Jurica Sorić^*, Boris Jalušić, Tomislav Lesičar, Filip Putar, Zdenko Tonković

The International Conference on Computational & Experimental Engineering and Sciences, Vol.23, No.1, pp. 1-1, 2021, DOI:10.32604/icces.2021.08043

Abstract In modeling of material deformation responses, the physical phenomena such as stress singularity problems, strain localization and modeling of size effects cannot be properly captured by means of classical continuum mechanics. Therefore, various regularization techniques have been developed to overcome these problems. In the case of gradient approach the implicit gradient formulations are usually used when dealing with softening. Although the structural responses are mesh objective, they suffer from spurious damage growth. Therefore, a new formulation based on the strain gradient continuum theory, which includes both strain gradients and their stress conjugates, has been proposed.… More >

Roderick W. J. van Grootel, Allard T. van den Hoven, Dan Bowen, Tijmen Ris, Jolien W. Roos-Hesselink, Annemien E. van den Bosch^*

Congenital Heart Disease, Vol.16, No.3, pp. 221-232, 2021, DOI:10.32604/CHD.2021.013793 - 02 March 2021

Abstract Aims: To assess the prognostic value of left ventricular (LV) global longitudinal strain (GLS) and global longitudinal early diastolic strain rate (GLSre) with regard to cardiovascular events, as congenital aortic stenosis (AoS) is associated with significant mortality and morbidity but predictors for clinical outcome are scarce. Strain analysis provides a robust and reproducible method for early detection of LV dysfunction, which might be of prognostic value. Methods: This prospective study, included clinically stable patients with congenital AoS between 2011–2013. LV GLS and GLSre was performed in the apical 4, 3 and 2-chamber views using Tomtec software.… More >

Xiaorui Zhang^1,2,*, Hailun Wu¹, Wei Sun¹, Aiguo Song³, Sunil Kumar Jha⁴

Intelligent Automation & Soft Computing, Vol.27, No.3, pp. 873-889, 2021, DOI:10.32604/iasc.2021.013541 - 01 March 2021

Abstract Virtual surgery simulation is indispensable for virtual vascular interventional training system, which provides the doctor with visual scene between catheter and vascular. Soft tissue deformation, as the most significant part, determines the success or failure of the virtual surgery simulation. However, most soft tissue deformation model cannot simultaneously meet the requirement of high deformation accuracy and real-time interaction. To solve the challenge mentioned above, this paper proposes a fast and accurate vascular tissue simulation model based on point primitive method. Firstly, the proposed model simulates a deformation of the internal structure of the vascular tissue… More >

Mengcheng Sun^1,2, Weiya Xu^1,2,*, Huanling Wang^1,3, Qingxiang Meng^1,2, Long Yan^1,2, Wei-Chau Xie⁴

CMC-Computers, Materials & Continua, Vol.66, No.1, pp. 1057-1074, 2021, DOI:10.32604/cmc.2020.012537 - 30 October 2020

Abstract The narrowing deformation of reservoir valley during the initial operation period threatens the long-term safety of the dam, and an accurate prediction of valley deformation (VD) remains a challenging part of risk mitigation. In order to enhance the accuracy of VD prediction, a novel hybrid model combining Ensemble empirical mode decomposition based interval threshold denoising (EEMD-ITD), Differential evolutions—Shuffled frog leaping algorithm (DE-SFLA) and Least squares support vector machine (LSSVM) is proposed. The non-stationary VD series is firstly decomposed into several stationary subseries by EEMD; then, ITD is applied for redundant information denoising on special sub-series,… More >

Junfu Zhu¹, Qian Yin^1,2,*, Hongwen Jing¹, Xinshuai Shi¹, Minliang Chen^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.2, pp. 725-753, 2020, DOI:10.32604/cmes.2020.012648 - 12 October 2020

Abstract This study experimentally and numerically investigated the anchorage properties, bolt force evolution, deformation and stress fields of blocky rock mass with various dip angles of joint surfaces under an applied axial load. The results show that due to bolt reinforcement, the axial stress-strain curves of anchorage blocky rock mass show typical strain-hardening characteristics, and compared with models without anchorage, the peak strength and elastic modulus increase by 21.56% and 20.0%, respectively. With an increase in axial stress, the lateral strain continuously increases, and restriction effects of bolts reduce the overall deformation of model surfaces. The… More >

Xiaorui Zhang^1,2,*, Xuefeng Yu¹, Wei Sun², Aiguo Song³

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.3, pp. 1131-1147, 2020, DOI:10.32604/cmes.2020.09735 - 21 August 2020

Abstract In order to solve the problem of high computing cost and low simulation accuracy caused by discontinuity of incision in traditional meshless model, this paper proposes a soft tissue deformation model based on the Marquardt algorithm and enrichment function. The model is based on the element-free Galerkin method, in which Kelvin viscoelastic model and adjustment function are integrated. Marquardt algorithm is applied to fit the relation between force and displacement caused by surface deformation, and the enrichment function is applied to deal with the discontinuity in the meshless method. To verify the validity of the More >

Yalei Wang¹, Jinming Xu^1,2,*, Mostafa Asadizadeh³, Chuanjiang Zhong⁴, Xuejie Tao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 643-664, 2020, DOI:10.32604/cmes.2020.09866 - 20 July 2020

Abstract Granite is generally composed of quartz, biotite, feldspar, and cracks. The changes in digital parameters of these compositions reflect the detail of the deformation process of the rock. Therefore, the estimation of the changes in digital parameters of the compositions is much helpful to understand the deformation and failure stages of the rock. In the current study, after dividing the frames in the video images photographed during the axial compression test into four parts (or, the upper left, upper right, lower left, and lower right ones), the digital parameters of various compositions in each part… More >

Xinshuai Shi¹, Hongwen Jing^{1, *}, Jianguo Ning², Zhenlong Zhao¹, Junfu Zhu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 315-343, 2020, DOI:10.32604/cmes.2020.07955 - 19 June 2020

Abstract The stability control of gob-side entry retaining in fully mechanized caving face is a typical challenge in many coal mines in China. The rotation and subsidence of the lateral cantilever play a critical role in a coal mine, possibly leading to instability in a coal seam wall or a gob-side wall due to its excessive rotation subsidence. Hence, the presplitting blasting measures in the roof was implemented to cut down the lower main roof and convert it to caved immediate roof strata, which can significantly reduce the rotation space for the lateral cantilever and effectively… More >

Linze Wang¹, Dedong Gao^{1, *}, Jiajie Fu¹, Yuzhou Luo², Shijian Zhao¹

CMC-Computers, Materials & Continua, Vol.64, No.2, pp. 1153-1169, 2020, DOI:10.32604/cmc.2020.010073 - 10 June 2020

Abstract In order to get to the desired target inside the body, it is essential to investigate the needle-tissue coupling process and calculate the tissue deformation. A cantilever beam model is presented to predicting the deflection and bending angle of flexible needle by analyzing the distribution of the force on needle shaft during the procedure of needle insertion into soft tissue. Furthermore, a finite element (FE) coupling model is proposed to simulate the needle-tissue interactive process. The plane and spatial models are created to relate the needle and tissue nodes. Combined with the cantilever beam model… More >

Yongping Yu¹, Lihui Chen¹, Shaopeng Zheng¹, Baihui Zeng¹, Weipeng Sun^{2, ∗}

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.1, pp. 185-200, 2020, DOI:10.32604/cmes.2020.07997 - 01 April 2020

Abstract This paper is focused on the post-buckling behavior of the fixed laminated composite beams with effects of axial compression force and the shear deformation. The analytical solutions are established for the original control equations (that is not simplified) by applying the Maclaurin series expansion, Chebyshev polynomials, the harmonic balance method and the Newton’s method. The validity of the present method is verified via comparing the analytical approximate solutions with the numerical ones which are obtained by the shooting method. The present third analytical approximate solutions can give excellent agreement with the numerical solutions for a More >