Chao Mei^1,2, Qifu Wang^1,*, Chen Yu¹, Zhaohui Xia¹

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 627-659, 2021, DOI:10.32604/cmes.2021.017704

Abstract This paper presents an effective fiber angle optimization method for two and multi-layered variable stiffness composites. A gradient-based fiber angle optimization method is developed based on isogeometric analysis (IGA). Firstly, the element densities and fiber angles for two and multi-layered composites are synchronously optimized using an extended Bi-layered continuous fiber angle optimization method (XBi-CFAO). The densities and fiber angles in the base layer are attached to the control points. The structure response and sensitivity analysis are accomplished using the non-uniform rational B-spline (NURBS) based IGA. By the benefit of the B-spline space, this method is free from checkerboards, and no… More >

Jiazheng Du^*, Ying Zhang, Fanwei Meng

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 661-687, 2021, DOI:10.32604/cmes.2021.017580

Abstract Traditional topology optimization methods may lead to a great reduction in the redundancy of the optimized structure due to unexpected material removal at the critical components. The local failure in critical components can instantly cause the overall failure in the structure. More and more scholars have taken the fail-safe design into consideration when conducting topology optimization. A lot of good designs have been obtained in their research, though limited regarding minimizing structural compliance (maximizing stiffness) with given amount of material. In terms of practical engineering applications considering fail-safe design, it is more meaningful to seek for the lightweight structure with… More >

Changshuo Wang¹, Liangqing Wang^2,*, Shigui Du¹, Jun Ye^1,3, Rui Yong¹

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 973-991, 2021, DOI:10.32604/cmes.2021.017453

Abstract To better estimate the rock joint shear strength, accurately determining the rock joint roughness coefficient (JRC) is the first step faced by researchers and engineers. However, there are incomplete, imprecise, and indeterminate problems during the process of calculating the JRC. This paper proposed to investigate the indeterminate information of rock joint roughness through a neutrosophic number approach and, based on this information, reported a method to capture the incomplete, uncertain, and imprecise information of the JRC in uncertain environments. The uncertainties in the JRC determination were investigated by the regression correlations based on commonly used statistical parameters, which demonstrated the… More >

Linfang Yu, Zhen Qin^*, Yi Ding, Zhiguang Qin

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 805-828, 2021, DOI:10.32604/cmes.2021.017332

Abstract As an important part of the new generation of information technology, the Internet of Things (IoT) has been widely concerned and regarded as an enabling technology of the next generation of health care system. The fundus photography equipment is connected to the cloud platform through the IoT, so as to realize the real-time uploading of fundus images and the rapid issuance of diagnostic suggestions by artificial intelligence. At the same time, important security and privacy issues have emerged. The data uploaded to the cloud platform involves more personal attributes, health status and medical application data of patients. Once leaked, abused… More >

Wei Wang^1,2, Yanfeng Zheng^1,3, Jingzhe Tang¹, Chao Yang¹, Yaozhi Luo^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 595-626, 2021, DOI:10.32604/cmes.2021.017321

Abstract Large deformation contact problems generally involve highly nonlinear behaviors, which are very time-consuming and may lead to convergence issues. The finite particle method (FPM) effectively separates pure deformation from total motion in large deformation problems. In addition, the decoupled procedures of the FPM make it suitable for parallel computing, which may provide an approach to solve time-consuming issues. In this study, a graphics processing unit (GPU)-based parallel algorithm is proposed for two-dimensional large deformation contact problems. The fundamentals of the FPM for planar solids are first briefly introduced, including the equations of motion of particles and the internal forces of… More >

Liang Mu, Hong Zhao^*, Yan Li, Xiaotong Liu, Junzheng Qiu, Chuanlong Sun

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 465-483, 2021, DOI:10.32604/cmes.2021.017276

Abstract Traffic flow statistics have become a particularly important part of intelligent transportation. To solve the problems of low real-time robustness and accuracy in traffic flow statistics. In the DeepSort tracking algorithm, the Kalman filter (KF), which is only suitable for linear problems, is replaced by the extended Kalman filter (EKF), which can effectively solve nonlinear problems and integrate the Histogram of Oriented Gradient (HOG) of the target. The multi-target tracking framework was constructed with YOLO V5 target detection algorithm. An efficient and long-running Traffic Flow Statistical framework (TFSF) is established based on the tracking framework. Virtual lines are set up… More >

Jingjing Zhao^1,*, Guangda Lu², Qing Zhang³, Wenchao Du⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 519-539, 2021, DOI:10.32604/cmes.2021.017268

Abstract As a typical brittle material, glass is widely used in construction, transportation, shipbuilding, aviation, aerospace and other industries. The unsafe factors of glass mainly come from its rupture. Thus, establishing a set of prediction models for the cracks growth of glass under dynamic load is necessary. This paper presents a contact damage model for glass based on the ordinary state-based peridynamic theory by introducing a contact force function. The Hertz contact (nonembedded contact) problem is simulated, and the elastic contact force is determined by adjusting the penalty factor. The proposed model verifies the feasibility of penalty-based method to simulate the… More >

Juan Ramón Bermejo Higuera¹, Javier Bermejo Higuera¹, Juan Antonio Sicilia Montalvo¹, Tomás Sureda Riera², Christopher I. Argyros³, Á. Alberto Magreñán^4,*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 541-565, 2021, DOI:10.32604/cmes.2021.017213

Abstract Security weaknesses in web applications deployed in cloud architectures can seriously affect its data confidentiality and integrity. The construction of the procedure utilized in the static analysis tools of source code security differs and therefore each tool finds a different number of each weakness type for which it is designed. To utilize the possible synergies different static analysis tools may process, this work uses a new method to combine several source codes aiming to investigate how to increase the performance of security weakness detection while reducing the number of false positives. Specifically, five static analysis tools will be combined with… More >

Junyu Chen¹, Yunwen Feng^1,*, Cheng Lu^1,2, Chengwei Fei²

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 1013-1027, 2021, DOI:10.32604/cmes.2021.016980

Abstract As the key component in aeroengine rotor systems, the health status of rolling bearings directly influences the reliability and safety of aeroengine rotor systems. In order to monitor rolling bearing conditions, a fusion fault diagnosis method, namely empirical mode decomposition (EMD)-Mahalanobis distance (E2MD) and improved wavelet threshold (IWT) (E2MD-IWT) for vibrational signals and acoustic emission (AE) signals is developed to improve the diagnostic accuracy of rolling bearings. The IWT method is proposed with a hard wavelet threshold and a soft wavelet threshold. Moreover, it is shown to be effective through numerical simulation. EMD is utilized to process the original AE… More >

Da Teng¹, Yunwen Feng^1,*, Cheng Lu^1,2, Chengwei Fei², Jiaqi Liu¹, Xiaofeng Xue^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 1029-1049, 2021, DOI:10.32604/cmes.2021.016945

Abstract Turbine blisks are assembled using blades, disks and casings. They can endure complex loads at a high temperature, high pressure and high speed. The safe operation of assembled structures depends on the reliability of each component. Monte Carlo (MC) simulation is commonly used to analyze structural reliability, but this method needs to run thousands of computations. In order to assess the clearance reliability of assembled structures in an efficient and precise manner, the novel Kriging-based decomposed-coordinated (DC) (DCNK) approach is proposed by integrating the DC strategy, the Kriging model and the importance sampling-based Markov chain (MCIS) technique. In this method,… More >