International Journal of Engineering Research in Africa最新文献

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The Bond Length of Intermetallic Ternary Phases of Al-Fe-Si Alloy Using Molecular Dynamics Simulation with the Application of [001] Compression Al-Fe-Si合金金属间三元相键长分子动力学模拟[001]
International Journal of Engineering Research in Africa Pub Date : 2023-09-12 DOI: 10.4028/p-h1e28w
Meryem Taoufiki, Hanae Chabba, Abderrahim Barroug, Ahmed Jouaiti, Driss Dafir
{"title":"The Bond Length of Intermetallic Ternary Phases of Al-Fe-Si Alloy Using Molecular Dynamics Simulation with the Application of [001] Compression","authors":"Meryem Taoufiki, Hanae Chabba, Abderrahim Barroug, Ahmed Jouaiti, Driss Dafir","doi":"10.4028/p-h1e28w","DOIUrl":"https://doi.org/10.4028/p-h1e28w","url":null,"abstract":"The research on tolerance stress in aluminum alloys is focused on examining the mechanical behavior of τ 4 -Al 3 FeSi 2 and τ 12 -Al 3 Fe 2 Si phases during [001] compression and their structural evolution. The use of MD computational bond length measurements allows for a comparison to be made with previous studies on tensile deformation. The simulations were performed at a constant strain rate of 21×10 10 s -1 , using NPT conditions (isothermal-isobaric), with approximately 20,000 atoms, 1 atmosphere of pressure, and 300 K temperature, using a Nosé-Hoover thermostat. Under periodic boundary conditions, the Modified Embedded Atoms Method (MEAM) potential was applied to all 3D faces, and the average bond length behavior between Al, Fe, and Si was calculated. A comprehensive investigation is carried out to explore the properties of these phases, including a detailed structural analysis at the atomic scale. This paper presents a comprehensive analysis of how changes in compound concentration affect mechanical behavior during compression. The average bond length varies depending on the applied stress axis, and it demonstrates good agreement with literature data. The mechanical deformations alter the behavior of atomic phases, as discussed in detail in the conclusion.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Application of a Modified Particle Swarm Optimization for Maximum Power Point Tracking for Solar Photovoltaic Systems 修正粒子群算法在太阳能光伏系统最大功率点跟踪中的应用
International Journal of Engineering Research in Africa Pub Date : 2023-09-12 DOI: 10.4028/p-j0mfd9
Edemialem Gedefaye, Samuel Lakeou, Tassew Tadiwose, Tefera Terefe
{"title":"Application of a Modified Particle Swarm Optimization for Maximum Power Point Tracking for Solar Photovoltaic Systems","authors":"Edemialem Gedefaye, Samuel Lakeou, Tassew Tadiwose, Tefera Terefe","doi":"10.4028/p-j0mfd9","DOIUrl":"https://doi.org/10.4028/p-j0mfd9","url":null,"abstract":"The maximum power point extraction at any instant of time on photovoltaic (PV) systems has attracted attention. This study introduces a novel DC-DC converter-based power point tracking (PPT) algorithm for solar PV systems. The proposed optimization technique is a modified form of the standard particle swarm optimization (PSO), where the limitations of the standard PSO algorithm, like random number assignment of the acceleration factors and constant weight, are modified. The main goal of the suggested modified particle swarm optimization (MPSO) algorithm is to change the particle weight within a range of values and remove the random number from the acceleration factors. As a result, some of the contributions to this work are: First, when the weight is within some interval values, velocity restriction with a constant number improves. It offers the chance to expedite the search without limitation because of the constantly shifting environmental conditions. Second, the solution shows that the lack of acceleration constants predicts the particle's behavior. Thirdly, the algorithm's input parameters are incredibly minimal. The MATLAB/Simulink simulation of a modeled standalone 2.9 kW solar PV system in shading and non-shading conditions proved the proposed algorithm's performance. Thus, the average efficiency and time tracking of the global maximum power point (GMPP) is 99.45% and 6.285 s, respectively. Generally, the proposed MPPT method is more straightforward and adaptable than perturb and observe (P&O), the cuckoo search algorithm, and standard PSO.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Numerical Simulation of Geotechnical Isolation of Building Subjected to Earthquake Using Rubber Sand Mixtures 橡胶砂混合料对地震作用下建筑物岩土隔震的数值模拟
International Journal of Engineering Research in Africa Pub Date : 2023-09-12 DOI: 10.4028/p-amzl3q
Ali Brara, Djamalddine Boumezerane
{"title":"Numerical Simulation of Geotechnical Isolation of Building Subjected to Earthquake Using Rubber Sand Mixtures","authors":"Ali Brara, Djamalddine Boumezerane","doi":"10.4028/p-amzl3q","DOIUrl":"https://doi.org/10.4028/p-amzl3q","url":null,"abstract":"The use of recycled rubber in various civil engineering applications has seen a considerable rise in recent years. The rubber-soil mixture can exhibit a higher energy absorption capacity than soil alone, which would reduce the energy applied to structures, the stresses, and shocks they undergo. Base isolation is the process of isolating the base of a structure to limit the effects of earthquakes, so that the seismic forces applied to the base of the bedrock cannot move with the same intensity towards the super structure.In this work, the beneficial effects of rubber mixtures (RSM) in mitigating earthquakes when these mixtures are inserted as layers in the soil profile are highlighted; the approach is based on a method of using worn tires for seismic protection applications for infrastructures subjected to seismic loads. It involves mixing particles from used tires with soil materials and placing the mixtures under the foundation of the building as geotechnical insulation systems for vibration absorption.The foundation of a four-storey building is implanted in a soil profile in which a layer of rubber-sand mixture (RSM) has been inserted; to perform the role of seismic isolation when subjected to seismic excitation.The investigation is focused on the variation in the thickness of the layer on the one hand (between 1m and 4m), and on the other hand on the position of this layer in the soil mass (top, middle and bottom of the profile).The peaks of horizontal accelerations recorded at the base and top of the structure show that the sand-rubber mixture has adequate and promising potential for their application as seismic isolation materials for low-rise buildings. Moreover, the thickness of the layer and its location are two very determining parameters in the improvement of the performances of these RSM mixtures, especially in terms of reduction of the acceleration peak recorded.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135886957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Experimental Investigation to Optimize Build Orientation and Raster Angle for PLA and ABS Specimens Generated by FDM Technology 优化FDM技术生成PLA和ABS试样的构建方向和光栅角度的实验研究
IF 0.7
International Journal of Engineering Research in Africa Pub Date : 2023-08-08 DOI: 10.4028/p-5vBIxb
A. El Azzouzi, H. Zaghar, L. Lasri, N. Moujibi
{"title":"Experimental Investigation to Optimize Build Orientation and Raster Angle for PLA and ABS Specimens Generated by FDM Technology","authors":"A. El Azzouzi, H. Zaghar, L. Lasri, N. Moujibi","doi":"10.4028/p-5vBIxb","DOIUrl":"https://doi.org/10.4028/p-5vBIxb","url":null,"abstract":"The fused deposition modeling (FDM) process is used increasingly in the manufacture of mechanical parts and more particularly in the automotive and aeronautical fields. The purpose of this work is to optimize build orientation for obtaining polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) samples with the best mechanical properties, dimensional accuracy, surface quality, and minimal total cost. For achieving This, PLA and ABS specimens are fabricated by FDM technology with three build orientations (flat, on edge, upright) and three raster angles (0°, 45°, 90°).at first, the dimensions of the produced samples are measured .secondly, the tensile test, DETLAB equipment was used to obtain tensile stress. In addition, roughness testers were also used to measure surface quality. As a consequence, the findings indicate that the mechanical strength increases with decreasing raster angle and by aligning from upright to flat orientation for both materials due to the fracture mechanism and loading direction. Also, the manufacturing orientation and raster angles significantly affected the dimensional accuracy and total cost. Additionally, there was a big difference in the surface roughness depending on the manufacturing orientation and raster angle; perpendicular measurements increase surface roughness values. We aim to investigate the impact of flat, on-edge, and upright build orientations as well as raster angles on the total cost, tensile strength, dimensional accuracy, and surface roughness of PLA and ABS material through tensile experiments.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"65 1","pages":"1 - 20"},"PeriodicalIF":0.7,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44326489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Application of the AM2 Model to Simulate Anaerobic Digestion of Municipal Solid Waste AM2模型在城市生活垃圾厌氧消化模拟中的应用
IF 0.7
International Journal of Engineering Research in Africa Pub Date : 2023-08-08 DOI: 10.4028/p-G7Pjt2
Amine Hajji, Y. Louartassi, M. Garoum, N. Laaroussi, M. Rhachi
{"title":"Application of the AM2 Model to Simulate Anaerobic Digestion of Municipal Solid Waste","authors":"Amine Hajji, Y. Louartassi, M. Garoum, N. Laaroussi, M. Rhachi","doi":"10.4028/p-G7Pjt2","DOIUrl":"https://doi.org/10.4028/p-G7Pjt2","url":null,"abstract":"Anaerobic digestion is a promising technology due to its significant economic and environmental potential. Nevertheless, its development is a substantial challenge for researchers since this biochemical process is difficult to predict due to the many reactions involved. Thus, mathematical modeling becomes necessary to analyze the fermentation process and determine the complex kinetic parameters to identify and predict the system's performance under the most varied conditions. This research aims to apply the AM2 model to simulate the anaerobic digestion process of municipal solid waste. The experimental results obtained from our previous research work were used for identifying the parameters of the AM2 model and for its validation by the cross-validation method. Simulations showed that the model could effectively reproduce the dynamics of the evolution of the anaerobic digestion process with reasonable accuracy.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"65 1","pages":"21 - 34"},"PeriodicalIF":0.7,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46539618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Valorization of Moroccan Hemp Waste: Study of the Possibility of its Use in Thermal and Acoustical Insulation of Buildings 摩洛哥大麻废料的价值化:用于建筑物隔热和隔音的可能性研究
IF 0.7
International Journal of Engineering Research in Africa Pub Date : 2023-08-08 DOI: 10.4028/p-Wa98e1
Oussama Zine, D. Taoukil, Mohamed Ouakarrouch, I. El abbassi, E. Kadri, Mohammed lhassane Lahlaouti, A. El bouardi
{"title":"Valorization of Moroccan Hemp Waste: Study of the Possibility of its Use in Thermal and Acoustical Insulation of Buildings","authors":"Oussama Zine, D. Taoukil, Mohamed Ouakarrouch, I. El abbassi, E. Kadri, Mohammed lhassane Lahlaouti, A. El bouardi","doi":"10.4028/p-Wa98e1","DOIUrl":"https://doi.org/10.4028/p-Wa98e1","url":null,"abstract":"This paper aims to study the possibility of valorizing hemp residues in order to develop new local bio-composites from Moroccan hemp shiv and epoxy. The goal is to use them as thermal and acoustical insulation panels since these hemp residues exist in large quantities in landfills and present a national concern due to a lack of waste management technologies. For this purpose, several samples were prepared for different densities and two sizes of hemp shiv; crushed shiv (CS) and fibred shiv (FS). The results revealed that the increase of density resulted in an increase in thermal conductivity and a decrease in thermal diffusivity. However, the thermal conductivity of composites is still lower than 0.1 W/mK for the most studied samples. The samples show values of acoustic absorption coefficients varying between 0.2 and 0.59 for crushed shiv composites (CSC) at the frequency range (578-1396 Hz) and between 0.2 and 0.73 at the frequency range (662-1396 Hz) for Fibred shiv composites (FSC). It has been observed that the density has a significant effect on the sound absorption coefficient. Increasing the density shifts the acoustic absorption curve towards the low frequencies. Also, decreasing the particle size enhances the sound absorption in the medium frequency range (300-600 Hz). The obtained results are satisfactory for manufacturing these new composites that can be used as thermal and acoustic insulators. Moreover, it offered the best solution for hemp waste management.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"65 1","pages":"35 - 54"},"PeriodicalIF":0.7,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46301268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Performance Evaluation of Hydroponics Control Systems for pH, Temperature, and Water Level Control 酸碱度、温度和水位控制水培控制系统的性能评价
IF 0.7
International Journal of Engineering Research in Africa Pub Date : 2023-08-08 DOI: 10.4028/p-RBT3yU
M. Rathedi, O. Matsebe, N. Ditshego
{"title":"Performance Evaluation of Hydroponics Control Systems for pH, Temperature, and Water Level Control","authors":"M. Rathedi, O. Matsebe, N. Ditshego","doi":"10.4028/p-RBT3yU","DOIUrl":"https://doi.org/10.4028/p-RBT3yU","url":null,"abstract":"This study evaluates different control algorithms used in a hydroponic farming system to improve the quality of farm produce and resource efficiency. It focuses on three key hydroponic control parameters(potential hydrogen (pH), water level, and temperature control). Mathematical models are derived from the literature to represent hydroponic environments. These models are used for simulation purposes in MATLAB software to implement various control algorithms to evaluate their performance against each other and the system requirements utilizing transient performance parameters. Transient performance parameters are overshoot, settling time, rise time ,and steady-state error. The various control algorithms are fuzzy logic (FL), Proportional Integral Derivative (PID), and Proportional Integral Derivative-Fuzzy logic controller (PID-FL). This paper examines the performance of the hybrid PID-FL controllers compared to the most commonly used fuzzy logic and PID controllers. The result of the work shows that PID-FL is generally better for all the system models, making it more applicable.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"65 1","pages":"105 - 116"},"PeriodicalIF":0.7,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45782906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Overall Equipment Efficiency Improvement through a Lean Approach in SME: A Case Study 中小企业通过精益方法提高整体设备效率的案例研究
IF 0.7
International Journal of Engineering Research in Africa Pub Date : 2023-08-08 DOI: 10.4028/p-1zhmXC
Amr Dahab, Mohammad Abdulwahed Younes, S. Backar
{"title":"Overall Equipment Efficiency Improvement through a Lean Approach in SME: A Case Study","authors":"Amr Dahab, Mohammad Abdulwahed Younes, S. Backar","doi":"10.4028/p-1zhmXC","DOIUrl":"https://doi.org/10.4028/p-1zhmXC","url":null,"abstract":"Lean manufacturing could enhance the overall equipment efficiency (OEE) by decreasing process setup, changing over time, and eliminating unnecessary activities. Meanwhile, Lean quality tools and standard work procedures implementation increase daily production. This study investigates the role of Lean manufacturing in enhancing environmental performance besides the operational one relating to small- and medium-sized enterprises (SMEs) in manufacturing firms through a Lean framework compatible with any firm's limited resources and experience. The study uses tools that small enterprises could apply, such as project charter, value stream maps, and 5S, accompanied by a Kano questionnaire and market analysis. The study has been validated in a small-sized Egyptian candle manufacturing enterprise and successfully implemented. It was possible to increase daily production by 31.95%, reduce cycle time by 19.82%, increase inspection and packaging overall efficiency by 10%, and decrease raw material waste by 29.6%.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"65 1","pages":"117 - 129"},"PeriodicalIF":0.7,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49307064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Laboratory Geotechnical Investigations on Five Silty Soils Sampled along the Banks of the Lubumbashi River/Haut-Katanga/DR Congo 对卢本巴希河沿岸/上加丹加/刚果民主共和国五种粉质土壤取样的实验室岩土工程调查
IF 0.7
International Journal of Engineering Research in Africa Pub Date : 2023-08-08 DOI: 10.4028/p-3hLFCa
Yannick Kiyukeno, Gustave Mukoko, B. François
{"title":"Laboratory Geotechnical Investigations on Five Silty Soils Sampled along the Banks of the Lubumbashi River/Haut-Katanga/DR Congo","authors":"Yannick Kiyukeno, Gustave Mukoko, B. François","doi":"10.4028/p-3hLFCa","DOIUrl":"https://doi.org/10.4028/p-3hLFCa","url":null,"abstract":"An adequate design of port structures along waterways requires a good knowledge of the geotechnical properties of the surrounding soils. This study aims to characterize the geotechnical laboratory properties of alluvial soils along the Lubumbashi river (section between the Tshombe and Tshondo bridges, approximately 3 km long) in the city of Lubumbashi, province of Haut Katanga in DR Congo. To meet this objective, five sampling zones were selected from which samples were taken with a hand auger and various geotechnical laboratory tests were performed. Identification tests reveal that the tested soils have low to moderate plasticity and are in the range of sandy silt to silty sand with a low fraction of clay particles, essentially inactive. Oedometric compression tests reveal that the soils in place are (moderately) compressible. The consolidated undrained (CU) triaxial compression and direct shear tests indicate effective values of internal friction angle and negligible drained cohesion that, are consistent for this kind of soil. In the end, the compressibility and strength parameters of the five tested soils are correlated with their plasticity index, showing a decrease in the shear strength and an increase in the compressibility when the plasticity index increase.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"65 1","pages":"73 - 89"},"PeriodicalIF":0.7,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43112403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
International Journal of Engineering Research in Africa Vol. 65 非洲工程研究国际期刊》第 65 卷
IF 0.7
International Journal of Engineering Research in Africa Pub Date : 2023-08-08 DOI: 10.4028/b-xes6du
A. O. Ibhadode
{"title":"International Journal of Engineering Research in Africa Vol. 65","authors":"A. O. Ibhadode","doi":"10.4028/b-xes6du","DOIUrl":"https://doi.org/10.4028/b-xes6du","url":null,"abstract":"","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":"19 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139351410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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