Abdoullah Namdar^1,2,3,*

Structural Durability & Health Monitoring, Vol.15, No.2, pp. 167-182, 2021, DOI:10.32604/sdhm.2021.011127

Abstract The nonlinearity of the strain energy at an interval period of applying seismic load on the geostructures makes it difficult for a seismic designer to makes appropriate engineering judgments timely. The nonlinear stress and strain analysis of an embankment is needed to evaluate by using a combination of suitable methods. In this study, a large-scale geostructure was seismically simulated and analyzed using the nonlinear finite element method (NFEM), and linear regression method which is a soft computing technique (SC) was applied for evaluating the results of NFEM, and it supports engineering judgment because the design of the geostructures is usually… More >

Fang Shi^1,*, Daobing Wang², Xiaogang Chen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.127, No.2, pp. 575-598, 2021, DOI:10.32604/cmes.2021.015384

Abstract Field data suggests that carbonate reservoirs contain abundant natural fractures and cavities. The propagation mechanisms of hydraulic fractures in fracture-cavity reservoirs are different from conventional reservoirs on account of the stress concentration surrounding cavities. In this paper, we develop a fully coupled numerical model using the extended finite element method (XFEM) to investigate the behaviors and propagation mechanisms of hydraulic fractures in fracture-cavity reservoirs. Simulation results show that a higher lateral stress coefficient can enhance the influence of the natural cavity, causing a more curved fracture path. However, lower confining stress or smaller in-situ stress difference can reduce this influence,… More >

Yezhi Qin, Ying Wang, Zhikai Wang^*, Xiongliang Yao

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 1093-1123, 2021, DOI:10.32604/cmes.2021.012969

Abstract The shock wave of the underwater explosion can cause severe damage to the ship structure. The propagation characteristics of shock waves near the structure surface are complex, involving lots of complex phenomena such as reflection, transmission, diffraction, and cavitation. However, different structure surface boundaries have a significant effect on the propagation characteristics of pressure. This paper focuses on investigating the behavior of shock wave propagation and cavitation from underwater explosions near various structure surfaces. A coupled Runge–Kutta discontinuous Galerkin (RKDG) and finite element method (FEM) is utilized to solve the problem of the complex waves of fluids and structure dynamic… More >

Mai Ramadan Ibraheem¹, Jilan Adel², Alaa Eldin Balbaa³, Shaker El-Sappagh⁴, Tamer Abuhmed^5,*, Mohammed Elmogy⁶

CMC-Computers, Materials & Continua, Vol.67, No.1, pp. 393-409, 2021, DOI:10.32604/cmc.2021.014446

Abstract Surface electromyogram (sEMG) processing and classification can assist neurophysiological standardization and evaluation and provide habitational detection. The timing of muscle activation is critical in determining various medical conditions when looking at sEMG signals. Understanding muscle activation timing allows identification of muscle locations and feature validation for precise modeling. This work aims to develop a predictive model to investigate and interpret Patellofemoral (PF) osteoarthritis based on features extracted from the sEMG signal using pattern classification. To this end, sEMG signals were acquired from five core muscles over about 200 reads from healthy adult patients while they were going upstairs. Onset, offset,… More >

TIANQI WANG, WANXI YANG^*

BIOCELL, Vol.44, No.4, pp. 469-478, 2020, DOI:10.32604/biocell.2020.014708

Abstract Mitochondria are important in eukaryotic cells due to their functions in energy production and regulation over other cellular activities. Oocytes are produced by a long and precisely controlled process, the dysfunction of which leads to impaired female fertility. As oocytes mature, mitochondria are constantly under the regulation of nuclear genes, the process of which can be modulated by extracellular signals. Understanding how nuclear genes regulate mitochondrial functions is important for studying animal reproduction and human fertility. As more and more genes regulating mitochondrial functions in oocytes are being revealed, new approaches for improving female fertility in both human and animals… More >

Chuanyong Qu^*, Hui Yuan

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.2, pp. 829-847, 2020, DOI:10.32604/cmes.2020.012407

Abstract Microdamage is produced in bone tissue under the long-term effects of physiological loading, as well as age, disease and other factors. Bone remodeling can repair microdamage, otherwise this damage will undermine bone quality and even lead to fractures. In this paper, the damage variable was introduced into the remodeling algorithm. The new remodeling algorithm contains a quadratic term that can simulate reduction in bone density after large numbers of loading cycles. The model was applied in conjunction with the 3D finite element method (FEM) to the remodeling of the proximal femur. The results showed that the initial accumulation of fatigue… More >

Miaomiao Ren^*, Xiaobin Shu

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 979-991, 2020, DOI:10.32604/fdmp.2020.09563

Abstract A novel algorithm is proposed for the simulation of fluid-structure interaction problems. In particular, much attention is paid to natural phenomena such as debris flow. The fluid part (debris flow fluid) is simulated in the framework of the smoothed particle hydrodynamics (SPH) approach, while the solid part (downstream obstacles) is treated using the finite element method (FEM). Fluid-structure coupling is implemented through dynamic boundary conditions. In particular, the software “TensorFlow” and an algorithm based on Python are combined to conduct the required calculations. The simulation results show that the dynamics of viscous and non-viscous debris flows can be extremely different… More >

Priyaranjan Pal^*

Sound & Vibration, Vol.54, No.3, pp. 179-200, 2020, DOI:10.32604/sv.2020.010679

Abstract This study determines the natural frequencies of the lock gate structure, considering the coupled effect of reservoir fluid on one side using the finite element method (FEM). The gate is assumed to be a uniformly thick plate, and its material is isotropic, homogeneous, and elastic. The reservoir fluid is assumed to be inviscid and incompressible in an irrotational flow field. The length of the reservoir domain is truncated using the far boundary condition by adopting the Fourier series expansion theory. Two different assumptions on the free surface, i.e., undisturbed and linearized, are considered in the fluid domain analysis. The computer… More >

Ruiyuan Xue¹, Shurong Yu^{1, *}, Xiheng Zhang¹

CMC-Computers, Materials & Continua, Vol.65, No.1, pp. 789-805, 2020, DOI:10.32604/cmc.2020.011340

Abstract Nuclear power plants (NPP) contain plenty of valve piping systems (VPS’s) which are categorized into high anti-seismic grades. Tasks such as seismic qualification, health monitoring and damage diagnosis of VPS’s in its design and operation processes all depend on finite element method. However, in engineering practice, there is always deviations between the theoretical and the measured responses due to the inaccurate value of the structural parameters in the model. The structure parameters identification of VPS within NPP is still an unexplored domain to a large extent. In this paper, the initial 2Dfinite element model (FEM) for VPS with a DN80… More >

Xiaozhong Chen^*

Molecular & Cellular Biomechanics, Vol.17, No.3, pp. 139-153, 2020, DOI:10.32604/mcb.2020.08933

Abstract Existing model registration of individual bones does not have a high certainly of success due to the lack of anatomic semantic. In light of the surface anatomy and functional structure of bones, we hypothesized individual femur models would be aligned through feature points both in geometrical level and in anatomic level, and proposed a hierarchical approach for the rigid registration (HRR) of point cloud models of femur with high resolution. Firstly, a coarse registration between two simplified point cloud models was implemented based on the extraction of geometric feature points (GFPs); and then, according to the anatomic feature points (AFPs)… More >