Scientia Iranica最新文献_第3页

A Phenomenological Approach to Analysis of Maintenance Activities Impact on Interruption Duration in Electricity Distribution Systems, based on Historical Data and Expert Judgment 基于历史数据和专家判断的配电系统维修活动对中断时间影响分析的现象学方法

4区工程技术

Scientia Iranica Pub Date : 2023-10-10 DOI: 10.24200/sci.2023.62894.8090

Nima Salek Gilani, Alireza Fereidunian

{"title":"A Phenomenological Approach to Analysis of Maintenance Activities Impact on Interruption Duration in Electricity Distribution Systems, based on Historical Data and Expert Judgment","authors":"Nima Salek Gilani, Alireza Fereidunian","doi":"10.24200/sci.2023.62894.8090","DOIUrl":"https://doi.org/10.24200/sci.2023.62894.8090","url":null,"abstract":"This study intends to quantify, model and evaluate the impact of preventive maintenance (PM) on interruption duration (IntD) in electricity distribution systems, based on analyzing the data from the dashboard of an electricity distribution company and expert opinions. Following the data cleaning, the data are analyzed to identify the failure modes and their effects, to recognize the critical components (FMEA). Subsequently, the PM activities associated with them are investigated, to analyze the maintenance activities scheduling impact on IntD, employing expert judgment as a decision support. The data analysis reveals that the fuses and fuse holders experience the highest interruptions frequencies and durations, nominating them as critical components. Then, the impact of maintenance activity (inspection time) on the IntD percentage change is analyzed, leading to calculation of the sensitivity of IntD to maintenance activity. The quasi-linear shape of the IntD and ENS percentage decreases versus PM inspection time, i.e. the intended sensitivities is observed, thus two linear models are developed to represent this impact, suitable for maintenance optimization problems which need linear models convexity. Moreover, two indices of SIntDPM and SENSPM are introduced as maintenance KPIs representing the sensitivities, to prioritize PM actions versus their impact on IntD.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136360806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investments in energy efficiency with government environmental sensitiveness: An application of geometric programming and game theory 能源效率投资与政府环境敏感性:几何规划和博弈论的应用

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.60289.6706

Zahra Fatemi, Seyed Jafar Sadjadi, Armin Jabbarzadeh, Ahmad Makui

{"title":"Investments in energy efficiency with government environmental sensitiveness: An application of geometric programming and game theory","authors":"Zahra Fatemi, Seyed Jafar Sadjadi, Armin Jabbarzadeh, Ahmad Makui","doi":"10.24200/sci.2023.60289.6706","DOIUrl":"https://doi.org/10.24200/sci.2023.60289.6706","url":null,"abstract":"To maintain a competitive advantage, manufacturers of household appliances should promote the product’s energy efficiency, considering the impact on customer purchasing behavior. Since the product’s energy efficiency and pricing policies influence customers’ purchasing decisions, manufacturers confront significant challenges in balancing costs and demand since they must consider their profit-maximizing objective and government regulations. The Stackelberg game framework represents the interactions between the government, the leader, and a manufacturer, the follower, incorporating the government’s involvement in environmentally dependent social welfare under a tax structure. This paper proposes closed-form equilibrium using a game theory approach and geometric programming (GP) to solve the government’s and manufacturers’ non-linear decision models. The analytical results offer insight into the management’s approach to the product’s energy efficiency. The findings demonstrate that when clients’ concerns about energy-saving grow, the net payoff to the total manufacturer revenue ratio continuously decreases. The outcomes imply that the manufacturer must allocate significant revenue to tax expenditures in markets with more price-sensitive clients. As a motivation for research, this paper explores the application of the proposed model by examining a numerical example of a real-world refrigerator manufacturer case to obtain further managerial insight.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135149683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Investigation of the Heat Transfer and Peristaltic Flow Through a Asymmetric Channel Having Variable Viscosity and Electric Conductivity 具有变黏度和变电导率的非对称通道传热和蠕动流动的数值研究

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.60404.6783

Jamil Abbas Haider, Sana Gul, Sohail Nadeem

{"title":"Numerical Investigation of the Heat Transfer and Peristaltic Flow Through a Asymmetric Channel Having Variable Viscosity and Electric Conductivity","authors":"Jamil Abbas Haider, Sana Gul, Sohail Nadeem","doi":"10.24200/sci.2023.60404.6783","DOIUrl":"https://doi.org/10.24200/sci.2023.60404.6783","url":null,"abstract":"The peristaltic flow of nanofluids is a topic of growing interest in fluid dynamics. This study investigates the effect of temperature-dependent viscosity and electric conductivity on the peristaltic flow of nanofluids. The mathematical model of the peristaltic flow is developed using the governing equations of continuity, momentum, and energy for a Newtonian fluid. Large wavelength and small Reynolds number assumptions are used to study peristaltic flow to simplify the equations of continuity, momentum, and energy. In this article, the nanofluids are assumed to be electrically conducting and temperature dependent, and the effects of Hartman number and Eckert number is studied. The resulting equations are solved using the Shooting Method. The results show that the temperature-dependent viscosity and electric conductivity significantly affect the peristaltic flow of nanofluids. The flow rate and pressure gradient decrease with increasing viscosity and conductivity while the temperature and heat transfer rate increase. Moreover, the nanofluid concentration and particle size significantly impact the flow characteristics. In conclusion, this study comprehensively analyses the peristaltic flow of nanofluids with temperature-dependent viscosity and electric conductivity. The results can be useful for understanding the behaviour of nanofluids in various applications, such as drug delivery systems, microfluidics, and thermal management.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135149374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Computation insight of modified thermal distribution of hybrid nanofluids in complex wavy channel: A comparative thermal approach for different nanofluid models 复杂波浪形通道中混合纳米流体修正热分布的计算洞察:不同纳米流体模型的比较热方法

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.60957.7075

Imtiaz Ahmed, Shahid Hameed, Aamar Abbasi, Sami Ullah Khan, Waseh Farooq, Mohammed A. Almeshaal, Muapper Alhadri, Lioua Kolsi

{"title":"Computation insight of modified thermal distribution of hybrid nanofluids in complex wavy channel: A comparative thermal approach for different nanofluid models","authors":"Imtiaz Ahmed, Shahid Hameed, Aamar Abbasi, Sami Ullah Khan, Waseh Farooq, Mohammed A. Almeshaal, Muapper Alhadri, Lioua Kolsi","doi":"10.24200/sci.2023.60957.7075","DOIUrl":"https://doi.org/10.24200/sci.2023.60957.7075","url":null,"abstract":"Owing to enhanced thermal mechanism of nanomaterials, the researchers are continuously exploring the novel features of nanofluids and claiming multidisciplinary applications in solar systems, engineering processes, energy devices and automobile industries. The experimentally supported research proves that with interaction of different types of nanoparticles is more effective to enhance the thermal transportation phenomenon. Following such motivations in mind, the aim of present continuation is exploring the thermal impact of modified hybrid nanofluid model in complex vertical channel. Due to high thermal performances, copper (CuO), copper oxide (CuO) and aluminium oxide (Al_2 O_3) nanoparticles explore the thermal behavior of modified hybrid nanofluid model. The vertical channel confined the sinusoidal waves on walls. The flow phenomenon is based on peristaltic transport associated to the human body system. The consideration of small Reynolds number hypothesis and larger wavelength approach, the implication of problem has been done. The modeled equations are tackled with shooting technique. Various stream functions with applications of peristaltic transport phenomenon are developed. It is observed that heat transfer is larger in the curved channel as compared to the straight channel. The decomposition of modified hybrid nanoparticles is more effective to improve the heat transfer pattern more effectively.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135149695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A survey on data acquisition methods in conditional monitoring of wind turbines 风力发电机组状态监测数据采集方法综述

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.62909.8100

Reza Heibati, Ramin Alipour-Sarabi, Seyed Mohammad Taghi Bathaee

{"title":"A survey on data acquisition methods in conditional monitoring of wind turbines","authors":"Reza Heibati, Ramin Alipour-Sarabi, Seyed Mohammad Taghi Bathaee","doi":"10.24200/sci.2023.62909.8100","DOIUrl":"https://doi.org/10.24200/sci.2023.62909.8100","url":null,"abstract":"The generation of electrical power through wind turbines has significantly increased nowadays. However, these systems are prone to faults that can disrupt the network and incur substantial costs for the generation units. Therefore, effective maintenance scheduling becomes crucial. A major challenge faced by wind turbines is their maintenance requirements, as any interruption in their operation and power generation can result in significant economic losses. Consequently, meticulous planning is indispensable to minimize such consequences. This paper that is the first part of the study conducts a survey of data acquisition methods in condition monitoring of wind turbines. In the second part, signal processing techniques for condition monitoring of wind turbines are presented. Furthermore, the paper examines a range of studies that have implemented practical condition monitoring methods in wind turbines, delving into the associated challenges and proposing potential solutions. Various methods such as vibration analysis, acoustic analysis, electrical parameter analysis, AI-based techniques, and fault-tolerant control have been employed for wind turbine maintenance. However, limitations exist in terms of data availability and computational burden. Future challenges include developing algorithms that require less data, reducing computational requirements, updating models with new conditions, enabling early detection and proactive maintenance, and reducing maintenance costs.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135149552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cyclic and post-cyclic geocell pullout behavior in cohesionless soil 无黏性土的循环和后循环土工格室拉拔行为

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.60817.7002

Ali Namaei-kohal, Alireza Ardakani, Mahmoud Hassanlourad

{"title":"Cyclic and post-cyclic geocell pullout behavior in cohesionless soil","authors":"Ali Namaei-kohal, Alireza Ardakani, Mahmoud Hassanlourad","doi":"10.24200/sci.2023.60817.7002","DOIUrl":"https://doi.org/10.24200/sci.2023.60817.7002","url":null,"abstract":"As a geocell reinforced structure can be subjected to earthquake and pullout loads during its life time, it is obligatory to assess the pullout capacity and soil-geosynthetic interaction of geocell under cyclic loads. This research investigated the cyclic and post-cyclic pullout behavior of geocell in cohesionless soil using a series of 24 multi-stage pullout tests. The results indicated that the ultimate post-cyclic pullout load was less than the monotonic pullout load. This was the result of a reciprocating motion from loading caused by the interlock between the geocell infill soil and the surrounding material, which weakened and broke during the cyclic phase. It was found that, as the grain size of the soil increased, the interlocking strength increased and consequently the ultimate post cyclic pullout load increased. The soil particle size had a significant effect on the cumulative displacement during the cyclic phase. Furthermore, the increases in the loading amplitude and the number of cycles decreased the interlocking resistance of the infill soil with the surrounding material, which decreased the ultimate post-cyclic pullout load. The effect of the loading frequency likely depended on the geocell infill soil density.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135149545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Fault-Tolerant DC-DC Buck Converter with Zero Interruption Time for Autonomous Vehicles 自动驾驶汽车零中断容错DC-DC降压变换器

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.61387.7283

Preethi Sharma K., Vijayakumar T.

{"title":"A Fault-Tolerant DC-DC Buck Converter with Zero Interruption Time for Autonomous Vehicles","authors":"Preethi Sharma K., Vijayakumar T.","doi":"10.24200/sci.2023.61387.7283","DOIUrl":"https://doi.org/10.24200/sci.2023.61387.7283","url":null,"abstract":"A high-end autonomous vehicle is expected to have at least a hundred different electronic subsystems. Each one of them takes power from the battery through Power Management Unit (PMU). Having an efficient PMU is crucial and is expected to supply the required level of uninterrupted power. PMU consists of several buck converters which translate a higher voltage level to required lower voltage levels. A PMU is more reliable if it consists efficient and well-structured voltage converters. In this paper, a fault-tolerant buck converter is designed which outputs 3.3 volts. A simple yet effective technique is proposed to design a fault-tolerant buck DC-DC converter by bypassing the faulty converter leg. The proposed system utilizes a signal processing-based method for fault detection. The secondary converter is activated only upon the confirmed prognosis of a faulty primary converter. Ripple content in the output Aluminum Electrolytic Capacitor (AEC) voltage is monitored and used as a primary health indicator for the converter. An experimental setup is built and tested in the laboratory. Experimental results indicate a smooth transition from the primary converter to the secondary demonstrating an uninterrupted power supply along with the simplicity and effectiveness of the proposed solution.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135148980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Novel Algorithm to minimize PAPR of OFDM system with Less Intricacy PTS using Various Modulation Schemes 利用各种调制方式，减少复杂PTS的OFDM系统的最小PAPR算法

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.61419.7295

Deo Chandra Jaiswal, S. K. Sriwas, Abhishek Nigam, Siddharth Srivastava, Mahendra Kumar

引用次数: 0

Techno-economic analysis of a municipal wastewater treatment plant: A comparison among SBR, MLE & A2O Processes 某城市污水处理厂的技术经济分析:SBR、MLE和amp的比较A2O工艺

4区工程技术

Scientia Iranica Pub Date : 2023-10-09 DOI: 10.24200/sci.2023.61323.7250

Alireza Rabani mehr, Hasan Nikkhah, Mehrdad Farhadian

引用次数: 0

A New DC Offset Boostable Chaotic System with Multistability, Coexisting Attractors and Its Adaptive Synchronization 一种新的多稳定共存吸引子直流偏置可升压混沌系统及其自适应同步

4区工程技术

Scientia Iranica Pub Date : 2023-10-04 DOI: 10.24200/sci.2023.62359.7794

Rameshbabu Ramar, Sundarapandian Vaidyanathan

引用次数: 0