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High Technology Letters 1995年第1期1卷 102-104页

作者： Xiaowen, z.. Xueping, L. Yuan, L. Xurui, X. Songbin, z.. z.ngju, X. yinghua, z. Academia Sinica Beijing China

Ultrafine PbS particles with different siz.s have been prepared in perfluorocarboxylated cation-exchanged films. The variation of PbS particle siz. was clarified by absorption spectra and TEM graphs. Time-resolved optical Kerr effects were measured by femtosecond pump-probe techniques. Optical Kerr effect response time was estimated to be less than 165 fs. A third-order optical nonlinearity of χ(3)10-12 esu for PbS particles was obtained and it was found that it increases with the decrease of particle siz.s, showing the influence of quantum confined effect on optical nonlinear behaviour of ultrafine particles.

关键词： PbS Ultrafine particle Optical nonlinearity Optical Kerr effect

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青年亚文化流行语的观察及审思

新闻与传播评论 2025年第1期78卷 80-88页

作者：李英华太原学院教育系山西太原030032

躺平、摆烂等展现青年精神状态的亚文化流行语风格相似且接续流行多年,对这一现象进行历时性思考,有助于深入探寻社会变迁背景下青年心理的时代特征。立足社会生态系统理论,运用深度访谈法进行分析后发现:流行语接续流行之原因可提炼为... 详细信息

躺平、摆烂等展现青年精神状态的亚文化流行语风格相似且接续流行多年,对这一现象进行历时性思考,有助于深入探寻社会变迁背景下青年心理的时代特征。立足社会生态系统理论,运用深度访谈法进行分析后发现:流行语接续流行之原因可提炼为三种“非常之势”,分别是非主流的话语生产、非自觉的自我和解、非传统的自我表达。整体而言,这是社会生态系统中“宏系统”与“历时系统”共同作用的结果,二者分别侧重空间与时间因素。宏系统主要产生文化方面的影响,包括精神文化(具有反常特质的亚文化接续实践)与制度文化(加速时代的结构性困境);历时系统的影响则指向社会变迁(中国式现代化之进程)。流行语之共性及其折射出的青年心理并非既有研究普遍认为的“颓丧”,而是具有戏谑夸张意味的“松弛感”,这源于当代青年自我建构的积极变化,是中国式现代化在人格发展上的生动表达。文章主张以“时空双维”之视角观照亚文化、解析“真青年”,一定程度上丰富了亚文化的研究范式。

关键词：亚文化流行语历时性视角自我建构现代人格 z.代青年

Base force element method of complementary energy principle for large rotation problems

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Acta Mechanica Sinica 2009年第4期25卷 507-515页

作者： Yijiang Peng yinghua Liu FML Department of Engineering Mechanics Tsinghua University 100084 Beijing China Key Lab of Urban Security and Disaster Engineering Beijing University of Technology 100124 Beijing China

Using the concept of the base forces, a new finite element method （base force element method, BFEM） based on the complementary energy principle is presented for accurate modeling of structures with large displacements and large rotations. First, the complementary energy of an element is described by taking the base forces as state variables, and is then separated into deformation and rotation parts for the case of large deformation. Second, the control equations of the BFEM based on the complementary energy principle are derived using the Lagrange multiplier method. Nonlinear procedure of the BFEM is then developed. Finally, several examples are analyz.d to illustrate the reliability and accuracy of the BFEM.

关键词： Base force element method (BFEM) Complementary energy principle Lagrange multiplier method Geometrically nonlinear Large rotation

RUIN PROBABILITIES WITH PAIRWISE QUASI-ASYMPTOTICALLY INDEPENDENT AND DOMINATEDLY-VARYING TAILED CLAIMS

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Journal of Systems Science & Complexity 2012年第2期25卷 303-314页

作者： yinghua DONG Yuebao WANG Department of Mathematics Soochow University College of Mathematics and Statistics Nanjing University of Information Science and Technology

This paper considers the nonstandard renewal risk model in which a part of surplus is invested into a Black-Scholes market whose price process is modelled by a geometric Brownian motion, claim siz.s form a sequence of not necessarily identically distributed and pairwise quasi-asymptotically independent random variables with dominatedly-varying *** authors obtain a weakly asymptotic formula for the finite-time and infinite-time ruin *** particular,if the claims are identically distributed and consistently-varying tailed,then an asymptotic formula is presented.

关键词： Dominatedly varying tails nonstandard renewal risk model pairwise quasi-asymptotic independence perturbed renewal risk model weighted renewal function.

Periods on the Cascade Connection of an LFSR and an NFSR

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Chinese Journal of Electronics 2019年第2期28卷 301-308页

作者： YANG yinghua z.NG Xiangyong XU Yunge Hubei Key Laboratory of Applied Mathematics Hubei University

We study the periods of sequences produced by the cascade connection of two Feedback shift registers（FSRs）. The period of the cascade connection is the period of the longest sequences it produces. An upper bound for the period of the cascade connection of a Nonlinear feedback shift register（NFSR） into a Linear feedback shift register（LFSR） is established. In addition,the cascade connection of an n-stage maximum-length LFSR into an n-stage NFSR is called an（n + n）-stage Grain-like NFSR, and we propose two families of（n + n）-stage Grain-like NFSRs such that the minimal period 2~n-1 is achievable for a positive integer n.

关键词： Stream cipher Cascade connection Grain-like NFSR Period

Base force element method (BFEM) on complementary energy principle for linear elasticity problem

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2025-2032页

作者： LIU yinghua PENG YiJiang Applied Mechanics Laboratory Department of Engineering Mechanics Tsinghua University Beijing 100084 China Key Lab of Urban Security ＆ Disaster Engineering Department of Civil Engineering Beijing University of Technology Beijing 100124 China

Using the concept of base forces as state variables,a new finite element method-the base force element method (BFEM) on complementary energy principle for linear elasticity problems is ***,an explicit expression of compliance matrix for an element is derived through base forces by dyadic ***,the explicit control equations of finite element method of complementary energy principle are derived using Lagrange multiplier ***,the base forces element procedure for linear elasticity is ***,several examples are analyz.d to illustrate the reliability and accuracy of the formulation and the procedure.

关键词： base forces elasticity problem complementary energy principle finite element method base force element method,Lagrange multiplier method compliance matrix

Effects of coal seam dip angle on the outburst in coal roadway excavation

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International Journal of Mining Science and Technology 2019年第5期29卷 757-764页

作者： Cheng Hou yinghua z.ang Yi Yan University of Science and Technology Beijing Beijing 100083China Department of Mechanical Engineering McGill UniversityMontrealQC H3A 0C3Canada

The prevention and forecast of coal and gas outburst has always been one of the key issues in coal mining *** simulating the process of tunneling in coal seam with different dip angle through FLAC3D software,the dangerous z.ne in which outburst may occur and the probability of outburst near the working face were predicted through the distribution of stress,displacement and plastic *** we discussed the siz. of unstable area in the surrounding rock through the distribution of stress and the variation curve of the displacement on the roadway *** results show that,with an increase of the coal seam dip angle,the risk of outburst in the working face rises *** the dangerous areas in which may outburst occur moves to the upper part of coal *** siz. of unstable area in the surrounding rock increases with the increase of coal seam dip angle.

关键词： Dip angle Stress concentration Plastic z.ne Displacement Coal and gas outburst

Structural dynamic responses of a stripped solar sail subjected to solar radiation pressure

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Chinese Journal of Aeronautics 2020年第8期33卷 2204-2211页

作者： Junhui z.ANG Na WU An TONG yinghua LIU School of Civil Engineering North China University of TechnologyBeijing 100144China School of Aerospace Engineering Tsinghua UniversityBeijing 100144China

The stripped solar sail whose membrane is divided into separate narrow membrane strips is believed to have the best structural *** this paper,the stripped solar sail structure is regarded as an assembly made by connecting a number of boom-strip components in *** the coupling effects between booms and membrane strips,an exact and semianalytical method to calculate structural dynamic responses of the stripped solar sail subjected to solar radiation pressure is *** case study of a 100 m stripped solar sail shows that the stripped architecture helps to reduce the static deflections and amplitudes of the steady-state dynamic *** prestress of the membrane strips will decrease stiffness of the sail and increase amplitudes of the steady-state dynamic *** thickness of the boom will benefit to stability of the sail and reduce the resonant *** proposed semi-analytical method provides an efficient analysis tool for structure design and attitude control of the stripped solar sail.

关键词： Distributed transfer function method Frequency response Solar radiation pressure Solar sail Structural dynamic response

Joint Empirical Likelihood Confidence Regions for a Finite Number of Quantiles Under Negatively Associated Samples

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Journal of Systems Science & Complexity 2015年第6期28卷 1389-1398页

作者： QIN Yongsong LI yinghua LEI Qingz.u Department of Mathematics Guangxi Normal University

In this paper, the authors obtain the joint empirical likelihood confidence regions for a finite number of quantiles under negatively associated samples. As an application of this result, the empirical likelihood conf... 详细信息

关键词： Blockwise empirical likelihood confidence region negatively associated sample quantile

OPTICAL FIELD INDUCED REFRACTIVE INDEX CHANGE DUE TO COLLISION-ENHANCED z.EMAN COHERENCE

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Chinese Physics Letters 1990年第1期7卷 9-11页

作者： z.u yinghua YANG Yang Department of Physics Peking UniversityBeijing 100871

The collision-enhanced z.eman coherence ρ_((ω1-ω2))^((2)) has been demonstrated by the effect of optical field induced index of refraction change,which is described by the real part of the nonlinear susceptibility χ_((-ω1,ω1-ω2,ω2))^((3)).The experiments are performed in sodium vapor by a Mach-z.hnder *** dependences of the effect on the magnetic field,pump beam intensity,and Ar pressure are consistent with the theory.

关键词： interferometer pump effect