta Oceanologica Sinica 2015年第7期34卷 1-18页

作者： CHOI Youngjin Center for Earth information Science and Technology Japan Agency for Marine-Earth Science and Technology Geo System Research Corporation

In this study the structure and seasonal variations of deep mean circulation in the East/lapan Sea （E/S） were numerically simulated using a mid-resolution ocean general circulation model with two different parameterizations for the eddy-topography interaction （ETI）. The strong deep mean circulations observed in the EIS are well reproduced when using the ETI parameterizations. The seasonal variability in the EIS deep layer is shown by using ETI parameterization based on the potential vorticity approach, while it is not shown in the statistical dynamical parameterization. The driving mechanism of the strong deep mean currents in the E/S are discussed by investigating the effects of model grids and parameterizations. The deep mean circulation is more closely related to the baroclinic process and potential vorticity than it is to the wind driven circulation.

关键词： East/Iapan Sea deep mean current seasonal variability ocean general circulation model eddy- topography interaction

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Growth and Magnetic Properties of Sol-Gel Derived Co-Doped ZnO Thin Film

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Journal of Rare Earths 2006年第Z1期24卷 59-63页

作者： Young Sung Kim Ki Chul Kim Won Pil Tae Dae Ho Yoon Tae Seok Park Su Jeong Suh Advanced Material Process of information Technology Sungkyunkwan University Suwon 440-746 Korea Cambridge-ETRI Joint R&D Centre Electronics and Telecommunications Research Institute Daejeon 305-350 Korea Ulsan Industry Promotion Techno Park Ulsan 683-804 Korea Advanced Material Process of Information Technology Sungkyunkwan University Suwon 440-746 Korea Advanced Material Process of Information Technology Sungkyunkwan University Suwon 440-746 Korea Advanced Material Process of Information Technology Sungkyunkwan University Suwon 440-746 Korea

Zn1-xCoxO films were grown on glass by sol-gel spin coating process. A homogeneous and stable Zn1-xCoxO sol was prepared by dissolving zinc acetate dihydrate, cobalt acetate tetrahydrate and aluminium chloride hexahydrate as solutes in solution of isopropanol and monoethanolamine. The films were postheated and vacuum annealed, and investigated for c-axis preferred orientation and electromagnetic properties. Zn1-xCoxO films with different Co concentrations were oriented well along the c-axis, especially the Zn1-xCoxO film with 10% Co(atom fraction) was highly c-axis oriented. The transmittance spectra show that Zn1-xCoxO films occur d-d transition and sp-d exchange interaction between Co2+ ions. The electrical resistivity of the films at 10% Co had the lowest value because the crystallite size became largest and the crystallinity of the c-axis was improved. X-ray photoelectron spectroscopy and alternating gradient magnetometer analyses indicated that no Co metal cluster was formed, and the ferromagnetism at room temperature appeared. The characteristics of the electrical resistivity and room temperature ferromagnetism of sol-gel derived Zn1-xCoxO films suggest a potential application of dilute magnetic semiconductor devices.

关键词： sol-gel Zn1-xCoxO thin film dilute magnetic semiconductor (DMS)

Coupled CUBIC Congestion Control for MPTCP in Broadband Networks

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Computer Systems Science & Engineering 2023年第4期45卷 99-115页

作者： Jae Yong Lee Byung Chul Kim Youngmi Kwon Kimoon Han Department of information and Communications Engineering Chungnam National UniversityDaejeon34134Korea agency for Defense Development Daejeon34186Korea

Recently,multipath transmission control protocol(MPTCP)was standardized so that data can be transmitted through multiple paths to utilize all available path ***,when high-speed long-distance networks are included in MPTCP paths,the traffic transmission performance of MPTCP is severely deteriorated,especially in case the multiple paths’characteristics are heavily *** order to alleviate this problem,we propose a“Coupled CUBIC congestion control”that adopts TCP CUBIC on a large bandwidth-delay product(BDP)path in a linked increase manner for maintaining fairness with an ordinary TCP traversing the same bottleneck *** verify the performance excellence of the proposed algorithm,we implemented the Coupled CUBIC Congestion Control into Linux kernels by modifying the legacy MPTCP linked-increases algorithm(LIA)congestion control source *** constructed asymmetric heterogeneous network testbeds mixed with large and small BDP paths and compared the performances of LIA and Coupled CUBIC by *** results show that the proposed Coupled CUBIC utilizes almost over 80%of the bandwidth resource in the high BDP path,while the LIA utilizes only less than 20%of the bandwidth for the same *** was confirmed that the resource utilization and traffic transmission performance have been greatly improved by using the proposed Coupled CUBIC in high-speed multipath networks,as well as maintaining MPTCP fairness with competing single-path CUBIC or Reno TCP flows.

关键词： MPTCP congestion control Coupled CUBIC high BDP network