Muhammad Shoaib Arif^1,2,*, Kamaleldin Abodayeh¹, Yasir Nawaz²

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.2, pp. 1213-1241, 2024, DOI:10.32604/cmes.2024.054819 - 27 September 2024

Abstract Fractal time-dependent issues in fluid dynamics provide a distinct difficulty in numerical analysis due to their complex characteristics, necessitating specialized computing techniques for precise and economical solutions. This study presents an innovative computational approach to tackle these difficulties. The main focus is applying the Fractal Runge-Kutta Method to model the time-dependent magnetohydrodynamic (MHD) Newtonian fluid with rescaled viscosity flow on Riga plates. An efficient computational scheme is proposed for handling fractal time-dependent problems in flow phenomena. The scheme is comprised of three stages and constructed using three different time levels. The stability of the scheme… More >

Sonal Nirwal^1,3,*, Ernian Pan^1,2,*, Chih-Ping Lin^1,2, Quoc Kinh Tran¹

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.2, pp. 1165-1191, 2024, DOI:10.32604/cmes.2024.054255 - 27 September 2024

Abstract Magneto-electro-elastic (MEE) materials are a specific class of advanced smart materials that simultaneously manifest the coupling behavior under electric, magnetic, and mechanical loads. This unique combination of properties allows MEE materials to respond to mechanical, electric, and magnetic stimuli, making them versatile for various applications. This paper investigates the static and time-harmonic field solutions induced by the surface load in a three-dimensional (3D) multilayered transversally isotropic (TI) linear MEE layered solid. Green’s functions corresponding to the applied uniform load (in both horizontal and vertical directions) are derived using the Fourier-Bessel series (FBS) system of vector… More >

Xiao Sun¹, Huifan Huang¹, Yuliang Zhang², Lianghuai Tong^3,*, Xiaowei Xu², Xiaoqi Jia⁴, Litao Ou⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.10, pp. 2251-2264, 2024, DOI:10.32604/fdmp.2024.050997 - 23 September 2024

Abstract In order to obtain the transient characteristics of a low-speed centrifugal pump during the start-up and shutdown stages, dedicated experimental tests were conducted with eight different valve opening conditions. The Pearson correlation coefficient was used to reveal the linear correlation between variables. According to the results, the stable rotational speed decreases with increasing valve opening (rotational speed decreases from approximately 1472 to 1453 r/min), while the stable shaft power exhibits an increasing trend (shaft power increases from approximately 0.242 to 0.390 kW). The stable time and zeroing time of each parameter during start-up and shutdown More >

Lianhua Ma¹, Min Huang¹, Linfeng Han^2,*

Structural Durability & Health Monitoring, Vol.18, No.6, pp. 853-869, 2024, DOI:10.32604/sdhm.2024.051374 - 20 September 2024

Abstract Given the complexities of reinforced soil materials’ constitutive relationships, this paper compares reinforced soil composite materials to a sliding structure between steel bars and soil and proposes a reinforced soil constitutive model that takes this sliding into account. A finite element dynamic time history calculation software for composite response analysis was created using the Fortran programming language, and time history analysis was performed on reinforced soil retaining walls and gravity retaining walls. The vibration time histories of reinforced soil retaining walls and gravity retaining walls were computed, and the dynamic reactions of the two types More >

Tianfei Yang¹, Xianyi Long^2,*

International Journal of Mental Health Promotion, Vol.26, No.9, pp. 719-730, 2024, DOI:10.32604/ijmhp.2024.053705 - 20 September 2024

Abstract Background: Though the COVID-19 pandemic recedes, and our society gradually returns to normal, Chinese people’s work and lifestyles are still influenced by the “pandemic aftermath”. In the post-pandemic era, employees may feel uncertainty at work due to the changed organizational operations and management and perceive the external environment to be more dynamic. Both these perceptions may increase employees’ negative emotions and contribute to conflicts between work and life. Drawing from the ego depletion theory, this study aimed to examine the impact of job insecurity during the post-pandemic era on employees’ work-life conflicts, and the mediating… More >

Sen Cui¹, Mengyao Xu¹

Revista Internacional de Métodos Numéricos para Cálculo y Diseño en Ingeniería, Vol.40, No.2, pp. 1-5, 2024, DOI:10.23967/j.rimni.2024.05.015 - 18 June 2024

Abstract Momentum shift is an important sign of nonadiabatic tunnelling ionization process, to investigate the mechanism of momentum shift, we use the strong-field approximation theory to track the formation of ionization momentum spectra of hydrogen atom under the action of different laser pulses in time domain. By observing the ionization momentum spectra of different structures with time, we find that the momentum shift is formed by the continuous interference and evolution of ionization signals over time. Meanwhile, we further analyze how subcycle and intercycle interference influencing the formation of momentum shift. Before the duration is long More >

Abdullah Alabdulatif¹, Navod Neranjan Thilakarathne^2,*, Mohamed Aashiq^3,*

CMC-Computers, Materials & Continua, Vol.80, No.3, pp. 3655-3683, 2024, DOI:10.32604/cmc.2024.054610 - 12 September 2024

Abstract The increasing prevalence of Internet of Things (IoT) devices has introduced a new phase of connectivity in recent years and, concurrently, has opened the floodgates for growing cyber threats. Among the myriad of potential attacks, Denial of Service (DoS) attacks and Distributed Denial of Service (DDoS) attacks remain a dominant concern due to their capability to render services inoperable by overwhelming systems with an influx of traffic. As IoT devices often lack the inherent security measures found in more mature computing platforms, the need for robust DoS/DDoS detection systems tailored to IoT is paramount for… More >

Tajim Md. Niamat Ullah Akhund^1,2,*, Waleed M. Al-Nuwaiser³

CMC-Computers, Materials & Continua, Vol.80, No.3, pp. 3485-3506, 2024, DOI:10.32604/cmc.2024.054222 - 12 September 2024

Abstract This study explores the impact of hyperparameter optimization on machine learning models for predicting cardiovascular disease using data from an IoST (Internet of Sensing Things) device. Ten distinct machine learning approaches were implemented and systematically evaluated before and after hyperparameter tuning. Significant improvements were observed across various models, with SVM and Neural Networks consistently showing enhanced performance metrics such as F1-Score, recall, and precision. The study underscores the critical role of tailored hyperparameter tuning in optimizing these models, revealing diverse outcomes among algorithms. Decision Trees and Random Forests exhibited stable performance throughout the evaluation. While More >

Biru Chang^1,*, Shengqiang Zhu², Qian Xie^3,4, Yanghui Dai⁵

International Journal of Mental Health Promotion, Vol.26, No.8, pp. 599-610, 2024, DOI:10.32604/ijmhp.2024.050302 - 30 August 2024

Abstract Background: With public health emergencies (PHE) worldwide increasing, the perceived risk of PHE has been one of the critical factors influencing college students’ psychological distress. However, the mechanisms by which the perceived risk of PHE affects college students’ psychological distress are not clear. The study’s purpose was to investigate the mediation roles of deviation from a balanced time perspective (DBTP) and negative coping styles between the perceived risk of PHE and psychological distress. Methods: A convenience sampling method was used to survey 1054 Chinese college students with self-reporting. Data was collected using the Public Risk… More >

Matiewos Mekonen Abera^1,2,*, Venkata Ramayya Ancha¹, Balewgize Amare¹, L. Syam Sundar³, Kotturu V. V. Chandra Mouli⁴, Sambasivam Sangaraju⁵

Frontiers in Heat and Mass Transfer, Vol.22, No.4, pp. 1043-1070, 2024, DOI:10.32604/fhmt.2024.049525 - 30 August 2024

Abstract This study is focused on the simulation and optimization of packed-bed solar thermal energy storage by using sand as a storage material and hot-water is used as a heat transfer fluid and storage as well. The analysis has been done by using the COMSOL multi-physics software and used to compute an optimization charging time of the storage. Parameters that control this optimization are storage height, storage diameter, heat transfer fluid flow rate, and sand bed particle size. The result of COMSOL multi-physics optimized thermal storage has been validated with Taguchi method. Accordingly, the optimized parameters… More >