L. Nobile¹, C. Carloni¹

Structural Durability & Health Monitoring, Vol.2, No.2, pp. 83-90, 2006, DOI:10.3970/sdhm.2006.002.083

Abstract The analysis of buckling of elastic columns is one of the first problem in structural engineering that was historically solved. Critical loads of perfect columns with various end restrains have been derived. Nevertheless, the perfect column is an idealized model. In reality, unavoidable imperfections should be considered. Solutions for transversal disturbing load, crookedness or load eccentricity have been proposed. Another frequent imperfection to be taken into account is the weakness at an interior location due to a partial edge crack. In this paper the influence of this type of imperfection on the critical load is analyzed. The case of the… More >

NANCY RODRÍGUEZ, NORA MAYER, HÉCTOR F. GAUNA

BIOCELL, Vol.31, No.1, pp. 67-74, 2007, DOI:10.32604/biocell.2007.31.067

Abstract Prenatal stimulations have been shown to have long-term effects on at reproductive activity. We evaluated the influence of the prenatal stress on the hypothalamic-pituitary-gonad (HPG) axis in male offsprings from mothers with high number of offsprings per litter (HNL) and low number of offsprings per litter (LNL) after hypothesizing that the number of offsprings per litter may modify the effect of the prenatal stress on the HPG of adult offsprings. Pregnant Wistar rats were used for this study. Immobilization (IMO) stress was used, 30 min, 3 times per week, from the 5th to 21st day of pregnancy. The weight of… More >

Yewan Ma, Hansen Chang, Zhaowang Wu, Yanyan Jiang, Juan Li, Xunchang Yin, Quanjin Liu, Lihua Zhang^*

Sound & Vibration, Vol.53, No.4, pp. 139-149, 2019, DOI:10.32604/sv.2019.04622

Abstract The energy of a spring with a well-distributed mass m_s is theoretically studied in this paper. The solution of the wave equation is derived in detail, and then the kinetic energy and potential energy of the spring are studied with the wave equation, as well as the kinetic energy of the oscillating mass M. The kinetic energy and potential energy of the spring, and total energy are numerically simulated for different ratios m_s/M with considering the spring’s mass, which makes the property of energy of the oscillating system understood easily. More >

Ahmet Daşdemir^*

Sound & Vibration, Vol.53, No.3, pp. 65-74, 2019, DOI:10.32604/sv.2019.04087

Abstract In this paper, we present our report on the forced vibration of a bi-layered plate-strip with initial stress resting on a rigid foundation induced by a time-harmonic force. The investigation is carried out according to the piecewise homogeneous body model with utilizing the three-dimensional linearized theory of elastic waves in initially stressed bodies (TLTEWISB). The materials of the body are chosen to be linearly elastic, homogeneous, and isotropic. The interface between the layers is assumed to be imperfect, and is simulated by the spring-layer model. A similar degree of imperfection on the interface is realized in the normal and tangential… More >

Dein Shaw, Chih Ren Huang, Yi Chi Pan

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.1, pp. 7-8, 2011, DOI:10.3970/icces.2011.018.007

Abstract A nonlinear curved spring has a free form shape. In this study, the curved beam is applied a nonlinear load, the load on the spring is pointed to a certain point of the space. This curved spring can be used in an orthosis. A certain load-deformation relation of curved spring which used in orthosis can assist the subject wearing the orthosis to climb the stairs. The analysis of the curved spring should be non-linear due to the applied load is a constant but its direction is point to a certain point. The deformation is hard predicted correctly for this spring.… More >

Zhengfa Li, Weibin Song, Zhengdao Wang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.1, pp. 11-12, 2011, DOI:10.3970/icces.2011.017.011

Abstract By using the high froze/recovery strains of shape memory polymers to meet the requirements of deployable space structures, the folding behavior of shape memory tape spring structures consisting of shape memory polymer and metal spring was analyzed. Firstly, numerical simulations were performed on the buckling modes and affecting factors under the equal- and opposite-sense bends. The results show that the folding deformations of such structure in the two cases are completely different. The equal-sense bending leads to the structure buckled abruptly, but gradual torsion buckling is received in the case of opposite-sense bending. The critical bending moments have big difference… More >

Z. Damián-Noriega¹, R. Pérez-Moreno¹, S.A. Villanueva-Pruneda¹, V.M. Domínguez-Hernández², J.P.A. Puerta-Huerta¹, C. Huerta-Muñoz³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.8, No.1, pp. 25-30, 2008, DOI:10.3970/icces.2008.008.025

Abstract In this work, a new equation to predict the springback in the bending and rolling processes of metallic sheet is presented. This equation has been experimentally applied in the design of a wood truncated cone to form an aluminum sheet truncated cone. Kalpakjian's equation was also applied but Damian's equation has given the best performance. More >

Dein Shaw¹, Chih Ren Huang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.10, No.1, pp. 37-38, 2009, DOI:10.3970/icces.2009.010.037

Abstract The purpose of this research is to propose a design method for displacement path of a curved nonlinear spring (As shown in Fig. 1). The design method is divided the spring into several nonlinear linear spring segments of coordinates to be determined connecting points (nodal points). The relation between external load and displacement is defined by the request of user. The relation between load and displacement of each line segment of the spring is presented by large deformation theorem. The prior known variables are moment of inertia, cross section area, material property and load path. Those variables can be input… More >

S. D. Akbarov^1,2, C. Ipek³

CMC-Computers, Materials & Continua, Vol.30, No.2, pp. 99-144, 2012, DOI:10.3970/cmc.2012.030.099

Abstract This paper studies the dispersion of the axisymmetric longitudinal wave propagation in the pre-strained hollow cylinder consisting of two-layers under the shear-spring type imperfectness of the contact conditions between these layers. The investigations are made within the framework of the piecewise homogeneous body model by utilizing the 3D linearized theory of elastic waves in elastic bodies with initial stresses. It is assumed that the layers of the cylinder are made from compressible hyper-elastic materials and their elasticity relations are given through the harmonic potential. The degree of the mentioned imperfectness is estimated by the shear-spring parameter. Numerical results on the… More >

H.Q. Nguyen¹, C.-D. Tran¹, T. Tran-Cong¹

CMES-Computer Modeling in Engineering & Sciences, Vol.105, No.5, pp. 399-439, 2015, DOI:10.3970/cmes.2015.105.399

Abstract In this paper, dynamic behaviours of dilute polymer solutions of various bead-spring chain models in shear flow are studied using a coarse-grained method based on the Integrated Radial Basis Function Networks (IRBFNs) and stochastic technique. The velocity field governed by the macroscopic conservation equations is determined by the IRBFN-based method, whereas the evolution of configurations of polymer chains governed by the diffusion stochastic differential equations are captured by the Brownian Configuration Field (BCF) approach. The system of micro-macro equations is closed by the Kramers’ expression, which allows for the determination of the polymer stresses in terms of BCF configurations. In… More >