Libya Journal of Applied Sciences and Technology
The Libya Journal of Applied Sciences and Technology (LJAST) is a peer-reviewed, open-access scientific journal published by the College of Engineering Technology – Janzour, Libya. The journal is dedicated to publishing high-quality original research, review articles, and applied studies in the fields of engineering, applied sciences, technology, and interdisciplinary research. LJAST aims to provide an academic and professional platform for researchers, academics, engineers, industry professionals, and decision-makers to exchange knowledge, share innovative ideas, and present practical solutions to contemporary scientific and technological challenges. The journal particularly encourages applied and industry-oriented research that contributes to technological advancement, sustainable development, innovation, and the integration of scientific research with real-world applications at both regional and international levels. As an open-access journal, LJAST ensures that all published articles are freely accessible to researchers and readers worldwide, supporting the broad dissemination of scientific knowledge and promoting global academic collaboration. The journal follows a rigorous peer-review process and is committed to maintaining high standards of academic integrity, research quality, ethical publishing practices, and scientific excellence.
College of Engineering Technology – Janzour,
The Numerical Solution of Boundary Value Problems in Ordinary Differential Equations
This paper presents one of the numerical methods commonly used to find the approximate solution of boundary value problems with regular dimensions for second-order ordinary differential equations, known as the finite difference method. The numerical solution for such problems was found, results were tabulated and compared with the analytical solution. Graphical figures were also presented to support the numerical results. This method is considered one of the uncomplicated methods, and its results converge significantly with the exact solution.
Copyright (c) 2023 https://creativecommons.org/licenses/by-nc/4.0
Using Bernoulli's Differential Equation To Solve Thermodynamic And Aerodynamic Problems Describing Changes In Velocity Or Pressure
Bernoulli's equation represents a cornerstone in fluid dynamics, describing the interdependence of pressure, velocity, and elevation along a streamline. Rooted in the principle of energy conservation, it offers essential insights into the behavior of thermodynamic and aerodynamic systems. This study investigates the application of Bernoulli's differential form to analyze variations in velocity and pressure within fluid flows. The derivation, underlying assumptions, and practical implications of the equation are discussed in detail, with emphasis on its use in aerodynamic analyses (e.g., lift and drag estimation) and thermodynamic applications (e.g., flow behavior in nozzles and diffusers). Through selected case studies and computational simulations, the utility of Bernoulli's equation in engineering design and system analysis is demonstrated. Furthermore, the study addresses the equation's limitations, particularly in scenarios involving compressible and viscous flows, and outlines relevant extensions to enhance its applicability under such conditions.
Residue Upgrading Options for Maximum Gasoline Production From Libyan Crude Oil
Different refinery configurations are investigated for upgrading projects to increase gasoline production for local market demand. Libya is an important contributor to the global supply of light and sweet crude. It has five domestic refineries, all of which are simple hydro-skimming units. This work presents a theoretical approach for upgrading of atmospheric and vacuum residue derived from the heaviest Libyan crude oil. Obtained results show that option 3, which included delayed coking, has shown the optimum in terms of maximum gasoline.
Thermal Performance Assessment of Heat Exchangers In An Industrial Ethylene Production Facility
This study provides a comprehensive performance assessment of three critical heat exchanger units (2-H-301, 3-H-601, and 3-H-501) within an industrial Ethylene production facility in Ras Lanuf plant. Steady-state monitoring and direct data acquisition from operational equipment were conducted with subsequent data analysis performed using energy balance equations to quantify key thermal performance parameters. These parameters included overall heat transfer coefficients, heat duties, hot and cold fluid temperature and pressure ranges, capacity ratios, and effectiveness of each exchanger. Results reveal that the 2-H-2301 unit exhibits an overall heat transfer coefficient over 50% below the design specification and a heat duty exceeding 80% of the intended design. In the 3-H-901 unit, both heat duty and overall heat transfer coefficient were observed to fall over 75% below design standards, likely due to fouling, which adversely impacted effectiveness, capacity ratio, and the temperature profile of hot and cold streams. Conversely, performance of the 3-E-401 exchanger was within acceptable limits, with the heat duty, hot-side temperature differential, and capacity ratio aligning closely with design expectations. These findings offer a rigorous qualitative performance evaluation of the heat exchangers, highlighting areas requiring operational optimization to maintain design efficiency within industrial polyethylene processes.
Micro T- mixer: The effect of scaling factor and mixing angel
Different phenomena observed in various experiments indicate that the flowing mechanisms of liquids in microchannels are still not understood clearly. Computational fluid dynamics (CFD) simulation was used to simulate liquid flow in a T-shaped micromixer whose structural dimensions and operating conditions were varying. The results show that, the formation of vortices in the mixing zone arises through the influence of a T-junction (changes flow direction and gives rise to a secondary flow). After the mixing zone, the flow is almost fully developed and mixing occurs by a molecular diffusion mechanism only. The results also show that the mixing angle had a significant effect on the T-mixer performance. This can be attributed to the fact that for the engulfment flow regime, there is an optimum T-angle at which the effect of sharp bend reaches a strength value. If liquids enter into inlets with the same velocities, the flow was symmetrical; otherwise, the symmetry was broken up. The asymmetrical inlet velocities help to promote mixing quality. To illustrate the differences of liquids flow between macro- and micro-scale, the mixer is scaled in proportion, and the simulation shows that the smaller the mixer, the better the mixing quality.
Comparison of Petroleum Hydrocarbon Levels in Western Libyan Beach by Gravimetric and Spectroscopy Analysis
Fourteen shore water samples (denoted as w) from west of Tripoli shoreline, were examined for their petroleum hydrocarbon contents by gravimetric and spectroscopy analysis. Known amounts of beach water (w) were extracted with a suitable volume of chloroform (CHCl₃). The extracts were measured spectrophotometrically through calibration curves of absorptions at 410nm and 260nm to determine the concentration of petroleum hydrocarbons. Infrared analysis was also conducted on hydrocarbons extracted from shore water samples to assess the degree of oxidation occurred to the extracted hydrocarbons. This was obtained by comparing the relative absorption values at 1736 and 1712cm⁻¹ , normalized with respect to 2925 cm⁻¹; C-H stretching vibration; to rule out effects due to concentration. Gravimetrically, hydrocarbon concentrations in shore water (w) ranged from 0.05 to 9.50 ppm, while spectrophotometrically concentrations at 260nm and 410nm ranged from 0.470 to 2.74ppm, depending on location and industrial activities. The variation between the hydrocarbon concentrations by gravimetric method and the spectrophotometric method was due to the fact that gravimetric method measures total organics, but the spectrophotometric method focused on hydrocarbons which is a subset of organics. The Infra-red analysis showed densities at 1736cm⁻¹ (Acid-I) and 1712cm⁻¹ (Acid-II) which normalized with respect to the absorbance at 2925cm⁻¹ (Alkyl C-H) being equal to 1.00, the results were ranged 0.044 to 0.128 as acid-I and ranged 0.027 to 0.088 as acid-II, depending on effects of Prevailing Conditions.
Simulation and Performance Analysis of Photovoltaic Units under the Influence of Environmental Variables using MATLAB/Simulink
Solar energy is one of the most important renewable energy sources, effectively contributing to meeting the growing global demand for electricity while reducing carbon emissions. Despite the high performance of these units, a precise quantitative analysis of the impact of varying environmental factors on them using dynamic modeling remains essential to improve their performance in field conditions, particularly solar irradiance intensity and temperature, which directly affect the electrical conversion efficiency of the system. This study aims to model and simulate the electrical performance of a high-efficiency photovoltaic unit of type SunPower SPR-415E-WHT-D using the MATLAB/Simulink environment, in order to analyze the influence of environmental variations on current-voltage (I-V) and power-voltage (P-V) characteristics. The simulation was carried out over an irradiance range of 200–1000 W/m² and temperatures ranging from 15–35°C. The results showed that increasing irradiance leads to a significant rise in maximum power, increasing from 18.7 W at 200 W/m² to 424.8 W at 1000 W/m², representing a growth rate of approximately 2171%. In contrast, rising temperature causes a decrease in voltage and consequently power, with maximum power decreasing by 5.27% when the temperature increased from 15°C to 35°C. These results clearly highlight the urgent need for thermal management and the implementation of effective performance-enhancing strategies, including the integration of Maximum Power Point Tracking (MPPT) algorithms in photovoltaic systems, particularly in regions with hot climates and high solar irradiance levels.
Calculation of the Concentration Ratio and Solar Flux Distribution of the Truncated Pyramid Solar Concentrator Using Three-Dimensional Ray Tracing Simulation
The Truncated Pyramidal Solar Concentrator (TPSC) is a four-mirror device configured as a square frustum, utilized in solar oven technology for medium-temperature applications. This study aims to calculate the concentration ratio and solar flux distribution on the receiver by ray-tracing incident solar radiation from the aperture until it strikes the receiver or escapes. Assumptions include solar rays as equal, symmetric straight lines tilted by the altitude angle and the solar azimuth angle, and flat, smooth mirrors with negligible absorption. This study investigates the impact of mirror height, receiver-to-aperture area ratio, and solar ray incidence angles, on flux distribution and concentration. Results indicate that flux distribution is significantly affected by height, receiver-to-aperture area ratio. At (β=φ=0), the concentration ratio increases with both height and aperture area, although the latter only up to a limit. At (β=10) and (φ=0), the concentration ratio increases with height but decreases with increasing aperture area. Comparing the two cases, the concentration ratio is found to decrease with increasing altitude angle, suggesting that the TPSC is best utilized for a short period. The solar azimuth angle also reduces concentration, but less significantly than altitude angle. We conclude that height and aperture area have a major impact on flux distribution and concentration. This mathematical model is crucial as a design tool, providing a more accurate and detailed computational framework for flux mapping on the receiver compared to previous studies, thereby enabling thermal performance optimization in solar applications.
Machine Vision System for Industrial Engineering and Its Applications
This paper describes how to develop a machine vision (MV) system. The goal of machine vision system is to reduce human error and inspection time. The applications of MV will increase as a result of the decrease in price in MV equipment. In general there are three primary areas to apply MV which are measurement, inspection and guidance. MV measurement systems measure the two dimensions or three dimensions by enhancing and processing the digital image of the objects under investigation. Inspection systems compare the objects with a pre-stored images. Guidance systems instruct a machine to execute specific actions based on what it perceives. Today many production lines use automation to do repetitive tasks quickly and efficiently. Machine vision has been used statistical, mathematical, or trial and error methods to extract useful information from the captured images. Several mathematical and statistical methods has been used in MV such as Histogram Equalization, Probability and Statistics, Fourier Transforms, Differential Equations, Integration, Matrix and Algebra. The paper presents a concise overview of how to design a proper machine vision system and the tools that required to achieve this task. Also this paper shows some of the application of Machine vision system in Industrial Engineering.
STUDY EXACT SOLUTIONS AND ANALYTICAL OF LINEAR VIE’S USING NON-POLYNOMIAL SPLINE FUNCTIONS
في هذه الورقة البحثية تم تطبيق كل من دوال السبلاين غير متعددة الحدود الخطية والتربيعية لإيجاد الحل العددي لمعادلات فولتيرا التكاملية (VIEs). وقد تم اقتراح خوارزميات جديدة لأول مرة، وهو ما يُعد عنصرًا أساسيًا في هذا العمل. في القسم (2)، تم حل معادلات فولتيرا التكاملية الخطية من النوع الثاني باستخدام دوال السبلاين غير متعددة الحدود الخطية والتربيعية في القسمين الفرعيين (2.1) و(2.2) على التوالي. وفي القسم (3)، تم تقديم حل معادلات فولتيرا التكاملية الخطية من النوع الأول عندما تكون k(x, x) ≠ 0. أما في القسم (4)، فقد استُخدمت دوال السبلاين غير متعددة الحدود الخطية والتربيعية لحل معادلات فولتيرا التكاملية ذات النواة ضعيفة التفرد في القسمين الفرعيين (4.1) و(4.2) على التوالي. وفي القسم (5)، عُرضت أمثلة عددية للتوضيح والمقارنة بين الطريقة المقترحة ودالة السبلاين متعددة الحدود وطرق معروفة أخرى. وأخيرًا، تضمن القسم (6) مناقشة لنتائج الدراسة. تم تطوير خوارزمية لحل هذه المعادلات باستخدام برمجة MATLAB.
The Importance of Basic Elements in the Research Methodology Section of Scientific Writing
The content of "Materials and Methods" in the research paper provides the information through which the validity of the paper is judged. Therefore, the researcher is required to provide a clear and accurate description of how experiments or studies are conducted, and to rely on a logical basis to justify the choice of experimental procedures taken to answer the research question in a direct and organized scientific writing. Despite the abundance of scientific output in the Arabic language, it lacks the precision and quality in managing the content of the research methodology that precedes the results. The absence of basic scientific and logical narrative leads the reader to question the clarity of the method of reaching the results and perhaps the inability to benefit from the paper's content. Since there is a scarcity of focus on this topic in Arabic scientific research literature, and the research methodology is often presented as a simple and general part when discussing the writing of research papers, this paper will present a precise and specific scientific methodology in the Arabic language for writing the research methodology in scientific papers. Providing a clear and accurate description of how the study or research is conducted, especially quantitative research in applied sciences and engineering, supported by the logical scientific basis for conducting it, is one of the critical aspects of the quality of scientific writing.
Density Functional Theory for the Effect of Internal Energy and Dipole Moment on the Absorptivity of Heavy Elements Using Hydroxylated Iron(III) Oxide and Iron(II) Oxide Compounds
This study concluded that the hydroxylated iron(III) oxide compound Fe₃O₂(OH)₃ obtained more stable energy results than alone, and it was = -1962.811766411 Hartree, and in the case of merging with heavy elements, it was better stability than the state of iron(II) oxide Fe₂O₃, and this characteristic of these results in particular gives the preference in using it in the reaction and extracting heavy elements from an environment polluted with them. Also, the dipole moment results = 3.505542 Debye and ultraviolet absorptivity = 7289.97 nanometer, which is better than the state of iron(II) oxide compound Fe₂O₃ alone and combined with heavy elements in this study.
Comparison of PET Bottle Structure Performance Based on Finite Element Method (FEM)
In recent years, Polyethylene Terephthalate (PET) has become one of the most widely used polymers after polyethylene (PE) and polypropylene (PP) in several applications. The manufacture of water and juice bottles is one of the most important of these applications due to its physical properties such as transparency, hardness, and chemical properties, as it is considered chemically inert. In this research, two shapes, square and circular, were studied for a 7-liter bottle, which is used locally in bottling drinking water in abundance, by analysing its behaviour in the case of top loading through stress distribution and its effect on the bottle structure to ensure good performance with less usage weight of PET in order to have less impact on the environment. The structural performance of different bottle designs was studied using the Finite Element Method (FEM) with Abaqus software. The results has shown that, the bottle with a circular shape is better than the bottle with a square shape through its resistance to the upper load and the uniformity of the distribution of stresses on the bottle structure due to the similarity of the dimensions from the center of the bottle and the absence of a sudden difference in the dimensions of the design unlike the square shape.
Using Stable Isotopes of the Water Molecule (δ²H / δ¹⁸O) to Study Groundwater Recharge Methods and the Extent of Seawater Intrusion into Groundwater in the West Coast Region of Libya
This study has been conducted in the West Coast region / Libya, which is located about 45 km west of Tripoli city, which stretches from Sabratha west to Joudaim east, between longitudes of (12.425–13.025) and latitudes of (32.675–32.825). An isotopic study was carried out for 40 samples of groundwater (which were randomly selected) which distributed in four sections within the study area, in order to study the stable isotopes of the water molecule (δ¹⁸O), (δ²H), which gives evidence of groundwater charging methods and an indication of the influence of seawater intrusion into groundwater. This study suggests that the infiltration of non-evaporated rain water is the main origin of the groundwater in the study area. It also showed the presence of dissolution processes for some components of the reservoir rocks, which affected the increase in salinization of groundwater. Moreover, the obtained results reveal that the stable isotopes (δ¹⁸O), (δ²H) composition of groundwater samples showed that a few samples of groundwater have been affected by the interference of sea water, which are near the coast of the sea, while the rest of...
Al-Hadi Ahmed Abdallah Al-Shakl Al-Shakl
Study of Langmuir, Freundlich and Dubinin-Radushkevich Adsorption Isotherm Models for Lead and Copper Ions from Aqueous Solutions Using Moringa Seed Powder
Adsorption technology is considered one of the most important techniques used in treating water pollution problems, due to its high efficiency, simplicity of the technology used, and limited cost. This study addressed the adsorption of lead and copper elements in solutions using Moringa seed powder as an adsorbent material. The experiment was conducted in the laboratories of the Oil Research Center, where the adsorption of some heavy elements (lead and copper) from their aqueous solutions was tested. The adsorption process was subjected to adsorption equations (Langmuir - Freundlich and Dubinin-Radushkevich D-R), and all equations gave a good description of the interaction of the studied elements on the surfaces of Moringa seeds, in order to study the equilibrium process of these elements. It was found that the Langmuir and Freundlich models are more suitable in explaining the adsorption of these elements through the correlation coefficient R² values (which were 0.9991, 0.9971, 0.9844, and 0.8675) for the Langmuir and Freundlich models for lead and copper ions respectively, while they were 0.7807 and 0.674 in the Dubinin-Radushkevich model. The two elements under study also varied in their preference for adsorption surfaces, where the lead ion excelled in adsorption on the surfaces of Moringa seeds over the copper ion, which gave a lower adsorption percentage.
The Use of Internet of Things Applications in University Education from the Perspective of Faculty Members
With the tremendous development in the context of information technology and digital technologies in all fields, many educational institutions in developed countries have begun to realize the importance of Internet of Things technologies in their educational institutions. It has become necessary to keep pace with these developments and apply Internet of Things technologies, and to prepare university professors and students for these modern technologies. Despite the importance of using and the impact of the Internet of Things in the field of education, the Internet of Things will significantly change the way educational institutions and universities operate. The study aims to integrate and use Internet of Things technologies in the educational process in university education by knowing the degree of readiness of Libyan universities to integrate the Internet of Things into the educational process, and using new technologies for interaction between students and faculty members. According to Baqari [2], and to achieve the objectives of the study, the descriptive analytical method was used, through the application of a 42-item questionnaire to a sample consisting of 87 members of the teaching staff in Libyan universities, after verifying its validity by presenting it to a number of (3) arbitrators from the Faculty of Engineering at the University of Tripoli and the Faculty of Electronic Technology with experience and specialization in the field of information technology. The study included three main axes representing the requirements for using Internet of Things technologies, the importance of Internet of Things technologies, and the attitudes towards Internet of Things in the educational process. The results of the study showed that the sample individuals agreed to a low degree on the requirements for using Internet of Things technologies, the agreement of the sample individuals on the requirements of the importance of Internet of Things technologies came to a high degree, and the degree of agreement on the obstacles of Internet of Things came high, and it was also revealed that there were no statistically significant differences between the responses of the sample individuals to the requirements of using Internet of Things applications according to the opinions of faculty members in university education. The study recommended the necessity of developing the infrastructure and providing the necessary resources to employ Internet of Things applications in Libyan universities.
Computer Science, Artificial Intelligence & Data Science
Study the effect of surfactants on Emulsion Copolymerization rate of P-Methyl Styrene with Methyl Methacrylate
Two different types of surfactants one ionic surfactant and the non-ionic surfactant were used in this stage. The surfactants were dodecyl sulfate (SDS) and Sorbitan monooleate (Span 80) respectively. The kinetic study was carried out in PMMA seeded growth with the two different surfactants and it found that the conversion time of monomer into the polymer with span 80 was longer than the conversion time with SDS. Emulsion Copolymerization of P-Methyl Styrene with Methyl Methacrylate takes place in a two stage seeded emulsion polymerization. The synthesis of the polymer was done in the presence of surfactants. The initial stage involves the synthesis of PMMA particles through the use of emulsion polymerization reaction using dodecyl sulfate (SDS). The second stage involves the synthesis of PMMA–PPMS composite polymer particles. The PMMA particles will act as the seeds in the second
Copyright (c) 2022 https://creativecommons.org/licenses/by-nc/4.0
Effect of Phase Change Material on the Performance of a Packed Bed for Cool Latent Heat Storage Systems
This paper introduces a mathematical and numerical analysis of a packed bed containing spherical capsules filled with phase change material (PCM) for latent cool thermal energy storage (TES). The considered bed is the cylindrical tank and containing spherical capsules arranged in a random form. According to the energy balance on the PCM and the heat transfer fluid (HTF), the governing equations and boundary conditions are derived at transient conditions and used a continuous phase model in this model; the spherical capsules are assumed to behave as a continuous medium. The governing equations of the HTF and PCM are discretized using the implicit finite difference approach and central difference approximation. The resulting algebraic equations were solved used MATLAB program. The numerical results are obtained to study the effects of phase change material on the temperature distribution and energy stored in the bed in both charging and discharging modes.
Estimation and stability study of oleuropein from olive leaves extract (Olea europaea)
This study included extraction and estimation of oleuropein concentration in different types of olive leaves. It is the most important medicinal plants which is widely distributed in Libya and used in folklore medicine. The effect of different parameters (solvent, temperature, pH, extraction method and time) during and after extraction was studied. The obtained results showed that Chemlel and Corantina olive leaves have the highest oleuropein amount. In addition, the ideal conditions for extraction and maintaining the stability of the compound when using dioxane as a solvent were: 60% dioxane at 25°C and pH 3, and the soxhlet method is better than maceration.
Hydro-Power Energy Recovery in Water Pipelines Networks, A Case Study of Man-Made River in Libya
The Man-Made River (MMR) in Libya is one of the world’s largest water transfer systems, yet it consumes vast amounts of electricity to deliver water across long distances. This research addresses the challenge of energy demand by exploring the recovery of hydraulic energy that is normally wasted as pressure losses within the MMR pipelines. A hydraulic model of the pipeline was developed using EPANET, with actual design data serving as input. Four operational scenarios were evaluated (1.2, 1.3, 2.0, and 2.5 MCMD), and the results were analyzed to estimate recoverable energy and identify suitable turbine types. The methodology included simulation of head and pressure distributions, energy recovery calculations, and comparison with the system’s electricity consumption. The study found that at current operating flows (1.2–1.3 MCMD), turbines could recover between 686 and 733 MWh/day, meeting nearly half of the system’s electricity demand. At the original design capacity of 2.0 MCMD, recovery declined to about 610 MWh/day, while at 2.5 MCMD the net gain dropped to only 117 MWh/day due to pumping requirements. Francis turbines were identified as the most practical technology, with Pelton turbines as secondary options in high-head conditions. The research demonstrates that hydropower recovery from the MMR is technically feasible and environmentally beneficial. It could substantially reduce CO₂ emissions and strengthen Libya’s energy security by integrating renewable power directly into the national grid.
Copyright (c) 2026 https://creativecommons.org/licenses/by-nc/4.0
Study of cold storage design and the impact of basic variables on its effectiveness
In this paper, we study the different types of cooling and freezing stores that can actually be used to store and preserve foodstuffs, as well as the types of heat-insulating materials and moisture-insulating materials that are used in the structural composition of these stores, in addition to the method of calculating the various items that constitute the thermal load of these stores. For the purpose of evaluating and calculating the thermal loads of cold stores in big Market for storing table eggs and foodstuffs. In this research paper, the first and second warehouses were chosen for these stores. To complete these calculations, the design conditions (temperature) for the air outside the stores were determined based on the temperatures that were recorded for a period of 6 days from (11 am to 5 pm) and the temperatures that were taken from the meteorological station, the design conditions inside the warehouse were determined depending on the quality and grades of the stored food items Suitable storage temperature. Design calculations have been performed and practical readings have been recorded, and through the study it is clear that the capacity of the evaporators is much greater than the capacity of the stored materials.
Using ARIMA model to forecast the Reported Crimes in Libya from 2020 to 2025
A time series is a collection of data that was compiled chronologically. Most time series can be predicted based on their present and historical values. Software programs like SPSS and Minitab are made specifically to process time series data. The SPSS and Minitab software programs can be used to create the autoregressive integrated moving average (ARIMA) model, a time series forecast technique. In this paper, the forecasting process using the ARIMA model is illustrated using the SPSS and Minitab software. For instance, the predicted period for reported crimes (RC) in Libya is from 2020 to 2026.
Development of a Combined (Parallel & Parabolic) Rheomatic Device for Determination of Pressure Dependent Viscosity
Hydrodynamic pressure technique is a relatively new and innovative technique for rheological studies of viscous Newtonian fluids. These principles extensively used for the last twenty years for drawing and coating of strips and wires. The Rheometric Device consists of a rotating inner cylinder (rod) in a fixed hollow outer cylinder. The complex geometry gap between the two cylinders filled with a viscous non-Newtonian fluid. When the rod rotates inside, while the hollow cylinder filled with a viscous fluid, shearing takes place and hydrodynamic pressure develops, the magnitude of which is dependent on the shape of the surfaces, the viscosity of the fluid as well as the shear rate, the speed with which the inner solid rod is rotating. The Rheometer has been developed to determine the Rheological properties of fluid at pressures of up to 100 bar and a shear rate range of 500 to 400 sec⁻¹. Theoretical model developed based on Newtonian characteristics, shear rate viscosity relationship was determined using the Rheometer (combined parallel and parabolic unit) at different pressures by comparing the calculated theoretical pressure distribution with the experimental results
Evaluation of Gamma Ray-Induced Ultrasound Changes in Human Cells AFM and SEM Techniques at Low-Dose Exposure
Exposure to high-dose ionizing radiation is known as a human carcinogen factor, but our information about the effects of low-dose ionizing radiation such as occupational exposures is limited. The main concern of scientific community is biological consequences due to low-dose radiations. This study aims to evaluate the effects of low-dose gamma radiation on expression changes of apoptotic genes(bax and bcl-2) in the rat peripheral blood lymphocytes.In this experimental study, 42 adult male rats were classified into 6 groups, which was exposed to various doses values ranged from 20mGy to 1000mGy by y-rays from a Co-60 source. Blood samples were provided for analysis of gene expression 24 h after gamma radiation by relative quantitative Reverse Transcription - Polymerase Chain Reaction (RT- PCR). Radiation sensitivity of rat lymphocytes was measured by the bax/bcl-2 ratio as a predictive marker for radio-sensitivity.
Evaluation the Performance of Empirical Correlations for Predicting the Dead Oil Viscosity and Isothermal oil compressibility for Libyan Crude Samples
Understanding the PVT parameters is essential for various petroleum calculations, including the assessment of hydrocarbon flow characteristics, forecasting future performance, designing production facilities, and strategizing enhanced oil recovery methods. Ideally, the PVT properties of hydrocarbons are derived from laboratory analyses conducted on either bottom-hole samples or recombined surface samples. However, laboratory data may not always be accessible due to economic or technical constraints. In such instances, empirical correlations are employed to estimate these properties. These correlations have been formulated based on fluid samples from specific geographical regions. Given the diverse compositions of crude oils across different areas, relying on empirical correlations to predict PVT properties may yield unsatisfactory results when applied to hydrocarbons that behave differently from the fluid samples used to develop the correlations. This study assesses various PVT correlations to estimate the viscosity of dead oil (μod) for Libyan crude oils, utilizing 58 data points, and examines isothermal compressibility (Co) for Libyan crudes with 145 data points across approximately 100 distinct reservoirs. The evaluation criteria employed in this research include statistical and graphical error analysis. Existing correlations were applied to the Libyan dataset, and error analysis was conducted by comparing the predicted values with the original experimental values. The most accurate correlation for each PVT parameter has been identified. The findings indicate that the correlation proposed by Kartoatmodjo & Schmidt yields a dead oil viscosity with an Average Absolute Error Ratio (AAER) of 18.53% and a relative coefficient of R² = 0.1512. For isothermal oil compressibility, the correlation by Ahmed (1985) demonstrates the best performance, with an AAER of 31.67% and a relative coefficient of R² = 0.104%.
Lean Six Sigma, supply chain, analysis, Measure, DMAIC, control
The study sought to explore the impact of the approved approach of application of Lean and Six Sigma, which focuses on improving quality and reducing lead-time, and removing waste in the supply chain. As this integration of both applications is suitable for small and medium-sized companies (SMEs), the manager of company X wishes to solve its problems in lead time and transportation costs. The paper used the application of Lean and Six Sigma within the DMAIC stages.(define, measure, analyse, improve, control) The study also aims to take advantage of the stages through careful application of them to achieve the best results of reducing lead time and removing waste.
Resampling adjusted likelihood and average estimate approaches for microarray data analysis
The burgeoning field of genomics has reinvigorated interest in multiple-testing methods as it introduces new methodological and computational challenges. Whole genome microarray studies (e.g., differential expression, differential methylation, ChIP-chip) offer the possibility to test millions of traits in one genome. This article discusses the preterment of Adjusted likelihood approach and Average estimate approach (see Ewhida, Alammari and Ihwil, 2022; Jiang and Doerge, 2008) for estimating the proportion of true nulls π0 for CHIP-on-chip experiment data. Which has been done by Elnfati, Iles and Miller 2016, to express where the protein and DNA are bound, and the sample was taken from Drosophila fly (Fruit flies) in three replicates to determine the effect of HISTONE protein on fetus growth. The study demonstrates that, the Adjusted likelihood approach estimator performs very well.
Finite Element Analysis of Thermal and Residual Stress Fields in TIG-Welded Copper-to-Brass Dissimilar Joints
This study investigates a finite element analysis (FEA) of a dissimilar welded assembly consisting of a pure copper tube (C11000) and a brass flange, joined via the tungsten inert gas (TIG) welding process using ERCuSn-A filler metal. Numerical simulations were conducted using SolidWorks Simulation to evaluate the thermo-mechanical response of the joint under specific operating conditions. The research encompasses a transient thermal analysis of the welding process, followed by a static assessment of stress distribution and deformations induced by combined thermal and mechanical loading. The findings underscore the inherent challenges of joining dissimilar materials and demonstrate the critical influence of joint geometry on the assembly's structural integrity.
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Experimental Investigation of an Irrigation Water-Based Cooling System for Photovoltaic Water Pumping Applications in Desert Environments Part I: Thermal Performance Analysis
Photovoltaic (PV) water pumping systems have emerged as a reliable and environmentally sustainable solution for agricultural irrigation and water supply in remote regions. However, the performance of PV modules in arid and desert environments is significantly affected by elevated cell temperatures caused by intense solar radiation and high ambient temperatures. Although various cooling techniques have been proposed, many require additional energy consumption or impractical water use. This study proposes and experimentally investigates an innovative cooling approach in which a portion of the pumped irrigation water is diverted through a cooling circuit attached to the rear surface of the PV module and then reinjected into the irrigation stream. The proposed configuration provides effective thermal management without additional pumping energy or water losses. A theoretical model was developed to evaluate the influence of solar radiation and cell temperature on PV performance, and an experimental test rig was constructed and operated under desert climatic conditions in Biskra, Algeria. The results showed a significant reduction in PV cell temperature of up to 23°C under peak operating conditions. Consequently, the cooling process enhanced the electrical performance of the PV module, increasing power output by approximately 15–20% and improving conversion efficiency by about 1.7%. The proposed system represents a practical, low-cost, and water-conserving solution for improving photovoltaic water pumping performance in hot and water-scarce regions.
AI-Powered Time Series Forecasting for Sustainable Energy Management in Luxury Yachts
The luxury yacht industry is undergoing a transformative shift toward sustainability, with increasing emphasis on reducing carbon footprints and optimizing energy consumption in onboard systems, particularly in the hotel sector. This study presents a novel application of the Nonlinear Autoregressive (NAR) neural network for time series forecasting of energy usage and generation aboard luxury yachts. Leveraging real-world datasets from BlueAI, the study focuses on three critical energy streams: hotel electricity consumption, HVAC energy usage, and solar energy production. The NAR model, a feed-forward neural network with a sigmoid activation function in its hidden layer, was trained using historical time series data to predict short-term energy trends. By forecasting six hours into the future, the model enables dynamic energy management, allowing operators to preemptively adjust load demands, optimize HVAC settings, and maximize the use of renewable energy resources like solar panels. Performance evaluations in both training and real-time environments showed high predictive accuracy across all subsystems. This predictive capability is a crucial step toward greener yachting by enabling more intelligent energy scheduling, reducing dependence on fossil fuels, and minimizing greenhouse gas emissions. The integration of AI-driven forecasting tools like the NAR model promotes renewable energy adoption and contributes to global climate change mitigation efforts. The research highlights how smart technologies can align the luxury maritime industry with the goals of sustainability and environmental stewardship.