Structural Properties of Graphs Defined by Bilinear Congruence on the Ring of Integers Modulo n
Journal ArticleWe investigate the structural properties of a graph defined on the ring. The Adjacency between two different vertices and is determined by the bilinear congruence. We analyze three fundamental cases, and for distinct odd primes. We describe the graph's breakdown into unit and non-unit vertex subsets. The unit subgraph forms disjoint cliques, with sizes depending on Euler's totient function. In contrast, the zero-divisor subgraph shows more complex behaviour governed by annihilation ideals. We establish general properties, including degree formulas, determination of maximum clique sizes in each component, determining the diameter, computing the girth, locating the graph centers, and finding the measures of vertex and edge connectivity. Additionally, we characterize independent sets and prove the existence of Hamiltonian cycles and supereulerian properties under certain connectivity conditions. Our results show how the prime factorization of influences these properties.
Hamza A. Daoub, (09-2025), ليبيا: مجلة جامعة الزاوية, 2 (2), 56-70
The Diophantine Exponent of Algebraic Numbers for β-Expansions with a Negative Base
Journal ArticleThe aim of this paper is to prove that the Diophantine exponent 𝐷𝑖𝑜( 𝑑−𝜷(𝑙𝛽)) is bounded by 𝑙𝑜𝑔𝑀(𝛽)𝑙𝑜𝑔𝛽+(𝑑−1)𝑙𝑜𝑔|𝑎𝑑|+1𝑙𝑜𝑔𝛽, where 𝛽 is an algebraic number, and 𝑀(𝛽) is the Mahler measure of 𝛽. In addition, a new result will be founded about transcendental number 𝑎 when 𝐷𝑖𝑜(𝑎) is infinite.
Osama AB M Shafah, (09-2025), الهند: IJLTEMAS, 9 (14), 66-71
The Effect of Temperature on the Optical and Electrical Properties of ZnO Thin Films
Journal ArticleZnO thin films were deposited on stainless steel substrates using the immersion method by immersing the
substrates in a sol-gel coating solution at temperatures of 70 °C and 80 °C for varying durations of (1, 2, 3, and 4minutes).
The results indicated that increasing the immersion time significantly influenced the film thickness. Optical measurements
showed that transmittance at a wavelength of 350nm increased with higher deposition temperatures. Additionally, the
Urbach tail energy increased with temperature, whereas the band gap (Eg) decreased markedly. Furthermore, the
electrical conductivity of the ZnO films improved with increased temperature and immersion time.
Aboalqasim Alqat, (08-2025), Libyan Academy: Academic Journal of Science and Technology, 6 (1), 277-282
Characterizing Human Body Shadowing at 32.5 GHz Through Cylindrical Diffraction Theory
Journal ArticleThe advent of 5G networks has revolutionized wireless communications by unlocking unprecedented data rates through millimeter-wave (mmWave) frequencies. However, the short wavelengths of mmWave signals (e.g., 32.5 GHz) make them highly vulnerable to obstructions, particularly human blockage, posing significant challenges for reliable link prediction and network planning. Existing models often oversimplify human-induced attenuation, limiting their accuracy in real-world scenarios. This work addresses this gap by proposing a cylindrical diffraction model to quantify human blockage effects at 32.5 GHz—the first application of such a model at this frequency. Through controlled experiments, we measured signal degradation as a human subject progressively blocked a 2-meter mmWave link, revealing a sharp decline in received power from −41.2 dBm (no blockage) to −69.7 dBm (full blockage). The cylindrical model demonstrated strong alignment with empirical trends, accurately capturing the nonlinear increase in attenuation as the human approached the line-of sight path. Notably, the model matched baseline measurements within 1.4 dB and predicted full-blockage loss within 7 dB of observed values, despite inherent simplifications. This study underscores the efficacy of cylindrical modelling for mmWave blockage prediction while highlighting critical refinements needed for practical deployment, such as incorporating material properties and antenna radiation patterns. By bridging theoretical and empirical insights, our work provides a foundational framework for enhancing 5G/6G network resilience in human-dense environments, ensuring robust performance for high-data-rate applications.
Ahmed Hassen ELjeealy Ben Alabish, (08-2025), Academy journal for Basic and Applied Sciences (AJBAS): الأكاديمية الليبية, 2 (7), 1-5
An Enhancement of Log Normal Shadowing Model to Estimate 5G Propagation Path Loss for the Indoor Environment
Journal ArticleThis paper presents a comprehensive study of modelling human body blockage (the most critical challenges in fifth-generation (5G)) effects on indoor millimetre wave (mmWave) communication links at 32.5 GHz, a key frequency for 5G networks. Through controlled experiments in a laboratory environment, we analyse signal attenuation as a human subject obstructs the line-of-sight (LOS) path between transmitter and receiver, recording received power at incremental positions. To model the observed phenomena, we propose a hybrid framework integrating deterministic and statistical components: (1) a modified Double Knife-Edge Diffraction (DKED) model with Gaussian-shaped blockage attenuation (20.8 dB peak at full blockage) and reflection-induced signal enhancement (−15.0 dB peak from nearby objects), and (2) a log-normal shadowing component (σ = 11.8 dB) capturing environmental randomness. Our results reveal strong agreement between simulations and measurements, achieving a mean absolute error of 3.2 dB and a correlation coefficient R² = 0.89. The analysis demonstrates that human-induced diffraction dominates near the LOS centre, while multipath reflections significantly alter signal strength at peripheral positions. We further derive practical guidelines for 5G network design, recommending a 44.4 dB link budget safety margin to account for combined blockage and shadowing effects. This work advances indoor mmWaves channel modelling by unifying physics-based diffraction analysis with empirical reflection characterization, the framework achieves strong experimental validation and offers actionable insights for 5G network design
Ahmed Hassen ELjeealy Ben Alabish, (08-2025), International Science and Technology Journal: المجلة الدولية للعلوم والتقنية, 37 (1), 1-13
دراسة تأثير درجات الحرارة على الخصائص التركيبية لأغشية أوكسيد الزنك ))
مقال في مجلة علميةتعتبر تقنية الاغشية الرقيقة لأوكسيد الزنك من التقنيات الرائدة في العديد من الصناعات المتقدمة، وذلك ما تظهره من كفاءة
عالية في صناعة الاجهزة الكهربائية والالكترونية، وتتميز خصائصها الفيزيائية بفاعلية عالية. ودراسة تأثير درجات الحرارة
على التركيب البلوري للأغشية الرقيقة يعتمد على تقنية التحضير، في هذه الدراسة قد اعتمدت طريقة الترسيب باستخدام
الغمر. واظهر الكشف بالأشعة السينية بأن غشاء أوكسيد الزنك النقي ذي التركيب السداسي المتراص، وعند قياس الحجم
البلوري لأغشية اوكسيد الزنك وجد انه يساوي قيم مختلفة للأطياف بسبب المعالجة الحرارية عند ℃ 80وذلك بسبب ظهور
شبكة على سطح الغشاء، وهذا النوع من التشكيل للأغشية يعطي جودة عالية. واظهر الكشف بالمجهر الالكتروني الى ظهور
عيوب في مادة الاغشية، التي لها تأثير على الخصائص الفيزيائية والكيميائية على الاغشية المرسبة. وأظهرت القياسات ان
متوسط سمك الاغشية المرسبة كان ما بين 14.26) μmو ،(18.68عند درجاتي حرارة ( ℃ .) 80℃, 70وكانت النتائج
في اتفاق جيد مع النتائج المنشورة.
فاضل عزالدين رحومة الشريف، ابولقاسم مسعود محمد القط، (07-2025)، Libyan Academy: Libyan Journal of Medical and Applied Sciences LJMAS، 3 (3)، 39-47
Chemical Analysis and Immersion Testing of a Hydrocarbon Film (Benzene) After Deposition on Glass Slides Using Plasma-Enhanced Chemical Vapor Deposition (PECVD)
Journal ArticleThin films deposited on glass surfaces can be produced by various
methods, including physical methods (thermal evaporation in
vacuum, sputtering, etc.) and chemical methods (chemical
deposition, chemical vapor deposition, thermal chemical analysis,
etc.). In this paper, thin films were deposited on glass slides using
the plasma-enhanced chemical vapor deposition (PECVD)
technique at pressures (10,30 and 50 mTorr) for varying durations
of (5,10 and 15 minutes). In addition, the results indicates that
increasing the deposition time significantly influenced the film
thickness while the adhesion does not directly depend on time.
Mohsan Salah Amara Eldakli, (07-2025), International Science and Technology Journal: مركز العلوم والتقنية للدراسات, 37 (1), 1-13
Effect of Nano-Refractory Bricks on the Morphological and Thermal Properties of PVC/LDPE Polymer Blend
Journal ArticleIn this study, the morphological and thermal properties of a blend consisting of 75% polyvinyl chloride (PVC) and
25% low-density polyethylene (LDPE), reinforced with nano-refractory bricks (NRB) at varying ratios (1%, 3%, 5%, and 7%),
were prepared and investigated. The objective was to enhance the blend’s thermal stability and surface structure homogeneity.
The morphological structure of the prepared samples was analyzed using scanning electron microscopy (SEM) and X-ray
diffraction (XRD). The obtained images revealed that the nano-refractory brick particles remained predominantly within the
PVC phase, resulting in an increased composite density without significantly affecting the LDPE phase. This suggests that the
overall morphology of the composite is largely unaffected by the presence of the nano-refractory bricks. From a thermal
perspective, thermogravimetric analysis (TGA/DTG) was conducted on all samples from room temperature up to 600 °C at a
heating rate of 10 °C/min. FTIR and TGA results indicated that the decomposition onset temperature shifted to higher values
due to the presence of nano-refractory bricks, with the most pronounced shift observed in the sample containing 3%
reinforcement. Additionally, the rate of mass loss was reduced. These findings demonstrate that reinforcing the PVC/LDPE
blend with nano-refractory bricks improves its performance, making it more suitable for applications that demand enhanced
thermal and mechanical properties, such as those in the construction and electronics industries.
Aboalqasim Alqat, (06-2025), Libyan Academy: International Journal of Innovative Science and Research Technology, 10 (6), 620-626
Assessment of microbial contamination levels on children's playground surfaces in AL-Zawiya and Jdayem Parks using the ATP Hygiene Monitor (PCE-ATP 1)
Journal ArticleThis study aimed to assess surface contamination levels of children’s playground equipment in two public parks in AL-Zawiya City, Libya (Jdayem Park and AL-Zawiya Park), using adenosine triphosphate (ATP) bioluminescence monitoring. The equipment surveyed included plastic slides, metal slides, iron swings, plastic swings, and rope swings. A total of 24 samples were collected from these surfaces using standardized ATP swabs, and results were classified based on established RLU thresholds (<100 RLU: clean, 100–300 RLU: marginally contaminated, >300 RLU: contaminated). The results revealed significant variability across equipment and surface types. The highest contamination level was observed on the iron swing at Jdayem Park (21–416 RLU), while the lowest levels were recorded on rope swings in AL-Zawiya Park (11–25 RLU). Plastic surfaces and rope swings generally exhibited lower contamination compared to metal surfaces, suggesting that surface material and design, combined with usage frequency, play a pivotal role in contamination accumulation. These findings align with previous studies that highlight the role of surface characteristics and environmental exposure in influencing microbial load. The results underscore the urgent need for targeted cleaning, disinfection, and regular quality
.monitoring of public playground equipment to maintain a safe, hygienic, and child-friendly recreational environment
Fathi Alhashmi Bashir Ali, (06-2025), Libyan Journal of Medical and Applied Sciences LJMAS: Higher Institute of Medical Sciences and Technology, Bani Waleed, 3 (2), 110-114
Evaluating the Accuracy of DKED and Fresnel Diffraction Models for Human Body Blockage in Indoor 5G Band Communications
Conference paperThis paper investigates human-induced signal attenuation in indoor mm-wave communications at 32.5 GHz, a critical concern for 5G systems. Two distinct diffraction-based models are applied to the same indoor scenario to assess human blockage effects: one employs the Double Knife-Edge Diffraction (DKED) approach, and the other uses Fresnel diffraction principles with complex Fresnel integrals. Controlled experiments with a human subject moving between a transmitter (TX) and a receiver (RX) reveal that the DKED model consistently underestimates the received power by 2 6 dB, while the Fresnel diffraction approach underestimates it by 2–5 dB Based on the comparative results, the DKED model demonstrates higher accuracy in predicting signal attenuation, offering valuable insights for improving indoor 5G network performance
Ahmed Hassen ELjeealy Ben Alabish, (05-2025), Academy journal for Basic and Applied Sciences (AJBAS): Academy journal for Basic and Applied Sciences (AJBAS), 70-75