International Journal of Engineering Research in Africa最新文献

{"title":"Model-Based Approach for Leak Detection and Localization in Water Distribution Networks: A Literature Survey","authors":"T. Shabangu, Y. Hamam, J. Jordaan, K. Adedeji","doi":"10.4028/p-r2lbNg","DOIUrl":"https://doi.org/10.4028/p-r2lbNg","url":null,"abstract":"Water loss poses a significant problem for water utilities and has received a lot of attention. To fulfill the increasing global demand for water, water supply system operations must be streamlined, making leak detection and location crucial. Water utilities have developed a number of techniques over time for finding leaks in water distribution networks (WDNs). These methodologies range from simple visual inspection to the use of hardware systems and now software using models and algorithms. Data from flow or pressure measurements, which are required for the analysis of water networks, is becoming more readily available with the introduction of intelligent sensor devices. Along with the introduction of geographic information systems (GIS) and supervisory control and data acquisition (SCADA) in the water sector, the deployment of model-driven methodologies for leak detection and localization has found extensive use. This paper aims to provide a concise introductory reference for early researchers in the development of a model-based approach for leak detection in WDNs. Thus, a survey of model-based approaches is presented, along with current research trends and applications of model-driven methodologies for leak detection in water supply networks. Several model-driven approaches and research studies for each case are discussed. Some challenges and research gaps are also discussed.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139175057","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}

{"title":"Analysis of a Hybrid System Solar Chimney-Air Soil Heat Exchanger for Natural Ventilation","authors":"Billal Belfegas, Tahar Tayebi, Salah Larbi","doi":"10.4028/p-3elgvg","DOIUrl":"https://doi.org/10.4028/p-3elgvg","url":null,"abstract":"The current study looks at a hybrid passive cooling system that combines a solar chimney with an earth-to-air heat exchanger (EAHE) usually called Canadian Well. Numerous experimental and numerical examinations with various applied radiation heat fluxes were carried out to evaluate its ability to cool a room. Glass temperature, wall temperature, air flow mean temperature, hourly rate of air exchange (ACH), outlet airflow velocity, and rate of air mass flow were determined experimentally and numerically, and validated against previously published experimental and analytical works. It was found that the chimney's operation is dependent on the radiation intensity. The EAHE has reduced the room's temperature by improving exchanges with the solar chimney. The comparison of experimental and numerical data for different radiation intensities reveals that the best diameter of the tube of the underground heat exchanger for the proper operation of our system is d = 0.04m. The efficiency of our system increases as the radiation increases, causing an increase in the temperature of the absorber, which influences the air temperature in the chimney.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878045","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}

{"title":"Characterization of Boeing 777 Nose Landing Gear to Better Withstand Rough Landing","authors":"Abdulbaqi Jinadu, Olalekan Adebayo Olayemi, Quadri Tijani, Abdulwasiu Salaudeen","doi":"10.4028/p-fg9nj7","DOIUrl":"https://doi.org/10.4028/p-fg9nj7","url":null,"abstract":"An important role a landing gear plays is that it aids in the landing and takeoff of aircraft. The landing gear must be designed in such a way that it can take these stresses in static and dynamic situations. This is to accommodate both rough and smooth landings that result from various loads acting upon it, such as drag force, vertical load, and side load. In the aviation industry, landing gear stress is a key concern, and different research in this field has previously yielded excellent results. However, the time has come to raise the bar even higher. This report will focus on the optimization of the Boeing 777's nose landing gear to better withstand rough landings. During the timeframe of this research, SOLIDWORKS was utilized to model and analyze various components of the landing gear. The results summarize that a single material should be avoided throughout the components of the landing gear. Components such as pistons with a larger stress allocation should be made of titanium alloy, while components with a lesser stress allocation should be made from aluminum alloy.Abstract. An important role a landing gear plays is that it aids in the landing and takeoff of aircraft. The landing gear must be designed in such a way that it can take these stresses in static and dynamic situations. This is to accommodate both rough and smooth landings that result from various loads acting upon it, such as drag force, vertical load, and side load. In the aviation industry, landing gear stress is a key concern, and different research in this field has previously yielded excellent results. However, the time has come to raise the bar even higher. This article will focus on the improvement of the Boeing 777's nose landing gear to better withstand rough landings. During the timeframe of this research, motion study in SOLIDWORKS 2020 (Stand-alone license) was utilized to model and analyze various components of the landing gear. The results summarize that a single material should be avoided throughout the components of the landing gear. Components such as pistons with a larger stress allocation should be made of titanium alloy, while components with a lesser stress allocation should be made from aluminum alloy.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135879120","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}

{"title":"New Selection Process for Retaining Walls Based on Life Cycle Assessment and Economic Concerns","authors":"Hend Zbidi, Saloua El Euch Khay","doi":"10.4028/p-ovz45x","DOIUrl":"https://doi.org/10.4028/p-ovz45x","url":null,"abstract":"Earth-retaining walls (ERWs) are widely used structures in civil engineering, a field known for their substantial environmental impact. However, the current practice of selecting ERW types for a project often neglects environmental concerns. To address this issue, this study proposes a novel process to enhance the rationality of ERW selection. It involves assessing the performance of commonly used ERW types in terms of both environmental issues and economic considerations. The proposed process relies on calculating a total cost (TC), which incorporates the costs of two crucial environmental indicators: carbon dioxide (CO 2 ) emissions and cumulative energy demand (CED), evaluated using life cycle assessment (LCA), in addition to considering the traditional construction cost of the ERW. By determining the TC for various retaining wall options, engineers can identify the optimal ERW type for a specific project. To validate the effectiveness of this environmental-economic approach, a case study was conducted comparing two ERW types: the conventional concrete-reinforced retaining wall (CRRW) and the geosynthetic-reinforced retaining wall (GRRW). The study evaluated structures constructed at four different heights, ranging from 3 m to 6 m. The results demonstrate that the GRRW is the optimal option, offering a lower TC than the equivalent wall conventionally built with reinforced concrete across all evaluated heights. However, the difference in TC between the two ERWs is more pronounced for taller walls. At a height of 3 m, the total cost ratio between the CRRW and the GRRW is moderate at 1.2, while it substantially increases to 2.5 at a height of 6 m. In conclusion, the proposed process was effectively applied to the case study, providing valuable insights into the assessment of earth-retaining structures from both environmental and economic perspectives. It can assist engineers in prioritizing and selecting the most sustainable and cost-effective ERW type for a specific project.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878254","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}

{"title":"Analytical Modeling of Shrink-Fitted FGM Thick-Walled Cylinder","authors":"Samiha Zrinej, Noreddine Laghzale, Hakim A. Bouzid","doi":"10.4028/p-r5wvly","DOIUrl":"https://doi.org/10.4028/p-r5wvly","url":null,"abstract":"One off the most powerful assembly technique is the shrink-fitting process.It is found in many fields such us mechanics, petroleum, military industries as well as in nuclear power plants etc. This article developed an analytical formulation of shrink-fitted Functionally Graded Material axisymmetric thick-walled cylinder based on the linear plane elasticity theory. The stresses and displacement fields in the thick cylindrical shells are calculated using the laws of linear elasticity. The resulting displacements and stresses are analyzed, and particularly the residual contact pressure and her relationship with the interference values. The results show that the variation of the FGM material composition has a clear effect on the fit pressure in the intersection area of the two fitted cylinders. The value of this pressure affects the distribution of radial and tangential stresses in the FGM cylinder walls. Subsequently, we highlighted the influence of the interference value, on the residual contact pressure which increases with the increase of the interference value. The stresses are modeled for a case study using MATLAB software. keywords. shrink-fit, FGM, Interference, residual stress, Elasticity.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878942","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}

{"title":"Variability Analysis of Compressive and Flexural Performance of Coconut Fibre Reinforced Self-Compacting Concrete","authors":"Samson Olalekan Odeyemi, Michael Oluwasegun Adisa, Olumoyewa Dotun Atoyebi, Adeyemi Adesina, Ahmed Lukman, Adeniyi Olakiitan","doi":"10.4028/p-kcf6yl","DOIUrl":"https://doi.org/10.4028/p-kcf6yl","url":null,"abstract":"Self-compacting concrete (SCC) is a high-performance material that flows freely and consolidates without segregation or bleeding. This study investigated the effectiveness of incorporating coconut fiber into SCC to improve its strength and toughness. Three mixtures with coconut fiber inclusions of 0.2%, 0.4%, and 0.6% by weight of cement were used. The addition of coconut fiber reduced the workability and passing ability of the concrete, but all mixes met the SCC specification. The CFRSCC with 0.2% had the highest compressive and flexural strengths. The study concluded that adding 0.2% coconut fiber to SCC can increase its strength. The use of natural fibers like coconut can enhance the properties of concrete and could be an alternative to synthetic fibers, especially in regions where natural fibers are locally available and cost-effective.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135879294","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}

{"title":"International Journal of Engineering Research in Africa Vol. 66","authors":"A. O. Ibhadode","doi":"10.4028/b-epu4yq","DOIUrl":"https://doi.org/10.4028/b-epu4yq","url":null,"abstract":"","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139340609","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}

{"title":"Mathematical Modeling of Agricultural Insurance Pricing in Morocco","authors":"Yassine Kouach, Abderrahim El Attar, Mostafa El Hachloufi","doi":"10.4028/p-s5twyn","DOIUrl":"https://doi.org/10.4028/p-s5twyn","url":null,"abstract":"The world risks having an imbalance in terms of food security; this is why Morocco started the Moroccan Green Plan strategy in 2008 which aims to develop the agricultural sector. Agricultural insurance is considered among the levers of agricultural development. For this reason, the professionals must attach great importance to the pricing of agricultural insurance which allows the increase in the demand for this type of insurance and consequently the increase in agricultural investment. But, the existing approaches of pricing in agriculture insurance are limited to statistical modelling of the pure premium which consists of the estimation of the distribution assumptions of the yield. In this regard, this article aims to use a mathematical model in the pricing of agricultural insurance, with a view to offering a fair pure premium. The approach of this research seeks to build a powerful mathematical model taking into account the wheat yield growth stages and the weather conditions. The studied model will be used to price yield index insurance for wheat crops. The results showed that the mathematical model provided an adequate approximation of futures losses and the pure premiums expected. Furthermore, that model allows indemnifying the farmers in advance without waiting until the harvest time. This paper helps the insurers to establish an agriculture insurance price when the historical data are not enough to build a frequency-cost model.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878638","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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}