Pub Date : 2018-06-01DOI: 10.1109/ICGPR.2018.8441635
Félix Antonio Centeno Salas, D. C. Freyre
For the development of this work an unconventional technique to estimate the spatial distribution of petrophysical parameters was applied. The inversion of the amplitude is applied to the GPR data for estimating reflectivity, the used algorithm requires preconditioning of the data by conventional processing techniques. The proposed inversion algorithm, operating with band matrices, had shown to be computationally more efficient than the conventional methods of inversion. The spatial distribution of physical properties is estimated by a recursive calculation technique, with the constraint of having information of the near surface lithological sequence. Petrophysical parameters are estimated by applying an empirical relationship between electrical and physical properties of the subsoil granular materials, similar to those studied during the development of this work. The methodology for the analysis of GPR records proposed in this paper was used for the characterization of a study site, with available lithological information from a geotechnical borehole. GPR profiles obtained by the inversion proposed method show that the simulated stratigraphy corresponds to the lithological sequence at the study site.
{"title":"Estimation of Petrophysical Parameters of Granular Materials, Applying an Amplitud Inversion From GPR Data: Case Study Irapuato, GTO., Mexico","authors":"Félix Antonio Centeno Salas, D. C. Freyre","doi":"10.1109/ICGPR.2018.8441635","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441635","url":null,"abstract":"For the development of this work an unconventional technique to estimate the spatial distribution of petrophysical parameters was applied. The inversion of the amplitude is applied to the GPR data for estimating reflectivity, the used algorithm requires preconditioning of the data by conventional processing techniques. The proposed inversion algorithm, operating with band matrices, had shown to be computationally more efficient than the conventional methods of inversion. The spatial distribution of physical properties is estimated by a recursive calculation technique, with the constraint of having information of the near surface lithological sequence. Petrophysical parameters are estimated by applying an empirical relationship between electrical and physical properties of the subsoil granular materials, similar to those studied during the development of this work. The methodology for the analysis of GPR records proposed in this paper was used for the characterization of a study site, with available lithological information from a geotechnical borehole. GPR profiles obtained by the inversion proposed method show that the simulated stratigraphy corresponds to the lithological sequence at the study site.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"333 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123549895","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441633
D. Pasculli, A. Natali, W. Salvatore, F. Morelli, D. Morandi
Ground penetrating radar is a non-invasive technique that, amongst the various available state-of-the-art methods, is capable of accurately locating both metallic and nonmetallic buried objects. The main object of this paper is to describe the application of a GPR strategy to the non-destructive testing of concrete structures, particularly bridges, where there is a need to identify, quantify and categorize structural reinforcements. The new C-Thrue radar, developed by IDS GeoRadar, was used to investigate two bridges near Pisa (Italy). The acquisition of dense and regular grids was used to provide a full reconstruction of the geometry of the investigated area. Moreover, through the use of sensors in different polarizations, and dedicated data processing techniques, the C-Thrue radar enables the creation of spatially correlated data sets that represent scanned 3-D volumes of the ground, allowing demonstrable benefits in overall assessment of the required structural parameters.
{"title":"Investigation of reinforced concrete bridges by using a dual-polarized high-frequency GPR","authors":"D. Pasculli, A. Natali, W. Salvatore, F. Morelli, D. Morandi","doi":"10.1109/ICGPR.2018.8441633","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441633","url":null,"abstract":"Ground penetrating radar is a non-invasive technique that, amongst the various available state-of-the-art methods, is capable of accurately locating both metallic and nonmetallic buried objects. The main object of this paper is to describe the application of a GPR strategy to the non-destructive testing of concrete structures, particularly bridges, where there is a need to identify, quantify and categorize structural reinforcements. The new C-Thrue radar, developed by IDS GeoRadar, was used to investigate two bridges near Pisa (Italy). The acquisition of dense and regular grids was used to provide a full reconstruction of the geometry of the investigated area. Moreover, through the use of sensors in different polarizations, and dedicated data processing techniques, the C-Thrue radar enables the creation of spatially correlated data sets that represent scanned 3-D volumes of the ground, allowing demonstrable benefits in overall assessment of the required structural parameters.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130398991","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441605
W. van Verre, F. Podd, Yee M. Tan, Xianyang Gao, A. Peyton
This paper presents a comparison between solid and resisitively loaded bowtie antennas in GPR applications for the purpose of finding buried landmines. The resistively-loaded antennas were first evaluated over dry sand in a laboratory-based experiment with a landmine surrogate. Further testing, comparing the performance of the loaded antennas to that of solid bowtie antennas, was performed over real soil, with a real landmine. Using the loaded bowtie antennas, the system got a response from the target in the indoor experiment but not in the outdoor experiment. The system did detect the buried landmine in the outdoor experiment when using the solid bowtie antennas. It is likely that the losses in the real soil were too high compared to the losses in dry sand for the system to be able to get a response using loaded antennas. The GPR system tested in this paper forms part of a dual-modality system for humanitarian demining applications.
{"title":"A Comparison of Solid and Loaded Bowtie Antennas in GPR for the Detection of Buried Landmines","authors":"W. van Verre, F. Podd, Yee M. Tan, Xianyang Gao, A. Peyton","doi":"10.1109/ICGPR.2018.8441605","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441605","url":null,"abstract":"This paper presents a comparison between solid and resisitively loaded bowtie antennas in GPR applications for the purpose of finding buried landmines. The resistively-loaded antennas were first evaluated over dry sand in a laboratory-based experiment with a landmine surrogate. Further testing, comparing the performance of the loaded antennas to that of solid bowtie antennas, was performed over real soil, with a real landmine. Using the loaded bowtie antennas, the system got a response from the target in the indoor experiment but not in the outdoor experiment. The system did detect the buried landmine in the outdoor experiment when using the solid bowtie antennas. It is likely that the losses in the real soil were too high compared to the losses in dry sand for the system to be able to get a response using loaded antennas. The GPR system tested in this paper forms part of a dual-modality system for humanitarian demining applications.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128402965","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441637
A. Rodionov, P. Ryazantsev
This paper presents data collected through ground penetrating radar (GPR) surveys of shallow waterbodies in the Republic of Karelia (Russian Federation). In addition to the analysis of radar profiles, we briefly describe the electrophysical parameters of the waterbodies surveyed. The effect of water mineralization and electrical conductivity on the dynamic characteristics of the GPR signal is also investigated.
{"title":"GPR study of sapropel deposits in Karelian shallow water areas","authors":"A. Rodionov, P. Ryazantsev","doi":"10.1109/ICGPR.2018.8441637","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441637","url":null,"abstract":"This paper presents data collected through ground penetrating radar (GPR) surveys of shallow waterbodies in the Republic of Karelia (Russian Federation). In addition to the analysis of radar profiles, we briefly describe the electrophysical parameters of the waterbodies surveyed. The effect of water mineralization and electrical conductivity on the dynamic characteristics of the GPR signal is also investigated.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130923931","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441644
I. Prokopovich, D. Edemsky, A. Popov, P. Morozov
The results of GPR survey of fortification objects on Matua island, Kuril archipelago are discussed. Selected results of discovering the storage places of military equipment and infrastructure of the period of the Second World War are presented. It is shown that the use of an extended-power GPR with 50–350 MHz antennas provides an efficient solution of the subsurface location problem in highly stratified wet grounds of volcanic origin.
{"title":"GPR Survey of Fortification Objects on Matua Island","authors":"I. Prokopovich, D. Edemsky, A. Popov, P. Morozov","doi":"10.1109/ICGPR.2018.8441644","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441644","url":null,"abstract":"The results of GPR survey of fortification objects on Matua island, Kuril archipelago are discussed. Selected results of discovering the storage places of military equipment and infrastructure of the period of the Second World War are presented. It is shown that the use of an extended-power GPR with 50–350 MHz antennas provides an efficient solution of the subsurface location problem in highly stratified wet grounds of volcanic origin.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134420678","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441608
S. Ebihara, Shyuhei Kotani, Kengo Fujiwara
In this study we investigated the influence of a borehole on the estimation of wave arrival direction using a dipole array antenna in a directional borehole radar system. According to computer simulation, if a plane wave is incident at certain elevation angles, there is little arrival time difference among the dipole array signals. In this case, the estimation of arrival direction fails. When the elevation angle of wave incidence is very steep, the estimated direction of arrival becomes opposite to the true direction (i.e., off by 180 deg.). We conducted a cross-hole measurement to verify these phenomena. We observed little arrival time difference among the dipole array signals at a certain elevation angle we deemed the critical angle. For a wave incident on the dipole array at very steep angles, field experiments found that the estimated direction of arrival was almost opposite to the true direction like the computer simulation.
{"title":"Plane Wave Arrival Time Studies with a Dipole Array Antenna in a Borehole","authors":"S. Ebihara, Shyuhei Kotani, Kengo Fujiwara","doi":"10.1109/ICGPR.2018.8441608","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441608","url":null,"abstract":"In this study we investigated the influence of a borehole on the estimation of wave arrival direction using a dipole array antenna in a directional borehole radar system. According to computer simulation, if a plane wave is incident at certain elevation angles, there is little arrival time difference among the dipole array signals. In this case, the estimation of arrival direction fails. When the elevation angle of wave incidence is very steep, the estimated direction of arrival becomes opposite to the true direction (i.e., off by 180 deg.). We conducted a cross-hole measurement to verify these phenomena. We observed little arrival time difference among the dipole array signals at a certain elevation angle we deemed the critical angle. For a wave incident on the dipole array at very steep angles, field experiments found that the estimated direction of arrival was almost opposite to the true direction like the computer simulation.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"184 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133717155","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441684
F. Xie, J. Sham, W. Lai, Xavier Dérobert
Accurate wave velocity estimation is an important part to determine the quality and reliability of GPR survey results, such as positioning of underground utility and characterization of materials. An algorithm was proposed to estimate the velocity accurately by modeling the GPR signal travel path. Both the effects of factors of antenna separation and radius of cylindrical target were taken into account. This model helped to establish a nonlinear relationship among the parameters of horizontal displacement of antenna, GPR signal travel time, wave propagation velocity. Levenberg-Marquardt iteration method was used to solve the non-linear least square fitting. Validation experiments were conducted in lab environment. The reflection data of an Y25 steel bar in air at depth 0.2m, 0.3m, 0.4m and 0.5m were extracted to test the algorithm. Errors of the estimated velocities is around 2% to 3% which is quite small and acceptable in reality. It is believed that this algorithm is qualified for future accurate GPR positioning survey and condition survey.
{"title":"A modified algorithm for accurate GPR wave velocity estimation with common offset setting antenna","authors":"F. Xie, J. Sham, W. Lai, Xavier Dérobert","doi":"10.1109/ICGPR.2018.8441684","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441684","url":null,"abstract":"Accurate wave velocity estimation is an important part to determine the quality and reliability of GPR survey results, such as positioning of underground utility and characterization of materials. An algorithm was proposed to estimate the velocity accurately by modeling the GPR signal travel path. Both the effects of factors of antenna separation and radius of cylindrical target were taken into account. This model helped to establish a nonlinear relationship among the parameters of horizontal displacement of antenna, GPR signal travel time, wave propagation velocity. Levenberg-Marquardt iteration method was used to solve the non-linear least square fitting. Validation experiments were conducted in lab environment. The reflection data of an Y25 steel bar in air at depth 0.2m, 0.3m, 0.4m and 0.5m were extracted to test the algorithm. Errors of the estimated velocities is around 2% to 3% which is quite small and acceptable in reality. It is believed that this algorithm is qualified for future accurate GPR positioning survey and condition survey.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132090945","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441667
J. van der Kruk, T. Liu, A. Mozaffari, N. Gueting, A. Klotzsche, H. Vereecken, C. Warren, A. Giannopoulos
Ray-based, or approximate, forward modeling techniques have often been used to reduce computational demands for inversion purposes. Due to increasing computational power and possible parallelization of inversion algorithms, accurate forward modeling can be included in advanced inversion approaches such that the full-waveform can be exploited. Here, recent developments of full-waveform ground penetrating radar (GPR) inversions are discussed that yield higher resolution of quantitative medium properties compared to conventional approaches, because of the use of accurate modeling tools that are based on Maxwell's equations. For a limited number of parameters, a combined global and local search using the shuffled complex evolution (SCE) can be used for inversion. For a large number of unknowns, gradient-based optimization methods are commonly used that need a good starting model to prevent them from being trapped in local minima. An overview of the methodological developments for surface and crosshole GPR full-waveform inversion will be given and several applications will be presented. Finally, recent developments and future opportunities will be discussed.
{"title":"GPR full-waveform inversion, recent developments, and future opportunities","authors":"J. van der Kruk, T. Liu, A. Mozaffari, N. Gueting, A. Klotzsche, H. Vereecken, C. Warren, A. Giannopoulos","doi":"10.1109/ICGPR.2018.8441667","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441667","url":null,"abstract":"Ray-based, or approximate, forward modeling techniques have often been used to reduce computational demands for inversion purposes. Due to increasing computational power and possible parallelization of inversion algorithms, accurate forward modeling can be included in advanced inversion approaches such that the full-waveform can be exploited. Here, recent developments of full-waveform ground penetrating radar (GPR) inversions are discussed that yield higher resolution of quantitative medium properties compared to conventional approaches, because of the use of accurate modeling tools that are based on Maxwell's equations. For a limited number of parameters, a combined global and local search using the shuffled complex evolution (SCE) can be used for inversion. For a large number of unknowns, gradient-based optimization methods are commonly used that need a good starting model to prevent them from being trapped in local minima. An overview of the methodological developments for surface and crosshole GPR full-waveform inversion will be given and several applications will be presented. Finally, recent developments and future opportunities will be discussed.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114118678","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441599
Zhenxing Li, Chunlin Huang
In the paper, an experiment is introduced to carry out imaging detection when there is a metallic foreign body in organism, which is a kind of microwave medical penetrating imaging technique commonly used in medicine, breast cancer and stroke. The main contents of the paper are as follows: firstly, several methods of biomedical imaging are briefly introduced. The advantages of microwave medical imaging are illustrated by comparison. Then, the electromagnetic characteristics of the biological tissue are described, in which the two important parameters are relative permittivity and conductivity. The following is a description of the experiment. The biological tissues used in the experiment are simulated biological tissues made of oil, gelatin, sodium chloride and other materials. The advantage of using simulated biological tissue is to reduce the uncertainties, to facilitate control of the relative permittivity and conductivity, and ensure the success of subsequent biologic imaging. Finally, the biomedical imaging results are analyzed, which shows that microwave imaging of metallic foreign bodies in the organism is feasible.
{"title":"Imaging of Metallic Foreign Body in Organism by Microwave","authors":"Zhenxing Li, Chunlin Huang","doi":"10.1109/ICGPR.2018.8441599","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441599","url":null,"abstract":"In the paper, an experiment is introduced to carry out imaging detection when there is a metallic foreign body in organism, which is a kind of microwave medical penetrating imaging technique commonly used in medicine, breast cancer and stroke. The main contents of the paper are as follows: firstly, several methods of biomedical imaging are briefly introduced. The advantages of microwave medical imaging are illustrated by comparison. Then, the electromagnetic characteristics of the biological tissue are described, in which the two important parameters are relative permittivity and conductivity. The following is a description of the experiment. The biological tissues used in the experiment are simulated biological tissues made of oil, gelatin, sodium chloride and other materials. The advantage of using simulated biological tissue is to reduce the uncertainties, to facilitate control of the relative permittivity and conductivity, and ensure the success of subsequent biologic imaging. Finally, the biomedical imaging results are analyzed, which shows that microwave imaging of metallic foreign bodies in the organism is feasible.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"349 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133104856","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 : 2018-06-01DOI: 10.1109/ICGPR.2018.8441591
S. Šesnić, D. Poljak
The paper deals with the characterization of electric field radiated by a GPR antenna and transmitted into a lossy medium. Realistic bow-tie GPR antenna is modeled as an equivalent dipole antenna with current distribution governed by Hallen integral equation. Electric field transmitted into a lossy medium is determined using Boundary Element formalism for the solution of field integral formulas. Electric field distribution at a certain depth is calculated using this procedure.
{"title":"Calculation of the Transient Electric Field Transmitted in a Lossy Medium Radiated by an Equivalent GPR Dipole Antenna","authors":"S. Šesnić, D. Poljak","doi":"10.1109/ICGPR.2018.8441591","DOIUrl":"https://doi.org/10.1109/ICGPR.2018.8441591","url":null,"abstract":"The paper deals with the characterization of electric field radiated by a GPR antenna and transmitted into a lossy medium. Realistic bow-tie GPR antenna is modeled as an equivalent dipole antenna with current distribution governed by Hallen integral equation. Electric field transmitted into a lossy medium is determined using Boundary Element formalism for the solution of field integral formulas. Electric field distribution at a certain depth is calculated using this procedure.","PeriodicalId":269482,"journal":{"name":"2018 17th International Conference on Ground Penetrating Radar (GPR)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121886145","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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