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Control of a flexible rotor active magnetic bearing test rig: a characteristic model based all-coefficient adaptive control approach

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Control Theory and Technology 2014年第1期12卷 1-12页

作者： long DI Zongli LIN Charles L. Brown Department of Electrical and Computer Engineering University of VirginiaP.O. Box 400743 Charlottesville VA 22904-4743 U.S.A.

Active magnetic bearings （AMBs） have found a wide range of applications in high-speed rotating machinery industry. The instability and nonlinearity of AMBs make controller designs difficult, and when AMBs are coupled with a flexible rotor, the resulting complex dynamics make the problems of stabilization and disturbance rejection, which are critical for a stable and smooth operation of the rotor AMB system, even more difficult. Proportional-integral-derivative （PID） control dominates the current AMB applications in the field. Even though PID controllers are easy to implement, there are critical performance limitations associated with them that prevent the more advanced applications of AMBs, which usually require stronger robustness and performance offered by modern control methods such as H-infinity control and if-synthesis. However, these advanced control designs rely heavily on the relatively accurate plant models and uncertainty characterizations, which are sometimes difficult to obtain. In this paper, we explore and report on the use of the characteristic model based all-coefficient adaptive control method to stabilize a flexible rotor AMB test rig. In spite of the simple structure of such a characteristic model based all-coefficient adaptive controller, both simulation and experimental results show its strong performance.

关键词： Active magnetic bearings Adaptive control Characteristic modeling Flexible rotor Robustness

Gravitational wave astrophysics, data analysis and multimessenger astronomy

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Science China(Physics,Mechanics & Astronomy) 2015年第12期58卷 44-64页

作者： LEE Hyung Mok LE BIGoT eric-olivier DU ZhiHui LIN ZhangXi GUo XiangYu WEN LinQing PHUKoN Khun Sang PANDEY Vihan BoSE Sukanta FAN Xi-long HENDRY Martin Department of Physics and Astronomy Seoul National University Research Institute of Information Technology Tsinghua National Laboratory for Information Science and TechnologyTsinghua University Laboratoire Astro Particule et Cosmologie (APC) Universit Paris Diderot-Paris 7 Bc/timent Condorcet Case 7020 75205 Paris Cedex 13 France Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and TechnologyTsinghua University School of Physics The University of Western Australia Department of Physics IIT Kanpur Inter-University Centre for Astronomy and Astrophysics Department of Physics & Astronomy Washington State University School of Physics and Electronics Information Hubei University of Education SUPA School of Physics and Astronomy University of Glasgow

This paper reviews gravitational wave sources and their detection. one of the most exciting potential sources of gravitational waves are coalescing binary black hole systems. They can occur on all mass scales and be formed in numerous ways, many of which are not understood. They are generally invisible in electromagnetic waves, and they provide opportunities for deep investigation of Einstein's general theory of relativity. Sect. 1 of this paper considers ways that binary black holes can be created in the universe, and includes the prediction that binary black hole coalescence events are likely to be the first gravitational wave sources to be detected. The next parts of this paper address the detection of chirp waveforms from coalescence events in noisy *** analysis is computationally intensive. Sect. 2 reviews a new and powerful method of signal detection based on the GPUimplemented summed parallel infinite impulse response filters. Such filters are intrinsically real time alorithms, that can be used to rapidly detect and localise signals. Sect. 3 of the paper reviews the use of GPU processors for rapid searching for gravitational wave bursts that can arise from black hole births and coalescences. In sect. 4 the use of GPU processors to enable fast efficient statistical significance testing of gravitational wave event candidates is reviewed. Sect. 5 of this paper addresses the method of multimessenger astronomy where the discovery of electromagnetic counterparts of gravitational wave events can be used to identify sources, understand their nature and obtain much greater science outcomes from each identified event.

关键词： gravitational waves data analysis multimessenger

A review on charging behavior of electric vehicles:data,model,and control

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Control Theory and Technology 2020年第3期18卷 217-230页

作者： Qing-Shan JIA Teng long Center for Intelligent and Networked Systems(CFINS) Department o f AutomationBeijing National Research Center for Information Science and Technology(BNRist)Tsinghua UniversityBeijing 100084China

The adoption and usage of electric vehicles(EVs)have emerged recently due to the increasing concerns on the greenhouse gas issues and energy *** a part of the smart grid,EVs can provide valuable ancillary services beyond consumers of ***,EVs are gradually considered as nonnegligible loads due to their increasing penetration,which may result in negative effects such as voltage deviations,lines saturation,and power *** and interaction among EVs,charging stations,and micro grid have to be considered in the next generation of smart ***,the topic of smart charging has been the focus of many works where a wide range of control methods have been *** one of the bases of simulation,the EV charging behavior and characteristics have also become the focus of many *** this work,we review the charging behavior of EVs from the aspects of data,model,and *** provide the links for most of the data sets reviewed in this work,based on which interested researchers can easily access these data for further investigation.

关键词： Electric vehicle charging behavior data and model

扬子板块西南缘早前寒武纪地质演化:来自撮科元古宙变沉积岩碎屑锆石U-Pb年龄、Hf-o同位素的制约

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岩石学报 2025年第1期41卷 304-320页

作者：高嘉敏谢士稳刘倩王舫陶鹏龙涛中国地质大学(北京)地球科学与资源学院北京100083 中国地质科学院地质研究所北京离子探针中心北京100037 山东省第四地质矿产勘查院潍坊261021

扬子板块的太古宙-古元古代基底出露十分有限,制约了对扬子早前寒武纪地质演化的认识。本次研究对扬子板块西南缘撮科地区的大红山群和昆阳群变沉积岩开展了碎屑锆石原位U-Pb年龄、Hf-o同位素及微量元素研究。测年结果显示,大红山群谐... 详细信息

扬子板块的太古宙-古元古代基底出露十分有限,制约了对扬子早前寒武纪地质演化的认识。本次研究对扬子板块西南缘撮科地区的大红山群和昆阳群变沉积岩开展了碎屑锆石原位U-Pb年龄、Hf-o同位素及微量元素研究。测年结果显示,大红山群谐和锆石年龄分布于3092~1786Ma之间,最年轻碎屑锆石年龄为1786Ma,限定大红山群最大沉积时代为古元古代晚期。昆阳群谐和锆石年龄分布于2874~1031Ma之间,最年轻碎屑锆石年龄为1031Ma,表明昆阳群最大沉积时代为中元古代晚期。除少量较年轻锆石(o同位素特征与撮科古元古代岩浆岩相似,大多数碎屑锆石Hf-o同位素组成与加拿大Rae克拉通古元古代变沉积岩中碎屑锆石相似,暗示古元古代碎屑物质可能仅少部分来自撮科地区已识别的古元古代岩浆岩,而大部分可能来自与Rae克拉通发育的古元古岩浆岩相似的源区。大红山群和昆阳群中1.9~1.03Ga的碎屑锆石可能来自扬子西南缘发育的古元古代晚期-中元古代晚期岩浆岩。结合前人的资料,我们认为我国撮科和越南北部的Phan Si Pan带经历了与加拿大Rae克拉通相似的古元古代演化过程,支持2.4~2.3Ga扬子西南缘卷入Arrowsmith造山事件,并与Rae克拉通一起参与哥伦比亚超大陆聚合过程的认识。

关键词：扬子西南缘撮科地区哥伦比亚超大陆大红山群和昆阳群碎屑锆石

Removal of sulfonamide antibiotics from wastewater by gamma irradiation in presence of iron ions

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Nuclear Science and Techniques 2016年第5期27卷 104-108页

作者： Zhong Wan Jian-long Wang Collaborative Innovation Center for Advanced Nuclear Energy Technology INET Tsinghua UniversityBeijing 100084 China Beijing Key Laboratory of Radioactive Waste Treatment INET Tsinghua University Beijing 100084 China

The presence of sulfonamide antibiotics in aquatic environments has received increasing attention in recent ***(SD),a widely used heterocyclic sulfonamide pharmaceutical,has entered into the receiving water *** this paper,gamma rays are used to irradiate samples of sulfadiazine antibiotics-containing *** results demonstrate that SD can be effectively degraded by irradiation,but the mineralization degree of SD(in terms of ToC) is not as efficient as the SD *** addition of Fe^(2+) can significantly enhance the SD degradation and mineralization through the generation of hydroxyl radical by catalytic decomposition of H_2o_2 from water *** chromatography analysis indicates that sulfate ions(So_4^(2-)) and formate(HCoo^-) are the main intermediate *** irradiation is a promising technology for removing low-concentration antibiotics from water and wastewater.

关键词： γ射线照射废水样品抗生素磺胺类铁离子降解效率离子色谱分析羟基自由基

optimization of conditions for preparation of ZSM-5@silicalite-1 core–shell catalysts via hydrothermal synthesis

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2070-2076页

作者： Chuang Liu Yihua long Zhengbao Wang Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological Engineering Zhejiang University

Although the preparation of ZSM-5@silicalite-1(ZS) core–shell catalysts has been reported in the literature,their selectivity to para-xylene(PX)in the toluene alkylation with methanol is difficult to *** we present the effects of water and ZSM-5 adding amounts in the synthesis solution,the hydrothermal synthesis time,and the Si/Al ratio of core ZSM-5 on the catalytic performance of ZS core–shell *** ZS core–shell catalysts were characterized by X-ray diffraction (XRD),N_2 adsorption,and NH_3 temperature-programmed desorption (NH_3-TPD) *** highest PX selectivity of 95.5%was obtained for the ZS(Si/Al=140) catalyst prepared in the synthesis solution with a molar ratio of 0.2 TPAoH:1TEoS:250H_2o at 175°C and 10 r·min^(-1) for only 2 h and the corresponding toluene conversion is as high as 22.8% for the alkylation of toluene with methanol.

关键词： ZSM-5 Silicalite-1 Core–shell catalyst Alkylation Para-selectivity

Effects of relative humidity on the characterization of a photochemical smog chamber

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Journal of Environmental Sciences 2011年第12期23卷 2013-2018页

作者： Gaoshuo Hu Yongfu Xu long Jia State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Water vapor plays an important role in many atmospheric chemical reactions. A self-made indoor environmental smog chamber was used to investigate the effects of relative humidity （RH） on its characterization, which included the wall effects of reactive species such as o3 and Nox, and the determination of chamber-dependent oH radicals in terms of Co-Nox irradiation experiments. Results showed that the rate constant of o3 wall losses increased with increasing RH, and that their relationship was linearly significant. Although RH aflected the rate constant of Nox wall losses, their relationship was not statistically significant. Background air generated a small amount of ozone at both high and low RH. When RH varied from 5% to 79%, the apparent rate constant kNo2→HoNo for the conversion of No2 into gas phase HoNo was estimated in the range of 0.70×10-3–2.5×10-3 min-1. A linear relationship between kNo2→HoNo and RH was obtained as kNo2→HoNo （10-3 min-1） = –0.0255RH ＋ 2.64, with R2 and P value being 0.978 and 0.01. To our knowledge, this is the first report on their relationship. The generation mechanism for HoNo and oH was also discussed in this work.

关键词： chamber characterization relative humidity wall effects oH radicals

Rapid and chemoselective imidation of sulfides in aqueous buffer enabled by a novel guanidine-derived N-o reagent

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Science China Chemistry 2024年第6期67卷 1929-1934页

作者： Hanzheng Li long Xu Jiajia Dong Key Laboratory of organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032China Institute of Translational Medicine National Facility for Translational Medicine(Shanghai)Shanghai Jiao Tong UniversityShanghai200240China School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai200240China Shanghai Artificial Intelligence Laboratory Shanghai200232China

Herein we report the facile synthesis of a series of novel N-o reagents and identify N′-di-Boc-N′′-[(mesitylsulfonyl)oxy]-guanidine as an efficient imidating *** reagent is synthetically scalable and bench-stable,yet it shows unprecedented reactivity and chemoselectivity towards S(II)in buffer/hexafluoroisopropanol(HFIP)system,to generate a new class of Nguanyl *** transformation of N-guanyl sulfilimines to N-guanyl sulfoximines provides us a chance to investigate these rarely reached compounds,which are shown to be versatile precursors to a variety of N-heterocyclic and *** work provides an addition to the tool box of both sulfur imidation and guanidine synthesis,especially for the need of rapid and selective modifications of sulfur(II)center under biocompatible conditions.

关键词： sulfur imidation N-o reagent

CoNVERGENCE oF INNER ITERATIoNS SCHEME oF THEDISCRETE oRDINATE METHoD IN SPHericAL GEoMETRY

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Journal of Computational Mathematics 2005年第3期23卷 321-326页

作者： Zhi-junShen Guang-weiYuan long-junShen LaboratoryofComputationalPhysics InstituteofAppliedPhysicsandComputationalMathematicsP.O.Box8009Beijing100088China

In transport theory, the convergence of the inner iteration scheme to the spherical neutron transport equation has been an open problem. In this paper, the inner iteration for a positive step function scheme is consid... 详细信息

关键词： transport equation discrete ordinate inner iteration