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IEEE/CAA Journal of Automatica Sinica 2020年第6期7卷 1575-1584页

作者： Tinghua Li Qinghua Yang xiaowei tu Bin Ren School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444China

In this paper,we propose an improved torque sensorless speed control method for electric assisted bicycle,this method considers the coordinate conversion.A low-pass filter is designed in disturbance observer to estimate and compensate the variable disturbance during cycling.A DC motor provides assisted power driving,the assistance method is based on the realtime wheel angular velocity and coordinate system *** effect of observer is proved,and the proposed method guarantees stability under *** is also compared to the existing methods and their performances are illustrated through *** proposed method improves the performance both in rapidity and stability.

关键词： Coordinate conversion disturbance observer electric assisted power inertial measurement unit speed control

Robust Dataset Classification Approach Based on Neighbor Searching and Kernel Fuzzy C-Means

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IEEE/CAA Journal of Automatica Sinica 2015年第3期2卷 235-247页

作者： Li Liu Aolei Yang Wenju Zhou Xiaofeng Zhang Minrui Fei xiaowei tu Shanghai Key Laboratory of Power Station Automation Technology School of Mechatronic Engineering and AutomationShanghai University the School of Computer Science and Electronic Engineering University of Essex the School of Information Science and Electrical Engineering Ludong University

Dataset classification is an essential fundament of computational intelligence in cyber-physical systems (CPS). Due to the complexity of CPS dataset classification and the uncertainty of clustering number, this paper focuses on clarifying the dynamic behavior of acceleration dataset which is achieved from micro electro mechanical systems (MEMS) and complex image segmentation. To reduce the impact of parameters uncertainties with dataset classification, a novel robust dataset classification approach is proposed based on neighbor searching and kernel fuzzy c-means (NSKFCM) methods. Some optimized strategies, including neighbor searching, controlling clustering shape and adaptive distance kernel function, are employed to solve the issues of number of clusters, the stability and consistency of classification, respectively. Numerical experiments finally demonstrate the feasibility and robustness of the proposed method. © 2014 Chinese Association of Automation.

关键词： Artificial intelligence Embedded systems Fuzzy systems Image segmentation MEMS Numerical methods

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《伤寒论》三阳经中风、伤寒浅探

河南中医 2024年第1期44卷 1-4页

作者：陆海鹏王子琴朱颖杨堃涂笑微王楠刘琬琰牛乾海南医学院中医学院海南海口571199

外邪致病,首犯三阳经,发为中风、伤寒,动者属阳为中风,静者属阴为伤寒。太阳中风证为风邪侵袭太阳经所致,病机为风寒袭表,营弱卫强,治疗应调和营卫,解肌祛风,方用桂枝汤加减。太阳伤寒证为素体较强,腠理固密,卫气充盛,风寒犯卫,治疗应... 详细信息

外邪致病,首犯三阳经,发为中风、伤寒,动者属阳为中风,静者属阴为伤寒。太阳中风证为风邪侵袭太阳经所致,病机为风寒袭表,营弱卫强,治疗应调和营卫,解肌祛风,方用桂枝汤加减。太阳伤寒证为素体较强,腠理固密,卫气充盛,风寒犯卫,治疗应辛温发表,宣肺平喘,方用麻黄汤加减。阳明中风证多由太阳中风证转化而来,多表现为太阳阳明合病或两经、三经同时发病,病机复杂,症状多样,张仲景并未设专方,仅告知医者不可妄用下法。阳明伤寒证为寒邪袭表,入里伤及阳明经,阳明经多气多血,外邪本应从热化,又素体胃阳相对不足,故治疗当温中祛湿,不可妄投苦寒泻下之品。少阳中风证属少阳经自发病,少阳经本为阳气蓬勃之经,若阳被郁遏,则会向上伸展,热极火盛,邪火聚集,治疗应和解枢机,方用小柴胡汤类方。少阳伤寒证为少阳经感受寒邪所致,少阳之气郁蒸在表不得散发,治疗应因势利导,和解枢机,不可发汗。中风与伤寒可相互转化,或同时致病,不可将二者机械割裂。

关键词：中风伤寒太阳经病阳明经病少阳经病《伤寒论》张仲景

Numerical simulations of Atlantic meridional overturning circulation(AMOC)from OMIP experiments and its sensitivity to surface forcing

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Journal of Oceanology and Limnology 2024年第2期42卷 454-467页

作者： xiaowei WANG Yongqiang YU State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Atlantic meridional overturning circulation(AMOC)plays an important role in transporting heat meridionally in the Earth’s climate system and is also a key metrical tool to verify oceanic general circulation *** OMIP(Ocean Model Intercomparison Project phase 1 and 2)simulations with LICOM3(version 3 of the LASG/IAP Climate System Ocean Model)developed at the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG),Institute of Atmospheric Physics(IAP),are compared in this *** simulations well reproduce the fundamental characteristics of the AMOC,but the OMIP1 simulation shows a significantly stronger AMOC than the OMIP2 *** the LICOM3 configurations are identical between these two experiments,any differences between them must be attributed to the surface forcing *** analysis suggests that sea surface salinity(SSS)differences should be mainly responsible for the enhanced AMOC in the OMIP1 simulation,but sea surface temperature(SST)also play an unignorable role in modulating *** the North Atlantic,where deep convection occurs,the SSS in OMIP1 is more saline than that in *** find that in the major region of deep convection,the change of SSS has more significant effect on density than the change of *** a result,the SSS was more saline than that in OMIP2,leading to stronger deep convection and subsequently intensify the *** conduct a series of numerical experiments with LICOM3,and the results confirmed that the changes in SSS have more significant effect on the strength of AMOC than the changes in SST.

关键词： oceanic general circulation model(OGCM) Atlantic meridional overturning(AMOC) surface forcing deep convection

Study on damage mechanism and damage distribution of the rear plate under impact of debris cloud

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Defence Technology（防务技术） 2024年第5期35卷 151-167页

作者： Chenyang Wu xiaowei Chen Qiguang He State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyHaidian DistrictBeijing 100081China School of Mechatronical Engineering Beijing Institute of TechnologyHaidian DistrictBeijing 100081China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900SichuanChina

The debris cloud generated by the hypervelocity impact(HVI)of orbiting space debris directly threatens the spacecraft.A full understanding of the damage mechanism of rear plate is useful for the optimal design of protective *** this study,the hypervelocity yaw impact of a cylindrical aluminum projectile on a double-layer aluminum plate is simulated by the FE-SPH adaptive method,and the damage process of the rear plate under the impact of the debris cloud is analyzed based on the debris cloud *** damage process can be divided into the main impact stage of the debris cloud and the structural response of the rear *** main impact stage lasts a short time and is the basis of the rear plate *** the stage of structure response,the continuous deformation and inertial motion of the rear plate dominate the perforation of the rear *** further analyze the damage mechanism and damage distribution characteristics of the rear plate in ***,the connection between velocity space and position space of the debris cloud is established,which promotes the general analysis of the damage law of debris *** on the relationship,the features of typical damage areas are identified by the localized fine *** the cumulative effect and structural response cause the perforation of rear plate;in the non-perforated area,cratering by the impact of hazardous fragments is the main damage mode of the rear plate.

关键词： Damage of rear plate Debris cloud Secondary impact Hypervelocity yaw impact FE-SPH adaptive method

A High Speed Wireless Synchronous Exposure System Based on TDMA

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A High Speed Wireless Synchronous Exposure System Based on T...

第40届中国控制会议

作者： Yehao Wang Qinghua Yang Chuang Wang xiaowei tu School of Mechatronic Engineering and Automation Shanghai University

In a system composed of a line array CCD and multiple LEDs, it is necessary to accurately obtain the CCD exposure sequence and work on the exposure while the LEDs are lit, which makes time synchronization more difficult under wireless conditions. In this paper, a wireless synchronous exposure system based on time division multiple access（TDMA） timing is proposed. The method reduces the network load and hardware power consumption and avoids the use of signal lines for synchronization between nodes. The exposure errors are described, and the errors generation is theoretically analyzed and experimentally verified. The method of node clock synchronization is proposed, and through experiments and data analysis, it is shown that the exposure accuracy reaches 1μs and can operate stably for a long time.

关键词： Synchronous exposure wireless sensor networks line array CCD

Simulation and Frequency Selection of Improved ITS Aviation Channel Model Based on Nakagami-m Function

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Simulation and Frequency Selection of Improved ITS Aviation ...

第40届中国控制会议

作者： Zeng Yuxi xiaowei tu Qinghua Yang Liu Pengyin School of Mechatronic Engineering and Automation Shanghai University

The basic characteristics of ITS（Intelligent Transportation Society of America） aviation channel model are introduced,and an improved ITS aviation channel model based on Nakagami-m distribution function is proposed after analyzing the characteristics of Nakagami-m distribution function in this *** ITS model is applicable to both broadband and narrowband,and it is one of the most widely used and recognized *** method is applicable to the High Frequency（HF）communication range from 2 to 30 *** simulation results show that power delay profile function with minimum error can be simulated by Nakagami-m function,which is one of the key features of ITS ***,a FOT selection system is introduced,which can find the frequency of optimum transmission（less propagation loss,less multipath and less local noise） for both communication parties within 1500 *** finding the minimum echo time delay,we can find the Maximum Usable Frequency（MUF） corresponding to the same echo time delay between the two sides of *** Frequency of Optimum Transmission（FOT） can be found by searching for a nearby local noise minimum around the MUF.

关键词： Nakagami-m distribution function ITS aviation channel model maximum usable frequency FOT selection system

Supervoxel-based Graph Clustering for Accurate Object Segmentation of Indoor Point Clouds

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Supervoxel-based Graph Clustering for Accurate Object Segmen...

第40届中国控制会议

作者： Jingyuan Yu xiaowei tu Qinghua Yang Liyong Liu School of Mechanical Engineering and Automation Shanghai University

The correct segmentation of clustered objects in indoor scenes is a critical step of machine understanding in the field of robotics. However, traditional segmentation methods can hardly meet the requirements of accuracy and real time. To this end, an unsupervised object segmentation method based on supervoxel and graph clustering is proposed in this paper. First, the background is removed based on RANSAC, and the remaining point cloud is over-segmented into supervoxels, which is used to improve the segmentation efficiency and to obtain fully connected graph. Second, a graph clustering method based on pure geometric features is proposed to obtain the corresponding subgraphs of each object using the concavity between ***, a new refinement method for processing the boundaries at the intersection is adapted for obtaining the boundaries with point-level accuracy to improve the segmentation accuracy. The method is experimented on both researcher community public and self-collected datasets. Qualitative and quantitative results show the applicability of our method to robotic real-time object manipulation and its broad development prospect.

关键词： Object Segmentation Point Cloud Supervoxels Graph Clustering

Pitch and Roll Estimation Using Inertial Measurement Unit for Flight Simulator

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Pitch and Roll Estimation Using Inertial Measurement Unit fo...

第40届中国控制会议

作者： Qi Chen Qinghua Yang xiaowei tu Yuxi Zeng School of Mechanical and Electrical Engineering and Automation Shaghai University

The flight simulators are required to measure the pitch and roll in real-time under dynamic *** paper designs a roll and pitch measurement system based on an inertial measurement unit composed of a tri-axis accelerometer and a tri-axis gyroscope and proposes an extended Kalman filter-based attitude（roll and pitch） estimation *** proposed algorithm estimates the external acceleration using a first-order low-pass filtering model and subtracts the estimated external acceleration from the accelerometer *** different tests were conducted depending on the magnitude of the external acceleration to verify the performance of the proposed algorithm under various dynamic ***,three commonly used algorithms,Mahony,Madgwick,and extended Kalman filter,were compared with the proposed *** Root-Mean-Square error of the algorithm is about 1°at higher external acceleration conditions,which is smaller than other algorithms,concluding that the algorithm can obtain a more accurate attitude at high acceleration periods.

关键词： Inertial measurement unit Attitude estimation Kalman filter

Fast Planar Surface Detection in Point Clouds Using Voxel-grid-center-constrained Iterative Adaptive Plane Extraction

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Fast Planar Surface Detection in Point Clouds Using Voxel-gr...

第40届中国控制会议

作者： Liyong Liu xiaowei tu Qinghua Yang Jingyuan Yu School of Mechanical Engineering and Automation Shanghai University

Plane detection is a key pre-processing step in point clouds for many applications, such as buildings registration and automous cars. Many methods have been proposed for plane detection in point clouds, but most of them cannot meet the requirement of speedability. Therefore, in this paper, we propose a voxel-grid-center-constrained iterative adaptive plane extraction method that can meet the speedability without losing the accuracy of the detected planes. First, the point cloud is subdivided using an octree, and then a voxel grid is randomly selected for coplanar testing to find the plane in the point ***, in the plane detection phase, a voxel grid center constraint strategy is used to improve the efficiency of plane ***, an iterative adaptive plane extraction technique is used to improve the robustness. Experimental results demonstrate that the proposed method can achieve high performance on the synthesis datasets as well as on the real datasets.

关键词： plane detection point clouds voxel-grid-center-constrained iterative