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Multi-objective linear fractional inventory model with possibility and necessity constraints under generalised intuitionistic fuzzy set environment

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CAAI Transactions on Intelligence Technology 2019年第3期4卷 175-181页

作者： Totan Garai Harish Garg Department of Mathematics Silda Chandra Sekhar CollegeJhargram-721515West BengalIndia School of Mathematics Thapar Institute of Engineering&TechnologyDeemed UniversityPatiala-147004PunjabIndia

This study presented a multi-objective linear fractional inventory (LFI) problem with generalised intuitionistic fuzzy numbers. In modelling, the authors have assumed the ambiances where generalised trapezoidal intuitionistic fuzzy numbers (GTIFNs) used to handle the uncertain information in the data. Then, the given multi-objective generalised intuitionistic fuzzy LFI model was transformed into its equivalent deterministic linear fractional programming problem by employing the possibility and necessity measures. Finally, the applicability of the model is demonstrated with a numerical example and the sensitivity analysis under several parameters is investigated to explore the study.

关键词： Multi-objective linear fractional inventory model possibility and necessity constraints generalised intuitionistic fuzzy set environment

Stability of the linear chain structure for 12C in covariant density functional theory on a 3D lattice

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 6-13页

作者： ZhengXue Ren ShuangQuan Zhang PengWei Zhao Naoyuki Itagaki Joachim AMaruhn Jie Meng State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Yukawa Institute for Theoretical Physics Kyoto UniversityKyoto 606-8502Japan Institut fur Theoretische Physik Goethe-UniversitatMax-von-Laue-Str.160438 Frankfurt am MainGermany Department of Physics University of StellenboschStellenbosch 7600South Africa

The stability of the linear chain structure of three α clusters for 12C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved on a 3D lattice with the inverse Hamiltonian and the Fourier spectral methods. Starting from a twisted three α initial configuration, it is found that the linear chain structure is stable when the rotational frequency is within the range of ~2.0-~2.5 MeV. Beyond this range, the final states are not stable against fission. By examining the density distributions and the occupation of single-particle levels, however, these fissions are found to arise from the occupation of unphysical continuum with large angular momenta. To properly remove these unphysical continuum, a damping function for the cranking term is introduced. Eventually, the stable linear chain structure could survive up to the rotational frequency ~3.5 MeV, but the fission still occurs when the rotational frequency approaches ~4.0 MeV.

关键词： covariant density functional theory cranking model 3D lattice space linear chain structure alpha-cluster structure collective rotation 12C

Anefficient parallel and distributed solution to nonconvex penalized linear SVMs

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Frontiers of Information Technology & Electronic Engineering 2020年第4期21卷 587-603页

作者： Lei GUAN Tao SUN Lin-bo QIAO Zhi-hui YANG Dong-sheng LI Ke-shi GE Xi-cheng LU College of Computer National University of Defense TechnologyChangsha 410073China School of Computer Science Fudan UniversityShanghai 201203China Shanghai Key Laboratory of Data Science Shanghai 201203China

Support vector machines(SVMs)have been recognized as a powerful tool to perform linear classification.When combined with the sparsity-inducing nonconvex penalty,SVMs can perform classification and variable selection simultaneously.However,the nonconvex penalized SVMs in general cannot be solved globally and efficiently due to their nondifferentiability,nonconvexity,and nonsmoothness.Existing solutions to the nonconvex penalized SVMs typically solve this problem in a serial fashion,which are unable to fully use the parallel computing power of modern multi-core machines.On the other hand,the fact that many real-world data are stored in a distributed manner urgently calls for a parallel and distributed solution to the nonconvex penalized SVMs.To circumvent this challenge,we propose an efficient alternating direction method of multipliers(ADMM)based algorithm that solves the nonconvex penalized SVMs in a parallel and distributed way.We design many useful techniques to decrease the computation and synchronization cost of the proposed parallel algorithm.The time complexity analysis demonstrates the low time complexity of the proposed parallel algorithm.Moreover,the convergence of the parallel algorithm is guaranteed.Experimental evaluations on four LIBSVM benchmark datasets demonstrate the efficiency of the proposed parallel algorithm.

关键词： linear classification Support vector machine(SVM) Nonconvex penalty Alternating direction method of multipliers(ADMM) Parallel algorithm

Joint calibration algorithm for gain-phase and mutual coupling errors in uniform linear array

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Chinese Journal of Aeronautics 2016年第4期29卷 1065-1073页

作者： Li Weixing Lin Jianzhi Zhang Yue Chen Zengping Science and Technology on Automatic Target Recognition Laboratory National University of Defense Technology

The effect of gain-phase perturbations and mutual coupling significantly degrades the performance of digital array radar(DAR). This paper investigates array calibration problems in the scenario where the true locations of auxiliary sources deviate from nominal values but the angle intervals are known. A practical algorithm is proposed to jointly calibrate gain-phase errors and mutual coupling errors. Firstly, a simplified model of the distortion matrix is developed based on its special structure in uniform linear array(ULA). Then the model is employed to derive the precise locations of the auxiliary sources by one-dimension search. Finally, the least-squares estimation of the distortion matrix is obtained. The algorithm has the potential of achieving considerable improvement in calibration accuracy due to the reduction of unknown parameters. In addition,the algorithm is feasible for practical applications, since it requires only one auxiliary source with the help of rotation platforms. Simulation results demonstrate the validity, robustness and high performance of the proposed algorithm. Experiments were carried out using an S-band DAR test-bed.The results of measured data show that the proposed algorithm is practical and effective in application.

关键词： Calibration accuracy Digital array Gain and phase errors Least-squares Mutual coupling Uniform linear array

Identification of heavy metal-contaminated Tegillarca granosa using laser-induced breakdown spectroscopy and linear regression for classification

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Plasma Science and Technology 2020年第8期22卷 151-159页

作者：谢忠好孟留伟冯西安陈孝敬陈熙袁雷鸣石文黄光造衣铭 School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072People's Republic of China College of Physical and Electronic Information Engineering Wenzhou UniversityWenzhou 325035People's Republic of China Research and Development Department Hangzhou Goodhere Biotechnology Co.LtdHangzhou 311100People's Republic of China Research and Development Department Hangzhou Weizan Technology Co.LtdHangzhou 311100People's Republic of China

Tegillarca granosa(T.granosa)is susceptible to heavy metals,which may pose a threat to consumer health.Thus,healthy and polluted T.granosa should be distinguished quickly.This study aimed to rapidly identify heavy metal pollution by using laser-induced breakdown spectroscopy(LIBS)coupled with linear regression classification(LRC).Five types of T.granosa were studied,namely,Cd-,Zn-,Pb-contaminated,mixed contaminated,and control samples.Threshold method was applied to extract the significant variables from LIBS spectra.Then,LRC was used to classify the different types of T.granosa.Other classification models and feature selection methods were used for comparison.LRC was the best model,achieving an accuracy of 90.67%.Results indicated that LIBS combined with LRC is effective and feasible for T.granosa heavy metal detection.

关键词： shellfish laser-induced breakdown spectrometry heavy metal linear regression classification

linear coloring of graphs embeddable in a surface of nonnegative characteristic

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Science China Mathematics 2009年第5期52卷 991-1003页

作者： WANG WeiFan LI Chao Department of Mathematics Zhejiang Normal UniversityJinhua 321004China

A proper vertex coloring of a graph G is linear if the graph induced by the vertices of any two color classes is the union of vertex-disjoint paths. The linear chromatic number lc(G) of the graph G is the smallest number of colors in a linear coloring of G. In this paper, we prove that every graph G with girth g(G) and maximum degree Δ(G) that can be embedded in a surface of nonnegative characteristic has lc(G) = Δ(2G )+ 1 if there is a pair (Δ, g) ∈ {(13, 7), (9, 8), (7, 9), (5, 10), (3, 13)} such that G satisfies Δ(G) Δ and g(G) g.

关键词： linear coloring graph of nonnegative characteristic girth maximum degree

Two freedom linear parameter varying μ synthesis control for flight environment testbed

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Chinese Journal of Aeronautics 2019年第5期32卷 1204-1214页

作者： Meiyin ZHU Xi WANG Zhihong DAN Song ZHANG Xitong PEI School of Energy and Power Engineering Beihang University Collaborative Innovation Center for Advanced Aero-Engine Science and Technology on Altitude Simulation Laboratory

To solve the problem of robust servo performance of Flight Environment Testbed(FET)of Altitude Ground Test Facilities(AGTF) over the whole operational envelope, a two-degree-offreedom μ synthesis method based on linear Parameter Varying(LPV) schematic is proposed, and meanwhile a new structure frame of μ synthesis control on two degrees of freedom with double integral and weighting functions is presented, which constitutes a core support part of the paper. Aimed at the problem of reference command's rapid change, one freedom feed forward is adopted, while another freedom output feedback is used to meet good servo tracking as well as disturbance and noise rejection; furthermore, to overcome the overshoot problem and acquire dynamic tuning,the integral is introduced in inner loop, and another integral controller is used in outer loop in order to guarantee steady errors; additionally, two performance weighting functions are designed to achieve robust specialty and control energy limit considering the uncertainties in system. As the schedule parameters change over large flight envelope, the stability of closed-loop LPV system is proved using Lyapunov inequalities. The simulation results show that the relative tracking errors of temperature and pressure are less than 0.5% with LPV μ synthesis controller. Meanwhile, compared with non-LPV μ synthesis controller in large uncertainty range, the proposed approach in this research can ensure robust servo performance of FET over the whole operational envelope.

关键词： Altitude ground test facilities Flight environment testbed linear parameter varying Robust control Two-degree-of-freedom μ Synthesis

Review of Soft linear Actuator and the Design of a Dielectric Elastomer linear Actuator

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Acta Mechanica Solida Sinica 2019年第5期32卷 566-579页

作者： Xunuo Cao Mingqi Zhang Zhen Zhang Yi Xu Youhua Xiao Tiefeng Li Department of Engineering Mechanics Zhejiang University38 Zheda RoadHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang UniversityHangzhou 310027China Department of Engineering Mechanics Northwestern Polytechnical UniversityDong Xiang Road 1XVan 710129China Department of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027China

Natural muscle provides excellent motilities for animals.As the basic unit of the muscle system,the skeletal muscle fibers function as a soft linear actuator.Inspired by the muscle fibers,researchers have developed various soft active devices with linear actuation.This paper reviews several soft linear actu ators,such as the dielec trie elastomer,t hermal responsive hydrogels,pneumatic artificial muscle,and conducting polymers.The actuation mechanisms and performances of these soft linear actuators are summarized.Based on the dielectric elastomer,we propose a design of a hybrid system with linear actuation,driven by both the electric motor and dielectric elasto mer cone.The elec tromechanical behaviors of the dielec trie elastomer cone have been investigated in both experiment and finite element analysis.This work may guide the further design of soft actuators and robots.

关键词： Soft linear actu at or Dielectric elast omer Finite element analysis

Direct position determination using single moving rotating linear array: Noncoherent and coherent processing

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Chinese Journal of Aeronautics 2020年第2期33卷 688-700页

作者： Guizhou WU Min ZHANG Chaoxin HE Fucheng GUO State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System National University of Defense TechnologyChangsha 410073China

To improve the resolution and accuracy of Direct Position Determination(DPD),this paper investigates the problem of positioning multiple emitters directly with a single moving Rotating linear Array(RLA).Firstly,the geometry of the RLA is formulated and analysed.According to its geometry,the intercepted noncoherent signals in multiple interception intervals are modeled.Correspondingly,the Multiple SIgnal Classification(MUSIC)based noncoherent DPD approach is proposed.Secondly,the synchronous coherent pulse signals are individually considered and formulated.And the coherent DPD approach which aims for localizing this special type of signal is presented by stacking all array responses at different interception intervals.Besides,we also derive the constrained Cramer-Rao Lower Bound(CRLB)expression for both noncoherent and coherent DPD with RLA under the constraint that the altitudes of the emitters are known.At last,computer simulations are included to examine the performance of the proposed approach.The results demonstrate that the localization accuracy and resolution of DPD with single moving linear array can be significantly improved by the array rotation.In addition,coherent DPD with RLA further improves the resolution and increases the maximum emitter number that can be localized compared with the noncoherent DPD with RLA.

关键词： Coherent signal processing Constrained Cramer-Rao lower bound Direct position determination Multiple signal classification Resolution Rotating linear array