Pub Date : 2019-06-01DOI: 10.1109/RSEMW.2019.8792733
V. Kaloshin, N. T. Le
A study was made of the radiation and scattering characteristics of a new class of antenna arrays — Over Wave Region (with a frequency band of more than 10: 1). A flat one polarization array of TEM horns and a two polarization one of conductors of variable square section are considered. The results of numerical simulation of the two polarization array using the finite element method showed that in the case of in-phase radiation and scanning in sector 90° in the H plane its matching band is more than 30:1. For scanning sector 90° in the E plane the matching band is more than 20:1. In the case of normal incidence the monostatic RCS of the two polarization array is less than the one of the waveguide array by 10-30 dB in the frequency band of more than 10:1. It is close to the RCS of the TEM horns array for one of the linear polarizations. The RCS of the TEM horns array is close to the RCS of the waveguide array for the orthogonal polarization. With increasing angles of incidence the difference in monostatic RCS arrays decreases. A study of bistatic RCS was also conducted.
{"title":"Over Wave Region Antenna Arrays: Radiation and Scattering Characteristics","authors":"V. Kaloshin, N. T. Le","doi":"10.1109/RSEMW.2019.8792733","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792733","url":null,"abstract":"A study was made of the radiation and scattering characteristics of a new class of antenna arrays — Over Wave Region (with a frequency band of more than 10: 1). A flat one polarization array of TEM horns and a two polarization one of conductors of variable square section are considered. The results of numerical simulation of the two polarization array using the finite element method showed that in the case of in-phase radiation and scanning in sector 90° in the H plane its matching band is more than 30:1. For scanning sector 90° in the E plane the matching band is more than 20:1. In the case of normal incidence the monostatic RCS of the two polarization array is less than the one of the waveguide array by 10-30 dB in the frequency band of more than 10:1. It is close to the RCS of the TEM horns array for one of the linear polarizations. The RCS of the TEM horns array is close to the RCS of the waveguide array for the orthogonal polarization. With increasing angles of incidence the difference in monostatic RCS arrays decreases. A study of bistatic RCS was also conducted.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121882266","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792796
L. Cherckesova, D. Bezuglov, V. Porksheyan, I. Smirnov, G. P. Sinyavskiy, B. Akishin
In the offered examination the mathematical modelling of interaction processes of electromagnetic waves with composite substances nanostructures and electrodynamic structures on the base of graphene and carbon nanotubes is made. Models are grounded on solution of diffraction boundary–value 3D problems for Maxwell’s equations with electrodynamic boundary conditions. Principles of subTHz and THz frequency bands controlled arrangements construction – filters, modulators, polarizers, etc., on the base of nanostructures by type «graphene – dielectric», lattices by type «carbon nanotube–graphene», graphene metasurfaces, etc., and also nonlinear parametric zonal transducers – amplifiers and generators on the base of graphene nanostructures are researched. Creation of radioelectronic instrumentation and equipment of new generation, capable to work in subTHz and THz frequency bands, will cause the rapid development of informational telecommunications of XXI–st century.
{"title":"Mathematic Modelling of Nonlinear Parametric Zonal Transducers of SubTHz and THz Bands on the Base of Graphene and Carbon Nanotubes","authors":"L. Cherckesova, D. Bezuglov, V. Porksheyan, I. Smirnov, G. P. Sinyavskiy, B. Akishin","doi":"10.1109/RSEMW.2019.8792796","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792796","url":null,"abstract":"In the offered examination the mathematical modelling of interaction processes of electromagnetic waves with composite substances nanostructures and electrodynamic structures on the base of graphene and carbon nanotubes is made. Models are grounded on solution of diffraction boundary–value 3D problems for Maxwell’s equations with electrodynamic boundary conditions. Principles of subTHz and THz frequency bands controlled arrangements construction – filters, modulators, polarizers, etc., on the base of nanostructures by type «graphene – dielectric», lattices by type «carbon nanotube–graphene», graphene metasurfaces, etc., and also nonlinear parametric zonal transducers – amplifiers and generators on the base of graphene nanostructures are researched. Creation of radioelectronic instrumentation and equipment of new generation, capable to work in subTHz and THz frequency bands, will cause the rapid development of informational telecommunications of XXI–st century.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117014380","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792764
Nadezhda G. Kotonaeva, I. V. Romanov, P. V. Nikolaev, E. N. Khotenko
the idea and the first results of experiments on the registration of the critical frequency of layer F2 in the Earth's ionosphere with an interval of one minute to determine the coefficient of minute unsteadiness of the ionosphere and its dependence on time are presented. The ionosonde used for the experiment, its main characteristics, advantages and disadvantages are described. The scientific and applied significance of the experiment is discussed.
{"title":"Registration of Minute Changes in the Critical Frequency of the F2 Layer by the Ionosonde of Vertical Radio Sounding","authors":"Nadezhda G. Kotonaeva, I. V. Romanov, P. V. Nikolaev, E. N. Khotenko","doi":"10.1109/RSEMW.2019.8792764","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792764","url":null,"abstract":"the idea and the first results of experiments on the registration of the critical frequency of layer F2 in the Earth's ionosphere with an interval of one minute to determine the coefficient of minute unsteadiness of the ionosphere and its dependence on time are presented. The ionosonde used for the experiment, its main characteristics, advantages and disadvantages are described. The scientific and applied significance of the experiment is discussed.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"01 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130653417","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792736
I. Malyshev, E. V. Nikolaev
The purpose of the research carried out in this work was the development model of filtering band-barrier properties of conducting composite (meta-material) structures consisting of two concentric strip rings having cuts in diametrically opposite directions and possible combinations thereof in the form of several similar elements. Calculated and experimental studies were carried out on the example of the coplanar transmission line section in which these filtering structures are placed on the reverse side of the conducting section. As a result, it was revealed that the double split ring resonators are an effective strip-barrier composite structure for coplanar, strip line and the like transmission lines. All the results of the calculation and CAD modeling were experimentally tested on the mock-ups made (layouts). New practical possibilities were found for tuning the resonant frequency of these structures (in the range of about 50%) by rotating the proposed designs of mobile modules with split rings. They can be placed under the conductive line in a convenient place for installation. The methods of resonant frequency tuning and fine tuning of the bandwidth and the transmission factor are described in the configuration of working models [1]–[11].
{"title":"Inclusion of Concentric Ring Split Structures in the Microwave Transmission Lines to Control their Conductive Properties","authors":"I. Malyshev, E. V. Nikolaev","doi":"10.1109/RSEMW.2019.8792736","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792736","url":null,"abstract":"The purpose of the research carried out in this work was the development model of filtering band-barrier properties of conducting composite (meta-material) structures consisting of two concentric strip rings having cuts in diametrically opposite directions and possible combinations thereof in the form of several similar elements. Calculated and experimental studies were carried out on the example of the coplanar transmission line section in which these filtering structures are placed on the reverse side of the conducting section. As a result, it was revealed that the double split ring resonators are an effective strip-barrier composite structure for coplanar, strip line and the like transmission lines. All the results of the calculation and CAD modeling were experimentally tested on the mock-ups made (layouts). New practical possibilities were found for tuning the resonant frequency of these structures (in the range of about 50%) by rotating the proposed designs of mobile modules with split rings. They can be placed under the conductive line in a convenient place for installation. The methods of resonant frequency tuning and fine tuning of the bandwidth and the transmission factor are described in the configuration of working models [1]–[11].","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123992567","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792783
A. Bobreshov, A. S. Zhabin, V. A. Stepkin, G. K. Uskov
a high-performance ultra-short pulse generator based on a step recovery diode (SRD) has been proposed in the paper. The generator circuit solution utilizes the selection of a mode of operation, the optimization of passive component values and the back edge shaper to generate the output pulse signal with the high amplitude and the short width. According to the measurement results the pulse signal amplitude is 70V, the width is 230ps and the ringing level is -23.5dB. This performance has significant potential in applications where operating in thick and lossy medium is concerned.
{"title":"Ultra-short Pulse Generator with Back Edge Shaper","authors":"A. Bobreshov, A. S. Zhabin, V. A. Stepkin, G. K. Uskov","doi":"10.1109/RSEMW.2019.8792783","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792783","url":null,"abstract":"a high-performance ultra-short pulse generator based on a step recovery diode (SRD) has been proposed in the paper. The generator circuit solution utilizes the selection of a mode of operation, the optimization of passive component values and the back edge shaper to generate the output pulse signal with the high amplitude and the short width. According to the measurement results the pulse signal amplitude is 70V, the width is 230ps and the ringing level is -23.5dB. This performance has significant potential in applications where operating in thick and lossy medium is concerned.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114170565","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792721
V. Zakharchenko
The work introduces the notion of a sine of the angle between two finite signals. This enables use of nonharmonic signals of finite duration for estimation of the dielectric loss angle tangent in reactive two-terminal devices. Block diagrams of small loss measurement devices are analyzed. Results of mathematical modelling are presented for a two-terminal device. The device is modelling a piezoceramic resonator. It’s shown the correlation method of measuring by using orthogonal signals leads to increase the productivity of control of the objects during piezoceramic with high quality production.
{"title":"Signal Processing in Small Dielectric Loss Measurements in Piezoceramic Resonators","authors":"V. Zakharchenko","doi":"10.1109/RSEMW.2019.8792721","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792721","url":null,"abstract":"The work introduces the notion of a sine of the angle between two finite signals. This enables use of nonharmonic signals of finite duration for estimation of the dielectric loss angle tangent in reactive two-terminal devices. Block diagrams of small loss measurement devices are analyzed. Results of mathematical modelling are presented for a two-terminal device. The device is modelling a piezoceramic resonator. It’s shown the correlation method of measuring by using orthogonal signals leads to increase the productivity of control of the objects during piezoceramic with high quality production.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116250751","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792789
Y. Yukhanov, T. Privalova, E. V. Kriuk
The two-dimensional problem of the diffraction of a plane E-polarized wave on a Van Atta waveguide array located on the surface of a perfectly-conducting circular cylinder is solved. The radiators in the form of open ends of waveguides are connected by plane-parallel multimode waveguides of uniform length. The task is reduced to solving an integral equation for the magnetic field vector over the entire surface of the cylinder, which is reduced to an infinite system of linear algebraic equations for the coefficients of the expansion of the magnetic field vector for a complex Fourier series in azimuthal harmonics. The solution of the equation was received strictly and approximately. An expression for the scattering diagram is obtained, represented through the geometrical parameters of the structure.
{"title":"Diffraction of a Plane E-polarized Wave on Waveguide Van Atta Array, Placed on the Surface of PEC Cylinder","authors":"Y. Yukhanov, T. Privalova, E. V. Kriuk","doi":"10.1109/RSEMW.2019.8792789","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792789","url":null,"abstract":"The two-dimensional problem of the diffraction of a plane E-polarized wave on a Van Atta waveguide array located on the surface of a perfectly-conducting circular cylinder is solved. The radiators in the form of open ends of waveguides are connected by plane-parallel multimode waveguides of uniform length. The task is reduced to solving an integral equation for the magnetic field vector over the entire surface of the cylinder, which is reduced to an infinite system of linear algebraic equations for the coefficients of the expansion of the magnetic field vector for a complex Fourier series in azimuthal harmonics. The solution of the equation was received strictly and approximately. An expression for the scattering diagram is obtained, represented through the geometrical parameters of the structure.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113965389","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792801
Y. Parshin, M. Grachev
The problem of the direction determination to the radio radiation source under the action of spatially correlated interferences is solving. Algorithms for the optimal angular coordinate estimation for the deterministic signal, the quasi-deterministic signal, and the random Gaussian signal are considered. The error of the direction determination to the radio radiation source is calculated on basis of the Cramer-Rao bound as applied to the signal-interfering situation under consideration for a few receiving channel. Spatial interference cancellation is carried out taking into account the effect of the mutual coupling of spatial channels and circuit noise. A changing in the matrix of mutual impedances of the antenna system leads to their mismatch with the load impedances. A problem of impedance matching depends on the signal-interfering situation has been solved. The gain in the accuracy of maximum likelihood estimation the angular coordinates obtained with optimal matching is calculated.
{"title":"Efficiency of the Angular Coordinate Estimation under the Action of Spatially Correlated Interferences and Mutual Influence of Spatial Channels","authors":"Y. Parshin, M. Grachev","doi":"10.1109/RSEMW.2019.8792801","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792801","url":null,"abstract":"The problem of the direction determination to the radio radiation source under the action of spatially correlated interferences is solving. Algorithms for the optimal angular coordinate estimation for the deterministic signal, the quasi-deterministic signal, and the random Gaussian signal are considered. The error of the direction determination to the radio radiation source is calculated on basis of the Cramer-Rao bound as applied to the signal-interfering situation under consideration for a few receiving channel. Spatial interference cancellation is carried out taking into account the effect of the mutual coupling of spatial channels and circuit noise. A changing in the matrix of mutual impedances of the antenna system leads to their mismatch with the load impedances. A problem of impedance matching depends on the signal-interfering situation has been solved. The gain in the accuracy of maximum likelihood estimation the angular coordinates obtained with optimal matching is calculated.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128010497","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792788
Nikolay Boldirikhin, O. Safaryan, A. Svizhenko
Currently, within the framework of the classical theory of observation management, approaches to the issues of optimal control of measurement processes in information systems are well developed. The use of linear filtering algorithms in problems of estimating information processes will make it possible to plan observations prior to measurements based on a priori models state and observation. However, in the classical theory of management of observations, it is assumed that the time of the appearance and disappearance of information processes is known in advance, on the basis of this and the plan of observations is built. However, in practice, real points in time of the appearance and disappearance of information processes may differ significantly from the calculated values. Therefore, research to take into account the random nature of the emergence and disappearance of information processes is relevant. When using linear filtering, you can get averaged a priori plan of observations. However, in a real situation, such a plan needs to be adjusted directly in the observation process.This article is devoted to the practical application of the results of a priori planning of observations on the example of a pulsed information system when observing the flow of processes appearing at random points in time.As a result of research conducted in the article, the possibility of obtaining a significant gain in accuracy (compared to a uniform tracking mode) when filtering information processes in pulse information systems has been revealed.
{"title":"Control of Observations in Pulse Information Systems","authors":"Nikolay Boldirikhin, O. Safaryan, A. Svizhenko","doi":"10.1109/RSEMW.2019.8792788","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792788","url":null,"abstract":"Currently, within the framework of the classical theory of observation management, approaches to the issues of optimal control of measurement processes in information systems are well developed. The use of linear filtering algorithms in problems of estimating information processes will make it possible to plan observations prior to measurements based on a priori models state and observation. However, in the classical theory of management of observations, it is assumed that the time of the appearance and disappearance of information processes is known in advance, on the basis of this and the plan of observations is built. However, in practice, real points in time of the appearance and disappearance of information processes may differ significantly from the calculated values. Therefore, research to take into account the random nature of the emergence and disappearance of information processes is relevant. When using linear filtering, you can get averaged a priori plan of observations. However, in a real situation, such a plan needs to be adjusted directly in the observation process.This article is devoted to the practical application of the results of a priori planning of observations on the example of a pulsed information system when observing the flow of processes appearing at random points in time.As a result of research conducted in the article, the possibility of obtaining a significant gain in accuracy (compared to a uniform tracking mode) when filtering information processes in pulse information systems has been revealed.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130238028","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 : 2019-06-01DOI: 10.1109/RSEMW.2019.8792810
K. Kobrin, V. Rudakov, V. Sledkov, Liu Zimeng, M. Manuilov
A novel design of diplexer for mobile base stations operating within frequency bands 690-862/880-960 MHz is proposed. The use of diplexers allows to implement the simultaneous operation of wideband antenna array within two frequency bands. Suggested diplexer design is based on interdigital filters and coaxial power divider. Full wave analysis and optimization of diplexer is carried out by finite element method implemented in Ansys HFSS. Calculated VSWR is equal to 1.2 within operational bands. The sample of diplexer has been manufactured and successfully tested, the measured and calculated results are in good agreement.
{"title":"A Novel Design of Wideband Diplexer for Base Station Applications","authors":"K. Kobrin, V. Rudakov, V. Sledkov, Liu Zimeng, M. Manuilov","doi":"10.1109/RSEMW.2019.8792810","DOIUrl":"https://doi.org/10.1109/RSEMW.2019.8792810","url":null,"abstract":"A novel design of diplexer for mobile base stations operating within frequency bands 690-862/880-960 MHz is proposed. The use of diplexers allows to implement the simultaneous operation of wideband antenna array within two frequency bands. Suggested diplexer design is based on interdigital filters and coaxial power divider. Full wave analysis and optimization of diplexer is carried out by finite element method implemented in Ansys HFSS. Calculated VSWR is equal to 1.2 within operational bands. The sample of diplexer has been manufactured and successfully tested, the measured and calculated results are in good agreement.","PeriodicalId":158616,"journal":{"name":"2019 Radiation and Scattering of Electromagnetic Waves (RSEMW)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134080675","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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