An Chen^*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 173-195, 2020, DOI:10.32604/cmes.2020.011871 - 18 September 2020

Abstract In this paper, we consider the numerical schemes for a timefractional Oldroyd-B fluid model involving the Caputo derivative. We propose two efficient finite element methods by applying the convolution quadrature in time generated by the backward Euler and the second-order backward difference methods. Error estimates in terms of data regularity are established for both the semidiscrete and fully discrete schemes. Numerical examples for two-dimensional problems further confirm the robustness of the schemes with first- and second-order accurate in time. More >

Dan Li¹, Li Ding¹, Zhengang Liu², Qiang Li³, Kaiyun Guo¹, Hailin Cao^1,4,*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 145-171, 2020, DOI:10.32604/cmes.2020.010822 - 18 September 2020

Abstract Carbon nanotube (CNT)-reinforced composites have ultra-high elastic moduli, low densities, and fibrous structures. This paper presents the multi-scale finite element modeling of CNT-reinforced polymer composites from micro- to macro-scales. The nanocomposites were modeled using representative volume elements (RVEs), and finite element code was written to simulate the modeling and loading procedure and obtain equivalent mechanical properties of the RVEs with various volume fractions of CNTs, which can be used directly in the follow-up simulation studies on the macroscopic model of CNT-reinforced nanocomposites. When using the programming to simulate the deformation and fracture process of the… More >

G. R. Hemalakshmi^*, D. Santhi, V. R. S. Mani, A. Geetha, N. B. Prakash

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 125-143, 2020, DOI:10.32604/cmes.2020.011331 - 18 September 2020

Abstract Diabetic retinopathy, aged macular degeneration, glaucoma etc. are widely prevalent ocular pathologies which are irreversible at advanced stages. Machine learning based automated detection of these pathologies facilitate timely clinical interventions, preventing adverse outcomes. Ophthalmologists screen these pathologies with fundus Fluorescein Angiography Images (FFA) which capture retinal components featuring diverse morphologies such as retinal vasculature, macula, optical disk etc. However, these images have low resolutions, hindering the accurate detection of ocular disorders. Construction of high resolution images from these images, by super resolution approaches expedites the diagnosis of pathologies with better accuracy. This paper presents a More >

Jia Yang¹, Haiyuan Liu^1,*, Hao He²

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 111-123, 2020, DOI:10.32604/cmes.2020.010347 - 18 September 2020

Abstract The prediction of intrinsically disordered proteins is a hot research area in bio-information. Due to the high cost of experimental methods to evaluate disordered regions of protein sequences, it is becoming increasingly important to predict those regions through computational methods. In this paper, we developed a novel scheme by employing sequence complexity to calculate six features for each residue of a protein sequence, which includes the Shannon entropy, the topological entropy, the sample entropy and three amino acid preferences including Remark 465, Deleage/Roux, and Bfactor(2STD). Particularly, we introduced the sample entropy for calculating time series… More >

Jianrui Zhang^1,2, Min Chi¹, Bo Qian^1,*, Zhijun Qiu²

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 77-94, 2020, DOI:10.32604/cmes.2020.010518 - 18 September 2020

Abstract To accurately perform the coupled simulation of temperature field and stress field of complex parts and porous structures under the optimal manufacturing process parameters, three kinds of porous structures with different complexity were designed in this paper. Firstly, ANSYS additive software was used to conduct the stress/deformation simulation of the whole structure under different scanning strategies. Secondly, the optimal scanning strategy for different porous structures was determined, then the experimental preparation was performed, and mechanical properties of compression were tested and studied. The results show that the elastic modulus and yield strength increase with the More >

Fabio Bruzzone, Cristiana Delprete, Carlo Rosso^*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 51-64, 2020, DOI:10.32604/cmes.2020.011023 - 18 September 2020

Abstract This paper is focused on finite element simulation of cylinder head gaskets. Finite element codes support several methodologies, each of which has its own strengths and weaknesses. One of the key points lies in the influence of the gasket geometry on its final behaviour. Such a contribution can come from the detailed modelling of the gasket or by defining a global non-linear behaviour in which material and geometry non-linearities are summarised. Two approaches were used to simulate the gasket behaviour. The first one consists in using a 2D approach, which allows to model through-thickness non-linear More >

Hui Sheng Lim^1,*, Christopher K. H. Chin¹, Shuhong Chai¹, Neil Bose^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 33-50, 2020, DOI:10.32604/cmes.2020.011648 - 18 September 2020

Abstract This paper presents an online AUV (autonomous underwater vehicle) path planner that employs path replanning approach and the SDEQPSO (selective differential evolution-hybridized quantum-behaved particle swarm optimization) algorithm to optimize an AUV mission conducted in an unknown, dynamic and cluttered ocean environment. The proposed path replanner considered the effect of ocean currents in path optimization to generate a Pareto-optimal path that guides the AUV to its target within minimum time. The optimization was based on the onboard sensor data measured from the environment, which consists of a priori unknown dynamic obstacles and spatiotemporal currents. Different sensor… More >

Mohammad Maghsoudi-Ganjeh, Xiaodu Wang^*, Xiaowei Zeng^*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 1-32, 2020, DOI:10.32604/cmes.2020.012123 - 18 September 2020

Abstract In this review, a brief presentation is first given to the hierarchical structure and mechanical behavior of bone. Then, the recent advancements in nanoscale characterization of bone ultrastructure and ingredients are discussed based on an extensive quantity of references in the literature.Moreover, computational and analytical bone mechanics at ultrastructure levels are critically reviewed with the growing body of knowledge in the field. The computational and analytical models are summarized in several categories for ease of understanding bone nanomechanics and their applicability/limitations. This review is expected to provide a well-informed foundation for the researchers interested in More >

Xuguang Liu¹, Ruqing Zhao², Qifei Chen², Ming Shi³, Ziling Xing², Yanan Zhang^4,*

Journal on Big Data, Vol.2, No.2, pp. 85-93, 2020, DOI:10.32604/jbd.2020.013845 - 18 September 2020

Abstract The shooting state during shooting refers to the basketball’s shooting speed, shooting angle and the ball’s rotation speed. The basketball flight path is also related to these factors. In this paper, based on the three forces of Gravity, Air Resistance and Magnus Force, the “Three Forces” model is established, the Kinetic equations are derived, the basketball flight trajectory is solved by simulation, and the best shot state when shooting is obtained through the shooting percentage. Compared with the “Single Force” model that only considers Gravity, the shooting percentage of the “Three Forces” model is higher. More >

Kai Chen^1,*, Haoqi Zhu², Leiming Yan¹, Jinwei Wang¹

Journal on Big Data, Vol.2, No.2, pp. 71-84, 2020, DOI:10.32604/jbd.2020.012294 - 18 September 2020

Abstract Adversarial examples are hot topics in the field of security in deep learning. The feature, generation methods, attack and defense methods of the adversarial examples are focuses of the current research on adversarial examples. This article explains the key technologies and theories of adversarial examples from the concept of adversarial examples, the occurrences of the adversarial examples, the attacking methods of adversarial examples. This article lists the possible reasons for the adversarial examples. This article also analyzes several typical generation methods of adversarial examples in detail: Limited-memory BFGS (L-BFGS), Fast Gradient Sign Method (FGSM), Basic… More >