Wadi Alshatti University Journal of Pure and Applied Sciences
Wadi Alshatti University Journal of Pure and Applied Sciences (ISSN: 3006-0877) is a peer-reviewed, open-access academic journal dedicated to the dissemination of high-quality research in the fields of pure and applied sciences. Published biannually (two issues per year), the journal serves as a platform for researchers, scientists, and academics to share innovative findings and advancements in disciplines such as: Physical Sciences (Physics, Chemistry, Earth Sciences) Biological Sciences (Biology, Microbiology, Biochemistry) Mathematics & Statistics Environmental Sciences Computer Science & Information Technology Engineering & Technology (where applicable) Journal Mission The journal aims to promote scientific knowledge by publishing original research articles, reviews, and short communications that contribute to theoretical and practical developments in pure and applied sciences. It upholds rigorous peer-review standards to ensure the validity, significance, and originality of published work. Key Features Open Access: All articles are freely available to readers worldwide, ensuring broad dissemination of knowledge. Peer-Reviewed: Manuscripts undergo a double-blind review process by experts in the relevant fields. ISSN: Online ISSN 3006-0877 Frequency: Two issues per year (biannual). Indexing & Archiving: The journal is committed to being indexed in reputable databases to enhance visibility and impact. Article Processing Charge (Authors' Fees) This journal charges no authors' fees Article Submission Charge: 0.0 LD Article Processing Charge (APC): 0.0 LD WAUJPAS is run on a non-profit basis. Wadi Alshatti University covers 100% of the expenses of publishing Publisher The journal is published by Wadi Alshatti University, supporting the institution’s commitment to advancing scientific research and education in Libya and beyond. For inquiries, please contact the Editorial Office at [inf.wuj@wau.edu.ly].
This journal uses Creative Commons Attribution-Noncommerical 4.0 International License (CC BY-NC 4.0), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. To view a copy of this license, visit https://creativecommons.org/licenses/by-nc/4.0/. Copyright of articles Authors retain copyright of their articles published in this journal.
Design and Implementation of a Remotely Monitored Hybrid Renewable Energy System with IoT-Based Relay Control and Real-Time Data Logging
This paper presents a cost-effective smart hybrid renewable energy system (HRES) that integrates solar PV and wind energy systems and supports VRLA battery systems and DC loads. Stand-alone renewable energy systems are subject to intermittence. The design proposed in this paper addresses this issue by integrating both renewable energy systems using a four-channel relay board with an embedded electrical interlock that prevents simultaneous dual-source injection to a PWM charge controller and maintains solar energy priority. The control unit was an Arduino Mega 2560. It read the voltage and current of the PV, wind, and battery systems through the ACS712 Hall effect sensors and B25 voltage dividers, and established a solar-priority interlock. The interlock was improved by remote relay control through the MQTT protocol. The system logged data every 10 seconds in CSV format, displayed information on a 20 × 4 I²C LCD, and sent data wirelessly with the ESP8266 module to a MIT App Inventor mobile application via MQTT. Two test sessions were conducted. Session B (January 16, 2026) was an early validation test. Session C (March 13, 2026) was the main test and was conducted after the sensors were replaced and recalibrated. The combined-source load test (2.83 minutes) was conducted with a mean load power of 25.70 W and a single-sample peak of 26.79 ± 1.5 W (99.2 ± 5.6 % of the rated load). The maximum solar and wind powers were 34.36 W and 10.05 W, respectively. Following the implementation of necessary corrective measures, the relay and measurement consistency for both wind and output was 100%, confirming that the interlock and control logic performed as designed.
Copyright (c) 2026 Authors https://creativecommons.org/licenses/by-nc/4.0
Reservoir Characterization of Low-Permeability FACHA Formation in Hakim Field Using ECRIN Well Test Analysis
This study presents the Pressure Transient Analysis (PTA) of two wells in the Hakim field using pressure build-up test data. An Excel-based analysis model was developed to estimate the main reservoir parameters and was validated by comparison with results obtained from ECRIN (Saphir), the industry-standard software for pressure transient analysis. The comparison showed a close agreement between the Excel model and ECRIN results, demonstrating that the developed Excel model provides reliable estimates of reservoir properties. The studied wells, producing from the FACHA Formation, are characterized by low permeability, with permeability values ranging from 3.9 to 10.9 mD. The skin factor ranges from −3.38 to −0.60 for all wells except well A4, which exhibits a positive skin factor of 6.33 due to formation damage. The estimated average reservoir pressure in the Hakim field is approximately 2517 psi.
Dynamic versus Quasi-Steady-State Simulation of Shading Strategies for Cooling Load Reduction: A Case Study of an Educational Building in Tripoli, Libya
Buildings account for roughly 32% of global final energy consumption, and cooling represents the largest share of that demand in hot-arid climates, where educational buildings are particularly energy intensive due to long daily occupancy. This study evaluates five exterior shading configurations, a horizontal overhang, fixed horizontal louvers, louvers inclined at 15° and 30°, and an overhang combined with vertical fins, applied to the southern facade of a two-story, 1600 m² educational building at the University of Tripoli, Libya. The building was modeled in HAP, which applies a quasi-steady-state method, and in EnergyPlus (with SketchUp/OpenStudio), which applies a dynamic transient heat-balance method. A base case without shading was simulated in both tools before each shading system was applied in EnergyPlus. For the July design day, EnergyPlus predicted a peak cooling demand of 181.9 kW against 165 kW from HAP, 10.2% higher; for June, EnergyPlus predicted a total cooling consumption of 20,452 kWh against 38,268 kWh from HAP, 46.56% lower. For January, EnergyPlus predicted a peak heating load of 11.77 kW against 10.5 kW from HAP (12.1% higher) and a heating consumption of 10.56 kWh against 10,189 kWh from HAP (99.9% lower), reflecting HAP's tendency to average loads rather than resolve hourly transients. Among the shading systems, the 30° inclined louvers gave the largest annual cooling reduction (10.27%, from 136,886 to 122,833 kWh) and the largest peak demand reduction (1.51%), followed by 15° louvers (9.81%), horizontal louvers (9.10%), overhang with fins (7.46%), and the overhang alone (5.25%). Adopting this best performing system is estimated to avoid about 14.57 t CO2 per year, based on a national grid emission factor of 1.037 kg CO2/kWh. All five systems increased annual heating consumption relative to the 147 kWh base case, up to 542 kWh (269%) for the 30° louvers, since the geometry that blocks summer solar gain also blocks winter solar gain. Shading selection should balance cooling savings against this heating penalty, and dynamic simulation should be preferred over quasi-steady-state tools when peak and part-load performance matter.
Copyright (c) 2026 The authors https://creativecommons.org/licenses/by-nc/4.0
Wavelet-Enhanced DEMON Processing and Deep Learning for Passive SONAR Target Recognition
This paper presents an integrated underwater Automatic Target Recognition (ATR) framework that synergizes advanced signal processing with deep learning. To eliminate non-stationary ambient ocean noise and isolate low-frequency modulations, the raw acoustic pressure signals undergo pre-denoising via Discrete Wavelet Transform (DWT with db4 mother wavelet and soft-thresholding), followed by Detection of Envelope Modulation on Noise (DEMON) analysis to yield 128-bin spectral feature vectors. Classification is performed using a dedicated 7-layer 1D Convolutional Neural Network (1D-CNN) architecture terminating in a Softmax output layer. Acoustic simulations in MATLAB R2024b generated a balanced dataset of 1,200 audio samples (200 samples per class across six distinct targets: fast boat, rubber zodiac, human diver, giant turtle, dolphin, and mini submarine) propagated through a 20–40 path shallow-water multipath channel ( ). Experimental evaluations demonstrate an overall classification accuracy of 94.93% and a macro-averaged F1-score of 0.9505. Coupled with an average inference latency of 11.40 ms per target and Euclidean distance-based thresholding for out-of-distribution anomaly detection, the proposed system proves computationally efficient and well-suited for real-time passive underwater surveillance.
Antimicrobial Activity and Synergistic Effects of Libyan Extracts from Artemisia Herba-alba, Thymus Vulgaris, and Zingiber Officinale Against ATCC Strains of Bacillus Subtilis and Escherichia Coli
The increasing prevalence of antibiotic-resistant bacteria has intensified interest in medicinal plants as a promising source of natural antimicrobial agents. This study aimed to evaluate the antibacterial activity of ethanol, methanol, and aqueous extracts of Artemisia herba-alba, Thymus vulgaris, and Zingiber officinale against Bacillus subtilis and Escherichia coli. Antibacterial activity was assessed using the agar well diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and checkerboard assays to determine synergistic interactions with Streptomycin. In addition, phytochemical screening and high-performance liquid chromatography (HPLC) analyses were performed. The results demonstrated that Gram-positive bacteria were more susceptible to the plant extracts than Gram-negative bacteria. The ethanolic extract of A. herba-alba showed the strongest antibacterial activity, producing the largest inhibition zone (19.5 ± 0.6 mm) against B. subtilis and the lowest MIC (62.5 mg/mL). The strongest synergistic interaction with Streptomycin was observed for A. herba-alba (FICI = 0.41). HPLC analysis identified caffeic acid as the major phenolic compound (19.3 mg/g), together with other bioactive constituents, including thymol, carvacrol, and gingerol, which may contribute to the observed antibacterial activity. These findings highlight the potential of these plant extracts as natural antimicrobial agents and support further investigations into their pharmaceutical applications.
Copyright (c) 2026 The author https://creativecommons.org/licenses/by-nc/4.0
Bidirectional Cross-Dataset Generalization and Label-Efficient Adaptation for 5G Network Intrusion Detection
Machine-learning-based intrusion detection in 5G networks is often assessed using a single dataset, where strong test results may indicate regularities tied to that dataset rather than attack behavior that generalizes across settings. This study examines bidirectional cross-dataset generalization between 5G-NIDD and NetsLab-5GORAN-IDD through conservative semantic matching of denial-of-service, flooding, and scanning attacks. The assessment uses five-seed zero-shot transfer, a multivariate dataset-fingerprint audit, unsupervised correlation alignment, few-shot target adaptation, and class-blind target-label selection while varying attack prevalences in a controlled manner at 1%, 5%, and 10%. Zero-shot XGBoost performance was highly dependent on both the specific task and the direction of transfer. For matched aggregate tasks, balanced accuracy was 0.518 and 0.505 for application-layer denial-of-service, 0.807 and 0.500 for network/transport flooding, and 0.834 and 0.558 for scanning when transferring from 5G-NIDD to NetsLab and in the reverse direction, respectively. A dataset-source classifier reached balanced accuracy of 0.993 when using all 15 harmonized numerical features and maintained 0.993 after source-predictiveness-aware Top-6 filtering, indicating that dataset identity persisted across multivariate feature interactions. CORAL did not eliminate this fingerprint, whereas using limited target labels produced much larger improvements; in the exploratory adaptation experiment, the mean best gain with no more than 5% labeled target data was 0.346 balanced-accuracy points. Under deployment-like prevalence pressure, Random or Diversity-based querying provided the best overall strategy in 13 of 15 prevalence-budget conditions, while source-model uncertainty sampling was unstable. Overall, these findings indicate that realistic 5G intrusion detection depends on explicit cross-dataset evaluation and limited, target-specific supervision rather than on performance from a single dataset, feature filtering, or straightforward distribution alignment.
Seismic Geochemistry: A Sustainable Approach to Hydrocarbon Exploration in Libya
The growing need for sustainable resource management and environmentally responsible exploration has highlighted the importance of integrating emerging geoscientific approaches into national development strategies. Although Libya possesses significant hydrocarbon resources and diverse geological settings, the application of seismic geochemistry remains limited despite its considerable potential for supporting both energy exploration and environmental management. This study explores the role of seismic geochemistry as an innovative tool for sustainable development in Libya. The proposed framework emphasizes the integration of geochemical indicators with seismic surveys, geological information, well data, hydrogeochemical observations, and environmental monitoring to improve subsurface characterization and resource assessment. Particular attention is given to the identification of geochemical anomalies associated with tectonic activity, hydrocarbon migration, groundwater systems, and environmental hazards. The study demonstrates that integrating seismic geochemistry within multidisciplinary exploration workflows can improve hydrocarbon prospecting, reduce exploration uncertainty, enhance groundwater assessment, strengthen environmental impact evaluation, and support evidence-based resource management. Furthermore, the proposed approach contributes to minimizing environmental risks while improving exploration efficiency through advanced geochemical interpretation. The findings highlight the potential of seismic geochemistry as a strategic decision-support tool capable of promoting sustainable development in Libya by integrating scientific innovation, environmental protection, digital geological analysis, and responsible management of natural resources. The proposed framework further supports sustainable development in Libya's resource-rich regions by enhancing environmentally responsible hydrocarbon exploration, strengthening evidence-based resource governance, and promoting long-term economic and environmental sustainability.
Linear Detection in 28 GHz Massive MIMO Uplink Systems
Massive Multiple-Input Multiple-Output (Massive MIMO) systems represent a cornerstone for meeting the high-performance demands of 5G and beyond networks. This paper presents a comprehensive simulation framework that effectively couples electromagnetic physical characteristics with signal processing algorithms in the uplink transmission. A 16x16 planar antenna array comprising 256 elements was designed to operate at the 28 GHz millimeter-wave band, achieving a high array gain of 32.27 dB alongside precise beamforming capabilities. To evaluate system performance under realistic operating conditions, the spectral efficiency and Bit Error Rate (BER) of three prominent linear detectors—Maximum Ratio Combining (MRC), Zero Forcing (ZF), and Minimum Mean Square Error (MMSE)—were analyzed in the presence of noise and imperfect Channel State Information (CSI). MATLAB numerical simulations demonstrate that the MMSE detector provides the optimal trade-off between performance and computational complexity, achieving a BER of 10^ {-4} at an SNR of 15{dB}. Conversely, the ZF detector exhibited severe performance degradation due to noise enhancement under channel estimation error conditions (sigma_e^2 = 0.01). These findings offer practical insights for selecting scalable detector architectures in future wireless networks.
Structural Performance of Castellated Steel Beams with Flange-Connected Ring Stiffeners and Inverted Stiffener Geometry
This paper aims to study the behavior of castellated beams with large openings (D/H = 0.7) with a constant offset of 10 mm. Different configurations, including ring stiffeners connected to the flanges and geometrically inverted ring stiffeners, were investigated. Nonlinear finite element models in ABAQUS were used to compare circular and hexagonal openings. The hexagonal openings with flange-connected showed an increase in the ultimate load by up to 6.12% and improved the ductility factor from 5.65 to 6.33. Connecting the ring stiffeners of the circular openings to the flanges slightly reduced the ultimate load by up to 1.67%, while the ductility factor decreased from 4.25 to 3.39. The inverted geometrical cases led to lower performance, especially when the hexagonal openings were strengthened with a circular stiffener, with a decrease of 11.36%. Ring stiffeners connected to the flanges of castellated beams with large hexagonal openings can be used to control the web post buckling.
Robust Biomechanical Classification of Humans, Gorillas, and Robots under Urban Multipath Fading using Micro-Doppler Radar
This paper presents a physically grounded framework for classifying humans, gorillas, and robots using a 35 GHz Ka-band continuous-wave radar under realistic urban multipath conditions. Urban deployments face severe signal distortion due to multipath fading; Micro-Doppler radar is a pivotal tool for non-contact biomechanical classification. A total of twenty features are obtained from both biomechanics and spectroscopy and selected using Neighbourhood Component Analysis (NCA). Stacking ensemble learning that employs Random Forest, Support Vector Machine, K-Nearest Neighbours, and MLP, as well as linear support vector machine for meta-classifier is evaluated in five-fold stratified cross-validation using 400 original samples, augmented to 1200 using MATLAB (R2023b) . The system achieves a state-of-the-art accuracy of 90.92% ± 2.03% (95% CI: [89.14%, 92.69%]) with F1-score of 90.88% ± 2.08% under harsh urban conditions (SNR = 15 dB, K-factor=7 dB). The error analysis reveals that the use of multipath-aware augmentation and supervised feature selection leads to a significant reduction of the spectral smearing phenomenon, resulting in reduced errors for classifying human from robot at an impressive 68%. The gorilla is the class that shows the highest inter-class separability, with 95.0% accuracy. The robustness analysis demonstrates consistent behaviour across various signal-to-noise ratio and K-factor combinations due to the stacking ensemble technique that eliminates any distribution shift within the feature space. Ka- and radar detection enhances the frequency resolution of the Micro-Doppler features, improving the inter-class separability while accounting for high-order scattering phenomena. This work provides a comprehensive baseline for Micro-Doppler human-robot classification in an urban environment and it is noted that this study relies on simulation-based validation; thus, real-world Ka-band radar data is required for final empirical verification.
Urban multipath fading; Stacking ensemble
Geochemical Approaches to Combating Desertification and Enhancing Sustainable Development in Libya
One of Libya's biggest environmental problems is desertification, which is caused by the country's arid and semi-arid climate, low rainfall, high temperatures and evaporation, drought, groundwater depletion, soil salinization, wind erosion, vegetation degradation, and unsustainable land-use practices. The potential of geochemical methods for comprehending, tracking, and preventing desertification as well as promoting sustainable development in Libya is assessed in this study. In order to examine climatic and environmental changes from 2000 to 2025 and their implications for future desertification, the study combines geochemical examination of soil and groundwater with satellite remote sensing and spatial analysis. Temperature, rainfall, and vegetation-cover variations were investigated using MODIS Terra land surface temperature (LST), NASA GPM IMERG precipitation, and Landsat data. With average July LST rising from roughly 29.6°C in 2000 to 34.3°C in 2025 and yearly rainfall falling from 98.6 to 55.2 mm, the results show a significant warming trend. Additionally, there is a general decrease in vegetation cover, especially in inland agricultural areas, oasis systems, and portions of mountainous and coastal regions. By 2050, almost 80% of Libya's geographical area might undergo high to intense desertification, according to a business-as-usual forecast. For evaluating soil fertility, salinity, nutrient availability, pollutant movement, groundwater quality, water–rock interactions, and seawater intrusion, geochemical techniques offer useful instruments. As a foundation for sustainable land and water management, the study highlights the combination of geochemistry, remote sensing, GIS, sophisticated analytical technologies, isotopic techniques, and data science.
Study of Natural Marble Specifications in Southern Libya
This study evaluates the chemical, physical, and mechanical specifications of natural ornamental stones from five quarry sites in the Wadi Alshatti / Zella region of southern Libya: Tarouth, Mahruqa Right, Mahruqa Left, Zella, and Al-Ghaylaniya, all locally marketed as "marble." Samples were characterized by X-ray Fluorescence (XRF) chemical analysis, bulk density and water absorption (ASTM C97), uniaxial compressive strength (ASTM C170), and sulfuric-acid (H2SO4) resistance, with three replicate specimens per site. Results show that Mahruqa Left exhibits the highest compressive strength (87.45 ± 0.77 MPa) and CaO content (87.8%), with low water absorption (0.31%) and a density of 2.68 g/cm3, consistent with a high-purity calcitic marble. Tarouth (CaO = 79.7%; 64.93 MPa) and Mahruqa Right (CaO = 75.9%; 64.00 MPa, currently inactive) classify as dolomitic and calcite-dolomite marbles, respectively. Chemical analysis reveals that the Zella stone is not true marble: its exceptionally high sulfate content (SO3 = 31.91%) identifies it as a calcite-sulfate onyx of evaporitic/hydrothermal origin rather than a metamorphic carbonate rock. Similarly, Al-Ghaylaniya, with MgO = 19.60%, the highest water absorption (8.78%) and the lowest compressive strength (34.30 MPa), is geologically a dolomitic travertine. These findings indicate that two of the five commercially traded "marble" sources are mineralogically distinct stone types, with direct implications for correct classification, pricing, and end-use selection in the Libyan dimension-stone industry.
The Impact of Fuel Type on the Economic, Environmental, and Energy Performance of Power Generation Plants: A Case Study of the Ubari Gas Power Plant-Libya
This study aims to analyze the effect of fuel type on the thermal, environmental, and economic performance of power generation plants. The Brighton cycle model, with ideal gas and stable operation assumptions, was used to evaluate turbine performance using crude oil, natural gas, diesel, and heavy fuel oil. The results showed that natural gas achieved the highest thermal efficiency (up to 35.7%), the lowest CO2 emissions, and the lowest energy production cost compared to the other fuel types. Crude oil and heavy fuel oil, on the other hand, exhibited the lowest thermal performance, highest emissions, and highest energy production cost. The study also revealed that specific fuel consumption increases with decreasing thermal efficiency. These findings highlight the importance of fuel type selection in improving plant efficiency and reducing environmental impact, making natural gas the optimal choice for gas turbine operation.
Assessing the Effectiveness of Ondansetron and Dexamethasone in Reducing Nausea and Vomiting during Caesarean Section under Spinal Anaesthesia: A Systematic Descriptive Review
Background: Elective cesarean sections are commonly treated with spinal anesthesia, which is the most commonly used analgesic method. Nausea and vomiting following cesarean section with spinal anesthesia are frequently reported concerns of patients. The purpose of this study was to assess the effectiveness of medications in reducing nausea and vomiting in women who have undergone a cesarean section and spinal anesthesia. Methods: To conduct a systematic review, we searched the PubMed and Google Scholar databases for keywords such as nausea, vomiting, cesarean section, spinal anesthesia, ondansetron, and dexamethasone. The search for articles took place from 2014 to 2022. Results: Six studies were included, which consisted of five randomized controlled trials (RCTs) and one non-randomized clinical trial (NRCT). Similar drugs were used in these studies with different dosages to prevent nausea and vomiting following a cesarean section. The use of intravenous dexamethasone, intravenous ondansteron, and their combination was a part of the interventions. Conclusion: Dexamethasone's delayed effect on nausea and vomiting is not a concern, but given the findings, it could be a safe alternative to Ondansetron for postoperative nausea and vomiting prophylaxis. The preferred first-line agents seem to be Ondansetron, which is a 5-HT3 receptor antagonist. Using Ondansetron and dexamethasone together has been shown to help decrease nausea and vomiting during and after a cesarean delivery using spinal anesthesia.
Surra Infection in Imported Camels: The First Detection in Southern Libya
Camel trypanosomiasis is considered one of the most important veterinary health problems worldwide. A parasitological investigation was conducted for the diagnosis of trypanosomiasis using Giemsa-stained thin blood smears. A total of 130 blood samples were examined, of which 115 samples (88.4%) were negative, while 15 samples (11.5%) were positive for Trypanosoma spp. This study represents the first documented record of camel trypanosomiasis in southern Libya. An epidemiological survey was carried out in March 2023 to estimate the prevalence of Trypanosoma spp. infection among imported dromedary camels (Camelus dromedarius) in Sebha City, southern Libya. To date, no published studies have reported trypanosomosis in this region. The results showed a higher prevalence of infection in male camels (6.9%) compared with females (4.6%). In addition, the infection rate was greater among male and female camels older than 10 years than among younger age groups. Microscopic examination of thin blood smears confirmed the presence of Trypanosoma infections regardless of age or sex. The findings of the present study indicate that trypanosomiasis is common in the investigated area. Considering these results, the potential health risks and associated diseases affecting camels warrant further attention and implementation of appropriate control measures.
Feature-Selected Machine Learning for 5G Intrusion Detection: Leakage-Aware Evaluation and Sensitivity to Sequence Metadata in 5G-NIDD
Fifth-generation networks present a multifaceted and software-centric attack surface, thereby necessitating a systematic approach to reproducible intrusion-detection evaluation through traffic data gathered from authentic 5G environments. This investigation examines binary intrusion detection utilizing the comprehensive 5G-NIDD Combined.csv dataset acquired from its official IEEE DataPort distribution, adhering to a standardized leakage-aware methodology. The original dataset comprised 1,215,890 records and 52 columns. Following the elimination of 21 exact duplicate entries, 1,215,869 observations were retained. A stratified 70:30 partition was executed at the record level prior to preprocessing, with all data-dependent procedures being exclusively calibrated on the pertinent training dataset. The application of zero-variance filtering, Pearson-correlation reduction, and ANOVA F-test ranking condensed the 46 usable predictors into a consistent Top-10 representation. Random Forest, XGBoost, and a scalable random Fourier feature support-vector machine (RFF-SVM) approximation of an RBF-kernel classifier were assessed employing an untouched holdout partition in conjunction with five-fold stratified cross-validation, incorporating fold-specific preprocessing and feature selection. XGBoost and Random Forest attained Top-10 holdout accuracies of 99.9748% and 99.9745%, respectively, with no statistically significant disparity between their paired errors subsequent to Holm correction. The full, correlation-reduced, and Top-10 representations yielded virtually identical outcomes for both ensemble models, suggesting that the compact feature set maintained rather than enhanced random-split performance. Nevertheless, Seq and Offset emerged as the two highest-ranked predictors. The exclusion of these predictors resulted in a decline in holdout accuracy to 71.18% forXGBoost, 71.16% for Random Forest, and 73.09% for RFF-SVM, with a similar trend noted during cross-validation. These results illustrate that nearly flawless record-level outcomes are heavily contingent upon acquisition-order metadata and should not be construed as indicative of cross-session or cross-environment generalization. Prior to operational implementation, session-aware, base-station-aware, and external validation are imperative.
Association of Vitamin D Levels with Asthma Control among Pediatric Patients in Wadi Al-Shatti, Libya
Background: Asthma is the most common chronic inflammatory respiratory diseas in children. It has significant impact on morbidity and reduced quality of life worldwide. While recent research has highlighted the potential of vitamin D as an immunomodulator in asthma pathophysiology and control, the evidence remains controversial. Furthermore, data regarding this relationship in North African populations, particularly in Libya, are notably limited. Objective: This study aimed to investigate the relationship between vitamin D status and asthma control among asthmatic children and adolescents in Wadi Al-Shatti region, southern Libya. It further sought to assess serum 25-hydroxyvitamin D (25(OH)D) levels and their associated factors, as well as exploring the correlation of the targeted cases with immunological responses and key biochemical indicators. Methods: A total of 50 children aged 1–15 years were enrolled in this observational study. Participants were identified and recruited from Brack General Hospital and Qaqam General Hospital. Data collection was performed in two intervals: January–March 2023 and December 2023–March 2024. Asthma control was assessed according to the GINA guidelines and the Childhood Asthma Control Test (C-ACT). Laboratory investigations included serum 25-hydroxyvitamin D, total immunoglobulin E, calcium, phosphorus, alkaline phosphatase, and complete blood count. Statistical significance was defined as p < 0.05 using SPSS version 26. Results: Among the 50 participating children, the majority of participants were males (64%), compared to female (36%), of whom 80% presented with uncontrolled asthma. Vitamin D deficiency was highly prevalent, with the majority of targeted individuals exhibiting serum levels below 20 ng/ml. A significant correlation was found between vitamin D levels and asthma control, with lower levels more frequently identified in children with uncontrolled disease. Furthermore, significant associations were identified between vitamin D levels and serum IgE concentrations, as well as serum phosphorus levels. Additionally, red blood cell counts showed a significant association with vitamin D status, whereas calcium and alkaline phosphatase levels remained non-significant. Conclusion: Children with poor asthma control have a high incidence of vitamin D deficiency. These findings suggest that vitamin D status may represent an important modifiable factor influencing asthma outcomes in paediatric populations.
Study of Iron Deficiency Anemia Among Lactating Women in Mahrouka Ashatti Region- Southern Libya
Iron deficiency anemia in women is one of the most common nutritional problems, that is more prevalent in adolescents, pregnant and lactating (breastfeeding) women. To determine the prevalence of anemia, iron deficiency anemia and some of its causes in a group of lactating women who attending at health care centers in Mahrouka Al shatti region- southern Libya, EDTA blood samples were collected from 57 lactating women aged 19- 42 years in 15 Aug. to 20 Sep. 2018, for complete blood count and serum iron, Total Iron Binding Capacity for anemic women(Hb< 12gr/ dl). Thirty four lactating women (59.65%) were anemic, 26 (76.47%) had mild anemia, 7(20.59%) had moderate anemia and 1(2.94%) had severe anemia and 52.94%(18) were iron deficiency anemia. There were differences showed in hemoglobin values, with no correlations between Hb and women age, and between Hb and period of lactation. IDA and anemia were more prevalent in the lactating women and its relation to menstruation distributions, iron loss, breastfeeding and stress.
Comparison of Water Sorption and Solubility of CAD/CAM Milled PMMA, 3D-Printed PMMA, and 3D-Printed Resin Dental Polymers
The objective of this study was to evaluate and compare the water sorption and solubility of three dental restorative polymers—CAD/CAM milled PMMA, 3D-printed PMMA, and 3D-printed resin—after aging for different time intervals. For this purpose, thirty specimens (n = 10/group) were fabricated from CAD/CAM milled PMMA (PMMA DISC), 3D-printed PMMA (Temporary Crown), and 3D-printed resin (SDC Resin). Specimens were dried in a ventilated oven at 45 °C for 24 hours, and then immersed in purified water at 23 ±1°C. The masses were measured after 7, 14, and 30 days. Water sorption (Wsp) and solubility (Wsl) were calculated in µg/mm³. Assumptions of normality, variance homogeneity, and sphericity were tested. Sorption was analyzed via two-way repeated measures ANOVA with Games-Howell post-hoc; solubility, which violated normality, via Kruskal-Wallis with Dunn's post-hoc (α = 0.05). The achieved results showed that water sorption increased significantly with immersion time in all materials (p < 0.001). 3D-Resin demonstrated the highest sorption values, followed by 3D-PMMA, while Milled-PMMA exhibited the lowest values at all time intervals. At 30 days, mean sorption values were 16.77 ± 0.58 µg/mm³ (Milled-PMMA), 34.18 ± 3.68 µg/mm³ (3D-PMMA), and 47.68 ± 2.07 µg/mm³ (3D-Resin). Water solubility differed significantly among the tested materials (p < 0.001), with 3D-PMMA showing the highest solubility (5.39 ± 4.10 µg/mm³), followed by 3D-Resin (3.12 ± 1.63 µg/mm³), while Milled-PMMA exhibited negative values (−0.40 ± 0.26 µg/mm³). Consequently, it was concluded that material composition and immersion duration have a significant influence on water sorption and solubility of dental polymers. CAD/CAM milled PMMA exhibited higher hydrolytic stability, whereas 3D-printed resins demonstrated higher sorption and solubility, which makes them more susceptible to hydrolytic degradation. Clinically the materials selection for digitally fabricated restorations is critical, as the increased water sorption and solubility in 3D-printed resins may affect long-term clinical performance.
A Hybrid Steady-State Mathematical Model for a Brine-Recycle Multistage Flash Desalination System
A steady-state mathematical model for a brine-recycle multistage flash (MSF-BR) desalination system is developed for performance prediction and analysis. The proposed formulation combines the computational simplicity of section-wise steady-state models with selected rigorous thermodynamic features while avoiding the complexity of detailed stage-by stage formulations. The governing model consists of coupled mass, salt, and energy balance equations combined with heat-transfer relations for the recovery section, rejection section, brine heater, and mixing units. The resulting nonlinear algebraic equations are linearized using a modified tridiagonal model (TDM)-based approach and solved iteratively within a FORTRAN computational framework. The model is validated using published benchmark data for a 5 MGD brine-recycle MSF desalination plant reported by Rosso et al. Predicted temperatures, flow rates, salinities, heat-transfer coefficients, distillate production, and gain output ratio (GOR) show good agreement with the reference results, with deviations generally within acceptable engineering limits. The model also reproduces the effects of steam and seawater temperatures on plant performance. While deviations in distillate production and gain output ratio increase at elevated steam temperatures, the agreement remains satisfactory within the practical operating range of MSF desalination plants. The results demonstrate that the proposed model provides reliable steady-state predictions with moderate computational effort. Owing to its balance between physical realism and numerical simplicity, the model represents a practical tool for simulation, parametric analysis, and preliminary optimization of large-scale MSF desalination systems.
Does the Environmental Kuznets Curve Hypothesis Hold in Libya? An Extended Econometric Analysis of Economic Growth and CO₂ Emissions
This study examines the validity of the Environmental Kuznets Curve (EKC) hypothesis in the Libyan economy by analyzing the dynamic relationship between economic growth and CO₂ emissions over the period 1980–2024, within a broader sustainable development framework. The study employs both the Autoregressive Distributed Lag (ARDL) model and its nonlinear extension (Nonlinear ARDL - NARDL), allowing for the estimation of short-run and long-run relationships, as well as testing for cointegration using the Bounds Test. In addition, the model captures potential asymmetric effects of economic growth on environmental degradation. The results indicate the existence of a long-run equilibrium relationship among the variables, with evidence supporting the nonlinear form of the Environmental Kuznets Curve hypothesis. However, the estimated turning point exceeds the current income level, suggesting that Libya remains at a stage where economic growth is associated with increasing environmental degradation. Energy consumption is found to be the main driver of CO₂ emissions, while trade openness and urbanization are statistically insignificant. Moreover, no significant asymmetric effects are detected between positive and negative changes in economic growth. These findings highlight the importance of integrated economic and environmental policies aimed at improving energy efficiency and promoting a transition toward cleaner energy sources.
Design and Analysis of an off-Grid PV/Wind/Battery/Diesel Generator Hybrid Renewable Power System for a Healthcare Facility in Gharyan, Libya
This paper studies the efficiency of the proposed grid-tied hybrid renewable energy generation system at a large hospital in Gharyan, Libya. As mentioned earlier, the combination of the Eocycle EO20 wind turbine system with the proposed system involves a solar PV system of 50 kWp. Here, the batteries serve as the energy storage element, while the diesel engine serves as the backup energy source in the event of breakdowns. The energy generated from the sunlight is 94,091 kWh/yr, while that obtained from turbines equals 131,203 kWh/yr. Speaking of economic aspects, it can be stated that the proposed system is highly efficient, which is proved by its low LCOE 0.47$/kWh) and NPC (5,061$/year). Concerning the ecological aspects, the reduction in CO₂ emissions amounts to 83,393 kg/yr = 83.4 tons/year and Avoided Carbon Cost 478 $/year. More precisely, all these emissions come from buying electricity, since no diesel engines were used in the entire process.
Copyright (c) 2026 Ahmed Aisa, Sakhar Alharari, Ezzeddin Elarb, Yasser Nassar, Halla El-Khozondar https://creativecommons.org/licenses/by-nc/4.0
Effect of Heat on the Stability and Degradation of Vitamin C: A Thermodynamic and Kinetic Study
Vitamin C is an important antioxidant used extensively in pharmaceutical, food and cosmetic industries for its vital biological functions. But it is extremely prone to heat, light and oxygen–resulting in quick degradation and loss of efficacy throughout processing and storage. In this study, the thermal degradation, kinetic and thermodynamic stability analysis of vitamin C at different temperature in aqueous solutions were evaluated by UV–VIS spectrophotometry. The feasibility was investigated for vitamin C solutions at concentrations of 0.8% and 0.6% (w/v), with temperatures from 25 to 45 °C, over a time span of 5 to 25 minutes. The λmax was at 285 nm, with a decreasing absorbance as the temperature and exposure time increased indicated an increment of thermal degradation. The degradation process was characterized by first-order kinetic at all temperatures studied. According to results, the activation energy values were determined as 84.35 and 94.05 kJ mol⁻¹ for solutions of 0.8% and 0.6%, respectively, which highlighted a strong temperature effect on the degradation rate. Thermodynamic parameters showed positive values for enthalpy and entropy, suggesting that the degradation process is endothermic (ΔH > 0) and favors disorder in their molecular surroundings. Moreover, Gibbs free energy decreased with increasing temperature that the degradation process was increasingly spontaneous at higher temperatures. Overall, the findings offer useful practical insights towards optimizing storage conditions, improving thermal processing methods and possibly designing packaging systems to enhance stability and shelf life of products containing vitamin C for industrial purposes.
Copyright (c) 2026 Hajir Awadh, Nuri Abduali https://creativecommons.org/licenses/by-nc/4.0
Optimization Study of Converting the Derna Steam Power Plant to a Combined Gas/Steam Cycle
Research efforts have switched to increasing the efficiency of systems that convert thermal energy into mechanical labor due to the rise in the cost of oil and fuel gas over the past 20 years and the risks of environmental contamination.. Combined gas/steam power plants (CGSPP) are becoming more widespread due to their excellent thermal efficiency, higher capacity, and low environmental impact. The current research focuses on the theoretical analysis of CGSPP, which uses a single-pressure heat recovery boiler without supplemental fire. A computer program for the studied combined cycle based on the burning of 1 kmoles of natural gas in the combustor of the gas turbine is built utilizing the conservation equations for mass and energy, as well as combustion calculations. Each component of the combined cycle is assigned a unique subprogram using Engineering Equation Solver (EES). The results reveal that the combined cycle's maximum efficiency may be obtained at around 47.24 ⸓ as long as the boiler pressure remains constant. Since improved combined-cycle efficiency is the goal, modest compressor pressure ratios must be used. At a high compressor pressure ratio, the boiler pressure must be reduced to maintain a positive temperature differential at the pinch point. To minimize a loss in combined cycle efficiency at high compressor pressure ratios, we propose using a dual-pressure boiler.
The Effect of Adding Different Levels of Agricultural Sulfur and Fermented Sheep Residues on Readiness (N, P, K) in Soil and Their Concentration in Wheat Grains (Triticum aestivum L.) (Variety- Sham 6)
In the laboratories at Euphrates University- Faculty of Agriculture a pot experiment was conducted during the agricultural season (15/11/2023). The aim was to study the effect of varying levels of agricultural sulfur and fermented sheep manures on their readiness in soil and uptake (N, P, K) by field wheat plant (Triticum aestivum L.) (var-Sham 6) Agricultural sulfur (S95%) was applied at four levels (0,500, 1000 and 2000) kg S/ha and three levels of fermented. sheep manures bio-fertilizer (0, 10 and 20) tons/ha were applied: The highest readiness values of nitrogen, phosphorus, potassium and sulfur were achieved at the (2000) kg S/ha (S3) level of addition, the readiness of the element reached (14.79) mg/kg soil for nitrogen, (14.73) mg/kg soil for phosphorus, (273.14) mg/kg soil for potassium and (2273.01) mg/kg soil for sulfur.The amendment rate (20) tons/ha (M2) produced the highest available soil test values with (14.18) mg/kg soil N, (10.13) mg/g P and (271.50) mg/kg K and (1834.0) mg/kg sulfate in soil .Application of agricultural sulfur and fermented sheep waste at the highest levels resulted in a marked increase in nitrogen, phosphorus, potassium and sulfur concentrations in wheat grain seeds (variety- Sham 6), which were (2.810, 0.480, 0.275 and 0.393) % respectively. The interaction of the two factors (S3M2) produced the highest level of soil test availability (N-P-K-S), and the highest grain concentration of the same elements in wheat plants..The applying of treatment (S3M2) is of great importance in arid soil conditions in Syria and similar.
Phosphorus Dynamics and Their Relationship with Soil Properties in Soils of Tasawa Agricultural Project, Fazzan-Libya
This study evaluates the influence of soil physicochemical properties on the distribution and dynamics of total phosphorus (TP) and available phosphorus (AP) in cultivated and uncultivated soils of the Tasawa agricultural project. Soil samples were collected from five cultivated circuits and three reference sites and analyzed for pH, electrical conductivity (EC), organic matter (OM), cation exchange capacity (CEC), soil texture, TP, and AP using standardized laboratory methods. Both cultivated and uncultivated soils exhibited slightly alkaline pH values (7.72–7.86), which provided a basis for interpreting other soil characteristics. EC was elevated in cultivated soils (234.44–311.15 mS/m) compared to reference soils (213.22 mS/m), suggesting increased ionic content associated with agricultural activity. OM content was also higher in cultivated soils (1.97–2.54%) than in reference soils (1.90%). CEC values were marginally lower in cultivated soils (18.35–20.60 meq/100 g) relative to the reference (21.39 meq/100 g). The soils were predominantly sandy (>82%), resulting in low nutrient retention and influencing phosphorus distribution. TP concentrations were higher in cultivated soils (36.99–96.00 mg/kg) than in reference soils (29.54 mg/kg). AP levels remained consistently low (1.95–4.49 mg/kg) across all samples, indicating substantial phosphorus fixation. Multivariate statistical analysis revealed significant positive correlations between OM and TP, sand and AP, and pH and AP. Principal component analysis (PCA) accounted for 72.93% of the total variance, identifying four principal components: soil texture, organic matter, mineral composition, and ionic environment. Cluster analysis confirmed the strong association between OM and TP, and emphasized the roles of soil texture and pH in determining phosphorus availability. Analysis of variance (ANOVA) indicated significant differences (p < 0.05) among soil properties and phosphorus forms, whereas EC did not differ significantly. In summary, phosphorus behaviour in these soils is governed by the interactions among soil texture, pH, and organic matter. These results highlight the complexity of phosphorus dynamics in sandy arid soils.
Evaluation of the Inhibitory Activity of Aqueous and Alcoholic Extracts of Onion (Allium cepa L.) Scale Leaves Against Some Fungi Belonging to the Genera Aspergillus, Penicillium, and Mucor in Tripoli Markets, Libya
This study aimed to isolate and identify the fungal species responsible for the spoilage of onion bulbs (Allium cepa L.) and to evaluate the inhibitory potential of aqueous and alcoholic extracts of onion scale leaves as biological alternatives for fungal control. A total of 40 onion samples (20 red and 20 yellow) were collected from local markets in Tripoli, Libya, during the 2024-2025 period. Three scale leaf layers from each bulb were examined, and fungi were isolated on Potato Dextrose Agar (PDA).The results revealed significant fungal diversity and variation in the number of isolates between the two onion types; yellow onions recorded 72 isolates compared to 47 isolates for red onions. The identified genera included Aspergillus, Mucor, and Penicillium, with Aspergillus being the most dominant, exceeding a 60% frequency rate. Statistical analysis using the Mann-Whitney U test confirmed significant differences (P-value < 0.05) in fungal distribution, proving greater susceptibility in yellow onions. Inhibitory Activity, Antifungal efficacy tests at concentrations of 3, 5, and 7 mg/mL showed that the alcoholic extract of red onion was superior against Aspergillus spp., achieving a 92.47% inhibition rate. Meanwhile, the alcoholic extract of yellow onion recorded the highest inhibition against Penicillium spp. at 77.13%. Conclusion, the study confirms the higher efficiency of alcoholic extracts compared to aqueous ones in extracting active compounds such as phenols and anthocyanins. These findings suggest promising prospects for using these extracts in post-harvest crop protection to reduce economic losses and improve the quality and safety of onion crops in the Libyan local markets.
Association of Bottle-Feeding and Maternal Behaviors with Early Childhood Caries among Preschool Children in Brack Al-Shatti, Libya: A Cross-Sectional Study
Early Childhood Caries (ECC) is one of the most prevalent chronic diseases among children worldwide. Its development is strongly associated with early-life behavioral and feeding practices, particularly bottle-feeding habits and maternal behaviors, which play a critical role in the initiation and progression of dental caries. This study aimed to estimate the prevalence of (ECC) and examine its association with bottle-feeding practices and maternal behaviors among children in Brack Al-Shatti, Libya. A cross-sectional study was conducted between October and December 2025 involving 224 mother-child pairs. Data were collected using a structured, pre-tested questionnaire assessing Baseline Characteristics of the Study Populations, infant feeding practices, and oral hygiene behaviors. Early childhood caries was assessed through visual oral examination conducted by trained personnel. Associations were evaluated using Chi-square tests and multivariable logistic regression analysis, with statistical significance set at p < 0.05. The overall prevalence of ECC was 55.4%. Bivariate analysis revealed significant associations with adding sugar/honey to formula (p = 0.002), maternal pre-tasting (p = 0.002), nocturnal bottle-feeding (p = 0.004), and pacifier use (p = 0.020). Multivariable analysis identified adding sugar/honey to formula as the strongest independent risk factor (AOR = 3.63; 95% CI: 1.42–9.27; p = 0.007), followed by maternal pre-tasting (AOR = 2.05; p = 0.025) and nocturnal bottle-feeding (AOR = 2.05; p = 0.048). Protective factors included cleaning bottles before use (AOR = 0.41; p = 0.006) and cleaning the child's mouth after feeding (AOR = 0.34; p = 0.001). (ECC) is highly prevalent among children in Brack Al-Shatti and is significantly associated with modifiable maternal feeding behaviors. Preventive strategies should prioritize parental education on hygienic bottle-feeding practices, avoiding the addition of sugar to infant formula, and establishing early oral hygiene habits.
Evaluation of the Physical and Thermal Properties of Normal and Modified Black Raisins
The physical and thermal properties of black raisins within different moisture contents are important parameters during food processing. Some of the physical properties, namely moisture content, length, width, thickness, geometric mean diameter, sphericity, surface area, cross-sectional area, bulk density, true density, porosity, and the thermal properties, included thermal diffusivity, thermal conductivity, and specific heat, were determined at different percentages of total moisture (11.79% and 25.00% for black raisins). These physical and thermal properties are essential in determining the extent of compliance of raisin samples available in the Libyan market with the standard specifications for raisins. The results showed that there was a variation and significant differences in some physical properties of raisins when their moisture was modified. The results also showed a change in the values ​​of total and apparent density, porosity, and also the specific heat changed for black raisins were 3431.62 to 4070.72 j/kg.K) at different moisture levels. It is recommended studying the physical and thermal properties of raisin samples in different regions of the Libyan market.
Influence of Cathodic Polarization on Passive Film and Corrosion Behavior of 2205 Duplex Stainless Steel in 0.9% wt. NaCl
The influence of cathodic polarization on the electrochemical behavior of the passive film of stainless steels in physiological environments is significant. In such environments, hydrogen interactions and electrochemical modifications of this passive layer can directly affect the corrosion resistance and durability of these alloys. Although cathodic polarization has been widely studied regarding its effects on hydrogen embrittlement and stress corrosion cracking in 2205 Duplex Stainless Steel, the impact of such conditions on the electrical properties of the passive layer in physiological environments is inadequately researched. In this research the effects of cathodic polarization on the behavior of the passive film of 2205 duplex stainless steel in a 0.9% wt. NaCl solution were investigated. Electrochemical Impedance Spectroscopy and Mott-Schottky analysis were used to study passive film stability, semiconductor properties, and corrosion resistance. Results revealed that cathodic polarization introduced hydrogen into the passive film, decreasing the flat band potential to –0.08 V vs. Ag/AgCl, as well as increasing the donor density to 3.6x1020 cm-3. Electrochemical impedance spectroscopy suggested that the charge transfer resistance decreased, which is in good agreement with the passivity decay suggested by Mott-Schottky analysis. However, film thickness (1.9 nm) did not change, suggesting an electronic rather than structural changes in the passive film due to cathodic polarization. These findings highlighted the importance of understanding the trade-off between corrosion mitigation and hydrogen-induced film damage that might result from improper cathodic polarization practices.