Journal of Engineering Research最新文献_第8页

Comparing time and cost performance of DBB and DB public construction projects in Kuwait 比较科威特 DBB 和 DB 公共建筑项目的时间和成本绩效

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.11.016

Sarah Soud Salem Al-enezi, Ruqaya Al Sabah

{"title":"Comparing time and cost performance of DBB and DB public construction projects in Kuwait","authors":"Sarah Soud Salem Al-enezi, Ruqaya Al Sabah","doi":"10.1016/j.jer.2023.11.016","DOIUrl":"10.1016/j.jer.2023.11.016","url":null,"abstract":"<div><div>Kuwait is an enormous construction site as many vital public projects are under construction or in preparatory stages to achieve the vision of a New Kuwait by 2035. However, the new Public Tenders Law No. 49 of 2016 authorized the sole operation of the Design-Bid-Build (DBB) method as the delivery system method, preventing the employment of Design-Build (DB). Hence, this research undertook a comparative analysis of cost and time performance of DBB and DB public construction projects in Kuwait for the first time, marking the originality of this study. Moreover, 160 projects were collected from four government entities. Then, the total collected projects were categorized based on contract types and project sizes depending on contract cost. This research has recognized that DB has superior performance compared to DBB regarding cost growth for all collected projects, both contract types, projects of less than 300,000 KD, and projects between 300,000 and 12 million KD. No statistically significant differences between DBB and DB projects regarding schedule growth were found for all collected projects, both contract types and project sizes. Furthermore, the findings indicated that the DBB projects’ construction intensity was faster than that of DB projects with a value between 300,00 KD and 12 million KD. For projects that had a value of more than 12 million KD, the DB projects’ construction intensity was faster than that of DBB projects. Hence, it is concluded that the issue is not with the DB delivery systems themselves, but rather with the deployment of these systems.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 4","pages":"Pages 680-690"},"PeriodicalIF":0.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139292549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance evaluation of turbulent circular heat exchanger with a novel flow deflector-type baffle plate 新型折流板型紊流循环换热器的性能评价

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.100105

Md Atiqur Rahman, Sushil Kumar Dhiman

引用次数: 0

Thermal image identification against pose and expression variations using deep learning 基于深度学习的姿态和表情变化的热图像识别

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.10.043

Naser Zaeri , Rusul Qasim

{"title":"Thermal image identification against pose and expression variations using deep learning","authors":"Naser Zaeri , Rusul Qasim","doi":"10.1016/j.jer.2023.10.043","DOIUrl":"10.1016/j.jer.2023.10.043","url":null,"abstract":"<div><div>Thermal infrared face recognition systems have developed as an effective complement to visual systems for biometric identity purposes and military operations. With the help of deep learning and convolutional neural networks, we provide an efficient approach for thermal facial identification that can handle position fluctuations and expression dissimilarities in this study. As an essential deep learning model that has demonstrated its effectiveness in several computer vision and machine learning applications, we employ the ResNet-50 architecture which consists of 50 layers of convolution, activation, and pooling. The structures of those layers are discussed in detail to gain a profound insight about the operation of this architecture. In this regard, a deep and detailed mathematical analysis is furnished. The system is implemented on a dataset of 1500 thermal images, where we execute experiments in various setups and circumstances to address the issues with posture and expression variance. The experimental results show that the system achieves an accuracy rate of 99.4% when it is trained using 30% of the dataset after five epochs. With respect to other performance measures, the system attains 100% recall, precision, F-score, and specificity. In comparison to recently published works, the findings show that the suggested system offers improved discriminability, resilience against fluctuations, as well as high identification rates under diverse settings that mimic real-world scenarios.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 4","pages":"Pages 751-760"},"PeriodicalIF":0.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135455323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An optimum design and economic feasibility analysis of wind farms in Kuwait using different wind generation technologies 科威特使用不同风力发电技术的风电场的优化设计和经济可行性分析

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.10.028

Rashad M. Kamel, Mohamed El Badawi, Sultan Sh. Alanzi

{"title":"An optimum design and economic feasibility analysis of wind farms in Kuwait using different wind generation technologies","authors":"Rashad M. Kamel, Mohamed El Badawi, Sultan Sh. Alanzi","doi":"10.1016/j.jer.2023.10.028","DOIUrl":"10.1016/j.jer.2023.10.028","url":null,"abstract":"<div><div>Kuwait plans to produce 15 % of its electricity from renewable resources by 2030. This paper aims at designing a 300-MW wind farm in six different sites in Kuwait. The study uses the measured wind data at Kuwait International Airport to predict the wind profile (speed and power density) at the selected sites. To validate the work, two different types of wind generation technologies are used in the design. The first type is Full-Converter Wind Turbine Generators (FCWTGs), and the second type is Doubly Fed Induction Generators (DFIGs). The designed wind farms are simulated using the Wind Atlas Analysis and Application Program (WAsP®) to estimate the Annual Energy Production (AEP) for each type of wind farms in each selected site. The location of every wind turbine in each wind farm (both types) for every selected site is accurately determined while considering needed spacing between rows and columns of turbines. The wake effect for downstream wind turbines is considered and estimated in the design. A comparison between the different wind farms in the six sites using the DIFGs and the FCWTGs generators is carried out. The economic feasibility of the designed wind farms is studied using the estimated Annual Energy Production (AEP) in each one of the designed wind farms.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 4","pages":"Pages 840-858"},"PeriodicalIF":0.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136009650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of an economic smart aquaponic system based on IoT 基于物联网的经济型智能水培系统开发

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.08.024

M.M.M. Mahmoud , Rania Darwish , A.M. Bassiuny

引用次数: 0

Efficacy of geopolymerization for integrated bagasse ash and quarry dust in comparison to fly ash as an admixture: A comparative study 与粉煤灰作为外加剂相比，综合蔗渣灰和石矿灰的土工聚合功效：比较研究

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-09-01 DOI: 10.1016/j.jer.2023.08.010

{"title":"Efficacy of geopolymerization for integrated bagasse ash and quarry dust in comparison to fly ash as an admixture: A comparative study","authors":"","doi":"10.1016/j.jer.2023.08.010","DOIUrl":"10.1016/j.jer.2023.08.010","url":null,"abstract":"<div><div>This study compares the efficacy of geopolymerized bagasse ash (GB) and geopolymerized quarry dust (GQ) with traditional flay ash-based geopolymer considering the strength properties of a subgrade. Geopolymerized composited binary admixture (GBA) was constituted by incorporating the optimum percentages of GQ and GB, on the basis of a maximum reduction of 70% and 52% in plasticity index value respectively. Then samples for strength tests such as unconfined compression tests and California bearing ratio tests were remolded using standard and modified compaction parameters. Also, the mineralogical and microstructural analyses were conducted based on SEM and EDS. The influence of curing and percentage of geopolymers was also investigated on strength properties. The performance of GBA is equivalent to traditional fly-ash-based geopolymer (GF) considering strength properties like <em>q</em><sub><em>u</em></sub> and CBR ensuring more than 200% increase in the strength at 20% and 15% content respectively. However, at these contents, the ductility of GBA-treated samples is 107% higher than GF making this geopolymer more suitable under dynamic load. Formation of geopolymer gel ((N, C)-A-S-H) is confirmed by microstructural and elemental analyses but the microstructure of GBA treated sample is more porous than the microstructure of GF treated sample, which provides some advantage for particles reorientation of GBA treated sample under load before failure. Also, the proposed multi-waste geopolymer has significant implications for waste management, as its implementation for the construction of a two-lane subgrade covering a distance of 1 kilometer may enable the repurposing of 1313 tons of assorted solid waste.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 3","pages":"Pages 328-339"},"PeriodicalIF":0.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75835229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of Morinda citrifolia extract as sustainable inhibitor for mild steel in saline environment 评估海巴戟提取物作为盐碱环境中低碳钢可持续抑制剂的作用

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-09-01 DOI: 10.1016/j.jer.2024.01.013

{"title":"Evaluation of Morinda citrifolia extract as sustainable inhibitor for mild steel in saline environment","authors":"","doi":"10.1016/j.jer.2024.01.013","DOIUrl":"10.1016/j.jer.2024.01.013","url":null,"abstract":"<div><div>In this study, the <em>Morinda citrifolia</em> extract was evaluated as a sustainable inhibitor of mild steel in saline environments. The work aimed to determine the inhibition efficiency of new active material for metal corrosion inhibition. The powdered simplicia of <em>M. citrifolia</em> was extracted in the macerator for three days using a solvent daily. The functional group bonds of this extract were analyzed by Fourier Transform Infrared (FT-IR). The performance of <em>M. citrifolia</em> extracts was evaluated with potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques using a three-electrode cell system. The surface morphology of mild steel was pictured by Field effect scanning electron microscopy (FE-SEM) coupled with energy dispersive X-ray spectroscopy (EDX). Potentiodynamic polarization results show decreasing corrosion current (I<sub>corr</sub>) with the presence of an extract of <em>M. citrifolia</em>. Furthermore, resistance capacity transfer (Rct) increases with the addition of <em>M. citrifolia</em> extract. The optimum inhibition efficiency (%IE) was achieved at 300 mg L<sup>−1</sup> concentrations with 85.10% efficiency by using the PDP technique. The mild steel morphology in the addition of <em>M. citrifolia</em> extracts is smoother than the surface without adding extracts. The increase in corrosion inhibition was associated with the molecule adsorption from the active compounds into the steel surface. The study results confirmed that <em>M. citrifolia</em> is a potential biomaterial engineering for corrosion inhibitors on mild steel in a saline environment.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 3","pages":"Pages 321-327"},"PeriodicalIF":0.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139637824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microstructure, mechanical and tribological properties of Al/Cu functionally graded material fabricated through powder metallurgy 通过粉末冶金制造的铝/铜功能分级材料的微观结构、机械和摩擦学特性

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-09-01 DOI: 10.1016/j.jer.2023.100119

引用次数: 0

Estimation of recompression coefficient of soil using a hybrid ANFIS-PSO machine learning model 利用 ANFIS-PSO 混合机器学习模型估算土壤的再压缩系数

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-09-01 DOI: 10.1016/j.jer.2023.10.018

{"title":"Estimation of recompression coefficient of soil using a hybrid ANFIS-PSO machine learning model","authors":"","doi":"10.1016/j.jer.2023.10.018","DOIUrl":"10.1016/j.jer.2023.10.018","url":null,"abstract":"<div><div>Recompression coefficient (Cr) is =an essential parameter utilized to predict consolidation settlement of over-consolidated soil. Thus, the main aim of this work was to estimate accurately the Cr, using a hybrid ANFIS-PSO Machine Learning (ML) model that is a hybridization of Adaptive Neuro-Fuzzy Inference System (ANFIS) and Particle Swarm Optimization (PSO). To compare the performance of proposed model, we selected two other benchmark ML models: single ANFIS and Support Vector Machines (SVM). We collected and utilized the data of304 soil samples tested from various construction projects in Vietnam, which included 12 input variables (soil parameters) and one output variable (Cr). Validation indices, namely Correlation Coefficient (R), Root Mean Square Error (RMSE), and Mean Absolute Error (MAE) were utilized for the validation of the model’s performance. Correlation analysis of feature selection results indicated that seven input variables namely clay content, plasticity index, liquidity index, degree of saturation, specific gravity, dry density, and bulk density were of importance and thus selected for prediction of the Cr. Validation results indicated that predictive capability of the hybrid ANFIS-PSO model (R = 0.802) is the best in comparison with other two benchmark models namely SVM (R = 0.727) and single ANFIS (R = 0.734). The findings of our study suggest that the ANFIS-PSO is a powerful ML tool for effectively and quickly prediction of the Cr of soil. This can help save time and reduce costs associated with laboratory experiments for determining this important geotechnical parameter.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 3","pages":"Pages 358-368"},"PeriodicalIF":0.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135922122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Direct flame test performance of boards containing waste undersized pumice materials 含有尺寸不足的废浮石材料的木板的直接火焰测试性能

IF 0.9 4区工程技术

Journal of Engineering Research Pub Date : 2024-09-01 DOI: 10.1016/j.jer.2023.09.007

{"title":"Direct flame test performance of boards containing waste undersized pumice materials","authors":"","doi":"10.1016/j.jer.2023.09.007","DOIUrl":"10.1016/j.jer.2023.09.007","url":null,"abstract":"<div><div>This study investigates the thermal performance of boards containing waste undersize pumice material directly exposed to flame in terms of thermal conductivity coefficient (TCC) and thermal efficiency ratio (TER). In the study, the direct flame was applied for 60 s on the front face of the 400×400×25 mm boards whose weight and density values, void ratio, porosity, and water absorption rates by weight and volume were determined. Because moisture content and porosity are significant factors in defining temperature-related properties of construction materials. The thermal characteristics of the boards were interpreted in this regard in connection to their moisture content and void ratios. At the end of the tests, the temperature difference between the front and back surfaces of the boards containing 10%, 30%, and 50% by weight of pumice stone powder and pumice sand was measured using a laser pyrometer. Compared to the reference sample without pumice, the TCC values decreased to 1.653, 1.649, and 1.540 W/mK, respectively, as a result of the use of pumice products in building materials. Moreover, TER values for the same samples increased to 82.6 %, 83.5 %, and 85.3 %, respectively.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 3","pages":"Pages 351-357"},"PeriodicalIF":0.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76403367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0