Taha Yacine Trad^1,*, Kheireddine Choutri¹, Mohand Lagha¹, Souham Meshoul², Fouad Khenfri³, Raouf Fareh⁴, Hadil Shaiba⁵

CMC-Computers, Materials & Continua, Vol.81, No.3, pp. 4757-4786, 2024, DOI:10.32604/cmc.2024.055634 - 19 December 2024

Abstract The popularity of quadrotor Unmanned Aerial Vehicles (UAVs) stems from their simple propulsion systems and structural design. However, their complex and nonlinear dynamic behavior presents a significant challenge for control, necessitating sophisticated algorithms to ensure stability and accuracy in flight. Various strategies have been explored by researchers and control engineers, with learning-based methods like reinforcement learning, deep learning, and neural networks showing promise in enhancing the robustness and adaptability of quadrotor control systems. This paper investigates a Reinforcement Learning (RL) approach for both high and low-level quadrotor control systems, focusing on attitude stabilization and position… More >

Yuri Ivochkin¹, Igor Teplyakov¹, Oleg Sinkevich^1,2, Sergei Shchigel¹, Stepan Yudin^1,2,*

Frontiers in Heat and Mass Transfer, Vol.22, No.6, pp. 1805-1821, 2024, DOI:10.32604/fhmt.2024.056787 - 19 December 2024

Abstract This study explores the mechanism behind the generation of pressure pulses on the outer surface of a molten metal droplet when immersed in water. The absence of any external trigger is assumed, and the droplet is surrounded by a vapor layer with surface hydrodynamic waves at the vapor-liquid interface. The study examines the heating conditions of a cylindrical column of water used to model a volume of cold liquid interacting with a hot metal surface, which explosively boils upon direct contact. Within the framework of classical homogeneous nucleation theory, the relationship between pressure pulse magnitude… More >

Guochen Ding¹, Jing Zhang¹, Shurong Ding^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.32, No.1, pp. 1-1, 2024, DOI:10.32604/icces.2024.011410

Abstract Zirconium alloys have high strength, high corrosion resistance and low neutron absorption cross section, widely served as the nuclear cladding tubes or some other structural components. During the storage stage of spent fuels or in the lower-temperature reactor-core locations, the hydrogen atoms within the zirconium alloy components would diffuse to the crack tip owing to stress concentration, possibly initiating delayed hydride cracking (DHC) and posing a potential threat to nuclear safety. In this study, the CDM (continuum damage mechanics)-based multi-field coupling computational models are developed, with the hydride-induced hardening and embrittlement, hydride orientation contributions and… More >

Muhammad Tashfeen¹, Fazal Dayan¹, Muhammad Aziz ur Rehman¹, Thabet Abdeljawad^2,3,4,5,*, Aiman Mukheimer²

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.3, pp. 2527-2554, 2024, DOI:10.32604/cmes.2024.056269 - 31 October 2024

Abstract Foot-and-mouth disease (FMD) is a viral disease that affects cloven-hoofed animals including cattle, pigs, and sheep, hence causing export bans among others, causing high economic losses due to reduced productivity. The global effect of FMD is most felt where livestock rearing forms an important source of income. It is therefore important to understand the modes of transmission of FMD to control its spread and prevent its occurrence. This work intends to address these dynamics by including the efficacy of active migrant animals transporting the disease from one area to another in a fuzzy mathematical modeling… More >

Muhammad Tashfeen¹, Fazal Dayan¹, Muhammad Aziz Ur Rehman¹, Thabet Abdeljawad^2,3,4,5,*, Aiman Mukheimer²

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.2, pp. 1419-1446, 2024, DOI:10.32604/cmes.2024.053242 - 27 September 2024

Abstract This study analyzes the transmission of typhoid fever caused by Salmonella typhi using a mathematical model that highlights the significance of delay in its effectiveness. Time delays can affect the nature of patterns and slow down the emergence of patterns in infected population density. The analyzed model is expanded with the equilibrium analysis, reproduction number, and stability analysis. This study aims to establish and explore the non-standard finite difference (NSFD) scheme for the typhoid fever virus transmission model with a time delay. In addition, the forward Euler method and Runge-Kutta method of order 4 (RK-4)… More >

Umar Shafique^1,*, Mohamed Mahyoub Al-Shamiri², Ali Raza³, Emad Fadhal^4,*, Muhammad Rafiq^5,6, Nauman Ahmed^5,7

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.1, pp. 311-329, 2024, DOI:10.32604/cmes.2024.052383 - 20 August 2024

Abstract Based on the World Health Organization (WHO), Meningitis is a severe infection of the meninges, the membranes covering the brain and spinal cord. It is a devastating disease and remains a significant public health challenge. This study investigates a bacterial meningitis model through deterministic and stochastic versions. Four-compartment population dynamics explain the concept, particularly the susceptible population, carrier, infected, and recovered. The model predicts the nonnegative equilibrium points and reproduction number, i.e., the Meningitis-Free Equilibrium (MFE), and Meningitis-Existing Equilibrium (MEE). For the stochastic version of the existing deterministic model, the two methodologies studied are transition… More >

Ali Alshahrani¹, Ahmad Adel Abu-Shareha^2,*, Qusai Y. Shambour², Basil Al-Kasasbeh¹

CMC-Computers, Materials & Continua, Vol.77, No.2, pp. 1679-1698, 2023, DOI:10.32604/cmc.2023.043545 - 29 November 2023

Abstract Active queue management (AQM) methods manage the queued packets at the router buffer, prevent buffer congestion, and stabilize the network performance. The bursty nature of the traffic passing by the network routers and the slake behavior of the existing AQM methods leads to unnecessary packet dropping. This paper proposes a fully adaptive active queue management (AAQM) method to maintain stable network performance, avoid congestion and packet loss, and eliminate unnecessary packet dropping. The proposed AAQM method is based on load and queue length indicators and uses an adaptive mechanism to adjust the dropping probability based… More >

Farman Ali¹, Khalid Zaman², Babar Shah³, Tariq Hussain⁴, Habib Ullah⁵, Altaf Hussain⁵, Daehan Kwak^6,*

CMC-Computers, Materials & Continua, Vol.77, No.1, pp. 963-981, 2023, DOI:10.32604/cmc.2023.040628 - 31 October 2023

Abstract The paper presents a new protocol called Link Stability and Transmission Delay Aware (LSTDA) for Flying Ad-hoc Network (FANET) with a focus on network corridors (NC). FANET consists of Unmanned Aerial Vehicles (UAVs) that face challenges in avoiding transmission loss and delay while ensuring stable communication. The proposed protocol introduces a novel link stability with network corridors priority node selection to check and ensure fair communication in the entire network. The protocol uses a Red-Black (R-B) tree to achieve maximum channel utilization and an advanced relay approach. The paper evaluates LSTDA in terms of End-to-End More >

Sikandar Khan¹, Khalid Saeed¹, Muhammad Faran Majeed^2,*, Salman A. AlQahtani³, Khursheed Aurangzeb³, Muhammad Shahid Anwar^4,*

CMC-Computers, Materials & Continua, Vol.77, No.1, pp. 1303-1323, 2023, DOI:10.32604/cmc.2023.039697 - 31 October 2023

Abstract Delay Tolerant Networks (DTNs) have the major problem of message delay in the network due to a lack of end-to-end connectivity between the nodes, especially when the nodes are mobile. The nodes in DTNs have limited buffer storage for storing delayed messages. This instantaneous sharing of data creates a low buffer/shortage problem. Consequently, buffer congestion would occur and there would be no more space available in the buffer for the upcoming messages. To address this problem a buffer management policy is proposed named “A Novel and Proficient Buffer Management Technique (NPBMT) for the Internet of… More >

Shengyao Sun^1,2, Ying Du³, Jiajun Chen⁴, Xuan Zhang⁵, Jiwei Zhang^6,*, Yiyi Xu⁷

CMC-Computers, Materials & Continua, Vol.76, No.3, pp. 2879-2900, 2023, DOI:10.32604/cmc.2023.037483 - 08 October 2023

Abstract In Multi-access Edge Computing (MEC), to deal with multiple user equipment (UE)’s task offloading problem of parallel relationships under the multi-constraints, this paper proposes a cooperation partial task offloading method (named CPMM), aiming to reduce UE's energy and computation consumption, while meeting the task completion delay as much as possible. CPMM first studies the task offloading of single-UE and then considers the task offloading of multi-UE based on single-UE task offloading. CPMM uses the critical path algorithm to divide the modules into key and non-key modules. According to some constraints of UE-self when offloading tasks,… More >