Jili Chen^1,2, Hailan Wang², Xiaolan Xie^1,2,*

Computer Systems Science and Engineering, Vol.48, No.3, pp. 645-663, 2024, DOI:10.32604/csse.2023.037957 - 20 May 2024

Abstract Fuzzy C-Means (FCM) is an effective and widely used clustering algorithm, but there are still some problems. considering the number of clusters must be determined manually, the local optimal solutions is easily influenced by the random selection of initial cluster centers, and the performance of Euclid distance in complex high-dimensional data is poor. To solve the above problems, the improved FCM clustering algorithm based on density Canopy and Manifold learning (DM-FCM) is proposed. First, a density Canopy algorithm based on improved local density is proposed to automatically deter-mine the number of clusters and initial cluster… More >

Liang Yi^1,*, Wen Gang¹, Nenggui Pan², Wangui Wang¹, Shengshuai Mo¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2777-2790, 2023, DOI:10.32604/fdmp.2023.021907 - 18 September 2023

Abstract The development of thermal stress in the exhaust manifold of a gasoline engine is considered. The problem is addresses in the frame of a combined approach where fluid and structure are coupled using the GT-POWER and STAR-CCM+ software. First, the external characteristic curve of the engine is compared with a one-dimensional simulation model, then the parameters of the model are modified until the curve matches the available experimental values. GT-POWER is then used to transfer the inlet boundary data under transient conditions to STAR-CCM+ in real-time. The temperature profiles of the inner and outer walls More >

Ge Kang^1,*, Qiumeng Ouyang¹, Pengwan Chen¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.010508

Abstract It is of great significance to study the dynamic mechanical response of explosive charge to ensure the safety and reliability of weapon system. The manifold method is a novel numerical theory proposed in recent years to simulate the static and dynamic mechanical behavior of solid material. In the present work, a threedimensional numerical manifold software (3D-NMM) based on continuous-discontinuous coupled theory is developed to solve the impact response of PBX. Firstly, based on the 3D finite element topology, a four-node tetrahedral coverage system is established, and the shape function and displacement function, element stiffness matrix… More >

Qiumeng Ouyang¹, Ge Kang^1,*, Pengwan Chen^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.3, pp. 1-1, 2023, DOI:10.32604/icces.2023.010514

Abstract Impact phenomenon is a complicated mechanical problems frequently encountered in our daily life, especially in the military field. Numerical manifold method (NMM) is a novel numerical theory which is proposed based on dual-topology to solve the continuous-discontinues displacement field in both static and dynamic mechanical problems. In the present work, the 3D-NMM program framework enriched with the cover-based contact theory is developed to simulate the impact mechanical problems. Classic Taylor rod experiments with different length-diameter ratios and hitting velocities (150-250m/s) are systematic conducted with ourselves code. The simulation shows that as the impact speed increasing, More >

Loc Vu-Quoc^1,*, Alexander Humer²

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.2, pp. 1069-1343, 2023, DOI:10.32604/cmes.2023.028130 - 26 June 2023

Abstract Three recent breakthroughs due to AI in arts and science serve as motivation: An award winning digital image, protein folding, fast matrix multiplication. Many recent developments in artificial neural networks, particularly deep learning (DL), applied and relevant to computational mechanics (solid, fluids, finite-element technology) are reviewed in detail. Both hybrid and pure machine learning (ML) methods are discussed. Hybrid methods combine traditional PDE discretizations with ML methods either (1) to help model complex nonlinear constitutive relations, (2) to nonlinearly reduce the model order for efficient simulation (turbulence), or (3) to accelerate the simulation by predicting… More >

Yuncong Peng^1,2, Xiaolin Qin^1,2,*, Qianlei Wang^1,2, Boyi Fu^1,2, Yongxiang Gu^1,2

Computer Systems Science and Engineering, Vol.46, No.1, pp. 1233-1247, 2023, DOI:10.32604/csse.2023.032633 - 20 January 2023

Abstract At present, deep learning has been well applied in many fields. However, due to the high complexity of hypothesis space, numerous training samples are usually required to ensure the reliability of minimizing experience risk. Therefore, training a classifier with a small number of training examples is a challenging task. From a biological point of view, based on the assumption that rich prior knowledge and analogical association should enable human beings to quickly distinguish novel things from a few or even one example, we proposed a dynamic analogical association algorithm to make the model use only More >

Chong Wang¹, Tongxing Zuo^1,2, Haitao Han^1,2, Qianglong Wang^1,2, Han Zhang¹, Zhenyu Liu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.1, pp. 655-683, 2023, DOI:10.32604/cmes.2023.025153 - 05 January 2023

Abstract This paper presents an extended sequential element rejection and admission (SERA) topology optimization method with a region partitioning strategy. Based on the partitioning of a design domain into solid regions and weak regions, the proposed optimization method sequentially implements finite element analysis (FEA) in these regions. After standard FEA in the solid regions, the boundary displacement of the weak regions is constrained using the numerical solution of the solid regions as Dirichlet boundary conditions. This treatment can alleviate the negative effect of the material interpolation model of the topology optimization method in the weak regions, More > Graphic Abstract

Zhengtao Xi¹, Chaofan Song², Jiahui Zheng³, Haifeng Shi³, Zhuqing Jiao^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.3, pp. 2243-2266, 2023, DOI:10.32604/cmes.2023.023544 - 23 November 2022

Abstract The structure and function of brain networks have been altered in patients with end-stage renal disease (ESRD). Manifold regularization (MR) only considers the pairing relationship between two brain regions and cannot represent functional interactions or higher-order relationships between multiple brain regions. To solve this issue, we developed a method to construct a dynamic brain functional network (DBFN) based on dynamic hypergraph MR (DHMR) and applied it to the classification of ESRD associated with mild cognitive impairment (ESRDaMCI). The construction of DBFN with Pearson’s correlation (PC) was transformed into an optimization model. Node convolution and hyperedge convolution… More > Graphic Abstract

Jiye Zhang, Huichang Yu, Honghua Dai^*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.1, pp. 5-43, 2023, DOI:10.32604/cmes.2022.022585 - 29 September 2022

Abstract The Moon is the only celestial body that human beings have visited. The design of the Earth-Moon transfer orbits is a critical issue in lunar exploration missions. In the 21st century, new lunar missions including the construction of the lunar space station, the permanent lunar base, and the Earth-Moon transportation network have been proposed, requiring low-cost, expansive launch windows and a fixed arrival epoch for any launch date within the launch window. The low-energy and low-thrust transfers are promising strategies to satisfy the demands. This review provides a detailed landscape of Earth-Moon transfer trajectory design More >

Xiaowei Nie¹, Lihui Ma^2,*, Yiqiu Xu³, Dong Sun², Weibo Zheng², Liang Zhou², Xiaodong Wang², Xiaohan Zhang², Weijia Dong², Yunfei Li²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.1, pp. 37-50, 2023, DOI:10.32604/fdmp.2023.021118 - 02 August 2022

Abstract An experimental study was conducted to investigate the properties of stratified regular or wavy two-phase flow in two parallel separators located after a manifold. A total of 103 experiments with various gas and liquid velocity combinations in three inlet pipes were conducted, including 77 groups of outlet pipe resistance symmetry and 26 groups of outlet pipe resistance asymmetry trials. The experimental results have revealed that when the gas-liquid flow rate is low, the degree of uneven splitting is high, and “extreme” conditions are attained. When the superficial gas velocity is greater than that established in More >