Xinyu Hu, Defeng Kong^*, Xiyang Liu, Junwei Zhang, Daode Zhang

CMC-Computers, Materials & Continua, Vol.78, No.1, pp. 915-933, 2024, DOI:10.32604/cmc.2023.046376

Abstract Printed Circuit Board (PCB) surface tiny defect detection is a difficult task in the integrated circuit industry, especially since the detection of tiny defects on PCB boards with large-size complex circuits has become one of the bottlenecks. To improve the performance of PCB surface tiny defects detection, a PCB tiny defects detection model based on an improved attention residual network (YOLOX-AttResNet) is proposed. First, the unsupervised clustering performance of the K-means algorithm is exploited to optimize the channel weights for subsequent operations by feeding the feature mapping into the SENet (Squeeze and Excitation Network) attention network; then the improved K-means-SENet… More >

Xingwang Li^1,2, Hua Pang¹, Geng Li^1,*, Junjie Jiang¹, Hui Zhang³, Changfei Gu⁴, Dong Yuan⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1135-1166, 2024, DOI:10.32604/cmes.2023.031534

Abstract The development of the fifth-generation (5G) mobile communication systems has entered the commercialization stage. 5G has a high data rate, low latency, and high reliability that can meet the basic demands of most industries and daily life, such as the Internet of Things (IoT), intelligent transportation systems, positioning, and navigation. The continuous progress and development of society have aroused wide concern. Positioning accuracy is the core demand for the applications, especially in complex environments such as airports, warehouses, supermarkets, and basements. However, many factors also affect the accuracy of positioning in those environments, for example, multipath effects, non-line-of-sight, and clock… More >

Zhengqing Ding, Quan Yang, Xinyan Yan, Feng Gu, Xujuan Huang^*, Zhaosheng Cai^*

Journal of Renewable Materials, Vol.12, No.1, pp. 103-117, 2024, DOI:10.32604/jrm.2023.029424

Abstract Dehydroabietyl polyethylene glycol glycidyl ether-grafted hydroxyethyl cellulose (HEC) polymer surfactant (DA(EO)₅GE-g-HEC) was prepared using ring-opening polymerization with biobased rosin and hydroxyethyl cellulose as feedstocks. Dehydroabietyl polyethylene glycol glycidyl ether (DA(EO)₅GE) was formed by condensation of dehydroabietyl alcohol polyoxyethylene ether (Rosin derivative: DA(EO)₅H) and epichlorohydrin. The grafting degree of DA(EO)₅GE-g-HEC was manipulated by adjusting the mass ratio of HEC and DA(EO)₅GE and confirmed by EA. According to the formula, when m_(HEC)/m_(DA(EO)2GE) was 1:1~1:5, the grafting rate of DA(EO)₅GE in DA(EO)₅GE-g-HEC varied from 34.43% to 38.33%. The surface activity and foam properties of DA(EO)₅GE-g-HEC aqueous solution were studied. The results showed that… More > Graphic Abstract

Xudong Chen^1,2, Quanzi Yuan^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.09318

Abstract The wetting and instability of liquids on the surface of soluble solids is a problem of interface stability at multiple scales, which is coupled by mechanics and chemistry. This problem is crucial to application fields such as micro-nano processing and microscopic observation. In this work, the instability process of moving contact lines on the surfaces of soluble solids is investigated in experiments, theories, and simulations. Based on the unique shapes of the surfaces of soluble solids caused by instability in experiments, the concept of pagoda instability is proposed. Then the Cahn-Hilliard interfaces are developed to establish the evolution model of… More >

Shan Xu^1,*, Huadu Tang¹, Ding Wang¹, Ruiguang Zhu¹, Liwei Wang¹, Shengwang Hao¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-3, 2023, DOI:10.32604/icces.2023.09930

Abstract Damage evaluation is an important index for the evaluation of buildings health. To provide a rapid crack evaluation in practical applications, a crack identification and damage evaluation via deep learning framework is proposed in this paper. We built a combined dataset from Kaggle and site photos. A pre-trained U-net model is used to perform the training of model. With updated weights, the identification of cracks could be performed on non-labelled photos. More >

Zhuoma Wang¹, Ruoyan Li^2,3, Wenjing Ye^2,*, Yijun Liu³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09236

Abstract An acoustic diffuser refers to a device that spreads sound energy uniformly in all directions. Such a device plays a very important role in architectural acoustics, i.e., concert halls and auditoriums. Many designs such as the wellknown Schroeder diffusers [1] have been proposed and developed throughout the past several decades. However, most of these conventional designs achieve uniform sound diffusion by using different air trenches to create a phase shift profile following a specific sequence such as maximum length sequence or quadratic residue sequence derived from the number theory [1,2]. As such, these diffusers have considerable thicknesses, which makes them… More >

Aaqib Majeed^1,*, Ahmad Zeeshan²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 525-536, 2024, DOI:10.32604/fdmp.2023.028716

Abstract The influence of Brownian motion and thermophoresis on a fluid containing nanoparticles flowing over a stretchable cylinder is examined. The classical Navier-Stokes equations are considered in a porous frame. In addition, the Lorentz force is taken into account. The controlling coupled nonlinear partial differential equations are transformed into a system of first order ordinary differential equations by means of a similarity transformation. The resulting system of equations is solved by employing a shooting approach properly implemented in MATLAB. The evolution of the boundary layer and the growing velocity is shown graphically together with the related profiles of concentration and temperature.… More >

Chuang Lu¹, Leilei Chen^2,3, Jinling Luo⁴, Haibo Chen^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 847-872, 2024, DOI:10.32604/cmes.2023.044446

Abstract We propose a combined shape and topology optimization approach in this research for 3D acoustics by using the isogeometric boundary element method with subdivision surfaces. The existing structural optimization methods mainly contain shape and topology schemes, with the former changing the surface geometric profile of the structure and the latter changing the material distribution topology or hole topology of the structure. In the present acoustic performance optimization, the coordinates of the control points in the subdivision surfaces fine mesh are selected as the shape design parameters of the structure, the artificial density of the sound absorbing material covered on the… More >

Puja S. Prasad¹, Adepu Sree Lakshmi¹, Sandeep Kautish², Simar Preet Singh³, Rajesh Kumar Shrivastava³, Abdulaziz S. Almazyad⁴, Hossam M. Zawbaa⁵, Ali Wagdy Mohamed^6,7,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 725-739, 2024, DOI:10.32604/cmes.2023.030640

Abstract Pupil dynamics are the important characteristics of face spoofing detection. The face recognition system is one of the most used biometrics for authenticating individual identity. The main threats to the facial recognition system are different types of presentation attacks like print attacks, 3D mask attacks, replay attacks, etc. The proposed model uses pupil characteristics for liveness detection during the authentication process. The pupillary light reflex is an involuntary reaction controlling the pupil’s diameter at different light intensities. The proposed framework consists of two-phase methodologies. In the first phase, the pupil’s diameter is calculated by applying stimulus (light) in one eye… More >

Liuyi Ling^1,2,3, Yiwen Wang^1,*, Fan Ding⁴, Li Jin¹, Bin Feng³, Weixiao Li³, Chengjun Wang¹, Xianhua Li¹

CMC-Computers, Materials & Continua, Vol.77, No.3, pp. 2771-2790, 2023, DOI:10.32604/cmc.2023.043383

Abstract Surface electromyography (sEMG) is widely used for analyzing and controlling lower limb assisted exoskeleton robots. Behavior intention recognition based on sEMG is of great significance for achieving intelligent prosthetic and exoskeleton control. Achieving highly efficient recognition while improving performance has always been a significant challenge. To address this, we propose an sEMG-based method called Enhanced Residual Gate Network (ERGN) for lower-limb behavioral intention recognition. The proposed network combines an attention mechanism and a hard threshold function, while combining the advantages of residual structure, which maps sEMG of multiple acquisition channels to the lower limb motion states. Firstly, continuous wavelet transform… More >