Topology optimization has helped make great strides in structural design engineering and should also be applied to nonlinear fields such as determining crashworthiness of vehicles. This paper, by using a homogenization-based density method, develops an X-frame, optimized structural design technique based on crash simulation and an analytical mathematical model. The technique is capable of capturing large deformation of mild steel and thin-walled, viscoelastoplastic buckling through optimality criteria and constraints of mass.
{"title":"CRASHWORTHINESS TOPOLOGY OPTIMIZATION: WITH X-FRAME AND DEFORMATION DECOMPOSITION BASED ON HOMOGENIZED-DENSITY METHOD. IN: CAE METHODS FOR VEHICLE CRASHWORTHINESS AND OCCUPANT SAFETY, AND SAFETY-CRITICAL SYSTEMS","authors":"Y. Jeong","doi":"10.4271/2004-01-1176","DOIUrl":"https://doi.org/10.4271/2004-01-1176","url":null,"abstract":"Topology optimization has helped make great strides in structural design engineering and should also be applied to nonlinear fields such as determining crashworthiness of vehicles. This paper, by using a homogenization-based density method, develops an X-frame, optimized structural design technique based on crash simulation and an analytical mathematical model. The technique is capable of capturing large deformation of mild steel and thin-walled, viscoelastoplastic buckling through optimality criteria and constraints of mass.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124168505","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}
E. Bernal, J. Cuartero, C. Nuez, A. Miravete, L. Castejón
In this paper, new advances in simulation of composite materials under crash loads are applied to the analysis of a car frontal crash structure. Experimental results are used to calibrate constitutive material models and simulation procedures to obtain more accurate representation of material behavior under crash loading. These advanced computational techniques are then applied to crash simulations of components. The front longitudinal beam studied herein is analyzed for 2 load cases: frontal and lateral crash. Qualitative results on specific energy absorption, as well as the absolute energy absorbed by the structure, are especially relevant. Results of simulations of the structure in carbon and glass fibers are presented and compared, focusing on the absolute energy absorbed and specific energy absorption of the structure.
{"title":"ADVANCES IN THE CRASH SIMULATION OF VEHICLE FRONTAL CRASH STRUCTURES MADE OF BRAIDED COMPOSITE MATERIALS. IN: CAE METHODS FOR VEHICLE CRASHWORTHINESS AND OCCUPANT SAFETY, AND SAFETY-CRITICAL SYSTEMS","authors":"E. Bernal, J. Cuartero, C. Nuez, A. Miravete, L. Castejón","doi":"10.4271/2004-01-1175","DOIUrl":"https://doi.org/10.4271/2004-01-1175","url":null,"abstract":"In this paper, new advances in simulation of composite materials under crash loads are applied to the analysis of a car frontal crash structure. Experimental results are used to calibrate constitutive material models and simulation procedures to obtain more accurate representation of material behavior under crash loading. These advanced computational techniques are then applied to crash simulations of components. The front longitudinal beam studied herein is analyzed for 2 load cases: frontal and lateral crash. Qualitative results on specific energy absorption, as well as the absolute energy absorbed by the structure, are especially relevant. Results of simulations of the structure in carbon and glass fibers are presented and compared, focusing on the absolute energy absorbed and specific energy absorption of the structure.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129694471","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}
As traditional mechanical vehicle components evolve into electronic and electro-mechanical systems, the suppliers of these systems must reevaluate their development processes. The aim is to ensure these new products are robust and meet reliability and safety requirements. With these issues in mind, this paper looks at the development of the SmartPark Electronic Parking Brake Technology, which consists of a cable puller type actuator, a conduit reaction style cable system, and an electronic control unit. The system development process, including functional and safety requirements, and design validation are discussed.
{"title":"ELECTRONIC PARKING BRAKE: SIMPLE LEVER TO SAFETY CRITICAL SYSTEM. IN: CAE METHODS FOR VEHICLE CRASHWORTHINESS AND OCCUPANT SAFETY, AND SAFETY-CRITICAL SYSTEMS","authors":"S. Perkins","doi":"10.4271/2004-01-1732","DOIUrl":"https://doi.org/10.4271/2004-01-1732","url":null,"abstract":"As traditional mechanical vehicle components evolve into electronic and electro-mechanical systems, the suppliers of these systems must reevaluate their development processes. The aim is to ensure these new products are robust and meet reliability and safety requirements. With these issues in mind, this paper looks at the development of the SmartPark Electronic Parking Brake Technology, which consists of a cable puller type actuator, a conduit reaction style cable system, and an electronic control unit. The system development process, including functional and safety requirements, and design validation are discussed.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121801701","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 research investigates and analyzes the concept of "shared redundancy" and its application to the design of architectures that integrate multiple safety/mission critical functions or subsystems. The analysis is based on considering different design alternatives with varying levels of physical redundancy of the components constituting the functions or subsystems. Under a set of assumptions, the authors show that overall system reliability and availability in a shared redundancy based-architecture can be improved without increasing the levels of physical redundancy for the components employed at the subsystem level. However, such an improvement will be limited by the component(s) with the minimal level of redundancy.
{"title":"ASSESSING REQUIRED LEVELS OF REDUNDANCY FOR COMPOSITE SAFETY/MISSION CRITICAL SYSTEMS. IN: CAE METHODS FOR VEHICLE CRASHWORTHINESS AND OCCUPANT SAFETY, AND SAFETY-CRITICAL SYSTEMS","authors":"R. Debouk, J. Wysocki","doi":"10.4271/2004-01-1664","DOIUrl":"https://doi.org/10.4271/2004-01-1664","url":null,"abstract":"This research investigates and analyzes the concept of \"shared redundancy\" and its application to the design of architectures that integrate multiple safety/mission critical functions or subsystems. The analysis is based on considering different design alternatives with varying levels of physical redundancy of the components constituting the functions or subsystems. Under a set of assumptions, the authors show that overall system reliability and availability in a shared redundancy based-architecture can be improved without increasing the levels of physical redundancy for the components employed at the subsystem level. However, such an improvement will be limited by the component(s) with the minimal level of redundancy.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132100192","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 discusses functional safety from a car manufacturer's vantage point. Typical elements of a safety standard concerning safety activities during the product development process are described, as well as management and other supporting processes. Special emphasis is given to the aspect of risk assessment and to the determination of safety classes. Experiences with methods for safety analysis such as FTA or FMEA are discussed, and pros and cons of quantitative safety assessment are argued.
{"title":"HOW TO ACHIEVE FUNCTIONAL SAFETY AND WHAT SAFETY STANDARDS AND RISK ASSESSMENT CAN CONTRIBUTE. IN: CAE METHODS FOR VEHICLE CRASHWORTHINESS AND OCCUPANT SAFETY, AND SAFETY-CRITICAL SYSTEMS","authors":"M. Woltereck, Christopher Jung, G. Reichart","doi":"10.4271/2004-01-1662","DOIUrl":"https://doi.org/10.4271/2004-01-1662","url":null,"abstract":"This paper discusses functional safety from a car manufacturer's vantage point. Typical elements of a safety standard concerning safety activities during the product development process are described, as well as management and other supporting processes. Special emphasis is given to the aspect of risk assessment and to the determination of safety classes. Experiences with methods for safety analysis such as FTA or FMEA are discussed, and pros and cons of quantitative safety assessment are argued.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123925684","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}
Mathematical models in combination with mechanical tests were used to develop a frontal crash sensing system and algorithm. The required sensor closure time for the initiation of driver side airbag deployment was estimated by means of multi-body dynamic occupant models. The crash sensing system and algorithm were developed using predictions from a finite element model of the front structure of a passenger vehicle. All models were validated by mechanical tests. Generally good agreement was obtained from the model predictions and results from the mechanical tests.
{"title":"CRASH SENSING AND ALGORITHM DEVELOPMENT FOR FRONTAL AIRBAG SYSTEMS USING CAE METHODS AND MECHANICAL TESTS. IN: CAE METHODS FOR VEHICLE CRASHWORTHINESS AND OCCUPANT SAFETY, AND SAFETY-CRITICAL SYSTEMS","authors":"B. Pipkorn","doi":"10.4271/2004-01-1633","DOIUrl":"https://doi.org/10.4271/2004-01-1633","url":null,"abstract":"Mathematical models in combination with mechanical tests were used to develop a frontal crash sensing system and algorithm. The required sensor closure time for the initiation of driver side airbag deployment was estimated by means of multi-body dynamic occupant models. The crash sensing system and algorithm were developed using predictions from a finite element model of the front structure of a passenger vehicle. All models were validated by mechanical tests. Generally good agreement was obtained from the model predictions and results from the mechanical tests.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"2013 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130827589","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}
E. Moffatt, Eddie Cooper, J. Croteau, K. Orlowski, Debora R. Marth, J. Carter
The authors of this chapter, from a comprehensive text on occupant and vehicle responses in rollovers, report on a study of three rollcaged and three production roof vehicles were exposed to matched-pair rollover impacts using the Controlled Rollover Impact System (CRIS). The CRIS consists of a towed semi-trailer, which suspends and drops a rotating vehicle from a support frame on the rear of the trailer. The authors found that the roof-to-ground contacts were representative of severe impacts in previous rollover testing and real world rollovers. Results showed that the seat-belted dummies measured nearly identical head impacts and neck loads, with or without the rollcage, despite significant roof crush in the production roof vehicles. The peak head accelerations and neck loads were a result of the roof striking the ground and stopping and were not related to roof/pillar deformation. If humans were subjected to these same impact conditions, the rollcaged vehicles would not have protected them. The authors conclude that the CRIS is a very reliable tool to conduct repeatable rollover impacts with controlled dummy positioning.
{"title":"MATCHED-PAIR ROLLOVER IMPACTS OF ROLLCAGED AND PRODUCTION ROOF CARS USING THE CONTROLLED ROLLOVER IMPACT SYSTEM (CRIS). IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"E. Moffatt, Eddie Cooper, J. Croteau, K. Orlowski, Debora R. Marth, J. Carter","doi":"10.4271/2003-01-0172","DOIUrl":"https://doi.org/10.4271/2003-01-0172","url":null,"abstract":"The authors of this chapter, from a comprehensive text on occupant and vehicle responses in rollovers, report on a study of three rollcaged and three production roof vehicles were exposed to matched-pair rollover impacts using the Controlled Rollover Impact System (CRIS). The CRIS consists of a towed semi-trailer, which suspends and drops a rotating vehicle from a support frame on the rear of the trailer. The authors found that the roof-to-ground contacts were representative of severe impacts in previous rollover testing and real world rollovers. Results showed that the seat-belted dummies measured nearly identical head impacts and neck loads, with or without the rollcage, despite significant roof crush in the production roof vehicles. The peak head accelerations and neck loads were a result of the roof striking the ground and stopping and were not related to roof/pillar deformation. If humans were subjected to these same impact conditions, the rollcaged vehicles would not have protected them. The authors conclude that the CRIS is a very reliable tool to conduct repeatable rollover impacts with controlled dummy positioning.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129312862","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. Forkenbrock, W. R. Garrott, M. Heitz, Bryan C. O'Harra
In this chapter, from a comprehensive text about occupant and vehicle responses in rollovers, the authors report on an experimental examination of J-turn and fishhook maneuvers that may induce on-road, untripped, light vehicle rollover. This chapter is the first of two papers on the research used to develop dynamic maneuver tests for rollover resistance ratings. This research was part of the National Highway Traffic Safety Administration's (NHTSA) rollover research program (2001). In this phase of research, five characterization maneuvers and eight rollover resistance maneuvers were evaluated and assigned a rating of Excellent, Good, Satisfactory, Bad, or Very Bad. This chapter offers an analysis of one characterization maneuver (the Slowly Increasing Steer maneuver) and four Rollover Resistance maneuvers (the NHTSA J-Turn, Fishhook 1a, Fishhook 1b, and Nissan fishhook). Results determined that each of these maneuvers has a rating of satisfactory or better in each of the maneuver evaluation factors (objectivity and repeatability, performability, discriminatory capability, and appearance of reality). The authors rated Fishhook 1b the best overall; however, since the NHTSA J-Turn is the most basic of potential maneuvers, they feel it serves as a useful complement to Fishhook 1b.
{"title":"AN EXPERIMENTAL EXAMINATION OF J-TURN AND FISHHOOK MANEUVERS THAT MAY INDUCE ON-ROAD, UNTRIPPED, LIGHT VEHICLE ROLLOVER. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"G. Forkenbrock, W. R. Garrott, M. Heitz, Bryan C. O'Harra","doi":"10.4271/2003-01-1008","DOIUrl":"https://doi.org/10.4271/2003-01-1008","url":null,"abstract":"In this chapter, from a comprehensive text about occupant and vehicle responses in rollovers, the authors report on an experimental examination of J-turn and fishhook maneuvers that may induce on-road, untripped, light vehicle rollover. This chapter is the first of two papers on the research used to develop dynamic maneuver tests for rollover resistance ratings. This research was part of the National Highway Traffic Safety Administration's (NHTSA) rollover research program (2001). In this phase of research, five characterization maneuvers and eight rollover resistance maneuvers were evaluated and assigned a rating of Excellent, Good, Satisfactory, Bad, or Very Bad. This chapter offers an analysis of one characterization maneuver (the Slowly Increasing Steer maneuver) and four Rollover Resistance maneuvers (the NHTSA J-Turn, Fishhook 1a, Fishhook 1b, and Nissan fishhook). Results determined that each of these maneuvers has a rating of satisfactory or better in each of the maneuver evaluation factors (objectivity and repeatability, performability, discriminatory capability, and appearance of reality). The authors rated Fishhook 1b the best overall; however, since the NHTSA J-Turn is the most basic of potential maneuvers, they feel it serves as a useful complement to Fishhook 1b.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129723484","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}
Rollover crashes are an important issue in automobile safety. Currently, the safety community is not only working on advancing injury countermeasures but is also investigating technologies to help avoid rollover crashes. This chapter on a vehicle test that simulates real-world conditions is from a comprehensive textbook on occupant and vehicle responses in rollovers. The authors note that the evaluation of rollovers typically involves vehicle-handling tests that are conducted on flat road surfaces with a uniform or split coefficient of friction. They stress that it is crucial to determine the precipitating events leading to rollovers by analyzing real-world rollover crashes. The authors determined the sequence of events leading to rollovers in 63 investigated cases. The cases were divided into 3 categories defining the precipitating event leading to a rollover: negotiating a curve at usually too high a speed (47%), drifting off the road (27%), and avoiding an obstacle in the traveling lane (25%). This study prioritizes the need to carry out tests that simulate a vehicle leaving the road and having at least two wheels on the shoulder after any of these three precipitating events (90 percent of the 63 cases involved the vehicle leaving the roadway with at least 2 wheels). The authors conclude that handling tests need to include a transition from a road surface to the shoulder where there may be a drop off of approximately 50 mm and an attempt to recover back onto the road with various degrees of steering and braking.
{"title":"CASE STUDY OF VEHICLE MANEUVERS LEADING TO ROLLOVERS: NEED FOR A VEHICLE TEST SIMULATING OFF-ROAD EXCURSIONS, RECOVERY AND HANDLING. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS","authors":"D. Viano, C. Parenteau","doi":"10.4271/2003-01-0169","DOIUrl":"https://doi.org/10.4271/2003-01-0169","url":null,"abstract":"Rollover crashes are an important issue in automobile safety. Currently, the safety community is not only working on advancing injury countermeasures but is also investigating technologies to help avoid rollover crashes. This chapter on a vehicle test that simulates real-world conditions is from a comprehensive textbook on occupant and vehicle responses in rollovers. The authors note that the evaluation of rollovers typically involves vehicle-handling tests that are conducted on flat road surfaces with a uniform or split coefficient of friction. They stress that it is crucial to determine the precipitating events leading to rollovers by analyzing real-world rollover crashes. The authors determined the sequence of events leading to rollovers in 63 investigated cases. The cases were divided into 3 categories defining the precipitating event leading to a rollover: negotiating a curve at usually too high a speed (47%), drifting off the road (27%), and avoiding an obstacle in the traveling lane (25%). This study prioritizes the need to carry out tests that simulate a vehicle leaving the road and having at least two wheels on the shoulder after any of these three precipitating events (90 percent of the 63 cases involved the vehicle leaving the roadway with at least 2 wheels). The authors conclude that handling tests need to include a transition from a road surface to the shoulder where there may be a drop off of approximately 50 mm and an attempt to recover back onto the road with various degrees of steering and braking.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124782202","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 examines the efforts of European car manufacturers and suppliers to seek solutions to meets pedestrian safety requirements set forth by the European Union (EU) that all member countries must meet starting in July 2005. To fulfill these requirements, numerous active and passive concepts are investigated in addition to many other limitations imposed on the front end of the car, all of which deal with energy absorption. The paper introduces an approach to achieving a passive solution for the development of a "virtual Stiffness Profile" to help identify the optimum balance of engineering and styling to meet the EU requirements.
{"title":"THE VIRTUAL STIFFNESS PROFILE - A DESIGN METHODOLOGY FOR PEDESTRIAN SAFETY. IN: PEDESTRIAN SAFETY","authors":"A. Droste, P. Naughton, Peter Cate","doi":"10.4271/2002-01-2119","DOIUrl":"https://doi.org/10.4271/2002-01-2119","url":null,"abstract":"This paper examines the efforts of European car manufacturers and suppliers to seek solutions to meets pedestrian safety requirements set forth by the European Union (EU) that all member countries must meet starting in July 2005. To fulfill these requirements, numerous active and passive concepts are investigated in addition to many other limitations imposed on the front end of the car, all of which deal with energy absorption. The paper introduces an approach to achieving a passive solution for the development of a \"virtual Stiffness Profile\" to help identify the optimum balance of engineering and styling to meet the EU requirements.","PeriodicalId":291036,"journal":{"name":"Publication of: Society of Automotive Engineers","volume":"67 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120858479","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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