Najran University

In this article, we study the fractional form of a well-known dynamical system from mathematical biology, namely, the Lotka–Volterra model. This mathematical model describes the dynamics of a predator and a prey, and we consider here the fractional form using the Rabotnov fractional-exponential (RFE) kernel. In this work, we derive an approximate formula of the fractional derivative of a power function t p in terms of the RFE kernel. Next, by using the spectral collocation method (SCM) based on the shifted Vieta–Lucas polynomials (VLPs), the fractional differential system is reduced to a set of algebraic equations. We provide a theoretical convergence analysis for the numerical approach, and the accuracy is verified by evaluating the residual error function through some concrete examples.

Background Chronic nonspecific neck pain (CNSNP) is a common musculoskeletal disorder, particularly in the elderly, leading to reduced cervical muscle strength, impaired functional balance, and decreased postural stability. This study investigated the correlation between cervical muscle strength, functional balance, and limits of stability (LOS) in elderly individuals with CNSNP. Additionally, it assessed the moderating effect of pain severity on the relationship between cervical muscle strength and these balance outcomes. Methods A prospective study included a total of 186 participants, including 93 with CNSNP and 93 asymptomatic individuals, were recruited. Cervical flexor and extensor muscle strength were assessed using an ergoFET hand-held dynamometer. Functional balance was measured using the Berg Balance Scale (BBS) and Timed Up and Go (TUG) test, while LOS were evaluated using the Iso-Free machine. Results Individuals with CNSNP exhibited significantly lower cervical flexor strength (32.45 ± 5.67 N vs. 40.75 ± 5.20 N, p < 0.001) and extensor strength (28.30 ± 6.05 N vs. 36.90 ± 5.90 N, p < 0.001) compared to asymptomatic individuals. Functional balance was also poorer in the CNSNP group, with lower BBS scores (47.85 ± 4.20 vs. 53.65 ± 3.85, p < 0.001) and slower TUG times (11.30 ± 2.05 s vs. 8.45 ± 1.80 s, p < 0.001). Cervical muscle strength showed moderate to strong positive correlations with LOS (r = 0.56 to 0.62, p < 0.001) and BBS (r = 0.48 to 0.53, p < 0.001). Pain severity significantly moderated the relationship between cervical muscle strength and functional balance (β = 0.20, p = 0.045) as well as LOS (β = 0.22, p = 0.038), suggesting that higher pain levels diminish the positive effects of muscle strength on balance. Conclusion Cervical muscle strength plays a crucial role in maintaining functional balance and postural stability in elderly individuals with CNSNP. Pain severity moderates the relationship between cervical muscle strength and balance outcomes, emphasizing the importance of integrating muscle strengthening and pain management in rehabilitation programs for elderly individuals with CNSNP to optimize postural control and minimize fall risk.

We propose a novel borophene-based metamaterial absorber for ultraviolet (UV) and infrared (IR) applications. This multi-layered structure, composed of borophene, magnesium fluoride, tungsten, silicon, and silver resonators, was numerically analyzed across a broad frequency spectrum (100–2500 THz) using finite element method (FEM) simulations. The absorber’s performance was investigated by varying physical parameters such as layer heights, incident angles, and resonator modes. The structure consistently exhibits over 90% peak absorption at multiple THz frequencies and maintains an average absorption efficiency exceeding 60% within the 200–2500 THz range. Notably, these absorption characteristics remain relatively stable despite variations in physical parameters, with a maximum impact of 5–10% on absorption efficiency. By comparing the absorption spectrum and the standardize AM 1.5 spectrum, we demonstrate the structure’s potential for efficient solar energy harvesting. Moreover, the absorber maintains high absorption efficiency even at oblique angles of incidence up to 60°. This innovative design can be a foundational component for parasitic absorber devices in solar cells and other sensing and ultra-wideband UV and IR absorption applications.

This investigation presents extensive computational analyses of the compressible flow near ramp injector with double circular injectors at supersonic combustor of scramjet engine. Comparison of the fuel mixing and fuel jet penetration of hydrogen jet are done for two injector configurations at free stream Mach number of 2. The simulation of the supersonic flow near ramp injector is done via solving RANS equations with computational fluid dynamic technique. Effect of nozzle space on the fuel distribution and mixing mechanism has been investigated. Besides, interface of the free stream and jet behind the ramp are fully analyzed. Comparison of the circulation strength behind these two configurations indicates that increasing of the jet space led to higher circulation strength. However, the mixing efficiency of the model with low jet space is higher since the interaction of these two jet is key factor for diffusion and mixing inside the combustion chamber.

This study investigates the viability and benefits of utilizing compressed earth blocks (CEBs) as a sustainable construction material under varying climatic conditions, focusing on two cities in Saudi Arabia: Riyadh, representing a hot desert climate, and Abha, representing a cooler, high‐altitude climate. A comprehensive simulation‐based methodology was employed, which included energy performance modeling and optimization using EnergyPlus software, climate data analysis, environmental impact assessment, and cost analysis. To further verify the results, the EnergyPlus simulations were validated using a machine learning model, specifically the gradient boosting regressor (GBR), to ensure accuracy and reliability. The simulations demonstrate that CEBs provide substantial benefits in terms of structural performance, energy efficiency, and sustainability. For instance, CEB buildings showed reduced cooling loads by 35% in Riyadh and 25% in Abha, while also maintaining high indoor air quality and thermal comfort, leading to 80‐85% occupant satisfaction. The use of CEBs contributed to significant reductions in carbon emissions, with 90% renewable materials, and proved to be cost‐effective over the long term. The GBR validation confirmed less than 2% variation from the EnergyPlus simulations, further ensuring the reliability of the results. Environmental impact assessments revealed substantial reductions in carbon emissions, resource consumption, and waste generation through the adoption of CEBs. Although the initial cost of CEBs may be slightly higher than traditional materials, the long‐term energy savings and reduced maintenance costs make them an economically viable option, particularly in regions with extreme climates. This study underscores the potential of CEBs as a versatile, efficient, and sustainable building material, offering significant benefits in energy efficiency, environmental impact reduction, cost‐effectiveness, and occupant comfort—all based on robust simulation and modeling results.

The lifetime and smooth action of petroleum machines is significantly affected by fuel purity. Today, a lot of deceitful dealers mix petroleum products with inferior-priced oils/components to enlarge their earnings. To address these issues, a surface plasmon resonance sensor is projected to discover the presence of kerosene concentration in petrol (gasoline). Newly, angular analyses have been commonly depleted to determine the sensitivity. The present study is proposed for the screening of kerosene concentrations in the fuel using prism coupling-based surface plasmon resonance biosensors. All the analytical works are performed by Mathematica 5.2 software, and the Origin software is expended to plot the graphs. The sensor created on the Kretschmann pattern is made up of the hybrid assembly based on beryllium oxide (BeO) and graphene layers deposited on silver film. The wavelength of the used input wave is 632.8 nm. The top sensitivity of 465.21 degree/RIU has been acquired when the kerosene concentration is 40%. The suggested sensor exhibits an outstanding sensitivity and includes an inclusive scope of the analyte’s refractive indices. As a result, the offered sensor can be an appropriate candidate for chemical sensing purposes.

In this study, we report the synthesis of iron oxide nanoparticles (FeONPs) using micro-emulsion-hydrothermal method. By adjusting the synthesis temperature, we successfully produced FeO nanorods and nanospheres. In addition, the 2-octanol, and the surfactant cetyltrimethylammonium bromide served as a solvent in the synthesis process. Using iron nitrate hexahydrate as the salt precursor allowed for the formation of FeONPs with varied sizes, shapes and phases. The synthesized materials were extensively characterized using XRD, SEM, TEM, EDS, FTIR, and XPS techniques. However, the structural analysis revealed rhombohedral (hematite), and (magnetite) crystal structures in the materials synthesized at different temperature and durations, with particles ranged in size from 12 to 97 nm. More importantly, the magnetic characterization, performed with a vibrating sample magnetometer and SQUID magnetometer, indicated that the NPs showed not clear superparamagnetic behavior. In conclusion, this work demonstrates the synthesis of FeONPs with controlled size, shape and phase using microemulsion hydrothermal technique, with detailed characterization offering valuable insights into their magnetic and structural properties.

In the current years, gas–liquid membrane contactors (GLMCs) have been introduced as a promising, versatile and easy-to-operate technology for mitigating the emission of major greenhouse contaminants (i.e., CO2 and H2S) to the ecosystem. This paper tries to computationally study the role of membrane pores wettability on the removal performance of CO2 inside the HFMC. To fulfill this purpose, a mathematical model based on finite element procedure (FEP) has been employed to solve the momentum and mass transport equations in the partial-wetting (50% wetting of micropores) and non-wetting (0% wetting of micropores) modes of membrane during operation. Additionally, a comprehensive simulation was ensembled to predict the results. In this research, 2-amino-2-methyl-l-propanol (AMP) has been employed as a relatively novel alkanolamine absorbent to separate CO2 form CO2/N2 mixture. Analysis of the results implied that the wetting of membrane micropores significantly deteriorated the removal efficiency due to the enhancing mass transfer resistance towards transferring CO2 (75% in the non-wetting mode > 8% considering 50% wetting of micropores).

There has been a recent trend in research to integrate Science, Technology, Engineering, Arts, and Mathematics (STEAM) into language education curricula to promote bilingualism and multilingualism, addressing the requirements of 21st century skills. However, this emerging issue remains insufficiently synthesized in the language education literature. To address this gap, this study aims to synthesize STEM literature in the context of language education, providing a comprehensiveview of how this issue has been researched and identifying trending research themes and hotspot research issues. Thirty-nine studies were selected from meticulously searched databases including Web of Science, Scopus, and Google Scholar. To visualize the studies’ findings, we employed Python software to illustrate results obtained from the pool of studies and utilized Jupyter Notebook software to generate word clouds. Results reveal a rapid growth in STEAM education research since 2017, with a predominance of qualitative and mixed methods approaches, involving high numbers of participants in the studies’ interventions. Findings also indicated positive outcomes in students’ linguistic and STEM abilities, highlighting bilingualism, multilingualism, and translanguaging as emerging themes that enhance overall STEM literacy and engagement. Writing activities were more frequently employed in the target studies and more prevalent than reading, especially at the college level, while reading was more common in primary and middle schools.

In online learning, many teachers have adopted traditional assessment methods in offline assessments without adequately testing and assessing the consequences. Therefore, this descriptive study aims to identify teachers’ and students’ perceptions of online assessments in evaluating English as a Foreign Language (EFL) students’ learning. A convenient sample of teachers and students was recruited to respond to a questionnaire on their beliefs about and reported use of online assessment methods through management learning systems. Additionally, semi-structured interviews were conducted to explore participants’ experiences with online assessment. The results demonstrated that teachers’ and students’ beliefs regarding online assessments for EFL learning were moderate, indicating a shared but cautious acceptance of these methods. The analysis revealed no significant differences in perceptions based on participants’ roles, suggesting a common understanding of the challenges and benefits of online assessments among educators and learners alike. Qualitative responses highlighted six key themes: the nature of online assessments, time and effort required, performance outcomes, psychological pressure experienced, and overall user experience, reflecting the concerns regarding technological readiness, academic integrity, and the need for more diverse assessment methods. To enhance the effectiveness of online assessments in the EFL context, the study recommends ensuring a robust technological infrastructure, offering comprehensive training for teachers on various online assessment methods, diversifying assessment techniques to capture a broader range of student abilities, and fostering a culture of ethical assessment practices through close monitoring of student work.

The integration of information and communication technology (ICT) into language teaching and learning depends on many factors. Some of these factors are associated with teachers. Teachers play a crucial role in the integration of ICT. This study investigates the impact of teacher's age, experience, and gender on the integration of ICT into language teaching. This study utilized a mixed-method approach of investigation, which applies both qualitative and quantitative methods. The instruments used for data collection were a survey and an interview. The survey was administered to 46 in-service EFL teachers working at Najran University, Saudi Arabia. Ten out of these participants were interviewed. The results indicate that there is no significant difference in using ICT between the two groups of teachers according to their age and experience. However, the results indicate that there is a difference between male and female teachers in using ICT in language teaching. Female teachers reported less use of ICT in their instruction than male teachers. Some suggestions are offered to improve the situation of ICT integration into language learning in EFL contexts.

Background Type 2 diabetes Mellitus (T2DM) increases vulnerability to metabolic dysfunction-associated steatotic liver disease (MASLD). Therefore, this study aims to determine the prevalence and coexistence of MASLD in patients with T2DM using ultrasound. Methods This cross-sectional retrospective study included 168 patients with T2DM from multiple diabetes clinics in Abha City, Asir region, recruited between August 2023 and December 2023. Adult patients aged 18 and over with T2DM were included, and data was extracted from patient files. All patients were examined by ultrasound to determine the prevalence and coexistence of MASLD in patients with T2DM. Hepatic steatosis on B mode ultrasound is qualitatively classified on a four-point scale: normal (0), mild (1), moderate (2), and severe (3). Results Out of 168 patients, 68.4% were identified with MASLD, mostly with diffuse liver (97.4%) diagnosed through ultrasound. MASLD was significantly higher in individuals with uncontrolled diabetes (72.5%) than those with controlled diabetes (46.2%), with a significant difference (p=0.015) and an odds ratio (OR) of 3.081, indicating uncontrolled diabetics are over three times more likely to develop MASLD. The uncontrolled group had a statistically significant larger liver size than the control group (13.6cm ±1.43 vs. 13.0cm ±1.20, respectively: [p=0.032, 95%CI 0.053-1.12]). Furthermore, a notable association was observed between increased BMI and the prevalence of MASLD in individuals with T2DM. Furthermore, no significant association was found between the duration of diabetes and the severity of MASLD, nor between the grading of MASLD and gender. Conclusion This study highlights a crucial association between uncontrolled diabetes and increased MASLD prevalence, emphasizing the importance of diabetes management in reducing MASLD risk.

Coreless axial-flux permanent-magnet (AFPM) machines have recently gained prominence as efficient power generation solutions. Eliminating the core resolves challenges such as eddy current losses and cogging torque, enhancing overall efficiency. This topology enables high power density, further amplified in fully coreless configurations. Nevertheless, the proliferation of coreless AFPM machines faces hurdles as to high leakage flux and weaker structural integrity. Additionally, adopting multi-phase setups in AFPM introduces challenges, requiring additional winding coils and enlarging the stator diameter, leading to bulkier machine designs. This article underscores the significance of a lightweight, fully coreless six-phase machine and proposes a modular, multi-stage, multi-phase design tailored for fault-tolerant small-scale power generation applications. Furthermore, it explores the impact of employing double-layer winding coils on air-gap-flux density and power output. To realize this aim, a six-phase multi-stage AFPM generator was designed and simulated using ANSYS Maxwell®. Subsequently, a laboratory-scale prototype was fabricated accordingly. The simulation findings closely align with the experimental results obtained from the prototype, demonstrating the achievement of 1.3 kW power output. Notably, the six-phase machine with fully coreless concept exhibits a substantial power density of 205 W/kg. Multi-stage design boost efficiency and power density, presenting potential for small-scale applications.

The proliferation of Internet of Things (IoT) devices has brought about an increased threat of botnet attacks, necessitating robust security measures. In response to this evolving landscape, deep learning (DL)-based intrusion detection systems (IDS) have emerged as a promising approach for detecting and mitigating botnet activities in IoT environments. Therefore, this paper thoroughly reviews existing literature on botnet detection in the IoT using DL-based IDS. It consolidates and analyzes a wide range of research papers, highlighting key findings, methodologies, advancements, shortcomings, and challenges in the field. Additionally, we performed a qualitative comparison with existing surveys using author-defined metrics to underscore the uniqueness of this survey. We also discuss challenges, limitations, and future research directions, emphasizing the distinctive contributions of our review. Ultimately, this survey serves as a guideline for future researchers, contributing to the advancement of botnet detection methods in IoT environments and enhancing security against botnet threats.

The emergence of Industry 4.0 entails extensive reliance on industrial cyber-physical systems (ICPS). ICPS promises to revolutionize industries by fusing physical systems with computational functionality. However, this potential increase in ICPS makes them prone to cyber threats, necessitating effective intrusion detection systems (IDS) systems. Privacy provision, system complexity, and system scalability are major challenges in IDS research. We present FedSecureIDS, a novel lightweight federated deep intrusion detection system that combines CNNs, LSTMs, MLPs, and federated learning (FL) to overcome these challenges. FedSecureIDS solves major security issues, namely eavesdropping and man-in-the-middle attacks, by employing a simple protocol for symmetric session key exchange and mutual authentication. Our Experimental results demonstrate that the proposed method is effective with an accuracy of 98.68%, precision of 98.78%, recall of 98.64%, and an F1-score of 99.05% with different edge devices. The model is similarly performed in conventional centralized IDS models. We also carry out formal security evaluations to confirm the resistance of the proposed framework to known attacks and provisioning of high data privacy and security.

This study presents a novel approach to electrochemical detection of orthophosphate in potable water using hydrothermally synthesized nickel foam electrodes, modified with cobalt oxide (CoOx), zinc oxide (ZnOx), and zinc-cobalt oxide (ZnCoOx) nanocomposites. The incorporation of zinc-cobalt oxide into the electrode significantly enhances its stability and detection capability. In-situ phosphate detection was performed using voltammetric techniques in a highly alkaline environment (pH 14) facilitated by sodium hydroxide (NaOH). Comprehensive electrode characterization, including cyclic voltammetry (0 to 0.6 V at a scan rate of 50 mV s⁻¹), electrochemical impedance spectroscopy (10⁵ to 10–2 Hz), scanning electron microscopy, and energy-dispersive X-ray spectroscopy, confirmed the superior performance of the synthesized electrodes. Among the tested configurations, the zinc-cobalt oxide nanocomposite on nickel foam exhibited outstanding sensitivity, with a sensitivity of 0.4 μA/μM across a concentration range of 0 to 40 μM, and an elevated sensitivity of 4.26 μA/μM within the 50 to 100 μM range. The electrode achieved a remarkably low detection limit of 0.171 μM L⁻¹ (0 to 40 μM detection range) and 0.324 μM L⁻¹ (50 to 100 μM, detection range), underscoring its potential for highly accurate phosphate detection. These findings highlight the sensor’s applicability for diverse practical uses in water quality monitoring.