International Journal of Engineering Research
The International Journal of Engineering Research is a new journal that provides solutions of faculty members to publish their research through a scientific platform concerned with scientific research and issuing their research in modern ways. https://doi.org/10.37375/issn.2958-6569
Faculty Of Engineering, Sirte University
Enabling 5G and IoT Through Small Cell Networks
Small cells are essential for advancing 5G and IoT networks by providing enhanced coverage, capacity, and energy efficiency in ultra-dense urban areas. This paper explores their role in integrating 5G technologies like massive MIMO, mmWave communication, and dynamic spectrum access. It focuses on interference mitigation, network densification, and optimizing wireless backhaul. Additionally, small cells support IoT deployments by integrating with low-power wide-area networks (LPWANs), enabling scalable and energy-efficient connectivity for massive machine-type communications. The study includes a comparative analysis of propagation models and deployment scenarios in urban settings, validated by MATLAB simulations. Results demonstrate the effectiveness of small cells in improving spectral efficiency, reducing latency, and ensuring reliable communication, highlighting their crucial role in realizing the full potential of 5G and IoT networks
Copyright (c) 2025 International Journal of Engineering Research
Risk assessment associated with Oil Storage Tanks. A case study: Buncefield accident
The rapid expansion of the global economy has led to an increased focus on energy reserve strategies and production necessities within the petrochemical industry. As a result, the scale of petrochemical storage tank farms has expanded significantly, leading to increased capacity and more intensive development efforts. In recent years, several severe incidents—such as oil spills, explosions, and fires linked to storage tanks—have underscored the urgent need for a comprehensive investigation into the combustion and explosion dynamics of these facilities. This paper examines the mechanisms of explosive combustion in environments involving crude oil tanks, offering an extensive review of both domestic and international research advancements in the areas of crude oil explosions and combustion. Furthermore, it discusses several widely recognized risk assessment methodologies relevant to managing storage tank risks. Both qualitative and quantitative evaluations, complemented by simulations of accident consequences, can provide vital technical support for safety management and emergency response initiatives. To mitigate the risk of future incidents, it is crucial to draw lessons from previous accidents, enhance theoretical research, and implement effective safety protocols. This strategy will not only improve the safety of national energy reserves but also promote the overall integrity of the petrochemical industry
Effect of Process Parameters on Metal Cutting Using Abrasive Water Jet Machining (AWJM) Technology: A Review
Abrasive water jet machining (AWJM) is a nonconventional eco-friendly machining method widely employed in many modern industrial applications. Among various process factors that influence the quality of machined surface cut using AWJM technology, water jet pressure, traverse speed, abrasive mass flow rate, stand-off distance, type of abrasive material, particle size, and work material are considered the key operating parameters. This paper reviews the findings of recent studies of the cutting of different workpiece materials using AWJM technology with regard to the impact of key process parameters on the machining responses such as surface roughness (Ra), kerf geometrical and dimensional accuracy, depth of cut, and material elimination rate (MRR), and makes recommendations for future research
Parametric Investigation on the Response of High-Density Polyethylene Pipes to Eccentric Loading
The durability of water distribution net- works partly relies on the ability of utility pipes to resist surface loading. In this paper, a parametric study is undertaken to investigate the response of high-density polyethylene (HDPE) pipes to eccentric loading. The results taken from a centrifuge model are used to evaluate the ability of a computational model to predict the bending moment distribution along the pipe. Following this validation process, the behaviour of HDPE pipes at a range of burial depths, and loading eccentricities is investigated further using the computational model. The results of this analysis are used to evaluate the High- way Agency guidelines for HDPE pipe burial depths, and they are found to be satisfactory, as they prevent exposure to the significantly higher bending moments experienced at shallow depths.
The Soil Reinforcement to Support Building Foundations
Soil reinforcement is a crucial technique in geotechnical engineering to improve the strength, stability, and load-bearing capacity of soil for supporting building foundations. Weak or loose soil can lead to structural failures, differential settlements, and long-term instability, necessitating the use of various reinforcement methods such as geotextiles, geogrids, soil nailing, and deep soil mixing. This research explores the effectiveness of different soil reinforcement techniques in enhancing foundation performance, analyzing their impact on soil strength, settlement reduction, and overall structural integrity. Through field studies and laboratory testing, the study evaluates the suitability of reinforcement methods for different soil types and load conditions. The findings provide valuable insights into cost-effective and sustainable soil stabilization techniques, offering practical recommendations for engineers and builders to optimize foundation design and construction. This research contributes to the development of resilient and durable building foundations, minimizing risks associated with poor soil conditions and ensuring long-term structural safety
The Optimizing Chemical Reactor Performance Using Frustum Geometry: A Comparative Analysis of Gas and Liquid Phase Reactions
This study investigates the impact of reactor geometry on chemical reaction efficiency, focusing on the application of frustum-shaped reactors compared to conventional cylindrical designs. The research examines the performance of gas-phase and liquid-phase reactions, evaluating conversion rates, pressure distribution, and overall reaction effectiveness. The results indicate that while frustum geometry enhances conversion in gas-phase reactions due to its unique pressure distribution, its impact on liquid-phase reactions remains minimal. These findings provide valuable insights for optimizing industrial reactor design and improving process efficiency
The Improving Throughput in Mobile Ad-hoc Networks MANETs Based on Spatial-based Multiple-Inputs Multiple-Outputs MIMO Solution using Simulation Approach
In wireless wide area networks (WWANs), Even though many access points (APs) are deployed for full coverage, an in ignorable number of devices cannot gain services. To solve this problem, the termed mobile ad-hoc networks (MANET) are proposed. A mobile ad-hoc network is an Infrastructure-less, self-organizing, and self-configuring network that allows mobile devices to cooperate with each other in order to gain permanent access. The accelerating development of real-time applications such as Internet of Things (IoT) adds new challenging goal which is providing high throughput through MANETs. This study aims to achieve the aforementioned goal by proposing Spatial Multiplexing-based MIMO solution. In Spatial Multiplexing-based MIMO, each transmitting antenna can independently transmit a unique data stream, which expected to increase total throughput. Ad-hoc on-demand distance vector (AODV) and destination sequenced distance vector (DSDV) routing protocols were selected as they are the most widely used reactive and proactive routing methods used with MANETs. We explain the proposed solution, then review results for feasibility assessment under four different scenarios using Network Simulator software. Based on the obtained results, the proposed solution led to improve throughput successfully when both protocols are assigned, however, throughput with AODV is much better under all conducted scenarios.
Predicting the strength of a plastic waste reinforced clay-sand soil mixture using BPNN approach
The study aimed to improve soil engineering properties by incorporating waste plastic bottle strips into the soil to enhance its strength. Plastic sheets of varying sizes an percentage were used, and a Back Propagation Neural Network (BPNN) was employed to predict unconfined compressive force. The model accuracy was confirmed by calculating mean absolute errors (MAE) of 0.00336, 0.0491, 0.0344, and 0.0461, indicating its reliability.
Copyright (c) 2024 International Journal of Engineering Research
Project Management Planning to Increase Company Resource Efficiency and Effectiveness in Indonesia
This study aims to develop global project management activities in the form of Work Breakdown Structure (WBS) and create project scheduling with Activity On Arrow (AOA) diagrams and barchart/gannt chart. So that with the preparation of the right WBS and AOA, the success of project management planning will be achieved. This research was conducted using a method starting from the findings of the problem, determining the research objectives, collecting and processing data, to the conclusion. The steps taken include: Perform (WBS) of project activities and create a sequence of project activities, so that they can be analyzed with (AOA), and barcharts. the following conclusions showed that Activity On Arrow takes 23 days to determine the HR requirements needed in the preparation of project management plans, while Barchart takes 23 days to determine the HR needed in the preparation of project management plans.
Developing an Empirical Correlation between DCPT Test Results and Relative Compaction for Sandy soils
The dynamic cone penetrometer (DCPT) is a simple portable in-situ testing instrument. It is usually used to measure the resistance of cohesionless granular soil. An attempt has been made to find a correlation between the DCPT results and the in-situ dry density for local Tripoli sand. Laboratory and fieldwork were carried out to investigate the relationship between the dry and wet densities and DCPT blow count (N10, Blows/100). In this study, the relationships between laboratory N10 and dry density were developed and verified. The work was conducted in two stages; in the first stage the samples were tested normally, while in the second stage the tests were conducted using surcharge load discs. Due to the lack of confinement at shallow depths, surcharge load disc was used on soil sample surface to evaluate the effect of the unconfinement on the results of the DCPT at the shallow depth (i.e. 250 mm to 300 mm). The test results in the first stage showed a good impression for the dry density of sandy soil (SP-SM) at depths greater than 250 mm. As results, the aid of the surcharge discs showed better trends. The validity of the proposed correlations was verified using test results on soils at new sites. The obtained results gave a more representative and reliable correlation. Measured densities versus estimated ones were plotted, shown the ability of the proposed correlation in estimating dry density from DCPT at proposed site. The proposed correlations are useful tools to help engineers in the practice to use in geotechnical investigation and to assess the dry density of soils.
Evaluating Geotechnical Engineering Properties of Sandy soil using Granulate Waste Tires
Used tires and scrap materials is environmental issue, cause and contribute to economic difficulties. It was necessary to find a safe ways to reduce the harm. This study was to investigate the impact of granulate waste tires as additive on the mechanical properties of silty sand soils through laboratory tests. Different percentages of granulate waste tires mixed added in 5%, 10%, 15% and 20% by a dry weight and the change in index properties were examined. It was noticed that there was a decrease in specific gravity from 2.57 to 2.04 at 20% whereas the California Bearing Ratio values of soaked and unsoaked condition decreased from 27% to 12% and from 37% to 10%, respectively as the granulate waste tires increased to 20%. Direct shear test results indicated that adding of granulate waste tires increased friction angle from 30.34o at 5% to 36.3o at 20% and reduced the cohesion values from 2.94 kPa to 0 kPa at 0% and 20%, respectively. Modified Proctor and vibrating compaction tests reveal that a little reduction in the maximum dry density as the waste tires increased by limiting the content of up to 20%. It is recommended to use the materials in construction projects such as low traffic road, car parking, and lightweight fill material behind retaining wall, reduces its impact on environment disposal of this hazardous harm waste material.
Field proving of a liquid displacement meter using Bi-directional Pipe Provers in Custody Transfer applications; case study of Libyan Zueitina Oil Port
In this paper, a field study is conducted on proving a positive displacement meter with bi-directional pipe provers to determine the repeatability of the meter's generated pulses and the deviation of the Meter Factor percentage during the Meter Proving process at Zueitina Oil Port in Libya. Equipment, procedures, requirements, national and international standards, and precautions that will ensure accurate metering of fluids were considered.
The effect of austenitizing temperature on thenormalising processing behaviour of 34CrNiMo6 steel
The aim of this study is to carry out research about the effect of austenitizing temperature of 34CrNiMo6 low alloy steel on the normalising heat treatment process. Moreover, a comparison of the austenite grain size that formed after the deformation at two austenitizing temperatures of 1100°C and 1200°C with that one resulted after the normalising process at temperature of 860°C. Moreover, to study the effects of increases of holding times of 6, 30 and 60 minutes at normalising process with both austenitizingon the grain size variation, and the consistency of microstructure, which in turn influences on the resulted mechanical properties. It was observed that deformation the specimens at austenitizing temperature of 1100 °C prior normalising process; gives a smaller grain sizes than those when using austenitizing temperature of 1200 °C. Furthermore, Increase in the normalising soaking times does have no influence the increasing of the grain size of austenite. However, it has an effect on The arrangement and shape of grains by making the grains equiaxed and creates a uniform structure. Furthermore, oxides scale thickness was observed at austenitizing temperature of 1200 °C, and particularly when soaking time at that temperature increased.
Normalizing, austenitizing and heat treatment
A Microcontroller-Based Face Recognition Attendance System
Attendance management system is an indispensable system by which every organisation tracks employees or students attendance. The manual process of marking attendance by using a paper-based or file-based system is susceptible to loss, falsification or disaster. One of the most interesting and important ways used in the past two decades in attendance management systems is the face recognition systems. This paper proposes a face recognition attendance system using ESP32-CAM development board, which is a low-cost microcontroller with built-in camera and Wi-Fi capability. The system captures and registers a facial image of a student, many student images are stored in the ESP32-Cam permanent internal storage. When attendance tracking is enabled, the face of a student in front of the camera will be detected and recognition process is performed where the tested image is compared with the stored images; once recognition is done, the recognized student data is sent wirelessly via http protocol to a MySQL database for further attendance report management.
ESP32-CAM , MySQL, IoT, Face Recognition
Microstrip bandpass filters based on spiral resonators are designed at 700MHz for 5G applications. In order to achieve size reduction, spiral resonators are used. The proposed filters are of third and fifth orders. The filters are printed on FR4 substrate with thickness of 1.6mm and dielectric constant of 4.5. The filters are simulated using CST electromagnetic simulator. The simulated results show that the presented filters exhibit good return losses, low insertion losses within the passband. Furthermore, a good selectivity is obtained. The simulated reflection coefficients are -15 dB and -12 dB for the 3rd and 5th order filters respectively. The fifth order bandpass filter provides higher selectivity but higher insertion loss as expected.
Performance Analysis of Awbari Gas Turbine Power Plant with Crude Oil
The performance of a gas turbine can be evaluated by its efficiency and net power output which both are affected by ambient conditions (atmosphere air temperature and humidity) and used fuel.In this work, the performance of the gas turbine (SGT5-2000E) has been modelled using HYSES ASPEN software and evaluated by assessing the efficiency, net power, specific fuel consumption (SFC), and fuel-air-ratio (FAR) in a hot weather region at sea level (the Sahara Desert in Libya ). Evaluation of the performance of SGT5-2000E (Awbari gas turbine power plant, south of Libya) has been carried out by modelling the units of the power plant using HYSYS ASPEN and validated against the design data provided by the manufacturer. In addition, two performance scenarios (two different fuels) were drawn for the gas turbine power plant. The first is at a fixed Pressure Ratio (PR) of 12 with a variation of the compressor inlet temperature (CIT)between 0 oC and 50 oC, and the second is at a fixed CIT of 15 oC with a variation of PR ranging from 7 to14 bar. Additionally, a performance analysis of the Awbari power plant is performed based on CIT and PR. The results show that the CIThas a linear effect on the turbine’s efficiency, while the PR has a non-linear effect on the turbine's efficiency. The effect of PR on the net power at fixed CIT has different behaviour depending on its CIT. For different CIT values, the net power reaches the peak at the PR values between 9 and 12. Moreover, using Natural gas as fuel for gas turbine units promotes proper turbine performance compared with crude oil as fuel.
Gas turbine, Hysys Aspen, SGT5-2000E, modelling and simulation
Bearing Misalignment and Eccentric Wear: A Study on Condition Monitoring
This study investigates ball bearing failures and evaluates the performance of various methods for detecting such failures. Experimental tests were conducted on a motor-generator system supported by ball bearings, where several types of real-time faults were intentionally introduced. Vibration signals were collected to capture the early stages of bearing faults. The monitored vibrations successfully predicted impending failures in the outer race, inner race, and ball of the bearings. To assess the effectiveness of the prediction methods, different stages of fault development were considered. Additionally, the feasibility of implementing these techniques in real-world systems and real-time applications was examined. The vibration monitoring technique proved to be suitable for analysing various defects in bearings and providing early indications of malfunction. Vibration measurements were recorded at each housing of the rotor bearings. The results indicated that a deteriorating or faulty ball bearing had a significant impact on the vibration spectra. To identify different defects in ball bearings, time domain, frequency domain, and Fast Fourier Transform (FFT) analysis were employed. The findings demonstrated the usefulness of each of these techniques in detecting problems associated with ball bearings.
Condition Monitoring, Bearings, Bearing faulty, Vibration analysis
Design and Implementation of an Innovative Balun Configuration for Planar Antenna Use
The main parts of balanced circuits, including push-pull amplifiers, balanced mixers, frequency multipliers, and antennas, are baluns. Due to the increased integration of most of these applications, baluns must be inexpensive and of small size. This research paper presents a novel method for designing planar baluns. The approach begins by examining a symmetrical 4-port network features an open-circuit termination on one port, utilizing both even and odd mode stimulations. The suggested balun, supported by comprehensive design equations, showcases a completely balanced output and excellent input alignment, with measurement outcomes aligning closely with the simulated values.
: balun planar lumped distributed even-odd mode
A Comparative Study of Field Oriented and Backstepping Control Strategies for Wind turbine PM Synchronous Generator
In this paper, a comparative study of Field Oriented Control and Backstepping Control methods has been conducted to control a Permanent Magnet Synchronous Generator for wind power application. These control strategies are described and designed, then implemented using the Matlab/Simulink environment. Finally, the two different strategies are compared in response to active power, current, voltage, electromagnetic torque, and rotor speed. FOC allows us to independently control the torque and the flux of our machine in the same way as a DC machine with separate excitation, where the inducing current controls the magnetic flux, and the induced current controls the electromagnetic torque. We transformed the stator instantaneous currents to two current components, one which controls the flux (along the d axis), and the other controls the torque (along the q axis). The adaptive Backstepping control relies on the nonlinear model of the controlled system. It harnesses the principles of the Lyapunov stability theory to regulate various parameters and uphold the overall system’s stability. The findings of this research showed that firstly, backstipping control method is faster, less ripple, and more stable than the FOC method. Secondly, the THD in FOC method is higher than in backstipping control method. Finally, both control techniques have sinusoidal current and voltage waveforms. So, they can satisfy the grid code.
Wind turbine generator, PM synchronous generator control, Field oriented control, backstepping control
Detection and Diagnosis of Brain Tumor using Convolutional Neural Networks
Brain tumors are one of the major health problems related to abnormalities in the human brain. An activist diagnosis of brain tumors is critical to improve patient outcomes and lives. Early detection of tumors is crucial for treatment. Magnetic Resonance Imaging (MRI) is one of the most commonly used diagnostic methods for brain tumors in the clinical area. Manual detection of brain tumors is becoming increasingly time-consuming and costly. Therefore, an automated Computer Aided Diagnosis (CAD) system is needed to help doctors and radiologists detect these deadly tumors in time, thereby saving precious lives. Convolutional Neural Networks (CNNs) are widely used in various CAD systems. CNNs play an important role in healthcare as image processing techniques for segmentation, recognition, and classification of MRI images and classification and detection of brain tumors. This paper applies the Deep Learning (DL) architectures for brain tumor detection and classification. Implement a deep learning (CNN) based computational approach that includes image pre-processing to extract regions of interest in the image itself to identify and detect tumors in the brain. The highest accuracy rate in the experiment reached 96%. Evaluation metrics used include sensitivity, precision, loss, and F1 score. The results obtained will aid in the diagnosis and detection of brain tumors.
Copyright (c) 2023 International Journal of Engineering Research
Effect of variable parameters on the performance of gas turbine cycle
The gas turbine are being usually used in several application such as aircraft engine and electricity power station plants. To improve its performance many researches has been performed. In this study the thermodynamic analysis has been carried out of a gas turbine power plant located at the sea level in Rasanuf city ( north of Libya ), based on the conservation of energy to evaluate its efficiency, net power and specific fuel consumption. The analysis of thermodynamic equations of first law performed depending on the variable parameters (atmosphere air temperature, pressure ratio) at fixed turbine inlet temperature (TIT) for 1000 K, 1200 K, and 1500 K, compressor pressure ratio from 4 to 20 and ambient temperature 15 oC to 45 oC.
Calculating the Ultimate Bearing Capacity of a Strong Soil Layer over a Weak Soil Layer
The ultimate bearing capacity calculations for shallow footings in two-layered soil systems hinge on the underlying failure surface pattern. his study examines scenarios observed in nature, where strong soil overlays a weaker layer within layered soils, specifically focusing on square footings and calculation of the ultimate bearing capacity value using different theoretical equations according to the approaches of the scientists Terzaghi, Hansen, Meyerhof, and Vesic. an analysis of the values of the results and compared with each other. Presented the results of the study for the ultimate bearing capacity of layered [C - Ꝋ] soils are stronger than all studied soils cases and the ultimate bearing capacity of sandy layered soils is times stronger than the ultimate bearing capacity of clayey layered soils, As that ultimate bearing capacity of clayey layered soils is weaker than all studied soils cases.
Effectiveness of Rehearsal Mechanism on CAD Learning Performance with Using Interactive Multimedia
This study was seeks to examine the effects of the rehearsal mechanism on the new CAD learner’s practice performance (PP). An attempt was made to establish if rehearsing the CAD information increased the learners’ retention and improved their practice performance over those who did not rehearse. 29 new CAD learners were the participants in this study and were randomly divided into approximately two equal groups. Group one had rehearsed the CAD information over time (three times during one week only), while the other group did not rehearse the CAD information at all. Both groups were asked to created identical CAD tasks by following the same CAD multimedia presentation of an interactive media of ‘audio and animation’ modes. The results indicated that the rehearsal mechanism shortened the learning time and enhanced drawing accuracy, in contrast to the non-rehearsal option.
Graduates Skills Developments for Libyan Labour Market
Any educational program's outcomes can be described in terms of both knowledge and skills. Chemical engineering graduates' skills and abilities might include those unique to managing material and energy balances and problem-solving skills that are generic or transferrable. This paper is concerned mainly with personal or transferable skills. It is widely acknowledged that one of the most critical abilities for chemical engineering graduates is the ability to communicate well in several written and spoken formats. The ability to work effectively in groups; be proactive and initiative in problem-solving; be numerate and IT literate; and ability to manage oneself and continue to learn are all desirable qualities. In some particular instances, it is illustrated that within our chemical engineering programme at Elmergib University, there are various and different chances to acquire these abilities in order to satisfy the demands of Libyan industries. This research considers how transferable skills can be defined and prioritized and then developed within the chemical engineering curriculum. A systematic strategy was designed to determine where and how skills can be managed and integrated into the curriculum. Chemical engineering graduates from Elmergib University were solely satisfied with their decision to pursue a degree in the field.
chemical engineering graduates; transferable' personal' skills; degree programs; engineering curriculum development; employer.
Flat open-ended coaxial sensors are increasingly popular for numerous measurement techniques, as a non-destructive method, due to the increased sensitivity and contrast obtained at microwave frequencies. The flat aperture of the sensor limits the practical application of such a method, particularly in diagnosis. In this paper, an elliptic aperture coaxial sensor with small dimensions is introduced and numerically analysed. Using finite element method, the radiation from the elliptical aperture into a two-layer dielectric medium is examined. Explicit contrast of reflection coefficient in both magnitude and phase, and high sensing depth are obtained with such a sensor aperture at low microwave frequencies of 0.1, 0.3, 1, and 3 GHz.
Elliptic aperture coaxial sensor, A two-layer dielectric medium, Reflection coefficient
Electromagnetic Radiation Measurements from Mobile Base Stations in Sirte
The main objective of this work is to evaluate the power radiated from mobile base stations by measuring the power density of chosen base stations on particular schools and sites of local communication networks in Sirte city. The measurements were conducted on three schools on which mobile phone base stations were installed and three open greenfield areas; the measurement was performed at different distances and directions from mobile base stations using RF Field Strength Meter instrument. The measured data were compared with International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines, to ensure that the radiation levels are within the permitted levels.
EM radiation, base station radiations, EM hazard, ICNIRP, Power Density
Cloud Computing and Artificial Intelligence: A Scoping Literature Review
In the past two decades, Cloud Computing (CC) and Artificial Intelligence (AI) technologies have witnessed amazing growth, and the majority of organizations and companies around the world have become more aware of the importance of these technologies. AI and CC together are often referred to as the "AI cloud". Using AI in the cloud can improve cloud performance and efficiency while driving digital transformation in enterprises and making business operations more efficient and strategic, while also providing additional flexibility, agility, and cost savings. As a result, AI helps make the complex processes of the AI cloud better. Academics from different fields of expertise try to solve cloud-related problems; there are an increasing number of studies underway in CC service formation and AI applications. This paper will discuss some theoretical points of view, the impact of using AI in the cloud field, and discover the most important AI techniques used to find solutions to various challenges related to the cloud.
Cloud Computing، Artificial Intelligence, AI Cloud
Impacts of U and Inverted U-Bends on Vertical Gas-Liquid Two-Phase Fluids
The current work is experimentally based which is conducted on the purpose of studying the impacts of U and inverted U-bends on gas/liquid behavior in a vertical upward and downward flow line. The main instruments used are wire mesh sensor (WMS) and liquid film probes. Both devices are installed at the top and bottom locations of upward and downward sections. Probability density functions (PDFs) and time traces of averaged void fraction are applied to reveal the flow behavior inside this configuration. It is very obvious from achieved results that the flow structure in the adjacent parts of the bends is significantly different from those apart away. These bends act on distribution of the flow and change it from uniform to un uniform in adjacent straight sections of the pipeline. This is attributed to the action of centrifugal and gravitational forces that generated by the bends. The results are further explained by analysis the reconstructed images obtained from Wire Mesh Sensor technique, and circumferential distribution of liquid film that measured by conductive film probes. The data of liquid film profile are consistent with PDFs and time traces data extracted by WMS.
Downward, Upward, 180o Bend, Film Thickness Probes, Wire Mesh Sensor
Use of Tefla as Partial Replacement of Cement in Concrete Mix
Abundant is tefla (Yellow Tefla, Green Tefla) in OmAlrozam, a town near the city of Derna, Libya. Cement is one of the components of concrete plays a great role in the construction industry. Higher consumption of cement in the construction industry leads to higher pollution. To make economic aspects in the construction industry and protecting the environment from pollution and also cement production emits CO2 into the atmosphere which is harmful to nature. If we can partially replace the cement with the material with desirable properties then we can save natural material and reduce the emission of CO2 into the atmosphere. This study aimed to investigate the suitability of using tefla in concrete. The tefla were ground to roughly cement fineness, which has been sieved and passing through 90 microns and after grinding, the chemical composition of the tefla material was determined using X-Ray Fluorescence (XRF). Four replacement levels,5%,10%,15% and 20% with a w/c ratio of 0.50. The workabilities of the fresh concrete mixes were evaluated using the slump test while compressive and splitting tensile strengths of hardened concrete were evaluated at different curing periods of 3, 7, 14 and 28 days, the workability of the concrete reduce with an increase in tefla powder content. Better result in mechanical properties (compressive strength and splitting tensile strength) and physical properties (water absorption and porosity) of the concrete was achieved at 5% cement replacement of yellow tefla, after which a decrease in strength with increasing tefla content was recorded. The use of yellow tefla of not more than 5% was recommended for concrete production.
Application of Genetic Algorithms to Estimate Preventive Maintenance Interval: A Pump Device as a Case Study
Genetic Algorithms is one of the techniques which has been applied in recent years to contribute to the scheduling of Preventive Maintenance (PM) to improve the whole system performance and run efficiently and effectively. This paper aims to estimate the interval of preventive maintenance for any processing equipment using genetic algorithms. A centrifugal pump is presented as critical equipment to apply a genetic algorithm to prolong the interval of PM. The obtained results show that a genetic algorithm is effective and practical in estimating the optimum time of preventive maintenance for centrifugal pumps.