Pub Date : 2016-09-01DOI: 10.1109/ICLP.2016.7791498
Ruihan Qi, Binghao Li, Y. Du
This paper presents a study of lightning induced surges in railway signaling systems with the FDTD method. During an indirect lightning strike, induced surges are observed in the outdoor circuits due to electric and magnetic coupling. The induced surge currents propagate along the signal cables towards the receiving equipment in railway stations. It is found that geometry of the outdoor lines, earthing and bonding practices affect induced surge currents and voltages in the circuits. Equipotential bonding can substantially reduce the induced surge voltage impinging on the equipment in railway stations.
{"title":"Induced surges in railway signaling systems during an indirect lightning strike","authors":"Ruihan Qi, Binghao Li, Y. Du","doi":"10.1109/ICLP.2016.7791498","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791498","url":null,"abstract":"This paper presents a study of lightning induced surges in railway signaling systems with the FDTD method. During an indirect lightning strike, induced surges are observed in the outdoor circuits due to electric and magnetic coupling. The induced surge currents propagate along the signal cables towards the receiving equipment in railway stations. It is found that geometry of the outdoor lines, earthing and bonding practices affect induced surge currents and voltages in the circuits. Equipotential bonding can substantially reduce the induced surge voltage impinging on the equipment in railway stations.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133916386","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}
By global warming, air pollution of environmental issues, and the seriousness of the energy problem, fuel cell vehicles that do not generate CO2 on the time of traveling is being sold. Thereby, hydrogen stations are beginning to be built in various places. Now, because there is no lightning protection guidelines in the hydrogen station, we examined the lightning protection of the human body and equipment in the hydrogen station. We conducted an experiment of applying the impulse voltage to the hydrogen station. The results of the experiment, erroneous operation and failure of the equipment occurred. In addition, the potential difference is generated between the equipment and the earth. Experimental results revealed the damage to the equipment due to nearby lightning strikes. In the case of direct strikes, there is a possibility that the high voltage is applied to the operator.
{"title":"Study of lightning protection for hydrogen station","authors":"Kazuki Oobayashi, Yuta Naito, Nobuyuki Morii, Takeo Ijichi, Nobuhiro Ohno, Shozo Sekioka","doi":"10.1109/ICLP.2016.7791348","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791348","url":null,"abstract":"By global warming, air pollution of environmental issues, and the seriousness of the energy problem, fuel cell vehicles that do not generate CO2 on the time of traveling is being sold. Thereby, hydrogen stations are beginning to be built in various places. Now, because there is no lightning protection guidelines in the hydrogen station, we examined the lightning protection of the human body and equipment in the hydrogen station. We conducted an experiment of applying the impulse voltage to the hydrogen station. The results of the experiment, erroneous operation and failure of the equipment occurred. In addition, the potential difference is generated between the equipment and the earth. Experimental results revealed the damage to the equipment due to nearby lightning strikes. In the case of direct strikes, there is a possibility that the high voltage is applied to the operator.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122168237","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 : 2016-09-01DOI: 10.1109/ICLP.2016.7791445
Z. G. Datsios, P. Mikropoulos
Soil ionization, that is, electrical discharges developing in ground, occurs due to the high electric field associated mainly with lightning currents. Despite having attracted a great interest among researchers from the beginning of the 20th century, soil ionization is far from being completely understood owing to the complex nature and structure of soil. This study investigates breakdown of several dry natural silica sand samples in a quasi-uniform electric field electrode arrangement under standard lightning impulse voltages. The dependence of sand breakdown gradient and time delay on the grain size is assessed. Corona inception, thus also breakdown, is favored by the sand grains as compared with the case of air alone.
{"title":"Impulse breakdown characteristics of dry sand: Effect of sand grain size","authors":"Z. G. Datsios, P. Mikropoulos","doi":"10.1109/ICLP.2016.7791445","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791445","url":null,"abstract":"Soil ionization, that is, electrical discharges developing in ground, occurs due to the high electric field associated mainly with lightning currents. Despite having attracted a great interest among researchers from the beginning of the 20th century, soil ionization is far from being completely understood owing to the complex nature and structure of soil. This study investigates breakdown of several dry natural silica sand samples in a quasi-uniform electric field electrode arrangement under standard lightning impulse voltages. The dependence of sand breakdown gradient and time delay on the grain size is assessed. Corona inception, thus also breakdown, is favored by the sand grains as compared with the case of air alone.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116975961","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 : 2016-09-01DOI: 10.1109/ICLP.2016.7791360
M. Rubinstein, Jacques Zuber, A. Smorgonskiy, F. Rachidi, G. Diendorfer
Upward lightning flashes from towers are sometimes preceded by other lightning activity in the vicinity of the tower. This observation has led to a classification of upward tower lightning into self-initiated, which are not preceded by nearby lightning activity, and other-triggered, for which one or more CG or IC flashes occur within a given preceding interval and within a given distance from the tower. The causality relation between other-triggered flashes and the preceding activity has not been established. In this paper, we hypothesize that at least some of the activity prior to other-triggered tower flashes can be explained as being due to chance rather than causality.
{"title":"Correlation vs. causality in other-triggered upward lightning in tower flashes","authors":"M. Rubinstein, Jacques Zuber, A. Smorgonskiy, F. Rachidi, G. Diendorfer","doi":"10.1109/ICLP.2016.7791360","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791360","url":null,"abstract":"Upward lightning flashes from towers are sometimes preceded by other lightning activity in the vicinity of the tower. This observation has led to a classification of upward tower lightning into self-initiated, which are not preceded by nearby lightning activity, and other-triggered, for which one or more CG or IC flashes occur within a given preceding interval and within a given distance from the tower. The causality relation between other-triggered flashes and the preceding activity has not been established. In this paper, we hypothesize that at least some of the activity prior to other-triggered tower flashes can be explained as being due to chance rather than causality.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123914226","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 : 2016-09-01DOI: 10.1109/ICLP.2016.7791375
A. De Conti, R. Alípio
This paper investigates the influence of considering frequency-dependent ground parameters in the calculation of lightning transients on a two-phase distribution line including the presence of branches. The analysis is focused on propagation effects along the line. It is shown that the influence of frequency-dependent ground parameters is only remarkable if a poorly-conducting ground is considered. It is also shown that the presence of line branches is likely to reduce the relative importance of considering the frequency variation of the ground parameters in the calculation of lightning transients.
{"title":"Lightning transients on branched distribution lines considering frequency-dependent ground parameters","authors":"A. De Conti, R. Alípio","doi":"10.1109/ICLP.2016.7791375","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791375","url":null,"abstract":"This paper investigates the influence of considering frequency-dependent ground parameters in the calculation of lightning transients on a two-phase distribution line including the presence of branches. The analysis is focused on propagation effects along the line. It is shown that the influence of frequency-dependent ground parameters is only remarkable if a poorly-conducting ground is considered. It is also shown that the presence of line branches is likely to reduce the relative importance of considering the frequency variation of the ground parameters in the calculation of lightning transients.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123577511","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}
At present, PVC and balsa wood are usually adopted in the sandwich structure of the wind turbine blade. However, comparative research on the damage characteristics of the two materials under lightning arc is seldom reported. Large current experiment was conducted on PVC and balsa wood, which indicated that under the surge current, there was a more severe reduction in the residual strength of PVC than balsa wood. By the means of molecular reaction dynamics, the chemical reaction process, gas generation characteristics and water motion of the materials were studied quantitatively. As is shown in the visual results, cellulose (main component of balsa wood) was gradually splitting with the degree of polymerization(DP) reducing as time increasing, while there is no obvious change on the DP in the PVC aspect. The degradation of cellulose generated relatively more kinds of small-molecule gases while PVC mainly produced HCl and small amounts of olefins, but the number of gas products from PVC pyrolysis was far much more than that of cellulose. In addition, with many -OH. H and O included in cellulose, there are more H2O molecules absorbed on the cellulose by H bond, which results in a large amount of water content in balsa wood, while, the density of H bond between PVC and water was much lower. Water around the surface of cellulose would turn into vapor that would expand when heated, making it a key factor to the damage of cellulose.
{"title":"Damage mechanism of PVC and balsa wood used in wind turbine blade under thermal effect of lightning strikes","authors":"Jiangyan Yan, Qingmin Li, Guo Zixin, Zhang Li, Weijia Zhao","doi":"10.1109/ICLP.2016.7791477","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791477","url":null,"abstract":"At present, PVC and balsa wood are usually adopted in the sandwich structure of the wind turbine blade. However, comparative research on the damage characteristics of the two materials under lightning arc is seldom reported. Large current experiment was conducted on PVC and balsa wood, which indicated that under the surge current, there was a more severe reduction in the residual strength of PVC than balsa wood. By the means of molecular reaction dynamics, the chemical reaction process, gas generation characteristics and water motion of the materials were studied quantitatively. As is shown in the visual results, cellulose (main component of balsa wood) was gradually splitting with the degree of polymerization(DP) reducing as time increasing, while there is no obvious change on the DP in the PVC aspect. The degradation of cellulose generated relatively more kinds of small-molecule gases while PVC mainly produced HCl and small amounts of olefins, but the number of gas products from PVC pyrolysis was far much more than that of cellulose. In addition, with many -OH. H and O included in cellulose, there are more H2O molecules absorbed on the cellulose by H bond, which results in a large amount of water content in balsa wood, while, the density of H bond between PVC and water was much lower. Water around the surface of cellulose would turn into vapor that would expand when heated, making it a key factor to the damage of cellulose.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128147734","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 : 2016-09-01DOI: 10.1109/ICLP.2016.7791434
A. Kostinskiy, E. Mareev, N. Bogatov, V. Syssoev, Mikhail Andreev, D. Sukharevsky, M. Bulatov, V. Rakov
We have observed unusual plasma formations (UPFs) in artificial clouds of charged water droplets using a high-speed infrared camera operating in conjunction with a high-speed visible-range camera. Inferred plasma parameters were close to those of long-spark leaders observed in the same experiments, while the channel morphology was distinctly different from that of leaders, so that UPFs can be viewed as a new type of in-cloud discharge. These formations can occur in the absence of spark leaders and appear to be manifestations of collective processes building, essentially from scratch, a complex hierarchical network of interacting channels at different stages of development (some of which are hot and live for milliseconds). We believe that the phenomenon should commonly occur in thunderclouds and might give insights on the missing link in the still poorly understood lightning initiation process.
{"title":"A new class of electric discharges in clouds of negatively charged water droplets","authors":"A. Kostinskiy, E. Mareev, N. Bogatov, V. Syssoev, Mikhail Andreev, D. Sukharevsky, M. Bulatov, V. Rakov","doi":"10.1109/ICLP.2016.7791434","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791434","url":null,"abstract":"We have observed unusual plasma formations (UPFs) in artificial clouds of charged water droplets using a high-speed infrared camera operating in conjunction with a high-speed visible-range camera. Inferred plasma parameters were close to those of long-spark leaders observed in the same experiments, while the channel morphology was distinctly different from that of leaders, so that UPFs can be viewed as a new type of in-cloud discharge. These formations can occur in the absence of spark leaders and appear to be manifestations of collective processes building, essentially from scratch, a complex hierarchical network of interacting channels at different stages of development (some of which are hot and live for milliseconds). We believe that the phenomenon should commonly occur in thunderclouds and might give insights on the missing link in the still poorly understood lightning initiation process.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129267536","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 : 2016-09-01DOI: 10.1109/ICLP.2016.7791431
L. Arevalo, V. Cooray
Based on the well-known rolling sphere method, international standards recommend the location of the external lightning protection system of structures. The design of the external lightning protection system of structures of height of less than 60 m can be done by installing a mesh on top of a roof of the structure or by creating a mesh with wires at certain distance from the roof of the structure. The prospective downward leader current that the mesh can incept depends on the size of the mesh and the current magnitude is given as recommendation in the international standards. This paper analyses the relation prospective negative downward leader current vs. mesh size from a lightning attachment model. The model is applied to a perfectly grounded structure with maximum height of 50 m protected by two different external lightning protection systems recommended by the international standards. The results showed difference on magnitude of the prospective downward leader current the standards recommend and the ones obtained using the lightning attachment model for meshes of shorter size. Discrepancies concerning the minimum downward leader current that can be incepted by a mesh made by wires located at certain distance from the ground structure and a mesh located on top of the building are obtained.
{"title":"The mesh method in lightning protection analyzed from a lightning attachment model","authors":"L. Arevalo, V. Cooray","doi":"10.1109/ICLP.2016.7791431","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791431","url":null,"abstract":"Based on the well-known rolling sphere method, international standards recommend the location of the external lightning protection system of structures. The design of the external lightning protection system of structures of height of less than 60 m can be done by installing a mesh on top of a roof of the structure or by creating a mesh with wires at certain distance from the roof of the structure. The prospective downward leader current that the mesh can incept depends on the size of the mesh and the current magnitude is given as recommendation in the international standards. This paper analyses the relation prospective negative downward leader current vs. mesh size from a lightning attachment model. The model is applied to a perfectly grounded structure with maximum height of 50 m protected by two different external lightning protection systems recommended by the international standards. The results showed difference on magnitude of the prospective downward leader current the standards recommend and the ones obtained using the lightning attachment model for meshes of shorter size. Discrepancies concerning the minimum downward leader current that can be incepted by a mesh made by wires located at certain distance from the ground structure and a mesh located on top of the building are obtained.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130908216","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 : 2016-09-01DOI: 10.1109/ICLP.2016.7791443
Volodymyr Shostak, Mikhailo Sypchenko, Thomas Smatloch
Electrodynamic (ED) forces influencing upon lightning protection (LP) components in some typical LP system configurations and conditions are studied. These include: various angles between conductors, their finite lengths, round and flat bar cross-section, grid of conductors, various heights of conductor holders, placement of conductors above metallic cladding and reinforced concrete, various materials, etc. Some practical formulas and examples (grid; conductor going from roof to wall and other) are included, and the scale of stresses affecting the components is discussed. For various current magnitudes and waveforms according to [1], ED forces are estimated by analytical formulas and numerical simulation. In typical LP components, stresses may reach a few units, tens and up to ~180 kN/m, for maximal currents corresponding to LPL 1. For some fastening elements (screws, expansion anchors), the critical levels of current magnitudes (tens of kiloamperes), which able to pull out holders from typical base materials (wood, concrete/brick), are determined. Results are discussed and recommendations provided.
{"title":"Electrodynamic forces affecting lightning protection system components and structures","authors":"Volodymyr Shostak, Mikhailo Sypchenko, Thomas Smatloch","doi":"10.1109/ICLP.2016.7791443","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791443","url":null,"abstract":"Electrodynamic (ED) forces influencing upon lightning protection (LP) components in some typical LP system configurations and conditions are studied. These include: various angles between conductors, their finite lengths, round and flat bar cross-section, grid of conductors, various heights of conductor holders, placement of conductors above metallic cladding and reinforced concrete, various materials, etc. Some practical formulas and examples (grid; conductor going from roof to wall and other) are included, and the scale of stresses affecting the components is discussed. For various current magnitudes and waveforms according to [1], ED forces are estimated by analytical formulas and numerical simulation. In typical LP components, stresses may reach a few units, tens and up to ~180 kN/m, for maximal currents corresponding to LPL 1. For some fastening elements (screws, expansion anchors), the critical levels of current magnitudes (tens of kiloamperes), which able to pull out holders from typical base materials (wood, concrete/brick), are determined. Results are discussed and recommendations provided.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130581102","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 : 2016-09-01DOI: 10.1109/ICLP.2016.7791463
Jian Li, Yao Yao, Xueming Zhou, Danhui Hu, Ling Ruan
Lightning flashover risk evaluation is the basis for choosing proper measures to improve the lightning performance of the transmission lines. Thus, the effectiveness of the measures adopted is directly determined by the evaluation accuracy. At present, the risks are mainly evaluated through comparing the calculated lightning flashover rate (LFOR) of every tower. However, there are so many assumptions and simplifications in the process of calculation. This way will often cause some discrepancies between the evaluated results and operating experience. A new evaluation method based on data mining will be proposed to study the characteristics of the lightning failure history. The association relationship between the lightning failure and altitude, height difference, relative height difference, ground flash density, etc. will be considered to build classification rules library to determine the tower lightning flashover risk. Comparison of the proposed evaluation method with the traditional methods shows that the results deduced through the proposed method is more agree with the operating experience.
{"title":"A new method to evaluate the lightning flashover risk of transmission line based on data mining","authors":"Jian Li, Yao Yao, Xueming Zhou, Danhui Hu, Ling Ruan","doi":"10.1109/ICLP.2016.7791463","DOIUrl":"https://doi.org/10.1109/ICLP.2016.7791463","url":null,"abstract":"Lightning flashover risk evaluation is the basis for choosing proper measures to improve the lightning performance of the transmission lines. Thus, the effectiveness of the measures adopted is directly determined by the evaluation accuracy. At present, the risks are mainly evaluated through comparing the calculated lightning flashover rate (LFOR) of every tower. However, there are so many assumptions and simplifications in the process of calculation. This way will often cause some discrepancies between the evaluated results and operating experience. A new evaluation method based on data mining will be proposed to study the characteristics of the lightning failure history. The association relationship between the lightning failure and altitude, height difference, relative height difference, ground flash density, etc. will be considered to build classification rules library to determine the tower lightning flashover risk. Comparison of the proposed evaluation method with the traditional methods shows that the results deduced through the proposed method is more agree with the operating experience.","PeriodicalId":373744,"journal":{"name":"2016 33rd International Conference on Lightning Protection (ICLP)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129642062","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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