Pub Date : 2020-07-01DOI: 10.1109/SYNCHROINFO49631.2020.9166064
V. Magsumov, V. Priputin, D. S. Chirov
Currently, the electronic environment is largely determined by the use of modern radio communication systems with adaptive modes of operation, as well as the use of complex broadband signals. Monitoring a wide frequency range is used when observing various energy and spectral parameters of radio signals. The applicability of a particular signal format to the problem being solved is determined by the correspondence of these parameters to the conditions in which information is transmitted and received. The aforementioned parameters include possible interference, leading to various kinds of distortions, which, in turn, cause a deterioration in the parameters of radio monitoring systems. One of the possible methods for solving the problem of processing a wide frequency range in a difficult interference environment is the use of adaptive subband filtering based on a hybrid filter bank. The basis of the method is the decomposition of the input signal into individual frequency components (subchannels), the processing of which is performed at a speed M reduced by a factor of compared with the input signal. Further, the processed frequency components are combined into a single signal. A test of the developed filter bank was carried out on a processor with an arm core.
{"title":"Development and Research of a HF Range Hybrid Filter Bank Based on ARM Processor","authors":"V. Magsumov, V. Priputin, D. S. Chirov","doi":"10.1109/SYNCHROINFO49631.2020.9166064","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166064","url":null,"abstract":"Currently, the electronic environment is largely determined by the use of modern radio communication systems with adaptive modes of operation, as well as the use of complex broadband signals. Monitoring a wide frequency range is used when observing various energy and spectral parameters of radio signals. The applicability of a particular signal format to the problem being solved is determined by the correspondence of these parameters to the conditions in which information is transmitted and received. The aforementioned parameters include possible interference, leading to various kinds of distortions, which, in turn, cause a deterioration in the parameters of radio monitoring systems. One of the possible methods for solving the problem of processing a wide frequency range in a difficult interference environment is the use of adaptive subband filtering based on a hybrid filter bank. The basis of the method is the decomposition of the input signal into individual frequency components (subchannels), the processing of which is performed at a speed M reduced by a factor of compared with the input signal. Further, the processed frequency components are combined into a single signal. A test of the developed filter bank was carried out on a processor with an arm core.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"5 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":"117351228","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/SYNCHROINFO49631.2020.9166084
D. Ravshanov, D. Letavin, I. A. Terebov
A Butler matrix scheme with the possibility of forming four independent radiation patterns is proposed. The dimensions of the circuit under consideration were reduced due to the miniaturization of all directional couplers included in the matrix. The dimensions of the couplers were reduced using artificial transmission lines - this allowed to reduce the matrix area by 73.15% relative to the matrix in the standard version. Theoretical and experimental characteristics are given, according to which it was established that the operating frequency band of the compact matrix is already 10%. The proposed matrix can be easily manufactured using standard methods for the manufacture of printed circuit boards.
{"title":"Butler Matrix 4x4 Ultra High Frequency","authors":"D. Ravshanov, D. Letavin, I. A. Terebov","doi":"10.1109/SYNCHROINFO49631.2020.9166084","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166084","url":null,"abstract":"A Butler matrix scheme with the possibility of forming four independent radiation patterns is proposed. The dimensions of the circuit under consideration were reduced due to the miniaturization of all directional couplers included in the matrix. The dimensions of the couplers were reduced using artificial transmission lines - this allowed to reduce the matrix area by 73.15% relative to the matrix in the standard version. Theoretical and experimental characteristics are given, according to which it was established that the operating frequency band of the compact matrix is already 10%. The proposed matrix can be easily manufactured using standard methods for the manufacture of printed circuit boards.","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":"129036134","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/SYNCHROINFO49631.2020.9166066
R. Eshpay, O. A. Stepustchenko, I. U. Kurbiev, A. D. Proskuriakov, V. V. Kadushkin
The paper presents the results of designing a data collection system aimed to prevent pressure sores and ulcers in immobile patients, most of the time are in a wheelchair. Three variants of sensor part of system are discussed. In all variants, two similar linearly chirped fiber Bragg gratings (LC-FBG) are used forming one system sensor: first for patient pressure sensing, second for temperature compensation. In first variant, we used classical LC-FBG. In second one, both gratings in center had one phase $pi$-shift. The use of such gratings will reduce the cost of the spectral interrogation system, which limits the use of similar fiber-optic systems in medical practice. The interrogation system used for these type sensors belongs to microwave photonics class. In third variant, the second pressure sensor based on address LC-FBG with two phase $pi$-shifts were utilized. The use of such type sensors will solve the problems of addressing the information received from specific wheelchair zones connected with right and left shoulder blades, buttocks and heels.
{"title":"LC-FBG Based Microwave Photonic System for Wheelchair Patient Pose Monitoring","authors":"R. Eshpay, O. A. Stepustchenko, I. U. Kurbiev, A. D. Proskuriakov, V. V. Kadushkin","doi":"10.1109/SYNCHROINFO49631.2020.9166066","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166066","url":null,"abstract":"The paper presents the results of designing a data collection system aimed to prevent pressure sores and ulcers in immobile patients, most of the time are in a wheelchair. Three variants of sensor part of system are discussed. In all variants, two similar linearly chirped fiber Bragg gratings (LC-FBG) are used forming one system sensor: first for patient pressure sensing, second for temperature compensation. In first variant, we used classical LC-FBG. In second one, both gratings in center had one phase $pi$-shift. The use of such gratings will reduce the cost of the spectral interrogation system, which limits the use of similar fiber-optic systems in medical practice. The interrogation system used for these type sensors belongs to microwave photonics class. In third variant, the second pressure sensor based on address LC-FBG with two phase $pi$-shifts were utilized. The use of such type sensors will solve the problems of addressing the information received from specific wheelchair zones connected with right and left shoulder blades, buttocks and heels.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"2004 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":"127331220","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/SYNCHROINFO49631.2020.9166131
M. V. Balashkov, V. M. Bogachev, I. N. Leonov
This paper is devoted to the criteria choice and determination of optimal operation modes and parameters of oscillating systems of double- and triple-circuit oscillators taking into account the contradictory requirements to the generating power, the frequency instability and the oscillation stability. The optimization algorithm is based on the maximum search of the objective function (OF) at the specified regeneration factor. As the objective function, we choose the function equaled to the product of the partial power of the first circuit and the frequency stabilization coefficient in the power $nu=1ldots 2$. At $nu=1$, the OF maximum corresponds to the maximum of the frequency stabilization coefficient; at $nu=2$-to the minimum of the phase diffusion coefficient. At intermediate $nu$ value, the compromise task solution is provided. At optimization, we choose the oscillating system locus shape, at which the hysteresis phenomena absence is provided at oscillator tuning on the nominal frequency. Recommendations on the efficiency choice of the load coupling circuit are discussed.
{"title":"Optimization in Oscillators and Autodynes with Stabilizing Resonators","authors":"M. V. Balashkov, V. M. Bogachev, I. N. Leonov","doi":"10.1109/SYNCHROINFO49631.2020.9166131","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166131","url":null,"abstract":"This paper is devoted to the criteria choice and determination of optimal operation modes and parameters of oscillating systems of double- and triple-circuit oscillators taking into account the contradictory requirements to the generating power, the frequency instability and the oscillation stability. The optimization algorithm is based on the maximum search of the objective function (OF) at the specified regeneration factor. As the objective function, we choose the function equaled to the product of the partial power of the first circuit and the frequency stabilization coefficient in the power $nu=1ldots 2$. At $nu=1$, the OF maximum corresponds to the maximum of the frequency stabilization coefficient; at $nu=2$-to the minimum of the phase diffusion coefficient. At intermediate $nu$ value, the compromise task solution is provided. At optimization, we choose the oscillating system locus shape, at which the hysteresis phenomena absence is provided at oscillator tuning on the nominal frequency. Recommendations on the efficiency choice of the load coupling circuit are discussed.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"39 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":"132214850","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/SYNCHROINFO49631.2020.9166114
I. Bogachkov, N. Gorlov
A classification of varieties of single-mode optical fibers based on analysis of the Mandelstam - Brillouin backscatter characteristics is discussed in this paper. It is shown how by the characteristics of the frequency profiles of the Mandelstam - Brillouin scattering spectrum, one can determine the type of fiber and also evaluate the change in the strain and Brillouin frequency shift. The programs for the automated processing of the Brillouin reflectograms data are presented. Based on the analysis of Brillouin reflectograms, it is possible to identify a factor that had a predominant influence on the characteristics of the Mandelstam - Brillouin backscatter signal in the explored sections of single-mode optical fibers.
{"title":"The Basics of Automated Processing of Optical Fiber Reflectograms for Evaluating Characteristics of the Mandelstam — Brillouin Backscatter","authors":"I. Bogachkov, N. Gorlov","doi":"10.1109/SYNCHROINFO49631.2020.9166114","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166114","url":null,"abstract":"A classification of varieties of single-mode optical fibers based on analysis of the Mandelstam - Brillouin backscatter characteristics is discussed in this paper. It is shown how by the characteristics of the frequency profiles of the Mandelstam - Brillouin scattering spectrum, one can determine the type of fiber and also evaluate the change in the strain and Brillouin frequency shift. The programs for the automated processing of the Brillouin reflectograms data are presented. Based on the analysis of Brillouin reflectograms, it is possible to identify a factor that had a predominant influence on the characteristics of the Mandelstam - Brillouin backscatter signal in the explored sections of single-mode optical fibers.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"12 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":"133494938","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/SYNCHROINFO49631.2020.9166031
E. O. Kandaurova, D. S. Chirov
Currently, systems with dynamic access to the radio spectrum technology, such as cognitive radio systems, are in demand and are actively developing. To ensure the effective operation of such systems, constant knowledge of the radio environment in the frequency range used is necessary. This article is devoted to the development of algorithms and software for intelligent analysis of the frequency spectrum to build a model for predicting the spectrum occupancy in time. The solution of this problem allows you to provide dynamic spectrum access without affecting the rights and quality of communication of primary users, while not reducing the quality of service for secondary users. This article has proposed and described an algorithm for implementing dynamic spectrum access with prediction based on spectrum occupancy models, consisting of 3 stages. Currently, software has been developed and a field experiment has been carried out to implement the first stage of the algorithm. The results of a field experiment for the first stage showed that the developed software allows us to identify free parts of the spectrum during the day. Also, the values of the duty cycle were obtained, allowing predicting the probability of occupancy of the frequency channel in the selected time period. Using this information, it is possible to build frequent (sequential) patterns to develop an up-to-date prediction model of spectrum occupancy.
{"title":"Algorithm and Software for Intelligent Analysis of the Frequency Spectrum for Cognitive Radio Systems","authors":"E. O. Kandaurova, D. S. Chirov","doi":"10.1109/SYNCHROINFO49631.2020.9166031","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166031","url":null,"abstract":"Currently, systems with dynamic access to the radio spectrum technology, such as cognitive radio systems, are in demand and are actively developing. To ensure the effective operation of such systems, constant knowledge of the radio environment in the frequency range used is necessary. This article is devoted to the development of algorithms and software for intelligent analysis of the frequency spectrum to build a model for predicting the spectrum occupancy in time. The solution of this problem allows you to provide dynamic spectrum access without affecting the rights and quality of communication of primary users, while not reducing the quality of service for secondary users. This article has proposed and described an algorithm for implementing dynamic spectrum access with prediction based on spectrum occupancy models, consisting of 3 stages. Currently, software has been developed and a field experiment has been carried out to implement the first stage of the algorithm. The results of a field experiment for the first stage showed that the developed software allows us to identify free parts of the spectrum during the day. Also, the values of the duty cycle were obtained, allowing predicting the probability of occupancy of the frequency channel in the selected time period. Using this information, it is possible to build frequent (sequential) patterns to develop an up-to-date prediction model of spectrum occupancy.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"11 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131614061","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/SYNCHROINFO49631.2020.9166069
D. Magomedova, O. Sheluhin
Methods and algorithms for embedding marked information with fractal properties to ensure the integrity and authenticity of raster images are considered. The features of using algebraic fractals as intermediate cover images, as well as secret keys that define places for embedding watermarks, are analyzed. Numerical examples show that the proposed methods increase the integrity and authenticity of bitmap images.
{"title":"Fractal Models and Algorithms for Creating a Protective Marking for Integrity and Authenticity Bitmap Images","authors":"D. Magomedova, O. Sheluhin","doi":"10.1109/SYNCHROINFO49631.2020.9166069","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166069","url":null,"abstract":"Methods and algorithms for embedding marked information with fractal properties to ensure the integrity and authenticity of raster images are considered. The features of using algebraic fractals as intermediate cover images, as well as secret keys that define places for embedding watermarks, are analyzed. Numerical examples show that the proposed methods increase the integrity and authenticity of bitmap images.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"12 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":"123926572","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/SYNCHROINFO49631.2020.9166042
A. S. Adzhemov, A. Y. Kudryashova
Modern infocommunication systems, combining the capabilities of computer technology and communication devices, almost always have a digital implementation using binary code. In this case, various code structures are used, which on the one hand provide high transmission efficiency of the initial messages, the required noise immunity and, as far as possible, simple practical implementation, which allows to achieve lower technical and financial costs, minimize delays, etc. Moreover, the question of how the solutions used differ from theoretically achievable potential boundaries is very important.
{"title":"About Interferable Binary Code Constructions","authors":"A. S. Adzhemov, A. Y. Kudryashova","doi":"10.1109/SYNCHROINFO49631.2020.9166042","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166042","url":null,"abstract":"Modern infocommunication systems, combining the capabilities of computer technology and communication devices, almost always have a digital implementation using binary code. In this case, various code structures are used, which on the one hand provide high transmission efficiency of the initial messages, the required noise immunity and, as far as possible, simple practical implementation, which allows to achieve lower technical and financial costs, minimize delays, etc. Moreover, the question of how the solutions used differ from theoretically achievable potential boundaries is very important.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"40 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":"115571622","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/SYNCHROINFO49631.2020.9166113
V. Kochemasov, V. Gevorkyan, S. Mikhalin, Yu. E. Soloukhin, A. Chenakin
Characteristics of microstrip microwave oscillator variants controlling by a voltage on a varactor diode are presented in the oscillating system, which is formed on the base of the open dielectric resonator. Our aim is the solution of the task to develop the voltage-controlled oscillator with a low level of phase noise spectral density for its application in devices with the analog phase-locked loop for frequency control.
{"title":"Microwave Voltage-Controlled Oscillators on the Base of Micro-Assembles with Dielectric Resonators","authors":"V. Kochemasov, V. Gevorkyan, S. Mikhalin, Yu. E. Soloukhin, A. Chenakin","doi":"10.1109/SYNCHROINFO49631.2020.9166113","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166113","url":null,"abstract":"Characteristics of microstrip microwave oscillator variants controlling by a voltage on a varactor diode are presented in the oscillating system, which is formed on the base of the open dielectric resonator. Our aim is the solution of the task to develop the voltage-controlled oscillator with a low level of phase noise spectral density for its application in devices with the analog phase-locked loop for frequency control.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"6 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":"126039272","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/SYNCHROINFO49631.2020.9166107
E. Sharapova
The work is devoted to the organization of the search index of the duplicate text detection systems Author.NET. The paper considers the structure of the search index. The search index can be divided into several groups of files - terms, documents, TF*IDF index, signatures, shingles. In the article the ways of organizing the search index are considered - index storage in RAM, compression of index file, tree index, index table of contents. It is given a proposal for organizing a search index for duplicate text detection system. During the experiments, it was found that the most profitable option is to use compressed index files stored on the SSD.
{"title":"Increase the Speed of Search Index in the Duplicate Text Detection Systems","authors":"E. Sharapova","doi":"10.1109/SYNCHROINFO49631.2020.9166107","DOIUrl":"https://doi.org/10.1109/SYNCHROINFO49631.2020.9166107","url":null,"abstract":"The work is devoted to the organization of the search index of the duplicate text detection systems Author.NET. The paper considers the structure of the search index. The search index can be divided into several groups of files - terms, documents, TF*IDF index, signatures, shingles. In the article the ways of organizing the search index are considered - index storage in RAM, compression of index file, tree index, index table of contents. It is given a proposal for organizing a search index for duplicate text detection system. During the experiments, it was found that the most profitable option is to use compressed index files stored on the SSD.","PeriodicalId":255578,"journal":{"name":"2020 Systems of Signal Synchronization, Generating and Processing in Telecommunications (SYNCHROINFO)","volume":"21 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":"123194057","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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