Yongfeng Zhang¹, Hanchen Huang^1,2, Satya N. Atluri³

CMES-Computer Modeling in Engineering & Sciences, Vol.35, No.3, pp. 215-226, 2008, DOI:10.3970/cmes.2008.035.215

Abstract Molecular dynamics simulations reveal the asymmetrical yield strength of twinned copper nanowires under tension and compression. The simulation results show that the strength of nanowires depends on loading conditions, morphologies, and twin spacing. Under tensile loading condition the Schmidt factor of the leading partial is larger than that under compression. Effectively, the yield strength under tension is smaller than that under compression. When the cross-section is circular in morphology, dislocation nucleation requires larger stress, and the asymmetry of yield strength depends on the nucleation stress. When the cross section is square in morphology, dislocation nucleation More >

Jorge Daniel Riera¹, Letícia Fleck Fadel Miguel², Ignacio Iturrioz³

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.2, pp. 113-136, 2011, DOI:10.32604/cmes.2011.082.113

Abstract In the truss-like Discrete Element Method (DEM), masses are considered lumped at nodal points and interconnected by means of uni-dimensional elements with arbitrary constitutive relations. In previous studies of the tensile fracture behavior of concrete cubic samples, it was verified that numerical predictions of fracture of non-homogeneous materials using DEM models are feasible and yield results that are consistent with the experimental evidence so far available. Applications that demand the use of large elements, in which extensive cracking within the elements of the model may be expected, require the consideration of the increase with size… More >

H. T. Wang¹, Z. H. Yao²

CMES-Computer Modeling in Engineering & Sciences, Vol.29, No.1, pp. 1-14, 2008, DOI:10.3970/cmes.2008.029.001

Abstract Carbon nanotubes (CNTs) may provide ultimate enhancement in stiffness and strength for composite materials. This paper presents a rigid-fiber-based boundary integral equation formulation for the numerical simulation of debonding process and the corresponding strength of CNT reinforced composites. The CNT/matrix interfaces are assumed to fail when the interfacial shear force reaches a prescribed threshold, and the CNTs and matrix are considered to be detached in the failed areas. The matrix with one or several tens of originally well-bonded CNTs is subjected to an incremental tensile load and the effective stress-strain relations are readily obtained by… More >

Ju Li¹, Sidney Yip¹

CMES-Computer Modeling in Engineering & Sciences, Vol.3, No.2, pp. 219-228, 2002, DOI:10.3970/cmes.2002.003.219

Abstract We examine the role of atomistic simulations in multiscale modeling of mechanical behavior of stressed solids. Theoretical strength is defined through modes of structural instability which, in the long wavelength limit, are specified by criteria involving elastic stiffness coefficients and the applied stress; more generally, strength can be characterized by the onset of soft vibrational modes in the deformed lattice. Alternatively, MD simulation of stress-strain response provides a direct measure of the effects of small-scale microstructure on strength, as illustrated by results on SiC in single crystal, amorphous, and nanocrystalline phases. A Hall-Petch type scaling More >

Toru Ikeda¹, Isao Arase, Yuya Ueno, Noriyuki Miyazaki

CMES-Computer Modeling in Engineering & Sciences, Vol.1, No.1, pp. 91-98, 2000, DOI:10.3970/cmes.2000.001.091

Abstract In electronic devices, the corners of joined dissimilar materials exist between plastic resin and a die pad or a chip. Failure of the plastic resin is often caused from these corners during the assembly process or the operation of products. The strength evaluation of the corner is important to protect the failure of plastic packages. To evaluate the singular stress field around a corner, we utilize the stress intensity factors of the asymptotic solution for a corner of joined dissimilar materials. We show that the accurate stress intensity factor can be analyzed by the displacement More >

S.A. Yıldızel^1,2, A.U. Öztürk¹

CMC-Computers, Materials & Continua, Vol.52, No.1, pp. 41-52, 2016, DOI:10.3970/cmc.2016.052.041

Abstract In this study, artificial neural networks trained with swarm based artificial bee colony optimization algorithm was implemented for prediction of the modulus of rapture values of the fabricated glass fiber reinforced concrete panels. For the application of the ANN models, 143 different four-point bending test results of glass fiber reinforced concrete mixes with the varied parameters of temperature, fiber content and slump values were introduced the artificial bee colony optimization and conventional back propagation algorithms. Training and the testing results of the corresponding models showed that artificial neural networks trained with the artificial bee colony More >

A. Ramach,ra Murthy^1,2, V. Ramesh Kumar¹, Smitha Gopinath¹, PrabhatRanjan Prem¹, Nagesh R. Iyer³, Reshmi Balakrishnan⁴

CMC-Computers, Materials & Continua, Vol.44, No.1, pp. 59-72, 2014, DOI:10.3970/cmc.2014.044.059

Abstract This paper investigates the flexural performance of a sandwich panel made up of ultra high strength concrete (UHSC) as top and bottom skin and cold formed steel as sandwich. A novel sandwich panel has been designed such a way that bottom skin of UHSC is of precast in nature and top skin of UHSC is cast-insitu and cold formed steel (profiled sheet) as sandwich. The connection between top skin of UHSC and cold formed steel is made with self tapping screws. Flexural performance of UHSC sandwich panel has been tested under flexural loading and it… More >

Asif Husain¹, M. Guniganti², D. K. Sehgal², R. K. Pandey²

CMC-Computers, Materials & Continua, Vol.8, No.3, pp. 133-150, 2008, DOI:10.3970/cmc.2008.008.133

Abstract This paper describes an approach to identify the mechanical properties i.e. fracture and yield strength of steels. The study involves the FE simulation of shear punch test for various miniature specimens thickness ranging from 0.20mm to 0.80mm for four different steels using ABAQUS code. The experimental method of the miniature shear punch test is used to determine the material response under quasi-static loading. The load vs. displacement curves obtained from the FE simulation miniature disk specimens are compared with the experimental data obtained and found in good agreement. The resulting data from the load vs.… More >

Lin Wang^1,*, Huixiang Liu¹, Wenyuan Liu^1,2, Nan Jing¹, Ahmad Adnan¹, Chenshu Wu³

CMC-Computers, Materials & Continua, Vol.58, No.2, pp. 437-449, 2019, DOI:10.32604/cmc.2019.03814

Abstract The indoor subarea localization has wide application space in dynamic hot zone identification, indoor layout optimization, store dynamic pricing and crowd flow trend prediction. The ubiquitous mobile devices provide the opportunity for wireless fingerprinting-based indoor localization services. However, there are two short board where the existing methods have been criticized. One is that a tagging approach requires a large number of professional surveys for wireless fingerprint construction, which weakens the scalability of the methods. The other is that the crowdsourcing-based methods encounter the cold boot problem in the system initial stage. To address these issues,… More >

Wenyan Liu¹, Xiangyang Luo^1,*, Yimin Liu¹, Jianqiang Liu², Minghao Liu¹, Yun Q. Shi³

CMC-Computers, Materials & Continua, Vol.55, No.1, pp. 71-93, 2018, DOI:10.3970/cmc.2018.055.071

Abstract Precise localization techniques for indoor Wi-Fi access points (APs) have important application in the security inspection. However, due to the interference of environment factors such as multipath propagation and NLOS (Non-Line-of-Sight), the existing methods for localization indoor Wi-Fi access points based on RSS ranging tend to have lower accuracy as the RSS (Received Signal Strength) is difficult to accurately measure. Therefore, the localization algorithm of indoor Wi-Fi access points based on the signal strength relative relationship and region division is proposed in this paper. The algorithm hierarchically divide the room where the target Wi-Fi AP… More >