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Digital modulation classification using multi-layer perceptron and time-frequency features

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Journal of Systems Engineering and Electronics 2007年第2期18卷 249-254页

作者： yuan ye Mei Wenbo Dept. of Industrial Design and Information Engineering Beijing Institute of Clothing Technology Beijing 100029 P. R. China Dept. of Electronic Engineering Beijing Inst. of Technology Beijing 100081 P. R. China

Considering that real communication signals corrupted by noise are generally nonstationary, and timefrequency distributions are especially suitable for the analysis of nonstationary signals, time-frequency distributions are introduced for the modulation classification of communication signals： The extracted time-frequency features have good classification information, and they are insensitive to signal to noise ratio （SNR） variation. According to good classification by the correct rate of a neural network classifier, a multilayer perceptron （MLP） classifier with better generalization, as well as, addition of time-frequency features set for classifying six different modulation types has been proposed. Computer simulations show that the MLP classifier outperforms the decision-theoretic classifier at low SNRs, and the classification experiments for real MPSK signals verify engineering significance of the MLP classifier.

关键词： Digital modulation classification Time-frequency feature Time-frequency distribution Multi-layer perceptron.

Super-resolution DOA estimation for correlated off-grid signals via deep estimator

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Journal of Systems Engineering and Electronics 2022年第6期33卷 1096-1107页

作者： WU Shuang yuan ye ZHANG Weike yuan Naichang Facility Design and Instrumentation Institute China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System National University of Defense TechnologyChangsha 410073China

This paper develops a deep estimator framework of deep convolution networks(DCNs)for super-resolution direction of arrival(DOA)*** addition to the scenario of correlated signals,the quantization errors of the DCN are the major *** our deep estimator framework,one DCN is used for spectrum estimation with quantization errors,and the remaining two DCNs are used to estimate quantization *** propose training our estimator using the spatial sampled covariance matrix directly as our deep estimator’s input without any feature extraction ***,we reconstruct the original spatial spectrum from the spectrum estimate and quantization errors ***,the feasibility of the proposed deep estimator is analyzed in detail in this *** the deep estimator is appropriately trained,it can recover the correlated signals’spatial spectrum fast and *** results show that our estimator performs well in both resolution and estimation error compared with the state-of-the-art algorithms.

关键词： off-grid direction of arrival(DOA)estimation deep convolution network(DCN) correlated signal quantization error super-resolution

Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng Xing ye yuan Gen Li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method

Influence of differential longitudinal cyclic pitch on flight dynamics of coaxial compound helicopter

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Chinese Journal of Aeronautics 2023年第9期36卷 207-220页

作者： Yanqin ZHAO ye yuan Renliang CHEN National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Aerospace Engineering Swansea UniversitySwansea city SA18ENUK

The Differential Longitudinal Cyclic Pitch(DLCP)in coaxial compound helicopter is found to be useful in mitigating low-speed rotor interactions and improving flight *** complex mutual interaction is simulated by a revised rotor aerodynamics model,where an improved Blade Element Momentum Theory(BEMT)is *** with the rotor inflow distributions and aircraft trim results from literature validate the accuracy of the ***,the influence of the DLCP on the flight dynamics of the aircraft is *** trim characteristics indicate that a negative DLCP can reduce collective and differential collective inputs in low speed forward flight,and the negative longitudinal gradient is ***,a moderate DLCP can reduce the rotor and total power consumption by 4.68%and 2.9%,*** DLCP further increases,the increased propeller power and unbalanced thrust allocation offset the *** high-speed flight,DLCP does not improve the performance except for extra lateral and heading stick *** addition,the tip clearance is degraded throughout the speed envelope due to the differential pitching moment and the higher thrust from the lower ***,the changed rotor efficiency and induced velocity alter low-speed dynamic stability and *** pitch and roll subsidences are slightly degraded with the DLCP,while the heave subsidence,dutch roll and phugoid modes are ***,the on-axis controllability,including collective,differential collective pitch,longitudinal and lateral cyclic pitches,varies with DLCP due to its effect on rotor efficiency and inflow *** conclusion,a reasonable DLCP is recommended to adjust the rotor interaction and improve aircraft performance,and further to alter the flight dynamics and aerodynamics of aircraft.

关键词： Blade element momentum theory Coaxial compound helicopter Differential longitudinal cyclic pitch Interaction model Tip clearance

Empirical mode decomposition using variable filtering with time scale calibrating

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1076-1081页

作者： yuan ye Mei Wenbo Wu Siliang yuan Qi School of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China School of Industrial Design and Information Engineering Beijing Inst. of Clothing Technology Beijing 100029 P. R. China The Science and Technology Committee of China Aerospace Science and Industry Corporation Beijing 100854 P. R. China

A novel and efficient method for decomposing a signal into a set of intrinsic mode functions （IMFs） and a trend is proposed. Unlike the original empirical mode decomposition （EMD）, which uses spline fits to extract variations from the signal by separating the local mean from the fluctuations in the decomposing process, this new method being proposed takes advantage of the theory of variable finite impulse response （FIR） filtering where filter coefficients and breakpoint frequencies can be adjusted to track any peak-to-peak time scale changes. The IMFs are results of a multiple variable frequency response FIR filtering when signals pass through the filters. Numerical examples validate that in contrast with the original EMD, the proposed method can fine-tune the frequency resolution and suppress the aliasing effectively.

关键词： empirical mode decomposition variable FIR filtering time scale calibrating.

Bionic Leaf Simulating the Thermal Effect of Natural Leaf Transpiration

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Journal of Bionic Engineering 2014年第1期11卷 90-97页

作者： Zhi yuan Hong ye Shimin Li Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei 230027 P. R. China

We proposed a kind of bionic leaf to simulate the thermal effect of leaf transpiration. The bionic leaf was firstly designed to be composed of a green coating, a water holding layer, a Composite Adsorbent （CS） layer and an adsorption-desorption rate controlling layer. A thermophysical model was established for the bionic leaf, and the dynamic simulation results reveal that the water holding layer is not necessary; a CS of high thermal conductivity should be selected as the CS layer; the adsorp- tion-desorption rate controlling layer could be removed due to the low adsorption-desorption rate of the CS; and when CaC12 mass fraction of the CS reaches 40%; the bionic leaf could simulate the dynamic thermal behavior of the natural leaf. Based on the simulation results, we prepared bionic leaves with different CaC12 content. The thermographies of the bionic leaf and the natural leaf were shot using the Infrared Thermal Imager. The measured average radiative temperature difference between the bionic and natural leaves is less than 1.0 ℃.

关键词： bionic leaf composite sorbent transpiration thermal effect leaf temperature

Design and Analysis of a Magnetic Bearings with Three Degrees of Freedom

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Chinese Journal of Mechanical Engineering 2019年第1期32卷 142-151页

作者： ye yuan Yukun Sun Qianwen Xiang School of Electrical and Information Engineering Jiangsu University College of Electrical Engineering Nanjing Institute of Technology

The current research of supporting and transmission system in flywheel energy storage system(FESS) focuses on the low consumption design. However, friction loss is a non-negligible factor in the high-speed but lightweight FESS energy and momentum storage with mechanical-type supporting system. In order to realize the support system without mechanical loss and to maximize the e ciency of the flywheel battery, a permanent magnet biased magnetic bearings(PMBMB) is applied to the FESS with the advantages of low loss, high critical speed, flexible controllability and compact structure. In this frame, the relevant research of three degrees of freedom(3-DOF) PMBMB for a new type FESS is carried out around the working principle, structural composition, coupling characteristics analysis, mathematical model, and structural design. In order to verify the performance of the 3-DOF PMBMB, the radial force mathematical model and the coupling determination equations of radial two DOF are calculated according to an equivalent magnetic circuit, and radial–axial coupling is analyzed through finite element analysis. Moreover, a control system is presented to solve the control problems in practical applications. The rotor returns to the balanced position in 0.05 s and maintains stable suspension. The displacement fluctuation is approximately 40 μm in the y direction and 30 μm in the x direction. Test results indicate that the dynamic rotor of the proposed flywheel energy storage system with PMBMB has excellent characteristics, such as good start-of-suspension performance and stable suspension characteristics. The proposed research provides the instruction to design and control a low loss support system for FESS.

关键词： Flywheel energy storage system Magnetic bearings Degrees of freedom Coupling Finite element analysis

SDGNN: Symmetry-Preserving Dual-Stream Graph Neural Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1717-1719页

作者： Jiufang Chen ye yuan Xin Luo the College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065 the Chongqing Key Laboratory of Big Data and Intelligent Computing Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China the College of Computer and Information Science Southwest UniversityChongqing 400715China IEEE

Dear Editor,This letter proposes a symmetry-preserving dual-stream graph neural network(SDGNN) for precise representation learning to an undirected weighted graph(UWG). Although existing graph neural networks(GNNs) are influential instruments for representation learning to a UWG, they invariably adopt a unique node feature matrix for illustrating the sole node set of a UWG.

关键词： representation preserving undirected

Mixed Two-and Eight-level Fractional Factorial Split-plot Designs Containing Clear Effects

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Acta Mathematicae Applicatae Sinica 2016年第4期32卷 995-1004页

作者： ye yuan Sheng-li ZHAO School of Statistics Qufu Normal University

Fractional factorial split-plot （FFSP） designs are useful in practical experiments. When the num- bers of levels of the factors are not all equal in an experiment, mixed-level design is selected. This paper investigates the conditions of a resolution III or IV FFSP design with both two-level and eight-level factors to have various clear effects, including two types of main effects and three types of two-factor interaction compo- nents.

关键词： split-plot design mixed-level design clear