Pub Date : 2024-03-01DOI: 10.30941/CESTEMS.2024.00000
IN recent years, the electrical machines and systems have grown so rapidly with more and more applications in emerging civilian industries as well as cutting-edge areas. A group of novel and exciting technologies have been developed every year. First, the research of motors in new and extreme fields have constantly brought amazing progress to achieve better performance through new technologies such as digitalization, etc. Meanwhile, the fast development of power electronics in recent decades has also changed the overall system to be more flexible, and widely extent our boundary of research area. What is more, the advancing technologies such as information technology, new energy technology, artificial intelligence technology, etc., have shown their potential roles in this area, bringing more opportunities but more technique challenges as well. It was the best of times, it was the worst of times. At this point, we would like to share these most insightful ideas and progress to our peers. For this reason, CES TEMS promoted this new column Frontier.
{"title":"Message from Editors","authors":"","doi":"10.30941/CESTEMS.2024.00000","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00000","url":null,"abstract":"IN recent years, the electrical machines and systems have grown so rapidly with more and more applications in emerging civilian industries as well as cutting-edge areas. A group of novel and exciting technologies have been developed every year. First, the research of motors in new and extreme fields have constantly brought amazing progress to achieve better performance through new technologies such as digitalization, etc. Meanwhile, the fast development of power electronics in recent decades has also changed the overall system to be more flexible, and widely extent our boundary of research area. What is more, the advancing technologies such as information technology, new energy technology, artificial intelligence technology, etc., have shown their potential roles in this area, bringing more opportunities but more technique challenges as well. It was the best of times, it was the worst of times. At this point, we would like to share these most insightful ideas and progress to our peers. For this reason, CES TEMS promoted this new column Frontier.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10488441","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140342764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Here, we introduce a partitioned design method that is oriented toward airgap harmonic for permanent magnet vernier (PMV) motors. The method proposes the utilization of airgap flux harmonics as an effective bridge between the torque design region and the torque performances. To illustrate the efficacy of this method, a partitioned design PMV motor is presented and compared with the initial design. Firstly, the torque design region of the rotor is artfully divided into the torque enhancement region and ripple reduction region. Meanwhile, the main harmonics that generate output torque are chosen and enhanced, optimization. Moreover, the harmonics that generate torque ripple are selected and reduced based on torque harmonics optimization. Finally, the functions of the partitioned PMV motor torque are assessed based on the finite element method. By the purposeful design of these two regions, the output torque is strengthened while torque ripple is inhibited effectively, verifying the effectiveness and reasonability of the proposed design method.
{"title":"Airgap-Harmonic-Oriented Partitioned Design Method of PMV Motor with Improved Torque Performances","authors":"Zhaopeng Wu;Li Quan;Zixuan Xiang;Deyang Fan;Tengguang Wang;Xiaoyong Zhu","doi":"10.30941/CESTEMS.2024.00002","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00002","url":null,"abstract":"Here, we introduce a partitioned design method that is oriented toward airgap harmonic for permanent magnet vernier (PMV) motors. The method proposes the utilization of airgap flux harmonics as an effective bridge between the torque design region and the torque performances. To illustrate the efficacy of this method, a partitioned design PMV motor is presented and compared with the initial design. Firstly, the torque design region of the rotor is artfully divided into the torque enhancement region and ripple reduction region. Meanwhile, the main harmonics that generate output torque are chosen and enhanced, optimization. Moreover, the harmonics that generate torque ripple are selected and reduced based on torque harmonics optimization. Finally, the functions of the partitioned PMV motor torque are assessed based on the finite element method. By the purposeful design of these two regions, the output torque is strengthened while torque ripple is inhibited effectively, verifying the effectiveness and reasonability of the proposed design method.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 1","pages":"43-50"},"PeriodicalIF":0.0,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10452308","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140342765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator. Thus, this paper proposes a Gaussian Process Regression (GPR) model based on Conditional Likelihood Lower Bound Search (CLLBS) to optimize the design of the generator, which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method. Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example. Firstly, this method uses the elementary effect analysis to choose the sensitive variables, combining the evolutionary algorithm to design the super Latin cube sampling plan; Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data. A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established, which combined the chi-square test to optimize the accuracy of the model globally. Secondly, after the model reaches the accuracy, the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint. Last, the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation (CEI) optimization method based on the re-interpolation model, which cross-validated the optimization results of the Gaussian process regression model. The above method increase the efficiency of generator by 0.76% and 0.5% respectively; And this method can be used for rapid modeling and multi-objective optimization of generator systems.
{"title":"Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search","authors":"Xiao Liu;Pingting Lin;Fan Bu;Shaoling Zhuang;Shoudao Huang","doi":"10.30941/CESTEMS.2024.00001","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00001","url":null,"abstract":"The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator. Thus, this paper proposes a Gaussian Process Regression (GPR) model based on Conditional Likelihood Lower Bound Search (CLLBS) to optimize the design of the generator, which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method. Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example. Firstly, this method uses the elementary effect analysis to choose the sensitive variables, combining the evolutionary algorithm to design the super Latin cube sampling plan; Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data. A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established, which combined the chi-square test to optimize the accuracy of the model globally. Secondly, after the model reaches the accuracy, the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint. Last, the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation (CEI) optimization method based on the re-interpolation model, which cross-validated the optimization results of the Gaussian process regression model. The above method increase the efficiency of generator by 0.76% and 0.5% respectively; And this method can be used for rapid modeling and multi-objective optimization of generator systems.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 1","pages":"32-42"},"PeriodicalIF":0.0,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10452307","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140342669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-28DOI: 10.30941/CESTEMS.2023.00048
A. Infantraj;M. Augustine;E. Fantin Irudaya Raj;M. Appadurai
Permanent magnet brushless DC motors are used for various low-power applications, namely domestic fans, washing machines, mixer grinders and cooling fan applications. This paper focuses on selecting the best laminating material for the interior permanent magnet brushless DC (IPM BLDC) motor used in the cooling fan of automobiles. Various laminating materials, namely M19-29GA, M800-65A and M43, are tested using finite element analysis. The machine's vital performance metrics, namely the stator current, torque ripple, and hysteresis loss were analyzed in selecting the laminating material. The designed motor is also modelled as a mathematical model from the computed lumped parameters. The performance of the machines was validated through electromagnetic and thermal analysis.
{"title":"Investigation of Various Laminating Materials for Interior Permanent Magnet Brushless DC Motor for Cooling Fan Application","authors":"A. Infantraj;M. Augustine;E. Fantin Irudaya Raj;M. Appadurai","doi":"10.30941/CESTEMS.2023.00048","DOIUrl":"https://doi.org/10.30941/CESTEMS.2023.00048","url":null,"abstract":"Permanent magnet brushless DC motors are used for various low-power applications, namely domestic fans, washing machines, mixer grinders and cooling fan applications. This paper focuses on selecting the best laminating material for the interior permanent magnet brushless DC (IPM BLDC) motor used in the cooling fan of automobiles. Various laminating materials, namely M19-29GA, M800-65A and M43, are tested using finite element analysis. The machine's vital performance metrics, namely the stator current, torque ripple, and hysteresis loss were analyzed in selecting the laminating material. The designed motor is also modelled as a mathematical model from the computed lumped parameters. The performance of the machines was validated through electromagnetic and thermal analysis.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"7 4","pages":"422-429"},"PeriodicalIF":0.0,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10375946","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139060228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Content","authors":"","doi":"","DOIUrl":"https://doi.org/","url":null,"abstract":"","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"7 4","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10375945","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139060261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Content","authors":"","doi":"","DOIUrl":"https://doi.org/","url":null,"abstract":"","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"7 3","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/7873789/10272303/10272305.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68150014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.30941/CESTEMS.2023.00051
THE rapid growth of new energy vehicles is accelerating the low-carbon transition in the global transportation sector. According to the international energy agency report, more than 10 million electric vehicles (EVs) including pure electric and hybrid models were sold worldwide in 2022, which means that the global share of electric vehicles in the overall automotive market has risen from less than 5% in 2020 to 14% in 2022. Adoption of these 10 million EVs has reduced greenhouse emissions by a net amount of about 80 million tons. Along with rapid deployment of battery charging and swapping stations, it is expected for EVs to reduce oil demand by at least 5 million barrels per day and more CO2 emissions by EVs in 2030.
{"title":"Message from Editors","authors":"","doi":"10.30941/CESTEMS.2023.00051","DOIUrl":"https://doi.org/10.30941/CESTEMS.2023.00051","url":null,"abstract":"THE rapid growth of new energy vehicles is accelerating the low-carbon transition in the global transportation sector. According to the international energy agency report, more than 10 million electric vehicles (EVs) including pure electric and hybrid models were sold worldwide in 2022, which means that the global share of electric vehicles in the overall automotive market has risen from less than 5% in 2020 to 14% in 2022. Adoption of these 10 million EVs has reduced greenhouse emissions by a net amount of about 80 million tons. Along with rapid deployment of battery charging and swapping stations, it is expected for EVs to reduce oil demand by at least 5 million barrels per day and more CO2 emissions by EVs in 2030.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"7 3","pages":"237-238"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/7873789/10272303/10272306.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68150013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Axial-flux magnetic-geared machine (MGM) is a promising solution for electric vehicle applications for combining the virtues of both axial-flux electric machine and magnetic gear. However, generalized MGMs are limited by the torque density issue, accordingly inapplicable to industrial applications. To solve the abovementioned issue, an improved axial-flux magnetic-geared machine with a dual-winding design is proposed. The key merit of the proposed design is to achieve enhanced torque performance and space utilization with the proposed design, which installs a set of auxiliary winding between modulation rings. With the proposed design, overload protection capability, and fault-tolerant capability can be also achieved, for the proposed machine can work with either the excitation of armature windings or auxiliary windings. The pole-pair, slot combination, and parametric design is studied and optimized by the 3d finite-element method and designed C++ optimization software. Electromagnetic analysis and performance comparison indicate that the proposed machine can achieve a torque enhancement of 68.6% compared to the comparison machine.
{"title":"An Enhanced Axial-Flux Magnetic-Geared Machine with Dual-Winding Design for Electric Vehicle Applications","authors":"Weinong Fu;Qinying Wu;Shuangxia Niu;Yuanxi Chen;Xinhua Guo","doi":"10.30941/CESTEMS.2023.00047","DOIUrl":"https://doi.org/10.30941/CESTEMS.2023.00047","url":null,"abstract":"Axial-flux magnetic-geared machine (MGM) is a promising solution for electric vehicle applications for combining the virtues of both axial-flux electric machine and magnetic gear. However, generalized MGMs are limited by the torque density issue, accordingly inapplicable to industrial applications. To solve the abovementioned issue, an improved axial-flux magnetic-geared machine with a dual-winding design is proposed. The key merit of the proposed design is to achieve enhanced torque performance and space utilization with the proposed design, which installs a set of auxiliary winding between modulation rings. With the proposed design, overload protection capability, and fault-tolerant capability can be also achieved, for the proposed machine can work with either the excitation of armature windings or auxiliary windings. The pole-pair, slot combination, and parametric design is studied and optimized by the 3d finite-element method and designed C++ optimization software. Electromagnetic analysis and performance comparison indicate that the proposed machine can achieve a torque enhancement of 68.6% compared to the comparison machine.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"7 3","pages":"239-247"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/7873789/10272303/10272304.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68150012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.30941/CESTEMS.2023.00049
Yixuan Shuai;Dong Jiang;Zhuo Chen;Zicheng Liu;Haijing Sun;Peng Li
In traction application, speed range of motor is an important index for motor drives. In AC motor control, the maximum speed of the motor is limited by the output voltage capability of the traditional three-phase inverter with star connenction of windings. Switching the star connection to delta connection in high-speed range can extend the speed range. In order to extend the speed operation region, star-delta switch proposed by many literatures relies on mechanical relay, which needs a dead zone of tens of milliseconds and seriously affects torque output. Besides, the traditional method will cause current overshoot during the switch transient process, decreasing the device security and reliability. Aiming at the defects existing in the star-delta hard switching, this paper proposes a star-delta soft switching method. Without adding extra power electronics devices, DC-bus capacitor is used to provide the path of zero axis current in the transient process, which helps to achieve the smooth torque output and zero current switch in the transient. Experiments have been done to validate the performance of the proposed method. The switching transient from star to delta connection in the motor drive can be much more stable than hard switching method.
{"title":"Study of Star-Delta Soft Switch to Extend AC Motor High Speed Operation Region","authors":"Yixuan Shuai;Dong Jiang;Zhuo Chen;Zicheng Liu;Haijing Sun;Peng Li","doi":"10.30941/CESTEMS.2023.00049","DOIUrl":"https://doi.org/10.30941/CESTEMS.2023.00049","url":null,"abstract":"In traction application, speed range of motor is an important index for motor drives. In AC motor control, the maximum speed of the motor is limited by the output voltage capability of the traditional three-phase inverter with star connenction of windings. Switching the star connection to delta connection in high-speed range can extend the speed range. In order to extend the speed operation region, star-delta switch proposed by many literatures relies on mechanical relay, which needs a dead zone of tens of milliseconds and seriously affects torque output. Besides, the traditional method will cause current overshoot during the switch transient process, decreasing the device security and reliability. Aiming at the defects existing in the star-delta hard switching, this paper proposes a star-delta soft switching method. Without adding extra power electronics devices, DC-bus capacitor is used to provide the path of zero axis current in the transient process, which helps to achieve the smooth torque output and zero current switch in the transient. Experiments have been done to validate the performance of the proposed method. The switching transient from star to delta connection in the motor drive can be much more stable than hard switching method.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"7 3","pages":"248-255"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/7873789/10272303/10272328.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68150011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.30941/CESTEMS.2023.00050
Xiaobao Feng;Bo Wang;Chaohui Liu;Jiayun Zeng;Zheng Wang
Inter-turn fault is a serious stator winding short-circuit fault of permanent magnet synchronous machine (PMSM). Once it occurs, it produces a huge short-circuit current that poses a great risk to the safe operation of PMSM. Thus, an inter-turn short-circuit fault (ITSCF) diagnosis method based on high frequency (HF) voltage residual is proposed in this paper with proper HF signal injection. First, the analytical models of PMSM after the ITSCF are deduced. Based on the model, the voltage residual at low frequency (LF) and HF can be obtained. It is revealed that the HF voltage residual has a stronger ITSCF detection capability compared to the LF voltage residual. To obtain optimal fault signature, a 3-phase symmetrical HF voltage is injected into the machine drive system, and the HF voltage residuals are extracted. The fault indicator is defined as the standard deviation of the 3-phase HF voltage residuals. The effectiveness of the proposed ITSCF diagnosis method is verified by experiments on a triple 3-phase PMSM. It is worth noting that no extra hardware equipment is required to implement the proposed method.
{"title":"Research on Inter-Turn Short-Circuit Fault Diagnosis Method Based on High Frequency Voltage Residual for PMSM","authors":"Xiaobao Feng;Bo Wang;Chaohui Liu;Jiayun Zeng;Zheng Wang","doi":"10.30941/CESTEMS.2023.00050","DOIUrl":"https://doi.org/10.30941/CESTEMS.2023.00050","url":null,"abstract":"Inter-turn fault is a serious stator winding short-circuit fault of permanent magnet synchronous machine (PMSM). Once it occurs, it produces a huge short-circuit current that poses a great risk to the safe operation of PMSM. Thus, an inter-turn short-circuit fault (ITSCF) diagnosis method based on high frequency (HF) voltage residual is proposed in this paper with proper HF signal injection. First, the analytical models of PMSM after the ITSCF are deduced. Based on the model, the voltage residual at low frequency (LF) and HF can be obtained. It is revealed that the HF voltage residual has a stronger ITSCF detection capability compared to the LF voltage residual. To obtain optimal fault signature, a 3-phase symmetrical HF voltage is injected into the machine drive system, and the HF voltage residuals are extracted. The fault indicator is defined as the standard deviation of the 3-phase HF voltage residuals. The effectiveness of the proposed ITSCF diagnosis method is verified by experiments on a triple 3-phase PMSM. It is worth noting that no extra hardware equipment is required to implement the proposed method.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"7 3","pages":"256-265"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/7873789/10272303/10272327.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68150007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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