Scientia Iranica最新文献

Application of a novel quadratic polynomial discrete grey model to forecast energy consumption of China 一种新的二次多项式离散灰色模型在中国能源消费预测中的应用

4区工程技术

Scientia Iranica Pub Date : 2023-10-17 DOI: 10.24200/sci.2023.53774.3405

Xin Ma, Wenqing Wu, Yuanyuan Zhang

引用次数: 0

Temperature dependent heat generation and variable viscosity features for viscoelastic fluid with homogeneous and heterogeneous (HH) chemical reactions 具有均相和非均相(HH)化学反应的粘弹性流体的温度依赖性热生成和可变粘度特征

4区工程技术

Scientia Iranica Pub Date : 2023-10-17 DOI: 10.24200/sci.2023.61173.7179

Munazza Saeed, Bilal Ahmad, Chemseddine Maatki, Tasawar Abbas, Bilel Hadrich, Sami Ullah Khan, Karim Kriaa, Qazi Mehmood Ul-Hassan, Lioua Kolsi

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Modeling of Jet Electrochemical Machining Using Numerical and Design of Experiments Methods 射流电化学加工的数值模拟与实验设计方法

4区工程技术

Scientia Iranica Pub Date : 2023-10-17 DOI: 10.24200/sci.2023.60185.6650

Ali Mehrvar, Mohsen Motamedi, Abouzar Jamalpour

{"title":"Modeling of Jet Electrochemical Machining Using Numerical and Design of Experiments Methods","authors":"Ali Mehrvar, Mohsen Motamedi, Abouzar Jamalpour","doi":"10.24200/sci.2023.60185.6650","DOIUrl":"https://doi.org/10.24200/sci.2023.60185.6650","url":null,"abstract":"Modeling and determining the optimal conditions for the jet electrochemical machining (Jet-ECM) process is critical. In this study, a hybrid approach combining numerical and design of experiments (DOE) methods have been applied to model and determine the optimal conditions for Jet-ECM. The voltage (V), inner tool diameter (I), initial machining gap (G), and electrolyte conductivity (C) are considered input variables. Additionally, dimensional accuracy (E) and machining depth (D) are response variables. Twenty-seven numerical simulations have been performed using the Box–Behnken design to implement the response surface methodology (RSM). Consequently, two mathematical models have been obtained for these response variables. The effects of the input variables on the response variables are investigated using statistical techniques such as variance analysis. Furthermore, the desirability function approach has been applied to determine the optimal conditions for dimensional accuracy and depth of machining. The results show that the optimal values for achieving maximum depth of machining while maintaining a dimensional accuracy of 0.05 mm are as follows: electrolyte conductivity of 8 S/m, voltage of 36.9 V, initial machining gap of 200 μm, and inner tool diameter of 0.4 mm.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136078460","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}

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Improving the Performance of Variable Reluctance Resolver Against Short Circuit Using Physical Parameters 利用物理参数提高变磁阻变压器抗短路性能

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Scientia Iranica Pub Date : 2023-10-17 DOI: 10.24200/sci.2023.62539.7901

Hamed Lasjerdi, Zahra Nasiri-Gheidari

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An economic order quantity model for two deteriorating items with mutually complementary price and time dependent demand 价格互补且需求随时间变化的两种变质物品的经济订货量模型

4区工程技术

Scientia Iranica Pub Date : 2023-10-17 DOI: 10.24200/sci.2023.59611.6337

David Mahlangu, Olufemi Adetunji, Makoena Sebatjane

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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":"47 1","pages":"0"},"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":"78 1","pages":"0"},"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

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":"52 1","pages":"0"},"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":"15 1","pages":"0"},"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

Spline NLMS Adaptive Filter Algorithm based on the Signed Regressor of Input Signal 基于输入信号符号回归量的样条NLMS自适应滤波算法

4区工程技术

Scientia Iranica Pub Date : 2023-10-04 DOI: 10.24200/sci.2023.62258.7738

Hossein Tavakoli, Mohammad Shams Esfand Abadi

引用次数: 0