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Developing a 3D-FEM Model for Electromagnetic Analysis of an Axial Flux Permanent Magnet Machine

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Journal of Electromagnetic Analysis and Applications 2010年第4期2卷 258-263页

作者： Seyyed Mehdi Mirimani abolfazl vahedi 不详

Recently, many optimal designs for axial flux permanent magnet (AFPM) motors were performed based on finite- element (FE) analysis. Most of the models are based on reduction of 3D problem to 2D problem which is not accurate for design aspects. This paper describes an accurate electromagnetic analysis of a surface mounted, 28 pole AFPM with concentrated stator winding. The AFPM is modeled with three-dimensional finite-element method. This model in-cludes all geometrical and physical characteristics of the machine components. Using this accurate modeling makes it possible to obtain demanded signals for a very high precision analysis. Magnetic flux density, back-EMF, magnetic axial force and cogging torque of the motor are simulated using FLUX-3D V10.3.2. Meanwhile, the model is paramet-ric and can be used for design process and sensitivity analysis.

关键词： Axial Flux Permanent Magnet (AFPM) Motor Three-Dimensional Finite-Element Method (3D-FEM) Cogging Torque

Study on Axial Flux Hysteresis Motors Considering Airgap Variation

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Journal of Electromagnetic Analysis and Applications 2010年第4期2卷 252-257页

作者： Mohammad Modarres abolfazl vahedi Mohammadreza Ghazanchaei 不详

Axial flux hysteresis motor (AFHM) is self-starting synchronous motor that uses the hysteresis characteristics of magnetic materials. It is known that the magnetic characteristics of hysteresis motor could be easily affected by air gap and structure dimensions variation. Air gap length plays an important role in flux distribution in hysteresis ring and influences the output torque, terminal current, efficiency and even optimal value of other structural parameters of AFHM. Regarding this issue, in this study effect of air gap variation on performance characteristics of an axial flux hysteresis motor and effect of air gap length on hysteresis ring thickness and stator winding turns is investigated. Effect of air gap length on electrical circuit model is perused. Finally, simulation of AFHM in order to extract the output values of motor and sensitivity analysis on air gap variation is done using 3D-Finite Element Model. Hysteresis loop in the shape of an inclined ellipse is adopted. This study can help designers in design approach of such motors.

关键词： Hysteresis Loop Axial Flux Hysteresis Motor 3D-FEM Model Complex Permeability Air Gap Effect

Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： Mohammad Taghipoor abolfazl Hassani Mohammad M.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SFP was compared to HMA in terms of engineering characteristics and *** to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HMA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

Intelligent solubility estimation of gaseous hydrocarbons in ionic liquids

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Petroleum 2024年第1期10卷 109-123页

作者： Behnaz Basirat Fariborz Shaahmadi Seyed Sorosh Mirfasihi abolfazl Jomekian Bahamin Bazooyar Ahvaz Faculty of Petroleum Engineering Petroleum University of Technology (PUT) School of Engineering & Physical Sciences Heriot Watt University Department of Fluids & Environment The University of Manchester Department of Engineering Chemical Engineering Group Esfarayen University of Technology Mechanical and Aerospace Engineering Brunel University London

The research focuses on evaluating how well new solvents attract light hydrocarbons, such as propane,methane, and ethane, in natural gas sweetening units. It is important to accurately determine the solubility of hydrocarbons in these solvents to effectively manage the sweetening process. To address this challenge, the study proposes using advanced empirical models based on artificial intelligence techniques like Multi-Layer Artificial Neural Network(ML-ANN), Support Vector Machines(SVM), and Least Square Support Vector Machine(LSSVM). The parameters for the SVM and LSSVM models are estimated using optimization methods like Genetic Algorithm(GA), Particle Swarm Optimization(PSO), and Shuffled Complex Evolution(SCE). Data on the solubility of propane, methane, and ethane in various ionic liquids are collected from reliable literature sources to create a comprehensive database. The proposed artificial intelligence models show great accuracy in predicting hydrocarbon solubility in ionic liquids. Among these, the hybrid SVM models perform exceptionally well, with the PSO-SVM hybrid model being particularly efficient computationally. To ensure a comprehensive analysis, different examples of hydrocarbons and their order are included. Additionally, a comparative analysis is conducted to compare the AI models with the thermodynamic COSMO-RS model for solubility analysis. The results demonstrate the superiority of the AI models, as they outperform traditional thermodynamic models across a wide range of data. In conclusion, this study introduces advanced artificial intelligence algorithms such as ML-ANN, SVM, and LSSVM in accurately estimating the solubility of hydrocarbons in ionic liquids. The incorporation of optimization techniques and variations in hydrocarbon examples improves the accuracy, precision, and reliability of these intelligent models. These findings highlight the significant potential of AI-based approaches in solubility analysis and emphasize their superiori

关键词： Solubility Gaseous hydrocarbon Intelligent models Ionic liquids

Cancerous cell viability affected by synergism between electric pulses and a low dose of silver nanoparticle:An adaptive neuro-fuzzy inference system

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Medicine in Novel Technology and Devices 2024年第1期21卷 45-52页

作者： Salim Mirshahi Behzad vahedi Kiarash Aryana Ameneh Sazgarnia Department of Mechanical Engineering Sharif University of TechnologyTehranIran Medical Physics Research Center Mashhad University of Medical SciencesMashhadIran Functional Neurosurgery Research Center Shohada Tajrish Comprehensive Neurosurgical Center of ExcellenceShahid Beheshti University of Medical SciencesTehranIran Department of Mechanical Engineering Ferdowsi University of MashhadMashhadIran

In the current study,applying simultaneously electroporation and silver nanoparticles(SNPs)are ***,one restriction normally assigned to such nanoparticles is their side effects on the vital organs of the *** mitigate such deleterious effects,it is better to use lower dosages of ***,this can result in a decline in the technique's *** compensate for the lower dose of SNPs,one can use secondary method like electroporation to deliver SNPs directly into the cells and reinforces the effect of electric pulses due to the high electrical conductivity of SNPs while having a minimal cytotoxicity effect on normal cells that are not treated with *** the present study,synergism effects of both procedures(SNPs and electroporation)experimentally and theoretically are considered to investigate the property of each technique in increasing the performance with respect to both procedures'*** investigate more,adaptive neuro-fuzzy inference system(ANFIS)is used to predict the percent cell viability of cancerous cells affected by both procedures by considering amplitude and duration as inputs affecting on change of cell viability as an *** results obtained from both experimental and simulation procedures showed that the maximum synergism between nanoparticles and electric pulses was recorded at 700V/cm strength and 100μs ***,Results indicated high correlation between observed and predicted data(r2=0.88).Moreover,the calculated root mean square error for the results of the ANFIS model was equal to *** implies that the model has practical value and can estimate the percent cell viability of cancerous cells influenced by both procedures with varying electric field amplitude and *** method can be proposed for other biophysical or drug delivery applications to save time and resources by utilizing the previous experimental data rather than performing more experiments.

关键词： Electroporation Cancer cell Adaptive neuro-fuzzy inference system Nanoparticle Drug delivery

An Electrical Impedance Imaging System Towards Edge Intelligence for Non-Destructive Testing of Concrete

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Tsinghua Science and Technology 2024年第3期29卷 883-896页

作者： abolfazl Roshanpanah Mahdi Abbasi Hani Attar Ayman Amer Mohammad R.Khosravi Ahmed A.Solyman Department of Electrical Engineering Islamic Azad UniversityScience and Research BranceTehran ***Iran Department of Computer Engineering Bu-Ali Sina UniversityHamedan ***Iran Department of Energy Engineering Zarqa UniversityZarqa 13110Jordan Department of Computer Engineering Persian Gulf UniversityBushehr ***Iran Department of Electrical and Electronics Engineering Faculty of Engineering and ArchitectureNişantaşıUniversityIstanbul 34398Turkey

In the construction industry,to prevent accidents,non-destructive tests are necessary and *** impedance tomography is a new technology in non-invasive imaging in which the image of the inner part of conductive bodies is reconstructed by the arrays of external electrodes that are connected on the periphery of the *** equipment is cheap,fast,and edge *** this imaging method,the image of electrical conductivity distribution(or its opposite;electrical impedance)of the internal parts of the target object is *** image reconstruction process is performed by injecting a precise electric current to the peripheral boundaries of the object,measuring the peripheral voltages induced from it and processing the collected *** an electrical impedance tomography system,the voltages measured in the peripheral boundaries have a non-linear equation with the electrical conductivity *** paper presents a cheap Electrical Impedance Tomography(EIT)instrument for detecting impurities in the concrete.A voltage-controlled current source,a micro-controller,a set of multiplexers,a set of electrodes,and a personal computer constitute the structure of the *** conducted tests on concrete with impurities show that the designed EIT system can reveal impurities with a good accuracy in a reasonable time.

关键词： non-destructive testing system concrete electrical impedance tomography

Sino-nasal outcome Test-22 and Lund–Mackay CT score to select endoscopic sinus surgery in chronic rhinosinusitis

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第3期10卷 200-205页

作者： abolfazl Taheri Sajad Hasani Mohsen Saberi Esfeedvajani Masoumeh Saeedi Reyhane Abolghasemi New Hearing Technologies Research Center Clinical Sciences InstituteBaqiyatallah University of Medical SciencesTehranIran Department of Otorhinolaryngology Head and Neck SurgeryFaculty of MedicineBaqiyatallah University of Medical SciencesTehranIran Faculty of Medicine Baqiyatallah University of Medical SciencesTehranIran Department of Community Medicine MedicineQuran and Hadith Research CenterFaculty of MedicineBaqiyatallah University of Medical SciencesTehranIran

Objectives:Chronic rhinosinusitis is one of the common diseases that cause morbidity and affects a person's quality of *** tried to provide a more appropriate and effective approach to selecting patients for endoscopic sinus ***:The study population is chronic rhinosinusitis children referred to the ear,nose,and throat clinic of two general hospitals in Tehran,Iran,who have previously undergone sufficient drug treatment and have not *** Lund–Mackay score is calculated by examining the computed tomography(CT)*** Sino-nasal Outcome Test-22(SNOT-22)questionnaire was provided to the patients before the operation,after the operation,and 3 and 6 months later in the ***:Before the operation,the most SNOT-22 score people were in the range of 40–59 *** SNOT-22 score before the operation is significantly different from 3 and 6 months after the *** highest frequency of Lund–Mackay CT(LMCT)scan score was in the range of 18–23 *** LMCT scan score did not show any significant relationship with the SNOT-22 score before surgery,3 months,and 6 months after *** to aspirin had a significant relationship with SNOT-22 scores and the history of asthma and nasal polyps had a significant relationship with the preoperative LMCT scan ***:The LMCT scan scoring system cannot be a good measure of chronic rhinosinusitis severity or the prognosis of patients after *** SNOT-22 questionnaire can be used as a predictive tool to help the doctor and the patient in deciding to operate and the possibility of obtaining a relative recovery.

关键词： endoscopic surgical procedures Lund–Mackay CT score sinusitis SNOT-22 questionnaire

Best compromising crashworthiness design of automotive S-rail using TOPSIS and modified NSGAⅡ

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Journal of Central South University 2015年第1期22卷 121-133页

作者： abolfazl Khalkhali School of Automotive Engineering Iran University of Science and Technology

In order to reduce both the weight of vehicles and the damage of occupants in a crash event simultaneously, it is necessary to perform a multi-objective optimal design of the automotive energy absorbing components. Modified non-dominated sorting genetic algorithm II(NSGA II) was used for multi-objective optimization of automotive S-rail considering absorbed energy(E), peak crushing force(Fmax) and mass of the structure(W) as three conflicting objective functions. In the multi-objective optimization problem(MOP), E and Fmax are defined by polynomial models extracted using the software GEvo M based on train and test data obtained from numerical simulation of quasi-static crushing of the S-rail using ABAQUS. Finally, the nearest to ideal point(NIP)method and technique for ordering preferences by similarity to ideal solution(TOPSIS) method are used to find the some trade-off optimum design points from all non-dominated optimum design points represented by the Pareto fronts. Results represent that the optimum design point obtained from TOPSIS method exhibits better trade-off in comparison with that of optimum design point obtained from NIP method.

关键词： automotive S-rail crashworthiness technique for ordering preferences by similarity to ideal solution(TOPSIS) method group method of data handling(GMDH) algorithm multi-objective optimization modified non-dominated sorting genetic algorithm(NSGA II) Pareto front

Spin transfer torque in the semiconductor/ferromagnetic structure in the presence of Rashba effect

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Chinese Physics B 2017年第2期26卷 505-511页

作者： Javad vahedi Sahar Ghasab Satoory Department of Physics lslamic Azad University Sari Branch Sari Ira

Spin transfer torque in magnetic structure occurs when the transverse component of the spin current that flows from the nonmagnetic medium to ferromagnetic medium is absorbed by the interface. In this paper, considering the Rashba effect on the semiconductor region, we discuss the spin transfer torque in semiconductor/ferromagnetic structure and obtain the components of spin-current density for two models：（i） single electron and（ii） the distribution of electrons. We show that no matter whether the difference in Fermi surface between semiconductor and Fermi spheres for the up and down spins in ferromagnetic increases, the transmission probability decreases. The obtained results for the values used in this article illustrate that Rashba effect increases the difference in Fermi sphere between semiconductor and Fermi sphere for the up and down spins in ferromagnetic. The results also show that the Rashba effect, brings an additional contribution to the components of spin transfer torque, which does not exist in the absence of the Rashba interaction. Moreover, the Rashba term has also different effects on the transverse components of the spin torque transfer.

关键词： spin transfer torque Rashba interaction ferromagnetic