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Trial application of the envelope method to the potential ambiguity problem
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作者 Li-Yuan Hu Yu-Shou Song 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期73-80,共8页
The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and f... The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering components.By contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,respectively.Hence,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity problem.In this study,we conducted a trial application of the envelope method to the potential ambiguity problem.The envelope method was improved by including uncertainties in the experimental data.The colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the analyses.For each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is refractive.The calculated angular distributions were decomposed into nearside and farside scattering components.Using the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside components.The capability of the envelope method to analyze the potential ambiguities was also discussed. 展开更多
关键词 Elastic scattering Optical potential ambiguities envelope method Nearside/farside decomposition
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A Semi-Analytical Method for the PDFs of A Ship Rolling in Random Oblique Waves 被引量:2
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作者 LIU Li-qin LIU Ya-liu +2 位作者 XU Wan-hai LI Yan TANG You-gang 《China Ocean Engineering》 SCIE EI CSCD 2018年第1期74-84,共11页
The PDFs(probability density functions) and probability of a ship rolling under the random parametric and forced excitations were studied by a semi-analytical method. The rolling motion equation of the ship in random ... The PDFs(probability density functions) and probability of a ship rolling under the random parametric and forced excitations were studied by a semi-analytical method. The rolling motion equation of the ship in random oblique waves was established. The righting arm obtained by the numerical simulation was approximately fitted by an analytical function. The irregular waves were decomposed into two Gauss stationary random processes, and the CARMA(2, 1) model was used to fit the spectral density function of parametric and forced excitations. The stochastic energy envelope averaging method was used to solve the PDFs and the probability. The validity of the semi-analytical method was verified by the Monte Carlo method. The C11 ship was taken as an example, and the influences of the system parameters on the PDFs and probability were analyzed. The results show that the probability of ship rolling is affected by the characteristic wave height, wave length, and the heading angle. In order to provide proper advice for the ship’s manoeuvring, the parametric excitations should be considered appropriately when the ship navigates in the oblique seas. 展开更多
关键词 ship random rolling parametric and forced excitations stochastic energy envelope averaging method probability density function parameter influence analysis
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Multislice behavioral modeling based on envelope domain for power amplifiers
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作者 Wang Huadong Bao Jingfu Wu Zhengde 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期274-277,共4页
An envelope domain multislice behavioral modeling is introduced. The tradition AM-AM and AM- PM characteristics of power amplifiers axe extended to envelope domain and base-band filter is applied to distortion complex... An envelope domain multislice behavioral modeling is introduced. The tradition AM-AM and AM- PM characteristics of power amplifiers axe extended to envelope domain and base-band filter is applied to distortion complex envelope signal for description of the envelope memory effect. Using traditional one and two-tone tests, the coefficients of nonlinear model and the FIR filter can be extracted. At last the model has been applied to a 10 W WCDMA Power amplifier to predict its output signal. And simulation results show that the model output conforms very well to the traditional transistor level simulation results. 展开更多
关键词 behavioral modeling envelope method power amplifiers
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Three-dimensional FDEM numerical simulation of failure processes observed in Opalinus Clay laboratory samples 被引量:10
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作者 Omid Mahabadi Patrick Kaifosh +1 位作者 Paul Marschall Tim Vietor 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第6期591-606,共16页
This study presents the first step of a research project that aims at using a three-dimensional (3D) hybridfinite-discrete element method (FDEM) to investigate the development of an excavation damaged zone(EDZ) ... This study presents the first step of a research project that aims at using a three-dimensional (3D) hybridfinite-discrete element method (FDEM) to investigate the development of an excavation damaged zone(EDZ) around tunnels in a clay shale formation known as Opalinus Clay. The 3D FDEM was first calibratedagainst standard laboratory experiments, including Brazilian disc test and uniaxial compression test. Theeffect of increasing confining pressure on the mechanical response and fracture propagation of the rockwas quantified under triaxial compression tests. Polyaxial (or true triaxial) simulations highlighted theeffect of the intermediate principal stress (s2) on fracture directions in the model: as the intermediateprincipal stress increased, fractures tended to align in the direction parallel to the plane defined by themajor and intermediate principal stresses. The peak strength was also shown to vary with changing s2. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved. 展开更多
关键词 Three-dimensional(3D) hybrid finitediscrete element method(FDEM) Intermediate principal stress Discrete element methods True triaxial behaviour Failure envelope
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A BRANCH BOUND METHOD FOR SUBSET SUM PROBLEM 被引量:1
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作者 吴士泉 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1994年第3期302-314,共13页
This paper indicates the possible difficulties for applying the interior point method to NPcomplete problems,transforms an NP-complete problem into a nonconvex quadratic program and then develops some convexity theori... This paper indicates the possible difficulties for applying the interior point method to NPcomplete problems,transforms an NP-complete problem into a nonconvex quadratic program and then develops some convexity theories for it. Lastly it proposes an algorithm which uses Karmarkar's algorithm as a subroutine. The finite convergence of this algorithm is also proved. 展开更多
关键词 Subset sum problem nonconvex quadratic program convex envelope interior point method
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Zinc tin oxide thin films prepared by MOCVD with different Sn/Zn ratios
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作者 Ying Xu Lin-Yan Hou Xiao-Meng Zhang 《Rare Metals》 SCIE EI CAS CSCD 2017年第9期753-757,共5页
Zinc tin oxide(ZTO) thin films, with zinc acetate and tributyltin chloride as raw materials, were deposited on glass substrates by the method of metal organic chemical vapor deposition(MOCVD). The crystallization,... Zinc tin oxide(ZTO) thin films, with zinc acetate and tributyltin chloride as raw materials, were deposited on glass substrates by the method of metal organic chemical vapor deposition(MOCVD). The crystallization, microstructure and optical properties were investigated by scanning electronic microscope(SEM),X-ray diffraction(XRD) and ultraviolet-visible(UV-Vis)spectrophotometer. The results show that with the increase in Sn/Zn ratio, the crystal changes from wurtzite to rutile phase. When the ratio reaches 11:18,the intensity of Zn2SnO4 peaks appears to be the strongest and the optical band gap is about 3.27 eV. Calculated by the envelope method, the thickness of the ZTO thin films is 713.24 nm.Measured by UV-Vis spectrophotometer, the transmittance of the ZTO thin films reaches up to 80% in the wavelength range of 400-1000 nm when the Sn/Zn ratio is 7:18. 展开更多
关键词 Sn/Zn ratio MOCVD ZTO thin films envelope method Optical properties
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Overlapped groupwise dimension reduction
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作者 ZHOU JingKe WU JianRong ZHU LiXing 《Science China Mathematics》 SCIE CSCD 2016年第12期2543-2560,共18页
Existing groupwise dimension reduction requires given group structure to be non-overlapped. This confines its application scope. We aim at groupwise dimension reduction with overlapped group structure or even unknown ... Existing groupwise dimension reduction requires given group structure to be non-overlapped. This confines its application scope. We aim at groupwise dimension reduction with overlapped group structure or even unknown group structure. To this end, existing groupwise dimension reduction concept is extended to be compatible with overlapped group structure. Then, the envelope method is ameliorated to deal with overlapped groupwise dimension reduction. As an application, Gaussian graphic model is employed to estimate the structure between predictors when the group structure is not given, and the amended envelope method is used for groupwise dimension reduction with graphic structure. Furthermore, the rationale of the proposed estimation procedure is explained at the population level and the estimation consistency is proved at the sample level. Finally, the finite sample performance of the proposed methods is examined via numerical simulations and a body fat data analysis. 展开更多
关键词 sufficient dimension reduction groupwise dimension reduction overlapped group structure envelope method Gaussian graphic model
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