Pub Date : 2024-09-19DOI: 10.1109/TMAG.2024.3464113
Shingo Hiruma;Takeshi Mifune;Tetsuji Matsuo
This study discusses the estimation of the condition number of the quasi-static Darwin model, which is shown to be a nearly singular system of equations with a large kernel derived from the gauge invariance of full Maxwell’s equations. Inequality evaluations for a minimum nonzero singular value, maximum singular value, and condition number for a nearly singular system of equations and its augmented system are provided. This discussion reveals the nearly singular nature of the Darwin model and proves the effectiveness of the augmented system method for solving the Darwin model.
{"title":"Estimation of Condition Number of Quasi-Static Darwin Model","authors":"Shingo Hiruma;Takeshi Mifune;Tetsuji Matsuo","doi":"10.1109/TMAG.2024.3464113","DOIUrl":"https://doi.org/10.1109/TMAG.2024.3464113","url":null,"abstract":"This study discusses the estimation of the condition number of the quasi-static Darwin model, which is shown to be a nearly singular system of equations with a large kernel derived from the gauge invariance of full Maxwell’s equations. Inequality evaluations for a minimum nonzero singular value, maximum singular value, and condition number for a nearly singular system of equations and its augmented system are provided. This discussion reveals the nearly singular nature of the Darwin model and proves the effectiveness of the augmented system method for solving the Darwin model.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 12","pages":"1-4"},"PeriodicalIF":2.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article proposes a new method to calibrate the B–H properties measured by the vibrating sample magnetometer (VSM) for bar-shaped samples. It compensates for finite size and demagnetization effects using the neural networks (NNs) trained based on finite element analysis. Once the NNs are trained, they provide fast prediction of calibration results. The results from the proposed method are compared with those from the capacitive cancellation method, regarded as a reference due to its immunity to the effects of the demagnetizing field.
{"title":"Magnetic Property Calibration of Low-Permeability Materials for Vibrating Sample Magnetometers Using Neural Networks","authors":"Xiaohan Kong;Yuji Uehara;Naoya Terauchi;Natsuko Sato;Yoshibumi Matsuda;Masanori Nagano;Hajime Igarashi","doi":"10.1109/TMAG.2024.3463196","DOIUrl":"10.1109/TMAG.2024.3463196","url":null,"abstract":"This article proposes a new method to calibrate the B–H properties measured by the vibrating sample magnetometer (VSM) for bar-shaped samples. It compensates for finite size and demagnetization effects using the neural networks (NNs) trained based on finite element analysis. Once the NNs are trained, they provide fast prediction of calibration results. The results from the proposed method are compared with those from the capacitive cancellation method, regarded as a reference due to its immunity to the effects of the demagnetizing field.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 12","pages":"1-4"},"PeriodicalIF":2.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142267047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-18DOI: 10.1109/tmag.2024.3463471
Georg Lauhoff, Ranjan Sinha, Wayne Imaino
{"title":"Storage Infrastructure in the AI Era using Tape, HDD, and NAND Flash Memory","authors":"Georg Lauhoff, Ranjan Sinha, Wayne Imaino","doi":"10.1109/tmag.2024.3463471","DOIUrl":"https://doi.org/10.1109/tmag.2024.3463471","url":null,"abstract":"","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"7 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142267049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to accurately evaluate the deformation and noise caused by magnetostriction in the motor design stage, it is very important to accurately estimate the magnetostriction effect of electrical steel sheets (ESS). However, the magnetostrictive characteristics of the ESS are more sensitive to stress, and the uneven heat generated by the electrical equipment in the work will produce internal stress on the material, thus affecting the rotating magnetostrictive effect. Therefore, a test platform for magnetostrictive characteristics considering temperature gradient was built. The rationality of temperature gradient loading on the test platform was verified by simulation, and the magnetostrictive characteristics of non-oriented ESS under different temperature gradients were studied through the test platform. A magnetostrictive model is proposed, which takes into account the influence of temperature gradient on the magnetostrictive strain and the temperature gradient dependence of the principal strain characteristic of magnetostriction with the change of magnetic flux density. The results show that the temperature gradient will affect the magnetostrictive stability of the ESS and will have a certain effect on the magnetostrictive effect of the ESS, in which the effect is not obvious at low magnetic density but will have a greater effect at high magnetic density.
{"title":"Magnetostriction Model of Electrical Steel Sheets Considering Temperature Gradient","authors":"Zhen Wang;Zheming Fan;Yanli Zhang;Ziyan Ren;Dezhi Chen;Chang Seop Koh","doi":"10.1109/TMAG.2024.3462472","DOIUrl":"10.1109/TMAG.2024.3462472","url":null,"abstract":"In order to accurately evaluate the deformation and noise caused by magnetostriction in the motor design stage, it is very important to accurately estimate the magnetostriction effect of electrical steel sheets (ESS). However, the magnetostrictive characteristics of the ESS are more sensitive to stress, and the uneven heat generated by the electrical equipment in the work will produce internal stress on the material, thus affecting the rotating magnetostrictive effect. Therefore, a test platform for magnetostrictive characteristics considering temperature gradient was built. The rationality of temperature gradient loading on the test platform was verified by simulation, and the magnetostrictive characteristics of non-oriented ESS under different temperature gradients were studied through the test platform. A magnetostrictive model is proposed, which takes into account the influence of temperature gradient on the magnetostrictive strain and the temperature gradient dependence of the principal strain characteristic of magnetostriction with the change of magnetic flux density. The results show that the temperature gradient will affect the magnetostrictive stability of the ESS and will have a certain effect on the magnetostrictive effect of the ESS, in which the effect is not obvious at low magnetic density but will have a greater effect at high magnetic density.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 12","pages":"1-4"},"PeriodicalIF":2.1,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142267050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to model the magnetostrictive hysteresis behavior of grain-oriented electrical steel sheet (ESS) under the dc bias, a Jiles–Atherton (J–A) magnetostrictive model considering the effect of dc bias was constructed based on the J–A hysteresis model. First, according to the separation theory of loss, a dynamic J–A hysteresis model was established; then, considering the impact of dc bias and anisotropy, the expressions for effective magnetic field intensity and non-hysteretic magnetization strength were modified based on the free energy model; next, the improved J–A hysteresis model was combined with the model of secondary domain reversal considering the magnetostrictive hysteresis behavior to construct the J–A magnetostrictive model considering the effect of dc bias; finally, the particle swarm optimization (PSO) algorithm was used to extract parameters of the model combined with experimental data, and the model was verified for accuracy by comparing it with experimental data. It can model the magnetostriction of an oriented ESS plate in a complex working environment.
{"title":"Study of Magnetostrictive Characteristics Based on Dynamic J–A Model Under DC Bias","authors":"Zhen Wang;Runjie Yu;Yanli Zhang;Dezhi Chen;Ziyan Ren;Chang Seop Koh","doi":"10.1109/TMAG.2024.3462497","DOIUrl":"10.1109/TMAG.2024.3462497","url":null,"abstract":"In order to model the magnetostrictive hysteresis behavior of grain-oriented electrical steel sheet (ESS) under the dc bias, a Jiles–Atherton (J–A) magnetostrictive model considering the effect of dc bias was constructed based on the J–A hysteresis model. First, according to the separation theory of loss, a dynamic J–A hysteresis model was established; then, considering the impact of dc bias and anisotropy, the expressions for effective magnetic field intensity and non-hysteretic magnetization strength were modified based on the free energy model; next, the improved J–A hysteresis model was combined with the model of secondary domain reversal considering the magnetostrictive hysteresis behavior to construct the J–A magnetostrictive model considering the effect of dc bias; finally, the particle swarm optimization (PSO) algorithm was used to extract parameters of the model combined with experimental data, and the model was verified for accuracy by comparing it with experimental data. It can model the magnetostriction of an oriented ESS plate in a complex working environment.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 12","pages":"1-4"},"PeriodicalIF":2.1,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142267093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The forward model of eddy-current (EC) testing can predict the measurement signals, provided the known measurement conditions and physical properties of test pieces. In the analytical forward model, the test pieces are characterized by the reflection coefficient (RC), which describes the reflection characteristics of test pieces regarding incident electromagnetic (EM) waves and determines the phase of EC signals. The RC is calculated analytically with boundary conditions, which is sophisticated for analyzing complex geometries. In this study, the analytical model of plate and pipe testing using second-order vector potential (SOVP) is investigated. It is found that the numerical RC can be obtained from the source EM field in the air and counterparts in the presence of test pieces. In numerical simulations, the numerical RC is compared with the analytical RC for plate and pipe in a 2-D axisymmetric model. In the 3-D model, the calculated numerical RC corresponds to the dimensions of the measured plate and pipe with defects. In both 2-D and 3-D models, the phase of coil inductance from the numerical RC aligns with the finite-element solutions. It is validated that the RC is a characteristic of test pieces independent of the source field.
{"title":"Insight Into the Eddy-Current Reflection Coefficient of Plates and Pipes","authors":"Zihan Xia;Xue Bai;Ruochen Huang;Mingyang Lu;Wuliang Yin","doi":"10.1109/TMAG.2024.3462792","DOIUrl":"10.1109/TMAG.2024.3462792","url":null,"abstract":"The forward model of eddy-current (EC) testing can predict the measurement signals, provided the known measurement conditions and physical properties of test pieces. In the analytical forward model, the test pieces are characterized by the reflection coefficient (RC), which describes the reflection characteristics of test pieces regarding incident electromagnetic (EM) waves and determines the phase of EC signals. The RC is calculated analytically with boundary conditions, which is sophisticated for analyzing complex geometries. In this study, the analytical model of plate and pipe testing using second-order vector potential (SOVP) is investigated. It is found that the numerical RC can be obtained from the source EM field in the air and counterparts in the presence of test pieces. In numerical simulations, the numerical RC is compared with the analytical RC for plate and pipe in a 2-D axisymmetric model. In the 3-D model, the calculated numerical RC corresponds to the dimensions of the measured plate and pipe with defects. In both 2-D and 3-D models, the phase of coil inductance from the numerical RC aligns with the finite-element solutions. It is validated that the RC is a characteristic of test pieces independent of the source field.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 11","pages":"1-9"},"PeriodicalIF":2.1,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-16DOI: 10.1109/TMAG.2024.3461232
Reda Elkhadrawy;Joonas Vesa;Vasiliki Tsakaloudi;Paavo Rasilo
We propose a semi-analytical approach for modeling the macroscopic electromagnetic behavior of Mn–Zn ferrite cores under both dielectric and magnetic excitations. First, analytical material models are provided for calculating the effective parameters, i.e., complex resistivity and complex reluctivity by solving the electromagnetic fields in a single simplified grain and its boundary layer. The effective parameters are then used in 2-D axisymmetric finite-element (FE) models for solving the full-wave electromagnetic field equation in a cross section of a ferrite core under both dielectric and magnetic excitations. The simulated dielectric and magnetic impedances of a ferrite core are validated against measurements.
{"title":"Macroscopic Modeling of Mn–Zn Ferrites Based on Analytical Dynamic Material Models","authors":"Reda Elkhadrawy;Joonas Vesa;Vasiliki Tsakaloudi;Paavo Rasilo","doi":"10.1109/TMAG.2024.3461232","DOIUrl":"https://doi.org/10.1109/TMAG.2024.3461232","url":null,"abstract":"We propose a semi-analytical approach for modeling the macroscopic electromagnetic behavior of Mn–Zn ferrite cores under both dielectric and magnetic excitations. First, analytical material models are provided for calculating the effective parameters, i.e., complex resistivity and complex reluctivity by solving the electromagnetic fields in a single simplified grain and its boundary layer. The effective parameters are then used in 2-D axisymmetric finite-element (FE) models for solving the full-wave electromagnetic field equation in a cross section of a ferrite core under both dielectric and magnetic excitations. The simulated dielectric and magnetic impedances of a ferrite core are validated against measurements.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 12","pages":"1-4"},"PeriodicalIF":2.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10680555","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142736536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-16DOI: 10.1109/TMAG.2024.3461153
Zhaochen Li;Romain Corcolle
In this article, the effect of various localization rules in a ferroelectric multiscale model is studied. Ferroelectric materials are highly heterogeneous materials, which means local fields vary from grain to grain. Many localization rules can be used in multiscale models to consider for this heterogeneity. In this article, three localization rules are implemented, providing results, which are compared and analyzed. The results show that anisotropic localization should be preferred for more accurate predictions.
{"title":"Effect of Anisotropic Localization in a Ferroelectric Multiscale Model","authors":"Zhaochen Li;Romain Corcolle","doi":"10.1109/TMAG.2024.3461153","DOIUrl":"https://doi.org/10.1109/TMAG.2024.3461153","url":null,"abstract":"In this article, the effect of various localization rules in a ferroelectric multiscale model is studied. Ferroelectric materials are highly heterogeneous materials, which means local fields vary from grain to grain. Many localization rules can be used in multiscale models to consider for this heterogeneity. In this article, three localization rules are implemented, providing results, which are compared and analyzed. The results show that anisotropic localization should be preferred for more accurate predictions.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 12","pages":"1-4"},"PeriodicalIF":2.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-16DOI: 10.1109/TMAG.2024.3461470
Sina Khalesidoost;Sri Vignesh Sankarraman;Matthew C. Gardner
Knowledge of the rotor position is critical for the control of permanent magnet (PM) motors. Hall effect sensors (HESs) measure magnetic fields and provide a simple, inexpensive solution for determining rotor position. In existing systems, the HESs require the addition of PMs outside the motor, or the HESs are sensitive to the magnetic fields produced by the coil, in addition to the magnetic fields from the rotor PMs. However, quasi-Halbach arrays (QHAs), which are used in high-performance PM machines, produce a magnetic field orthogonal to the plane in which the PMs are magnetized. In this article, we investigate placing HESs to measure this orthogonal magnetic field for a simulated axial flux motor. In addition, we investigate this approach in simulation and experiment for a linear system. Both simulation and experimental results show that placing these HESs to measure the orthogonal magnetic fields generated by QHAs allows for the detection of the rotor position using the existing PMs in the machine and without being significantly affected by the magnetic field produced by the stator. In particular, the HESs should be placed orthogonally beyond the QHA and aligned with a stator slot to achieve the best performance. In both the simulated axial flux machine and the experimental linear system, positioning the HES in this manner yielded very good agreement between the flux density waveforms at no load and full load. In addition, the zero crossings of the flux density waveform, which are important for some control algorithms, were less than 1 electrical degree difference between no load and full load.
{"title":"Placement of Hall Effect Sensors in Permanent Magnet Motors Featuring Quasi-Halbach Array Configuration to Detect the Rotor Position Using Orthogonal Flux","authors":"Sina Khalesidoost;Sri Vignesh Sankarraman;Matthew C. Gardner","doi":"10.1109/TMAG.2024.3461470","DOIUrl":"https://doi.org/10.1109/TMAG.2024.3461470","url":null,"abstract":"Knowledge of the rotor position is critical for the control of permanent magnet (PM) motors. Hall effect sensors (HESs) measure magnetic fields and provide a simple, inexpensive solution for determining rotor position. In existing systems, the HESs require the addition of PMs outside the motor, or the HESs are sensitive to the magnetic fields produced by the coil, in addition to the magnetic fields from the rotor PMs. However, quasi-Halbach arrays (QHAs), which are used in high-performance PM machines, produce a magnetic field orthogonal to the plane in which the PMs are magnetized. In this article, we investigate placing HESs to measure this orthogonal magnetic field for a simulated axial flux motor. In addition, we investigate this approach in simulation and experiment for a linear system. Both simulation and experimental results show that placing these HESs to measure the orthogonal magnetic fields generated by QHAs allows for the detection of the rotor position using the existing PMs in the machine and without being significantly affected by the magnetic field produced by the stator. In particular, the HESs should be placed orthogonally beyond the QHA and aligned with a stator slot to achieve the best performance. In both the simulated axial flux machine and the experimental linear system, positioning the HES in this manner yielded very good agreement between the flux density waveforms at no load and full load. In addition, the zero crossings of the flux density waveform, which are important for some control algorithms, were less than 1 electrical degree difference between no load and full load.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 11","pages":"1-7"},"PeriodicalIF":2.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142518119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
High torque density permanent-magnet (PM) machines have become an increasingly critical requirement for drive systems. Traditional PM machines face significant challenges in achieving higher torque densities due to limitations imposed by electrical loading and heat dissipation conditions. In this article, a novel dual-sided consequent-pole flux-modulated PM machine (DCFPM) is proposed and compared. Both stator and rotor are adopted with consequent-pole PM arrangement to enhance modulation effect and improve torque density. Based on the air-gap field modulation theory, the topology, operating principle, and flux modulation effect of the proposed DCFPM are analyzed. The electromagnetic performances, including EMF, torque characteristics, PM utilization ratio, and power factor, are evaluated by finite element analysis. The results show that the bidirectional flux modulation in the proposed DCFPM is beneficial to enhancing flux densities and torque production capability. Finally, the discussions and conclusions about different PM machines are carried out; it can be concluded that the proposed machine with 12-slot/34-pole/12-modulation pole can offer merits of high torque density, high power factor, and excellent overload capability.
{"title":"Investigation of Dual-Sided Consequent-Pole Flux-Modulated Permanent-Magnet Machine by Air-Gap Field Modulation Theory","authors":"Shaoshuai Wang;Jianzhong Zhang;Ning Wang;Yongbin Wu","doi":"10.1109/TMAG.2024.3459048","DOIUrl":"10.1109/TMAG.2024.3459048","url":null,"abstract":"High torque density permanent-magnet (PM) machines have become an increasingly critical requirement for drive systems. Traditional PM machines face significant challenges in achieving higher torque densities due to limitations imposed by electrical loading and heat dissipation conditions. In this article, a novel dual-sided consequent-pole flux-modulated PM machine (DCFPM) is proposed and compared. Both stator and rotor are adopted with consequent-pole PM arrangement to enhance modulation effect and improve torque density. Based on the air-gap field modulation theory, the topology, operating principle, and flux modulation effect of the proposed DCFPM are analyzed. The electromagnetic performances, including EMF, torque characteristics, PM utilization ratio, and power factor, are evaluated by finite element analysis. The results show that the bidirectional flux modulation in the proposed DCFPM is beneficial to enhancing flux densities and torque production capability. Finally, the discussions and conclusions about different PM machines are carried out; it can be concluded that the proposed machine with 12-slot/34-pole/12-modulation pole can offer merits of high torque density, high power factor, and excellent overload capability.","PeriodicalId":13405,"journal":{"name":"IEEE Transactions on Magnetics","volume":"60 12","pages":"1-5"},"PeriodicalIF":2.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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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