Pub Date : 2024-07-09DOI: 10.23919/comex.2024XBL0064
Shin-Ichi Yamamoto;Hiroto Ado;Ryuya Seki
When reflector antennas with a beam waveguide feeding system are used in an array configuration, the transmission phase of each reflector antenna must be known and corrected. In this paper, we propose a method in which a reflector plate is placed in the center hole of the main reflector, the reflected phase at the primary radiator horn is measured, and half of the measured phase is used as the transmission phase of the beam waveguide feeding system. The proposed method was verified by calculation, measurement using a simple model with the same path length, and measurement using an actual reflector antenna, and its effectiveness was confirmed.
{"title":"Phase Measurement and Adjustment of Reflector Antenna with Beam Waveguide Feeds","authors":"Shin-Ichi Yamamoto;Hiroto Ado;Ryuya Seki","doi":"10.23919/comex.2024XBL0064","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0064","url":null,"abstract":"When reflector antennas with a beam waveguide feeding system are used in an array configuration, the transmission phase of each reflector antenna must be known and corrected. In this paper, we propose a method in which a reflector plate is placed in the center hole of the main reflector, the reflected phase at the primary radiator horn is measured, and half of the measured phase is used as the transmission phase of the beam waveguide feeding system. The proposed method was verified by calculation, measurement using a simple model with the same path length, and measurement using an actual reflector antenna, and its effectiveness was confirmed.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 9","pages":"367-370"},"PeriodicalIF":0.3,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10591716","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091033","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 : 2024-07-09DOI: 10.23919/comex.2024XBL0098
Kai Ikuta;Yuta Ito;Moriya Nakamura
We investigated a nonlinear equalizer based on reservoir computing (RC) with tapped-delay lines for compensating for linear and nonlinear waveform distortion caused by, e.g., chromatic dispersion and self-phase modulation. We evaluated and compared the equalization performance of RC systems with and without tapped-delay lines by numerical simulation, while varying the parameters and the transmission distance. The proposed equalizer construction enables the use of RC with a shorter time-constant than that used for conventional RC-based nonlinear equalizers.
{"title":"Optical Nonlinearity Mitigation Using Reservoir Computing with Tapped-Delay Lines","authors":"Kai Ikuta;Yuta Ito;Moriya Nakamura","doi":"10.23919/comex.2024XBL0098","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0098","url":null,"abstract":"We investigated a nonlinear equalizer based on reservoir computing (RC) with tapped-delay lines for compensating for linear and nonlinear waveform distortion caused by, e.g., chromatic dispersion and self-phase modulation. We evaluated and compared the equalization performance of RC systems with and without tapped-delay lines by numerical simulation, while varying the parameters and the transmission distance. The proposed equalizer construction enables the use of RC with a shorter time-constant than that used for conventional RC-based nonlinear equalizers.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 9","pages":"384-388"},"PeriodicalIF":0.3,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10591710","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091061","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}
As machine learning research in the networking field has become more active in recent years, the demand for network traffic datasets has increased. On the other hand, the amount and types of publicly available network traffic datasets are scarce as training datasets for machine learning. Therefore, we focus on the generative adversarial network (GAN) as a data generation model, aiming to use generated rather than publicly available training datasets. However, existing GANs have difficulty generating sufficiently diverse network traffic to improve generalization ability while representing variations across weekdays, weekends, and date. This study proposes a new layers inserted into the conditional GAN model with the functions of expanding dimensionality of time-series traffic data and embedding temporal position information. Experimental results show that the model with the proposed layers inserted generated diverse network traffic data that represents temporal features.
近年来，网络领域的机器学习研究日趋活跃，对网络流量数据集的需求也随之增加。另一方面，作为机器学习的训练数据集，公开可用的网络流量数据集的数量和类型都很少。因此，我们将生成式对抗网络（GAN）作为数据生成模型，旨在使用生成的而非公开可用的训练数据集。然而，现有的生成式对抗网络难以生成足够多样化的网络流量，从而在代表工作日、周末和日期变化的同时提高泛化能力。本研究提出在条件 GAN 模型中插入一个新层，其功能是扩展时间序列流量数据的维度并嵌入时间位置信息。实验结果表明，插入了所建议的层的模型生成了代表时间特征的多样化网络流量数据。
{"title":"Proposal of Temporal Feature Layers for Network Traffic Dataset Generation Using C-GAN","authors":"Yukito Onodera;Erina Takeshita;Tomoya Kosugi;Satoshi Suzuki","doi":"10.23919/comex.2024XBL0062","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0062","url":null,"abstract":"As machine learning research in the networking field has become more active in recent years, the demand for network traffic datasets has increased. On the other hand, the amount and types of publicly available network traffic datasets are scarce as training datasets for machine learning. Therefore, we focus on the generative adversarial network (GAN) as a data generation model, aiming to use generated rather than publicly available training datasets. However, existing GANs have difficulty generating sufficiently diverse network traffic to improve generalization ability while representing variations across weekdays, weekends, and date. This study proposes a new layers inserted into the conditional GAN model with the functions of expanding dimensionality of time-series traffic data and embedding temporal position information. Experimental results show that the model with the proposed layers inserted generated diverse network traffic data that represents temporal features.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 8","pages":"319-322"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554803","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973490","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}
Comparing the bandwidths of a crossed spherical helix antenna (XSHA) and conventional antennas is challenging owing to significant change in the radiation efficiency with respect to frequency even at low voltage standing wave ratio (VSWR). Thus, two types of evaluation were performed in this work to demonstrate the wideband property of XSHA. First, the antennas were assumed to be made of a perfect conductor and were compared regarding only the VSWR bandwidth. Next, we compared the bandwidth at radiation efficiency of lossy antennas based on the generalized effective fractional bandwidth $(B_{e}). B_{e}$ is the product of the bandwidth and the radiation efficiency varying with frequency. Numerical simulations were conducted to compare the bandwidths for $VSWR leq 3$ . The bandwidth of the XSHA is 2.19 and 2.11 times wider than those of single resonance antenna in lossless and lossy cases, respectively. Compared with a dual resonance antenna, the bandwidth of the XSHA is 1.36 times greater at acceptable radiation efficiencies of 50%.
{"title":"Two Types of Bandwidth Evaluation of Crossed Spherical Helix Antennas Using Numerical Simulation","authors":"Takuma Shimada;Mina Nishie;Keisuke Noguchi;Masato Odagaki;Keisuke Fujita","doi":"10.23919/comex.2024XBL0038","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0038","url":null,"abstract":"Comparing the bandwidths of a crossed spherical helix antenna (XSHA) and conventional antennas is challenging owing to significant change in the radiation efficiency with respect to frequency even at low voltage standing wave ratio (VSWR). Thus, two types of evaluation were performed in this work to demonstrate the wideband property of XSHA. First, the antennas were assumed to be made of a perfect conductor and were compared regarding only the VSWR bandwidth. Next, we compared the bandwidth at radiation efficiency of lossy antennas based on the generalized effective fractional bandwidth \u0000<tex>$(B_{e}). B_{e}$</tex>\u0000 is the product of the bandwidth and the radiation efficiency varying with frequency. Numerical simulations were conducted to compare the bandwidths for \u0000<tex>$VSWR leq 3$</tex>\u0000. The bandwidth of the XSHA is 2.19 and 2.11 times wider than those of single resonance antenna in lossless and lossy cases, respectively. Compared with a dual resonance antenna, the bandwidth of the XSHA is 1.36 times greater at acceptable radiation efficiencies of 50%.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 9","pages":"351-354"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554804","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091062","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}
Intelligent reflecting surface (IRS), which can reflect radio waves controlling the phase of incident radio waves, is being investigated for wireless communication in high-frequency bands. To control the reflection characteristic, it is necessary to separately estimate a large number of channel coefficients between transmitting and receiving antennas through each IRS element. This causes significant overhead for the channel estimation. We have proposed a channel prediction method to reduce the overhead using Gaussian process regression with spectral mixture kernel. In Gaussian process regression, the determination of the hyperparameters used to calculate the kernel matrix has a significant impact on prediction accuracy. In this study, we propose validation-based hyperparameter determination for GPR-based channel prediction and evaluate the performance difference between the gradient method and validation.
{"title":"On Hyperparameter Determination for GPR-Based Channel Prediction in IRS-Assisted Wireless Communication Systems","authors":"Norisato Suga;Kazuto Yano;Yafei Hou;Toshikazu Sakano","doi":"10.23919/comex.2024XBL0058","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0058","url":null,"abstract":"Intelligent reflecting surface (IRS), which can reflect radio waves controlling the phase of incident radio waves, is being investigated for wireless communication in high-frequency bands. To control the reflection characteristic, it is necessary to separately estimate a large number of channel coefficients between transmitting and receiving antennas through each IRS element. This causes significant overhead for the channel estimation. We have proposed a channel prediction method to reduce the overhead using Gaussian process regression with spectral mixture kernel. In Gaussian process regression, the determination of the hyperparameters used to calculate the kernel matrix has a significant impact on prediction accuracy. In this study, we propose validation-based hyperparameter determination for GPR-based channel prediction and evaluate the performance difference between the gradient method and validation.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 8","pages":"315-318"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554672","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973496","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}
One possible approach to address communication delay in the complex wireless environment of manufacturing sites is to predict the delay by system-level simulator (SLS) and notify the communication control system in advance. For accurate delay prediction, the carrier sense (CS) model in SLS should incorporate real device characteristics. However, accurate modeling of CS is difficult since its implementation specifications are usually not publicly available. In this letter, we propose a method for estimating CS characteristics using electromagnetic noise generated simulatively by software-defined radio and emitted from a microwave oven and verify the effectiveness of this method.
{"title":"Measurement-Based Estimation of Carrier Sense Behavior for Simulation Modeling","authors":"Ayano Ohnishi;Tetsuya Iye;Michio Miyamoto;Takahito Inoshita","doi":"10.23919/comex.2024XBL0045","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0045","url":null,"abstract":"One possible approach to address communication delay in the complex wireless environment of manufacturing sites is to predict the delay by system-level simulator (SLS) and notify the communication control system in advance. For accurate delay prediction, the carrier sense (CS) model in SLS should incorporate real device characteristics. However, accurate modeling of CS is difficult since its implementation specifications are usually not publicly available. In this letter, we propose a method for estimating CS characteristics using electromagnetic noise generated simulatively by software-defined radio and emitted from a microwave oven and verify the effectiveness of this method.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 8","pages":"323-326"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554801","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973468","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 : 2024-06-11DOI: 10.23919/comex.2024XBL0067
Hironao Abe;Hideo Kawata;Yuhei Kawakami;Akifumi Tanase;Shinichi Yoshihara;Tomoaki Yoshida
IEEE802.1Qbv Time-Aware Shaper (TAS) has attracted attention as a technology to realize low-delay communication in various fields. Especially in industrial networks, the demand for low-latency communication between remote areas is increasing, and the realization of a service provider network (SPNW) using TAS is expected. We consider the scheduling scheme of TAS for SPNW. When the scheduling order cannot be controlled, as in SPNW, the bandwidth utilization efficiency is lower than when the scheduling order is ideal. To cope with such problems, we propose a rescheduling scheme focusing on the difference in scheduling difficulty. However, the increase in computational load due to rescheduling has not been discussed. In this paper, we consider a method to reduce the computation time of the rescheduling method.
IEEE802.1Qbv 时间感知整形器（TAS）作为一种实现低延迟通信的技术，在各个领域都备受关注。特别是在工业网络中，偏远地区之间对低延迟通信的需求日益增长，利用 TAS 实现服务提供商网络（SPNW）成为人们的期待。我们考虑了 SPNW 的 TAS 调度方案。在 SPNW 中，当调度顺序无法控制时，带宽利用效率会比调度顺序理想时低。为应对此类问题，我们提出了一种以调度难度差异为重点的重新调度方案。然而，由于重新调度而增加的计算负荷尚未得到讨论。在本文中，我们考虑了一种减少重新调度方法计算时间的方法。
{"title":"Proposal to Reduce Computation Time in TAS Rescheduling Scheme","authors":"Hironao Abe;Hideo Kawata;Yuhei Kawakami;Akifumi Tanase;Shinichi Yoshihara;Tomoaki Yoshida","doi":"10.23919/comex.2024XBL0067","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0067","url":null,"abstract":"IEEE802.1Qbv Time-Aware Shaper (TAS) has attracted attention as a technology to realize low-delay communication in various fields. Especially in industrial networks, the demand for low-latency communication between remote areas is increasing, and the realization of a service provider network (SPNW) using TAS is expected. We consider the scheduling scheme of TAS for SPNW. When the scheduling order cannot be controlled, as in SPNW, the bandwidth utilization efficiency is lower than when the scheduling order is ideal. To cope with such problems, we propose a rescheduling scheme focusing on the difference in scheduling difficulty. However, the increase in computational load due to rescheduling has not been discussed. In this paper, we consider a method to reduce the computation time of the rescheduling method.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 8","pages":"343-346"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554802","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973495","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 : 2024-06-11DOI: 10.23919/comex.2024XBL0091
Masaya Ohta;Koichi Kubota
This research uses deep learning to address the high peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM), which is critical for wireless communications. Although a PAPR-reducing network (PRNet), which is a deep learning model, can be used to suppress the PAPR, its computational cost is huge. In this research, the number of layers in a PRNet model is optimized and a fully connected layer is replaced with a convolution layer to reduce the computational load.
{"title":"PRNet with Convolution Layer for PAPR Reduction of OFDM Signals","authors":"Masaya Ohta;Koichi Kubota","doi":"10.23919/comex.2024XBL0091","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0091","url":null,"abstract":"This research uses deep learning to address the high peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM), which is critical for wireless communications. Although a PAPR-reducing network (PRNet), which is a deep learning model, can be used to suppress the PAPR, its computational cost is huge. In this research, the number of layers in a PRNet model is optimized and a fully connected layer is replaced with a convolution layer to reduce the computational load.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 8","pages":"339-342"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554794","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973489","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}
CAPTCHAs have traditionally been used to deter bots, but ensuring protection against machine learning attacks has become difficult. To tackle this problem, we proposed a CAPTCHA based on color constancy, a human cognitive ability that is difficult for machines to reproduce. Although this method achieved high attack resistance while maintaining usability compared to existing CAPTCHAs, the response time increased due to the color selection operation. To address this, we changed the task to a click-type format while keeping the original concept. Our experimental results show that our method matches the response times of existing CAPTCHAs without compromising attack resistance.
{"title":"Usability Improvement in Color Constancy CAPTCHA","authors":"Shotaro Usuzaki;Wang Yihan;Kentaro Aburada;Hisaaki Yamaba;Kayoko Takatsuka;Tetsuro Katayama;Mirang Park;Naonobu Okazaki","doi":"10.23919/comex.2024XBL0052","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0052","url":null,"abstract":"CAPTCHAs have traditionally been used to deter bots, but ensuring protection against machine learning attacks has become difficult. To tackle this problem, we proposed a CAPTCHA based on color constancy, a human cognitive ability that is difficult for machines to reproduce. Although this method achieved high attack resistance while maintaining usability compared to existing CAPTCHAs, the response time increased due to the color selection operation. To address this, we changed the task to a click-type format while keeping the original concept. Our experimental results show that our method matches the response times of existing CAPTCHAs without compromising attack resistance.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 8","pages":"331-334"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554800","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973528","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 : 2024-06-11DOI: 10.23919/comex.2024XBL0057
Iori Serizawa;Nobuhiro Kuga
This letter proposes a concept of residual noise reduction when using multiple testers for non-contact passive intermodulation (PIM) measurements with near field sensing for array antennas. As described herein, the harmonic balance method and the finite difference time domain method are used for simulation. Examination is conducted for third-order PIMs in two-tone testing in the 2 GHz band. Simulation results indicate that the PIM noise which is weaker than the residual PIM of each tester becomes detectable when using the proposed method. The concept is validated further through experimentation using an equivalent array circuit in the 2 GHz band.
{"title":"System Residual Noise Reduction for Non-Contact Passive Intermodulation Measurements of Array Antennas Using Multiple Testers","authors":"Iori Serizawa;Nobuhiro Kuga","doi":"10.23919/comex.2024XBL0057","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0057","url":null,"abstract":"This letter proposes a concept of residual noise reduction when using multiple testers for non-contact passive intermodulation (PIM) measurements with near field sensing for array antennas. As described herein, the harmonic balance method and the finite difference time domain method are used for simulation. Examination is conducted for third-order PIMs in two-tone testing in the 2 GHz band. Simulation results indicate that the PIM noise which is weaker than the residual PIM of each tester becomes detectable when using the proposed method. The concept is validated further through experimentation using an equivalent array circuit in the 2 GHz band.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 8","pages":"335-338"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10554807","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973488","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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