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Study on bending of Woven Fabrics Using Linear Viscoelasticity Theory

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Journal of China Textile University(English Edition) 2000年第1期17卷 51-56页

作者：石风俊胡金莲余同希

The bending behavior of woven fabrics under low curva-ture conditions has been analyzed by linear *** fabric is assumed to behave viscoelasticallyand to be subjected to frictional restraints in bending *** frictional restraint is considered to beproportional to the curvature and can be described by africtional moment.A model has been constructed by astandard three-element solid model and a paralleledfrictional sliding *** equations of the model fora cyclic curvature variation are derived.A set of param-eters of the equations for each fabric has been *** of the bending rigidity andhysteresis for wool,cashmere,wool/polyester blended,polyester and cotton fabrics are made,displaying verygood agreement with the experimental observations.

关键词： bending rigidity bending hysteresis linear vis-coelasticity woven fabric.

Limit Analysis for Reinforced Concrete Rectangular Members Under bending, Shear and Torsion

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Journal of Shanghai Jiaotong university(Science) 2014年第2期19卷 129-138页

作者：陈溪刘西拉 Department of Solid Mechanics Shanghai Jiaotong University Department of Civil Engineering Shanghai Jiaotong University

The ultimate strength of reinforced concrete(RC) rectangular members subjected to combined bending,shear and torsion is obtained from the limit analysis proposed in the present paper. Based on a warped failure surface determined by external loads, and a reasonable assumed stress distribution balancing external loads but not violating the yield condition, the bending-shear-torsion interaction can be derived from equilibrium *** to the definition of lower-bound theorem in limit analysis, the calculated ultimate loads will be carried safely by the structure. The present method is a simple approach to obtain carrying capacities for RC elements under complex external loads. After comparing with the test results, a good agreement has been observed. The present method can be extended to explain the failure mechanism of RC members subjected to axial loads, and it is possible to develop a simple unified theory of RC members for engineering.

关键词： reinforced concrete(RC) beam rectangular section limit analysis bending shear torsion

Study on the bending Properties of Woven Fabrics and Its Yarns

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Journal of Donghua University(English Edition) 2002年第4期19卷 7-11页

作者：王府梅吴雄英 College of Textiles Dong Hua UniversityShanghaiChina200051 Shanghai Entry-Exit Inspection and Quarantine Bureau of P.R.C. ShanghaiChina 200135

A theoretical analysis on the two extreme cases of yarn bending rigidity as well as the relationship between them is proposed. The significant influence of fiber-to-fiber interaction on yarn bending rigidity is *** observation on the relationship between fabric/yarn bending property and fiber fineness, yarn structure, fabric structure is given as we ll. Three problems are discussed and the following conclusion is thus obtained. There exists, similar t0 a rigid engineering rod, a linear relationship between yarn bending rigidity and the square of yarn fineness (expressed as yarn count in tex), but the increasing speed is much lower. Yarn bending rigidity in the fabric also to a great extent depends on the fabric density and yarn twist factor, and so on. Fabric's bending hysteresis primarily depends on its bending rigidity.

关键词： bending rigidity, bending hysteresis, fabric, yarn

Study on the application of active balancing device to solve the vibration problem for the rotor with bending fault

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High Technology Letters 2006年第3期12卷 225-230页

作者：何立东 Shen Wei Gao Jinji Zhou Weihua Beijing University of Chemical Tectmology Beijing 100029 P.R. China

The rotor with bending faults that occurrs on the rotating machinery usually vibrates seriously. This paper investigates to apply the active balancing device on a flexible rotor with bending faults to solve the vibration problem. Two problems are studied by finite element method firstly： Where the balance actuator is fixed on the shaft and how much the balancing capacity of the active balancing device is needed. The experiment is then carried out on the test rig, which consists of a flexible rotor with bending faults. The test results indicate that the bending rotor peak vibration response can be decreased from 550~m to 40~tm below by using the active balancing device. The peak vibration response decreases approximately by 93 %. The synchronous vibration due to the rotor bending faults can be controlled effectively by using ac- tive balancing device. The active balancing device is especially adapted to solve the problem caused by thermal distortion with time-variation and randomness, which is varied with working conditions, thus it has good practical value in practice.

关键词： active balancing bending turbomachinery vibration FEA

bending AND VIBRATION OF COMPOSITE LAMINATED PLATES

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Applied Mathematics and Mechanics(English Edition) 1989年第4期10卷 345-352页

作者：邓梁波 Northwestern Polytechnical University Xi'an

Hybrid-stress finite element method is applied for analysis of bending and vibration ofcomposite laminated plates in this ***,based on the modified-complementaryprinciple,a reciangular hybrid-stress plate bending element is presented which applies toanalysis of *** the element,different stress parameters are assumedaccording to different *** boundary displacements are determined by means of theassumption of YNS theory on the boundary of *** element formed in this way notonly can take effects of transverse shear deformation and local warping into account,butalso has less degrees of *** of bending and vibration of laminates aresolved by using this *** the numerical results are compared with the *** shows that the results obtained in the paper are very close to the exactresults.

关键词： laminated bending freedom assumed transverse interlayer interior compatible coordinate stiffness

Hydrotropism： Root bending Does Not Require Auxin Redistribution

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Molecular Plant 2016年第5期9卷 757-759页

作者： Doron Shkolnik Gat Krieger Roye Nuriel Hillel Fromm Department of Molecular Biology&Ecology of Plants Faculty of Life SciencesTel Aviv UniversityTel Aviv 69978Israel

Dear Editor The widely accepted Chotodny-Went theory posits that asym- metrical auxin redistribution is required for tropic growth of plant organs. We demonstrate, using the sensitive auxin-sensor protein DII-VENUS that, in the presence and absence of auxin polar transport inhibitors, root tropism toward moisture （hydrotro- pism） does not involve auxin redistribution. Moreover, highly specific auxin signaling antagonists accelerate hydrotropism. Thus, hydrotropism is an exception to the Cholodny-Went theory.

关键词： bending Require Redistribution

Simulation and experimental verification of off-axis fiber Bragg grating bending sensor with high refractive index modulation

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Optoelectronics Letters 2022年第4期18卷 200-203页

作者： CUI Wei ZHOU Yanfang YAN Zhonghua GUO Junqi YUE Yiting CHEN Hao Chongqing Engineering Research Center of Intelligent Sensing Technology and Microsystem Chongqing University of Post and TelecommunicationsChongqing 400065China

Off-axis FBG simulations were performed in this paper using a finite element method in conjunction with the conformal mapping technique to study the bending sensing characteristics of the off-axis FBG with high index *** refractive index(RI)increase of the grating region is taken into consideration for the mode field *** influences of high RI increase and the offset distance of the grating on the bending sensitivity were ***-axis FBGs with different offset distances were fabricated using femtosecond laser with phase mask technique in standard single-mode *** simulation results were verified by the experiment.A bending sensitivity of 0.055 d B/m^(-1) was achieved with an offset distance of 4μ*** simulation and experiment results suggest that the grating offset distance has a greater influence on the sensitivity of the off-axis FBG with high RI modulation than that with low RI *** proposed sensor structure and simulation results can provide suggestion for the design and processing of off-axis FBG bending sensors.

关键词： fiber bending offset

Nonlinear dynamic behavior of rubbing rotor under interaction between bending and torsional vibrations

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Journal of Harbin Institute of Technology(New Series) 2002年第2期9卷 117-120页

作者：刘占生崔颖韩万金隋玉秋黄文虎 Sch. of Energy Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

The nonlinear dynamic behavior of a rubbing rotor system was studied with a mathematical model established with the eccentricity and interaction between bending and torsional vibrations taken into consideration. The nonlinear vibrational response of a rubbing rotor was analyzed using numerical integral, spectroscopic analysis and Poince mapping method, which made it possible to have better understanding of the vibrational characteristics of partial rubbing and complete circular rubbing rotors. The numerical results reveal the response of torsional vibration mainly takes a form of superchronous motion, and its frequency decreases as the rotational speed increases when partial rubbing occurs, and the response of torsional vibration is synchronous when complete circular rubbing occurs. The comparison of the dynamics of rubbing rotors with and without the interaction between bending and torsional vibrations shows the interaction between bending and torsional vibrations advances the rotational speed, at which the response of bending vibration changes from a synchronous motion into a quasi periodic motion, and the interaction between bending and torsional vibrations reduces stability of the rubbing rotor.

关键词： interaction between bending and torsional vibrations rubbing rotor bifurcation

THE ELASTIC-PLASTIC bending AND WRINKLING OF THIN CIRCULAR PLATES

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Chinese Science Bulletin 1990年第19期35卷 1602-1607页

作者：章亮炽余同希 Department of Mechanics Zhejiang University Hangzhou 310027 PRC Department of Mechanics Peking University Beijing 100871 PRC

Ⅰ. INTRODUCTIONThin circular plates, a kind of the basic structural element widely used in engineering,are of the simplest plane-stress mechanical model with double curvatures. Hence, the investigation on the fundamental mechanical properties of the thin circular plates has been attracting great attention and brought about many results. Due to the difficulties

关键词： thin circular plate elastic-plastic bending wrinkling.