Pub Date : 2019-04-01DOI: 10.1109/RADIOELEK.2019.8733572
Richard Orjesek, R. Jarina, M. Chmulik, M. Kuba
Music emotion is an important component in the field of music information retrieval and computational musicology. Considering the complexity of the state-of-the-art methods and challenges brought by lack of information available in existing public databases, we propose novel approach to emotion recognition based on convolutional and recurrent neural networks for feature mining. The proposed method utilizes a latest findings in deep learning by stacking convolution layer with bidirectional gated recurrent unit. The method was evaluated on the MediaEval Emotion in Music dataset and has shown exceptional performance using only raw audio signals and without any need for pre-processing.
音乐情感是音乐信息检索和计算音乐学领域的重要组成部分。考虑到最先进的方法的复杂性和现有公共数据库缺乏可用信息所带来的挑战，我们提出了基于卷积和递归神经网络特征挖掘的情感识别新方法。该方法利用深度学习领域的最新研究成果，将卷积层与双向门控循环单元叠加。该方法在MediaEval Emotion in Music数据集上进行了评估，仅使用原始音频信号且不需要任何预处理，就显示出了出色的性能。
{"title":"DNN Based Music Emotion Recognition from Raw Audio Signal","authors":"Richard Orjesek, R. Jarina, M. Chmulik, M. Kuba","doi":"10.1109/RADIOELEK.2019.8733572","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733572","url":null,"abstract":"Music emotion is an important component in the field of music information retrieval and computational musicology. Considering the complexity of the state-of-the-art methods and challenges brought by lack of information available in existing public databases, we propose novel approach to emotion recognition based on convolutional and recurrent neural networks for feature mining. The proposed method utilizes a latest findings in deep learning by stacking convolution layer with bidirectional gated recurrent unit. The method was evaluated on the MediaEval Emotion in Music dataset and has shown exceptional performance using only raw audio signals and without any need for pre-processing.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"17 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":"117291737","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.2019.8733544
L. Langhammer, R. Sotner, T. Dostál
This contribution provides a novel solution of a reconnection-less reconfigurable filter based on voltage differencing transconductance amplifiers (VDTAs) and variable gain amplifier (VGA). The structure offers the 2nd-order functions of all pass, band stop, low pass, low pass with transfer zero alongside with the 1st-order high-pass function and direct transfer in dependence on setting of DC voltages. The electronic control of pole frequency and quality factor of the filter is provided. Furthermore, the filter can change its pole frequency while maintaining bandwidth constant. Simulations in Cadence IC6 (spectre) software were performed to verify the design.
{"title":"New Solution of a Frequency Filter with Reconnection-less Reconfiguration of Its Transfer","authors":"L. Langhammer, R. Sotner, T. Dostál","doi":"10.1109/RADIOELEK.2019.8733544","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733544","url":null,"abstract":"This contribution provides a novel solution of a reconnection-less reconfigurable filter based on voltage differencing transconductance amplifiers (VDTAs) and variable gain amplifier (VGA). The structure offers the 2nd-order functions of all pass, band stop, low pass, low pass with transfer zero alongside with the 1st-order high-pass function and direct transfer in dependence on setting of DC voltages. The electronic control of pole frequency and quality factor of the filter is provided. Furthermore, the filter can change its pole frequency while maintaining bandwidth constant. Simulations in Cadence IC6 (spectre) software were performed to verify the design.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"4290 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":"125783838","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}
This paper assumes that the Laplacian model is valid for the middle frequency DCT coefficients of a JPEG image and considers embedding with a two coefficient version of the Koch and Zhao stego algorithm. Under some mederate conditions, one can get a dependency of the cover image PSNR vs payload and embedding threshold. Employing some algebra allows us to substitute this bulk expression for an approximate but simple one. Next, solving the resulting equation for the embedding threshold, given PSNR and payload, yields us an approximate value of the threshold. On the other hand, by solving numerically the original, non-simplified equation, we get the math-model-accurate value of the threshold. Thus, it becomes possible to compare two threshold values (accurate and approximate). This comparison has been done for different texture-like images and results are listed below.
{"title":"Tuning Parameters of the Koch and Zhao Stego Algorithm","authors":"Oleksii Fedorov, Anatolii Omelchenko, Andrii Yaurov","doi":"10.1109/RADIOELEK.2019.8733473","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733473","url":null,"abstract":"This paper assumes that the Laplacian model is valid for the middle frequency DCT coefficients of a JPEG image and considers embedding with a two coefficient version of the Koch and Zhao stego algorithm. Under some mederate conditions, one can get a dependency of the cover image PSNR vs payload and embedding threshold. Employing some algebra allows us to substitute this bulk expression for an approximate but simple one. Next, solving the resulting equation for the embedding threshold, given PSNR and payload, yields us an approximate value of the threshold. On the other hand, by solving numerically the original, non-simplified equation, we get the math-model-accurate value of the threshold. Thus, it becomes possible to compare two threshold values (accurate and approximate). This comparison has been done for different texture-like images and results are listed below.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"28 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":"121281091","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.2019.8733554
A. Serov, A. A. Shatokhin, G. Antipov
Nowdays, measurements of different power quality parameters are based on spectrum measurements by application of Fast Fourier Transform (FFT). At the same time, in order to eliminate the "spectrum leakage" effect, measurement time should be a multiple of the input signal period. Frequency of real power grids is variable. For successful FFT application, the number of processed samples must be equal to a power of two or four. It calls for periodic measurement of the frequency of the input signal and oversampling. A sample rate converter (SRC) is applied to perform resampling. In this article a method of spectrum measurement and apparent power measurement, based on the application of FFT and SRC is described. Measurement errors of these values, due to inaccurate sampling frequency adjustment are analyzed. A SRC based on the Lagrange interpolator is considered. The Lagrange interpolator is implemented on the Farrow structure (Farrow Filter). Analytical expressions are obtained for estimating the error of the magnitude response and phase response of digital SRC of the order from zero to fourth.
{"title":"Sample Rate Converter As a Means of Reducing Measurment Error of the Voltage Spectrum by Application of FFT","authors":"A. Serov, A. A. Shatokhin, G. Antipov","doi":"10.1109/RADIOELEK.2019.8733554","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733554","url":null,"abstract":"Nowdays, measurements of different power quality parameters are based on spectrum measurements by application of Fast Fourier Transform (FFT). At the same time, in order to eliminate the \"spectrum leakage\" effect, measurement time should be a multiple of the input signal period. Frequency of real power grids is variable. For successful FFT application, the number of processed samples must be equal to a power of two or four. It calls for periodic measurement of the frequency of the input signal and oversampling. A sample rate converter (SRC) is applied to perform resampling. In this article a method of spectrum measurement and apparent power measurement, based on the application of FFT and SRC is described. Measurement errors of these values, due to inaccurate sampling frequency adjustment are analyzed. A SRC based on the Lagrange interpolator is considered. The Lagrange interpolator is implemented on the Farrow structure (Farrow Filter). Analytical expressions are obtained for estimating the error of the magnitude response and phase response of digital SRC of the order from zero to fourth.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"24 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":"116709805","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.2019.8733435
Josef Jordán
The aim of this paper is to purpose a methodical algorithm how to measure and analyze complex vibration patterns of an antenna gearbox. The main problem is to analyze the health of a gearbox without knowing the exact state of the gearings inside. In many cases it is not possible to an exact number of gearings and number of teeth on each gearing. The technique to obtain the health condition of the whole gearbox is to take a complete picture of vibration measured with a gearbox in good condition, and then compare it to vibrations of an aged gearbox, based on cepstral analysis. Measurements were made from very low frequencies 1Hz up to 12.5 kHz. The Analog to Digital Converter (ADC) used for this application has a resolution of 24 bits with a 25 kHz sampling rate. The digital signal is windowed by a Hann function and then the CEPSTRUM is calculated. Because of the impossibility of measuring of a worn gearbox, this study only shows the results measured on the new gearbox. The methodology how to measure and analyze internal vibrations of a gearbox is shown in this study and what results can be expected from those measurements.
{"title":"Vibration Measurement and Analysis of Mechanical Design of the Antenna Radar System","authors":"Josef Jordán","doi":"10.1109/RADIOELEK.2019.8733435","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733435","url":null,"abstract":"The aim of this paper is to purpose a methodical algorithm how to measure and analyze complex vibration patterns of an antenna gearbox. The main problem is to analyze the health of a gearbox without knowing the exact state of the gearings inside. In many cases it is not possible to an exact number of gearings and number of teeth on each gearing. The technique to obtain the health condition of the whole gearbox is to take a complete picture of vibration measured with a gearbox in good condition, and then compare it to vibrations of an aged gearbox, based on cepstral analysis. Measurements were made from very low frequencies 1Hz up to 12.5 kHz. The Analog to Digital Converter (ADC) used for this application has a resolution of 24 bits with a 25 kHz sampling rate. The digital signal is windowed by a Hann function and then the CEPSTRUM is calculated. Because of the impossibility of measuring of a worn gearbox, this study only shows the results measured on the new gearbox. The methodology how to measure and analyze internal vibrations of a gearbox is shown in this study and what results can be expected from those measurements.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"6 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":"131453484","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.2019.8733421
L. Nagy, A. Chvála, J. Marek, M. Potocný, V. Stopjaková
This paper addresses static as well as dynamic performance analysis of a standard ESD structure fabricated in 130 nm CMOS technology. The original design of the ESD structures was aimed at power supply voltage of 1.2 V and usage of grounded-gate NMOS and PMOS devices. We investigated the properties of the presented ESD structure using a lowered value of the supply voltage, since the target application will be within a low-voltage / low-power systems with VDD = 0.6 V and VDD = 0.4 V. The comparison of the measured and simulated data is carried out and discussed. The paper also deals with the development of a novel high-accuracy VerilogA model in order to use more realistic load created by real ESD structures.
{"title":"Performance Analysis of ESD Structures in 130 nm CMOS Technology for Low-Power Applications","authors":"L. Nagy, A. Chvála, J. Marek, M. Potocný, V. Stopjaková","doi":"10.1109/RADIOELEK.2019.8733421","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733421","url":null,"abstract":"This paper addresses static as well as dynamic performance analysis of a standard ESD structure fabricated in 130 nm CMOS technology. The original design of the ESD structures was aimed at power supply voltage of 1.2 V and usage of grounded-gate NMOS and PMOS devices. We investigated the properties of the presented ESD structure using a lowered value of the supply voltage, since the target application will be within a low-voltage / low-power systems with VDD = 0.6 V and VDD = 0.4 V. The comparison of the measured and simulated data is carried out and discussed. The paper also deals with the development of a novel high-accuracy VerilogA model in order to use more realistic load created by real ESD structures.","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":"128693201","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.2019.8733502
David Conka, A. Cizmár
Safety is one of the society requirement, what we need for cheerful live. The principal purpose is to recognize potentially dangerous acoustic events (gun shooting and glass breaking). This document compares a Neural Network (NN) based on the detection system and a hidden Markov model based on the acoustic event detector. For both methods, the same database was used. The database consisted of shots, glass breaks and background noise. Proposed deep neural network processes an acoustic signal through two hidden layers. The whole process may divide into three parts. Training, testing and evaluation part. As the main resulting parameter accuracy has been chosen. This computation process uses a confusion matrix for reliable detection. Accuracy is compared with previous research in this area, as well.
{"title":"Acoustic Events Processing with Deep Neural Network","authors":"David Conka, A. Cizmár","doi":"10.1109/RADIOELEK.2019.8733502","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733502","url":null,"abstract":"Safety is one of the society requirement, what we need for cheerful live. The principal purpose is to recognize potentially dangerous acoustic events (gun shooting and glass breaking). This document compares a Neural Network (NN) based on the detection system and a hidden Markov model based on the acoustic event detector. For both methods, the same database was used. The database consisted of shots, glass breaks and background noise. Proposed deep neural network processes an acoustic signal through two hidden layers. The whole process may divide into three parts. Training, testing and evaluation part. As the main resulting parameter accuracy has been chosen. This computation process uses a confusion matrix for reliable detection. Accuracy is compared with previous research in this area, as well.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"13 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":"131903855","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.2019.8733456
A. Ivutin, A. Troshina, A. Novikov
The article presents an approach to automatic transformation of sequential code in parallel for a given multicore architecture. A generalized code transformation methodology based on its intermediate low-level representation and the mathematical apparatus of Petri nets with additional semantic relations is presented. The algorithm of automatic parallelization of the linear and cyclic structures based on equivalent transformations of the initial net of the sequential algorithm is presented. The paper shows the experiments for automated parallelization of the linear algorithm.
{"title":"Low-level Code Auto-tuning for State-of-the-art Multicore Architectures","authors":"A. Ivutin, A. Troshina, A. Novikov","doi":"10.1109/RADIOELEK.2019.8733456","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733456","url":null,"abstract":"The article presents an approach to automatic transformation of sequential code in parallel for a given multicore architecture. A generalized code transformation methodology based on its intermediate low-level representation and the mathematical apparatus of Petri nets with additional semantic relations is presented. The algorithm of automatic parallelization of the linear and cyclic structures based on equivalent transformations of the initial net of the sequential algorithm is presented. The paper shows the experiments for automated parallelization of the linear algorithm.","PeriodicalId":336454,"journal":{"name":"2019 29th International Conference Radioelektronika (RADIOELEKTRONIKA)","volume":"31 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":"128950292","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.2019.8733533
M. Nedvedova, J. Marek
The paper is part of a broader study to utilize some hypotheses, methodologies and tools from Computational Aesthetics, the foundations of which were created in C.R. Shannon’s "The Mathematical Theory of Information". Using the basic ideas of computational aesthetics, a picture can be seen as a message. Cybernetic aesthetics introduces information flow to describe perceptible information. Further cybernetic aesthetic proposes characteristics for conspicuity and intelligibility of artwork. In the sample survey, using these variables, we try to measure the quantity of perceptible information in the image. In the literature, human perceptual capacity values are reported close to 15 bits per second. Our aim will be to verify this information. We will do our study with 200 responses of 35 respondents, where we will measure their ability to perceive different elements in M.C. Escher's "wallpaper" paintings. Part of the study will be a statistical evaluation of the measurement.
{"title":"Estimation of the Capacity of Human Perception using Computational Aesthetics","authors":"M. Nedvedova, J. Marek","doi":"10.1109/RADIOELEK.2019.8733533","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733533","url":null,"abstract":"The paper is part of a broader study to utilize some hypotheses, methodologies and tools from Computational Aesthetics, the foundations of which were created in C.R. Shannon’s \"The Mathematical Theory of Information\". Using the basic ideas of computational aesthetics, a picture can be seen as a message. Cybernetic aesthetics introduces information flow to describe perceptible information. Further cybernetic aesthetic proposes characteristics for conspicuity and intelligibility of artwork. In the sample survey, using these variables, we try to measure the quantity of perceptible information in the image. In the literature, human perceptual capacity values are reported close to 15 bits per second. Our aim will be to verify this information. We will do our study with 200 responses of 35 respondents, where we will measure their ability to perceive different elements in M.C. Escher's \"wallpaper\" paintings. Part of the study will be a statistical evaluation of the 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":"128655667","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.2019.8733460
L. Rejfek, J. Urbář, K. Pitaš, P. Chmelar
In this paper is described the measurement of the Total Electron Content by the single-frequency GPS receiver. Disadvantage of this method is that it cannot be used for real-time processing. The advantages of the proposed method are that the device is cheaper than dual-frequency GPS receiver and it can reinterpret older valuable measurements by such single-frequency receivers. The algorithm was tested with the dual-frequency receiver. Signal from selected frequency (f1, or f2) was processed by presented algorithm and results were compared with standard processing of the signals, which is used for the dual-frequency receivers. Results are promising.
{"title":"Total Electron Content Measurements by Single-Frequency GPS Receiver","authors":"L. Rejfek, J. Urbář, K. Pitaš, P. Chmelar","doi":"10.1109/RADIOELEK.2019.8733460","DOIUrl":"https://doi.org/10.1109/RADIOELEK.2019.8733460","url":null,"abstract":"In this paper is described the measurement of the Total Electron Content by the single-frequency GPS receiver. Disadvantage of this method is that it cannot be used for real-time processing. The advantages of the proposed method are that the device is cheaper than dual-frequency GPS receiver and it can reinterpret older valuable measurements by such single-frequency receivers. The algorithm was tested with the dual-frequency receiver. Signal from selected frequency (f1, or f2) was processed by presented algorithm and results were compared with standard processing of the signals, which is used for the dual-frequency receivers. Results are promising.","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":"122408346","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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