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Field PMU Test and Calibration Method——PartⅡ:Test Signal Identification Methods and Field Test Applications

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 243-253页

作者： sudi Xu Hao Liu Tianshu Bi State Key Lab of Alternate Electric Power System with Renewable Energy Sources(North China Electric Power University) Beijing 102206China State Grid Jangsu Electric Power CO. LTD Research InstituteNanjing 211103China

Synchrophasor measurement units(PMUs)provide synchronized measurement data for wide-area *** improve the effectiveness of synchrophasor-based applications,field PMUs must be tested to ensure their performance and data *** the companion paper(Part I),we proposed a field PMU test and calibration framework consisting of a PMU calibrator and analysis *** I presents the development and test of the PMU *** paper focuses on the analysis center and field test ***,the critical component of the analysis center is the signal identification module,for which the step and oscillation signal identification methods are ***,the performance evaluation criteria of PMU in these two cases are different from *** methods include a step signal detection method based on singular value decomposition(SVD),which has the capability of weak step detection to account for energy leakage of the signal during the step process,and an oscillation signal identification method based on SVD and fast Fourier transform,which can accurately extract oscillation components that benefit from the adaptive threshold setting ***,the analysis center software is implemented based on identification *** integrating the PMU calibrator in Part I with the analysis center in Part II,we can examine in depth the field PMU test applications in three test scenarios,including standard,playback,and field signal *** demonstrate the effectiveness and applicability of the proposed field PMU test methods from both Parts I and II.

关键词： Phasor measurement unit(PMU) field test signal identification oscillation

High-accuracy and Low-complexity Phasor Estimation Method for PMU Calibration

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CSEE Journal of Power and Energy Systems 2021年第6期7卷 1202-1212页

作者： Jinsong Li sudi Xu Hao Liu Tianshu Bi North China Electric Power University and China Electric Power Research Institute Beijing 102206China State Key Lab of Alternate Electric Power System With Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Due to the increasing development of renewables in power systems,the requirements for phasor measurement units(PMUs)becomes higher.A PMU calibrator is an important tool to test and calibrate PMUs to ensure their measurement *** device can provide accurate reference values for error analysis of *** this paper,a phasor algorithm with low computational complexity and high accuracy is proposed for the PMU *** method reduces the processor requirements and development costs of the calibrator,thereby facilitating its *** first,an enhanced discrete Fourier transform(DFT)method is put forward:1)the frequency response of the windowed DFT method is analyzed to reveal its large measurement errors under dynamic conditions;2)the parameter requirements of the DFT window that is regarded as a lowpass filter are analyzed,and thus a lowpass filter with better filtering performance is designed as the window coefficients to improve the estimation ***,based on the enhanced DFT algorithm,a calibrator algorithm framework consisting of two-stage filters and a signal recognition module is *** algorithm can consider the anti-interference ability and dynamic measurement accuracy at a low reporting *** and experimental test results show that the proposed calibrator algorithm provides high-accuracy measurements of the static and dynamic signals with low computational complexity.

关键词： Phasor measurement unit(PMU) PMU calibrator PMU test windowed DFT algorithm

Synchrophasor Measurement Method Based on Cascaded Infinite Impulse Response and Dual Finite Impulse Response Filters

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Journal of Modern Power Systems and Clean Energy 2024年第5期12卷 1345-1356页

作者： Boyu Zhao Hao Liu Tianshu Bi sudi Xu the State Key Laboratory of Alternate Electric Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China the State Grid Jiangsu Electric Power Research Institute Nanjing 210036China

High-precision synchronized measurement data with short measurement latency are required for the applications of phasor measurement units(PMUs).This paper proposes a synchrophasor measurement method based on cascaded infinite impulse response(IIR)and dual finite impulse response(FIR)filters,meeting the M-class and P-class requirements in the IEC/IEEE 60255-118-1 standard.A low-group-delay IIR filter is designed to remove out-of-band interference *** FIR filters with different center frequencies are designed to filter out the fundamental negative frequency component and obtain synchrophasor *** ratio of the amplitudes of the synchrophasor is used to calculate the frequency according to the one-to-one correspondence between the ratio of the amplitude frequency response of the FIR filters and the *** shorten the response time introduced by IIR filter,a step identification and processing method based on the rate of change of frequency(RoCoF)is proposed and *** synchrophasor is accurately compensated based on the frequency and the frequency response of the IIR and FIR filters,achieving high-precision synchrophasor and frequency estimates with short measurement *** and experiment tests demonstrate that the proposed method is superior to existing methods and can provide synchronized measurement data for M-class PMU applications with short measurement latency.

关键词： Synchrophasor measurement frequency estimation infinite impulse response filter complex bandpass filter

Overtraining/Overreaching：Leptin and Ghrelin in Male Recruits

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中国体育科技 2009年第1期45卷 36-38页

作者： Karl sudi Karl-Franzens University Graz Austria

Background In many sports,athletes with low body weight and/or low body fat content have a distinct advantage over their *** an advantage can easily turn into a noticeable disadvantage because low body weight and 'leanness' may also be associated with health *** Athletica(AA) is associated with leanness and thinness in female and male sports athletes despite the fact that these athletes are often very ***-competitive athletes often restrict their caloric intake and/or increase their energy expenditure to maintain a low body mass and/or a low amount of body *** metabolic and endocrine disturbances are often the result of prolonged energy *** disturbances can be detected by alterations in the hormonal profile(low levels of leptin,increased levels of ghrelin) and in changes in body composition.

关键词：运动员体育运动脂肪量体重

Effect of digital elevation models on monitoring slope displacements in open-pit mine by differential interferometry synthetic aperture radar

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1001-1013页

作者： I Nyoman sudi Parwata Shinichiro Nakashima Norikazu Shimizu Takahiro Osawa Graduate School of Science and Engineering Yamaguchi UniversityTokiwadaiUbe755-8611Japan Centre for Research and Application of Satellite Remote Sensing Yamaguchi UniversityTokiwadaiUbe755-8611Japan Regional Satellite Applications Center for Disaster Management(RSCD) Satellite Applications and Operations Center(SAOC)Space Technology DirectorateJapan Aerospace Exploration Agency(JAXA)Industrial Technology InstituteAsutopiaUbe755-0195Japan Centre for Remote Sensing and Ocean Sciences(CreSOS) Udayana UniversityDenpasarBali80232Indonesia

Displacement monitoring in open-pit mines is one of the important tasks for safe management of mining *** interferometric synthetic aperture radar(DInSAR),mounted on an artificial satellite,has the potential to be a cost-effective method for monitoring surface displacements over extensive areas,such as open-pit *** requires the ground surface elevation data in the process of its analysis as a digital elevation model(DEM).However,since the topography of the ground surface in open-pit mines changes largely due to excavations,measurement errors can occur due to insufficient information on the elevation of mining *** this paper,effect of different elevation models on the accuracy of the displacement monitoring results by DInSAR is investigated at a limestone *** addition,validity of the DInSAR results using an appropriate DEM is examined by comparing them with the results obtained by global positioning system(GPS)monitoring conducted for three years at the same limestone *** is found that the uncertainty of DEMs induces large errors in the displacement monitoring results if the baseline length of the satellites between the master and the slave data is longer than a few hundred *** the monitoring results of DInSAR and GPS,the root mean square error(RMSE)of the discrepancy between the two sets of results is less than 10 mm if an appropriate DEM,considering the excavation processes,is *** is proven that DInSAR can be applied for monitoring the displacements of mine slopes with centimeter-level accuracy.

关键词： Open-pit mine Slope monitoring Digital elevation model(DEM) Interferometric synthetic aperture radar (InSAR) Differential interferometric synthetic aperture radar(DInSAR)

Bottom-up fabrication of graphitic carbon nitride nanosheets modified with porphyrin via covalent bonding for photocatalytic H2 evolution

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Nano Research 2019年第12期12卷 3109-3115页

作者： Shufang Tian sudi Chen Xitong Ren Ronghui Cao Haiyan Hu Feng Bai Key Laboratory for Special Functional Materials of Ministry of Education National&Local Joint Engineering Research Center for High-efficiency Display and Lighting TechnologySchool of Material Science and Engineeringand Collaborative Innovation Center of Nano Functional Materials and ApplicationsHenan UniversityKaifeng 475004China

In order to broaden the absorption range of graphitic carbon nitride,one of the common methods is to couple the well-known photosensitizer porphyrin with graphitic carbon nitride through van der Waals weak in *** date,to combine porphyrin with graphitic carbon nitridethrough covalent in teractions has not been *** this work,through rational molecular design,we successfully in corporated porphyrininto the matrixes of graphitic carbon nitride by covale nt bonding via on expot thermal *** resulta nt material not only can wide nthe absorption range but also possess the enlarged specific surface area and construction intramolecular heterojunctions which can contributeto improve electron-holes separation *** resultant photocatalyst exhibited enhanced H2 production rate(7.6 mmol·g^-1·h^-1)and withthe apparent quantum efficiency(AQE)of 13.3%at 450 *** the same time,this method opens a way to fabricate graphitic carb on nitridenano sheets via bottom-up strategy.

关键词： carbon nitride nanosheet porphyrin photocatalytic hydroge nevolution covalent bonding

An efficient visible-light photocatalyst for CO2 reduction fabricated by cobalt porphyrin and graphitic carbon nitride via covalent bonding

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Nano Research 2020年第10期13卷 2665-2672页

作者： Shufang Tian sudi Chen Xitong Ren Yaoqing Hu Haiyan Hu Jiajie Sun Feng Bai Key Laboratory for Special Functional Materials of Ministry of Education National&Local Joint Enginering Research Center for High-efficiency Display and Lighting TechnologySchool of Materials Science and Engineeringand Collaborative Innovation Center of NanoFunctional Materials and ApplicationsHenan UniversityKaifeng 475004China School of Physics and Electronics Henan UniversityKaifeng 475004China

Nanoparticle photosensitizers possess technical advantages for photocatalytic reactions due to enhanced light harvesting and efficient charge *** we report synthesis of semiconductor nanoparticles through covalent coupling and assembly of metalloporphyrin with condensed carbon *** resultant nanoparticles consist of light harvesting component from the condensed carbon nitride and photocatalytic sites from the *** synergetic particle system effectively initiates efficient charge separation and transport and exhibits excellent photocatalytic activity for CO2 *** CO production rate can reach up to 57μmol/(g·h)with a selectivity of 79%over competing H2 *** experiments demonstrate that the combination of light harvesting with photocatalytic activity via covalent assembly is crucial for the high photocatalytic *** to effective charge separation and transfer,the resultant nanoparticle photocatalysts show exceptional photo stability against photo-corrosion under light irradiation,enabling for long-term *** research opens a new way for the development of stable,effective nanoparticle photocatalysts using naturally abundant porphyrin pigments.

关键词： photocatalysis CO2 reduction carbon nitride porphyrin two-dimensional nanosheets function integrated covalent bonding

Porphyrin/Phthalocyanine Decorated BiVO4 for Enhanced Photocatalytic Water Splitting Properties

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Porphyrin/Phthalocyanine Decorated BiVO4 for Enhanced Photoc...

作者： MAHAMMUD SHIRE sudi 江苏大学

学位级别：硕士

水分解成氢和氧的模拟生物光合作用的人工光催化开发是当前众多创新技术之一。半导体钒酸铋（BiVO）因其对可见光的敏感性而被用作类比光合作用的树叶。它对环境无害,制造成本低廉,并且具有相对较低的带隙能量2.4 e V。然而,该物质的带... 详细信息

水分解成氢和氧的模拟生物光合作用的人工光催化开发是当前众多创新技术之一。半导体钒酸铋（BiVO）因其对可见光的敏感性而被用作类比光合作用的树叶。它对环境无害,制造成本低廉,并且具有相对较低的带隙能量2.4 e V。然而,该物质的带隙较宽,导致其PEC水分解效率低,氧气释放过程缓慢,载流子扩散长度短,限制了BiVO的整体光催化能力。因此,本文开发了三种含量丰富的金属复合物（MTPP、TAPC和NiCOP）作为助催化剂用于提高BiVO的光吸收,并研究其协同光催化水分解反应性能。首先,我们研究发现使用具有强大光捕获能力的敏化剂（例如卟啉）修饰半导体材料是一种可行的策略,其可以促进光电解界面处的电子注入和电荷分离效率。本部分工作中,我们制备了三种BiVO/MTPP复合催化剂,它们分别由不同中心金属种类的卟啉（MTPP,M=Ni、Co和Ni）组成。通过一系列光谱技术测试发现BiVO/MTPP复合材料增加了光吸收能力。光电催化性能测试表明,PEC水分解趋势为BiVO/Co TPP>BiVO/NiTPP>BiVO/Cu TPP>BiVO。在AM 1.5G光照射条件下,BiVO的光电流密度在1.23 V ***下从1.01 m A cm提高到了3.9 m A cm。瞬态光电流响应测试确定了样品的电荷注入效率和电荷分离效率,且BiVO/Co TPP在两项测试中表现最优异,分别为80%和65%。采用双层电容(C)对样品的水分解性能研究发现,与BiVO原始电容值150.8μF cm的相比,BiVO/Co TPP的C值显著增大,达到241.3μF cm。本工作为增强型光阳极复合材料提出了一种可能的PEC水分解机制。随后,我们制备了四（氨基）酞菁（TAPC）并将其结合到BiVO表面以形成复合光电阳极BiVO/TAPC。通过SEM发现与原始BiVO相比发现:添加NiCOP后,材料的表面拓扑结构增加。光电测试表明原始BiVO的光电流密度随着TAPC的引入从1.7增加到3.1 m A cm。电化学活性表面积（ECSA）测试进一步证明了这一点,发现BiVO/TAPC的电容值为130μF cm,明显大于BiVO的76μF cm。此外,复合材料的稳定性也优于未修饰的BiVO。该研究表明,使用TAPC作为助催化剂改善了PEC水分解能力,并根据BiVO/TAPC的特性提出了一种合适的机制。最后,我们尝试了BiVO与磷腈基团连接的镍卟啉共价有机聚合物（NiCOP）进行共同催化,以增强BiVO光捕获和PEC水分解能力。所获得的BiVO/NiCOP表现出良好的光捕捉能力,在1.23 V ***下的光电流密度为6.13 m A cm,显著高于相同条件下纯BiVO的光电流密度1.88 m A cm。瞬态光电流响应测试结果表明,施加0.7 V偏置电压时,偏置电压光子电流效率（ABPE）从纯BiVO的0.5%提升到复合材料BiVO/NiCOP的2.4%。电化学阻抗谱（EIS）与光电化学测试结果一致,表明NiCOP层的加入增强了材料的电荷转移动力学并降低了电荷复合速率。

关键词： BiVO4 卟啉共价有机聚合物光电化学水分解助催化剂

Effects of electrostimulation and administration of succinylcholine on the expression of Fos protein in mesencephalic periaqueductal gray matter of rats after simulated weightlessness

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Neural Regeneration Research 2006年第1期1卷 22-25页

作者： Yongjin Zhu sudi Wu Xiaoli Fan Xinai Song Linping Xu Department of Physiology Medical School Xi＇an Jiaotong University Xi＇an 710061 Shaanxi Province China Key Laboratory of Environment and Genes Related to Diseases Xi＇an Jiaotong University Min istry of Education Xi＇an 710061. Shaanxi Province China

BACKGROUND： Expression of Fos in neurons of periaqueductal gray （PAG） is used to reflect the excitability. However, changes of expression of Fos in neurons of PAG are caused by injured electrostimulation after simulated weightlessness, and the relationship between pretreatment and injection of succinylcholine has not been determined yet. OBJECTIVE ： To investigate the changes of expression of Fos in PAG induced by injured electrostimulation pretreatment and injection of succinylcholine at 2 weeks after simulated weightlessness.DESIGN： Observational and controlled animal study.SETTING： Department of Physiology, Medical School, Xi＇an Jiaotong University; Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education. MATERIALS： A total of 24 adult female SD rats, of clean grade and weighing 180-220 g, were selected in this study. METHODS： The experiment was completed in the Experimental Animal Center of Xi＇an Jiaotong University.① All rats were randomly divided into 2 groups according to body mass： simulated weightlessness group and control group with 12 in each group. And then, each group was also divided into 3 subgroups： electrostimulation group, succinylcholine-pretreatment group and succinylcholine-injection group with 4 in each subgroup. ②The model of weightlessness was simulated by tail-suspended female rats, which were described and modified by Cheng Jie. Rats in normal control group were given the same interventions as simulated weightlessness group except for tail-suspended. ③ Experimental method： The rats in electrostimulation group were given nociceptive stimulus by a pair of subcutaneous electrodes inserted into 1 and 5 claw of left hindlimb. The stimulus （current： 10 mA; duration： 1 ms; interval： 1 s） lasted for 30 minutes. The rats in succinylcholine-pretreatment group received stimulus after intravenous administration of succinylcholine, rats in succinylcholine-injection group were not given stimulus, just received succiny

关键词： Fos Effects of electrostimulation and administration of succinylcholine on the expression of Fos protein in mesencephalic periaqueductal gray matter of rats after simulated weightlessness