Pub Date : 2010-06-24DOI: 10.1109/RAAD.2010.5524575
Cristian Axenie, D. Cernega
Current real-time applications should timely deliver synchronized data-sets, minimize latency in their response and meet their performance specifications in the presence of disturbances and faults. The adaptive features of the designed controller are present at the lower control level using specific artificial intelligence techniques. Fuzzy inference system design is the fundamental element to generate an adaptive nonlinear controller for the robot operation in the presence of disturbances and modeling inaccuracies. This paper introduces an adaptive real-time distributed control application with fault tolerance capabilities for differential wheeled mobile robots, named ARTEMIC. Specific design, development and implementation details will be provided in this paper.
{"title":"Adaptive sliding mode controller design for mobile robot fault tolerant control. introducing ARTEMIC.","authors":"Cristian Axenie, D. Cernega","doi":"10.1109/RAAD.2010.5524575","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524575","url":null,"abstract":"Current real-time applications should timely deliver synchronized data-sets, minimize latency in their response and meet their performance specifications in the presence of disturbances and faults. The adaptive features of the designed controller are present at the lower control level using specific artificial intelligence techniques. Fuzzy inference system design is the fundamental element to generate an adaptive nonlinear controller for the robot operation in the presence of disturbances and modeling inaccuracies. This paper introduces an adaptive real-time distributed control application with fault tolerance capabilities for differential wheeled mobile robots, named ARTEMIC. Specific design, development and implementation details will be provided in this paper.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114556912","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524585
A. Ambu, A. Manuello Bertetto, C. Falchi
In this paper two particular subsystems of a worker rover, developed as a collaboration between two academic institutions, has been described for an optimal functionality. The rover has a gripper mechanism and four legs: these components are the on board mechanical subsystems. The gripper mechanism, described in the paper, is designed to operate without motors and the leg of this rover comprises a mechanism for lifting weights and has a decoupling structural joint. The design optimization was performed by means of parametric modelling and numerical simulations.
{"title":"A working lunar rover: Passive gripper mechanism and actuated leg","authors":"A. Ambu, A. Manuello Bertetto, C. Falchi","doi":"10.1109/RAAD.2010.5524585","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524585","url":null,"abstract":"In this paper two particular subsystems of a worker rover, developed as a collaboration between two academic institutions, has been described for an optimal functionality. The rover has a gripper mechanism and four legs: these components are the on board mechanical subsystems. The gripper mechanism, described in the paper, is designed to operate without motors and the leg of this rover comprises a mechanism for lifting weights and has a decoupling structural joint. The design optimization was performed by means of parametric modelling and numerical simulations.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115908908","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524557
Mario Richtsfeld, Robert Schwarz, M. Vincze
This paper presents a system with a fixed robot arm and a scanning unit on a table, which is able to detect and grasp given cylindrical objects with cluttered adjacent objects in soft real-time. In the fields of industrial and home robotics, the requirements of complete 3D data, noiselessness, and obstacle-free situations are often not provided. The contribution of this work is a fast and robust method optimised for fitting cylinders in sparse and noisy range data under difficult and changing light conditions recorded from a single view. The improvements focus on the treatment of different objects on the table. The system must distinguish between them, detect, and grasp the given cylindrical object.
{"title":"Detection of cylindrical objects in tabletop scenes","authors":"Mario Richtsfeld, Robert Schwarz, M. Vincze","doi":"10.1109/RAAD.2010.5524557","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524557","url":null,"abstract":"This paper presents a system with a fixed robot arm and a scanning unit on a table, which is able to detect and grasp given cylindrical objects with cluttered adjacent objects in soft real-time. In the fields of industrial and home robotics, the requirements of complete 3D data, noiselessness, and obstacle-free situations are often not provided. The contribution of this work is a fast and robust method optimised for fitting cylinders in sparse and noisy range data under difficult and changing light conditions recorded from a single view. The improvements focus on the treatment of different objects on the table. The system must distinguish between them, detect, and grasp the given cylindrical object.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122728259","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524537
J. Gáti, G. Kártyás
Internet based teaching and learning systems are ready for the connection with engineering systems at companies and teaching purposed laboratories. In order to make this connection possible, organized descriptions and functionalities are being developed for computer based course programs in engineering. This paper discusses several selected issues from this area. After an introduction about the cited previous work, classroom elements and engineering system resources are discussed and related. Following this, a possible integration with robotic system is explained. Next, course modeling is outlined from the point of view of teachers and students and relationships and processes are discussed as selected issues for practice. Finally, an application of modification by features at the construction of model for teaching program is shown.
{"title":"Virtual classrooms for robotics and other engineering applications","authors":"J. Gáti, G. Kártyás","doi":"10.1109/RAAD.2010.5524537","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524537","url":null,"abstract":"Internet based teaching and learning systems are ready for the connection with engineering systems at companies and teaching purposed laboratories. In order to make this connection possible, organized descriptions and functionalities are being developed for computer based course programs in engineering. This paper discusses several selected issues from this area. After an introduction about the cited previous work, classroom elements and engineering system resources are discussed and related. Following this, a possible integration with robotic system is explained. Next, course modeling is outlined from the point of view of teachers and students and relationships and processes are discussed as selected issues for practice. Finally, an application of modification by features at the construction of model for teaching program is shown.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121028136","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524549
H. Franc, R. Šafarič
This paper describes an application of a fuzzy logic [1] implementation on an ARM-Cortex microcontroller. The microcontroller with integrated fuzzy logic was tested on motor position and speed control application. Fuzzy logic is a subtype of multi-valued logic and can be used in combination with other controller types (PI, PID, neural networks, genetic algorithms, etc.). The microcontroller is the core, or the “brains”, of the device. Complex devices include two or more microcontrollers that exchange data via various communication protocols. Each microcontroller has integrated software, which represents the “mind” of the microcontroller. Without software, the microcontroller is just a useless electronic component. The software represents fuzzy logic, which controls the motor position in this application. The microcontroller's software is often written in the C programming language. Expression often means that there are available more programming languages. Position control has a closed loop, meaning that the position of the motor is regulated to a reference position if the motor load is changing. The first goal of this application is to write a C language source code for a fuzzy logic inference engine for the ARM Cortex M3 microcontroller. The second goal is to test this fuzzy logic inference engine on an automatic door for position control with combination of PI speed controller. The last goal is to analyze the automatic door behavior with fuzzy logic controller by variable door wing weight.
{"title":"ARM-Cortex microcontroller fuzzy position control on an automatic door test-bed","authors":"H. Franc, R. Šafarič","doi":"10.1109/RAAD.2010.5524549","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524549","url":null,"abstract":"This paper describes an application of a fuzzy logic [1] implementation on an ARM-Cortex microcontroller. The microcontroller with integrated fuzzy logic was tested on motor position and speed control application. Fuzzy logic is a subtype of multi-valued logic and can be used in combination with other controller types (PI, PID, neural networks, genetic algorithms, etc.). The microcontroller is the core, or the “brains”, of the device. Complex devices include two or more microcontrollers that exchange data via various communication protocols. Each microcontroller has integrated software, which represents the “mind” of the microcontroller. Without software, the microcontroller is just a useless electronic component. The software represents fuzzy logic, which controls the motor position in this application. The microcontroller's software is often written in the C programming language. Expression often means that there are available more programming languages. Position control has a closed loop, meaning that the position of the motor is regulated to a reference position if the motor load is changing. The first goal of this application is to write a C language source code for a fuzzy logic inference engine for the ARM Cortex M3 microcontroller. The second goal is to test this fuzzy logic inference engine on an automatic door for position control with combination of PI speed controller. The last goal is to analyze the automatic door behavior with fuzzy logic controller by variable door wing weight.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117044533","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524580
J. Sitar, T. Hulmik, V. Racek
Snake robots were realized in purpose of imitating of the snakes and worms movement. This purpose was achieved by applicable kinematic structure and segment design. After that the simulation and verification of designed structure was made with focus on the robot movement possibilities and dimensions. Advantage of introduced robot type is its simplicity and reliability of mechanism, which makes snake movement opposite robots, which are based on complex construction of wheel or track movement. In the presented structure various movement types are coupled into one snaking system. Designed system is verified by simulation and laboratory model of the snake robot segment.
{"title":"Combined snake robot: Analysis and verification of designed structure","authors":"J. Sitar, T. Hulmik, V. Racek","doi":"10.1109/RAAD.2010.5524580","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524580","url":null,"abstract":"Snake robots were realized in purpose of imitating of the snakes and worms movement. This purpose was achieved by applicable kinematic structure and segment design. After that the simulation and verification of designed structure was made with focus on the robot movement possibilities and dimensions. Advantage of introduced robot type is its simplicity and reliability of mechanism, which makes snake movement opposite robots, which are based on complex construction of wheel or track movement. In the presented structure various movement types are coupled into one snaking system. Designed system is verified by simulation and laboratory model of the snake robot segment.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121469222","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524547
A. Dobra, N. Joni
One can observe an enormous progress in robotic arc welding during the last two decades. However, the existing means for monitoring and the OLP systems based on these achievements still do not provide adequate welding operations planning. The programming of robotic systems for arc welding is still a time-consuming process, which requires substantial expertise in both robotics and the arc welding process. The shortcomings relate mainly to weld sequencing and positioner motion planning. The paper is aiming to establish a technical / theoretical basis for the positioner motion planning, beginning with the simplest case, that of quasi one-dimensional oversized parts.
{"title":"Robotized welding of large one-dimensional structures","authors":"A. Dobra, N. Joni","doi":"10.1109/RAAD.2010.5524547","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524547","url":null,"abstract":"One can observe an enormous progress in robotic arc welding during the last two decades. However, the existing means for monitoring and the OLP systems based on these achievements still do not provide adequate welding operations planning. The programming of robotic systems for arc welding is still a time-consuming process, which requires substantial expertise in both robotics and the arc welding process. The shortcomings relate mainly to weld sequencing and positioner motion planning. The paper is aiming to establish a technical / theoretical basis for the positioner motion planning, beginning with the simplest case, that of quasi one-dimensional oversized parts.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"241 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126470391","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524596
J. Cinkelj, J. Cinkelj, R. Kamnik, Peter Cepon, Peter Čepon, M. Mihelj, M. Mihelj, M. Munih
Automation is supposed to improve working conditions and safety in construction industry, as it already did in manufacturing industries. This paper presents the development of a robotic control system for a commercially available hydraulic telescopic handler. The target application for the telescopic handler is semi-automated assembly of facade panels. The base handler was upgraded with two additional hydraulic axes, position sensors and closed-loop control system, while the original handler safety assurance mechanisms were preserved. The control approach is based on a PI controller with velocity feedforward and valve overlap compensation. The direct and inverse kinematic models of handler mechanism were developed to enable control of end-effector motion along a straight line in Cartesian coordinate system. The motion performances were evaluated following the ISO 9283 standard with payload of 2000 kg. Results show the repeatability of positioning bellow 7.0 mm and the straight line tracking error smaller than 63 mm.
{"title":"Robotic control system for hydraulic telescopic handler","authors":"J. Cinkelj, J. Cinkelj, R. Kamnik, Peter Cepon, Peter Čepon, M. Mihelj, M. Mihelj, M. Munih","doi":"10.1109/RAAD.2010.5524596","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524596","url":null,"abstract":"Automation is supposed to improve working conditions and safety in construction industry, as it already did in manufacturing industries. This paper presents the development of a robotic control system for a commercially available hydraulic telescopic handler. The target application for the telescopic handler is semi-automated assembly of facade panels. The base handler was upgraded with two additional hydraulic axes, position sensors and closed-loop control system, while the original handler safety assurance mechanisms were preserved. The control approach is based on a PI controller with velocity feedforward and valve overlap compensation. The direct and inverse kinematic models of handler mechanism were developed to enable control of end-effector motion along a straight line in Cartesian coordinate system. The motion performances were evaluated following the ISO 9283 standard with payload of 2000 kg. Results show the repeatability of positioning bellow 7.0 mm and the straight line tracking error smaller than 63 mm.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126567492","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524551
G. Hermann, M. Báthor, Z. Bánki
The aim of the project, described in this paper, is to retrofit a Zeiss length measuring machine for the calibration of linear scales, with a pitch distance of a few micrometers. The retrofitting consists of optics, equipped with a CCD camera, for capturing the line sizes and distances, an appropriate illumination system, a motion system carrying the scale and providing linear motion at constant speed. The paper starts with discussing the various definitions of the pitch distance. From these definitions simple algorithms, to determine the pitch distance, are derived. The main point is to minimize the effect of non-linearity and diffraction, by using appropriate optics and illumination, hereby improving measurement accuracy. The carriage carrying the scale is driven by ultrasonic piezomotor providing nanometer resolution. The displacement is measured by an HP laser interferometer. For higher resolution the CCD camera system can be replaced by a near field microscope.
{"title":"Calibration machine for linear scales","authors":"G. Hermann, M. Báthor, Z. Bánki","doi":"10.1109/RAAD.2010.5524551","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524551","url":null,"abstract":"The aim of the project, described in this paper, is to retrofit a Zeiss length measuring machine for the calibration of linear scales, with a pitch distance of a few micrometers. The retrofitting consists of optics, equipped with a CCD camera, for capturing the line sizes and distances, an appropriate illumination system, a motion system carrying the scale and providing linear motion at constant speed. The paper starts with discussing the various definitions of the pitch distance. From these definitions simple algorithms, to determine the pitch distance, are derived. The main point is to minimize the effect of non-linearity and diffraction, by using appropriate optics and illumination, hereby improving measurement accuracy. The carriage carrying the scale is driven by ultrasonic piezomotor providing nanometer resolution. The displacement is measured by an HP laser interferometer. For higher resolution the CCD camera system can be replaced by a near field microscope.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115765553","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524613
J. Tar, I. Rudas, J. Bitó, K. Kozlowski, C. Pozna
The “Model Reference Adaptive Control (MRAC)” is a popular approach from the early nineties to our days. Its basic idea is the application of proper feedback that makes the behavior of the controlled system identical to that of the “reference model” that normally is simple enough to control. The idea has many particular variants with the common feature that they are designed by the use of Lyapunov's 2nd (“direct”) method that normally applies a quadratic Lyapunov function constructed of the tracking error and further additional terms. Though this approach normally guarantees global asymptotic stability, its use can entail complicated tuning that may have disadvantages whenever very fast applications are needed. In this paper an alternative problem tackling, the application of “Robust Fixed Point Transformations (RFPT)” in the MRAC technique is recommended. This approach applies strongly saturated, multiplicative nonlinear terms causing a kind of “deformation” of the input of the available imprecise system model. Instead parameter tuning that is typical in the traditional MRAC it operates with a simple convergence guaranteed only within a local basin of attraction. This technique can well compensate the simultaneous consequences of modeling errors and external disturbances that normally can “fob” the more traditional, tuning based approaches. As a potential application paradigm the novel MRAC control of a “cart - beam - hamper” system is considered. The conclusions of the paper are illustrated by simulation results.
{"title":"A novel approach to the Model Reference Adaptive Control of MIMO systems","authors":"J. Tar, I. Rudas, J. Bitó, K. Kozlowski, C. Pozna","doi":"10.1109/RAAD.2010.5524613","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524613","url":null,"abstract":"The “Model Reference Adaptive Control (MRAC)” is a popular approach from the early nineties to our days. Its basic idea is the application of proper feedback that makes the behavior of the controlled system identical to that of the “reference model” that normally is simple enough to control. The idea has many particular variants with the common feature that they are designed by the use of Lyapunov's 2nd (“direct”) method that normally applies a quadratic Lyapunov function constructed of the tracking error and further additional terms. Though this approach normally guarantees global asymptotic stability, its use can entail complicated tuning that may have disadvantages whenever very fast applications are needed. In this paper an alternative problem tackling, the application of “Robust Fixed Point Transformations (RFPT)” in the MRAC technique is recommended. This approach applies strongly saturated, multiplicative nonlinear terms causing a kind of “deformation” of the input of the available imprecise system model. Instead parameter tuning that is typical in the traditional MRAC it operates with a simple convergence guaranteed only within a local basin of attraction. This technique can well compensate the simultaneous consequences of modeling errors and external disturbances that normally can “fob” the more traditional, tuning based approaches. As a potential application paradigm the novel MRAC control of a “cart - beam - hamper” system is considered. The conclusions of the paper are illustrated by simulation results.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115489552","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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