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Study on the Safety Thickness of Three Zones against Fault Water Inrush: Case Study and Model Development 三区防断层涌水安全厚度研究:案例研究与模型开发
IF 2.7
Journal of Engineering Pub Date : 2024-01-09 DOI: 10.1155/2024/8232145
Yongqian Wang, Benshui Yang, Jun Zhang
{"title":"Study on the Safety Thickness of Three Zones against Fault Water Inrush: Case Study and Model Development","authors":"Yongqian Wang, Benshui Yang, Jun Zhang","doi":"10.1155/2024/8232145","DOIUrl":"https://doi.org/10.1155/2024/8232145","url":null,"abstract":"The raising and flowing of groundwater caused by coal mining threaten the stability of mining faces, which cause casualties and machine damage accidents. Among the above accidents, the water inrush disaster caused by the water-rich water-conducting fault zone is the largest. Considering the complexity of geological structure and the suddenness of water inrush, reserving a reasonable thickness of waterproof coal pillars in front of the fault tectonic belt can effectively predict and control the occurrence of water inrush. The excellent adaptability of the numerical model to the geological conditions makes it an effective research method for simulating waterproof coal pillars. Based on the analysis of the background of on-site mining, this paper proposes a three-zone waterproof coal pillar calculation theory and establishes a numerical model for comparative analysis. The comparison results show that (1) the elastic-plastic theory and fracture theory can be used to calculate the thickness of the disturbed zone and the water-resisting zone, and the thickness of the fractured zone is positively correlated with the accuracy of the existing detection technology and equipment. (2) For the numerical model results, the increase of tangential stress is positively correlated with the distance of coal seam mining and the thickness of fault; the large plastic zone of the fault causes a higher increase in pore pressure, which ultimately increases the risk of water inrush. (3) The two results are in good agreement. The theoretical results have a safety margin, indicating that the three-zone theory is reasonable, which are used to guide the actual mining of the project to ensure the smooth passage of the project through the fault area.","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"37 13","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139442636","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
Design and Maintenance Optimisation of Substation Automation Systems: A Multiobjectivisation Approach Exploration 变电站自动化系统的设计与维护优化:多目标化方法探索
IF 2.7
Journal of Engineering Pub Date : 2024-01-06 DOI: 10.1155/2024/9390545
A. Cacereño, David Greiner, Andrés Zuñiga, B. Galván
{"title":"Design and Maintenance Optimisation of Substation Automation Systems: A Multiobjectivisation Approach Exploration","authors":"A. Cacereño, David Greiner, Andrés Zuñiga, B. Galván","doi":"10.1155/2024/9390545","DOIUrl":"https://doi.org/10.1155/2024/9390545","url":null,"abstract":"Substation automation systems (SAS) are critical infrastructures whose design and maintenance must be optimised to guarantee a suitable performance. In order to provide a collection of solutions that balance availability and cost, this paper explores the optimisation of the design and maintenance of a section of SAS. Multiobjective evolutionary algorithms are combined with discrete event simulation while the performance of two state-of-the-art multiobjective evolutionary algorithms is studied. On the one hand, the nondominated sorting genetic algorithm II (NSGA-II), and on the other hand, the S-metric selection evolutionary multiobjective optimisation algorithm (SMS-EMOA). Such a problem is solved from 2 and 3-objective approaches by attending to the multiobjectivisation concept. The robustness of the methodology is brought to light, and benefits were observed from the multiobjectivisation approach. Decision-makers can employ this knowledge to make informed decisions based on economic and reliability criteria.","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"5 5","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139380817","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
Effect of Source Type on Pore Structure and Properties of Aerated Geopolymer Concrete 源类型对加气土工聚合物混凝土孔隙结构和性能的影响
IF 2.7
Journal of Engineering Pub Date : 2024-01-02 DOI: 10.1155/2024/8634552
Luma D. Mohammed, Ameer A. Hilal, Ghada H. Alwan
{"title":"Effect of Source Type on Pore Structure and Properties of Aerated Geopolymer Concrete","authors":"Luma D. Mohammed, Ameer A. Hilal, Ghada H. Alwan","doi":"10.1155/2024/8634552","DOIUrl":"https://doi.org/10.1155/2024/8634552","url":null,"abstract":"A study has been carried out to produce environmentally friendly lightweight concrete by substituting cement with alternative geopolymer binders. Fly ash and silica fume (waste materials) were used as source materials and their effect on pore structure and properties of aerated geopolymer concrete was evaluated. Autoclaved aerated concrete, locally known as thermostone, was supplied from the market and tested as a reference mix. Three aerated geopolymer concrete mixes (around 550 kg/m3 density) were produced by mixing source materials (fly ash and silica fume), activator solution (sodium silicate and sodium hydroxide), and aeration agent (aluminum powder). It was found that by not only enhancing the pore structure but also improving the binder medium, the aerated geopolymer mixes were stronger and less absorbed than the autoclaved aerated concrete mix. However, the thermal insulation of the aerated concrete mix was better than those of aerated geopolymer concrete mixes. In terms of the source material, it was found that usage of fly ash helped in enhancing the strength by about 100% of autoclaved aerated concrete. In addition, unless its lowest density, aerated geopolymer mix made with fly ash and silica fume in combination absorbed less water than the other investigated mixes. Adding superplasticizer to the geopolymer mix helped in enhancing its pore structure by making the pores smaller, their irregularity lesser, and their number higher. In general, an environmentally friendly lightweight material with strength and absorption better than those of autoclaved aerated concrete was produced by adopting a geopolymerization process.","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"96 18","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139390285","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
Face-based Gender Classification Using Deep Learning Model 使用深度学习模型进行基于人脸的性别分类
IF 2.7
Journal of Engineering Pub Date : 2024-01-01 DOI: 10.31026/j.eng.2024.01.07
Buraq Abed Ruda Hassan, Faten Abd Ali Dawood
{"title":"Face-based Gender Classification Using Deep Learning Model","authors":"Buraq Abed Ruda Hassan, Faten Abd Ali Dawood","doi":"10.31026/j.eng.2024.01.07","DOIUrl":"https://doi.org/10.31026/j.eng.2024.01.07","url":null,"abstract":"Gender classification is a critical task in computer vision. This task holds substantial importance in various domains, including surveillance, marketing, and human-computer interaction. In this work, the face gender classification model proposed consists of three main phases: the first phase involves applying the Viola-Jones algorithm to detect facial images, which includes four steps: 1) Haar-like features, 2) Integral Image, 3) Adaboost Learning, and 4) Cascade Classifier. In the second phase, four pre-processing operations are employed, namely cropping, resizing, converting the image from(RGB) Color Space to (LAB) color space, and enhancing the images using (HE, CLAHE). The final phase involves utilizing Transfer learning, a powerful deep learning technique that can be effectively employed to Face gender classification using the Alex-Net architecture. The performance evaluation of the proposed gender classification model encompassed three datasets: the LFW dataset, which contained 1,200 facial images. The Faces94 dataset contained 400 facial images, and the family dataset had 400. The Transfer Learning with the Alex-Net model achieved an accuracy of 98.77% on the LFW dataset.\u0000Furthermore, the model attained an accuracy rate of 100% on both the Faces94 and family datasets. Thus, the proposed system emphasizes the significance of employing pre-processing techniques and transfer learning with the Alex-Net model. These methods contribute to more accurate results in gender classification. Where, the results achieved by applying image contrast enhancement techniques, such as HE and CLAHE, were compared. CLAHE achieved the best facial classification accuracy compared to HE.","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"12 10","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139395607","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 about the Effects of Blockage on Upstream Box Culverts 关于堵塞对上游箱形暗渠影响的实验研究
IF 2.7
Journal of Engineering Pub Date : 2024-01-01 DOI: 10.31026/j.eng.2024.01.09
Duaa Amir H. Al-kmoly, H. Q. Majeed
{"title":"Experimental Investigation about the Effects of Blockage on Upstream Box Culverts","authors":"Duaa Amir H. Al-kmoly, H. Q. Majeed","doi":"10.31026/j.eng.2024.01.09","DOIUrl":"https://doi.org/10.31026/j.eng.2024.01.09","url":null,"abstract":"This experimental study focuses on scouring in box culvert inlets under steady-state conditions and at different percentages of blockage ranging from 0% to 65%, and also looks at the hydraulics of water in the culvert. The investigation shows that the blockage of the culverts has influenced the scouring pattern at the blocked culverts' entrances. Ten experiments were carried out at the laboratory to see how blockage impacts the scouring pattern upstream of a box culvert during steady flow. Both partially blocked and unblocked cases were implemented in this study. The experimental tests were done until the equilibrium scour occurred, which took about 3.5 hours of water flow to reach equilibrium conditions.  The results revealed that the blockage will increase the water depth at the inlet by about 30%–50%, which may affect the safety of structures or cause culvert failure. In addition, the results discovered that the maximum scour depth, which inversely correlated with the obstruction upstream of the box culvert, increased with increasing discharge.\u0000 ","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"16 6","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139455317","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
Investigate IPD Factors' Effect on Value Engineering for the Communication Sector in Iraq 调查 IPD 因素对伊拉克通信行业价值工程的影响
IF 2.7
Journal of Engineering Pub Date : 2024-01-01 DOI: 10.31026/j.eng.2024.01.06
Prween S. Majeed, Mervit R. ALTaie
{"title":"Investigate IPD Factors' Effect on Value Engineering for the Communication Sector in Iraq","authors":"Prween S. Majeed, Mervit R. ALTaie","doi":"10.31026/j.eng.2024.01.06","DOIUrl":"https://doi.org/10.31026/j.eng.2024.01.06","url":null,"abstract":"Integrated project delivery is collaboratively applying the skills and knowledge of all participants to optimize the project's results, increase owner value, decrease waste, and maximize efficiency during the design, fabrication, and construction processes. This study aims to determine IPD criteria positively impacting value engineering. To do this, the study has considered 9 main criteria according to PMP classification that already covers all project phases and 183 sub-criteria obtained from theoretical study and expert interviews (fieldwork). In this study, the SPSS (V26) program was used to analyze the main criteria and sub-criteria priorities from top to bottom according to their values of the Relative Importance Index. The results of this study have clarified the) Project stockholders Management ( as the most significant main criteria with RII (74%) and (Stakeholders, work team, customers, suppliers, and project managers' support improve the probability of project implementation on the ground) as the most significant sub-criteria with (RII) (91%)","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"348 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139395113","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
Significant Safety Factors Affecting the Safety Performance in Iraqi Construction Projects 影响伊拉克建筑项目安全绩效的重要安全因素
IF 2.7
Journal of Engineering Pub Date : 2024-01-01 DOI: 10.31026/j.eng.2024.01.03
Qutaiba Qahtan Qaddoori, H. K. Breesam
{"title":"Significant Safety Factors Affecting the Safety Performance in Iraqi Construction Projects","authors":"Qutaiba Qahtan Qaddoori, H. K. Breesam","doi":"10.31026/j.eng.2024.01.03","DOIUrl":"https://doi.org/10.31026/j.eng.2024.01.03","url":null,"abstract":"Despite recent attempts to improve safety in the construction sector, this sector is considered dangerous and unsafe. Iraq is one of the emerging nations that suffers from a lack of construction safety management. In 2018, the construction sector in Iraq was responsible for 38% of all industrial accidents. Creating a safety program minimizes this problem by making safety an intrinsic part of construction projects. As a result, this article aims to identify the crucial safety factors that affect the safety performance in Iraqi construction projects. After conducting a critical literature review of the related literature, a list of 35 sub-factors classified into nine categories of main factors was chosen to rank each factor according to significance. A total of 100 sets of questionnaires were delivered to respondents in various construction projects. It was discovered that the \"Management Practices\" factor was considered the most key safety performance factor among all the main factors. The results also showed that among all the sub-factors, \"Personal protective equipment,\" \"First aid and medical care,\" and \"Contractor's site safety program\" were considered the most influential sub-factors. Furthermore, \"drug and alcohol tests for workers\" are the least important safety sub-factors. On the other hand, five sub-factors were excluded as being unimportant and not affecting safety performance.\u0000 ","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"31 12","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139455128","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
Improving Press Bending Production Quality through Finite Element Simulation: Integration CAD and CAE Approach 通过有限元模拟提高冲压弯曲生产质量:集成 CAD 和 CAE 方法
IF 2.7
Journal of Engineering Pub Date : 2024-01-01 DOI: 10.31026/j.eng.2024.01.02
Erico Sofyan Chrissandhi, Eko Pujiyanto, Tonny A. Yuniarto
{"title":"Improving Press Bending Production Quality through Finite Element Simulation: Integration CAD and CAE Approach","authors":"Erico Sofyan Chrissandhi, Eko Pujiyanto, Tonny A. Yuniarto","doi":"10.31026/j.eng.2024.01.02","DOIUrl":"https://doi.org/10.31026/j.eng.2024.01.02","url":null,"abstract":"Efficient operations and output of outstanding quality distinguish superior manufacturing sectors. The manufacturing process production of bending sheet metal is a form of fabrication in the industry of manufacture in which the plate is bent using punches and dies to the angle of the work design. Product quality is influenced by plate material selection, which includes thickness, type, dimensions, and material. Because no prior research has concentrated on this methodology, this research aims to determine V-bending capacity limits utilizing the press bending method. The inquiry employed finite element analysis (FEA), along with Solidworks was the tool of choice to develop drawings of design and simulations. The ASTM E290 standard guides this study. The software in this package may combine CAD (Computer-Aided Design) and CAE (Computer-Aided Engineering) without requiring extra design applications. This study tested SPCC and SPHC plate materials with five thickness variations. The findings embrace the number of failure risks associated with press bending exhibited on the von Mises stress diagram, which is directly proportional to showing the thickness limit of each material type throughout the bending process. The study's findings lay the groundwork for improving manufacturing quality by lowering the number of faulty goods produced by trial and error. Because the maximum allowable die width is 12 mm, the thickness limit of the press bending process is 2 mm. However, due to the greater intensity of the SPCC material, it has a reduced defect rate compared to SPHC material.","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"142 5","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139393815","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
Strengthening of GFRP Reinforced Concrete Slabs with Openings 带开口的 GFRP 钢筋混凝土板的加固
IF 2.7
Journal of Engineering Pub Date : 2024-01-01 DOI: 10.31026/j.eng.2024.01.10
Mohammed Abas Golham, A. H. A. Al-Ahmed
{"title":"Strengthening of GFRP Reinforced Concrete Slabs with Openings","authors":"Mohammed Abas Golham, A. H. A. Al-Ahmed","doi":"10.31026/j.eng.2024.01.10","DOIUrl":"https://doi.org/10.31026/j.eng.2024.01.10","url":null,"abstract":"Using fiber-reinforced polymer (FRP) could effectively improve the strength and endurance of reinforced concrete (RC) constructions. This study evaluated the flexural behavior of one-way concrete slabs with openings reinforced with glass fiber-reinforced polymers (GFRP) bars. It strengthened using carbon fiber-reinforced polymer (CFRP) sheets around the openings. The experimental program of this study is adopted by casting and testing four one-way concrete slabs with dimensions of (150*750*2650) mm. These slabs are divided into two groups based on whether they were strengthened or un-strengthened. For each group, two different openings (either one rectangular or two square) measured 250*500 mm and 250*250 mm, respectively, were fabricated within the pure flexural zone of the specimens. The experimental results indicate that using CFRP strips increases the maximum load capacity by around 29% for the slab with one rectangular opening and 21% for the slab with two square openings compared to the un-strengthened slabs. On the other hand, the deflection at a service load is decreased by about 35% and 37% for the slabs mentioned above, respectively.\u0000 ","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"157 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139395331","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
An Electronic and Web-Based Authentication, Identification, and Logging Management System 基于网络的电子认证、识别和日志管理系统
IF 2.7
Journal of Engineering Pub Date : 2024-01-01 DOI: 10.31026/j.eng.2024.01.01
A. Ibhaze, Onyekachukwu A. Aribeana
{"title":"An Electronic and Web-Based Authentication, Identification, and Logging Management System","authors":"A. Ibhaze, Onyekachukwu A. Aribeana","doi":"10.31026/j.eng.2024.01.01","DOIUrl":"https://doi.org/10.31026/j.eng.2024.01.01","url":null,"abstract":"The need for participants’ performance assessments in academia and industry has been a growing concern. It has attendance, among other metrics, is a key factor in engendering a holistic approach to decision-making. For institutions or organizations where managing people is an important yet challenging task, attendance tracking and management could be employed to improve this seemingly time-consuming process while keeping an accurate attendance record. The manual/quasi-analog approach of taking attendance in some institutions could be unreliable and inefficient, leading to inaccurate computation of attendance rates and data loss. This work, therefore, proposes a system that employs embedded technology and a biometric/ web-based application to enhance attendance management. The hardware encompasses the integration of an ESP8266 NodeMCU and the biometric AS608 fingerprint sensor interfaced with the database for which the front-end and back-end integration was through the React framework. The system uses a web application that displays the attendance results and scheduled course data from its database, provides feedback to lecturers on which student missed classes and calculates a student’s average attendance for the semester. By implementing this system, the accuracy of student attendance is expected to experience an appreciable improvement, eliminate proxy signing, provide a more secure alternative for attendance recording, curtail tardiness to classes, and ultimately improve student productivity on execution.","PeriodicalId":15716,"journal":{"name":"Journal of Engineering","volume":"104 S12","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139396011","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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