Pub Date : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733452
Deepika Gupta, H. S. Shekhawat
This work presents a new method for artificial bandwidth extension (ABE) in narrowband telephonic communication. In this regard, we use signal model and H∞ optimization to obtain a synthesis filter for representing the wideband information of a signal. We need to estimate the high-band information in narrowband communication. Hence, we construct a high-band filter which retains the high-band information of the synthesis filter. Signal models may not be the same for different speech signals because of their non-stationary (time-varying) behavior. Hence, a short time processing (framing) is applied to speech signals for converting them into the stationary frames. Signal models of stationary frames may be different. As a result, their high-band filters will vary. So, a Gaussian mixture modelling (GMM) codebook approach is used to store the high-band filters information along with their narrowband information (narrowband feature). This approach is also used to estimate the high-band filter information for a given narrowband feature of the signal. Performance analysis is done for the two types of narrowband information representations.
{"title":"Artificial Bandwidth Extension Using H∞ Optimization and Speech Production Model","authors":"Deepika Gupta, H. S. Shekhawat","doi":"10.1109/RADIOELEK.2019.8733452","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733452","url":null,"abstract":"This work presents a new method for artificial bandwidth extension (ABE) in narrowband telephonic communication. In this regard, we use signal model and H∞ optimization to obtain a synthesis filter for representing the wideband information of a signal. We need to estimate the high-band information in narrowband communication. Hence, we construct a high-band filter which retains the high-band information of the synthesis filter. Signal models may not be the same for different speech signals because of their non-stationary (time-varying) behavior. Hence, a short time processing (framing) is applied to speech signals for converting them into the stationary frames. Signal models of stationary frames may be different. As a result, their high-band filters will vary. So, a Gaussian mixture modelling (GMM) codebook approach is used to store the high-band filters information along with their narrowband information (narrowband feature). This approach is also used to estimate the high-band filter information for a given narrowband feature of the signal. Performance analysis is done for the two types of narrowband information representations.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126743123","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733489
A. Ivutin, A. Troshina, A. Novikov
The article presents an approach to the automation of parallelization based on Petri nets with additional semantic relations. Depending on the architecture of the target computing system, on which the execution of the parallel algorithm is planned, adaptation of the developed parallel algorithm to the existing hardware is required. The paper proposes methods for finding global and local optimum for solving the problem of minimizing the execution time of the algorithm executing on a multicore system. The paper presents the example of application of the proposed method for algorithm adaptation for execution on the processor with two cores.
{"title":"Optimization Strategies for Automated Parallelization for Multicore Architectures","authors":"A. Ivutin, A. Troshina, A. Novikov","doi":"10.1109/RADIOELEK.2019.8733489","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733489","url":null,"abstract":"The article presents an approach to the automation of parallelization based on Petri nets with additional semantic relations. Depending on the architecture of the target computing system, on which the execution of the parallel algorithm is planned, adaptation of the developed parallel algorithm to the existing hardware is required. The paper proposes methods for finding global and local optimum for solving the problem of minimizing the execution time of the algorithm executing on a multicore system. The paper presents the example of application of the proposed method for algorithm adaptation for execution on the processor with two cores.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127377470","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733534
Jānis Eidaks, A. Litvinenko, D. Pikulins, Sergejs Tjukovs
This paper is dedicated to the experimental study of the impact of multi-tone signal with a high peak-to-average power ratio (PAPR) on the performance of wireless power transfer (WPT) using a single stage Cockcroft-Walton voltage multiplier with HSMS-285C diodes. The study is done using unlicensed sub-GHz frequencies 863 – 868 MHz in a laboratory under real-life conditions. Two types of design of radio frequency (RF) energy harvesting device (with and without matching network) are used to demonstrate PAPR impact on WPT performance. Eight sub-carriers summed in-phase are used to produce a multi-tone signal with a high PAPR level. For WPT results comparison, a single-tone signal with the same average power is exploited. For the experimental implementation of WPT, pairs of directional (LP0410 Log Periodic PCB) and omnidirectional (VERT900) antennas are used. Moreover, during the experiments the distance between transmitting and receiving antennas is being changed up to 3.2m. The main objective of the experiment is to find conditions when multi-tone signal with a high PAPR provides substantially higher output power compared to single-tone signal. The experimental measurement process includes evaluating the average power at the RF rectifier circuit output for different signals, distances, antennas, and RF-DC converter circuit designs. Furthermore, an additional WPT experiment is performed and the analysis of channel characteristics in the frequency range of interest is done to investigate the reason of the difference between the harvested power using single-tone and multi-tone signals.
{"title":"The Impact of PAPR on the Wireless Power Transfer in IoT Applications","authors":"Jānis Eidaks, A. Litvinenko, D. Pikulins, Sergejs Tjukovs","doi":"10.1109/RADIOELEK.2019.8733534","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733534","url":null,"abstract":"This paper is dedicated to the experimental study of the impact of multi-tone signal with a high peak-to-average power ratio (PAPR) on the performance of wireless power transfer (WPT) using a single stage Cockcroft-Walton voltage multiplier with HSMS-285C diodes. The study is done using unlicensed sub-GHz frequencies 863 – 868 MHz in a laboratory under real-life conditions. Two types of design of radio frequency (RF) energy harvesting device (with and without matching network) are used to demonstrate PAPR impact on WPT performance. Eight sub-carriers summed in-phase are used to produce a multi-tone signal with a high PAPR level. For WPT results comparison, a single-tone signal with the same average power is exploited. For the experimental implementation of WPT, pairs of directional (LP0410 Log Periodic PCB) and omnidirectional (VERT900) antennas are used. Moreover, during the experiments the distance between transmitting and receiving antennas is being changed up to 3.2m. The main objective of the experiment is to find conditions when multi-tone signal with a high PAPR provides substantially higher output power compared to single-tone signal. The experimental measurement process includes evaluating the average power at the RF rectifier circuit output for different signals, distances, antennas, and RF-DC converter circuit designs. Furthermore, an additional WPT experiment is performed and the analysis of channel characteristics in the frequency range of interest is done to investigate the reason of the difference between the harvested power using single-tone and multi-tone signals.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"164 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132867136","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733499
J. Petrzela
This brief paper describes design process toward the simplest lumped circuit implementation of the hyper-jerk function. This is single nonlinear ordinary differential equation able to produce a variety of the robust dense chaotic attractors. Designed oscillators can be considered as canonical in the sense of minimum total number of the circuit elements required for construction. Circuit concept can be understood as the looped system of composed by the active nonlinear two-port and fully passive ladder frequency filter. Fingerprints of robust chaos are provided via numerical analysis, computer-aided simulation and experimental measurement.
{"title":"On the Canonical Circuit Realizations of Fourth-Order and Fifth-Order Hyperjerk Chaotic Function","authors":"J. Petrzela","doi":"10.1109/RADIOELEK.2019.8733499","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733499","url":null,"abstract":"This brief paper describes design process toward the simplest lumped circuit implementation of the hyper-jerk function. This is single nonlinear ordinary differential equation able to produce a variety of the robust dense chaotic attractors. Designed oscillators can be considered as canonical in the sense of minimum total number of the circuit elements required for construction. Circuit concept can be understood as the looped system of composed by the active nonlinear two-port and fully passive ladder frequency filter. Fingerprints of robust chaos are provided via numerical analysis, computer-aided simulation and experimental measurement.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121203019","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733498
H. Al-amaireh, Z. Kollár
Filter Bank MultiCarrier (FBMC) modulation with one of its variants, the Offset Quadrature Amplitude Modulation (OQAM) is considered as one of the most favored candidates for future 5G air interface. The transceiver architectures of FBMC-OQAM is categorized into two main design approaches: using PolyPhase Network (PPN) and using Frequency Spreading (FS). The PPN approach requires a lower complexity while the FS based architecture shows better performance when considered at the receiver. In this paper we introduce and analyze an improved FS-FBMC receiver architecture which will reduce the required computational load. The proposed structure is based on a recently introduced variant of the sliding Discrete Fourier Transform (DFT) known as Hopping DFT (HDFT). We show that by applying the HDFT, the FS complexity can be reduced.
{"title":"Reducing the Complexity of FS-FBMC Receivers using Hopping DFT","authors":"H. Al-amaireh, Z. Kollár","doi":"10.1109/RADIOELEK.2019.8733498","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733498","url":null,"abstract":"Filter Bank MultiCarrier (FBMC) modulation with one of its variants, the Offset Quadrature Amplitude Modulation (OQAM) is considered as one of the most favored candidates for future 5G air interface. The transceiver architectures of FBMC-OQAM is categorized into two main design approaches: using PolyPhase Network (PPN) and using Frequency Spreading (FS). The PPN approach requires a lower complexity while the FS based architecture shows better performance when considered at the receiver. In this paper we introduce and analyze an improved FS-FBMC receiver architecture which will reduce the required computational load. The proposed structure is based on a recently introduced variant of the sliding Discrete Fourier Transform (DFT) known as Hopping DFT (HDFT). We show that by applying the HDFT, the FS complexity can be reduced.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130369682","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733494
M. Márton, Ľ. Ovseník, J. Turán, M. Spes, J. Urbanský
Communication technologies have the dominant effect to human lives. We are surrounded by these technologies in personal and professional lives too. Digitalization sets the trend in all these areas. Communication technologies easy the fulfillment of our tasks in professionals areas and open the next door of possibilities of spending our free time. Responsibility that was on human, is today directly on end devices. The expansion of these technologies is so significant that it has almost negative impact on human lives. In many cases, we are slaves of technologies. Requirements of users on availability of communication technologies are still growing and we have to offer the solution. Optical fiber communication systems create the backbone of high speed communication systems. We are focused on using optical communication systems without needs of optical fiber. Free Space Optics (FSO) systems offer comparable transmission rates as optical fibers communication systems. The main drawback of FSO technologies is sensitivity to weather changes, so we have to design appropriate radio-frequency (RF) backup link. Analysis of the appropriate type of helix antenna is the point of this paper. We designed three models of helix antennas operating on three different frequencies from non-licensed frequency range.
{"title":"Comparison of Helix Antennas Operated on 2.4, 5.2 and 9.2GHz for FSO/RF Hybrid System","authors":"M. Márton, Ľ. Ovseník, J. Turán, M. Spes, J. Urbanský","doi":"10.1109/RADIOELEK.2019.8733494","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733494","url":null,"abstract":"Communication technologies have the dominant effect to human lives. We are surrounded by these technologies in personal and professional lives too. Digitalization sets the trend in all these areas. Communication technologies easy the fulfillment of our tasks in professionals areas and open the next door of possibilities of spending our free time. Responsibility that was on human, is today directly on end devices. The expansion of these technologies is so significant that it has almost negative impact on human lives. In many cases, we are slaves of technologies. Requirements of users on availability of communication technologies are still growing and we have to offer the solution. Optical fiber communication systems create the backbone of high speed communication systems. We are focused on using optical communication systems without needs of optical fiber. Free Space Optics (FSO) systems offer comparable transmission rates as optical fibers communication systems. The main drawback of FSO technologies is sensitivity to weather changes, so we have to design appropriate radio-frequency (RF) backup link. Analysis of the appropriate type of helix antenna is the point of this paper. We designed three models of helix antennas operating on three different frequencies from non-licensed frequency range.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124636154","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733551
Michael Mesarcik, S. Lewis, A. Mishra, J. Pidanic, Karel Juryca
Wavelets are powerful signal classification tools that show promise for classification in Pulse-Doppler radar applications. A wavelet decomposition of match filtered radar data is performed for a surveillance radar in the Czech Republic. A custom discrete wavelet is designed based on the range profiles of the dataset with and without targets and clutter present. The entropy and energy for different levels of the DWT decomposition are used to determine the presence of various targets. Targets are differentiated from static clutter by thresholding the DWT decomposition levels.
{"title":"Discrete Wavelet Design for Target Classification in Pulse-Doppler Surveillance Radar","authors":"Michael Mesarcik, S. Lewis, A. Mishra, J. Pidanic, Karel Juryca","doi":"10.1109/RADIOELEK.2019.8733551","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733551","url":null,"abstract":"Wavelets are powerful signal classification tools that show promise for classification in Pulse-Doppler radar applications. A wavelet decomposition of match filtered radar data is performed for a surveillance radar in the Czech Republic. A custom discrete wavelet is designed based on the range profiles of the dataset with and without targets and clutter present. The entropy and energy for different levels of the DWT decomposition are used to determine the presence of various targets. Targets are differentiated from static clutter by thresholding the DWT decomposition levels.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132020075","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733461
O. Fiser, K. Pitaš
During first experiments with weather radar PCDR 35 a question of calibration arose. Comparing pixel measurement with the measurement of the same pixel by operational radar we estimated the radar constant to be C3 = 2. 62∙108, which is tuned to the target distance in [km] and to received power in [mW]. Also all main necessary equations from radar meteorology were cleared in this study and the installation of equivalent radar reflectivity factor was explained based on historical development base. The example of radar reflectivity factor measurement in actual rain event is demonstrated.
{"title":"Simple Calibration of FMCIW 35 GHz Meteorological Radar \"PCDR 35\"","authors":"O. Fiser, K. Pitaš","doi":"10.1109/RADIOELEK.2019.8733461","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733461","url":null,"abstract":"During first experiments with weather radar PCDR 35 a question of calibration arose. Comparing pixel measurement with the measurement of the same pixel by operational radar we estimated the radar constant to be C3 = 2. 62∙108, which is tuned to the target distance in [km] and to received power in [mW]. Also all main necessary equations from radar meteorology were cleared in this study and the installation of equivalent radar reflectivity factor was explained based on historical development base. The example of radar reflectivity factor measurement in actual rain event is demonstrated.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124694704","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733480
Tom Bielik, B. Adamec, V. Hottmar
In this paper, design and practical realization of radio frequency (RF) bandpass filter (BPF) with center frequency 756MHz and -3dB bandwidth of 15MHz is presented. BPF is realized by discrete LC components. Each LC component used in BPF circuit has been carefully analyzed and determined by appropriate equivalent circuits, which were created in MATLAB. Subsequently, BPF circuit has been created using these individual circuits. According to obtained BPF circuit in MATLAB, the transmission and reflection parameters can be set properly to acquire desired specifications. Scattering parameter measurements of practically realized BPF were carried out for verification of proposed method.
{"title":"Design and Practical Realization of Lumped Element RF Bandpass Filter","authors":"Tom Bielik, B. Adamec, V. Hottmar","doi":"10.1109/RADIOELEK.2019.8733480","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733480","url":null,"abstract":"In this paper, design and practical realization of radio frequency (RF) bandpass filter (BPF) with center frequency 756MHz and -3dB bandwidth of 15MHz is presented. BPF is realized by discrete LC components. Each LC component used in BPF circuit has been carefully analyzed and determined by appropriate equivalent circuits, which were created in MATLAB. Subsequently, BPF circuit has been created using these individual circuits. According to obtained BPF circuit in MATLAB, the transmission and reflection parameters can be set properly to acquire desired specifications. Scattering parameter measurements of practically realized BPF were carried out for verification of proposed method.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123227957","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 : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733579
A. Zemtsov, I. Artyukhov
Industrial electrotechnical devices, using microwave energy, may consist of several magnetron generators. Packaged magnetrons are often used in microwave energy distributed supply systems. Creating a power supply system for such magnetron group is an exceptional task due to the packaged magnetron features, the technological variation of their parameters and the need to adapt to the general operation mode. The possibility of building a centralized power system using booster elements is considered as an individual power source alternative.
{"title":"Power Supply System for Industrial Packaged Magnetrons Group","authors":"A. Zemtsov, I. Artyukhov","doi":"10.1109/RADIOELEK.2019.8733579","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733579","url":null,"abstract":"Industrial electrotechnical devices, using microwave energy, may consist of several magnetron generators. Packaged magnetrons are often used in microwave energy distributed supply systems. Creating a power supply system for such magnetron group is an exceptional task due to the packaged magnetron features, the technological variation of their parameters and the need to adapt to the general operation mode. The possibility of building a centralized power system using booster elements is considered as an individual power source alternative.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131247591","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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