Pub Date : 2019-08-01DOI: 10.1109/COASE.2019.8843219
S. Goecke, T. Seefeld, D. Tyralla, A. Krug
Ultra high strength steels UHSS are increasingly used in dynamic highly stressed constructions such as mobile crane booms to realise light weight designs with highest maximum loads. To guaranty sufficient mechanical-technological joint properties in welded joint, the monitoring and control of the cooling times is required. Hence, in this work, a challenging approach is the accurate in-situ and real-time sensing of the energy input in MAG laser hybrid welding of UHSS processed by sophisticated IR thermography sensors for robust “zero-defect manufacturing”.
{"title":"Monitoring and Control of the Heat Input in MAG-Laser-Hybrid Welding of High Strength Steel in Telescopic Crane Booms","authors":"S. Goecke, T. Seefeld, D. Tyralla, A. Krug","doi":"10.1109/COASE.2019.8843219","DOIUrl":"https://doi.org/10.1109/COASE.2019.8843219","url":null,"abstract":"Ultra high strength steels UHSS are increasingly used in dynamic highly stressed constructions such as mobile crane booms to realise light weight designs with highest maximum loads. To guaranty sufficient mechanical-technological joint properties in welded joint, the monitoring and control of the cooling times is required. Hence, in this work, a challenging approach is the accurate in-situ and real-time sensing of the energy input in MAG laser hybrid welding of UHSS processed by sophisticated IR thermography sensors for robust “zero-defect manufacturing”.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"108 1","pages":"1744-1747"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81314486","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 : 2019-08-01DOI: 10.1109/COASE.2019.8842957
Siyang Gao, Jianzhong Du, Chun-Hung Chen
In this research, we consider the ranking and selection problem in the presence of covariates. It is an important problem in personalized decision making. The performance of each design alternative depends on the values of the covariates to the simulation model for which the relationship is hard to describe analytically. Therefore the optimal design under each possible covariate value needs to be estimated by simulation. This work first introduces three measures to evaluate the selection quality over the covariate space and investigates their rate functions of convergence. By optimizing the rate functions, an asymptotically optimal budget allocation rule is developed and a corresponding selection algorithm is devised. We further show that the selection algorithm can recover the asymptotical optimal allocation in the limit. The high efficiency of the selection algorithm is illustrated via numerical testing.
{"title":"Selecting the Optimal System Design under Covariates","authors":"Siyang Gao, Jianzhong Du, Chun-Hung Chen","doi":"10.1109/COASE.2019.8842957","DOIUrl":"https://doi.org/10.1109/COASE.2019.8842957","url":null,"abstract":"In this research, we consider the ranking and selection problem in the presence of covariates. It is an important problem in personalized decision making. The performance of each design alternative depends on the values of the covariates to the simulation model for which the relationship is hard to describe analytically. Therefore the optimal design under each possible covariate value needs to be estimated by simulation. This work first introduces three measures to evaluate the selection quality over the covariate space and investigates their rate functions of convergence. By optimizing the rate functions, an asymptotically optimal budget allocation rule is developed and a corresponding selection algorithm is devised. We further show that the selection algorithm can recover the asymptotical optimal allocation in the limit. The high efficiency of the selection algorithm is illustrated via numerical testing.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"33 1","pages":"547-552"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81335571","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 : 2019-08-01DOI: 10.1109/COASE.2019.8843052
Chao-Bo Yan
Since the high energy consumption is prominent in production systems, reducing the energy consumption is of great significance. In this paper, the energy consumption optimization problem in a two-machine Bernoulli line with general lowerand upper-bounds of machine efficiencies is investigated. Specifically, the problem is formulated as a constrained nonlinear programming; taking advantage of existing results of the optimization model without additional limits on machine efficiencies, the structure of the feasible region and properties of the objective function on the feasible region are analyzed; based on the structure of the feasible region and properties of the objective function obtained, a method is developed to solve the energy consumption optimization problem in the two-machine Bernoulli line with general limits on machine efficiencies.
{"title":"Energy Consumption optimization in Two-Machine Bernoulli Serial Lines with Limits on Machine Efficiency","authors":"Chao-Bo Yan","doi":"10.1109/COASE.2019.8843052","DOIUrl":"https://doi.org/10.1109/COASE.2019.8843052","url":null,"abstract":"Since the high energy consumption is prominent in production systems, reducing the energy consumption is of great significance. In this paper, the energy consumption optimization problem in a two-machine Bernoulli line with general lowerand upper-bounds of machine efficiencies is investigated. Specifically, the problem is formulated as a constrained nonlinear programming; taking advantage of existing results of the optimization model without additional limits on machine efficiencies, the structure of the feasible region and properties of the objective function on the feasible region are analyzed; based on the structure of the feasible region and properties of the objective function obtained, a method is developed to solve the energy consumption optimization problem in the two-machine Bernoulli line with general limits on machine efficiencies.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"26 1","pages":"85-90"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81430172","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 : 2019-08-01DOI: 10.1109/COASE.2019.8843116
Daniel Ahlers, Florens Wasserfall, N. Hendrich, Jianwei Zhang
Additive manufacturing processes are inherently subject to discretization effects. For most technologies, stairstepping artifacts impair the surface quality of 3D printed objects, especially when the surface slope is close to horizontal.In this paper we propose a novel Fused Deposition Modeling (FDM) slicing approach that combines nonplanar and planar layers, increasing printing quality and resulting in smoother, stronger object surfaces. Our slicing algorithm automatically detects which parts of the object should be printed with nonplanar layers and uses a geometric model of the printhead and extruder to generate collision-free toolpaths.Our open source implementation is based on the popular Slic3r tool and can be used on all common three-axis 3D printers. We present typical printing results and compare surface quality as well as slicing and printing times with traditional and adaptive planar slicing.
{"title":"3D Printing of Nonplanar Layers for Smooth Surface Generation","authors":"Daniel Ahlers, Florens Wasserfall, N. Hendrich, Jianwei Zhang","doi":"10.1109/COASE.2019.8843116","DOIUrl":"https://doi.org/10.1109/COASE.2019.8843116","url":null,"abstract":"Additive manufacturing processes are inherently subject to discretization effects. For most technologies, stairstepping artifacts impair the surface quality of 3D printed objects, especially when the surface slope is close to horizontal.In this paper we propose a novel Fused Deposition Modeling (FDM) slicing approach that combines nonplanar and planar layers, increasing printing quality and resulting in smoother, stronger object surfaces. Our slicing algorithm automatically detects which parts of the object should be printed with nonplanar layers and uses a geometric model of the printhead and extruder to generate collision-free toolpaths.Our open source implementation is based on the popular Slic3r tool and can be used on all common three-axis 3D printers. We present typical printing results and compare surface quality as well as slicing and printing times with traditional and adaptive planar slicing.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"86 1","pages":"1737-1743"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88201377","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 : 2019-08-01DOI: 10.1109/COASE.2019.8842913
Marius Oei, Y. Klett, Nadine Harder, D. Flemming, O. Sawodny
In this work, the use of foldcore sandwich elements for building ventilation is investigated. Lightweight folded structures as an alternative to conventional sandwich core materials with the potential to be used for air or fluid transport have been investigated in aerospace engineering. Their high specific stiffness and strength in combination with multifunctional properties permits a reduction of system mass without sacrificing structural performance. Applied to the context of civil engineering, the embodied energy inherent to complex ventilation system may be reduced by the use of multifunctional, lightweight components. This work proposes an application in ultra-lightweight buildings as wall, ceiling or façde elements with integrated air ducts and large two-dimensional ventilation outlets by perforating the room-facing surface layer of the sandwich. The resulting element combines convective and radiative heating in a novel way by thermally coupling the airflow of the space heater with the room-facing surface. The mentioned properties are investigated in theory by forming a 1-dimensional distributed parameter fluid-dynamical model resulting in a boundary value problem. This is extended by a formulation of the heat transfer between fluid and surface layer. The models are evaluated and their parameters identified in practice by analyzing a prototype on a test bench. The results are integrated into a building energy performance simulation in Modelica to enable simulative studies of the impact on building occupant comfort.
{"title":"Modelling the Flow and Heat Transfer Characteristics of Perforated Foldcore Sandwich Composites for Application in Room Air Conditioning","authors":"Marius Oei, Y. Klett, Nadine Harder, D. Flemming, O. Sawodny","doi":"10.1109/COASE.2019.8842913","DOIUrl":"https://doi.org/10.1109/COASE.2019.8842913","url":null,"abstract":"In this work, the use of foldcore sandwich elements for building ventilation is investigated. Lightweight folded structures as an alternative to conventional sandwich core materials with the potential to be used for air or fluid transport have been investigated in aerospace engineering. Their high specific stiffness and strength in combination with multifunctional properties permits a reduction of system mass without sacrificing structural performance. Applied to the context of civil engineering, the embodied energy inherent to complex ventilation system may be reduced by the use of multifunctional, lightweight components. This work proposes an application in ultra-lightweight buildings as wall, ceiling or façde elements with integrated air ducts and large two-dimensional ventilation outlets by perforating the room-facing surface layer of the sandwich. The resulting element combines convective and radiative heating in a novel way by thermally coupling the airflow of the space heater with the room-facing surface. The mentioned properties are investigated in theory by forming a 1-dimensional distributed parameter fluid-dynamical model resulting in a boundary value problem. This is extended by a formulation of the heat transfer between fluid and surface layer. The models are evaluated and their parameters identified in practice by analyzing a prototype on a test bench. The results are integrated into a building energy performance simulation in Modelica to enable simulative studies of the impact on building occupant comfort.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"10 1","pages":"1269-1274"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88202769","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 : 2019-08-01DOI: 10.1109/COASE.2019.8842989
Yuqian Lu, Huiyue Huang, Chao Liu, X. Xu
Manufacturing is becoming smart with capabilities of self-awareness, autonomous decision-making, and adaptive excitation and collaboration. Standardization is a crucial enabler for achieving the required intelligence for smart manufacturing. Though a large number of efforts have been made to the development of manufacturing standards, there is still a significant research gap to be fulfilled. This paper reviews the landscape of existing standards in the context of smart manufacturing and offers guidance on the selection of the standards for different smart manufacturing applications.
{"title":"Standards for Smart Manufacturing: A review","authors":"Yuqian Lu, Huiyue Huang, Chao Liu, X. Xu","doi":"10.1109/COASE.2019.8842989","DOIUrl":"https://doi.org/10.1109/COASE.2019.8842989","url":null,"abstract":"Manufacturing is becoming smart with capabilities of self-awareness, autonomous decision-making, and adaptive excitation and collaboration. Standardization is a crucial enabler for achieving the required intelligence for smart manufacturing. Though a large number of efforts have been made to the development of manufacturing standards, there is still a significant research gap to be fulfilled. This paper reviews the landscape of existing standards in the context of smart manufacturing and offers guidance on the selection of the standards for different smart manufacturing applications.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"33 1","pages":"73-78"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87007512","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 : 2019-08-01DOI: 10.1109/COASE.2019.8843300
H. Wind, Anton Renner, O. Sawodny
Assistance functions are applied in many areas. For material handling excavators, these functions have not been introduced yet. In this paper, an optimization based trajectory generation which minimizes the travel time of a taught trajectory is presented. This playback optimization considers actuator constraints such as velocity, acceleration, jerk and maximum flow rate of the hydraulic pump. A position and velocity controller is designed based on a simplified dynamic model of the actuator in a two-degree-of-freedom control structure. Experimental results on a material handling excavator are presented. The results show the ability of the playback optimization to generate a time-optimal trajectory, considering the given constraints, and the controller to track the reference values.
{"title":"Time-Optimal Playback Trajectory Generation for Hydraulic Material Handling Excavator","authors":"H. Wind, Anton Renner, O. Sawodny","doi":"10.1109/COASE.2019.8843300","DOIUrl":"https://doi.org/10.1109/COASE.2019.8843300","url":null,"abstract":"Assistance functions are applied in many areas. For material handling excavators, these functions have not been introduced yet. In this paper, an optimization based trajectory generation which minimizes the travel time of a taught trajectory is presented. This playback optimization considers actuator constraints such as velocity, acceleration, jerk and maximum flow rate of the hydraulic pump. A position and velocity controller is designed based on a simplified dynamic model of the actuator in a two-degree-of-freedom control structure. Experimental results on a material handling excavator are presented. The results show the ability of the playback optimization to generate a time-optimal trajectory, considering the given constraints, and the controller to track the reference values.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"509 1","pages":"1315-1320"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86846687","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 : 2019-08-01DOI: 10.1109/COASE.2019.8843001
Chuqiao Xu, Xin Liu, Junliang Wang, Jie Zhang, Jin Cao, W. Qin
The long duration of refrigeration compressor performance tests is a key factor restricting the quality testing efficiency and the delivery times. To reduce the time of quality tests in the refrigeration compressor manufacturing systems, data-driven technology is used for forecasting the compressor performance using unsteady-state data in early test phase. The typical methods usually encapsulate two distinct blocks: input range selection and performance prediction. Such fixed and hand-crafted input range, which is crucial for the prediction accuracy and test time saving, may be a sub-optimal choice for diverse varieties of the compressors and prevent their usage for real-time applications. In this paper, we proposed a compressor performance forecasting approach using GA-KRR (genetic algorithm - kernel ridge regression algorithm) nested learning that has a heuristic design to automatically hunt the best input range and a nested learning design to fuse the automatic input range selection and performance prediction into a single learning body. The experimental results on real-world data show the outstanding performance of proposed approach compared with relative approaches, which indicates the test time can be reduced 75%.
{"title":"An Improved GA-KRR Nested Learning Approach for Refrigeration Compressor Performance Forecasting*","authors":"Chuqiao Xu, Xin Liu, Junliang Wang, Jie Zhang, Jin Cao, W. Qin","doi":"10.1109/COASE.2019.8843001","DOIUrl":"https://doi.org/10.1109/COASE.2019.8843001","url":null,"abstract":"The long duration of refrigeration compressor performance tests is a key factor restricting the quality testing efficiency and the delivery times. To reduce the time of quality tests in the refrigeration compressor manufacturing systems, data-driven technology is used for forecasting the compressor performance using unsteady-state data in early test phase. The typical methods usually encapsulate two distinct blocks: input range selection and performance prediction. Such fixed and hand-crafted input range, which is crucial for the prediction accuracy and test time saving, may be a sub-optimal choice for diverse varieties of the compressors and prevent their usage for real-time applications. In this paper, we proposed a compressor performance forecasting approach using GA-KRR (genetic algorithm - kernel ridge regression algorithm) nested learning that has a heuristic design to automatically hunt the best input range and a nested learning design to fuse the automatic input range selection and performance prediction into a single learning body. The experimental results on real-world data show the outstanding performance of proposed approach compared with relative approaches, which indicates the test time can be reduced 75%.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"3 1","pages":"622-627"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87167949","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 : 2019-08-01DOI: 10.1109/COASE.2019.8842963
J. Crowley, Yegeta Zeleke, Berk Altm, R. Sanfelice
We propose a set-based predictive control frame-work to predict inbound dynamic obstacles and optimize trajectories in the interest of safely guiding a vehicle towards a target. To account for uncertainties, the set-based controller generalizes conventional model predictive control and predicts the set that the state of a dynamical system might belong to. This generalization is used to formulate collision avoidance as a hard constraint in the set-based predictive control algorithm. As a proof-of-concept, the proposed framework is applied to a ground vehicle attempting to reach a target while anticipating and evading collisions with obstacles in the operating environment. Other applications of the controller and the associated optimal control problem are discussed.
{"title":"Set-Based Predictive Control for Collision Detection and Evasion","authors":"J. Crowley, Yegeta Zeleke, Berk Altm, R. Sanfelice","doi":"10.1109/COASE.2019.8842963","DOIUrl":"https://doi.org/10.1109/COASE.2019.8842963","url":null,"abstract":"We propose a set-based predictive control frame-work to predict inbound dynamic obstacles and optimize trajectories in the interest of safely guiding a vehicle towards a target. To account for uncertainties, the set-based controller generalizes conventional model predictive control and predicts the set that the state of a dynamical system might belong to. This generalization is used to formulate collision avoidance as a hard constraint in the set-based predictive control algorithm. As a proof-of-concept, the proposed framework is applied to a ground vehicle attempting to reach a target while anticipating and evading collisions with obstacles in the operating environment. Other applications of the controller and the associated optimal control problem are discussed.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"48 1","pages":"541-546"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85572414","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 : 2019-08-01DOI: 10.1109/COASE.2019.8843082
Giovanni Lugaresi, Gianluca Aglio, Federico Folgheraiter, A. Matta
Recently, the connection between manufacturing systems and their digital counterparts has become of great significance for planning and control activities in a short-term scope. However, the alignment of a digital model with a very dynamic system is not always guaranteed, and traditional validation techniques cannot be used since they are designed for off-line simulators and rely on the availability of a large amount of data. This work develops a novel validation procedure inspired by signal-processing theory and a novel approach called quasi Trace Driven Simulation. The procedure is coherent with a Real-Time Simulation framework since it does not require large datasets to provide a good solution. The approach has been tried on test cases which demonstrated its applicability to a manufacturing environment.
{"title":"Real-time Validation of Digital Models for Manufacturing Systems: a Novel Signal-processing-based Approach","authors":"Giovanni Lugaresi, Gianluca Aglio, Federico Folgheraiter, A. Matta","doi":"10.1109/COASE.2019.8843082","DOIUrl":"https://doi.org/10.1109/COASE.2019.8843082","url":null,"abstract":"Recently, the connection between manufacturing systems and their digital counterparts has become of great significance for planning and control activities in a short-term scope. However, the alignment of a digital model with a very dynamic system is not always guaranteed, and traditional validation techniques cannot be used since they are designed for off-line simulators and rely on the availability of a large amount of data. This work develops a novel validation procedure inspired by signal-processing theory and a novel approach called quasi Trace Driven Simulation. The procedure is coherent with a Real-Time Simulation framework since it does not require large datasets to provide a good solution. The approach has been tried on test cases which demonstrated its applicability to a manufacturing environment.","PeriodicalId":6695,"journal":{"name":"2019 IEEE 15th International Conference on Automation Science and Engineering (CASE)","volume":"488 1","pages":"450-455"},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85585200","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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