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Research on the Rectifier Control Method in Drive System 25th

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Research on the Rectifier Control Method in Drive System

第25届中国控制与决策会议

作者： WANG Xiao-yu QIAN Xiao-long Harbin Electric Machinery company limited Key Laboratory of Process Industry Automation of MOE Northeastern University

ISBN: (纸本)9781467355339

The selection of oriented vector control method for three-level PWM rectifier is an important factor for getting stable DC voltage. Because the observer has an uncertain initial value, and the rectifier has a large start-up current which may lead to the system failure, while using the virtual flux oriented vector control method for three-level PWM rectifier. For this reason, the grid voltage oriented vector control strategy was adopted to achieve a more effective control on the rectifier. However, the complex mathematical model of this method makes the controller designed difficultly. As the neutral point voltage balance of three-level rectifier can get a good control effect throughout the entire control process, the average current of the neutral point was regarded as zero. Besides, transforming symmetric three-phase parameter to constant DC parameter through appropriate coordinates transform can change the three-phase nonlinear system with time-variable issue into two-phase linear system, and the rational simplification of rectifier model was presented according to the project requirement, which has laid a foundation for the design of controller so as to make it easy for the selection of the PID controller parameters. At last, an effective control on the DC bus voltage and the grid power factor was achieved.

关键词： Three-level PWM Rectifier Oriented Vector Control Power Factor Rational Simplification

Artificial intelligence improves accuracy, efficiency, and reliability of a handheld infrared eccentric autorefractor for adult refractometry

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International Journal of Ophthalmology(English edition) 2022年第4期15卷 628-634页

作者： Yi-Ting Cao Dan-Yang Che Yi-Lei Pan Yun-Li Lu Chong-Yang Wang Xiao-Li Zhang Yun-Fei Yang Ke-Ke Zhao Ji-Bo Zhou Department of Ophthalmology Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology Shanghai 200011China Shanghai MediWorks Precision Instruments company limited Shanghai 201112China Department of Ophthalmology Shanghai Children’s Medical CenterShanghai Jiao Tong University School of MedicineShanghai 200127China

AIM: To evaluate the accuracy, efficiency, and reliability of a handheld infrared eccentric autorefractor(h ICA) with artificial intelligence(AI) by comparing its refraction measurements to those recorded using h ICA and a clinical table-mounted automatic refractor(TAR).METHODS: A cross-sectional study using three optometers, including h ICA with or without AI and TAR, for refractometry of adults(aged 19-49 years old) with no signs of ocular disease or trauma in the absence of cycloplegia. Right and left eye refraction data were recorded, including the spherical equivalent(SE), diopter of spherical power(DS), diopter of cylindrical power(DC) decomposed into vectors J0 and J45, and measurement times. To avoid analytical difficulties associated with the interdependence of observations between eyes from the same individual, the Generalized Estimation Equation was used to compare the SE, DS, J0 and J45 measurements, and the times thereof, among the different groups. The intraclass correlation coef f icient(ICC) and Spearman’s rank correlation coefficient were used to evaluate correlations among the measurements recorded by the three different instruments. Bland-Altman were used to analyze the precision of the equipment by the agreement. RESULTS: A total of 70 patients(140 eyes;mean age: 31.37 y;range: 19-49 y) were assessed using refractometry. In a brightly lit environment, there was no significant difference between the mean SE recorded using TAR and that recorded using h ICA with AI or without AI(both P>0.05). In an intense-light environment, h ICA equipped with AI showed a better detection rate than without AI. Light intensity had a greater effect on dioptric measurements recorded using h ICA without AI(P<0.001) than on those recorded using the one equipped with AI(P<0.05). Measurement times varied significantly between the different light intensities and instruments(P<0.05).CONCLUSION: For the normal human eyes, AI may improve the accuracy, efficiency, and reliabil

关键词： dioptric measurement artificial intelligence equipment design infrared eccentric autorefractor

Draft Genome of White-blotched River Stingray Provides Novel Clues for Niche Adaptation and Skeleton Formation

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Genomics, Proteomics & Bioinformatics 2023年第3期21卷 501-514页

作者： Jingqi Zhou Ake Liu Funan He Yunbin Zhang Libing Shen Jun Yu Xiang Zhang School of Public Health Shanghai Jiao Tong University School of MedicineShanghai 200025China Department of Life Sciences Changzhi UniversityChangzhi 046011China Greehey Children’s Cancer Research Institute UT Health San AntonioSan AntonioTX 78229USA State Key Laboratory of Cell Biology Shanghai Key Laboratory of Molecular AndrologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai 200031China International Human Phenome Institutes(Shanghai) Shanghai 200433China Institute of Neuroscience Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China Beijing Institute of Genomics Chinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Shanghai Nanmulin Biotechnology company limited Shanghai 200031China

The white-blotched river stingray(Potamotrygon leopoldi)is a cartilaginous fish native to the Xingu River,a tributary of the Amazon River *** a rare freshwater-dwelling cartilaginous fish in the Potamotrygonidae family in which no member has the genome sequencing information available,*** provides the evolutionary details in fish phylogeny,niche adaptation,and skeleton *** this study,we present its draft genome of 4.11 Gb comprising 16,227 contigs and 13,238 scaffolds,with contig N50 of 3937 kb and scaffold N50 of 5675 kb in *** analysis shows that *** is a slow-evolving fish that diverged from elephant sharks about 96 million years ***,two gene families related to the immune system(immunoglobulin heavy constant delta genes and T-cell receptor alpha/delta variable genes)exhibit expansion in *** *** also identified the Hox gene clusters in *** and discovered that seven Hox genes shared by five representative fish species are missing in *** RNA sequencing data from *** and other three fish species demonstrate that fishes have a more diversified tissue expression spectrum when compared to *** functional studies suggest that lack of the gc gene encoding vitamin D-binding protein in cartilaginous fishes(both *** and Callorhinchus milii)could partly explain the absence of hard bone in their ***,this genome resource provides new insights into the niche adaptation,body plan,and skeleton formation of ***,as well as the genome evolution in cartilaginous fishes.

关键词： White-blotched river stingray Potamotrygon leopoldi De novo genome assembly Vitamin D-binding protein Niche adaptation

Robust containment control for a class of heterogeneous uncertain nonlinear multi-agent systems in lower triangular form

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Journal of Control and Decision 2021年第3期8卷 269-279页

作者： Jing Zhao Shibin Shen Fei Xie Yanfei Sun Fengyu Xu College of Automation&College of Artificial intelligence Nanjing University of Posts and TelecommunicationsNanjingPeople’s Republic of China School of Electrical and Automation Engineering Nanjing Normal UniversityNanjingPeople’s Republic of China Jiangsu Engineering Laboratory for Internet of Things and Intelligent Robotics Nanjing University of Post and TelecommunicationsNanjingPeople’s Republic of China Nanjing Institute of Intelligent High-End Equipment Industry limited company NanjingPeople’s Republic of China

This paper studies the robust containment control problem for a class of nonlinear multi-agent systems in lower triangular form with parameter *** agents are heterogenous with the particularity that the dynamics of the leaders are totally different from those of the *** interconnection topology is described by a general directed *** on the distributed internal model,the robust containment control problem is first converted into the stabilisation problem for an augmented network.A distributed state feedback control is then proposed to solve the stabilisation problem of the subsequent augmented network by the block backstepping *** the proposed control,all the followers’outputs will converge to the convex hull spanned by the leaders.

关键词： Containment nonlinearmultiagentsystems heterogeneous uncertainparameter internal model

Coarse-to-fine visual autonomous unmanned aerial vehicle landing on a moving platform

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Biomimetic intelligence & Robotics 2023年第1期3卷 65-73页

作者： Qiangqiang Cui Min Liu Xiaoyin Huang Ming Gao IKingtec Intelligent Technology Co. LtdBeijing 100089China State Grid Jibei Electric Power company limited Beijing 100032China State Grid Jibei Electric Power Co. Ltd.Beijing EHV Power Transmission CompanyBeijing 102488China

Autonomous unmanned aerial vehicle(UAV)landing is a challenging task,especially on a moving platform in an unstructured *** such a scenario,successful UAV landing is mainly affected by poor UAV localization *** solve this problem,we propose a coarse-to-fine visual autonomous UAV landing system based on an enhanced visual positioning *** landing platform is marked with a specially designed QR code marker,which is developed to improve the landing accuracy when the UAV approaches the landing ***,we employ the you only look once framework to enhance the visual positioning accuracy,thereby promoting the landing platform detection when the UAV is flying far *** framework recognizes the QR code and decodes the position of a UAV by the corner points of the QR ***,we use the Kalman filter to fuse the position data decoded from the QR code with those from the inertia measurement unit ***,the position data are used for UAV landing with a developed hierarchical landing *** verify the effectiveness of the proposed system,we performed experiments in different environments under various light *** experimental results demonstrate that the proposed system can achieve UAV landing with high accuracy,strong adaptability,and *** addition,it can achieve accurate landing in different operating environments without external real-time kinematic global positioning system(RTK-GPS)signals,and the average landing error is 11.5 cm,which is similar to the landing error when using RTK-GPS signals as the ground truth.

关键词： UAV Accurate landing QR code detection YOLOv5 m PnP solver

Nonlinear Aeroelastic Responses of an Airfoil with a Control Surface by Precise Integration Method

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Nonlinear Aeroelastic Responses of an Airfoil with a Control...

作者： Xiwen Huang Suxin Xie Yunping Zhang Yanmao Chen Department of Mechanics Sun Yat-sen University Basic Course Teaching Department Jiangxi Industry Polytechnic College Nari Technology Development limited company

This paper presents a highly accurate algorithm,based on precise integration method（PIM）,to investigate the aeroelastic system of an airfoil with control *** nonlinear system is separated as linear sub-systems,which are solved by PIM *** each step,a predictor-corrector algorithm is proposed to detect switching points between *** examples show that,the presented algorithm is much more accurate and efficient than the widely-used Runge-Kutta ***,the Runge-Kutta method even provides false *** such high precision and efficiency,the presented algorithm has the potential to become a benchmark for comparison in solving piecewise-smooth dynamical systems.

关键词： Airfoil Control surface Piecewise Aeroelastic Precise integration method

Prediction of oil flow rate through an orifice flow meter: Artificial intelligence alternatives compared

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Petroleum 2020年第4期6卷 404-414页

作者： Hamzeh Ghorbani David A.Wood Abouzar Choubineh Afshin Tatar Pejman Ghazaeipour Abarghoyi Mohammad Madani Nima Mohamadian Young Researchers and Elite Club Ahvaz BranchIslamic Azad UniversityAhvazIran DWA Energy limited LincolnUnited Kingdom Petroleum Department Petroleum University of TechnologyAhwazIran Young Researchers and Elite Club North Tehran BranchIslamic Azad UniversityTehranIran National Iranian South Oil company(NISOC) AhvazIran Young Researchers and Elite Club Omidiyeh BranchIslamic Azad UniversityOmidiyehIran

Fluid-flow measurements of petroleum can be performed using a variety of equipment such as orifice meters and wellhead *** is useful to understand the relationship between flow rate through orifice meters(Qv)and the five fluid-flow influencing input variables:pressure(P),temperature(T),viscosity(μ),square root of differential pressure(ΔP^0.5),and oil specific gravity(SG).Here we evaluate these relationships using a range of machine-learning algorithms applied to orifice meter data from a pipeline flowing from the Cheshmeh Khosh Iranian oil *** coefficients indicate that(Qv)has weak to moderate positive correlations with T,P,andμ,a strong positive correlation with theΔP^0.5,and a weak negative correlation with oil specific *** order to predict the flow rate with reliable accuracy,five machine-learning algorithms are applied to a dataset of 1037 data records(830 used for algorithm training;207 used for testing)with the full input variable values for the data set *** algorithms evaluated are:Adaptive Neuro Fuzzy Inference System(ANFIS),Least Squares Support Vector Machine(LSSVM),Radial Basis Function(RBF),Multilayer Perceptron(MLP),and Gene expression programming(GEP).The prediction performance analysis reveals that all of the applied methods provide predictions at acceptable levels of *** MLP algorithm achieves the most accurate predictions of orifice meter flow rates for the dataset *** and RBF also achieve high levels of *** and LSSVM perform less well,particularly in the lower flow rate range(i.e.,<40,000 stb/day).Some machine learning algorithms have the potential to overcome the limitations of idealized streamline analysis applying the Bernoulli equation when predicting flow rate across an orifice meter,particularly at low flow rates and in turbulent flow *** studies on additional datasets are required to confirm this.

关键词： Orifice flow meters Flow-rate-predicting virtual meters Multiple machine-learning algorithm comparisons Metrics influencing oil flow Flow-rate prediction error analysis

A GA-Based Global Decision Support System for Garment Production

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A GA-Based Global Decision Support System for Garment Produc...

2005 International Conference on Neural Networks and Brain(ICNN&B’05)

作者： Rong-Chang Chen Shiue-Shiun Li Chih-Chang Lin Chen-Chang Feng Department of Logistics Engineering and Management Graduate Institute of Business Administration Graduate Institute of Computer Science and Information Technology National Taichung Institute of Technology Director of Information Center Eclat Textile company limited No.28 Wu-Chuan Rd.Wu-Ku Industrial ParkTaipei

＜正＞It is hard to make decisions with a human’s brain alone,especially in global *** improving technology, each industry has to face the problem "How can I get the lower cost in the global markets?" and solve the *** this study,we try to develop a decision support system for garment industry because the garment industry operates on low profits and can’t bear too much cost. The system includes three major parts,i.e.,an input database,an analytical tool,and presentation *** information in the data is real data provided by a garment corporation and is collected from the Enterprise Resource Planning（ERP） *** tool for analyzing in this study is genetic algorithm（GA）.Finally,visualized charts and reports are used to show the scheduling result to decision *** system is designed to be easy to use and suitable to the garment industry.

关键词： Decision support systems Production systems Clothing industry Costs Enterprise resource planning Globalization Visual databases Data analysis Algorithm design and analysis Genetic algorithms