Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166036
Y. Nechaev, I. Peshkov, N. Fortunova, I. Zaitseva
At present, digital antenna arrays are of growing research interest, since they allow us to form nulls and maxima of the radiation pattern without involving additional devices, but in the processing unit. This paper studies digital beamforming in three-dimensional space, i.e., in azimuth and angle of elevation on the example of a statistically optimal noise reduction algorithm in the channels of the array. A matrix-vector expression was obtained for calculating the vector of weight coefficients in a digital antenna array. The results of modeling a cylindrical antenna array of directive radiators are presented. The characteristics of a cylindrical digital antenna array are studied depending on the SNR (signal-to-noise ratio) for antenna elements with different directivity, and depending on the directive gain of antenna elements. The characteristics of digital beamforming, such as peak power, side lobe level, null depth, antenna gain, and others, were evaluated.
{"title":"The Research of the Digital Beamforming Algorithm for Optimal Noise Reduction in a Cylindrical Antenna Array with Directive Radiators","authors":"Y. Nechaev, I. Peshkov, N. Fortunova, I. Zaitseva","doi":"10.1109/SYNCHROINFO49631.2020.9166036","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166036","url":null,"abstract":"At present, digital antenna arrays are of growing research interest, since they allow us to form nulls and maxima of the radiation pattern without involving additional devices, but in the processing unit. This paper studies digital beamforming in three-dimensional space, i.e., in azimuth and angle of elevation on the example of a statistically optimal noise reduction algorithm in the channels of the array. A matrix-vector expression was obtained for calculating the vector of weight coefficients in a digital antenna array. The results of modeling a cylindrical antenna array of directive radiators are presented. The characteristics of a cylindrical digital antenna array are studied depending on the SNR (signal-to-noise ratio) for antenna elements with different directivity, and depending on the directive gain of antenna elements. The characteristics of digital beamforming, such as peak power, side lobe level, null depth, antenna gain, and others, were evaluated.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128044637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166108
A. B. Silantyev, A. Golubev, C. Fernandu, J. Olim, A. Timoshenko
In this paper we consider a surveillance radar using a multi-scanning observation method based on the well-known “track-before-detect” procedure. We analyse different approaches to estimating efficiency of long-term multi-scanning observation methods. The expected benefit of the methods is usually associated with detection range of radar. Detection range is increased due to long-term accumulation of signal energy. But it is necessary to consider not only detection range gain, but also the benefit related to obtaining of track data. We analyse the accuracy of trajectory parameters estimation and increase in tracks initiation range.
{"title":"Analysis of Efficiency of Long-Term Multi-Scanning Radar Observation Methods","authors":"A. B. Silantyev, A. Golubev, C. Fernandu, J. Olim, A. Timoshenko","doi":"10.1109/SYNCHROINFO49631.2020.9166108","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166108","url":null,"abstract":"In this paper we consider a surveillance radar using a multi-scanning observation method based on the well-known “track-before-detect” procedure. We analyse different approaches to estimating efficiency of long-term multi-scanning observation methods. The expected benefit of the methods is usually associated with detection range of radar. Detection range is increased due to long-term accumulation of signal energy. But it is necessary to consider not only detection range gain, but also the benefit related to obtaining of track data. We analyse the accuracy of trajectory parameters estimation and increase in tracks initiation range.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134367840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166068
N. E. Poborchaya
The article discusses the algorithm for the joint estimation of the stationary channel factors and signal distortions, such as DC drift, the frequency shift remaining from the demodulation procedure, amplitude and phase imbalance (IQ-imbalance). The problem of estimating unknown parameters is solved in two stages, by combining two procedures. The first, based on the polynomial approximation of the generalized communication channel and the linear least squares (MLS) method, estimates the constant components of the signal quadrature, amplitude and phase imbalance, as well as a rough estimate of the channel frequency and factors. The second procedure is synthesized using the Taylor approximation, a modified method of least squares in the form of a functional A.N. Tikhonov and regularization method. It is a nonlinear recursive algorithm for obtaining a more accurate estimate of the frequency and channel factors. This approach allows a sufficiently high estimation accuracy to reduce the complexity of the algorithm compared to using only the second procedure. The resulting algorithm works under conditions of uncorrelated Rayleigh fading in MIMO systems with spatial multiplexing with a priori uncertainty regarding the statistical characteristics of the communication channel (except for the dispersion of additive noise) and the laws of noise distribution, both phase and additive.
{"title":"Stationary Channel Factors and Signal Disturbances in a Direct Converter Receiver in a System with MIMO Joint Estimation Algorithm","authors":"N. E. Poborchaya","doi":"10.1109/SYNCHROINFO49631.2020.9166068","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166068","url":null,"abstract":"The article discusses the algorithm for the joint estimation of the stationary channel factors and signal distortions, such as DC drift, the frequency shift remaining from the demodulation procedure, amplitude and phase imbalance (IQ-imbalance). The problem of estimating unknown parameters is solved in two stages, by combining two procedures. The first, based on the polynomial approximation of the generalized communication channel and the linear least squares (MLS) method, estimates the constant components of the signal quadrature, amplitude and phase imbalance, as well as a rough estimate of the channel frequency and factors. The second procedure is synthesized using the Taylor approximation, a modified method of least squares in the form of a functional A.N. Tikhonov and regularization method. It is a nonlinear recursive algorithm for obtaining a more accurate estimate of the frequency and channel factors. This approach allows a sufficiently high estimation accuracy to reduce the complexity of the algorithm compared to using only the second procedure. The resulting algorithm works under conditions of uncorrelated Rayleigh fading in MIMO systems with spatial multiplexing with a priori uncertainty regarding the statistical characteristics of the communication channel (except for the dispersion of additive noise) and the laws of noise distribution, both phase and additive.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115341442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166086
A. Skuridin, A. Yelizarov, E. Zakirova, A. Tuv, V. T. Peresadov
In this paper we present a radio frequency precision sensor on rectangular spirals with the opposite direction of winding. The sensor is purposed to control and measure the gap to a flat metal surface. The sensor model was created using CST Studio Suite software. Using this model, we obtained relation between the gap width and change of electrodynamic parameters of the sensor. A schematic diagram of the sensor's measuring generator based on a modification of the Colpitts LC-generator was developed, and its characteristics were obtained in the PSpice. This paper also indicates the advantages of using proposed sensor as a base for various devices and systems for monitoring, measurement and controlling of physical quantities and parameters of technological processes.
本文提出了一种绕向相反的矩形螺旋上的射频精密传感器。该传感器用于控制和测量到平坦金属表面的间隙。传感器模型是使用CST Studio Suite软件创建的。利用该模型，得到了间隙宽度与传感器电动力参数变化的关系。基于对Colpitts LC-generator的改进，设计了传感器测量generator的原理图，并在PSpice中获得了其特性。本文还指出了将所提出的传感器作为各种设备和系统的基础，用于监测、测量和控制工艺过程的物理量和参数的优点。
{"title":"Precision Gap Sensor on Coupled Rectangular Spirals","authors":"A. Skuridin, A. Yelizarov, E. Zakirova, A. Tuv, V. T. Peresadov","doi":"10.1109/SYNCHROINFO49631.2020.9166086","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166086","url":null,"abstract":"In this paper we present a radio frequency precision sensor on rectangular spirals with the opposite direction of winding. The sensor is purposed to control and measure the gap to a flat metal surface. The sensor model was created using CST Studio Suite software. Using this model, we obtained relation between the gap width and change of electrodynamic parameters of the sensor. A schematic diagram of the sensor's measuring generator based on a modification of the Colpitts LC-generator was developed, and its characteristics were obtained in the PSpice. This paper also indicates the advantages of using proposed sensor as a base for various devices and systems for monitoring, measurement and controlling of physical quantities and parameters of technological processes.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123507252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166101
Z. R. Idiatullov, M. M. Fatykhov, G. Il'in, V. I. Il’in
The paper studies the behavior of the instantaneous frequency of a multi-position amplitude-phase-manipulated signal at the output of linear selective systems under conditions of strong intersymbol interference. On the basis of the used model, an analytical expression is obtained, which makes it possible to estimate the frequency changing of this type of signal at the output of linear selective systems. The result of the analysis of the obtained expression by means of mathematical simulating identified common properties that, in particular, can be used to create highly efficient symbolic synchronization systems, which can be used both in data transmission systems operating under strong intersymbol interference.
{"title":"On the Peculiarities of The Behaviour Of The Instantaneous Frequency of APSK-N-Signal At The Linear Selective System Output In The Presence Of ISI","authors":"Z. R. Idiatullov, M. M. Fatykhov, G. Il'in, V. I. Il’in","doi":"10.1109/SYNCHROINFO49631.2020.9166101","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166101","url":null,"abstract":"The paper studies the behavior of the instantaneous frequency of a multi-position amplitude-phase-manipulated signal at the output of linear selective systems under conditions of strong intersymbol interference. On the basis of the used model, an analytical expression is obtained, which makes it possible to estimate the frequency changing of this type of signal at the output of linear selective systems. The result of the analysis of the obtained expression by means of mathematical simulating identified common properties that, in particular, can be used to create highly efficient symbolic synchronization systems, which can be used both in data transmission systems operating under strong intersymbol interference.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123677938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/synchroinfo49631.2020.9166093
{"title":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (Synchroinfo) - Copyright notice","authors":"","doi":"10.1109/synchroinfo49631.2020.9166093","DOIUrl":"https://doi.org/10.1109/synchroinfo49631.2020.9166093","url":null,"abstract":"","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"120 23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126317341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166047
S. Loginov, M. Zuev, Ya. G. Agacheva, O. A. Sivintseva
This paper presents the modeling results OFDM system with use chaotic scrambling of signal constellation. In this paper statistical characteristics, the bit error rate (BER) and Peak to Average Power Ratio the signals in the system are estimated. The correlation coefficient between adjacent pairs of chaotic permutation vectors as a assessing the ability to withstand a statistical attack is estimated. The scrambling degree (SD) is evaluated. The results can be used in the design of modern communication systems in order to increase the security of transmitted information.
{"title":"Information Scrambling by Lorenz System Based Sequences in OFDM","authors":"S. Loginov, M. Zuev, Ya. G. Agacheva, O. A. Sivintseva","doi":"10.1109/SYNCHROINFO49631.2020.9166047","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166047","url":null,"abstract":"This paper presents the modeling results OFDM system with use chaotic scrambling of signal constellation. In this paper statistical characteristics, the bit error rate (BER) and Peak to Average Power Ratio the signals in the system are estimated. The correlation coefficient between adjacent pairs of chaotic permutation vectors as a assessing the ability to withstand a statistical attack is estimated. The scrambling degree (SD) is evaluated. The results can be used in the design of modern communication systems in order to increase the security of transmitted information.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129779518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166000
V. E. Dementyiev, N. Andriyanov, K. K. Vasilyiev
The article proposes methods for increasing the efficiency of pattern recognition in images using convolutional neural networks in conditions of insufficient reference images. It is proposed to use various kinds of image transformations to generate new images and increase the training sample volume. In particular, methods of scaling, adding noise, blurring, etc. are proposed. In addition to standard image transformations, it is supposed to increase the database by presenting patterns using a doubly stochastic model. In addition, the need for the use of regularization in training is noted. The recognition results are compared for two convolutional neural networks that differ only in the number of neurons for different initial data. It is shown that the highest recognition accuracy is provided by a network trained on a large number of augmentations in combination with images generated by a doubly stochastic model.
{"title":"Use of Images Augmentation and Implementation of Doubly Stochastic Models for Improving Accuracy of Recognition Algorithms Based on Convolutional Neural Networks","authors":"V. E. Dementyiev, N. Andriyanov, K. K. Vasilyiev","doi":"10.1109/SYNCHROINFO49631.2020.9166000","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166000","url":null,"abstract":"The article proposes methods for increasing the efficiency of pattern recognition in images using convolutional neural networks in conditions of insufficient reference images. It is proposed to use various kinds of image transformations to generate new images and increase the training sample volume. In particular, methods of scaling, adding noise, blurring, etc. are proposed. In addition to standard image transformations, it is supposed to increase the database by presenting patterns using a doubly stochastic model. In addition, the need for the use of regularization in training is noted. The recognition results are compared for two convolutional neural networks that differ only in the number of neurons for different initial data. It is shown that the highest recognition accuracy is provided by a network trained on a large number of augmentations in combination with images generated by a doubly stochastic model.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130845926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166125
B. Khlopov, N. P. Kolesnikov, G. Andreev, V. Shashurin, S. Meshkov
Research of multiferroid materials was conducted for the purpose of their possible use in industrial production for radio-electronic information devices [1]. It is shown that ordered structures based on silica microspheres with embedded magnetic nanoparticles represent one of the most interesting options for implementing multiferroid materials in the form of a 3D lattice of nanoclusters of crystalline multiferroics (iron, manganese and cobalt titanates of the FeTi205, FeTiO3 type), the results of which are presented in the materials of the article [2]. The possibility of the existence of a negative real part of the magnetic permeability of such materials under magnetic resonance conditions is not in doubt. Experiments conducted by a group of authors have shown that external fields can significantly change the characteristics of this class of nanomaterials [3]–[5] and allow them to be used in promising REA developments. Synthesis of multiferroic and multiferroic materials based on previously developed technologies to produce high-quality lattice packings of nanospheres of silica structure of opal SiT2 [6], and study of electromagnetic, dielectric, optical, magnetic and other properties of such materials is of great importance due to the prospects of their application, for example, allowed to find out the conditions under which this class of multiferroic media can be used in the creation of an effective electronic information devices that control electromagnetic fields.
{"title":"The Possibility and Prospects for Using Multiferroic Materials in the Production","authors":"B. Khlopov, N. P. Kolesnikov, G. Andreev, V. Shashurin, S. Meshkov","doi":"10.1109/SYNCHROINFO49631.2020.9166125","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166125","url":null,"abstract":"Research of multiferroid materials was conducted for the purpose of their possible use in industrial production for radio-electronic information devices [1]. It is shown that ordered structures based on silica microspheres with embedded magnetic nanoparticles represent one of the most interesting options for implementing multiferroid materials in the form of a 3D lattice of nanoclusters of crystalline multiferroics (iron, manganese and cobalt titanates of the FeTi205, FeTiO3 type), the results of which are presented in the materials of the article [2]. The possibility of the existence of a negative real part of the magnetic permeability of such materials under magnetic resonance conditions is not in doubt. Experiments conducted by a group of authors have shown that external fields can significantly change the characteristics of this class of nanomaterials [3]–[5] and allow them to be used in promising REA developments. Synthesis of multiferroic and multiferroic materials based on previously developed technologies to produce high-quality lattice packings of nanospheres of silica structure of opal SiT2 [6], and study of electromagnetic, dielectric, optical, magnetic and other properties of such materials is of great importance due to the prospects of their application, for example, allowed to find out the conditions under which this class of multiferroic media can be used in the creation of an effective electronic information devices that control electromagnetic fields.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131114371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166070
S. S. Pechnikov, S. A. Sherstukov
The article describes a method for optimizing the structure of spectrally effective radio signals using functional converters and vector modulators as part of the predistortion path, which allows you to convert the temporal forms of amplitude-phase-modulated signals to radio signals with a constant envelope to increase energy efficiency through the use of nonlinear power amplifiers.
{"title":"Optimization of the Structure of Spectral-Effective Radio Signals on the Basis of Functional Converters and Vector Modulators in the Composition of the Predistortion Tract","authors":"S. S. Pechnikov, S. A. Sherstukov","doi":"10.1109/SYNCHROINFO49631.2020.9166070","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166070","url":null,"abstract":"The article describes a method for optimizing the structure of spectrally effective radio signals using functional converters and vector modulators as part of the predistortion path, which allows you to convert the temporal forms of amplitude-phase-modulated signals to radio signals with a constant envelope to increase energy efficiency through the use of nonlinear power amplifiers.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116463074","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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