Pub Date : 2015-11-30DOI: 10.1109/SIPDA.2015.7339273
Feng Minxue, J. Xue, Z. Yingying, Yu Zhou
With the three-dimensional lightning data, the relationship between lightning and radar, field mill data of thunderstorm on September 28th, 2014 is analyzed. The results show that, the lightning moves from north to south, mainly concentrated in the Jiangpu District, Jiangning District, Liuhe District and the center of Nanjing where lightning current is the strongest with the average of 31.06kA. During the development period of thunderstorm, cloud flash is relatively more active than cloud-ground flash, the occurrence of cloud flash indicates that the thunderstorm is coming and strengthening. Less lightning happen when echo scatters and low intensity, with the development of echo, lightning become intense, the combined reflective factor changes consistently with lightning. The change trend of lightning density is basically consistent with echo top height, the higher the echo top is, the more lightning happens. Lightning intensity changes slightly behind the echo top height. Before the first cloud flash, electric field changes quickly, with the sharp change of electric field, the thunderstorm becomes mature, lightning frequency increases rapidly until the storm dissipated, the electric field changes slowly, then lightning reduce. Three-dimensional lightning combined with other observation data, can be better used in the study of thunderstorm which has an important practical significance on the lightning monitoring and early warning.
{"title":"Analysis of three-dimensional lightning data in a thunderstorm event","authors":"Feng Minxue, J. Xue, Z. Yingying, Yu Zhou","doi":"10.1109/SIPDA.2015.7339273","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339273","url":null,"abstract":"With the three-dimensional lightning data, the relationship between lightning and radar, field mill data of thunderstorm on September 28th, 2014 is analyzed. The results show that, the lightning moves from north to south, mainly concentrated in the Jiangpu District, Jiangning District, Liuhe District and the center of Nanjing where lightning current is the strongest with the average of 31.06kA. During the development period of thunderstorm, cloud flash is relatively more active than cloud-ground flash, the occurrence of cloud flash indicates that the thunderstorm is coming and strengthening. Less lightning happen when echo scatters and low intensity, with the development of echo, lightning become intense, the combined reflective factor changes consistently with lightning. The change trend of lightning density is basically consistent with echo top height, the higher the echo top is, the more lightning happens. Lightning intensity changes slightly behind the echo top height. Before the first cloud flash, electric field changes quickly, with the sharp change of electric field, the thunderstorm becomes mature, lightning frequency increases rapidly until the storm dissipated, the electric field changes slowly, then lightning reduce. Three-dimensional lightning combined with other observation data, can be better used in the study of thunderstorm which has an important practical significance on the lightning monitoring and early warning.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127081303","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339306
Paulo Fernandes Costa, Timoteo Louis Costa
IEC STd 62793, “Protection Against Lightning - Thunderstorm Warning Systems” [1] will be released, according IEC information, in September 2015. It is expected that in the beginning of the XIII SIPDA (end of September 2015) this new standard will already be valid. This is a release of utmost importance, since this standard will cover, among others aspects, the protection of people against lightning in open areas, a topic never covered by international standards before. This article reviews the most important aspects of this standard and discusses the impact of its release in the world, having a special focus in Brazil.
{"title":"Protection of people against lightning in open environments: Impact of publication of IEC Std 62793: “Protection Against Lightning - Thunderstorm Warning Systems”","authors":"Paulo Fernandes Costa, Timoteo Louis Costa","doi":"10.1109/SIPDA.2015.7339306","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339306","url":null,"abstract":"IEC STd 62793, “Protection Against Lightning - Thunderstorm Warning Systems” [1] will be released, according IEC information, in September 2015. It is expected that in the beginning of the XIII SIPDA (end of September 2015) this new standard will already be valid. This is a release of utmost importance, since this standard will cover, among others aspects, the protection of people against lightning in open areas, a topic never covered by international standards before. This article reviews the most important aspects of this standard and discusses the impact of its release in the world, having a special focus in Brazil.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131457069","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339303
F. H. Silveira, S. Visacro, R. E. de Souza Filho
This work presents a discussion on the traditional methodologies presented by CIGRE and IEEE to calculate the lightning outage rate of high voltage transmission lines in terms of backflashover occurrence. The main aspects of such methodologies are reviewed. The simplifications and approximations adopted to determine the outage rate are discussed. Systematic simulations are developed considering a typical 138-kV line configuration. The obtained results in terms of peak overvoltage, critical current and backflashover rate are compared with those obtained by an advanced methodology composed by an accurate electromagnetic model (HEM) to calculate the overvoltage across insulator strings and an elaborate model (Disruptive effect - DE) to evaluate the flashover occurrence across insulators. Very distinct backflashover outage rates were presented. In general, CIGRE and IEEE methodologies yield large and lower outage rate, respectively, in comparison to those estimated by the advanced methodology. The results indicate the need of incorporating the recent advances of the area in the calculation of outage rate, aiming the improvement of the quality of the results given by traditional methodologies.
{"title":"Calculation of backflashover outage rate of transmission lines: A discussion on traditional methodologies and recent advances","authors":"F. H. Silveira, S. Visacro, R. E. de Souza Filho","doi":"10.1109/SIPDA.2015.7339303","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339303","url":null,"abstract":"This work presents a discussion on the traditional methodologies presented by CIGRE and IEEE to calculate the lightning outage rate of high voltage transmission lines in terms of backflashover occurrence. The main aspects of such methodologies are reviewed. The simplifications and approximations adopted to determine the outage rate are discussed. Systematic simulations are developed considering a typical 138-kV line configuration. The obtained results in terms of peak overvoltage, critical current and backflashover rate are compared with those obtained by an advanced methodology composed by an accurate electromagnetic model (HEM) to calculate the overvoltage across insulator strings and an elaborate model (Disruptive effect - DE) to evaluate the flashover occurrence across insulators. Very distinct backflashover outage rates were presented. In general, CIGRE and IEEE methodologies yield large and lower outage rate, respectively, in comparison to those estimated by the advanced methodology. The results indicate the need of incorporating the recent advances of the area in the calculation of outage rate, aiming the improvement of the quality of the results given by traditional methodologies.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133371556","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339323
A. Rousseau, Fernanda Cruz, Xuyun Zang, Lu Dongbo
There are various kinds of surges in LV system superposing the AC operating voltage. This document presents the test on MOV type SPDs to discover the possible reasons for fire under operation that are observed in field. The tests are including the AC test, surge test, surge on AC voltage and multiple surges. The test results lead to the solutions on how to deal with the safety problem.
{"title":"Degradation analysis of MOV type SPDs with surge supurposing AC operating voltage","authors":"A. Rousseau, Fernanda Cruz, Xuyun Zang, Lu Dongbo","doi":"10.1109/SIPDA.2015.7339323","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339323","url":null,"abstract":"There are various kinds of surges in LV system superposing the AC operating voltage. This document presents the test on MOV type SPDs to discover the possible reasons for fire under operation that are observed in field. The tests are including the AC test, surge test, surge on AC voltage and multiple surges. The test results lead to the solutions on how to deal with the safety problem.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"343 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116446803","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339276
J. Paulino, Pedro Campos Assuncao, C. Barbosa
This paper analyses the lightning induced voltages in large loops, considering the propagation of the scattered voltages along the loop. The loop is modeled as a transmission line having two possible configurations: two wires above ground and one wire above ground. The inducing electric field components are introduced gradually, in order to identify the effect of each one of them. It is shown that the electric field components due to the scalar potential also produce scattered voltages in the loop. The results show that the propagation of the scattered voltages produces large oscillations on the induced voltage, and that their amplitude and wavelength increases with increasing loop length. It is also shown that the electric field developed in lossy ground has no effect on the induced voltages if the loop is above ground, but it has a predominant effect if the loop is on the ground surface.
{"title":"Lightning induced voltages in large loops","authors":"J. Paulino, Pedro Campos Assuncao, C. Barbosa","doi":"10.1109/SIPDA.2015.7339276","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339276","url":null,"abstract":"This paper analyses the lightning induced voltages in large loops, considering the propagation of the scattered voltages along the loop. The loop is modeled as a transmission line having two possible configurations: two wires above ground and one wire above ground. The inducing electric field components are introduced gradually, in order to identify the effect of each one of them. It is shown that the electric field components due to the scalar potential also produce scattered voltages in the loop. The results show that the propagation of the scattered voltages produces large oscillations on the induced voltage, and that their amplitude and wavelength increases with increasing loop length. It is also shown that the electric field developed in lossy ground has no effect on the induced voltages if the loop is above ground, but it has a predominant effect if the loop is on the ground surface.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124202997","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339309
Maryory Aixa Rojas Camargo, F. J. Campos
In this paper the electrical and magnetic field interference in inhabited rights-of-way produced by a 115 kV double circuit transmission line is analyzed The software used in this investigation was COMSOL Multiphysics®. Results were validated with electric and magnetic field site measurements.
{"title":"Electromagnetic interferences analysis in inhabited rights of way","authors":"Maryory Aixa Rojas Camargo, F. J. Campos","doi":"10.1109/SIPDA.2015.7339309","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339309","url":null,"abstract":"In this paper the electrical and magnetic field interference in inhabited rights-of-way produced by a 115 kV double circuit transmission line is analyzed The software used in this investigation was COMSOL Multiphysics®. Results were validated with electric and magnetic field site measurements.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"35 7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132615752","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339322
A. Paiva, M. Saba, K. Naccarato, C. Schumann, R. Jaques, M. A. Ferro
This work aimed to investigate which pulses (M-components and/or subsequent return stroke) of the upward lightning are detected by BrasilDAT lightning location network. It was found that, these pulses are similar to downward lightning pulses and therefore, they were well detected by the network. This report is based on a set of 29 upward lightning and 16 downward lightning whose strike points are known. All lightning used were recorded in the Jaraguá Peak region. High-speed cameras and electric field sensors were used in this analysis to find out the rise time of the waveform and the peak value of the electric field. The comparison with the pulses of the downward lightning recorded by cameras allowed us to validate the BrasilDAT network, determining the detection efficiency and location error. We found a detection efficiency of 37-56%, and a location error of approximately 600 meters. It was observed that the M components of the upward lightning resemble the subsequent return strokes of the downward lightning because the luminosity prior to the pulse is low and the rise time of the electric field waveform is short. The current peaks of the pulses of the upward and downward lightning were intense. These facts explain why BrasilDAT captured these pulses, since the networks tend to discard pulses with low intensity and long rise times.
{"title":"Detection of M-components and return strokes in upward and downward lightning flashes","authors":"A. Paiva, M. Saba, K. Naccarato, C. Schumann, R. Jaques, M. A. Ferro","doi":"10.1109/SIPDA.2015.7339322","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339322","url":null,"abstract":"This work aimed to investigate which pulses (M-components and/or subsequent return stroke) of the upward lightning are detected by BrasilDAT lightning location network. It was found that, these pulses are similar to downward lightning pulses and therefore, they were well detected by the network. This report is based on a set of 29 upward lightning and 16 downward lightning whose strike points are known. All lightning used were recorded in the Jaraguá Peak region. High-speed cameras and electric field sensors were used in this analysis to find out the rise time of the waveform and the peak value of the electric field. The comparison with the pulses of the downward lightning recorded by cameras allowed us to validate the BrasilDAT network, determining the detection efficiency and location error. We found a detection efficiency of 37-56%, and a location error of approximately 600 meters. It was observed that the M components of the upward lightning resemble the subsequent return strokes of the downward lightning because the luminosity prior to the pulse is low and the rise time of the electric field waveform is short. The current peaks of the pulses of the upward and downward lightning were intense. These facts explain why BrasilDAT captured these pulses, since the networks tend to discard pulses with low intensity and long rise times.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126569077","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339331
V. L. Coelho, Lucas Fritzen Venturini, H. Almaguer, R. A. Coelho, A. Piantini, W. Boaventura, J. Paulino, Plínio Luiz Nosaki
This paper aims at contributing to the study of grounding systems behavior due to direct lightning currents striking rural distribution lines located in high flash density areas. The high current density, from direct flashes, causes soil ionization phenomenon in grounding systems. In order to investigate the ionization phenomenon under various grounding conditions, impulse tests were performed on three types of soils with different resistivities, considering different humidity conditions. Using the Energy Balance method, values for the critical electric field and thermal soil constant were determined. The obtained values for the critical electric field are very close to those found in the literature and the soil thermal constant showed a strong correlation with the critical electric field.
{"title":"Soil resistivity behavior under high current density values using the Energy Balance method","authors":"V. L. Coelho, Lucas Fritzen Venturini, H. Almaguer, R. A. Coelho, A. Piantini, W. Boaventura, J. Paulino, Plínio Luiz Nosaki","doi":"10.1109/SIPDA.2015.7339331","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339331","url":null,"abstract":"This paper aims at contributing to the study of grounding systems behavior due to direct lightning currents striking rural distribution lines located in high flash density areas. The high current density, from direct flashes, causes soil ionization phenomenon in grounding systems. In order to investigate the ionization phenomenon under various grounding conditions, impulse tests were performed on three types of soils with different resistivities, considering different humidity conditions. Using the Energy Balance method, values for the critical electric field and thermal soil constant were determined. The obtained values for the critical electric field are very close to those found in the literature and the soil thermal constant showed a strong correlation with the critical electric field.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114734081","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339287
Guilherme S. Lima, Rafael M. Gomes, Ronaldo E. S. Filho, A. De Conti, F. H. Silveira, S. Visacro, W. A. Souza
This paper investigates the influence of XLPE-covered cables on the impulse withstand voltage of a typical structure used in single-phase compact distribution lines in Brazil. For comparison purposes, two different procedures are adopted for estimating the impulse withstand voltage of this structure under standard positive lightning impulses. One considers a bare cable and the other assumes a XPLE-covered cable. For the impulse withstand analysis considering the bare cable, the up-and-down method is used for determining the critical flashover overvoltage (CFO) of the structure. The corresponding Vxt curve is also determined using the standard procedures. For the impulse withstand analysis considering the XPLE-covered cable, the breakdown voltage was determined in two different laboratory tests, the first one considering a brand new cable and the second one considering a punctured cable. Both tests were performed for two different cable manufacturers.
{"title":"Influence of XLPE-covered cables on the impulse withstand voltage of a single-phase structure used in compact distribution lines","authors":"Guilherme S. Lima, Rafael M. Gomes, Ronaldo E. S. Filho, A. De Conti, F. H. Silveira, S. Visacro, W. A. Souza","doi":"10.1109/SIPDA.2015.7339287","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339287","url":null,"abstract":"This paper investigates the influence of XLPE-covered cables on the impulse withstand voltage of a typical structure used in single-phase compact distribution lines in Brazil. For comparison purposes, two different procedures are adopted for estimating the impulse withstand voltage of this structure under standard positive lightning impulses. One considers a bare cable and the other assumes a XPLE-covered cable. For the impulse withstand analysis considering the bare cable, the up-and-down method is used for determining the critical flashover overvoltage (CFO) of the structure. The corresponding Vxt curve is also determined using the standard procedures. For the impulse withstand analysis considering the XPLE-covered cable, the breakdown voltage was determined in two different laboratory tests, the first one considering a brand new cable and the second one considering a punctured cable. Both tests were performed for two different cable manufacturers.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"300 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122162950","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 : 2015-11-30DOI: 10.1109/SIPDA.2015.7339290
A. Rousseau, Nicolas Autipout, Nicolas Peyrus, Patrick Eustachon
In 2011, the Fukushima nuclear plant accident in Japan was a major accident for the nuclear industry in the world. Following this event it became necessary to investigate if nuclear safety facilities were able to withstand natural stresses more severe than usual: earthquake, tidal wave, flood ... Obviously lightning is one of those natural stresses. Lightning impulses different from standardized lightning impulses must then be considered taking into account CIGRE distributions and experience feedback.
{"title":"Protection of safety installations for nuclear sites","authors":"A. Rousseau, Nicolas Autipout, Nicolas Peyrus, Patrick Eustachon","doi":"10.1109/SIPDA.2015.7339290","DOIUrl":"https://doi.org/10.1109/SIPDA.2015.7339290","url":null,"abstract":"In 2011, the Fukushima nuclear plant accident in Japan was a major accident for the nuclear industry in the world. Following this event it became necessary to investigate if nuclear safety facilities were able to withstand natural stresses more severe than usual: earthquake, tidal wave, flood ... Obviously lightning is one of those natural stresses. Lightning impulses different from standardized lightning impulses must then be considered taking into account CIGRE distributions and experience feedback.","PeriodicalId":296478,"journal":{"name":"2015 International Symposium on Lightning Protection (XIII SIPDA)","volume":"07 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122704233","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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