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Intelligent and Converged Networks 2021年第1期2卷 16-29页

作者： Yu Zhou Hatim Alhazmi Mohsen H.Alhazmi Alhussain Almarhabi Mofadal Alymani Mingju He shengliang Peng Abdullah Samarkandi zikang sheng Huaxia Wang Yu-Dong Yao Department of Electrical and Computer Engineering Stevens Institute of TechnologyHobokenNJ 07030USA the College of Information Science and Engineering Huaqiao UniversityXiamen 361021China the College of Engineering Architecture and TechnologyOklahoma State UniversityStillwaterOK 74078-1010USA

Radio spectrum awareness,including understanding radio signal activities,is crucial for improving spectrum utilization,detecting security vulnerabilities,and supporting adaptive *** tasks include spectrum sensing,identifying systems and terminals,and understanding various protocol *** this paper,we investigate various identification and classification tasks related to fading channel parameters,signal distortions,Medium Access Control(MAC)protocols,radio signal types,and cellular ***,we utilize deep learning methods in those identification and classification *** evaluations demonstrate the effectiveness of deep learning in those radio spectrum awareness tasks.

关键词： cellular system deep learning signal classification spectrum awareness Convolutional Neural Network(CNN)

A local toolpath smoothing method for a five-axis hybrid machining robot

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Science China(Technological Sciences) 2023年第3期66卷 721-742页

作者： SHI zikang ZHANG WeiJia DING Ye State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Smooth transitions between two adjacent five-axis toolpaths can reduce feedrate fluctuation,improving machining quality and *** robots’flexibility to adjust the orientation is advantageous in five-axis machining,but their kinematic issues raise challenges for toolpath *** paper proposes a G3continuous toolpath smoothing method for a hybrid robot.B-splines in the machine coordinate system(MCS)are inserted at corners to synchronize five-axis *** transition errors of the tool position and orientation paths are estimated with the golden section *** approximation errors are constrained by adaptively modifying the B-splines,i.e.,adding anchor points and optimizing the control points.A bisection search method is proposed for these geometric modifications,guaranteeing the user-defined error tolerance *** to the method based on the workpiece coordinate system(WCS),the proposed framework generates a smoother trajectory under the same error tolerance *** and experiments are provided to validate the effectiveness.

关键词： hybrid robot toolpath smoothing B-spline five-axis machining trajectory generation

数字乡村建设如何促进后发地区农民收入增长——来自935个革命老区县的经验证据

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云南农业大学学报（社会科学版） 2025年第1期19卷 29-36页

作者：曾永明钟子康江西财经大学经济学院江西南昌330013 中山大学社会学与人类学学院广东广州510275

文章聚焦数字乡村建设与革命老区农民收入,基于全国935个革命老区县构建空间计量模型,探究数字乡村建设对革命老区农民收入的影响机制与空间溢出效应。研究表明:数字乡村建设对革命老区具有显著的增收效应,有助于促进革命老区县农民收... 详细信息

文章聚焦数字乡村建设与革命老区农民收入,基于全国935个革命老区县构建空间计量模型,探究数字乡村建设对革命老区农民收入的影响机制与空间溢出效应。研究表明:数字乡村建设对革命老区具有显著的增收效应,有助于促进革命老区县农民收入提高。这种增收效应具有包容性增长优势,有助于帮助西部革命老区县、革命老区脱贫县等低收入地区实现更高水平的收入提升。同时,数字乡村建设的增收效应具有空间溢出效应,但这种溢出效应还仅发生在革命老区非贫困县间,脱贫县间的溢出效应还未完全形成。数字乡村建设对革命老区的增收效应可通过提高创业活跃度、电商发展水平两个渠道实现。文章研究结论为有效推进革命老区等落后地区数字乡村建设和共同富裕补充一定的经验证据和政策参考。

关键词：革命老区县数字乡村建设农民收入增长共同富裕空间计量模型

Comparison of dimension reduction methods for DEA under big data via Monte Carlo simulation

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Journal of Management Science and Engineering 2021年第4期6卷 363-376页

作者： zikang Chen Song Han School of Economics Renmin University of ChinaBeijing100872China Institute of Operations Research and Mathematical Economics School of EconomicsRenmin University of ChinaBeijing100872China

Data with large dimensions will bring various problems to the application of data envelopment analysis(DEA).In this study,we focus on a“big data”problem related to the considerably large dimensions of the input-output *** four most widely used approaches to guide dimension reduction in DEA are compared via Monte Carlo simulation,including principal component analysis(PCA-DEA),which is based on the idea of aggregating input and output,efficiency contribution measurement(ECM),average efficiency measure(AEC),and regression-based detection(RB),which is based on the idea of variable *** compare the performance of these methods under different scenarios and a brand-new comparison benchmark for the simulation *** addition,we discuss the effect of initial variable selection in RB for the first *** on the results,we offer guidelines that are more reliable on how to choose an appropriate method.

关键词： Data envelopment analysis Big data Data dimension reduction method

Prediction of Ground Vibration Induced by Rock Blasting Based on Optimized Support Vector Regression Models

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3147-3165页

作者： Yifan Huang zikang Zhou Mingyu Li Xuedong Luo Faculty of Engineering China University of GeosciencesWuhan430074China Institute of Geological Survey China University of GeosciencesWuhan430074China

Accurately estimating blasting vibration during rock blasting is the foundation of blasting vibration *** this study,Tuna Swarm Optimization(TSO),Whale Optimization Algorithm(WOA),and Cuckoo Search(CS)were used to optimize two hyperparameters in support vector regression(SVR).Based on these methods,three hybrid models to predict peak particle velocity(PPV)for bench blasting were ***-eight samples were collected to establish the PPV database,eight initial blasting parameters were chosen as input parameters for the predictionmodel,and the PPV was the output *** predictive performance evaluation indicators,the coefficient of determination(R2),rootmean square error(RMSE),mean absolute error(MAE),and a10-index were *** normalizedmutual information value is then used to evaluate the impact of various input parameters on the PPV prediction *** to the research findings,TSO,WOA,and CS can all enhance the predictive performance of the SVR *** TSO-SVR model provides the most accurate *** performances of the optimized hybrid SVR models are superior to the unoptimized traditional prediction *** maximum charge per delay impacts the PPV prediction value the most.

关键词： Blasting vibration metaheuristic algorithms support vector regression peak particle velocity normalized mutual information

Constrained docking control for shipborne UAV SideArm recovery

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Chinese Journal of Aeronautics 2024年第5期37卷 39-59页

作者： zikang SU Zhuolin XING Xuebing LI Chuntao LI Xinwei WANG Honglun WANG College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

In this work,we sought to investigate constrained docking control during shipborne SideArm recovery of an Unmanned Aerial Vehicle(UAV)under preassigned safe docking constraints,rough ocean environments,and different initial *** aim was to solve the UAV tracking-lag problem that manifests when attempting to dock with a rapidly moving SideArm and to improve the accuracy and rapidity of ***,together with the formulations of the shipborne SideArm system and environmental airflows,the affine nonlinear dynamics of the hook was established to reduce tracking ***,echo state network approximators with good approximation capacity and low computational consumption were designed to accurately approximate the UAV’s unknown nonlinear *** feedforward compensation provided by these approximators,a nonlinear-mapping-based constrained docking control law was developed for shipborne SideArm recovery of *** approach to controlling the docking trajectory and the forward docking speed of the UAV can achieve rapid and exact docking with a moving SideArm,without violating the preassigned safe docking-constraint *** under different docking scenarios were used to validate the effectiveness and advantages of the proposed docking-control algorithm.

关键词： SideArm recovery Unmanned aerial vehicle Docking control Nonlinear mapping Echo state network

Highly-efficient thermoelectric-driven light-emitting diodes based on colloidal quantum dots

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Nano Research 2022年第10期15卷 9402-9409页

作者： Xing Lin Xingliang Dai zikang Ye Yufei Shu Zixuan Song Xiaogang Peng Key Laboratory of Excited-State Materials of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 310027China College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China State Key Laboratory of Silicon Materials Department of Material Science and EngineeringZhejiang UniversityHangzhou 310027China College of Optical Science and Engineering Zhejiang UniversityHangzhou 310027China

Driven by sub-bandgap electric work and Peltier heat,thermoelectric-driven light-emitting diodes(TED-LEDs)not only offer much enhanced power-conversion-efficiency but also eliminate the waste heat generated during the operation of ***,costeffective and high-efficiency TED-LEDs are not readily accessible for the epitaxially grown III-V LEDs due to the high chip cost and efficiency droop at low-medium brightness(current densities).Here we show that electroluminescence of colloidal quantum dots(QDs)LEDs(QLEDs)circumvents the deficiencies faced by conventional *** optimal red-emitting device fabricated by cost-effective solution processing technics exhibits external-and internal-power-conversion-efficiency of 21.5%and 93.5%at 100 cd/m^(2),suited for high-efficiency solid-state lighting and high-resolution *** this brightness,the electric driving voltage(V)of 1.89 V is lower than the photon voltage(Vp=hv/q=1.96 V,q being the elemental charge).With typical Vp=1.96 V,electroluminescence can be detected with the driving voltage as low as 1.0-1.2 *** of the thermoelectric-driven QLEDs(TED-QLEDs)remains ideally diffusion-dominated with the driving voltage lower than~1.5 V,and further improvement on charge transport is expected to extend the linear ideality to all practical driving voltages.

关键词： light-emitting diodes up-conversion electroluminescence colloidal quantum dot thermoelectric-driven power efficiency

Laser spot associated high-saturation phosphor-in-glass film for transmissive and reflective high-brightness laser lighting

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Journal of Advanced Ceramics 2023年第9期12卷 1821-1832页

作者： zikang Yu Jiuzhou Zhao Qing Wang Yun Mou Mingxiang Chen Yang Peng School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Integrated Circuits Sun Yat-sen UniversityShenzhen 518107China

Phosphor-in-glass(PiG)film is a promising luminescent material in high-brightness laser lighting for its advantages of high efficiency,outstanding color quality,and low-cost preparation,which must bear high laser power(LP)and laser power density(LPD)simultaneously to enable high-luminance ***,laser spot associated high-saturation PiG film was proposed for transmissive and reflective high-brightness laser *** types of PiG films were prepared by printing and sintering La_(3)Si_(6)N_(11):Ce^(3+)(LSN)phosphor-borosilicate glass pastes on a sapphire substrate(PiG-S)and an AlN substrate(PiG-A),*** PiG films with perfect crystal structure of phosphor were reliably bonded on the *** effects of laser spot areas on the luminescence saturation of LP and LPD were investigated in the PiG *** the increase of laser spot area from 0.5 to 2.5 mm^(2),the LP threshold of PiG films is gradually raised,while the LPD threshold of PiG films is *** PiG-S withstands a high LP of 23.46 W and a high LPD of 20.64 W/mm^(2),enabling white light with a luminous flux of 3677 *** PiG-A withstands a high LP of 41.12 W and a high LPD of 35.56 W/mm^(2),enabling white light with a luminous flux of 2882 ***,the PiG-A maintains lower working temperature compared with the PiG-S,and the temperatures reduce with the increasing laser spot *** results demonstrate that the laser spot associated PiG films realize high saturation thresholds of LP and LPD simultaneously,and enable high luminance for laser lighting.

关键词： phosphor-in-glass(PiG)film white laser lighting high luminescence saturation laser spot regulation opto-thermal performances

High-precision stress determination in photoelasticity

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Applied Mathematics and Mechanics(English Edition) 2022年第4期43卷 557-570页

作者： zikang XU Yongsheng HAN Hongliang SHAO Zhilong SU Ge HE Dongsheng ZHANG Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Shandong Water Conservancy Vocational College Rizhao 276826Shandong ProvinceChina Shanghai Institute of Space Craft Equipment Shanghai 200240China

Stress separation is usually achieved by solving differential equations of equilibrium after parameter determination from isochromatics and *** numerical error resulting from the stress determination is a main concern as it is always a function of parameters in *** improve the accuracy of stress calculation,a novel meshless barycentric rational interpolation collocation method(BRICM)is *** derivatives of the shear stress on the calculation path are determined by using the differential matrix which converts the differential form of the equations of equilibrium into a series of algebraic *** advantage of the proposed method is that the auxiliary lines,grids,and error accumulation which are commonly used in traditional shear difference methods(SDMs)are not *** and experimental results indicate that the proposed meshless method is able to provide high computational accuracy in the full-field stress determination.

关键词： photoelasticity stress determination barycentric rational interpolation collocation method differential matrix

Self-assembling nanoarchitectonics of low dimensional semiconductors for circularly polarized luminescence

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Journal of Materiomics 2023年第4期9卷 683-700页

作者： Xiongbin Wang Xuanyu Zhang Huan Liu zikang Tang Rui Chen Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen518055China Institute of Applied Physics and Materials Engineering University of MacaoAvenida da UniversidadeTaipaMacao999078China

Recently,the development of materials with circularly polarized luminescence(CPL)has attracted numerous attentions owing to their potential applications in various *** diverse mechanisms for the origin of chiroptical properties in low dimensional semiconductors(LDS),the self-assembly approach provides a powerful technique for acquisition of strong chiroptical *** from this approach,LDS could be endowed with CPL in which the dissymmetry factor,a vital parameter for evaluating the performance of CPL,could be greatly *** this review,state-of-the-art of selfassembled LDS will be *** current challenges and perspectives in this emerging field are also *** review could not only provide insights of the fundamentals of self-assembled chirality,but also shine light for designing CPL-active functional nanomaterials toward their applications based on novel optoelectronic devices.

关键词： Circularly polarized luminescence Chirality Low dimensional semiconductor Self-assembly Optoelectronics