Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344415
T. Kisielewicz, F. Fiamingo, Z. Flisowski, B. Kuca, G. B. Lo Piparo, C. Mazzetti
The present paper aims to illustrate the influence of the main factors which affect the selection and installation of an SPD for the protection of electrical and electronic systems against overcurrent and overvoltage due to direct lightning flash to a structure. The two most typical SPDs are considered, namely switching and limiting type. Simple rules are established for the selection of effective SPD with regard to the discharge current, its protection level and location.
{"title":"Factors influencing the selection and installation of surge protective devices for low voltage systems","authors":"T. Kisielewicz, F. Fiamingo, Z. Flisowski, B. Kuca, G. B. Lo Piparo, C. Mazzetti","doi":"10.1109/ICLP.2012.6344415","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344415","url":null,"abstract":"The present paper aims to illustrate the influence of the main factors which affect the selection and installation of an SPD for the protection of electrical and electronic systems against overcurrent and overvoltage due to direct lightning flash to a structure. The two most typical SPDs are considered, namely switching and limiting type. Simple rules are established for the selection of effective SPD with regard to the discharge current, its protection level and location.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"3 12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114405997","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344369
M. Troubat, F. Barrière, E. Perrin
This paper proposes a new method to reduce and control the electromagnetic field due to a lightning current flowing down the down-conductors around a structure. The influence of the number of down-conductors and the earthing resistance value on the radiated field is studied thanks to a parametric study.
{"title":"Reduction and mastering of electromagnetic field due to lightning in a structure","authors":"M. Troubat, F. Barrière, E. Perrin","doi":"10.1109/ICLP.2012.6344369","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344369","url":null,"abstract":"This paper proposes a new method to reduce and control the electromagnetic field due to a lightning current flowing down the down-conductors around a structure. The influence of the number of down-conductors and the earthing resistance value on the radiated field is studied thanks to a parametric study.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114987995","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344245
S. Baron, R. Southey, Qizhang Xie, S. Fortin, F. Dawalibi
This article shows how a lighting shielding study of a large plant can be completed based on limited available data, such as 3D screen shots, plan view drawings and elevations of the tallest structures. The shielding study was carried out using a highly efficient 3-D graphics-based lightning interception surface rendering method [4], based on the Electro-geometric Model (EGM) defined in IEC 62305 [1], with a strike radius of 45.0 m, which corresponds to a Class III lightning protection system. Calculations and design of the shielding system were carried out with the SESShield-3D module of the CDEGS software package [2]. A number of zones, some separated by large distances, required lightning shielding designs. The design of one such zone is discussed in this article.
{"title":"Shielding design study for a large plant using a 3-D graphics-based lightning interception surface rendering and intersection method","authors":"S. Baron, R. Southey, Qizhang Xie, S. Fortin, F. Dawalibi","doi":"10.1109/ICLP.2012.6344245","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344245","url":null,"abstract":"This article shows how a lighting shielding study of a large plant can be completed based on limited available data, such as 3D screen shots, plan view drawings and elevations of the tallest structures. The shielding study was carried out using a highly efficient 3-D graphics-based lightning interception surface rendering method [4], based on the Electro-geometric Model (EGM) defined in IEC 62305 [1], with a strike radius of 45.0 m, which corresponds to a Class III lightning protection system. Calculations and design of the shielding system were carried out with the SESShield-3D module of the CDEGS software package [2]. A number of zones, some separated by large distances, required lightning shielding designs. The design of one such zone is discussed in this article.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132120982","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}
Many factors are required to be considered when determining efficient lightning protection methods for power distribution lines, including the causes of lightning surge and the topology and insulation level of the power distribution lines. This study experimentally clarifies the flashover characteristics of 6.6-kV power distribution insulators currently being used by considering polarity differences and polluted conditions. Furthermore, this study proposes an approximate formula that is based on the sparkover model to calculate the flashover characteristics of 6.6-kV power distribution insulators, and contributes to the improvement in insulation coordination throughout power distribution systems.
{"title":"Approximate formula for surface V-t characteristics of 6.6-kV distribution insulator","authors":"Satoshi Matsumoto, Tomoyuki Sato, Hideki Honda, Shigeru Yokoyama","doi":"10.1109/ICLP.2012.6344282","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344282","url":null,"abstract":"Many factors are required to be considered when determining efficient lightning protection methods for power distribution lines, including the causes of lightning surge and the topology and insulation level of the power distribution lines. This study experimentally clarifies the flashover characteristics of 6.6-kV power distribution insulators currently being used by considering polarity differences and polluted conditions. Furthermore, this study proposes an approximate formula that is based on the sparkover model to calculate the flashover characteristics of 6.6-kV power distribution insulators, and contributes to the improvement in insulation coordination throughout power distribution systems.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132208729","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344263
G. Lugrin, N. Mora, F. Rachidi, M. Rubinstein, G. Diendorfer
In this paper, we discuss the use of the Electromagnetic Time Reversal (EMTR) method to locate lightning discharges. The main problem of EMTR is that losses are not invariant under time reversal. In this paper, we propose 3 different models of back-propagation to fix this problem. Simulations are made to evaluate the accuracy of the proposed methods. It is shown that by assuming a lossless back-propagation model, the resulting location errors are in the order of some hundreds of meters. It is also shown that a theoretically exact estimate can be obtained considering a back-propagation over a fictitious `inverted-loss' ground.
{"title":"On the use of the Time Reversal of Electromagnetic fields to locate lightning discharges","authors":"G. Lugrin, N. Mora, F. Rachidi, M. Rubinstein, G. Diendorfer","doi":"10.1109/ICLP.2012.6344263","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344263","url":null,"abstract":"In this paper, we discuss the use of the Electromagnetic Time Reversal (EMTR) method to locate lightning discharges. The main problem of EMTR is that losses are not invariant under time reversal. In this paper, we propose 3 different models of back-propagation to fix this problem. Simulations are made to evaluate the accuracy of the proposed methods. It is shown that by assuming a lossless back-propagation model, the resulting location errors are in the order of some hundreds of meters. It is also shown that a theoretically exact estimate can be obtained considering a back-propagation over a fictitious `inverted-loss' ground.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134048977","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344376
D. Ariza, F. Roman, O. Escobar, O. Montero
In this work two important differences between the expected behavior of the corona current as a function of the electric field when measured in the laboratory and under natural thunderstorm conditions are reported. The first difference is related to a non-linear increase of the corona current when the natural electric field increases. The second is a delay observed between the corona current and the electric field. To explain this behavior a hypothesis is proposed: The wind removes the space charge produced by the corona electrode increasing the corona current. The removed space charge is detected by the electric field sensor decreasing the measured electric field. Both corona current and the natural electric field were recorded in Bogota Colombia, in the time period July to November, 2011. From the recorded data, 22 thunderstorms were selected to be reported. Additionally, the influence of the corona space charge on an electric field mill was studied under laboratory conditions.
{"title":"Corona current and space charge during a thunderstorm","authors":"D. Ariza, F. Roman, O. Escobar, O. Montero","doi":"10.1109/ICLP.2012.6344376","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344376","url":null,"abstract":"In this work two important differences between the expected behavior of the corona current as a function of the electric field when measured in the laboratory and under natural thunderstorm conditions are reported. The first difference is related to a non-linear increase of the corona current when the natural electric field increases. The second is a delay observed between the corona current and the electric field. To explain this behavior a hypothesis is proposed: The wind removes the space charge produced by the corona electrode increasing the corona current. The removed space charge is detected by the electric field sensor decreasing the measured electric field. Both corona current and the natural electric field were recorded in Bogota Colombia, in the time period July to November, 2011. From the recorded data, 22 thunderstorms were selected to be reported. Additionally, the influence of the corona space charge on an electric field mill was studied under laboratory conditions.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133571861","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344221
N. Muot, C. Girard, E. bachelier, X. F. Onera, E. bachelier
In this paper, we present a strategy based on a multi-domain hybrid approach in the time domain by coupling 3D methods (FDTD, FVTD ...) with a transmission line (TL) method to simulate large-scale electromagnetic problems. The paper gives the main keys to couple together the numerical methods based on different formulations. The challenge is first to have an implicit definition of the electromagnetic field in the theory of transmission lines, and secondly to take into account the effects of the soil on the induced currents and on the electromagnetic field. The aim of this work is to propose an efficient numerical strategy to compute the electromagnetic induced effects of lightning on large and complex sites, composed of several interconnected distant buildings.
{"title":"Lightning effects on interconnected ground installations: Hybrid 3D-1D numerical approach in time domain","authors":"N. Muot, C. Girard, E. bachelier, X. F. Onera, E. bachelier","doi":"10.1109/ICLP.2012.6344221","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344221","url":null,"abstract":"In this paper, we present a strategy based on a multi-domain hybrid approach in the time domain by coupling 3D methods (FDTD, FVTD ...) with a transmission line (TL) method to simulate large-scale electromagnetic problems. The paper gives the main keys to couple together the numerical methods based on different formulations. The challenge is first to have an implicit definition of the electromagnetic field in the theory of transmission lines, and secondly to take into account the effects of the soil on the induced currents and on the electromagnetic field. The aim of this work is to propose an efficient numerical strategy to compute the electromagnetic induced effects of lightning on large and complex sites, composed of several interconnected distant buildings.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116199501","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344289
Mary Ann Cooper, Ronald L. Holle
Although several individuals in the United States (US) were working on lightning safety efforts, it was not until the early 1990's that researchers from many fields of study began to work together as they became aware of others with similar interests. The first organized effort on a national scale was in 1998 when a multidisciplinary group of recognized lightning researchers and experts met at an American Meteorological Society meeting and agreed on the Lightning Safety Guidelines (LSG) which were published in a number of venues. Beginning in 2001, a Lightning Safety Awareness (LSA) campaign was initiated by the US National Oceanic and Atmospheric Administration (NOAA) with many of the LSG individuals as well as others [1.2]. This campaign, now called Lightning Safety Week (LSW), occurs the last full week of June annually. The LSW website (www.lightningsafety.noaa.gov) has become the premier lightning safety site with general information, games, puzzles, public service announcements as well as special sections for the media, teachers, boaters, and many other interests and concerns. LSW members and others have continued to be active in promoting lightning inj ury prevention, train others, and develop lightning safety themes such as 'When Thunder Roars, Go Indoors!' that can be learned by any age. An interactive game using a cartoon character 'Leon, the Lightning Safety Lion' was developed to help teach lightning safety to children but is well liked by adults as well. The materials from this website are all free for download, use and modification by anyone who is interested in injury prevention and lightning safety. Collectively, the LSW team and others have made themselves available for thousands of interviews with newspapers, radio and television, worked on dozens of documentaries, as well as continuing their own research and publication. There has been a steady decrease in the lightning fatality rate over the past twenty years of work with a rate of less than O.lImillion US population in each of the last three years, in part due to the educational efforts of this group and the media's support in disseminating lightning safety information.
{"title":"Lightning safety campaigns - USA experience","authors":"Mary Ann Cooper, Ronald L. Holle","doi":"10.1109/ICLP.2012.6344289","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344289","url":null,"abstract":"Although several individuals in the United States (US) were working on lightning safety efforts, it was not until the early 1990's that researchers from many fields of study began to work together as they became aware of others with similar interests. The first organized effort on a national scale was in 1998 when a multidisciplinary group of recognized lightning researchers and experts met at an American Meteorological Society meeting and agreed on the Lightning Safety Guidelines (LSG) which were published in a number of venues. Beginning in 2001, a Lightning Safety Awareness (LSA) campaign was initiated by the US National Oceanic and Atmospheric Administration (NOAA) with many of the LSG individuals as well as others [1.2]. This campaign, now called Lightning Safety Week (LSW), occurs the last full week of June annually. The LSW website (www.lightningsafety.noaa.gov) has become the premier lightning safety site with general information, games, puzzles, public service announcements as well as special sections for the media, teachers, boaters, and many other interests and concerns. LSW members and others have continued to be active in promoting lightning inj ury prevention, train others, and develop lightning safety themes such as 'When Thunder Roars, Go Indoors!' that can be learned by any age. An interactive game using a cartoon character 'Leon, the Lightning Safety Lion' was developed to help teach lightning safety to children but is well liked by adults as well. The materials from this website are all free for download, use and modification by anyone who is interested in injury prevention and lightning safety. Collectively, the LSW team and others have made themselves available for thousands of interviews with newspapers, radio and television, worked on dozens of documentaries, as well as continuing their own research and publication. There has been a steady decrease in the lightning fatality rate over the past twenty years of work with a rate of less than O.lImillion US population in each of the last three years, in part due to the educational efforts of this group and the media's support in disseminating lightning safety information.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125854429","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344356
V. P. Androvitsaneas, I. Gonos, I. Stathopulos
Grounding resistance could be reduced significantly with the usage of ground enhancing compounds in lightning protection systems. This paper presents the results of a series of field measurements on commercially-available ground enhancing compounds. It is the aim of this study to assess the behavior of ground enhancing compounds, which are widely used in grounding systems, in order to decrease the grounding resistance value. It is well known that most of the rise of potential of the grounding rod is determined by the soil resistivity surrounding the grounding rod and the magnitude of the applied current. As a result, the lowest feasible grounding resistance value is desirable, in order to provide the lowest impede path for fault currents to be dispersed into the earth, in the shortest time possible. For this purpose, five grounding rods were driven, each one of them, in different ground enhancing compounds. The measurement results are presented in relation to time and to rainfall. Furthermore, several thoughts, comments and proposals are presented about: a) the use feasibility of ground enhancing compounds, b) the choice of the suitable compound, in relation with the cost and the achieved grounding resistance value, c) the time and weather conditions influence on ground enhancing compound behavior.
{"title":"Performance of ground enhancing compounds during the year","authors":"V. P. Androvitsaneas, I. Gonos, I. Stathopulos","doi":"10.1109/ICLP.2012.6344356","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344356","url":null,"abstract":"Grounding resistance could be reduced significantly with the usage of ground enhancing compounds in lightning protection systems. This paper presents the results of a series of field measurements on commercially-available ground enhancing compounds. It is the aim of this study to assess the behavior of ground enhancing compounds, which are widely used in grounding systems, in order to decrease the grounding resistance value. It is well known that most of the rise of potential of the grounding rod is determined by the soil resistivity surrounding the grounding rod and the magnitude of the applied current. As a result, the lowest feasible grounding resistance value is desirable, in order to provide the lowest impede path for fault currents to be dispersed into the earth, in the shortest time possible. For this purpose, five grounding rods were driven, each one of them, in different ground enhancing compounds. The measurement results are presented in relation to time and to rainfall. Furthermore, several thoughts, comments and proposals are presented about: a) the use feasibility of ground enhancing compounds, b) the choice of the suitable compound, in relation with the cost and the achieved grounding resistance value, c) the time and weather conditions influence on ground enhancing compound behavior.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123781719","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 : 2012-11-12DOI: 10.1109/ICLP.2012.6344350
M. Edirisinghe, A. Liyanage, V. Cooray
The core objective of this study was to investigate the behavior of electric discharge exited in air over water and to study the way in which the lightning impulse is conducted into a water body. During the experiments, standard lightning impulses from -550 kV to 350 kV have been directed on water surfaces and surface discharges has been photographed using two cameras. The conductivity of the water has been varied from 41.5 μS/cm to 51.5 mS/cm. Analysis carried out in the study revealed that the current rather travels along the water surface than into the water when the conductivity of the water is low. A logarithmic variation was observed between the calculated electric field and the conductivity. For this variation a saturating trend could be observed and it appeared as if there is a critical value for the electric field below which no penetration will occur at any level of conductivity. Based on the experimental results of this study it can be estimated that to be less than 1.5×105 V/m for the positive breakdown and -5.0×105 V/m for the negative breakdown.
{"title":"Critical electric field needed for the propagation of surface discharges on water","authors":"M. Edirisinghe, A. Liyanage, V. Cooray","doi":"10.1109/ICLP.2012.6344350","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344350","url":null,"abstract":"The core objective of this study was to investigate the behavior of electric discharge exited in air over water and to study the way in which the lightning impulse is conducted into a water body. During the experiments, standard lightning impulses from -550 kV to 350 kV have been directed on water surfaces and surface discharges has been photographed using two cameras. The conductivity of the water has been varied from 41.5 μS/cm to 51.5 mS/cm. Analysis carried out in the study revealed that the current rather travels along the water surface than into the water when the conductivity of the water is low. A logarithmic variation was observed between the calculated electric field and the conductivity. For this variation a saturating trend could be observed and it appeared as if there is a critical value for the electric field below which no penetration will occur at any level of conductivity. Based on the experimental results of this study it can be estimated that to be less than 1.5×105 V/m for the positive breakdown and -5.0×105 V/m for the negative breakdown.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125005507","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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