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New Explorations on Cannon's Contributions and Generalized Solutions for Uniform Linear Motion Blur Identification

Journal of Computer Science & Technology 2012年第1期27卷 174-186页

作者： Lu Wang Hong-Yan Zhang Si-Long Peng The National Engineering and Technology Research Center for ASIC Design Institute of AutomationChinese Academy of SciencesBeijing 100190China The Key Laboratory of Complex Systems and Intelligence Science Institute of AutomationChinese Academy of Sciences Beijing 100190China Sino-European institute of aviation Engineering Civil Aviation University of ChinaTianjin 300300China

Existing frequency-domain-oriented methods of parameter identification for uniform linear motion blur （ULMB） images usually dealt with special scenarios. For example, blur-kernel directions were horizontal or vertical, or degraded images were of foursquare dimension. This excludes those identification methods from being applied to real images, especially to estimate undersized or oversized blur kernels. Pointing against the limitations of blur-kernel identifications, discrete Fourier transform （DFT）-based blur-kernel estimation methods are proposed in this paper. We analyze in depth the Fourier frequency response of generalized ULMB kernels, demonstrate in detail its related phase form and properties thereof, and put forward the concept of quasi-cepstrum. On this basis, methods of estimating ULMB-kernel parameters using amplitude spectrum and quasi-cepstrum are presented, respectively. The quasi-cepstrum-oriented approach increases the identifiable blur-kernel length, up to a maximum of half the diagonal length of the image. Meanwhile, directing toward the image of undersized ULMB, an improved method based on quasi-cepstrum is presented, which ameliorates the identification quality of undersized ULMB kernels. The quasi-cepstrum-oriented approach popularizes and applies the simulation-experiment- focused DFT theory to the estimation of real ULMB images. Compared against the amplitude-spectrum-oriented method, the quasi-cepstrum-oriented approach is more convenient and robust, with lower identification errors and of better noiseimmunity.

关键词： Fourier amplitude spectrum phase perpendicular relation uniform linear motion blur identification quasicepstrum

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Higgs Algebraic Symmetry of Screened System in a Spherical Geometry

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Communications in Theoretical Physics 2013年第9期60卷 278-282页

作者：李艳张福林谷瑞娟陈景灵 Theoretical Physics Division Chern Institute of MathematicsNankai University Centre for Quantum Technologies National University of Singapore Physics Department School of ScienceTianjin University Sino-European institute of aviation Engineering Civil Aviation University of China

The orbits and the dynamical symmetries for the screened Coulomb potentials and isotropic harmonic oscillators have been studied by Wu and Zeng [Z.B. Wund J.Y. Zeng, Phys. Rev. A 62 （2000） 032509]. We find similar properties in the corresponding systems in a sphericM space, whose dynamical symmetries are described by Higgs algebra. There exist extended Runge-Lenz vector for screened Coulomb potentials and extended quadruple tensor for screened harmonic oscillators. They, together with angular momentum, constitute the generators of the geometrical symmetry group. Moreover, there exist an infinite number of dosed orbits for suitable angular momentum values, and we give the equations of the classical orbits. The eigenenergy spectrum and corresponding eigenstates in these systems are derived.

关键词： dynamical symmetry Higgs algebraic screened system spherical geometry

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Mathematical simulation of low cycle fatigue of high-loaded engine parts

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Propulsion and Power Research 2018年第4期7卷 277-287页

作者： Yury M.Temis Central institute of aviation Motors 2 Aviamotornaya st.Moscow 111116Russia

The paper discusses main aspects of low cycle fatigue influence on the lifetime ofengine *** importance and history of the problem,the main experiments and the effectsimpacting the low cycle fatigue of structural materials are described.A hypothesis about theexistence of a thermomechanical surface of structural material,generalized to the case of acyclical loading was used to approximate the loops of cyclic nonisothermal elastoplasticdeformation *** cyclic deformation curve model is based on the following threeparameters:the elastic modulus during unloading,the Bauschinger effect and the conversionparameter of the nonlinear part of its first *** model also accounts for theaccumulated plastic strain,as well as the testing *** criterion of durability isformulated,based on the dependence between the number of halfcycles to failure and theaccumulated plastic *** theory of plasticity,generalized to the case ofcyclic deformation,in combination with the durability model and technology of"dying"elements is applied to the finite element analysis of low cycle fatigue of gas turbine *** results of calculations are demonstrated.

关键词： Gas turbine engine Low cycle fatigue Nonisothermal plasticity Finite element modeling Durability modeling Cyclic loading

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New Clustering Method in High-Di mensional Space Based on Hypergraph-Models

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Journal of Beijing institute of Technology 2006年第2期15卷 156-161页

作者：陈建斌王淑静宋瀚涛 School of Computer Science and Technology Beijing Institute of Technology China aviation Accounting Center

To overcome the limitation of the traditional clustering algorithms which fail to produce meaningful clusters in high-dimensional, sparseness and binary value data sets, a new method based on hypergraph model is proposed. The hypergraph model maps the relationship present in the original data in high dimensional space into a hypergraph. A hyperedge represents the similarity of attrlbute-value distribution between two points. A hypergraph partitioning algorithm is used to find a partitioning of the vertices such that the corresponding data items in each partition are highly related and the weight of the hyperedges cut by the partitioning is minimized. The quality of the clustering result can be evaluated by applying the intra-cluster singularity value. Analysis and experimental results have demonstrated that this approach is applicable and effective in wide ranging scheme.

关键词： high-dimensional clustering hypergraph model data mining

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HIGH-ORDER AR ESTIMATION METHOD OF ARMA POWER SPECTRUM

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Journal of Electronics(China) 1987年第4期4卷 299-304页

作者：余辉里 Research institute No.634 Ministry of aviation Industry

In this paper,the high-order AR estimation method of ARMA power spectrum and the whitened-noisedecision order criterion of AR order are *** is indicated that the quality of hlgh-order ARestimation is related to the ill-conditlon problem and the algorithmic stability of numerical calculation in *** latter can be solved well by using the recurrence algorithm of Householder transform in thesolution of high-order AR parameter estimation

关键词： ARMA der HIGH-ORDER AR ESTIMATION METHOD OF ARMA POWER SPECTRUM

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Investigation of the usefulness of zaleplon at two doses to induce afternoon-sleep under noise interference and its effects on psychomotor performance and vestibular function

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Journal of Medical Colleges of PLA(China) 2016年第1期31卷 28-33页

作者： Liang-En Chen An-Dong Zhao Qing-Jun Zhang Feng Wu Zhao-Li Ge Hua Ge Hao Zhan Department of Pharmacology Institute of Aviation MedicineAir Force

Background:Military operation personnel often suffer from sleep difficulty because of their work *** this study,we investigated the efficacy of zaleplon at two doses to induce afternoon-sleep under noise interference and its effects on psychomotor performance and vestibular function; we subsequently established the optimal dosage regimen for military operation ***:Twenty-two healthy young male volunteers were recruited for the *** subjects took 10 mg or 15 mg of zaleplon and placebo alternately and then were exposed to *** in polysomnography(PSG) indices,including sleep latency(SL),sleep efficiency(SE) and sleep structure,were recorded after drug *** awakening,the volunteers' subjective judgments of sleep quality and sleepiness were *** volunteers underwent 3 psychomotor performance tests at a one-week interval,and the psychomotor performance tests were conducted before and after taking zaleplon and *** volunteers participated in the vestibular function test session,and parameters,including optokinetic nystagmus(OKN),vestibular ocular reflex(VOR),visualvestibular ocular reflex(VVOR) and vestibular ocular reflex fixation suppression(VOR-Fix),were detected by the same experimental design as described *** data of sleep observations were subjected to one-way variance ***:Compared with the placebo group,SL was shortened significantly,and the scores of subjective sleep quality and sleep depth were clearly increased in the zaleplon 10 mg group(P<0.05).Moreover,the SE and the percent of REM(rapid eye movement) sleep were increased remarkably in the zaleplon 15 mg group(P<0.01).Furthermore,the SE,percent of REM sleep and scores of subjective sleep depth in the zaleplon 15 mg group were significantly higher than in the zaleplon 10 mg group(P<0.05).The psychomotor performance did not change significantly after ingestion of 10 mg or 15 mg of zaleplon,whereas the OKN and VOR gains

关键词： Insomnia Sleep Hypnotic Zaleplon Psychomotor performance Vestibular function

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CONJUGATE MODEL FOR HEAT AND MASS TRANSFER OF POROUS WALL IN THE HIGH TEMPERATURE GAS FLOW

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Acta Mechanica Sinica 2001年第3期17卷 245-250页

作者： A.F.Polyakov D. L. Reviznikov 沈青唐锦荣魏叔如 institute of High Temperatures Russian Academy of Sciences Moscow Russia Moscow aviation institute (Technical University) Moscow Russia LHD Institute of Mechanics Chinese Academy of Science Beijing China 100080

Heat and mass transfer of a porous permeable wall in a high temperature gas dynamical flow is considered. Numerical simulation is conducted on the ground of the conjugate mathematical model which includes filtration and heat transfer equations in a porous body and boundary layer equations on its surface. Such an approach enables one to take into account complex interaction between heat and mass transfer in the gasdynamical flow and in the structure subjected to this flow. The main attention is given to the impact of the intraporous heat transfer intensity on the transpiration cooling efficiency.

关键词： heat and mass transfer porous media conjugate model high temperature gas flow

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Optimizing combination of aircraft maintenance tasks by adaptive genetic algorithm based on cluster search

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Journal of Systems Engineering and Electronics 2016年第1期27卷 140-156页

作者： Huaiyuan Li Hongfu Zuo Kun Liang Juan Xu Jing Cai Junqiang Liu College of Civil aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China Huaiyin institute of Technology Huai'an 223003China

It is significant to combine multiple tasks into an optimal work package in decision-making of aircraft maintenance to reduce cost,so a cost rate model of combinatorial maintenance is an urgent ***,the optimal combination under various constraints not only involves numerical calculations but also is an NP-hard combinatorial *** solve the problem,an adaptive genetic algorithm based on cluster search,which is divided into two phases,is put *** the first phase,according to the density,all individuals can be homogeneously scattered over the whole solution space through crossover and mutation and better individuals are collected as candidate cluster *** the second phase,the search is confined to the neighbourhood of some selected possible solutions to accurately solve with cluster radius decreasing slowly,meanwhile all clusters continuously move to better regions until all the peaks in the question space is *** algorithm can efficiently solve the combination *** the optimization on decision-making of aircraft maintenance by the algorithm for an example,maintenance which combines multiple parts or tasks can significantly enhance economic benefit when the halt cost is rather high.

关键词： cluster search genetic algorithm combinatorial optimization multi-part maintenance grouping maintenance.

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Typical adaptive neural control for hypersonic vehicle based on higher-order filters

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Journal of Systems Engineering and Electronics 2020年第5期31卷 1031-1040页

作者： ZHAO Hewei LI Rui Shore Guard institute Naval Aviation UniversityYantai 264001China Wenjing College Yantai UniversityYantai 264005China

A typical adaptive neural control methodology is used for the rigid body model of the hypersonic vehicle. The rigid body model is divided into the altitude subsystem and the velocity subsystem. The proportional integral differential(PID) controller is introduced to control the velocity track. The backstepping design is applied for constructing the controllers for the altitude *** avoid the explosion of differentiation from backstepping, the higher-order filter dynamic is used for replacing the virtual controller in the backstepping design steps. In the design procedure,the radial basis function(RBF) neural network is investigated to approximate the unknown nonlinear functions in the system dynamic of the hypersonic vehicle. The simulations show the effectiveness of the design method.

关键词： hypersonic vehicle adaptive neural control higher-order filter differential explosion

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Repair tolerance assessment for aircraft composite structures using Bayesian updating

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Chinese Journal of Aeronautics 2024年第6期37卷 360-391页

作者： Xin LI Hongfu ZUO Bin YANG School of Automotive and Rail Transit Nanjing Institute of TechnologyNanjing 211167China Civil aviation Key Laboratory of Aircraft Health Monitoring and Intelligent Maintenance College of Civil AviationNanjing University of Aeronautics and AstronauticsNanjing 211106China

Detection and repair of composite damage is crucial to ensure the safety and reliability of aircraft structures.A novel approach to quantitatively evaluate the repair tolerance of composite structures in civil aircraft based on Bayesian updating is *** method incorporates historical damage inspection data to determine the prior distribution of damage size,which is then updated with newly collected damage size data using Bayesian *** Carlo simulation is employed to investigate the probability of failure and estimate maintenance costs,considering various factors such as the frequency and timing of damage events,damage detection,structural strength,gust loads,and maintenance expenses throughout the lifecycle of composite *** and economic factors are considered to establish a lower threshold for repairs and an upper threshold for maintenance based on the occurrence of accidental impact *** of the effectiveness and feasibility of a quantitative assessment method for repair tolerance is conducted using damage statistics data from civil aircraft routes utilizing the structural skin panels of composite outer *** results demonstrate that the method proposed in conjunction with extensive simulations and full utilization of field damage inspection data can effectively simulate unexpected impact damage situations that may occur during civil aircraft service and evaluate the reliability and economic feasibility of the repair of *** research findings hold significant theoretical and practical value for the preparation of documents for continued airworthiness of composite structures,including structural repair manuals and maintenance programs.

关键词： Composite structures Repair tolerance Maintenance Bayesian updating Probability of failure

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