Pub Date : 2020-08-15DOI: 10.1504/ijvp.2020.10031350
Michael P. Cole, C. Lucas, Kumar B. Kulkarni, Daniel W. Carruth, Christopher R. Hudson, P. Jayakumar, D. Gorsich
Autonomous systems are the future of the Army and Ground Vehicle Systems Center has aligned itself accordingly to support unmanned ground vehicle (UGV) development. Physically testing autonomous algorithms and vehicle systems can be expensive and time consuming, a problem addressed by the use of modelling and simulation (M&S) tools. A multitude of both Government owned and commercial off-the-shelf tools (COTS) are widely available, all claim to virtually evaluate autonomous ground vehicles operating on various environments and scenarios. Most of the COTS tools primarily focus on the commercial automotive industry where vehicles are driven in a structured environment. In this paper two M&S tools, viz., Autonomous Navigation Virtual Environment Laboratory (ANVEL) and rover analysis modelling and simulation (ROAMS) are evaluated for military applications, where the demands for navigation include both on-road and off-road, as well as both structured and unstructured environments as a preliminary benchmark.
{"title":"Quantitative assessment of modelling and simulation tools for autonomous navigation of military vehicles over off-road terrains","authors":"Michael P. Cole, C. Lucas, Kumar B. Kulkarni, Daniel W. Carruth, Christopher R. Hudson, P. Jayakumar, D. Gorsich","doi":"10.1504/ijvp.2020.10031350","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10031350","url":null,"abstract":"Autonomous systems are the future of the Army and Ground Vehicle Systems Center has aligned itself accordingly to support unmanned ground vehicle (UGV) development. Physically testing autonomous algorithms and vehicle systems can be expensive and time consuming, a problem addressed by the use of modelling and simulation (M&S) tools. A multitude of both Government owned and commercial off-the-shelf tools (COTS) are widely available, all claim to virtually evaluate autonomous ground vehicles operating on various environments and scenarios. Most of the COTS tools primarily focus on the commercial automotive industry where vehicles are driven in a structured environment. In this paper two M&S tools, viz., Autonomous Navigation Virtual Environment Laboratory (ANVEL) and rover analysis modelling and simulation (ROAMS) are evaluated for military applications, where the demands for navigation include both on-road and off-road, as well as both structured and unstructured environments as a preliminary benchmark.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46490391","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 : 2020-08-15DOI: 10.1504/ijvp.2020.10031351
Junkui, N. A. Allen, N. Huang, Shervin Shoai Naini, Richard S. Miller, Denise M. Rizzo, K. Sebeck, J. Wagner
Modern autonomous hybrid vehicles are required to have longer range, better fuel economy and operate in diverse climate conditions which challenges cooling system design. This paper examines a heat pipe based thermal management system for the vehicle's powertrain components (electric motors, battery pack, and engine). Mathematical models were developed to describe the components' thermal behavior. Nonlinear controllers were designed to maintain the components' temperatures about their reference values by regulating multiple actuators for minimised temperature fluctuations and energy consumption. Numerical results considered various road grades and ambient conditions to demonstrate the thermal management system robustness. Simulation results show that the component temperatures were successfully maintained about their reference values with a small tracking error using the proposed thermal management system. The findings also show the ability to minimise energy through the integration of heat pipes and smart actuators.
{"title":"Unmanned autonomous ground hybrid vehicle thermal management system: design and control","authors":"Junkui, N. A. Allen, N. Huang, Shervin Shoai Naini, Richard S. Miller, Denise M. Rizzo, K. Sebeck, J. Wagner","doi":"10.1504/ijvp.2020.10031351","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10031351","url":null,"abstract":"Modern autonomous hybrid vehicles are required to have longer range, better fuel economy and operate in diverse climate conditions which challenges cooling system design. This paper examines a heat pipe based thermal management system for the vehicle's powertrain components (electric motors, battery pack, and engine). Mathematical models were developed to describe the components' thermal behavior. Nonlinear controllers were designed to maintain the components' temperatures about their reference values by regulating multiple actuators for minimised temperature fluctuations and energy consumption. Numerical results considered various road grades and ambient conditions to demonstrate the thermal management system robustness. Simulation results show that the component temperatures were successfully maintained about their reference values with a small tracking error using the proposed thermal management system. The findings also show the ability to minimise energy through the integration of heat pipes and smart actuators.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43396364","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 : 2020-04-26DOI: 10.1504/ijvp.2020.10028999
Xiujian Yang, Chuqiao Feng
This paper aims to investigate the equivalent mechanical model of longitudinal fluid sloshing for a partially filled tank vehicle. A one-degree-of-freedom (1DOF) mass-spring-damping (MSD) equivalent mechanical model proposed in the literature is first evaluated. To improve the precision of the MSD model, two 2DOF models those are the serial 2DOF (2DOF-S) model and the parallel 2DOF (2DOF-P) model, and a hybrid 3DOF (3DOF-H) model have been proposed, formulated and evaluated. Comparisons demonstrate that the 3DOF-H model can provide rather satisfying precision in broad ranges of tank ellipticity and fill level. Finally, the proposed 3DOF-H MSD sloshing model is further evaluated from the viewpoint of vehicle dynamics response. It is revealed that it is easy to integrate the 3DOF-H model with vehicle dynamics to build a fluid tank vehicle model which can reflect the basic dynamics property of a tank vehicle.
{"title":"Investigation on the equivalent mechanical longitudinal fluid sloshing model for a partially filled tank vehicle","authors":"Xiujian Yang, Chuqiao Feng","doi":"10.1504/ijvp.2020.10028999","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10028999","url":null,"abstract":"This paper aims to investigate the equivalent mechanical model of longitudinal fluid sloshing for a partially filled tank vehicle. A one-degree-of-freedom (1DOF) mass-spring-damping (MSD) equivalent mechanical model proposed in the literature is first evaluated. To improve the precision of the MSD model, two 2DOF models those are the serial 2DOF (2DOF-S) model and the parallel 2DOF (2DOF-P) model, and a hybrid 3DOF (3DOF-H) model have been proposed, formulated and evaluated. Comparisons demonstrate that the 3DOF-H model can provide rather satisfying precision in broad ranges of tank ellipticity and fill level. Finally, the proposed 3DOF-H MSD sloshing model is further evaluated from the viewpoint of vehicle dynamics response. It is revealed that it is easy to integrate the 3DOF-H model with vehicle dynamics to build a fluid tank vehicle model which can reflect the basic dynamics property of a tank vehicle.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41704578","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 : 2020-04-26DOI: 10.1504/ijvp.2020.10029002
Huiyong Zhao, Zhang Guangde, Wang Baohua, He Yuping, Lin Zhao
In a steering process, the steering-motor of a steer-by-wire (SBW) vehicle consumes energy. To facilitate energy efficiency analyses, the steeringmotor energy consumption is split into two parts, which correspond to varied and constant steering-wheel angle operating condition, respectively. The former condition is a vehicle operational manoeuvre, in which steering-wheel angle varies continuously, whereas the latter is a constant-radius circular-curve negotiation, in which steering-wheel angle maintains constant. Analysing the relation of steering-wheel angle with a road curvature, we propose an energysaving strategy for steering-motors of SBW vehicles. The energy-saving strategy is featured with a concept, a hydro-mechanical locking device, and an SBW controller for the steering-motor unit. The feasibility and effectiveness of the energy-saving strategy is demonstrated using closed-loop simulations. To implement the closed-loop simulation, we combine the driver, vehicle, and curved road models generated in CarSim software with the steering-motor model and the SBW controller developed in Matlab/Simulink.
{"title":"An energy-saving strategy for steering-motors of steer-by-wire vehicles","authors":"Huiyong Zhao, Zhang Guangde, Wang Baohua, He Yuping, Lin Zhao","doi":"10.1504/ijvp.2020.10029002","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10029002","url":null,"abstract":"In a steering process, the steering-motor of a steer-by-wire (SBW) vehicle consumes energy. To facilitate energy efficiency analyses, the steeringmotor energy consumption is split into two parts, which correspond to varied and constant steering-wheel angle operating condition, respectively. The former condition is a vehicle operational manoeuvre, in which steering-wheel angle varies continuously, whereas the latter is a constant-radius circular-curve negotiation, in which steering-wheel angle maintains constant. Analysing the relation of steering-wheel angle with a road curvature, we propose an energysaving strategy for steering-motors of SBW vehicles. The energy-saving strategy is featured with a concept, a hydro-mechanical locking device, and an SBW controller for the steering-motor unit. The feasibility and effectiveness of the energy-saving strategy is demonstrated using closed-loop simulations. To implement the closed-loop simulation, we combine the driver, vehicle, and curved road models generated in CarSim software with the steering-motor model and the SBW controller developed in Matlab/Simulink.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47799120","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 : 2020-04-26DOI: 10.1504/ijvp.2020.10028993
P. Yadav, Suprakash Gupta, Deepak Kumar
Dump trucks are one of the widely used and capital-intensive heavy earth moving equipment in the mining industry. Continuous monitoring of dump trucks' performance is essential for a mining system and it needs a well-defined performance measure (PM). This research proposes a PM which is derived from the overall equipment effectiveness (OEE) through modification of performance metrics. Commonly used PMs are based on the internal losses calculation and neglect the operational effect beyond the system boundary, i.e., external losses. The proposed PM presents an approach that unites time performance, capacity performance as well as environmental performance. It has been illustrated with a case study in a large surface coal mine and the findings are useful to decision making.
{"title":"Measurement and analysis of performance of mining dump trucks","authors":"P. Yadav, Suprakash Gupta, Deepak Kumar","doi":"10.1504/ijvp.2020.10028993","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10028993","url":null,"abstract":"Dump trucks are one of the widely used and capital-intensive heavy earth moving equipment in the mining industry. Continuous monitoring of dump trucks' performance is essential for a mining system and it needs a well-defined performance measure (PM). This research proposes a PM which is derived from the overall equipment effectiveness (OEE) through modification of performance metrics. Commonly used PMs are based on the internal losses calculation and neglect the operational effect beyond the system boundary, i.e., external losses. The proposed PM presents an approach that unites time performance, capacity performance as well as environmental performance. It has been illustrated with a case study in a large surface coal mine and the findings are useful to decision making.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41936544","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 : 2020-04-26DOI: 10.1504/ijvp.2020.10028995
Smitha Vempaty, Yuping He, Lin Zhao
This paper reviews the state-of-the-art control schemes for enhancing the lateral stability of car-trailer (CT) combinations. Various studies have been conducted on lateral stability control of single-unit vehicles, e.g., cars. However, much less attention has been paid to lateral stability control of multi-unit vehicles, e.g., CT, which usually exhibit poor manoeuvrability in curved-path negotiations and low lateral stability under high-speed evasive manoeuvres. The low lateral stability may lead to unstable motion modes, e.g., trailer-sway and jackknifing, causing severe accidents. To improve the lateral stability, various control schemes were designed considering relevant performance measures and evaluated using either numerical simulations or testing methods. Thus, the topics surveyed in this paper include: directional performance measures, evaluation methods, important parameters affecting the directional performance, and active control approaches for CT combinations. Important control schemes are emphasised and their features discussed and analysed. As a result of the overview, future research efforts are identified.
{"title":"An overview of control schemes for improving the lateral stability of car-trailer combinations","authors":"Smitha Vempaty, Yuping He, Lin Zhao","doi":"10.1504/ijvp.2020.10028995","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10028995","url":null,"abstract":"This paper reviews the state-of-the-art control schemes for enhancing the lateral stability of car-trailer (CT) combinations. Various studies have been conducted on lateral stability control of single-unit vehicles, e.g., cars. However, much less attention has been paid to lateral stability control of multi-unit vehicles, e.g., CT, which usually exhibit poor manoeuvrability in curved-path negotiations and low lateral stability under high-speed evasive manoeuvres. The low lateral stability may lead to unstable motion modes, e.g., trailer-sway and jackknifing, causing severe accidents. To improve the lateral stability, various control schemes were designed considering relevant performance measures and evaluated using either numerical simulations or testing methods. Thus, the topics surveyed in this paper include: directional performance measures, evaluation methods, important parameters affecting the directional performance, and active control approaches for CT combinations. Important control schemes are emphasised and their features discussed and analysed. As a result of the overview, future research efforts are identified.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42625112","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 : 2020-04-26DOI: 10.1504/ijvp.2020.10029000
Chunxiao Hao, Yunshan Ge, Xin Wang
This paper devoted to a comparison of fuel consumption of a diesel engine fuelled with diesel and biodiesel. Comparisons were conducted at sea level, 1600 m and 3300 m. A 6.7L, six cylinder turbocharged heavy-duty diesel engine was introduced. The brake specific fuel consumption (BSFC) over the full engine map were measured and plotted. The results indicated that the fuel consumption with diesel fuelling increased with altitude in all the operating conditions except high-speed, high-load mode; while the fuel consumption with biodiesel fuelling mainly increased with altitude under low-speed, low-load and middle-speed, low-load conditions. Under most of the testing conditions, the fuel consumption with biodiesel fuelling was insensitive to the change of altitude. The comparison of fuel consumption between diesel and biodiesel fuelling demonstrated that diesel was still the more economic option for diesel engines operating at sea level. However, biodiesel fuelling could provide a better fuel economy under middle-speed conditions at high altitudes, particularly at 3300 m.
{"title":"Heavy-duty diesel engine fuel consumption comparison with diesel and biodiesel measured at different altitudes","authors":"Chunxiao Hao, Yunshan Ge, Xin Wang","doi":"10.1504/ijvp.2020.10029000","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10029000","url":null,"abstract":"This paper devoted to a comparison of fuel consumption of a diesel engine fuelled with diesel and biodiesel. Comparisons were conducted at sea level, 1600 m and 3300 m. A 6.7L, six cylinder turbocharged heavy-duty diesel engine was introduced. The brake specific fuel consumption (BSFC) over the full engine map were measured and plotted. The results indicated that the fuel consumption with diesel fuelling increased with altitude in all the operating conditions except high-speed, high-load mode; while the fuel consumption with biodiesel fuelling mainly increased with altitude under low-speed, low-load and middle-speed, low-load conditions. Under most of the testing conditions, the fuel consumption with biodiesel fuelling was insensitive to the change of altitude. The comparison of fuel consumption between diesel and biodiesel fuelling demonstrated that diesel was still the more economic option for diesel engines operating at sea level. However, biodiesel fuelling could provide a better fuel economy under middle-speed conditions at high altitudes, particularly at 3300 m.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41591440","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 : 2020-01-14DOI: 10.1504/ijvp.2020.10026219
S. Rakheja, K. Dewangan, R. Dong, P. Marcotte
In the framework of whole-body vibration (WBV), biodynamics refers to biomechanical responses of the human body to impressed oscillatory forces or motions. The biodynamic responses of the human body to WBV form an essential basis for an understanding of mechanical-equivalent properties of the body and potential injury mechanisms, developments in frequency-weightings and design tools of systems coupled with the human operator. In this first part, the biodynamic responses obtained experimentally in terms of to-the-body and through-the-body functions, are critically reviewed and discussed to highlight influences of various contributory factors, such as those related to posture, body support, anthropometry and nature of vibration, together with the range of experimental conditions. The reported data invariably show highly complex, nonlinear and coupled effects of the majority of the contributory factors. It is shown that the reported studies often conclude conflicting effects of many factors, such as posture, gender, vibration and support conditions.
{"title":"Whole-body vibration biodynamics - a critical review: I. Experimental biodynamics","authors":"S. Rakheja, K. Dewangan, R. Dong, P. Marcotte","doi":"10.1504/ijvp.2020.10026219","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10026219","url":null,"abstract":"In the framework of whole-body vibration (WBV), biodynamics refers to biomechanical responses of the human body to impressed oscillatory forces or motions. The biodynamic responses of the human body to WBV form an essential basis for an understanding of mechanical-equivalent properties of the body and potential injury mechanisms, developments in frequency-weightings and design tools of systems coupled with the human operator. In this first part, the biodynamic responses obtained experimentally in terms of to-the-body and through-the-body functions, are critically reviewed and discussed to highlight influences of various contributory factors, such as those related to posture, body support, anthropometry and nature of vibration, together with the range of experimental conditions. The reported data invariably show highly complex, nonlinear and coupled effects of the majority of the contributory factors. It is shown that the reported studies often conclude conflicting effects of many factors, such as posture, gender, vibration and support conditions.","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43107106","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 : 2020-01-01DOI: 10.1504/ijvp.2020.10031347
Sheng Su, Yitu Lai, Chunxiao Hao, Pan Hou, T. Lv, Yunshan Ge
{"title":"Review of rapid ageing testing methods of three-way catalyst for gasoline engine","authors":"Sheng Su, Yitu Lai, Chunxiao Hao, Pan Hou, T. Lv, Yunshan Ge","doi":"10.1504/ijvp.2020.10031347","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10031347","url":null,"abstract":"","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66689750","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 : 2020-01-01DOI: 10.1504/ijvp.2020.10031353
Gurubasavaraju Tharehallimata, Vijay Mokenapalli
{"title":"Transverse dynamic analysis of semi-active quarter car model controlled with an optimal conventional controller","authors":"Gurubasavaraju Tharehallimata, Vijay Mokenapalli","doi":"10.1504/ijvp.2020.10031353","DOIUrl":"https://doi.org/10.1504/ijvp.2020.10031353","url":null,"abstract":"","PeriodicalId":52169,"journal":{"name":"International Journal of Vehicle Performance","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66689786","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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