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IEEE International Wireless Symposium (IWS)

作者： Changqing Liu Liang Zhang Shijie Huang Chao Wang Xingchuan Yu Xianliang Wu Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University AnHui Province Key Laboratory of simulation and design for Electronic information system Hefei Normal university Hefei China

ISBN: (数字)9781728167039

ISBN: (纸本)9781728167046

A low-profile circularly polarized Metasurfaces antenna based on compact coplanar waveguide (CPW) feed was proposed. The Metasurfaces consists of 16 periodic square-cut metal patches. An hourglass coupled slot was adopted to achieve broadband impedance matching. The antenna has a simple structure and a low cross section, and it can be implemented by a layer of a printed circuit substrate. A circular polarized wave is generated by changing the size of the cut angle of the Metasurfaces, and at the same time, the impedance bandwidth can be widened. To verify the simulation results, a 1λ 0 ×1λ 0 ×0.05λ 0 (at 10 GHz) model antenna was fabricated and measured. The simulation and measurement results show good consistency. The test results show that the -10dB return loss bandwidth reaches 45.3 %, and the circular polarization axis ratio(AR) is less than 3dB with a bandwidth of 18.5%.

关键词： Antenna measurements Polarization Bandwidth Metasurfaces Radar antennas Antenna feeds Coplanar waveguides

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12-Port Hybrid MIMO Antenna Array for 5G Smartphone Applications

12-Port Hybrid MIMO Antenna Array for 5G Smartphone Applicat...

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IEEE International Wireless Symposium (IWS)

作者： Peng Liu Yufa Sun Bingbing Chen Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Anhui Province Key Laboratory of simulation and design for Electronic information system Hefei Normal University Hefei China

ISBN: (数字)9781728167039

ISBN: (纸本)9781728167046

A hybrid twelve-antenna array operating in the 3.3-3.6 GHz and 4.8-5.0 GHz band for multiple input multiple output (MIMO) applications in 5G smartphones is proposed. The proposed hybrid antenna array elements are symmetrically placed along the long edges of the smartphone, and they are composed of two inverted-F antennas (IFA) with different structural parameters. Simulated antenna isolation is better than -14.5 dB without any decoupling structures. Moreover, simulated radiation patterns, antenna efficiencies, and envelop correlation coefficients are also given in the paper.

关键词： Wireless communication 5G mobile communication Structural engineering Smart phones MIMO communication Antenna arrays Antenna radiation patterns

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RETRACTED ARTICLE:Thermal,mechanical,and tribological properties of sodium-montmorillonite-nanoparticle-reinforced polyethersulfone and polytetrafluoroethylene ternary composites

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Friction 2022年第7期10卷 1134-1134页

作者： Shicheng YAN Yahong XUE Yahui HU Shoujun WANG Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin 300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin 300384China College of Mechanical Engineering Tianjin University of TechnologyTianjin 300384China

The Editor-in-Chief has retracted this article[1]because a large number of figures as well significant parts of the text overlap with the 2017 *** by Zhen Zuo[2].All authors agree to this retraction.[1]Yan S C,Xue Y H,Hu Y H,Wang S ***,mechanical,and tribological properties of sodium-montmorillonite-nanoparticlereinforced polyethersulfone and polytetrafluoroethylene ternary ***(2020).https://***/10.1007/s40544-019-0343-x.[2]Zuo *** on tribological property and friction interface interaction of PES/PTFE ***.D ***(China):Yanshan University,2017.

关键词： friction Friction tribological

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An Approach on Visual Detecting Multi-Targets in the Unstructured and Complex Scenes Based on RGB-D Images 5

An Approach on Visual Detecting Multi-Targets in the Unstruc...

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5th International Conference on Automation, Control and Robotics Engineering, CACRE 2020

作者： Tan, Qimeng Sun, Yikun Xin, Pengfei Lin, Yimin Ma, Chao Wang, Xinyu Beijing Institute of Spacecraft System Engineering Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing China Beijing Special Engineering Design and Research Institute Propellant Injection Laboratory Beijing China Beijing University of Posts Telecommunications Institute of Optical Communication Optoelectronics Beijing China Beijing Information Science and Technology University School of Instrument Science and Optoelectronic Engineering Beijing China

ISBN: (纸本)9781728198880

The technology of detecting and identifying multitarget is of significance for robotic visual navigation within the unknown, unstructured, complex scenes, whose result could be considered as important references of 3D map building and path planning for mobile robot. Traditional algorithms of target detection can be applied to 2D images without depth information generally, which is disturbed by few factors such as illumination, view and scale easily. Therefore, an approach on visual detecting multi-target of unstructured and complex scenes based on RGBD images is proposed in this article to solve the above problem, which is composed of extracting descriptor of rotation and scale invariance feature, local encoding of targets, random ferns classifier training, Hough map generation, Hough voting theoretical model and local maximum search. Experimental results have shown that the proposed approach reduce the calculation of extracting and matching local feature, improve the accuracy of object recognition and detection in unknown complex environments, be capable of well robust against few disturbing factors i.e. rotation, scale, illumination, occlusion and non-rigid body deformation. © 2020 IEEE.

关键词： Motion planning

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AoI and Energy Consumption Oriented Dynamic Status Updating in Caching Enabled IoT Networks

AoI and Energy Consumption Oriented Dynamic Status Updating ...

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IEEE Conference on Computer Communications Workshops, INFOCOM Wksps

作者： Chao Xu Xijun Wang Howard H. Yang Hongguang Sun Tony Q. S. Quek Key Laboratory for Agricultural Internet of Things Ministry of Agriculture and Rural Affair Yangling China Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China Information System Technology and Design Pillar Singapore University of Technology and Design Singapore

ISBN: (数字)9781728186955

ISBN: (纸本)9781728186962

Caching has been regarded as a promising technique to alleviate energy consumption of sensors in Internet of Things (IoT) networks by responding to users' requests with the data packets stored in the edge caching node (ECN). For real-time applications in caching enabled IoT networks, it is essential to develop dynamic status update strategies to strike a balance between the information freshness experienced by users and energy consumed by the sensor, which, however, is not well addressed. In this paper, we first depict the evolution of information freshness, in terms of age of information (AoI), at each user. Then, we formulate a dynamic status update optimization problem to minimize the expectation of a long-term accumulative cost, which jointly considers the users' AoI and sensor's energy consumption. To solve this problem, a Markov Decision Process (MDP) is formulated to cast the status updating procedure, and a model-free reinforcement learning algorithm is proposed, with which the challenge brought by the unknown of the formulated MDP's dynamics can be addressed. Finally, simulations are conducted to validate the convergence of our proposed algorithm and its effectiveness compared with the zero-wait baseline policy.

关键词： sensors Heuristic algorithms Energy consumption Internet of Things Vehicle dynamics Optimization Learning (artificial intelligence)

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Estimation of Sensible and Latent Heat Flux Over Mountainous Areas Using the SEBAL Model

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IEEE Transactions on Geoscience and Remote Sensing 2025年 63卷

作者： Wei Fu Bo-Hui Tang Xianguang Ma Dong Fan Xinming Zhu Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming China Yunnan Key Laboratory of Quantitative Remote Sensing Kunming China Yunnan International Joint Laboratory for Integrated Sky-Ground Intelligent Monitoring of Mountain Hazards Kunming China State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Planning and Design Institute of Land and Resources of Yunnan Province Kunming China

Accurately estimating sensible heat (H) and latent heat (LE) in mountainous areas is a significant challenge due to the influence of complex topography factors. Currently, most models have been developed to estimate surface heat flux for flat surfaces without considering the effect of complex geometric terrain structures. In this study, the surface energy balance algorithm for land (SEBAL) coupled with a mountainous net surface radiation ( $R_{n}$ ) calculation method (MSEBAL) was proposed to accurately estimate H and LE in the upstream catchment regions of the Heihe River Basin (HRB). $R_{n}$ was estimated by correcting the solar incoming radiation components using topographic factors, including slope, aspect, sky view factor (SVF), and terrain configuration factor (TCF). The SEBAL and MSEBAL models were applied to satellite remote sensing (RS) data from Landsat 8 images and ground-observed datasets. In situ measurements from the eddy covariance (EC) system of the A’rou superstation were used to validate the estimation accuracy of $R_{n}$ , LE, and H by MSEBAL. The results show that $R_{n}$ , LE, and H estimated by the MSEBAL exhibit good consistency with the validation of in situ measurements. $R_{n}$ estimated by MSEBAL showed a decrease in RMSE from 164.32 to 51.31 W/m2 and a reduction in absolute bias from 154.50 to 10.50 W/m2 compared to SEBAL. The H and LE estimated by MSEBAL exhibit low RMSE and bias, with values of 31.96 and −17.93 W/m2 for H, and 35.67 and −6.18 W/m2 for LE, respectively, compared to SEBAL. The spatial pattern of surface heat fluxes exhibited variations with complex terrain changes. H and LE were found to be higher at mountain peaks, while lower values were observed in valleys. Additionally, H and LE were greater on east- and south-facing slopes that receive more solar radiation compared to west- and north-facing slopes. This study provides an effective tool for estimating surface heat fluxes over mountainous regions.

关键词： Surface topography Heating systems Land surface Estimation Surfaces Remote sensing Monitoring Land surface temperature Data models Mathematical models

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A Novel Engineering Education Innovation Pattern with design Ideas and Robot Maker Practice

A Novel Engineering Education Innovation Pattern with Design...

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13th International Conference on Axiomatic design, ICAD 2019

作者： Zhu, Aibin Shen, Huang Shen, Zhitao Tu, Yao Song, Jiyuan Shaanxi Key Laboratory of Intelligent Robots Xi'an710049 China Institute of Robotics and Intelligent Systems Xi'an Jiaotong University Xi'an710049 China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi'an710049 China

Traditional engineering education of innovative thinking mainly focused on knowledge imparting, thinking and learning, but it weakens the cultivation of students' practical ability. In this paper, a new pattern of innovative thinking engineering education is proposed, which combines abstract design innovation with specific robot maker practice. By offering general course for all professional students, it teaches the theory, methods and tools of systematic innovative thinking, and cultivates students' system design methods and innovative thinking. Taking the design and production process of robots as the object and content of practical teaching, the traditional teaching pattern centered on teachers, classrooms and textbooks is changed, teachers' reflection on teaching is promoted, so that it can be truly changedfrom a lecturer to an inspirator of learning, at the same time, teaching flexibility is increased, and students' highlevel thinking and practical abilities are improved. Classroom statistics show that 92.14% of the students think that their innovative thinking ability has been improved, and 90.71% of the students consider that their practical ability has been enhanced. It shows that the engineering education innovation pattern with design ideas and robot maker practice can inspire students' innovative thinking, while improving students' robotic practical ability. © 2019 The Authors, published by EDP Sciences.

关键词： Students

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Multi-objective Dimensional Optimization of a 3-DOF Translational PKM Considering Transmission Properties

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International Journal of Automation and computing 2019年第6期16卷 748-760页

作者： Song Lu Yang-Min Li Bing-Xiao Ding Department of Electromechanical Engineering University of MacaoTaipaMacao 853China Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong 852China Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System Tianjin University of TechnologyTianjin 300384China

Multi-objective dimensional optimization of parallel kinematic manipulators(PKMs) remains a challenging and worthwhile research endeavor. This paper presents a straightforward and systematic methodology for implementing the structure optimization analysis of a 3-prismatic-universal-universal(PUU) PKM when simultaneously considering motion transmission, velocity transmission and acceleration transmission. Firstly, inspired by a planar four-bar linkage mechanism, the motion transmission index of the spatial parallel manipulator is based on transmission angle which is defined as the pressure angle amongst limbs. Then, the velocity transmission index and acceleration transmission index are derived through the corresponding kinematics model. The multi-objective dimensional optimization under specific constraints is carried out by the improved non-dominated sorting genetic algorithm(NSGA Ⅱ), resulting in a set of Pareto optimal solutions. The final chosen solution shows that the manipulator with the optimized structure parameters can provide excellent motion, velocity and acceleration transmission properties.

关键词： Multi-objective optimization parallel kinematic manipulator transmission property non-dominated sorting genetic algorithm(NSGA Ⅱ)

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Corrigendum to “Load-bearing behaviors of sandwich plates with non-uniformly distributed grid cores: Dynamic impact and blast” [Mater. Today Commun., vol. 40, (2024), 110163]

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Materials Today Communications 2024年 41卷

作者： Youlong Wang Haixia Yang Jie Chen Quanjin Ma Yiheng Song Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education School of Civil Engineering Southeast University Nanjing 211189 PR China School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen 518055 PR China School of Engineering The University of Tokyo Tokyo 113-8656 Japan

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NURBS Interpolator With Pre-compensation Based on Discrete Inverse Transfer Function for CNC High-precision Machining

Research Square

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Research Square 2021年

作者： Wang, Taiyong Cao, Libo Zhang, Yongbin Dong, Jingchuan Jia, Songhui Tian, Chong Liu, Qingjian Renai College Tianjin University Tianjin301636 China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China School of Mechanical Engineering Tianjin University No.135 YaGuan Road Jinnan District Tianjin300354 China

In the field of CNC machining, high-speed and high-precision machining has been regarded as the key research by many scholars. In conventional methods, high-speed machining and high-precision machining are contradictory. It is inevitable to reduce the feedrate to improve the processing accuracy. In the paper, a pre-compensation based on discrete inverse transfer function (PDIT) theory is proposed. PDIT is able to improve machining accuracy by reducing contour errors without decreasing feedrate. The proposed PDIT theory is divided into three parts, NURBS interpolator, feedrate scheduling, and interpolator with pre-compensation. The NURBS interpolator has greatly advantage to interpolate the parameter curve directly. Therefore, the paper adopts the NURBS interpolator to accomplish interpolation. In the feedrate scheduling, S-type flexible acceleration and deceleration are used for path planning, and the maximum starting feedrate is obtained with the feedrate constraint. In the interpolator with pre-compensation, the NURBS interpolator is pre-compensated by PDIT. For inputs, the response of transfer function reach steady-state response with a little time. Before reaching steady-state response, the unsteady response exists in the transfer function. The unsteady response usually sustains tens of interpolation periods and must be lead contour error in machining. Hence, the PDIT theory is employed to compensate the contour error causing by the unsteady response of transfer function to NURBS interpolator. The drive system is a transfer function, so the unsteady response of drive system cause machining errors before reaching the steady-state response. In the paper, the NURBS interpolator is pre-compensated by PDIT theory before the drive system to reduce contour errors and improve machining accuracy. Finally, the performance of the proposed PDIT is evaluated by simulation experiments. The experimental results illustrate that PDIT theory obviously improve the machining accura

关键词： Transfer functions

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