Pub Date : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637113
M. González-Huici, U. Uschkerat
Ground penetrating radar (GPR), which can detect shallow buried low dielectric contrast objects in a variety of soils by non-invasive subsurface sensing, is a promising technology for imaging low-metal or non-metallic landmines. In this paper we present a complete model of a complex GPR scenario which is solved via finite element method, and includes the actual impulse GPR system, interface, soil and targets. We obtain time domain signatures for different testmines and small objects under different soil conditions which are satisfactorily correlated with measurements. The simulated responses give us a broad understanding about the factors which control the electromagnetic scattering by small objects and are used to interpret the characteristics of the signatures according to the target and background parameters. These obtained waveforms may be applied to reduce the false alarm.
{"title":"GPR modeling for landmine detection","authors":"M. González-Huici, U. Uschkerat","doi":"10.1109/URSI-EMTS.2010.5637113","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637113","url":null,"abstract":"Ground penetrating radar (GPR), which can detect shallow buried low dielectric contrast objects in a variety of soils by non-invasive subsurface sensing, is a promising technology for imaging low-metal or non-metallic landmines. In this paper we present a complete model of a complex GPR scenario which is solved via finite element method, and includes the actual impulse GPR system, interface, soil and targets. We obtain time domain signatures for different testmines and small objects under different soil conditions which are satisfactorily correlated with measurements. The simulated responses give us a broad understanding about the factors which control the electromagnetic scattering by small objects and are used to interpret the characteristics of the signatures according to the target and background parameters. These obtained waveforms may be applied to reduce the false alarm.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115542385","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637159
K. Rozanov, M. Koledintseva, J. Drewniak
A number of mixing rules are proposed in the literature to predict the dependence of effective material parameters of composites, the permittivity and permeability, on frequency and concentration. Alternatively to the mixing rules, properties of composites can be considered in terms of the Bergman-Milton theory (BMT), which employs the concept of the spectral function. All known mixing rules are particular cases of the BMT. Particularly, the Ghosh-Fuchs theory (GFT) has been proposed based on the BMT. The GFT is shown to agree well with measured material parameters of composites filled with ferromagnetic metal powders. However, the GFT is not convenient for use because of its complicated mathematical form. Herein, a simple analytic formulation of the GFT is proposed. The new mixing rule is based on the shape of the spectral function typical for the Bruggeman effective medium theory with the averaged depolarization factor of inclusions and the percolation thresholds introduced as fitting parameters. Since the permittivity and permeability of a composite are governed by the same mixing rule, these fitting parameters are found from the concentration dependence of permittivity of the composite for further use in the analysis of the frequency dependence of permeability. The proposed mixing law is valid for the case of nearly spherical shape of inclusions in the composite, e. g., stone-like inclusions.
{"title":"A new mixing rule for predicting of frequency-dependent material parameters of composites","authors":"K. Rozanov, M. Koledintseva, J. Drewniak","doi":"10.1109/URSI-EMTS.2010.5637159","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637159","url":null,"abstract":"A number of mixing rules are proposed in the literature to predict the dependence of effective material parameters of composites, the permittivity and permeability, on frequency and concentration. Alternatively to the mixing rules, properties of composites can be considered in terms of the Bergman-Milton theory (BMT), which employs the concept of the spectral function. All known mixing rules are particular cases of the BMT. Particularly, the Ghosh-Fuchs theory (GFT) has been proposed based on the BMT. The GFT is shown to agree well with measured material parameters of composites filled with ferromagnetic metal powders. However, the GFT is not convenient for use because of its complicated mathematical form. Herein, a simple analytic formulation of the GFT is proposed. The new mixing rule is based on the shape of the spectral function typical for the Bruggeman effective medium theory with the averaged depolarization factor of inclusions and the percolation thresholds introduced as fitting parameters. Since the permittivity and permeability of a composite are governed by the same mixing rule, these fitting parameters are found from the concentration dependence of permittivity of the composite for further use in the analysis of the frequency dependence of permeability. The proposed mixing law is valid for the case of nearly spherical shape of inclusions in the composite, e. g., stone-like inclusions.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116569443","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637262
C. Luca, R. Stefanelli, D. Trinchero, P. Besso, G. Dauron
The performances of arrays for high power applications may be heavily affected by the mutual coupling introduced among the radiators. The phenomenon is particularly annoying when high coupling-sensitive radiators are used. The paper focuses on a simple and low computational cost method aimed to compensate the undesired coupling effects which could bring the antenna performance to be different from the theoretical ones. The method is demonstrated via simulation using the commercial software CST MICROWAVE STUDIO®.
{"title":"An efficient method to design planar arrays for high power applications by mutual coupling optimization","authors":"C. Luca, R. Stefanelli, D. Trinchero, P. Besso, G. Dauron","doi":"10.1109/URSI-EMTS.2010.5637262","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637262","url":null,"abstract":"The performances of arrays for high power applications may be heavily affected by the mutual coupling introduced among the radiators. The phenomenon is particularly annoying when high coupling-sensitive radiators are used. The paper focuses on a simple and low computational cost method aimed to compensate the undesired coupling effects which could bring the antenna performance to be different from the theoretical ones. The method is demonstrated via simulation using the commercial software CST MICROWAVE STUDIO®.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122987646","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637110
Z. Peng, Jin-Fa Lee
A non-overlapping and non-conformal domain decomposition method (DDM) is presented for modelling large finite antenna arrays. There are two major ingredients in the proposed DDM: (a) A new second-order transmission condition is introduced, which improves convergence of the iterative process. In contrast to previous high order interface conditions, the new condition uses two second-order transverse derivatives to address the slow convergence issue of both TE and TM evanescent modes. Numerical experiments demonstrate that the convergence of the proposed algorithm is quite insensitive to the size of array. (b) The proposed non-conformal DDM not only permits the use of completely independent discretization for each of the sub-domains, but also allows adjacent sub-domains to be geometrically non-conformal. The benefits of the non-conformal nature of the proposed DDM will be fully enjoyed by a large-scale problem of practical interest, which is a 50 by 50 ultra wide band (UWB) array in the presence of a slot frequency selective surface (FSS). Numerical results verify the effectiveness of the proposed method.
{"title":"A non-overlapping and non-conformal domain decomposition method with second order transmission condition for modelling large finite antenna arrays","authors":"Z. Peng, Jin-Fa Lee","doi":"10.1109/URSI-EMTS.2010.5637110","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637110","url":null,"abstract":"A non-overlapping and non-conformal domain decomposition method (DDM) is presented for modelling large finite antenna arrays. There are two major ingredients in the proposed DDM: (a) A new second-order transmission condition is introduced, which improves convergence of the iterative process. In contrast to previous high order interface conditions, the new condition uses two second-order transverse derivatives to address the slow convergence issue of both TE and TM evanescent modes. Numerical experiments demonstrate that the convergence of the proposed algorithm is quite insensitive to the size of array. (b) The proposed non-conformal DDM not only permits the use of completely independent discretization for each of the sub-domains, but also allows adjacent sub-domains to be geometrically non-conformal. The benefits of the non-conformal nature of the proposed DDM will be fully enjoyed by a large-scale problem of practical interest, which is a 50 by 50 ultra wide band (UWB) array in the presence of a slot frequency selective surface (FSS). Numerical results verify the effectiveness of the proposed method.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"168 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129424114","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637039
M. Tinin
The double weighted Fourier transform (DWFT) is proposed for eliminating intensity fluctuations of waves propagating in random inhomogeneous media. Effects of sizes of receiving and transmitting antenna systems on fluctuation reduction at the given spatial processing of the wave field in modes of both weak and strong intensity fluctuations are under study. Efficiency of the fluctuation reduction by the inverse DWFT at finite sizes of receiving and transmitting antenna systems is shown to be determined by the relation between their sizes and the Fresnel radius.
{"title":"Elimination of wave intensity fluctuations in random inhomogeneous media","authors":"M. Tinin","doi":"10.1109/URSI-EMTS.2010.5637039","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637039","url":null,"abstract":"The double weighted Fourier transform (DWFT) is proposed for eliminating intensity fluctuations of waves propagating in random inhomogeneous media. Effects of sizes of receiving and transmitting antenna systems on fluctuation reduction at the given spatial processing of the wave field in modes of both weak and strong intensity fluctuations are under study. Efficiency of the fluctuation reduction by the inverse DWFT at finite sizes of receiving and transmitting antenna systems is shown to be determined by the relation between their sizes and the Fresnel radius.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116302597","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637027
Maryam Dehghani Estarki, X. Yun, Xu Han, R. Vaughan
The dipole is the fundamental elemental antenna. Moreover, the electric dipole and its monopole equivalent on a groundplane are widely used in practice. Despite the long history of dipole research, its complete impedance behaviour remains elusive. In numerical techniques, such as the method of moments, a gap voltage feed can be expected to give a well-defined radiation conductance but a susceptance which is dissimilar to that of a realized antenna, whereas an impressed current feed can give a well-defined radiation resistance, but dissimilar reactance. The reason is that neither of these feeds accurately model the input region of a practical dipole. Two analytic approaches to the dipole impedance are available - the wave structure method and the induced EMF method. The wave structure method does not lend itself to feed detail, but reveals the impact of dipole thickness and length on the impedance of dipoles which is not available from any other approach. It is reliable for short lengths but it remains restricted to an infinitesimal feed gap, i.e., different to a practical dipole antenna. The induced EMF method is accurate for short and impracticably thin antennas. Electromagnetic simulation techniques can be used for practical dipole thicknesses, but no theory is available to benchmark the results of the numerical experiments. The feed modeling remains a long standing problem in terms of accurately matching the complete impedance to physical experimental results. To make a theoretical start on the problem, the induced EMF method with finite feed gap is solved here and the impedance of the thin dipole is presented. The effect of feed gap size for the finite length wire, e.g. the dipole antenna, has not been studied before. From the induced EMF method, the lossless, thin dipole with finite gap turns out to have an extremely wide bandwidth when terminated with 50 or 75 ohms, a new and interesting result in antenna theory.
{"title":"The effect of gap size on dipole impedance using the induced EMF method","authors":"Maryam Dehghani Estarki, X. Yun, Xu Han, R. Vaughan","doi":"10.1109/URSI-EMTS.2010.5637027","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637027","url":null,"abstract":"The dipole is the fundamental elemental antenna. Moreover, the electric dipole and its monopole equivalent on a groundplane are widely used in practice. Despite the long history of dipole research, its complete impedance behaviour remains elusive. In numerical techniques, such as the method of moments, a gap voltage feed can be expected to give a well-defined radiation conductance but a susceptance which is dissimilar to that of a realized antenna, whereas an impressed current feed can give a well-defined radiation resistance, but dissimilar reactance. The reason is that neither of these feeds accurately model the input region of a practical dipole. Two analytic approaches to the dipole impedance are available - the wave structure method and the induced EMF method. The wave structure method does not lend itself to feed detail, but reveals the impact of dipole thickness and length on the impedance of dipoles which is not available from any other approach. It is reliable for short lengths but it remains restricted to an infinitesimal feed gap, i.e., different to a practical dipole antenna. The induced EMF method is accurate for short and impracticably thin antennas. Electromagnetic simulation techniques can be used for practical dipole thicknesses, but no theory is available to benchmark the results of the numerical experiments. The feed modeling remains a long standing problem in terms of accurately matching the complete impedance to physical experimental results. To make a theoretical start on the problem, the induced EMF method with finite feed gap is solved here and the impedance of the thin dipole is presented. The effect of feed gap size for the finite length wire, e.g. the dipole antenna, has not been studied before. From the induced EMF method, the lossless, thin dipole with finite gap turns out to have an extremely wide bandwidth when terminated with 50 or 75 ohms, a new and interesting result in antenna theory.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"342 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113982820","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637024
T. Kosmanis, T. Zygiridis, N. Kantartzis, Paul T. Aisopoulos
The major issue of electromagnetic immunity of automotive electronics to the radiation of vehicle-to-vehicle systems is the subject of this paper. Inter-vehicle communication systems provide a wide range of new services and applications for vehicular environments, but they are still under development. Although very promising for the future of intelligent transportation systems, they may become hazardous for automotive electronics. A core numerical analysis of the electric field produced by such a system is performed by means of the full wave Finite Difference Time Domain method. The electric field intensity levels in a vehicle due to a vehicle-to-vehicle communication system is estimated for various cases according to the corresponding IEEE standard and compared to the maximum allowed levels for electronic devices.
{"title":"Vehicle-to-vehicle communication system EMI characterization on automotive electronics","authors":"T. Kosmanis, T. Zygiridis, N. Kantartzis, Paul T. Aisopoulos","doi":"10.1109/URSI-EMTS.2010.5637024","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637024","url":null,"abstract":"The major issue of electromagnetic immunity of automotive electronics to the radiation of vehicle-to-vehicle systems is the subject of this paper. Inter-vehicle communication systems provide a wide range of new services and applications for vehicular environments, but they are still under development. Although very promising for the future of intelligent transportation systems, they may become hazardous for automotive electronics. A core numerical analysis of the electric field produced by such a system is performed by means of the full wave Finite Difference Time Domain method. The electric field intensity levels in a vehicle due to a vehicle-to-vehicle communication system is estimated for various cases according to the corresponding IEEE standard and compared to the maximum allowed levels for electronic devices.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127935177","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637071
A. Yarovoy, X. Zhuge
In this paper, application of near-field digital beamforming for shallow subsurface imaging is described. The main novelty of the approach is SIMO topology of the sensing (single transmit - multiple receive antennas). Dedicated antenna systems and imaging algorithms have been developed in order to take maximal advantages from the SIMO data acquisition. Verification of the approach has been done by development of a radar system for landmine detection. Field tests have demonstrated reliable detection of antipersonnel mines by scanning velocity of 10m/s.
{"title":"SIMO-based approach for subsurface sensing","authors":"A. Yarovoy, X. Zhuge","doi":"10.1109/URSI-EMTS.2010.5637071","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637071","url":null,"abstract":"In this paper, application of near-field digital beamforming for shallow subsurface imaging is described. The main novelty of the approach is SIMO topology of the sensing (single transmit - multiple receive antennas). Dedicated antenna systems and imaging algorithms have been developed in order to take maximal advantages from the SIMO data acquisition. Verification of the approach has been done by development of a radar system for landmine detection. Field tests have demonstrated reliable detection of antipersonnel mines by scanning velocity of 10m/s.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131926407","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637127
S. Matos, C. Paiva, A. Barbosa
Moving isotropic media are analyzed considering superluminal phase velocities instead of the usual subluminal regime. The following new effects arise: i) a complex aberration, i.e., angles that are complex in the proper frame can correspond to real angles in the lab frame; ii) Cerenkov effect occurs although the usual condition associated with this effect, in which the relative phase velocity is below the velocity between frames, is not verified. Dispersion and losses are mandatory in order to respect causality, therefore, a Lorentz causal dispersive model is considered. We show that losses play a very important role in the superluminal regime. Without losses the predicted effects could occur for non-relativistic velocities between frames.
{"title":"Complex aberration and a new Cerenkov effect for superluminal phase velocities","authors":"S. Matos, C. Paiva, A. Barbosa","doi":"10.1109/URSI-EMTS.2010.5637127","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637127","url":null,"abstract":"Moving isotropic media are analyzed considering superluminal phase velocities instead of the usual subluminal regime. The following new effects arise: i) a complex aberration, i.e., angles that are complex in the proper frame can correspond to real angles in the lab frame; ii) Cerenkov effect occurs although the usual condition associated with this effect, in which the relative phase velocity is below the velocity between frames, is not verified. Dispersion and losses are mandatory in order to respect causality, therefore, a Lorentz causal dispersive model is considered. We show that losses play a very important role in the superluminal regime. Without losses the predicted effects could occur for non-relativistic velocities between frames.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132323311","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637266
B. Jonsson, M. Gustafsson
An upper bound on the effective area and bandwidth product for linearly polarized array antennas is derived. The bound is based on the forward scattering sum rule that relates the antenna properties with the polarizability of the antenna structure. The results are illustrated for a dipole array and a capacitively loaded dipole array with numerical simulations.
{"title":"Limitations on the effective area and bandwidth product for array antennas","authors":"B. Jonsson, M. Gustafsson","doi":"10.1109/URSI-EMTS.2010.5637266","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637266","url":null,"abstract":"An upper bound on the effective area and bandwidth product for linearly polarized array antennas is derived. The bound is based on the forward scattering sum rule that relates the antenna properties with the polarizability of the antenna structure. The results are illustrated for a dipole array and a capacitively loaded dipole array with numerical simulations.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130219256","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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