Journal of Engineering and Applied Sciences最新文献_第6页

Taguchi Method for Design and Optimization of a High-Speed Permanent Magnet Synchronous Generator Protected by Retention Sleeve 高速永磁同步发电机保持套保护的田口法设计与优化

Journal of Engineering and Applied Sciences Pub Date : 2022-01-01 DOI: 10.11648/j.eas.20220702.12

H. Parivar, A. Darabi

引用次数: 1

A Proposed Mechanism of Hot-Cracking Formation During Welding Fan-Shaped Test Specimen Using Pulsed-Current Gas Tungsten Arc Welding Process 提出了一种脉冲电流钨气弧焊扇形试样焊接过程中热裂形成的机理

Journal of Engineering and Applied Sciences Pub Date : 2021-09-15 DOI: 10.11648/J.EAS.20210605.12

M. Abu‐Aesh, M. Taha, A. El-Sabbagh, L. Dorn

{"title":"A Proposed Mechanism of Hot-Cracking Formation During Welding Fan-Shaped Test Specimen Using Pulsed-Current Gas Tungsten Arc Welding Process","authors":"M. Abu‐Aesh, M. Taha, A. El-Sabbagh, L. Dorn","doi":"10.11648/J.EAS.20210605.12","DOIUrl":"https://doi.org/10.11648/J.EAS.20210605.12","url":null,"abstract":"Solidification cracking is a significant problem during the welding of fully austenitic stainless steels. The present work is considered as the first trial to investigate and propose a mechanism of hot cracking formation when welding the Fan-shaped cracking test specimen, using the pulsed current gas tungsten arc welding process (PCGTAW). The specimen lateral expansions perpendicular to welding line due to thermal effects, plus the transverse expansion due to crack opening are sensed and recorded to detect the crack behavior with time. The stages of crack formation are filmed by a high-speed photography of the weld pool and solidification process at a speed of about 1000 fps. Additionally, some microscopic examinations using Scanning Electron Microscope (SEM) and Electron Probe Micro-Analyzer (EPMA) are performed on the welds. The results helped in establishing a proposed mechanism for the formation of hot cracks in full–austenitic stainless steel welds done on a Fan-shaped test specimen. The proposed mechanism suggests three stages during hot cracking formation; the crack initiation, propagation, and ceasing. The occurrence of a hot crack during welding mainly depends on the way by which the molten zone solidifies, and which solid phase will primarily solidify. This affects, in turn, the segregation of the chemical elements, which found to have a great role in crack initiation. Moreover, the weld metal structure type, together with the thermal stresses in conjunction with the applied strains on the weld joint play a great role in the crack expansion and ceasing. The present work is considered the first trial done to propose a mechanism of hot-cracking formation during welding the Fan-Shaped test specimen using Pulsed-Current Gas Tungsten Arc welding process.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87400601","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: 1

Comparison of Chloride-Induced Corrosion of Microsilica and ECC in the Offshore Piers' Concrete (Case Study: Wharves P3 & P4 of Imam Khomeini Petrochemical) 海洋码头混凝土中微二氧化硅与ECC氯化物腐蚀的比较(以伊玛目霍梅尼石化P3、P4码头为例)

Journal of Engineering and Applied Sciences Pub Date : 2021-08-02 DOI: 10.11648/j.eas.20210604.11

A. Tangtakabi, M. H. Ramesht, A. G. Pahlaviani

{"title":"Comparison of Chloride-Induced Corrosion of Microsilica and ECC in the Offshore Piers' Concrete (Case Study: Wharves P3 & P4 of Imam Khomeini Petrochemical)","authors":"A. Tangtakabi, M. H. Ramesht, A. G. Pahlaviani","doi":"10.11648/j.eas.20210604.11","DOIUrl":"https://doi.org/10.11648/j.eas.20210604.11","url":null,"abstract":"The corrosion of reinforcements in the tidal zone leads to significant damage to offshore concrete piers. To overcome such damages, the quality of concrete and its mechanical properties should be improved. The aim of the present study is to identify and evaluate the causes and extent of corrosion observed in piers P3 & P4 in Imam Khomeini petrochemical. The concrete reinforced by microsilica and the ECC concrete are used to prevent corrosion. Some tests were conducted to determine the conditions of concrete piers in terms of reinforcement corrosion. Then, a reinforcement corrosion intensity test using Potentiostat involving a placement process was used, where the water-to-cement ratio was 38%; superplasticizers was 4%; and microsilica was 10% and 15%. The microsilica can serve as an alternative to the consumed cement and was measured according to the ASTM standards; Besides, it was exposed to aggressive conditions at different periods, and a concrete compressive strength test was performed. The results show that the compressive strength of concrete with microsilica 15% is nearly 25% higher than that of ECC, while for the control specimen, this value is about 42%. Regarding the corrosion intensity, the concrete with microsilica 15% has the minimum value compare to all three other samples. It is recommended to use this type of concrete to overcome the corrosion problem in piers P3 & P4 in Imam Khomeini petrochemical.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91210289","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

Mechanical Loading Model of Main Bearing of Wind Turbine Based on Test Bench 基于试验台的风力机主轴承力学载荷模型

Journal of Engineering and Applied Sciences Pub Date : 2021-07-08 DOI: 10.11648/J.EAS.20210603.13

Xing Yang, Tao Zhang, Lei Li, Ya-qian Wang

{"title":"Mechanical Loading Model of Main Bearing of Wind Turbine Based on Test Bench","authors":"Xing Yang, Tao Zhang, Lei Li, Ya-qian Wang","doi":"10.11648/J.EAS.20210603.13","DOIUrl":"https://doi.org/10.11648/J.EAS.20210603.13","url":null,"abstract":"Wind-turbine main bearing has to withstand dynamic loads with different directions and different magnitudes in complex environments, and its stable operation has a vital impact on the performance of the entire wind turbine. Therefore, the fatigue strength test of wind turbine bearing is helpful to ensure the normal operation of the whole wind turbine. According to the actual force of main bearing in natural environment, this paper designed a large-scale wind-turbine bearing test bench to detect the deformation performance of the bearing. Through the establishment of the mechanical loading model, the simulation of the actual working conditions of main bearing is realized by the loading of the eight hydraulic cylinders of the test bench, and the radial and axial displacement of the test bearing under different wind conditions are recorded by displacement sensors. A number of temperature sensors are used to monitor the real-time temperature change of the bearing inner ring. The test results show that the loading effect of eight hydraulic cylinders can realize the force of wind turbine bearing under wind load, and the test bench can effectively detect wind-turbine bearings with a diameter of 2.5 m. The mechanical loading method and test results can provide guidance for further inspection of the wind-turbine bearing.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85188088","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

Composition Series of the Solvable Multiplicative Abelian Groups over a Regular Even nth Roots of Unity: A Classical Approach 正则偶数n根上可解的乘法阿贝尔群的复合级数:一个经典的方法

Journal of Engineering and Applied Sciences Pub Date : 2021-06-29 DOI: 10.11648/J.EAS.20210603.12

Alechenu Benard, Babayo Muhammed Abdullahi, Daniel Eneojo Emmanuel

{"title":"Composition Series of the Solvable Multiplicative Abelian Groups over a Regular Even nth Roots of Unity: A Classical Approach","authors":"Alechenu Benard, Babayo Muhammed Abdullahi, Daniel Eneojo Emmanuel","doi":"10.11648/J.EAS.20210603.12","DOIUrl":"https://doi.org/10.11648/J.EAS.20210603.12","url":null,"abstract":"Solubility of algebraic structures is what gleaned the introduction of group theory, which later stems the other realms of abstract algebra viz: rings, fields and semigroup theories. The nth roots of unity is found in the most sensitive texts ever in the history of abstract algebra: Cauchy’s, Galois’ and Cayley’s. These three giant group theorists had the common ground of the roots of unity in even the title of their works. The idea is that if the nth roots of unity are solvable by radicals and so do the composition series approach, then all other products of the nth roots of unity - which the unity itself is part of - will automatically be solvable. Hence, all equations that dissolve to the least of the nth roots of unity are solvable by the composition series. This article penciled down how the congruence modulo of arithmetics due to Gauss and Leibnitz were used to break down the nth roots of unity, so that the recursive process can generate the composition series of normal subgroups between the unity and the group itself. Since they are P-Groups, they have normal P-Sylow Subgroups. The normality comes from the Index Theorem. Because they all have index 2 in their P-Groups, they are the maximal proper normal P-Sylow Subgroups and their factor groups are abelian accounting to the solubility of nth roots of unity by composition series. We combine the classical Euler Formula and the De Moivre Theorem to present the solvability of nth roots of unity. The P-Groups over nth roots of unity are multiplicative. nth roots of unity are subsequences of nth roots of unity and it converges to the limit point of the nth roots of unity.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"359 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77330505","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: 1

Effect of the Application of Aluminium Oxide on Recovery in Enhanced Oil Recovery 氧化铝在提高采收率中的应用效果

Journal of Engineering and Applied Sciences Pub Date : 2021-04-23 DOI: 10.11648/J.EAS.20210602.12

Odo Jude Emeka, Onyejekwe Ifeanyi, A. Chikwe, A. Nwachukwu, Okereke U. Ndubuisi, O. Ifeanyi, Obikaonu Agnes Chidiebere

{"title":"Effect of the Application of Aluminium Oxide on Recovery in Enhanced Oil Recovery","authors":"Odo Jude Emeka, Onyejekwe Ifeanyi, A. Chikwe, A. Nwachukwu, Okereke U. Ndubuisi, O. Ifeanyi, Obikaonu Agnes Chidiebere","doi":"10.11648/J.EAS.20210602.12","DOIUrl":"https://doi.org/10.11648/J.EAS.20210602.12","url":null,"abstract":"The use of metallic oxides in enhanced oil recovery in the initial stage seems to significantly enhance the productivity from a well by increasing the sweep efficiency, reduce interfacial tension, and reduce oil viscosity among other factors. However, in later stages of the life of the reservoir, it is observed that the technology brings adverse effects such as reduction in the permeability of the reservoir rock, which may cause decline in production and may lead to the abandonment of the reservoir, although there may be sufficient underlying hydrocarbon. This paper studies the extent of permeability alteration due to the aluminium oxide nano-powder, the total amount of recovery due to aluminium oxide nano-powder. It also compares the performance of aluminium oxide nano powder with other selected nano powders, which are silicon oxide and magnesium oxide. In the experiment, the Core Flooding System was used to simulate reservoir fluid flow in the constructed sand packs. The Enhanced Oil Recovery percentages as well as permeability changes were obtained. From the results, in comparison with traditional water flooding, aluminium oxide as well as silicon oxide and magnesium oxide gave high increase in recovery. However, aluminium produced the greatest recovery increase. A higher permeability change was given by aluminium oxide at higher concentration, while at lower concentration, aluminium oxide gave a lower permeability change.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78472361","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: 1

Research on Present Situation and the New Technology About Reinforcement in Collapsible Loess Foundation Inside Tunnels 隧道内湿陷性黄土地基加固现状及新技术研究

Journal of Engineering and Applied Sciences Pub Date : 2021-04-16 DOI: 10.11648/J.EAS.20210602.11

Zhao Yonghu, H. Kan, J. Yuhua, Mi Weijun, Xu Chunxiao, Wu Xiaopeng

{"title":"Research on Present Situation and the New Technology About Reinforcement in Collapsible Loess Foundation Inside Tunnels","authors":"Zhao Yonghu, H. Kan, J. Yuhua, Mi Weijun, Xu Chunxiao, Wu Xiaopeng","doi":"10.11648/J.EAS.20210602.11","DOIUrl":"https://doi.org/10.11648/J.EAS.20210602.11","url":null,"abstract":"The tunnel foundations treatment is the key and difficult point of the research of the tunnel in collapsible loess areas. The characteristics and advantages of the common foundations treatment technology for tunnels of loess areas are summarized in this paper, at the same time, the characteristics of a new technology for the non-vibration compaction treatment technology developed by the Northwest Research Institute Co., Ltd. of China Railway Engineering Corporation are introduced, which is suitable for the foundation reinforcement treatment of the tunnel in collapsible loess areas. Through the field experiment of base treatment of high-speed railway tunnel of the Baoji–Lanzhou High-Speed Railway Passenger Dedicated Line, it is demonstrated that the new non-vibration compaction machine has the advantages of convenient movement, controllable treatment effect, miniaturization, low cost and so on. The advancement and maneuverability are verified from the soil compaction coefficient between piles and the change law of collapsibility of the soil between piles under the different pile spacing conditions. The research results can provide new techniques and methods for the foundation reinforcement treatment of the tunnel of small space, strictly controlling construction vibration in collapsible loess areas.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74464990","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: 1

Teaching Reformation of Ideological and Political Theory Courses Using PAD Class Mode in Colleges and Universities 运用PAD课堂模式进行高校思想政治理论课教学改革

Journal of Engineering and Applied Sciences Pub Date : 2021-03-26 DOI: 10.11648/J.EAS.20210601.13

Chen Ruifeng

{"title":"Teaching Reformation of Ideological and Political Theory Courses Using PAD Class Mode in Colleges and Universities","authors":"Chen Ruifeng","doi":"10.11648/J.EAS.20210601.13","DOIUrl":"https://doi.org/10.11648/J.EAS.20210601.13","url":null,"abstract":"This article will explain what is PAD (Presentation, Assimilation, Discussion) Class and its ideological and political theory courses in colleges and universities, through the three-part class teaching process, transforms the generative dynamic and autonomous reconstruction in the mutual \"view\" of theory and practice, so that college students can stand on the basis of the Marxist crowd and use Marxist methodology builds Marxist theory on the practice of the unity of knowledge, affection, will, action, and belief, and integrates the practice of unity of knowledge, affection, intention, action, and belief into Marxist theory. PAD class divides the class teaching process into three non-invertible processes: teaching, internalization and absorption, and discussion. The teaching, internalized absorption and discussion of the sub-class are quite different from the corresponding elements in the previous class teaching process, and the teaching, internalized absorption and discussion of the sub-class are all element innovations. The purpose of this paper is to draw the conclusion that each element on the class teaching process is the innovation and the teaching process as a whole, such integration innovation, through the dynamic generative independent construction, ideological and political theory course to realize the ideological and political education from passive to active, making the Marxist stand, methodology of Marxism and Marxism theory in college students' knowledge, affection, will, action, and belief, and integrates the practice of unity of knowledge, affection, intention, action, and belief into Marxist theory, is a new kind of teaching mode for the future, is worth us further practice and popularization.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80830428","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: 1

A Fuzzy-Network Analysis Approach for Modeling and Analyzing Team Dependencies in Product Development Projects 产品开发项目中团队依赖关系建模与分析的模糊网络分析方法

Journal of Engineering and Applied Sciences Pub Date : 2021-03-17 DOI: 10.11648/J.EAS.20210601.12

Messa Alhammadi, Hamdi A. Bashir

{"title":"A Fuzzy-Network Analysis Approach for Modeling and Analyzing Team Dependencies in Product Development Projects","authors":"Messa Alhammadi, Hamdi A. Bashir","doi":"10.11648/J.EAS.20210601.12","DOIUrl":"https://doi.org/10.11648/J.EAS.20210601.12","url":null,"abstract":"Developing a complex product in a concurrent engineering environment requires managing information flow among ten or even hundreds of people of different specialties organized in a large number of product development (PD) teams. Managing these teams effectively requires understanding the level of information dependencies among them which are often vague and cannot be precisely predicted. Taking into account the limitations of relevant previous studies, this article proposes a fuzzy-social network analysis approach for modeling and analyzing the information flow among PD teams. The approach involves four major steps: mapping of dependencies, measuring the level of information dependencies based on the fuzzy set theory, visualizing the network, and performing quantitative analysis using three measures (network density, in-degree centrality, and out-degree centrality). To validate its practicality, the approach is used to model and analyze the dependencies among 22 PD teams in a real project adapted from the literature and involved developing an automobile engine. An advantage of the approach is that in addition to providing a holistic view of the interactions among PD teams, it permits PD project managers to identity the most important PD teams with respect to information flow control using a proposed new classification system that classifies PD teams under four categories: autonomous, receivers, transmitters, and transceivers.","PeriodicalId":15681,"journal":{"name":"Journal of Engineering and Applied Sciences","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87494068","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

Optimized TCP Congestion Control Over a Wired Network 有线网络中TCP拥塞控制的优化

Journal of Engineering and Applied Sciences Pub Date : 2021-01-01 DOI: 10.17582/journal.jeas/40.1.8.14

Jehan Dastagir, Muhammad Amir, B. Rehman, Shahid Hameed, M. Ashraf

引用次数: 0