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    题名 作者 年代 出处 被引量
1Anti-plane deformations around arbitrary-shaped canyons on a wedge-shape half-space:moment method solutions显示文摘The wave propagation behavior in an elastic wedge-shaped medium with an arbitrary shaped cylindrical canyon at its vertex has been studied. Nunerical computation of the wave displacement field is carried out on and near the canyon surfaces using weighted-residuals (moment method). The wave displacement fields are computed by the residual mcthod for the cases of elliptic, circular, rounded-rectangular and flat-elliptic canyons. The analysis demonstrates that thc resulting surface displacemcnt depends, as in similar previous analyses, on several factors including, but not limited, to the angle of thc wedge, thc geometry of thc vertex, the frcquencies of thc incident waves, the angles of incidence, and the material properties of the media. The analysis provides intriguing results that help to explain geophysical observations regarding the amplification of seismic energy as a function of site conditions.Nazaret Dermendjian Vincent W.Lee 梁建文 2003Earthquake Engineering and Engineering Vibration2003,2,2:19
2Periodic and chaotic dynamics of composite laminated piezoelectric rectangular plate with one-to-two internal resonance显示文摘The bifurcations and chaotic dynamics of a simply supported symmetric cross-ply composite lami- nated piezoelectric rectangular plate are studied for the first time, which are simultaneously forced by the transverse, in-plane excitations and the excitation loaded by piezoelectric layers. Based on the Reddy’s third-order shear deformation plate theory, the nonlinear governing equations of motion for the composite laminated piezoelectric rectangular plate are derived by using the Hamilton’s principle. The Galerkin’s approach is used to discretize partial differential governing equations to a two-degree- of-freedom nonlinear system under combined the parametric and external excitations. The method of multiple scales is employed to obtain the four-dimensional averaged equation. Numerical method is utilized to find the periodic and chaotic responses of the composite laminated piezoelectric rectangular plate. The numerical results indicate the existence of the periodic and chaotic responses in the aver- aged equation. The influence of the transverse, in-plane and piezoelectric excitations on the bifurca- tions and chaotic behaviors of the composite laminated piezoelectric rectangular plate is investigated numerically.ZHANG Wei YAO ZhiGang YAO MingHui 2009Science China(Technological Sciences)2009,52,3:11
3A review on application of composite truss bridges composed of hollow structural section members显示文摘Composite truss with hollow structural section(HSS) members is deemed as the structure applicable to large-span and heavily-loaded bridges. To promote the application of composite truss bridge with HSS members in China, this paper described its structural characteristics and technology in details. Besides, not only were 32 typical design cases of composite truss bridges with HSS members collected, but also the corresponding historical development was summed up. Comparisons on structural components, characteristics and engineering applications were made among composite truss bridges with HSS members in different structural forms. Then, the analysis on the characteristics of composite truss bridges with concrete-filled steel tubular(CFST) chords was conducted, and the challenges on the aspects of complicated joints and interfacial debonding were pointed out. To address these problems, the concrete-filled rectangular hollow section(CFRHS)stiffened with PBLs(Perfobond Ribs) was proposed to improve the reliability of confinement effect in CFST member and force transfer in joints. The advantages on the mechanical properties of CFRHS structure stiffened using PBLs were systematically expounded with respect to the behaviors of steel plate, interface, member and joint. Moreover, the structure design, construction technology, structural calculation and economic efficiency of the practical bridge with CFRHS chords stiffened using PBLs were comprehensively analyzed.The results demonstrated that composite truss bridge with PBL-stiffened CFRHS members was competitive in mechanical performance and construction.Zhijuan Tian Yongjian Liu Lei Jiang Weiqing Zhu Yinping Ma 2019Journal of Traffic and Transportation Engineering(English Edition)2019,6,1:11
4Dynamics analysis and experiment on the fishtailing type of valveless piezoelectric pump with rectangular vibrator显示文摘In recent years, the research and development of piezoelectric pumps have become an increasingly popular topic. Minimization, structure simplification and stronger output become the focus of piezoelectric pumps’ research due to its possible application in MEMS technology. The valveless fishtailing piezoelectric pump, neither a volumetric nor a rotating pump, was invented according to the bionics of fish swimming. With assumption that the head of the fish is fixed while its tail is swinging, fluid would flow toward the end of the tail, achieving the function of a valveless pump. This type of pumps creates a new branch for the piezoelectric pump research, which is proposed for the first time in this paper. The relationship between the flow rates and vibrating frequencies was derived from the interaction between the vibrator and fluid. Numerical simulations with FEM software were conducted to study the first and second vibration modes of the piezoelectric vibrator. The results showed that the maximum amplitude of the vibrator was 0.9 mm at the frequency of 76 Hz for the first vibration mode, while the maximum amplitude of the vibrator was 0.22 mm at the frequency of 781 Hz for the second vibration mode. Experiments were conducted with the Doppler laser vibration measurement system, and the results were compared to those of the FEM simulation. It was shown that in the first vibration mode the piezoelectric vibrator reached its maximum amplitude of about 0.9 mm at the driving frequency of 49 Hz, which gives the flow rate of 2.0 mL/min, in the second vibration mode, the maximum amplitude was about 0.25 mm at the frequency of 460 Hz with the flow rate being 6.4 mL/min.HUANG Yi1, ZHANG JianHui1, HU XiaoQi1, XIA QiXiao2, HUANG WeiQing1 & ZHAO ChunSheng1 1 Department of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China 2 Department of Mechanical and Electrical Engineering, Beijing Union University, Beijing 100020, China 2010Science China(Technological Sciences)2010,53,12:10
5ACCURACY ANALYSIS OF 12-PARAMETER RECTANGULAR PLATE ELEMENTS WITH GEOMETRIC SYMMETRY显示文摘In this paper, it is proved that the double set parameter rectangular plate elements with geometric symmetry possess a very special convergence property, i.e., the consistency error due to nonconformity is of order O(h2) which is one order higher than that of ACM element and rectangular generalized conforming element proposed by Y. Q. Long, although all these elements have the same asympotical rate of convergence O(h) in the energy norm. This particular property seems to be never seen before for other nonconforming rectangular plate elements.SHI Dongyang CHEN Shaochun (Department of Mathematics, Zhengzhou University, Zhengzhou 450052, China) 2000Systems Science and Mathematical Sciences2000,13,2:6
6Flow frictional characteristics of microencapsulated phase change material suspensions flowing through rectangular minichannels显示文摘An experimental investigation was conducted on the laminar flow frictional characteristics of suspensions with microencapsulated phase change material (MEPCM) in water flowing through rectangular copper minichannels. The MEPCM was provided at an average particle size of 4.97 μm, and was mixed with distilled water to form suspen- sions with various mass concentrations ranging from 0 to 20%. The experiment was per- formed to explore the effect of MEPCM mass concentration on friction factor and pressure drop in the minichannels. The Reynolds number ranged from 200 to 2000 to provide laminar and transitional flows. It was found that the experimental data for the suspensions with 0 and 5% concentration agree well with the existing theoretical data for an incom- pressible, fully developed, laminar Newtonian flow. For the suspensions with mass con- centrations higher than 10%, there is an obvious increase in friction factor and pressure drop in comparison with laminar Newtonian flow.Frank Dammel Peter Stephan 2006Science China(Technological Sciences)2006,49,4:6
7Meshless Method for Analysis of Permeable Breakwaters in the Proximity of A Vertical Wall显示文摘In the present work, the improved version of the meshless singular boundary method(ISBM) is developed for analyzing the performance of bottom standing submerged permeable breakwaters in regular normally incident waves and in the proximity of a vertical wall. Both single and dual prismatic breakwaters of rectangular and trapezoidal forms are examined. The physical problem is cast in terms of the Laplace equation governing an irrotational flow and incompressible fluid motion with appropriate mixed type boundary conditions, and solved numerically using the ISBM. To model the permeability of the breakwaters fully absorbing boundary conditions are assumed. Numerical results are presented in terms of hydrodynamic quantities of the reflection coefficients. These are firstly validated against the results of a multi-domain boundary element method(BEM) developed independently for a previous study. The agreement between the results of the two methods is excellent. The coefficients of reflection are then computed and discussed for a variety of structural conditions including the breakwaters height, width, spacing, and absorbing permeability. Effects of the proximity of the vertical plane wall are also investigated. The breakwater's width is found to have only marginal effects compared with its height. Permeability tends to decrease the minimum reflections. These coefficients show periodic variations with the spacing relative to the wavelength. Trapezoidal breakwaters are found to be more cost-effective than the rectangular breakwaters. Dual breakwater systems are confirmed to perform much better than single structures.Nadji CHIOUKH Karim OUAZZANE Yal??n YüKSEL Benameur HAMOUDI Esin ?EVIK 2019China Ocean Engineering2019,33,2:6
8Process mineralogy as a key factor affecting the flotation kinetics of copper sulfide minerals显示文摘The aim of this study is to apply process mineralogy as a practical tool for further understanding and predicting the flotation kinetics of the copper sulfide minerals. The minerals' composition and association, grain distribution, and liberation within the ore samples were analyzed in the feed, concentrate, and the tailings of the flotation processes with two pulp densities of 25 wt% and 30 wt%. The major copper-bearing minerals identified by microscopic analysis of the concentrate samples included chalcopyrite(56.2 wt%), chalcocite(29.1 wt%),covellite(6.4 wt%), and bornite(4.7 wt%). Pyrite was the main sulfide gangue mineral(3.6 wt%) in the concentrates. A 95% degree of liberation with d_(80) > 80 μm was obtained for chalcopyrite as the main copper mineral in the ore sample. The recovery rate and the grade in the concentrates were enhanced with increasing chalcopyrite particle size. Chalcopyrite particles with a d_(80) of approximately 100 μm were recovered at the early stages of the flotation process. The kinetic studies showed that the kinetic second-order rectangular distribution model perfectly fit the flotation test data. Characterization of the kinetic parameters indicated that the optimum granulation distribution range for achieving a maximum flotation rate for chalcopyrite particles was between the sizes 50 and 55 μm.Ataallah Bahrami Mirsaleh Mirmohammadi Yousef Ghorbani Fatemeh Kazemi Morteza Abdollahi Abolfazl Danesh 2019International Journal of Minerals,Metallurgy and Materials2019,26,4:4
9THE METHOD OF THE RECIPROCAL THEOREM OF FORCED VIBRATION FOR THE ELASTIC THIN RECTANGULAR PLATES(Ⅰ)—RECTANGULAR PLATES WITH FOUR CLAMPED EDGES AND WITH THREE CLAMPED EDGES显示文摘In this paper the method of the reciprocal theorem(MRT)is extended to solve thesteady state responses of rectangular plates under harmonic disturbing forces.A series ofthe closed solutions of rectangular plates with various boundary conditions are given andthe tables and figures which have practical value are provided.MRT is a simple,convement and general method for solving the steady state responsesof rectangular plates under vartous harmonic disturbing forces.The paper contains three parts:(Ⅰ)rectangular plates with four clamped edges andwith three clamped edges:(Ⅱ)rectangular.plates with two adjacent clamped edges:(Ⅲ)cantilever plates.We are going to publish them one after another.付宝连 李农 1989Applied Mathematics and Mechanics(English Edition)1989,10,8:4
10Seismic cyclic loading test of SRC columns confined with 5-spirals显示文摘Presented herein is an experimental study on seismic resistance of rectangular steel reinforced concrete (SRC) columns confined with a new type of multi-spiral cage. The multi-spiral cage is a device of five interconnected spirals, named '5-spirals', with a large spiral at the center and four small ones at the corners. The innovation of applying the 5-spirals to SRC column is to take its superiority in concrete confinement and efficiency in automatic production for the precast construction industry. Four full-scale SRC columns were tested under horizontal cyclic loading. All of the tested columns were capable of sustaining a drift angle up to 6% radians. The hysteresis loops observed from the cyclic loading tests indicated that the spirally confined SRC columns demonstrated excellent performances in both strength and ductility. The test results suggested that with significant saving of the confinement steel, the newly innovated 5-spirals can be successfully applied to the precast rectangular SRC columns.WENG ChengChiang YIN YenLiang WANG JuiChen LIANG ChingYu 2008Science China(Technological Sciences)2008,51,5:4
11Closed-form solutions for free vibration of rectangular FGM thin plates resting on elastic foundation显示文摘This article presents closed-form solutions for the frequency analysis of rectangular functionally graded material(FGM) thin plates subjected to initially in-plane loads and with an elastic foundation. Based on classical thin plate theory, the governing differential equations are derived using Hamilton's principle. A neutral surface is used to eliminate stretching–bending coupling in FGM plates on the basis of the assumption of constant Poisson's ratio. The resulting governing equation of FGM thin plates has the same form as homogeneous thin plates. The separation-ofvariables method is adopted to obtain solutions for the free vibration problems of rectangular FGM thin plates with separable boundary conditions, including, for example, clamped plates. The obtained normal modes and frequencies are in elegant closed forms, and present formulations and solutions are validated by comparing present results with those in the literature and finite element method results obtained by the authors. A parameter study reveals the effects of the power law index n and aspect ratio a/b on frequencies.T. F. Xu Y. F. Xing 2016Acta Mechanica Sinica2016,32,6:4
12Higher-dimensional chaotic dynamics of a composite laminated piezoelectric rectangular plate显示文摘The analysis on the chaotic dynamics of a six-dimensional nonlinear system which represents the averaged equation of a composite laminated piezoelectric rectangular plate is given for the first time. The theory of normal form and the energy-phase method are combined to investigate the higher-dimen-sional chaotic dynamics of the composite laminated piezoelectric rectangular plate. Firstly,the theory of normal form is used to reduce the six-dimensional averaged equation to the simpler normal form. Then,the energy-phase method is extended to analyze the global bifurcations and chaotic dynamics of a six-dimensional nonlinear system. The analysis results indicate that there exist the homoclinic bi-furcation and Shilnikov type multi-pulse chaos for the composite laminated piezoelectric rectangular plate. Finally,numerical simulations are also used to investigate the nonlinear dynamic characteristics of the composite laminated piezoelectric rectangular plate. The results of numerical simulations also demonstrate that there exist the chaotic motions and the multi-pulse jumping orbits of the composite laminated piezoelectric rectangular plate.ZHANG Wei GAO MeiJuan YAO MingHui YAO ZhiGang 2009Science China(Physics,Mechanics & Astronomy)2009,52,12:4
13Sound quality evaluation of high-speed train interior noise by adaptive Moore loudness algorithm显示文摘An online experiment to acquire the interior noise of a China Railways High-speed (CRH) train showed that it wasmainly composed of middle-low frequency components and could not be described properly by linear or A-weighted soundpressure level (SPL). Thus, the appropriate way to evaluate the high-speed train interior noise is to use sound quality parameters,and the most important is loudness. To overcome the disadvantages of the existing loudness algorithms, a novel signal-adaptiveMoore loudness algorithm (AMLA) based on the equivalent rectangular bandwidth (ERB) spectrum was introduced. The valida-tion reveals that AMLA can obtain higher accuracy and efficiency, and the simulated dark red noise conforms best to thehigh-speed train interior noise by loudness and auditory assessment. The main loudness component of the interior noise is below27.6 ERB rate (erbr), and the sound quality of the interior noise is relatively stable between 300-350 km/h. The specific loudnesscomponents among 12-15 erbr stay invariable throughout the acceleration or deceleration process while components among20-27 erbr are evidently speed related. The unusual random noise is effectively identified, which indicates that AMLA is anappropriate method for sound quality assessment of the high-speed train under both steady and transient conditions.Le LUO, Xu ZHENG Zhi-yong HAO Wen-qiang DAI Wen-ying YANG 2017Journal of Zhejiang University-Science A(Applied Physics & Engineering)2017,18,9:3
14The refined theory of transversely isotropic piezoelectric rectangular beams显示文摘The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.GAO Yang1 & WANG Minzhong2 1. College of Science, China Agricultural University, Beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering Science, Peking University, Beijing 100871, China 2006Science China(Physics,Mechanics & Astronomy)2006,49,4:3
15E-IDEAL QUASI-REGULAR SEMIGROUPS显示文摘This paper defines a kind of quasi-regular semigroups and the so-called E-ideal quasiregular semigroups and gives some of its characteristics and its two special cases (E-left regular quasi-regular semigroups, E-semilattice quasi-regular semigroups), thus estabishing a structure theorem for it, and as corollaries, obtaining a construction for a left regular band and the known construction for bands (Petrich, 1967).任学明 郭聿琦 1989Science China Mathematics1989,32,12:3
16Finite-difference calculation of traveltimes based on rectangular grid显示文摘To the most of velocity fields, the traveltimes of the first break that seismic waves propagate along rays can be computed on a 2-D or 3-D numerical grid by finite-difference extrapolation. Under ensuring accuracy, to improve calculating efficiency and adaptability, the calculation method of first-arrival traveltime of finite-difference is derived based on any rectangular grid and a local plane wavefront approximation. In addition, head waves and scattering waves are properly treated and shadow and caustic zones cannot be encountered, which appear in traditional ray-tracing. The testes of two simple models and the complex Marmousi model show that the method has higher accuracy and adaptability to complex structure with strong vertical and lateral velocity variation, and Kirchhoff prestack depth migration based on this method can basically achieve the position imaging effects of wave equation prestack depth migration in major structures and targets. Because of not taking account of the later arrivals energy, the effect of its amplitude preservation is worse than that by wave equation method, but its computing efficiency is higher than that by total Green's function method and wave equation method.LI Zhen-chun(李振春) LIU Yu-lian(刘玉莲) ZHANG Jian-lei(张建磊) MA Zai-tian(马在田) WANG Hua-zhong(王华忠) 2004Acta Seismologica Sinica(English Edition)2004,17,6:2
17THE PROBLEMS OF NONLINEAR BENDING FOR ORTHOTROPIC RECTANGULAR PLATE WITH FOUR CLAMPED EDGES显示文摘(黄家寅)(秦圣立)THEPROBLEMSOFNONLINEARBENDINGFORORTHOTROPICRECTANGULARPLATEWITHFOURCLAMPEDEDGES¥HuangJiayin;QinShengli(QufuNormalUn...黄家寅 秦圣立 1996Applied Mathematics and Mechanics(English Edition)1996,17,3:2
18ON THE BENDING, VIBRATION AND STABILITY OF LAMINATED RECTANGULAR PLATES WITH TRANSVERSELY ISOTROPIC LAYERS显示文摘A method based on newly presented state space formulations is developed for analyzing the bending, vibration and stability of laminated transversely isotropic rectangular plates with simply supported edges. By introducing two displacement functions and two stress functions, two independent state equations were constructed based on the three-dimensional elasticity equations for transverse isotropy. The original differential equations are thus decoupled with the order reduced that will facilitate obtaining solutions of various problems.For the simply supported rectangular plate, two relations between the state variables at the top and bottom surfaces were established. In particular, for the free vibration (stability)problem, it is found that there exist two independent classes: One corresponds to the pure in-plane vibration (stability) and the other to the general bending vibration ( stability).Numerical examples are finally presented and the effects of some parameters are discussed.丁皓江 陈伟球 徐荣桥 2001Applied Mathematics and Mechanics(English Edition)2001,22,1:2
19Numerical solution of oscillatory flow of Maxwell fluid in a rectangular straight duct显示文摘A numerical analysis is presented for the oscillatory flow of Maxwell fluid in a rectangular straight duct subjected to a simple harmonic periodic pressure gradient.The numerical solutions are obtained by a finite difference scheme method.The stability of this finite difference scheme method is discussed.The distributions of the velocity and phase difference are given numerically and graphically.The effects of the Reynolds number,relaxation time,and aspect ratio of the cross section on the oscillatory flow are investigated.The results show that when the relaxation time of the Maxwell model and the Reynolds number increase,the resonance phenomena for the distributions of the velocity and phase difference enhance.Xuyang SUN Shaowei WANG Moli ZHAO Qiangyong ZHANG 2019Applied Mathematics and Mechanics(English Edition)2019,40,11:2
20NONLINEAR BENDING OF SIMPLY SUPPORTED RECTANGULAR SANDWICH PLATES显示文摘In this paper,fundamental equations and boundary conditions of the nonlinearbending theory for a rectangular sandwicl plate with a soft core are derived by meansof the method of calculus of variations.Then the nonlinear bending for a simplysupported rectangular sandwich plate under the uniform lateral load is investigated byuse of the perturbation method and a quite accurate analytic solution is obtained.刘人怀 成振强 1993Applied Mathematics and Mechanics(English Edition)1993,14,3:2
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