Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130301
Patrik Beňo, M. Kubiš, M. Gutten, Milan Šimko
Nowadays, there is a need to reduce emissions in the world and use electricity to drive vehicles. There is an increasing interest in small passenger vehicles suitable for crowded cities. In this paper we try to design a universal control structure for a single-wheeled vehicle with a tilt sensor. This structure can also be applied to a vehicle with parallel wheel arrangement. The paper describes a current and position loop suitable for a single wheeled vehicle. In the paper is designed a simple complementary filter for data processing from the accelerometer and gyroscope and a block diagram of the program for use in any microprocessor.
{"title":"Design of the steering structure for a single wheeled vehicle","authors":"Patrik Beňo, M. Kubiš, M. Gutten, Milan Šimko","doi":"10.1109/ELEKTRO49696.2020.9130301","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130301","url":null,"abstract":"Nowadays, there is a need to reduce emissions in the world and use electricity to drive vehicles. There is an increasing interest in small passenger vehicles suitable for crowded cities. In this paper we try to design a universal control structure for a single-wheeled vehicle with a tilt sensor. This structure can also be applied to a vehicle with parallel wheel arrangement. The paper describes a current and position loop suitable for a single wheeled vehicle. In the paper is designed a simple complementary filter for data processing from the accelerometer and gyroscope and a block diagram of the program for use in any microprocessor.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129752389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130303
V. V. Tregulov, V. Litvinov, A. Ermachikhin, A. D. Maslov
In this paper we investigated n+-p-junction silicon solar cells with antireflection por-Si film, formed on the front surface by anodic electrochemical etching. Photocurrent of the samples is measured. Also we used current deep level transient spectroscopy method. We found that defects with deep levels, appeared during formation of por-Si layer strongly affect photocurrent spectra of the cells due to the amplification of recombination of photogenerated charge carriers.
{"title":"Influence of deep level defects on photoelectrical processes in p-n junction solar cells with porous silicon antireflection coating","authors":"V. V. Tregulov, V. Litvinov, A. Ermachikhin, A. D. Maslov","doi":"10.1109/ELEKTRO49696.2020.9130303","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130303","url":null,"abstract":"In this paper we investigated n+-p-junction silicon solar cells with antireflection por-Si film, formed on the front surface by anodic electrochemical etching. Photocurrent of the samples is measured. Also we used current deep level transient spectroscopy method. We found that defects with deep levels, appeared during formation of por-Si layer strongly affect photocurrent spectra of the cells due to the amplification of recombination of photogenerated charge carriers.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121484628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130273
M. Cepenas, Bingzhong Peng, C. Ravikumar, V. Markevičius, N. Dubauskienė, A. Valinevicius, D. Navikas, M. Zilys, A. Merfeldas, D. Andriukaitis, N. Hinov
Piezoelectric energy harvesters have been extensively researched for use with wireless sensors or low power consumption electronic devices. Most of piezoelectric energy harvesters cannot generate enough power for potential applications. In this study, we explore parameters, including gap and proof mass, that can affect the damping of cantilever to optimize the design of energy harvester. A finite analysis is conducted using COMSOL Multiphysics software. In this type of simulation, loss factor is commonly used, but it produces a model that does not fit experimental data well. In order to build a true model, Rayleigh damping coefficients are measured to use in simulation. This resulted in a closer fit of modeling and experimental data, and a 5 times better output voltage from the optimized energy harvester comparing with using the smallest gap and mass.
{"title":"Research of Parameters of Plastic Piezoelectric Harvester for Practical Model Implementation","authors":"M. Cepenas, Bingzhong Peng, C. Ravikumar, V. Markevičius, N. Dubauskienė, A. Valinevicius, D. Navikas, M. Zilys, A. Merfeldas, D. Andriukaitis, N. Hinov","doi":"10.1109/ELEKTRO49696.2020.9130273","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130273","url":null,"abstract":"Piezoelectric energy harvesters have been extensively researched for use with wireless sensors or low power consumption electronic devices. Most of piezoelectric energy harvesters cannot generate enough power for potential applications. In this study, we explore parameters, including gap and proof mass, that can affect the damping of cantilever to optimize the design of energy harvester. A finite analysis is conducted using COMSOL Multiphysics software. In this type of simulation, loss factor is commonly used, but it produces a model that does not fit experimental data well. In order to build a true model, Rayleigh damping coefficients are measured to use in simulation. This resulted in a closer fit of modeling and experimental data, and a 5 times better output voltage from the optimized energy harvester comparing with using the smallest gap and mass.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124295676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130194
Jaroslav Bulava, L. Hargaš, D. Koniar, P. Sindler, Frantisek Jabloncík, Jozef Volák
The non-contact measurement by using the cameras has a high potential. The paper deals about possibilities to determine the kinematic parameters of rotating or periodically repeating actions using the stroboscopic effect. This phenomenon is recorded by a highspeed camera. Using the camera setup algorithm, the measured moving object can be optically slowed down, stopped or this object can move in the opposite direction. The whole measurement can be recorded as a snapshot. Kinematic parameters were measured on a phantom (DC motor) and the appropriate filter method was determined for results.
{"title":"Stroboscopic Measurement of Kinematic Parameters Using Highspeed camera","authors":"Jaroslav Bulava, L. Hargaš, D. Koniar, P. Sindler, Frantisek Jabloncík, Jozef Volák","doi":"10.1109/ELEKTRO49696.2020.9130194","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130194","url":null,"abstract":"The non-contact measurement by using the cameras has a high potential. The paper deals about possibilities to determine the kinematic parameters of rotating or periodically repeating actions using the stroboscopic effect. This phenomenon is recorded by a highspeed camera. Using the camera setup algorithm, the measured moving object can be optically slowed down, stopped or this object can move in the opposite direction. The whole measurement can be recorded as a snapshot. Kinematic parameters were measured on a phantom (DC motor) and the appropriate filter method was determined for results.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131032569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130270
I. V. Galitsyna, N. Yesenina
the article describes the main facts of implementing Content and Language Integrated Learning (CLIL) into the academic process of Ryazan State Radio Engineering University (RSREU). It presents teaching techniques applied in the course of learning both by the teachers of professional disciplines and the teachers of foreign language. Specific characteristics as well as main factors favoring the introduction of CLIL into the process of studying are presented, basic principles of applying CLIL in engineering universities are given.
{"title":"CLIL Technology in ICT-Based English Training of Engineering Students","authors":"I. V. Galitsyna, N. Yesenina","doi":"10.1109/ELEKTRO49696.2020.9130270","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130270","url":null,"abstract":"the article describes the main facts of implementing Content and Language Integrated Learning (CLIL) into the academic process of Ryazan State Radio Engineering University (RSREU). It presents teaching techniques applied in the course of learning both by the teachers of professional disciplines and the teachers of foreign language. Specific characteristics as well as main factors favoring the introduction of CLIL into the process of studying are presented, basic principles of applying CLIL in engineering universities are given.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131617151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130205
T. Horváth, P. Munster, Michal Látal, Ning-Hai Bao
Optical fibers allow more than high bandwidth for common services such as video and data transmission. The scientific community investigates optical fibers due to their delay value for photonic services, which require minimum conversions from the optical to the electrical domain. Optical fibers are used widely around the world, and with the decreasing price of optical components, it is possible to use optical fibers for infrastructure protection without any interruption of service. This article presents the measurement results for simultaneous transmission of two services with a sensor system according to the 100-GHz grid defined by the International Telecommunication Union. The results confirm that the 100-GHz grid is not sufficient.
{"title":"Photonic Services with Sensor System in One Fibre with 100-GHz DWDM Grid","authors":"T. Horváth, P. Munster, Michal Látal, Ning-Hai Bao","doi":"10.1109/ELEKTRO49696.2020.9130205","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130205","url":null,"abstract":"Optical fibers allow more than high bandwidth for common services such as video and data transmission. The scientific community investigates optical fibers due to their delay value for photonic services, which require minimum conversions from the optical to the electrical domain. Optical fibers are used widely around the world, and with the decreasing price of optical components, it is possible to use optical fibers for infrastructure protection without any interruption of service. This article presents the measurement results for simultaneous transmission of two services with a sensor system according to the 100-GHz grid defined by the International Telecommunication Union. The results confirm that the 100-GHz grid is not sufficient.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114460504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130249
G. Kácsor, M. Franko, J. Buday, Z. Biel, M. Hudák, Jaroslav Ilončiak
This paper presents the recent developed power supply concepts for feeding particle accelerator magnets. The developed concepts of power supplies are universal and modular platforms for current source power supplies, feeding magnets and superconducting magnets in particle accelerators. The developed concepts, based on MOSFET/IGBT technologies, are suitable for static and for dynamic mode operation particle accelerators like cyclotrons and synchrotrons. The dynamic mode types can recuperate energy from the superconducting magnets to the built-in storage capacitors or to the feeding network. This paper presents an overview, some design aspects, performances and test results of the developed power supply concepts at the EVPÚ company.
{"title":"Power Supply Concepts for Particle Accelerators","authors":"G. Kácsor, M. Franko, J. Buday, Z. Biel, M. Hudák, Jaroslav Ilončiak","doi":"10.1109/ELEKTRO49696.2020.9130249","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130249","url":null,"abstract":"This paper presents the recent developed power supply concepts for feeding particle accelerator magnets. The developed concepts of power supplies are universal and modular platforms for current source power supplies, feeding magnets and superconducting magnets in particle accelerators. The developed concepts, based on MOSFET/IGBT technologies, are suitable for static and for dynamic mode operation particle accelerators like cyclotrons and synchrotrons. The dynamic mode types can recuperate energy from the superconducting magnets to the built-in storage capacitors or to the feeding network. This paper presents an overview, some design aspects, performances and test results of the developed power supply concepts at the EVPÚ company.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115927313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130234
A. Allegra, G. Scelba, M. Cacciato, G. Scarcella, N. Salerno, S. Foti, A. Testa, D. Cavallaro, G. Bazzano, A. Cascio, G. Aiello
The main aim of this work is to provide a straightforward tool to modelize the thermal behavior of power module packages. The proposed circuit-based modeling approach takes into consideration the mutual thermal interaction among the dies, which plays a key role in the estimation of their working temperature. Furthermore, this modeling method features a compact and modular structure that can be easily tailored for different package configurations, maintaining limited complexity and computational burden. Last but not least, this thermal model includes both heating and cooling effects, thus allowing to evaluate thermal stresses even under pulse width modulated power devices. The thermal model is obtained starting from the temperature profiles carried out through a finite element analysis (FEA), by applying a power loss step to each single die. Starting from these profiles, a fitting curve algorithm is used to identify the elements of the RC networks used to represent the auto and mutual thermal impedances. The thermal model is thus an algebraic linear system including the RC networks parameters, and it can be exploited to identify the thermal status of each die of the power module even operating at different load conditions. The method has been applied in a SiC 3 phase inverter power module in which the high side and low side switches are formed with four parallel connected 1200V 350A SiC MOSFET dies. The results outgoing from the proposed model are confirmed by that carried out from FEA.
这项工作的主要目的是提供一个简单的工具来模拟电源模块封装的热行为。所提出的基于电路的建模方法考虑了模具之间的相互热作用，这对模具工作温度的估计起着关键作用。此外，该建模方法具有紧凑和模块化的结构，可以轻松地针对不同的封装配置进行定制，保持有限的复杂性和计算负担。最后但并非最不重要的是，该热模型包括加热和冷却效应，因此即使在脉宽调制功率器件下也可以评估热应力。热模型是从通过有限元分析(FEA)进行的温度分布开始，通过对每个单个模具应用功率损失步骤获得。从这些曲线开始，使用拟合曲线算法来识别用于表示自热阻抗和互热阻抗的RC网络元素。因此，热模型是一个包含RC网络参数的代数线性系统，并且可以利用它来识别功率模块的每个模具在不同负载条件下的热状态。该方法已应用于SiC三相逆变电源模块，其中高侧和低侧开关由四个并联的1200V 350A SiC MOSFET芯片组成。该模型的计算结果与有限元分析结果一致。
{"title":"Thermal Equivalent Circuit Model of Multi-Die SiC Power Modules","authors":"A. Allegra, G. Scelba, M. Cacciato, G. Scarcella, N. Salerno, S. Foti, A. Testa, D. Cavallaro, G. Bazzano, A. Cascio, G. Aiello","doi":"10.1109/ELEKTRO49696.2020.9130234","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130234","url":null,"abstract":"The main aim of this work is to provide a straightforward tool to modelize the thermal behavior of power module packages. The proposed circuit-based modeling approach takes into consideration the mutual thermal interaction among the dies, which plays a key role in the estimation of their working temperature. Furthermore, this modeling method features a compact and modular structure that can be easily tailored for different package configurations, maintaining limited complexity and computational burden. Last but not least, this thermal model includes both heating and cooling effects, thus allowing to evaluate thermal stresses even under pulse width modulated power devices. The thermal model is obtained starting from the temperature profiles carried out through a finite element analysis (FEA), by applying a power loss step to each single die. Starting from these profiles, a fitting curve algorithm is used to identify the elements of the RC networks used to represent the auto and mutual thermal impedances. The thermal model is thus an algebraic linear system including the RC networks parameters, and it can be exploited to identify the thermal status of each die of the power module even operating at different load conditions. The method has been applied in a SiC 3 phase inverter power module in which the high side and low side switches are formed with four parallel connected 1200V 350A SiC MOSFET dies. The results outgoing from the proposed model are confirmed by that carried out from FEA.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"128 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122893506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130125
Šimon Zoššák, Patrik Varecha, P. Makys
This paper deals with comparison of Field Oriented Control and Six-step control for high-speed PMSM drive. Common situation for these high-speed drives, but also large traction drives are high ratios of fundamental-to-sampling frequencies. In such case, the torque produced by these methods is greatly deteriorated and overall control quality is affected. Comparison of mentioned control algorithms in high-speed region is done based on ripple in electromagnetic torque.
{"title":"Comparison of Field Oriented and Six-step Control for High-speed PMSM Drive","authors":"Šimon Zoššák, Patrik Varecha, P. Makys","doi":"10.1109/ELEKTRO49696.2020.9130125","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130125","url":null,"abstract":"This paper deals with comparison of Field Oriented Control and Six-step control for high-speed PMSM drive. Common situation for these high-speed drives, but also large traction drives are high ratios of fundamental-to-sampling frequencies. In such case, the torque produced by these methods is greatly deteriorated and overall control quality is affected. Comparison of mentioned control algorithms in high-speed region is done based on ripple in electromagnetic torque.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129425087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-01DOI: 10.1109/ELEKTRO49696.2020.9130330
M. Kohan, V. Jakušová, J. Jakuš, J. Živčák, R. Hudák, M. Schnitzer, Mário Jančošek, Juliána Ivanková
Objective: Detection real absolute value of electric intensity (E) of electromagnetic field (EMF) generated from a mobile cell phone at 2G, 3G, 4G and local Wi-Fi networks for voice telephony and data transmission in the working environment. Methods: A total number of measurements was n= 225 in three different interior places. Measurements were realized by broadband sensor NARDA 550 at a frequency range of antenna 100 kHz - 3GHz. The time for one measurement was 6 min. The measured data were compared with the limit values of the Decree No. 534/2007 of Slovak Republic. Conclusion: The results showed that voice telephony in 3G network exhibited lower E of EMF than in 2G network. A comparison of data transmission showed that both 3G and 4G networks had a higher level of E EMF compared to the local Wi-Fi network. Limit values E EMF valid for the Slovak republic were not exceeded by any networking technology in all measured places.
{"title":"Comparison of networking technology in relationship with cellular phone radiation as a potential threat to the population","authors":"M. Kohan, V. Jakušová, J. Jakuš, J. Živčák, R. Hudák, M. Schnitzer, Mário Jančošek, Juliána Ivanková","doi":"10.1109/ELEKTRO49696.2020.9130330","DOIUrl":"https://doi.org/10.1109/ELEKTRO49696.2020.9130330","url":null,"abstract":"Objective: Detection real absolute value of electric intensity (E) of electromagnetic field (EMF) generated from a mobile cell phone at 2G, 3G, 4G and local Wi-Fi networks for voice telephony and data transmission in the working environment. Methods: A total number of measurements was n= 225 in three different interior places. Measurements were realized by broadband sensor NARDA 550 at a frequency range of antenna 100 kHz - 3GHz. The time for one measurement was 6 min. The measured data were compared with the limit values of the Decree No. 534/2007 of Slovak Republic. Conclusion: The results showed that voice telephony in 3G network exhibited lower E of EMF than in 2G network. A comparison of data transmission showed that both 3G and 4G networks had a higher level of E EMF compared to the local Wi-Fi network. Limit values E EMF valid for the Slovak republic were not exceeded by any networking technology in all measured places.","PeriodicalId":165069,"journal":{"name":"2020 ELEKTRO","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129726150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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