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TWO-DEGREE-OF-FREEDOM ROBUST CONTROL WITH APPLICANTION IN THE NON-CIRCULAR TURNING

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TWO-DEGREE-OF-FREEDOM ROBUST CONTROL WITH APPLICANTION IN TH...

ROBUST COMPOSITE CONTROLLER DESIGN FOR HIGH-ACCURACY POSITIONING SYSTEM

2006年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： liu hongbin, hu dejin School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, China

A method combining zero phase error tracking based feed forward control with two-degrees-of-freedom H∞ robust control is proposed for the linearization control of piezoelectric translator (PZT) and us

关键词： Zero phase error tracking H∞ robust control imprecise model two-degrees-of-freedom controller.

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ROBUST COMPOSITE CONTROLLER DESIGN FOR HIGH-ACCURACY POSITIO...

基于GEE的合肥市土地利用/覆盖类型变化研究

2006年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： liu hongbin, hu dejin School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, China

The control method for Industrial process is used for the piezoelectric translator (PZT) actuator by equivalent transformation of the model. A new self-tuning approach of IMC based PID control algorit

关键词： Internal model control (IMC) control, feedforward control noncircular machining, integral square error (ISE) optimum control.

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测绘工程 2025年第2期34卷 38-47页

作者：王德金刘春阳安徽理工大学空间信息与测绘工程学院安徽淮南232001 安徽理工大学矿山采动灾害空天地协同监测与预警安徽普通高校重点实验室安徽淮南232001

依赖本地单机状态下的传统处理方式通常难以应对大尺度和长时序的遥感影像处理需求,文中研究以合肥市为例,提出一种基于谷歌地球引擎(GEE)平台,使用已有的土地利用/覆盖分类数据集快速选取可用于逐年影像分类训练样本的方法;然后对合肥... 详细信息

依赖本地单机状态下的传统处理方式通常难以应对大尺度和长时序的遥感影像处理需求,文中研究以合肥市为例,提出一种基于谷歌地球引擎(GEE)平台,使用已有的土地利用/覆盖分类数据集快速选取可用于逐年影像分类训练样本的方法;然后对合肥市2013—2022年Landsat影像数据进行无云筛选和影像拼接等操作,得到年度影像分类底图;再通过融合光谱波段、光谱指数、地形特征、夜间灯光指数4个维度构建14个分类特征,采用随机森林模型的方法,对合肥市土地利用/覆盖类型变化进行研究分析,结果表明:①使用已有的土地利用/覆盖数据集获取训练样本的方法具有可行性,样本点选取精度高于95.2%。②融合多维度遥感特征的随机森林模型影像分类方法能准确地提取土地利用/覆盖分类信息,4个时间段的平均总体精度OA为92.75%,Kappa系数为0.905。③研究期间内,耕地是主要的转出源,其主要转化为建设用地,建设用地面积1931.01 km^(2)增加到3360.88 km^(2),耕地面积7386.86 km^(2)减少到6029.48 km^(2),水体面积1210.88 km^(2)减少到1105.98 km^(2),林地和未利用地面积总体未发生明显变化。文中研究为合肥市逐年土地利用/覆盖分类提供方法,同时为土地资源管理、生态可持续发展等领域提供数据支撑。

关键词：长时序土地利用/覆盖变化时空特征分析

STUDY ON SINGULAR CONFIGURATIONS AND COMPUTER SIMULATION OF 6R ROBOT

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 177-180页

作者： Zhang Kai hu dejin liu Chengliang School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200030, China School of Mechanical Engineering Shanghai Jiaotong University 上海 200030

When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe approximate velocity of joint near singular configuration point by adding damped vector isproposed and a modified algorithm is provided. With the analysis of J^(-1) the singularconfigurations of 6R robot are divided into structure boundary singularity , boundary singularity ,inner singularity and wrist singularity. The conditions of singularities of the robot have beenascertained. The computer simulations of the singularities of the robot are developed, which havemany advantages over previous description methods of the singular configurations of robot. With thehelp of boundary singularity analysis, a application in welding trajectory planning checking of therobot has been carried out and the simulation result proved visualized and useful.

关键词： Robot Singular configuration Computer simulation

Shape selective catalysis in methylation of toluene： Development, challenges and perspectives

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 103-112页

作者： Jian Zhou Zhicheng liu Yangdong Wang dejin Kong Zaiku Xie Shanghai Research Institute of Petrochemical Technology S/NOPEC Shanghai 201208 China SINOPEC Beijing 100027 China

Toluene methylation with methanol offers an alternative method to produce p-xylene by gathering methyl group directly from C1 chemical sources. It supplies a ＂molecular engineering＂ process to realize directional conversion of toluene/methanol molecules by selective catalysis in complicated methylation system. In this review, we introduce the synthesis method ofp-xylene, the development history of methylation catalysts and reaction mechanism, and the effect of reaction condition in para-selective technical process. If constructing p-xylene as the single target product, the major challenge to develop para-selective toluene methylation is to improve the p-xylene selectivity without, or as little as possible, losing the fraction of methanol for methylation. To reach higher yield ofp-xylene and more methanol usage in methylation, zeolite catalyst design should consider improving mass transfer and afterwards coveting external acid sites by surface modification to get short ＂micro-tunnels＂ with shape selectivity. A solid understanding of mass transfer will benefit realizing the aim of converting more methanol feedstock into para-methyl group.

关键词： shape selective catalysis methylation of toluene

Genesis of the Changba–Lijiagou Giant Pb-Zn Deposit, West Qinling, Central China: Constraints from S-Pb-C-O isotopes

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Acta Geologica Sinica(English Edition) 2020年第4期94卷 884-900页

作者： WEI Ran WANG Yitian MAO Jingwen hu Qiaoqing QIN Siting liu Shengyou YE dejin YUAN Qunhu DOU Ping School of Earth Science and Resources Chang'an UniversityXi'an 710064China MNR Key Laboratory of Metallogeny and Mineral Resource Assessment Institute of Mineral ResourcesChina Academy of Geological SciencesBeijing 100037China Geological Survey of Gansu Province Lanzhou 730030China Changba Pb-Zn Mine of Baiyin Nonferrous Metals Company ChengxianGansu 742500China

The extensive Changba-Lijiagou Pb-Zn deposit is located in the north of the Xihe–Chengxian ore cluster in West Qinling. The ore bodies are mainly hosted in the marble, dolomitic marble and biotite-calcite-quartz schist of the Middle Devonian Anjiacha Formation, and are structurally controlled by the fault and anticline. The ore-forming process can be divided into three main stages, based on field geological features and mineral assemblages. The mineral assemblages of hydrothermal stage I are pale-yellow coarse grain, low Fe sphalerite, pyrite with pits, barite and biotite. The mineral assemblages of hydrothermal stage II are black-brown cryptocrystalline, high Fe shalerite, pyrite without pits, marcasite or arsenopyrite replace the pyrite with pits, K-feldspar. The features of hydrothermal stage III are calcite-quartz-sulfide vein cutting the laminated, banded ore body. Forty-two sulfur isotope analyses, twenty-five lead isotope analyses and nineteen carbon and oxygen isotope analyses were determined on sphalerite, pyrite, galena and calcite. The δ34 S values of stage I(20.3 to 29.0‰) are consistent with the δ34 S of sulfate(barite) in the stratum. Combined with geological feature, inclusion characteristics and EPMA data, we propose that TSR has played a key role in the formation of the sulfides in stage I. The δ34 S values of stage II sphalerite and pyrite(15.1 to 23.0‰) are between sulfides in the host rock, magmatic sulfur and the sulfate(barite) in the stratum. This result suggests that multiple S reservoirs were the sources for S2-in stage II. The δ34 S values of stage III(13.1 to 22‰) combined with the structure of the geological and mineral features suggest a magmatic hydrothermal origin of the mineralization. The lead isotope compositions of the sulfides have 206 Pb/204 Pb ranging from 17.9480 to 17.9782, 207 Pb/204 Pb ranging from 15.611 to 15.622, and 208 Pb/204 Pb ranging from 38.1368 to 38.1691 in the three ore-forming stages. The narrow and symmetric di

关键词： S-Pb isotopes C-O isotopes Pb-Zn deposit ore genesis epigenetic hydrothermal Changba–Lijiagou West Qinling

The Oblique Alfvén Ion Beam Instability in the Earth’s Ion Foreshock

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Research in Astronomy and Astrophysics 2023年第2期23卷 177-186页

作者： Yuhang Yao Jinsong Zhao huasheng Xie Wen liu dejin Wu Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Hebei Key Laboratory of Compact Fusion Langfang 065001China ENN Science and Technology Development Co. Ltd.Langfang065001China

How ions evolve in the Earth’s ion foreshock is a basic problem in the heliosphere community,and the ion beam instability is usually proposed to be one major mechanism affecting the ion dynamics *** work will perform comprehensive analyses of the oblique ion beam instability in the Earth’s ion *** show that in addition to two well-known parallel instabilities (i.e.,the parallel fast-magnetosonic whistler instability and the parallel Alfvén ion cyclotron instability),the oblique Alfvén ion beam (OA/IB) instability can also be triggered by free energy relating to the relative drift d V between the solar wind proton and reflected proton *** slow d V (e.g.,d V■2.2V_(A),where VAdenotes the Alfvén speed),it only triggers the OA/IB *** d V■2.2V_(A),the growth rate in the OA/IB instability can be about 0.6 times the maximum growth rate in parallel ***,this work finds the existence of two types of OA/IB *** first one appears at slow d V and in the small wavenumber region at fast d V,and this instability can be described by the cold fluid *** second one arises in large wavenumber regions at fast d V,and this instability only appears in warm ***,through the energy transfer rate method,we propose that the OA/IB instability is driven by the competition among the Landau and cyclotron wave-particle interactions of beam protons,the cyclotron wave-particle interaction of core protons,and the Landau wave-particle interaction of *** oblique waves can experience significant damping,the importance of the OA/IB instability may be the effective heating of ions in the Earth’s foreshock.

关键词： plasmas-instabilities-waves-(Sun:)solar-terrestrial relations

MMSE channel estimation for two-port demodulation reference signals in new radio

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Science China(Information Sciences) 2021年第6期64卷 247-248页

作者： dejin KONG Xiang-Gen XIA Pei liu Qibiao Zhu School of Electronic and Electrical Engineering Wuhan Textile University Department of Electrical and Computer Engineering University of Delaware School of Information Engineering Wuhan University of Technology School of Information Engineering Nanchang University

Dear editor,Orthogonal frequency division multiplexing(OFDM) has been adopted in new radio(NR) [1], and multiple-port demodulation reference signal(DMRS) has been designed to achieve channel estimation. In NR, two ports of DMRS share the same frequency resource elements(RE) by employing an orthogonal code comprising cyclic shift phase. In general, channel estimation can be achieved via the classical discrete Fourier transform(DFT) scheme [2, 3] as channels for the two ports of DMRS can be separated in the time domain via the DFT scheme.

关键词： MMSE channel estimation for two-port demodulation reference signals in new radio

Applications of flexible electrochemical electrodes in wastewater treatment:A review

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Chinese Chemical Letters 2024年第8期35卷 84-92页

作者： Jiqing liu Qi Dang Liting Wang dejin Wang Liang Tang Key Laboratory of Organic Compound Pollution Control Engineering(MOE) School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444China School of Resources and Environment Anqing Normal UniversityAnqing 246011China

The advancement of energy storage technology has paved the way for the application of electrochemi-cal processes in achieving low-carbon and precise environmental pollution *** play a crucial role in efficiently removing organic pollutants and heavy *** implement electrochemical pollution control technology in practical engineering,flexible electrode preparation is *** review highlights recent progress in flexible electrode research,focusing on the selection and structural design of flexible electrode *** summarizes the latest advancements in current collectors,active mate-rials,and preparation methods to enhance conductivity,flexibility,and cycle *** application of flexible electrodes in water pollution control is categorized into three aspects:Organic pollutants,inor-ganic pollutants,and composite ***,the challenges and research requirements for enhanc-ing electrode flexibility in environmental governance are discussed,along with prospects for their future applications.

关键词： Flexible electrode Wastewater treatment Photoanode Removal effect Emerging contaminants