When compared to other accident modes, rollovers have a higher risk of injuries and fatalities and this risk increases dramatically for unbelted occupants. In this chapter, from a comprehensive text on occupant and vehicle responses in rollovers, the authors report on a comparative study between belted rollover occupants who did and did not receive head injuries from roof contact. The authors used the National Accident Sampling System (NASS) database to investigate whether headroom reduction increases the risk of head injury. The authors determine headroom for 155 belted occupants involved in rollover crashes. Results showed that headroom was reduced more in those crashes where the occupant had head injuries than in cases where there were no head injuries; thus, the risk of head injury increases with reduced headroom. The authors conclude that to improve rollover crashworthiness of vehicles, headroom reduction and the belt system should be evaluated simultaneously to upgrade occupant protection.
{"title":"DETERMINATION OF THE SIGNIFICANCE OF ROOF CRUSH ON HEAD AND NECK INJURY TO PASSENGER VEHICLE OCCUPANTS IN ROLLOVER CRASHES. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"G. Rains, J. Kanianthra","doi":"10.4271/950655","DOIUrl":"https://doi.org/10.4271/950655","url":null,"abstract":"When compared to other accident modes, rollovers have a higher risk of injuries and fatalities and this risk increases dramatically for unbelted occupants. In this chapter, from a comprehensive text on occupant and vehicle responses in rollovers, the authors report on a comparative study between belted rollover occupants who did and did not receive head injuries from roof contact. The authors used the National Accident Sampling System (NASS) database to investigate whether headroom reduction increases the risk of head injury. The authors determine headroom for 155 belted occupants involved in rollover crashes. Results showed that headroom was reduced more in those crashes where the occupant had head injuries than in cases where there were no head injuries; thus, the risk of head injury increases with reduced headroom. The authors conclude that to improve rollover crashworthiness of vehicles, headroom reduction and the belt system should be evaluated simultaneously to upgrade occupant protection.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127211121","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}
This paper traces the evolution of the occupant protection requirements in Federal Motor Vehicle Safety Standard (FMVSS) 208 from its beginning as a requirement for seatbelts to be installed in passenger cars to its current requirements that each passenger car provide an air bag and a manual lap/shoulder belt for the driver and right front passenger position beginning in the 1998 model year and that light trucks and vans provide similar protective equipment for the driver and passenger beginning in the 1999 model year. Also discussed and summarized are the various court cases that have challenged different aspects of the automatic crash protection requirements.
{"title":"REGULATORY HISTORY OF AUTOMATIC CRASH PROTECTION IN FMVSS 208. IN: SEAT BELTS: THE DEVELOPMENT OF AN ESSENTIAL SAFETY FEATURE","authors":"Stephen R. Kratzke","doi":"10.4271/950865","DOIUrl":"https://doi.org/10.4271/950865","url":null,"abstract":"This paper traces the evolution of the occupant protection requirements in Federal Motor Vehicle Safety Standard (FMVSS) 208 from its beginning as a requirement for seatbelts to be installed in passenger cars to its current requirements that each passenger car provide an air bag and a manual lap/shoulder belt for the driver and right front passenger position beginning in the 1998 model year and that light trucks and vans provide similar protective equipment for the driver and passenger beginning in the 1999 model year. Also discussed and summarized are the various court cases that have challenged different aspects of the automatic crash protection requirements.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115643278","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}
In this chapter, from a comprehensive text about occupant and vehicle responses in rollovers, the authors report the results of analyses of single-vehicle-accident, tripped-rollover maneuvers involving either light vehicles from four classes of ground vehicles. All vehicles, except for the passenger cars, were evaluated in both unladen and laden states. The authors note that the vehicles encountered the terrain discontinuities under varying conditions, thereby limiting the analytic utility of their results. However, the tests provided the data necessary for validation of the computer model. Results indicate that passenger cars are less prone to rollover when encountering soil terrain discontinuities in non-tracking maneuvers than are light trucks. However, when a curb is encountered, the smaller passenger car rolled over at a velocity comparable to that of light trucks, while the larger passenger car did not roll over, even when started from significantly higher initial speeds under simulation. The results also support the concept that soil-tripped rollovers and curb-tripped rollovers are qualitatively different events.
{"title":"THE EFFECTS OF LIGHT-VEHICLE DESIGN PARAMETERS IN TRIPPED-ROLLOVER MANEUVERS - A STATISTICAL ANALYSIS USING AN EXPERIMENTALLY VALIDATED COMPUTER MODEL. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"K. L. d’Entremont","doi":"10.4271/950315","DOIUrl":"https://doi.org/10.4271/950315","url":null,"abstract":"In this chapter, from a comprehensive text about occupant and vehicle responses in rollovers, the authors report the results of analyses of single-vehicle-accident, tripped-rollover maneuvers involving either light vehicles from four classes of ground vehicles. All vehicles, except for the passenger cars, were evaluated in both unladen and laden states. The authors note that the vehicles encountered the terrain discontinuities under varying conditions, thereby limiting the analytic utility of their results. However, the tests provided the data necessary for validation of the computer model. Results indicate that passenger cars are less prone to rollover when encountering soil terrain discontinuities in non-tracking maneuvers than are light trucks. However, when a curb is encountered, the smaller passenger car rolled over at a velocity comparable to that of light trucks, while the larger passenger car did not roll over, even when started from significantly higher initial speeds under simulation. The results also support the concept that soil-tripped rollovers and curb-tripped rollovers are qualitatively different events.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128320075","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}
G. J. Heydinger, R A Bixel, W. R. Garrott, M. Pyne, J. G. Howe, D. Guenther
This chapter, from a comprehensive text on occupant and vehicle responses in rollovers, consists primarily of a printed listing of the National Highway Traffic Safety Administration's (NHTSA) Light Vehicle Inertial Parameter Database which cover 496 vehicles. Part one of the listing contains vehicle description and configuration data, plus wheelbase, track width, roof height, weight, and test comments. Part two contains vehicle description and configuration data, C.G. position, moments of inertia, roll/yaw products of inertia, tilt table ratio, and static stability factor data. The authors also offer a brief discussion of the accuracy of inertial measurements, including selected graphs of quantities listed in the database for some of the 1998 model year vehicles tested. Electronic copies of the Light Vehicle Inertial Parameter Database, which also contain Vehicle Identification Numbers (VIN) for the vehicles tested, may be obtained by contact Dr. W.R. Garrott (riley.garrott@nhtsa.dot.gov).
{"title":"MEASURED VEHICLE INERTIAL PARAMETERS - NHTSA'S DATA THROUGH NOVEMBER 1998. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"G. J. Heydinger, R A Bixel, W. R. Garrott, M. Pyne, J. G. Howe, D. Guenther","doi":"10.4271/1999-01-1336","DOIUrl":"https://doi.org/10.4271/1999-01-1336","url":null,"abstract":"This chapter, from a comprehensive text on occupant and vehicle responses in rollovers, consists primarily of a printed listing of the National Highway Traffic Safety Administration's (NHTSA) Light Vehicle Inertial Parameter Database which cover 496 vehicles. Part one of the listing contains vehicle description and configuration data, plus wheelbase, track width, roof height, weight, and test comments. Part two contains vehicle description and configuration data, C.G. position, moments of inertia, roll/yaw products of inertia, tilt table ratio, and static stability factor data. The authors also offer a brief discussion of the accuracy of inertial measurements, including selected graphs of quantities listed in the database for some of the 1998 model year vehicles tested. Electronic copies of the Light Vehicle Inertial Parameter Database, which also contain Vehicle Identification Numbers (VIN) for the vehicles tested, may be obtained by contact Dr. W.R. Garrott (riley.garrott@nhtsa.dot.gov).","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133676961","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}
This paper presents the results of performance characterization testing of the extended-range Conceptor G Van electric vehicle (EV). Testing was performed at the Electrotek Electric Vehicle Test Facility (EVTF) as part of the Electric Power Research Institute (EPRI)/Electrotek EV Program. A 7-kW Onan gasoline engine/generator (E/G) set was retrofitted into the vehicle by McKee Engineering of Lake Zurich, Illinois. It was found that use of the E/G increased driving range significantly for all cases. Additional tests were performed to determine the dc energy consumption of the XREV over the C cycle and at various constant speeds. Data is presented which includes driving test results as well as calculated costs for different combinations of electric and gasoline operation.
{"title":"PERFORMANCE TESTING OF THE EXTENDED-RANGE (HYBRID) ELECTRIC G VAN. IN: ELECTRIC AND HYBRID VEHICLE TECHNOLOGY","authors":"A. S. Keller, G. Whitehead","doi":"10.4271/920439","DOIUrl":"https://doi.org/10.4271/920439","url":null,"abstract":"This paper presents the results of performance characterization testing of the extended-range Conceptor G Van electric vehicle (EV). Testing was performed at the Electrotek Electric Vehicle Test Facility (EVTF) as part of the Electric Power Research Institute (EPRI)/Electrotek EV Program. A 7-kW Onan gasoline engine/generator (E/G) set was retrofitted into the vehicle by McKee Engineering of Lake Zurich, Illinois. It was found that use of the E/G increased driving range significantly for all cases. Additional tests were performed to determine the dc energy consumption of the XREV over the C cycle and at various constant speeds. Data is presented which includes driving test results as well as calculated costs for different combinations of electric and gasoline operation.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130825016","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}
In this chapter, from a comprehensive text about occupant and vehicle responses in rollovers, the authors report on research undertaken to find vehicle characteristics which may contribute to steering maneuver induced rollover accidents. The research used the Vehicle Dynamics Analysis, Non-Linear (VDANL) computer simulation on 28 different steering induced maneuvers for each of 51 vehicles; a total of 292 directional response metrics were computed for each vehicle. Results showed that the vehicle directional response metrics were not good predictors of the observed rollovers per single vehicle accident rate for each make/model of vehicle. Instead, two of the significant variables describe the accident location (whether or not the accident occurred in a rural area and whether or not the accident occurred on a curved section of roadway). The other four significant variables were not obtained from directional response simulation runs. They were: tilt table ratio, the number of single vehicle accidents per thousand registered vehicles, whether or not the vehicles had front wheel drive, and whether or not the vehicle was a sport utility vehicle. The authors conclude that none of the directional response metrics, alone, are good predictors of rollover propensities.
{"title":"AN INVESTIGATION, VIA SIMULATION, OF VEHICLE CHARACTERISTICS THAT CONTRIBUTE TO STEERING MANEUVER INDUCED ROLLOVER. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"W. R. Garrott, G. Heydinger","doi":"10.4271/920585","DOIUrl":"https://doi.org/10.4271/920585","url":null,"abstract":"In this chapter, from a comprehensive text about occupant and vehicle responses in rollovers, the authors report on research undertaken to find vehicle characteristics which may contribute to steering maneuver induced rollover accidents. The research used the Vehicle Dynamics Analysis, Non-Linear (VDANL) computer simulation on 28 different steering induced maneuvers for each of 51 vehicles; a total of 292 directional response metrics were computed for each vehicle. Results showed that the vehicle directional response metrics were not good predictors of the observed rollovers per single vehicle accident rate for each make/model of vehicle. Instead, two of the significant variables describe the accident location (whether or not the accident occurred in a rural area and whether or not the accident occurred on a curved section of roadway). The other four significant variables were not obtained from directional response simulation runs. They were: tilt table ratio, the number of single vehicle accidents per thousand registered vehicles, whether or not the vehicles had front wheel drive, and whether or not the vehicle was a sport utility vehicle. The authors conclude that none of the directional response metrics, alone, are good predictors of rollover propensities.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"333 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132651962","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}
One solution to the need for pollution-free, energy-efficient vehicles is the electric automobile which draws power from rechargeable batteries. There are few of these vehicles on the road today, however, becasue present batteries can store very little energy compared with that of a tank of gasoline. To obtain adequate range, the concept vehicle described here adopts a new battery which can be recharged to 40 percent of capacity in only six minutes. This super quick-charging system makes it possible to recharge the batteries at an electric recharging station just as gasoline-powered vehicles are refilled at service stations. The electric concept vehicle also has improved aerodynamics, reduced rolling resistance and a lighter curb weight, which help assure adequate range.
{"title":"DEVELOPMENT OF AN ELECTRIC CONCEPT VEHICLE WITH A SUPER QUICK CHARGING SYSTEM. IN:ELECTRIC AND HYBRID VEHICLE TECHNOLOGY","authors":"Masato Fukino, N. Irie, Hideo Ito","doi":"10.4271/920442","DOIUrl":"https://doi.org/10.4271/920442","url":null,"abstract":"One solution to the need for pollution-free, energy-efficient vehicles is the electric automobile which draws power from rechargeable batteries. There are few of these vehicles on the road today, however, becasue present batteries can store very little energy compared with that of a tank of gasoline. To obtain adequate range, the concept vehicle described here adopts a new battery which can be recharged to 40 percent of capacity in only six minutes. This super quick-charging system makes it possible to recharge the batteries at an electric recharging station just as gasoline-powered vehicles are refilled at service stations. The electric concept vehicle also has improved aerodynamics, reduced rolling resistance and a lighter curb weight, which help assure adequate range.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"73 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114939104","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}
This paper describes a high-performance ac electric drive system, consisting of a high-efficiency (95 to 97 percent) 70-hp interior permanent magnet (IPM) synchronous motor, an advanced MOS-Controlled Thyristor (MCT)-based three-phase inverter, and microcomputer-based inverter/motor controller. It presents performance and system efficiency test results of the 3-phase MCT inverter and IPM motor (mounted in the test transaxle and coupled to the dynamometer). MCT module tests were run at 204-V, 250-V, and 270-V dc link voltages, while drive system tests were run over the torque-speed plane to characterize the electric drive system for 150-V and 200-V dc link voltages. Test results, include here, show the ETX-II MCT inverter-based electric drive system has 2-3 percentage points higher efficiency than the corresponding ETX-II Darlington inverter-based electric drive, over a significant portion of the torque-speed plane.
{"title":"ETX-II 70 HP MCT INVERTER ELECTRIC DRIVE SYSTEM PERFORMANCE TESTS. IN: ELECTRIC AND HYBRID VEHICLE TECHNOLOGY","authors":"R. King, J. Park, A. W. Clock, D. Watrous","doi":"10.4271/920445","DOIUrl":"https://doi.org/10.4271/920445","url":null,"abstract":"This paper describes a high-performance ac electric drive system, consisting of a high-efficiency (95 to 97 percent) 70-hp interior permanent magnet (IPM) synchronous motor, an advanced MOS-Controlled Thyristor (MCT)-based three-phase inverter, and microcomputer-based inverter/motor controller. It presents performance and system efficiency test results of the 3-phase MCT inverter and IPM motor (mounted in the test transaxle and coupled to the dynamometer). MCT module tests were run at 204-V, 250-V, and 270-V dc link voltages, while drive system tests were run over the torque-speed plane to characterize the electric drive system for 150-V and 200-V dc link voltages. Test results, include here, show the ETX-II MCT inverter-based electric drive system has 2-3 percentage points higher efficiency than the corresponding ETX-II Darlington inverter-based electric drive, over a significant portion of the torque-speed plane.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132316929","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}
This paper summarizes the design of a variable speed Scroll compressor based prototype air conditioning system for an electrically powered mini-van. The system refrigerant is HFC-134a and high performance heat transfer components are utilized. The selected lubricant and special construction materials are discussed.
{"title":"VARIABLE SPEED COMPRESSOR, HFC-134A BASED AIR CONDITIONING SYSTEM FOR ELECTRIC VEHICLES. IN: ELECTRIC AND HYBRID VEHICLE TECHNOLOGY","authors":"J. Dieckmann, D. Mallory","doi":"10.4271/920444","DOIUrl":"https://doi.org/10.4271/920444","url":null,"abstract":"This paper summarizes the design of a variable speed Scroll compressor based prototype air conditioning system for an electrically powered mini-van. The system refrigerant is HFC-134a and high performance heat transfer components are utilized. The selected lubricant and special construction materials are discussed.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127393475","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}
This chapter on the statistical analysis of vehicle rollover propensity and vehicle stability is from a comprehensive textbook on occupant and vehicle responses in rollovers. The author documents the accident data collection, processing, and analysis methodology used by the National Highway Traffic Safety Administration (NHTSA) in a major agency investigation of the rollover propensity of light duty vehicles. These efforts were initiated in response to two petitions for rulemaking requesting the development of a standard for rollover stability. Logistic regression models were used to investigate the ability of a number of stability measures to predict vehicle rollover propensity, while accounting for a number of driver and environmental factors. The results demonstrate the existence of a relationship between measures of roll stability and a vehicle's propensity to roll over in real-world single-vehicle accidents. Of the three basic roll stability metrics evaluated (tilt table ratio, static stability factor, and side pull ratio), the tilt table ratio appeared to provide the greatest explanatory power, but only by a slight margin over the static stability factor.
{"title":"A STATISTICAL ANALYSIS OF VEHICLE ROLLOVER PROPENSITY AND VEHICLE STABILITY. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"T. Klein","doi":"10.4271/920584","DOIUrl":"https://doi.org/10.4271/920584","url":null,"abstract":"This chapter on the statistical analysis of vehicle rollover propensity and vehicle stability is from a comprehensive textbook on occupant and vehicle responses in rollovers. The author documents the accident data collection, processing, and analysis methodology used by the National Highway Traffic Safety Administration (NHTSA) in a major agency investigation of the rollover propensity of light duty vehicles. These efforts were initiated in response to two petitions for rulemaking requesting the development of a standard for rollover stability. Logistic regression models were used to investigate the ability of a number of stability measures to predict vehicle rollover propensity, while accounting for a number of driver and environmental factors. The results demonstrate the existence of a relationship between measures of roll stability and a vehicle's propensity to roll over in real-world single-vehicle accidents. Of the three basic roll stability metrics evaluated (tilt table ratio, static stability factor, and side pull ratio), the tilt table ratio appeared to provide the greatest explanatory power, but only by a slight margin over the static stability factor.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129347862","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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