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Error aware multiple vertical planes based visual localization for mobile robots in urban environments

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Science China(Information Sciences) 2015年第3期58卷 159-172页

作者： LI HaiFeng wang hongpeng LIU JingTai College of Computer Science and Technology Civil Aviation University of China Institute of Robotics and Automatic Information System Nankai University State Key Laboratory of Robotics

A novel error-aware visual localization method is proposed that utilizes vertical planes,such as vertical building facades in urban areas as *** planes,reconstructed from coplanar vertical lines,are robust high-level features if compared with point features or line ***,the error models of vertical lines and vertical planes are built,where maximum likelihood estimation(MLE)is employed to estimate all vertical planes from coplanar vertical ***,the closed-form representation of camera location error variance is ***,the minimum variance camera pose estimation is formulated into a convex optimization problem,and the weight for each vertical plane is obtained by solving this well-studied *** are carried out and the results show that the proposed localization method has an accuracy of about 2 meters,at par with commercial GPS operating in open environments.

关键词： visual localization multiple vertical planes error aware convex optimization satellite images urban environment mobile robot

New puzzle in charmonium decays

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Chinese Physics C 2022年第7期46卷 1-7页

作者： hongpeng wang Chang-Zheng Yuan Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

By analyzing existing data on pseudoscalar charmonium decays,we obtain the ratio of the branching fractions of η_(c)(2S) and η_(c) decays into ten different final states with light *** the first time,we test the two existing theoretical predictions of these decays and find that the experimental data are significantly different from both of *** lack of observation of any decay mode with higher rate in η_(c)(2S)than in η_(c) decays suggests very unusual decay dynamics in pseudoscalar charmonium decays to be *** also report the first model-independent evaluation of the partial width of η_(c)(2S)→yy(2.21^(+0.88)_(-0.64)keV)and improve determination of that of η_(c)→yy(5.43^(+0.41)_(-0.38)KeV).The latter shows a tension with the most recent lattice QCD calculation.

关键词： charmonium decays strong interaction quantumchromodymanics

Autonomous map query:robust visual localization in urban environments using Multilayer Feature Graph

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High Technology Letters 2015年第1期21卷 31-38页

作者：李海丰 wang hongpeng Liu Jingtai College of Computer Science and Technology Civil Aviation University of China Insititute of Robotics and Automatic Information System Nankai University

When a vehicle travels in urban areas, onboard global positioning system （GPS） signals may be obstructed by high-rise buildings and thereby cannot provide accurate positions. It is proposed to perform localization by registering ground images to a 2D building boundary map which is generated from aerial images. Multilayer feature graphs （MFG） is employed to model building facades from the ground images. MFG was reported in the previous work to facilitate the robot scene understand- ing in urhan areas. By constructing MFG, the 2D/3D positions of features can be obtained, inclu- cling line segments, ideal lines, and all primary vertical planes. Finally, a voting-based feature weighted localization method is developed based on MFGs and the 2D building boundary map. The proposed method has been implemented and validated in physical experiments. In the proposed ex- periments, the algorithm has achieved an overall localization accuracy of 2.2m, which is better than commercial GPS working in open environments.

关键词： visual localization urban environment multilayer feature graph( MFG) voting- based method

Static Force-Based Modeling and Parameter Estimation for a Deformable Link Composed of Passive Spherical Joints With Preload Forces

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IEEE/CAA Journal of Automatica Sinica 2021年第11期8卷 1817-1826页

作者： Gaofeng Li Dezhen Song Lei Sun Shan Xu hongpeng wang Jingtai Liu Nankai University Tianjin 300350China Humanoids and Human Centered Mechatronics Research Line Italian Institute of Technology16163 GenovaItaly Department of Computer Science and Engineering Texas A&M UniversityCollege StationTexas 77843 USA Institute of Robotics and Automatic Information System Nankai UniversityTianjin 300350China Tianjin Key Laboratory of Intelligent Robotics Nankai UniversityTianjin 300350China

To balance the contradiction between higher flexibility and heavier load bearing capacity,we present a novel deformable manipulator which is composed of active rigid joints and deformable *** deformable link is composed of passive spherical joints with preload forces between socket-ball *** estimate the load bearing capacity of a deformable link,we present a static force-based model of spherical joint with preload force and analyze the static force propagation in the deformable *** yields an important result that the load bearing capacity of a spherical joint only depends on its radius,preload force,and static friction *** further develop a parameter estimation method to estimate the product of preload force and static friction *** experimental results validate our model.80.4%of percentage errors on the maximum payload mass prediction are below 15%.

关键词： Deformable link parameters identification spherical joint with preload force static force-based model

Effect of annealing treatment on the performance of organic photovoltaic devices using SPFGraphene as electron-accepter material

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Science China(Physics,Mechanics & Astronomy) 2012年第8期55卷 1356-1361页

作者： wang HaiTeng HE DaWei wang YongSheng LIU ZhiYong WU hongpeng wang JiGang ZHAO Yu Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beijing Jiaotong University Beijing 100044 China

We have researched the performances of organic photovoltaic devices with the bulk heterojunction （BHJ） structure using the organic solution-processable functionalized graphene （SPFGraphene） material as the electron-accepter material and P3OT as the donor material. The structural configuration of the device is ITO/PEDOT：PSS/P3OT：PCBM-SPFGraphene/LiF/A1. Given the P3OT/PCBM （1：1） mixture with 8wt% of SPFGraphene, the open-circuit voltage （Voc） of the device reaches 0.64 V, a short-circuit current density （J^c） reaches 5.7 mA/cm2, a fill factor （FF） reaches 0.42, and the power conversion efficiency （7？） reaches 1.53% at illumination at 100 mW/cm2 AM1.5. We further studied the reason for the device performances improvement In the P3OT：PCBM-SPFGraphene composite, the SPFGraphene material acts as exciton dissociation sites and provides the transport pathways of the lowest unoccupied molecular orbital （LUMO）-SPFGraphene-A1. Furthermore, adding SPFGraphene to P3OT results in appropriate energetic distance between the highest occupied molecular orbital （HOMO） and LUMO of the donoffacceptor and provides higher exciton dissociation volume mobility of carrier transport. We have researched the effect of annealing treatment for the devices and found that the devices with annealing treatment at 180℃ show better performances compared with devices without annealed treatment. The devices with annealed treatment show the best performance, with an enhancement of the power conversion efficiency from 1.53% to 1.75%.

关键词： SPFGraphene P3OT HOMO LUMO

Insight to the enhanced microwave absorption of porous N-doped carbon driven by ZIF-8:Competition between graphitization and porosity

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International Journal of Minerals,Metallurgy and Materials 2023年第3期30卷 474-484页

作者： You Zhou hongpeng wang Dan wang Xianfeng Yang Hongna Xing Juan Feng Yan Zong Xiuhong Zhu Xinghua Li Xinliang Zheng School of Physics State Key Laboratory of Photoelectric Technology and Functional MaterialsNorthwest UniversityXi’an 710127China

Porous carbon-based materials are promised to be lightweight dielectric microwave *** understanding the influence of graphitization grade and porous structure on the dielectric parameters is urgently ***,utilizing the low boiling point of Zn,porous N-doped carbon was fabricated by carbonization of ZIF-8(Zn)at different temperature,and the microwave absorption performance was *** porous N-doped carbon inherits the high porosity of ZIF-8 *** increasing the carbonization temperature,the contents of Zn and N elements are decreased;the graphitization degree is improved;however,the specific surface area and porosity are increased first and then *** the carbonization temperature is 1000°C,the porous N-doped carbon behaves enhanced microwave *** an ultrathin thickness of 1.29 mm,the ideal RL reaches-50.57 dB at 16.95 GHz and the effective absorption bandwidth is 4.17 *** mechanism of boosted microwave absorption is ascribed to the competition of graphitization and porosity as well as N dopants,resulting in high dielectric loss capacity and good impedance *** porous structure can prolong the pathways and raise the contact opportunity between microwaves and porous carbon,causing multiple scattering,interface polarization,and improved impedance ***,the N dopants can induce electron polarization and defect *** results give a new insight to construct lightweight carbon-based microwave absorbents by regulating the graphitization and porosity.

关键词： N-doped carbon porosity dielectric impedance matching microwave absorption

An Improved WiFi Indoor Localization Method Combining Channel State Information and Received Signal Strength 36

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An Improved WiFi Indoor Localization Method Combining Channe...

A 3D Coverage Path Planning Approach for Flying Cameras in Nature Environment under Photogrammetric Constraints 36

第36届中国控制会议

作者： Linsheng Zhao hongpeng wang Pengpeng Li Jingtai Liu Institute of Robotics and Automatic Information System Nankai University Tianjin Key Laboratory of Intelligent Robotics

ISBN: (纸本)9781538629185

WiFi indoor localization has attracted much attention owing to the pervasive penetration of wireless local area networks（WLANs） and WiFi enabled mobile *** WiFi indoor localization systems rely on received signal strength（RSS）,which is instability and low space distinguish ***,channel state information（CSI） has been adopted instead of RSS and proven to be an efficient ***,CSI raw data is sensitive to environment *** this paper,we propose an improved WiFi indoor localization system combining CSI and ***,this study applies a time domain filtering method to reduce CSI data dynamic ***,we use the coherence bandwidth for CSI dimensional ***,we extract a robust positioning feature from CSI and ***,an improved weighted k-nearest neighbor algorithm based on kernel methods is used to estimate the *** experiments demonstrate the effectiveness of the proposed system.

关键词： WiFi fingerprint indoor localization channel state information kernel methods

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A 3D Coverage Path Planning Approach for Flying Cameras in N...

Robust hand posture recognition based on RGBD images

第36届中国控制会议

作者： hongpeng wang Hanzhen Li Cheng Zhang Shubao He Jingtai Liu Institute of Robotics and Automatic Information System NanKai University Tianjin Key Laboratory of Intelligent Robotics

ISBN: (纸本)9781538629185

Coverage path planning is the operation of finding a path that covers all the points of a specific *** to the recent advances of hardware technology,Unmanned Aerial Vehicles（UAVs） have multiple use at present besides obvious military applications,such as nature environment 3D *** most of the research focus on finding the coverage path in an planar coverage surface,without considering the photogrammetric constraints,such as constant distance for consistency resolution and normal orientation for *** paper present a modified back-and-forth 3D coverage path planning method for quadrotor with gimbal camera under photogrammetric constraints that can reduce the consumption of time and ***,the 3D terrain is modeled by quasi uniform B-spline surface for a mesh ***,the center of the camera footprint on the terrain surface and the air points can be generated by photogrammetric ***,a modified back-and-forth coverage path planning method has been used to calculate the scan direction and coverage *** experiment results have showed that our method can cover all the waypoints in the air that satisfy all the photogrammetric constraints.

关键词： Coverage Path Planning Flying Camera Photogrammetric Constraints

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Robust hand posture recognition based on RGBD images