Pub Date : 2008-02-01DOI: 10.1177/1042391506074089
Y. Kang, G. Hadjisophocleous, H. Khoo
Spray-on fire protection is widely used in protecting building members, such as beams, against fire. As this protective coating may be damaged during the service life of the beams, it is essential that the effect of this damage on the fire resistance of a steel beam be understood. A numerical study has been conducted to investigate the reduction in the cross-section moment capacity of protected steel beams exposed to the ISO 834 standard fire due to partial loss of spray-on fire protection. Hot-rolled I-shape steel beams according to CAN/CSA—G40.20/ G40.21-98 specifications are used in this study. Results of the study indicate that the reduction of cross-section moment capacity due to the partial loss of protection strongly depends on the area of the protection damage. The reduction of cross-section moment capacity is also affected by several other factors, such as damage shape, damage location, damage penetration, and the weight and depth of the steel section.
{"title":"Effect of Partial loss of Spray-on Protection on the Load Capacity of Steel Beams during a Standard Fire","authors":"Y. Kang, G. Hadjisophocleous, H. Khoo","doi":"10.1177/1042391506074089","DOIUrl":"https://doi.org/10.1177/1042391506074089","url":null,"abstract":"Spray-on fire protection is widely used in protecting building members, such as beams, against fire. As this protective coating may be damaged during the service life of the beams, it is essential that the effect of this damage on the fire resistance of a steel beam be understood. A numerical study has been conducted to investigate the reduction in the cross-section moment capacity of protected steel beams exposed to the ISO 834 standard fire due to partial loss of spray-on fire protection. Hot-rolled I-shape steel beams according to CAN/CSA—G40.20/ G40.21-98 specifications are used in this study. Results of the study indicate that the reduction of cross-section moment capacity due to the partial loss of protection strongly depends on the area of the protection damage. The reduction of cross-section moment capacity is also affected by several other factors, such as damage shape, damage location, damage penetration, and the weight and depth of the steel section.","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"18 1","pages":"5-27"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391506074089","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323562","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 : 2008-02-01DOI: 10.1177/1042391507080813
B. Husted, G. Holmstedt
This article investigates the importance of using draft curtains to obtain faster sprinkler activation with three different models-two computational fluid dynamics (CFD) models (CFX 4.4 and fire dynamics simulator (FDS) 4.07) and a zone model (Argos) containing a ceiling-jet formula - for an actual scenario in an entertainment center in Denmark. It is found that a draft curtain has some effect on sprinkler activation, reducing activation time from 8% to 15%, depending on the model implemented. The positions of the sprinklers with in the vertical computational grid of the CFD simulations have a greater influence on the activation of the sprinkler, where FDS is more sensitive than CFX. It is confirmed that heat transfer from the ceiling jet to the ceiling has little influence on the results. The zone model with a ceiling-jet formula gives 10—20% slower sprinkler activation than the CFD results when the sprinkler is close to the ceiling, but is still considered very useful in view of the faster calculation time.
{"title":"Influence of Draft Curtains on Sprinkler Activation - Comparison of Three Different Models","authors":"B. Husted, G. Holmstedt","doi":"10.1177/1042391507080813","DOIUrl":"https://doi.org/10.1177/1042391507080813","url":null,"abstract":"This article investigates the importance of using draft curtains to obtain faster sprinkler activation with three different models-two computational fluid dynamics (CFD) models (CFX 4.4 and fire dynamics simulator (FDS) 4.07) and a zone model (Argos) containing a ceiling-jet formula - for an actual scenario in an entertainment center in Denmark. It is found that a draft curtain has some effect on sprinkler activation, reducing activation time from 8% to 15%, depending on the model implemented. The positions of the sprinklers with in the vertical computational grid of the CFD simulations have a greater influence on the activation of the sprinkler, where FDS is more sensitive than CFX. It is confirmed that heat transfer from the ceiling jet to the ceiling has little influence on the results. The zone model with a ceiling-jet formula gives 10—20% slower sprinkler activation than the CFD results when the sprinkler is close to the ceiling, but is still considered very useful in view of the faster calculation time.","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"18 1","pages":"29-54"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391507080813","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323879","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 : 2007-11-01DOI: 10.1177/1042391507070547
J. Woycheese
This study investigates how changes to an emergency voice communication system (EVCS) or the building environment affect speech intelligibility in four spaces of an office building: lobby, stairwell, dining area, and open-floor-plan office space. Effects of additional or alternate speaker locations, floor and wall coverings, and background noise on intelligibility are measured via objective means (i.e., meters that evaluated the speech transmission index (STI) of a test signal broadcast via the EVCS). Current practice recommends measurement spacing that appears to appropriately characterize the single-floor spaces, although changes to the environment can reduce STI measurements by nearly 20%. Several suggestions address concerns of when and where to perform speech intelligibility testing.
{"title":"Speech Intelligibility Measurements in an Office Building","authors":"J. Woycheese","doi":"10.1177/1042391507070547","DOIUrl":"https://doi.org/10.1177/1042391507070547","url":null,"abstract":"This study investigates how changes to an emergency voice communication system (EVCS) or the building environment affect speech intelligibility in four spaces of an office building: lobby, stairwell, dining area, and open-floor-plan office space. Effects of additional or alternate speaker locations, floor and wall coverings, and background noise on intelligibility are measured via objective means (i.e., meters that evaluated the speech transmission index (STI) of a test signal broadcast via the EVCS). Current practice recommends measurement spacing that appears to appropriately characterize the single-floor spaces, although changes to the environment can reduce STI measurements by nearly 20%. Several suggestions address concerns of when and where to perform speech intelligibility testing.","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"245-269"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391507070547","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323425","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 : 2007-11-01DOI: 10.1177/1042391507074681
M. Spearpoint
A standardized, object-oriented building product model for buildings is introduced that can be used as a means of electronic exchange between various software tools. The ability to transfer architectural data between a commercially available computer-aided design (CAD) program and a widely available zone fire simulation tool illustrates the applicability of this model in fire engineering. This article describes the software developed to interpret the building product model and the test buildings used to verify the exchange process. In general the building geometry, topology, and other properties can be transferred satisfactorily but some inconsistencies exist due to the structure of the building product model, the CAD implementation of the model, and the simplifications required by the zone modeling approach.
{"title":"Transfer of Architectural Data from the IFC Building Product Model to a Fire Simulation Software Tool","authors":"M. Spearpoint","doi":"10.1177/1042391507074681","DOIUrl":"https://doi.org/10.1177/1042391507074681","url":null,"abstract":"A standardized, object-oriented building product model for buildings is introduced that can be used as a means of electronic exchange between various software tools. The ability to transfer architectural data between a commercially available computer-aided design (CAD) program and a widely available zone fire simulation tool illustrates the applicability of this model in fire engineering. This article describes the software developed to interpret the building product model and the test buildings used to verify the exchange process. In general the building geometry, topology, and other properties can be transferred satisfactorily but some inconsistencies exist due to the structure of the building product model, the CAD implementation of the model, and the simplifications required by the zone modeling approach.","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"271-292"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391507074681","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323530","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 : 2007-11-01DOI: 10.1177/1042391507077198
V. Kodur, Monther B. Dwaikat
A numerical model, in the form of a computer program, is presented for tracing the fire behavior of reinforced concrete (RC) beams over the entire range of loading from pre-fire conditions to collapse under fire. The three stages associated with the analysis of fire resistance; namely, establishing the fire temperature-time development, calculating the heat transfer through the structure from the fire, and the structural analysis are explained. The model, which accounts for nonlinear material properties at elevated temperatures, is capable of predicting the fire resistance of RC beams under realistic fire scenarios, load levels, and failure criteria. The validity of the numerical model is established by comparing the predictions from the computer program with results from full-scale fire resistance tests. Through the results of numerical study, it is shown that the type of failure criterion, load level, and fire scenario have significant influence on fire resistance of RC beams. The computer program can be used to undertake performance-based fire safety design of RC beams for any value of the significant parameters, such as fire exposure, concrete cover thickness, section dimensions, concrete strength, concrete type, and load intensity.
{"title":"Performance-based Fire Safety Design of Reinforced Concrete Beams:","authors":"V. Kodur, Monther B. Dwaikat","doi":"10.1177/1042391507077198","DOIUrl":"https://doi.org/10.1177/1042391507077198","url":null,"abstract":"A numerical model, in the form of a computer program, is presented for tracing the fire behavior of reinforced concrete (RC) beams over the entire range of loading from pre-fire conditions to collapse under fire. The three stages associated with the analysis of fire resistance; namely, establishing the fire temperature-time development, calculating the heat transfer through the structure from the fire, and the structural analysis are explained. The model, which accounts for nonlinear material properties at elevated temperatures, is capable of predicting the fire resistance of RC beams under realistic fire scenarios, load levels, and failure criteria. The validity of the numerical model is established by comparing the predictions from the computer program with results from full-scale fire resistance tests. Through the results of numerical study, it is shown that the type of failure criterion, load level, and fire scenario have significant influence on fire resistance of RC beams. The computer program can be used to undertake performance-based fire safety design of RC beams for any value of the significant parameters, such as fire exposure, concrete cover thickness, section dimensions, concrete strength, concrete type, and load intensity.","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"293-320"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391507077198","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323726","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 : 2007-08-01DOI: 10.1177/1042391507059434
V. Babrauskas
Ignition has been systematically, scientifically studied for about a century now. But the development of knowledge in this area has been uneven, and while an advanced understanding has been reached in some areas, knowledge is scant in others. A review of the literature of the field indicates that the following are some of the notable areas where engineering calculation methods are poor or lacking: hot-surface ignition of liquids; ignition of liquid sprays or aerosols; ignition of solids from hot bodies (hot solids or liquids); ignition of solids by small flames; glowing ignition of solids, especially of lignocellulosic materials; almost all aspects of the ignition of dust clouds; and electrical fires. It is also noted that, despite a century's research, there have been very few theories developed in the ignition field that have engineering utility. The vast majority of theoretical development efforts have produced unwieldy computational models that would require a plethora of generally unavailable input d...
{"title":"Ignition: A Century of Research and an Assessment of Our Current Status","authors":"V. Babrauskas","doi":"10.1177/1042391507059434","DOIUrl":"https://doi.org/10.1177/1042391507059434","url":null,"abstract":"Ignition has been systematically, scientifically studied for about a century now. But the development of knowledge in this area has been uneven, and while an advanced understanding has been reached in some areas, knowledge is scant in others. A review of the literature of the field indicates that the following are some of the notable areas where engineering calculation methods are poor or lacking: hot-surface ignition of liquids; ignition of liquid sprays or aerosols; ignition of solids from hot bodies (hot solids or liquids); ignition of solids by small flames; glowing ignition of solids, especially of lignocellulosic materials; almost all aspects of the ignition of dust clouds; and electrical fires. It is also noted that, despite a century's research, there have been very few theories developed in the ignition field that have engineering utility. The vast majority of theoretical development efforts have produced unwieldy computational models that would require a plethora of generally unavailable input d...","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"165-183"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391507059434","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323578","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 : 2007-08-01DOI: 10.1177/1042391507069336
G. Hadjisophocleous, Z. Fu, S. Fu, C. Dutcher
This article presents a zone model for the prediction of fire growth in a commercial compartment of an office building as part of a fire risk and cost assessment software package. The model developed is a combination of a transient, two-zone submodel used for the pre-flashover fire state and a quasi-steady, single-zone submodel for the post-flashover state. In the two-zone submodel, the selected four independent governing variables are pressure, enthalpy of the upper layer, and the masses of the upper and lower layers. To determine the conditions in the fire compartment, the model considers combustion, fluid flow, and heat transfer. The single-zone submodel includes the energy balance equation, and equations of energy losses due to smoke flow, conduction through the compartment walls, and radiation. The article also presents results of model validation using experimental data from tests in a standard room and in an experimental atrium with a smoke exhaust system. Comparisons of smoke, temperature, interfa...
{"title":"Prediction of Fire Growth for Compartments of Office Buildings as Part of a Fire Risk/Cost Assessment Model","authors":"G. Hadjisophocleous, Z. Fu, S. Fu, C. Dutcher","doi":"10.1177/1042391507069336","DOIUrl":"https://doi.org/10.1177/1042391507069336","url":null,"abstract":"This article presents a zone model for the prediction of fire growth in a commercial compartment of an office building as part of a fire risk and cost assessment software package. The model developed is a combination of a transient, two-zone submodel used for the pre-flashover fire state and a quasi-steady, single-zone submodel for the post-flashover state. In the two-zone submodel, the selected four independent governing variables are pressure, enthalpy of the upper layer, and the masses of the upper and lower layers. To determine the conditions in the fire compartment, the model considers combustion, fluid flow, and heat transfer. The single-zone submodel includes the energy balance equation, and equations of energy losses due to smoke flow, conduction through the compartment walls, and radiation. The article also presents results of model validation using experimental data from tests in a standard room and in an experimental atrium with a smoke exhaust system. Comparisons of smoke, temperature, interfa...","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"185-209"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391507069336","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323652","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 : 2007-08-01DOI: 10.1177/1042391507069634
E. H. Yii, C. Fleischmann, A. Buchanan
The Kawagoe vent flow model has been widely used to study fully developed compartment fires. It is well known that the Kawagoe model is only adequate for compartments with relatively small openings because it overestimates the vent flow rates for compartments with large openings. For a compartment with a very wide opening occupying a large fraction of one wall, experimental observations show that a uniformly distributed fuel load within could produce a line fire parallel to the opening, slowly progressing into the compartment. In this article, analytical analysis has been performed to study the vent flow due to a line plume fire within the compartment, with comparisons to the Kawagoe vent flow model. The analysis shows that for large openings, the vent flow is dictated by the plume entrainment, and as the size of the opening is reduced, the flow across the opening becomes restricted by the opening geometry, approaching the flow rate predicted by the Kawagoe model. Based on the line plume entrainment model...
{"title":"Vent Flows in Fire Compartments with Large Openings","authors":"E. H. Yii, C. Fleischmann, A. Buchanan","doi":"10.1177/1042391507069634","DOIUrl":"https://doi.org/10.1177/1042391507069634","url":null,"abstract":"The Kawagoe vent flow model has been widely used to study fully developed compartment fires. It is well known that the Kawagoe model is only adequate for compartments with relatively small openings because it overestimates the vent flow rates for compartments with large openings. For a compartment with a very wide opening occupying a large fraction of one wall, experimental observations show that a uniformly distributed fuel load within could produce a line fire parallel to the opening, slowly progressing into the compartment. In this article, analytical analysis has been performed to study the vent flow due to a line plume fire within the compartment, with comparisons to the Kawagoe vent flow model. The analysis shows that for large openings, the vent flow is dictated by the plume entrainment, and as the size of the opening is reduced, the flow across the opening becomes restricted by the opening geometry, approaching the flow rate predicted by the Kawagoe model. Based on the line plume entrainment model...","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"211-237"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391507069634","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323749","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 : 2007-05-01DOI: 10.1177/1042391506074091
H. Kung, Martin J. Pabich, Kerry M. Bell, E. D. Jackson, S. Franson
Currently, the NFPA standard for the installation of sprinkler systems (NFPA 13) requires that early suppression fast response (ESFR) sprinklers be specifically listed for use with antifreeze mixtu...
{"title":"ESFR Sprinkler Protection of Class II Commodity in Cold Storage Warehouses using Propylene Glycol Antifreeze Agent","authors":"H. Kung, Martin J. Pabich, Kerry M. Bell, E. D. Jackson, S. Franson","doi":"10.1177/1042391506074091","DOIUrl":"https://doi.org/10.1177/1042391506074091","url":null,"abstract":"Currently, the NFPA standard for the installation of sprinkler systems (NFPA 13) requires that early suppression fast response (ESFR) sprinklers be specifically listed for use with antifreeze mixtu...","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"145-157"},"PeriodicalIF":0.0,"publicationDate":"2007-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391506074091","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323570","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 : 2007-05-01DOI: 10.1177/1042391506064908
I. Thomas, K. Moinuddin, I. Bennetts
Results from an experimental program undertaken to study the effect of fuel quantity and location on ethanol pool fires in the open and in a small enclosure (an ISO 9705 room) are compared with simulations using the Fire Dynamics Simulator version 4.03 (FDS4). The fuel in trays is placed at three locations (front, back, and center) within the room enclosure as well as directly under the calorimeter hood. The measured heat release rate (HRR) is found to vary substantially when a fuel package consisting of different quantities of ethanol is placed at different locations within the room. Instead of prescribing this HRR into the FDS simulation, these experimental results are compared with HRR predictions obtained using the FDS4 combustion model. The comparison reveals that there are significant and variable differences between the experimental results and the FDS4 predictions in contrast to simulations where the HRR is prescribed.
{"title":"The Effect of Fuel Quantity and Location on Small Enclosure Fires","authors":"I. Thomas, K. Moinuddin, I. Bennetts","doi":"10.1177/1042391506064908","DOIUrl":"https://doi.org/10.1177/1042391506064908","url":null,"abstract":"Results from an experimental program undertaken to study the effect of fuel quantity and location on ethanol pool fires in the open and in a small enclosure (an ISO 9705 room) are compared with simulations using the Fire Dynamics Simulator version 4.03 (FDS4). The fuel in trays is placed at three locations (front, back, and center) within the room enclosure as well as directly under the calorimeter hood. The measured heat release rate (HRR) is found to vary substantially when a fuel package consisting of different quantities of ethanol is placed at different locations within the room. Instead of prescribing this HRR into the FDS simulation, these experimental results are compared with HRR predictions obtained using the FDS4 combustion model. The comparison reveals that there are significant and variable differences between the experimental results and the FDS4 predictions in contrast to simulations where the HRR is prescribed.","PeriodicalId":50192,"journal":{"name":"Journal of Fire Protection Engineering","volume":"17 1","pages":"85-102"},"PeriodicalIF":0.0,"publicationDate":"2007-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1042391506064908","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65323273","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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