Pub Date : 2009-05-08DOI: 10.1109/ISPLC.2009.4913440
C. Konate, A. Kosonen, J. Ahola, M. Machmoum, J. Diouris
It is shown that an inverter-fed power line is a feasible medium for transmission of modulated information. This link is also a suitable alternative for the sensor cabling between motors and inverters in motor control and diagnostic applications. The use of the motor power cable in the speed feedback induction motor control application is presented in this paper.
{"title":"Induction motor speed control using power line communication","authors":"C. Konate, A. Kosonen, J. Ahola, M. Machmoum, J. Diouris","doi":"10.1109/ISPLC.2009.4913440","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913440","url":null,"abstract":"It is shown that an inverter-fed power line is a feasible medium for transmission of modulated information. This link is also a suitable alternative for the sensor cabling between motors and inverters in motor control and diagnostic applications. The use of the motor power cable in the speed feedback induction motor control application is presented in this paper.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133535628","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913423
J. S. Lee, Hui-Myoung Oh, Ji-Tae Kim, Jin Young Kim
Orthogonal frequency division multiplexing (OFDM) modulation using orthogonal subcarriers reduces the delay spread by increasing robustness to multipath fading and can use overlapped bandwidth due to orthogonality on frequency domain. Thus, OFDM has been adopted for high speed data transmission of multimedia traffic such as HomePlug A/V and Mobile WiMax. However, OFDM also has a drawback of a high PAPR (peak-to-average-power-ratio). This high PAPR takes place due to parallel processing of a number of data at once using a fast Fourier transform (FFT) processor. Due to this high PAPR amplifier usually does not act in dynamic range. In this paper, we propose an algorithm that can reduce PAPR using selective mapping (SLM) in power line communication (PLC) channel. In order to utilize SLM technique, side information needs to be transmitted for demodulation while degrading transmission efficiency. We propose and analyze scaled SLM technique which removes necessity of the side information.
{"title":"Performance of scaled SLM for PAPR reduction of OFDM signal in PLC channels","authors":"J. S. Lee, Hui-Myoung Oh, Ji-Tae Kim, Jin Young Kim","doi":"10.1109/ISPLC.2009.4913423","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913423","url":null,"abstract":"Orthogonal frequency division multiplexing (OFDM) modulation using orthogonal subcarriers reduces the delay spread by increasing robustness to multipath fading and can use overlapped bandwidth due to orthogonality on frequency domain. Thus, OFDM has been adopted for high speed data transmission of multimedia traffic such as HomePlug A/V and Mobile WiMax. However, OFDM also has a drawback of a high PAPR (peak-to-average-power-ratio). This high PAPR takes place due to parallel processing of a number of data at once using a fast Fourier transform (FFT) processor. Due to this high PAPR amplifier usually does not act in dynamic range. In this paper, we propose an algorithm that can reduce PAPR using selective mapping (SLM) in power line communication (PLC) channel. In order to utilize SLM technique, side information needs to be transmitted for demodulation while degrading transmission efficiency. We propose and analyze scaled SLM technique which removes necessity of the side information.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127845710","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913409
Jimyung Kang, Yonghwa Kim, Kwanho Kim
In this paper, we show the hidden terminal problem of Korea Standard protocol in the PLC access network. PLC access network has serious hidden terminal problem at the master nodes because of its topology characteristic. We propose simple strategies to improve performance. The proposed strategies can make network operate in acceptable throughput range when original KS provides near-zero throughput.
{"title":"Hidden terminal of Korea Standard PLC protocol in access network","authors":"Jimyung Kang, Yonghwa Kim, Kwanho Kim","doi":"10.1109/ISPLC.2009.4913409","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913409","url":null,"abstract":"In this paper, we show the hidden terminal problem of Korea Standard protocol in the PLC access network. PLC access network has serious hidden terminal problem at the master nodes because of its topology characteristic. We propose simple strategies to improve performance. The proposed strategies can make network operate in acceptable throughput range when original KS provides near-zero throughput.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114789722","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913415
S. Hosoya, M. Tokuda, T. Mastuo
In this paper, we paid to attention for the switchboard actually used at house, and evaluated the transmission loss characteristic of the power line transmission model with the switchboard, and its influence to the transmission speed of OFDM signal. First, in case of power line transmission model without the circuit line, it was confirmed that the transmission loss characteristics inside a circuit breaker and through a main breaker are almost the same characteristics, but the transmission loss in the in-phase is smaller by about 10dB than that in the out-of-phase. PHY rate of in-phase transmission is full PHY rate of about 185Mbps, but PHY rate of out-of-phase transmission decreases to 150Mbps. Next, in case of power line transmission model with the branch line, the transmission loss characteristic in the in-phase and the out-of-phase transmissions had sharp attenuation of about 20dB at the frequency of around 4MHz, because of the signal resonance in the branch line (10m length). However, this sharp attenuation did not affect to PHY rate in the in-phase transmission, if anything, in the out-of-phase transmission, PHY rate was improved by the branch line. Finally, PHY rate of PLC modem was calculated by MATLAB/ Simulink, and compared with measurement value. It was understood that the calculation value almost agreed with the measurement one in the in-phase transmission.
{"title":"OFDM signal transmission characteristics through a switchboard for a power line communication","authors":"S. Hosoya, M. Tokuda, T. Mastuo","doi":"10.1109/ISPLC.2009.4913415","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913415","url":null,"abstract":"In this paper, we paid to attention for the switchboard actually used at house, and evaluated the transmission loss characteristic of the power line transmission model with the switchboard, and its influence to the transmission speed of OFDM signal. First, in case of power line transmission model without the circuit line, it was confirmed that the transmission loss characteristics inside a circuit breaker and through a main breaker are almost the same characteristics, but the transmission loss in the in-phase is smaller by about 10dB than that in the out-of-phase. PHY rate of in-phase transmission is full PHY rate of about 185Mbps, but PHY rate of out-of-phase transmission decreases to 150Mbps. Next, in case of power line transmission model with the branch line, the transmission loss characteristic in the in-phase and the out-of-phase transmissions had sharp attenuation of about 20dB at the frequency of around 4MHz, because of the signal resonance in the branch line (10m length). However, this sharp attenuation did not affect to PHY rate in the in-phase transmission, if anything, in the out-of-phase transmission, PHY rate was improved by the branch line. Finally, PHY rate of PLC modem was calculated by MATLAB/ Simulink, and compared with measurement value. It was understood that the calculation value almost agreed with the measurement one in the in-phase transmission.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116244050","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913443
Qingyang Liu, Bingzhen Zhao, Yirong Wang, Jing Hu
With the energy reduction become more and more popular, power company need to build AMR system to improve energy efficiency. Many AMR systems around the world have used PLC as communication channel and it's the same in China. BPL technology has become more mature, and it's reliability, stability and practicality has been verified in a number of field trial which shows great potential in the future market. This paper introduces the status of AMR in China at first, and shows two typical application cases of AMR system based on BPL, and also describes the perspective of this solution. The use of BPL technology in AMR system laid the foundation of smart grid in the future.
{"title":"Experience of AMR systems based on BPL in China","authors":"Qingyang Liu, Bingzhen Zhao, Yirong Wang, Jing Hu","doi":"10.1109/ISPLC.2009.4913443","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913443","url":null,"abstract":"With the energy reduction become more and more popular, power company need to build AMR system to improve energy efficiency. Many AMR systems around the world have used PLC as communication channel and it's the same in China. BPL technology has become more mature, and it's reliability, stability and practicality has been verified in a number of field trial which shows great potential in the future market. This paper introduces the status of AMR in China at first, and shows two typical application cases of AMR system based on BPL, and also describes the perspective of this solution. The use of BPL technology in AMR system laid the foundation of smart grid in the future.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"45 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120911317","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913418
Keita Watanabe, D. Umehara, S. Denno, M. Morikura
In this paper, we propose an initial acuisition method for channel synchronization on in-home broadband power line communication (PLC). It has been considered that the time fluctuation in the transfer function has been smaller than that in the noise on the in-home broadband PLC. However, we have observed that the extensively and rapidly time fluctuation across the whole frequency band appears in the in-home PLC at the half of power cycle intervals while connecting some switching power supply devices. Such largely and quickly time fluctuation makes the extensive degradation in performance of in-home PLC devices. Therefore, we should estimate the timing of time fluctuation and synchronize the in-home PLC systems with the estimated time fluctuation. We evaluate the performance of the proposed initial acquisition method under impulsive noise environments and investigate its feasibility for the real in-home PLC.
{"title":"An initial acquisition method for channel synchronization on In-home power line communications","authors":"Keita Watanabe, D. Umehara, S. Denno, M. Morikura","doi":"10.1109/ISPLC.2009.4913418","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913418","url":null,"abstract":"In this paper, we propose an initial acuisition method for channel synchronization on in-home broadband power line communication (PLC). It has been considered that the time fluctuation in the transfer function has been smaller than that in the noise on the in-home broadband PLC. However, we have observed that the extensively and rapidly time fluctuation across the whole frequency band appears in the in-home PLC at the half of power cycle intervals while connecting some switching power supply devices. Such largely and quickly time fluctuation makes the extensive degradation in performance of in-home PLC devices. Therefore, we should estimate the timing of time fluctuation and synchronize the in-home PLC systems with the estimated time fluctuation. We evaluate the performance of the proposed initial acquisition method under impulsive noise environments and investigate its feasibility for the real in-home PLC.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121166445","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913452
Jae-Jo Lee, Hui-Myoung Oh, Dong-Seok In, Dae-Eun Lee, S. Shon
In this paper, a non-intrusive blocking filter for Broadband Power Line Communication(BPLC) without magnetic saturation to high current has been first proposed and designed. The non-intrusive blocking filter consists of a blocking filter core to attenuate BPLC signals and a magnetic saturation prevention circuit to prevent a blocking filter core from magnetic saturation. Ferrite for EMI filter is used as the blocking filter core to obtain broadband attenuation characteristic in BPLC frequency range. The magnetic saturation prevention circuit consists of a Current Transformer(CT), a low pass filter, a phase delay compensation circuit, and a driver circuit. Performance of the blocking filter core is verified to measure attenuation characteristic in the BPLC frequency range. The performance of the magnetic saturation prevention circuit is verified to measure whether a magnetic saturation is caused or not depending on magnitude of current.
{"title":"A study on non-intrusive blocking filter with non-saturation characteristic to high current","authors":"Jae-Jo Lee, Hui-Myoung Oh, Dong-Seok In, Dae-Eun Lee, S. Shon","doi":"10.1109/ISPLC.2009.4913452","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913452","url":null,"abstract":"In this paper, a non-intrusive blocking filter for Broadband Power Line Communication(BPLC) without magnetic saturation to high current has been first proposed and designed. The non-intrusive blocking filter consists of a blocking filter core to attenuate BPLC signals and a magnetic saturation prevention circuit to prevent a blocking filter core from magnetic saturation. Ferrite for EMI filter is used as the blocking filter core to obtain broadband attenuation characteristic in BPLC frequency range. The magnetic saturation prevention circuit consists of a Current Transformer(CT), a low pass filter, a phase delay compensation circuit, and a driver circuit. Performance of the blocking filter core is verified to measure attenuation characteristic in the BPLC frequency range. The performance of the magnetic saturation prevention circuit is verified to measure whether a magnetic saturation is caused or not depending on magnitude of current.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124089165","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913424
T. Hayasaki, D. Umehara, S. Denno, M. Morikura
The in-home broadband power line communication (PLC) is drawing attention to us lately. The broadband PLC has regulation issues for the coexistence with shortwave wireless systems. Therefore, orthogonal frequency division multiplexing (OFDM) is adopted for the broadband PLC. On the other hand, the power line channels suffer from frequency selective fading. It is effective to load appropriate bits on each subcarrier in the OFDM for PLC. In this paper, we propose a bit loading algorithm that maximizes the bit rate by optimizing not only the bit quantity on each subcarrier but also the whole code rate of the forward error correction (FEC) code subject to constraints on the total bit error rate (BER) and power on each subcarrier. Furthermore, we investigate orthogonal frequency division multiple access (OFDMA) as a multiple access scheme on the in-home power line networks. We show that the proposed OFDMA scheme is superior to a time division multiple access (TDMA) scheme from the viewpoint of throughput by computer simulations.
{"title":"A bit-Loaded OFDMA for in-home power line communications","authors":"T. Hayasaki, D. Umehara, S. Denno, M. Morikura","doi":"10.1109/ISPLC.2009.4913424","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913424","url":null,"abstract":"The in-home broadband power line communication (PLC) is drawing attention to us lately. The broadband PLC has regulation issues for the coexistence with shortwave wireless systems. Therefore, orthogonal frequency division multiplexing (OFDM) is adopted for the broadband PLC. On the other hand, the power line channels suffer from frequency selective fading. It is effective to load appropriate bits on each subcarrier in the OFDM for PLC. In this paper, we propose a bit loading algorithm that maximizes the bit rate by optimizing not only the bit quantity on each subcarrier but also the whole code rate of the forward error correction (FEC) code subject to constraints on the total bit error rate (BER) and power on each subcarrier. Furthermore, we investigate orthogonal frequency division multiple access (OFDMA) as a multiple access scheme on the in-home power line networks. We show that the proposed OFDMA scheme is superior to a time division multiple access (TDMA) scheme from the viewpoint of throughput by computer simulations.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117069315","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913398
J. A. Cortés, L. Díez, F. Cañete, J. López
Indoor broadband power-line noise is composed of three main terms: impulsive components, narrowband interferences and background noise. Impulsive components can be classified into three groups according to their behavior with respect to the mains cycle: periodic synchronous with the mains, periodic asynchronous with the mains and aperiodic. Periodic asynchronous terms are the most interesting ones because they have significant spectral components in the band used by broadband power-line communication systems. This paper presents a detailed analysis of this noise component in the frequency band up to 25MHz. By means of a methodology that combines both frequency and time domain techniques, repetition rates and pulse waveforms are obtained even in scenarios in which the remaining noise terms have significant level.
{"title":"Analysis of the periodic impulsive noise asynchronous with the mains in indoor PLC channels","authors":"J. A. Cortés, L. Díez, F. Cañete, J. López","doi":"10.1109/ISPLC.2009.4913398","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913398","url":null,"abstract":"Indoor broadband power-line noise is composed of three main terms: impulsive components, narrowband interferences and background noise. Impulsive components can be classified into three groups according to their behavior with respect to the mains cycle: periodic synchronous with the mains, periodic asynchronous with the mains and aperiodic. Periodic asynchronous terms are the most interesting ones because they have significant spectral components in the band used by broadband power-line communication systems. This paper presents a detailed analysis of this noise component in the frequency band up to 25MHz. By means of a methodology that combines both frequency and time domain techniques, repetition rates and pulse waveforms are obtained even in scenarios in which the remaining noise terms have significant level.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130816505","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 : 2009-05-08DOI: 10.1109/ISPLC.2009.4913396
S. Galli
We report for the first time some statistical properties of the indoor power line (PL) channel that exhibit some interesting similarities to the wireless channel, although some fundamental differences are also pointed out. In particular, we argue here that, while multipath propagation in wireless channels gives rise to Rayleigh distributed fading, multipath in PL channels gives rise to lognormally distributed fading similarly to shadow fading. We also report for the first time that both channel gain and Root-Mean-Square Delay Spread (RMS-DS) of indoor channels are lognormally distributed, leptokurtic and negatively correlated, thus suggesting that channels that introduce severe multipath are also characterized by large attenuation. These results are used to define a simplified PL channel model useful for comparative analysis of communication schemes and, at the same time, to draw some general conclusions on the design of multicarrier schemes.
{"title":"A simplified model for the indoor power line channel","authors":"S. Galli","doi":"10.1109/ISPLC.2009.4913396","DOIUrl":"https://doi.org/10.1109/ISPLC.2009.4913396","url":null,"abstract":"We report for the first time some statistical properties of the indoor power line (PL) channel that exhibit some interesting similarities to the wireless channel, although some fundamental differences are also pointed out. In particular, we argue here that, while multipath propagation in wireless channels gives rise to Rayleigh distributed fading, multipath in PL channels gives rise to lognormally distributed fading similarly to shadow fading. We also report for the first time that both channel gain and Root-Mean-Square Delay Spread (RMS-DS) of indoor channels are lognormally distributed, leptokurtic and negatively correlated, thus suggesting that channels that introduce severe multipath are also characterized by large attenuation. These results are used to define a simplified PL channel model useful for comparative analysis of communication schemes and, at the same time, to draw some general conclusions on the design of multicarrier schemes.","PeriodicalId":321296,"journal":{"name":"2009 IEEE International Symposium on Power Line Communications and Its Applications","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126700854","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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