Pub Date : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472968
Yikun Xiong, M. von Essen, J. Hirvonen, P. Kallio
Calibration is of great significance in the development of automatic micromanipulation systems. This paper presents a novel vision based procedure for three dimensional (3D) calibration of micromanipulators. Two major issues in the proposed calibration approach - vision system calibration and manipulator kinematic calibration - are discussed in details in this paper. Verification and evaluation experiments are conducted using a 3D micromanipulator in a microrobotic fiber characterization platform. The results demonstrate that the proposed calibration approach is able to reduce the pose error below 5 micrometers.
{"title":"Vision based 3D calibration of micromanipulator in microrobotic fiber characterization platform","authors":"Yikun Xiong, M. von Essen, J. Hirvonen, P. Kallio","doi":"10.1109/3M-NANO.2012.6472968","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472968","url":null,"abstract":"Calibration is of great significance in the development of automatic micromanipulation systems. This paper presents a novel vision based procedure for three dimensional (3D) calibration of micromanipulators. Two major issues in the proposed calibration approach - vision system calibration and manipulator kinematic calibration - are discussed in details in this paper. Verification and evaluation experiments are conducted using a 3D micromanipulator in a microrobotic fiber characterization platform. The results demonstrate that the proposed calibration approach is able to reduce the pose error below 5 micrometers.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128956299","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472985
Fan Chenyang, Li Xiaojie, W. Falin
Aiming at the condition that when the Fuze MEMS (micro electro mechanical system) S&A system bears setback/centrifugal overload in an experiment, the clamping head of a setback/centrifugal slide block deforms considerably when entering the clamping seat of a base plate, so that the slide block cannot be locked successfully by the clamping seat of the base plate, this paper presents an MEMS slide block locking mechanism with an elastic supporting structure. The structure of the mechanism, which is contrary to the original structure, is that rigid barbs are arranged on the clamping head, and an elastic supporting arm is arranged on the base plate. The finite element simulation with ANSYS shows that when the clamping head and the clamping arm of the locking mechanism with the elastic supporting structure bear overload, the stress of the dangerous cross-section of the locking mechanism is reduced by 52%, compared with that of the original mechanism, so that plastic deformation is avoided, and the slide block can enter the clamping seat smoothly and locked. Therefore, it can provide selection and reference for the design of locking mechanisms of MEMS S&A system in future.
{"title":"MEMS slide block locking mechanism based on elastic supporting structure","authors":"Fan Chenyang, Li Xiaojie, W. Falin","doi":"10.1109/3M-NANO.2012.6472985","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472985","url":null,"abstract":"Aiming at the condition that when the Fuze MEMS (micro electro mechanical system) S&A system bears setback/centrifugal overload in an experiment, the clamping head of a setback/centrifugal slide block deforms considerably when entering the clamping seat of a base plate, so that the slide block cannot be locked successfully by the clamping seat of the base plate, this paper presents an MEMS slide block locking mechanism with an elastic supporting structure. The structure of the mechanism, which is contrary to the original structure, is that rigid barbs are arranged on the clamping head, and an elastic supporting arm is arranged on the base plate. The finite element simulation with ANSYS shows that when the clamping head and the clamping arm of the locking mechanism with the elastic supporting structure bear overload, the stress of the dangerous cross-section of the locking mechanism is reduced by 52%, compared with that of the original mechanism, so that plastic deformation is avoided, and the slide block can enter the clamping seat smoothly and locked. Therefore, it can provide selection and reference for the design of locking mechanisms of MEMS S&A system in future.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125904387","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472958
Weijie Sun, J. Yeow, Zhendong Sun
In this paper, we will study the output-error-constrained tracking control problem of an electrostatic torsional micromirror beyond the pull-in limit. We will first show that this problem can be formulated as a robust output regulation problem and it further boils down to a robust regulation problem with output-constrained by adaptive internal model design, the solution of which would in turn lead to the solution of the original problem. Then we design a regulation controller for such a regulation problem by using the barrier Lyapunov function technique. Our adaptive control law ensures the electrostatic torsional micromirror with a enhanced tracking performance in the sense that the moveable micromirror can achieve the sinusoidal wave scanning of any frequency up to a full gap operation without contacts of the fixed bottom electrode, and furthermore, the estimated sinusoidal wave frequency converges to its real value.
{"title":"Tracking control of an electrostatic torsional micromirror beyond the pull-in limit with enhanced performance","authors":"Weijie Sun, J. Yeow, Zhendong Sun","doi":"10.1109/3M-NANO.2012.6472958","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472958","url":null,"abstract":"In this paper, we will study the output-error-constrained tracking control problem of an electrostatic torsional micromirror beyond the pull-in limit. We will first show that this problem can be formulated as a robust output regulation problem and it further boils down to a robust regulation problem with output-constrained by adaptive internal model design, the solution of which would in turn lead to the solution of the original problem. Then we design a regulation controller for such a regulation problem by using the barrier Lyapunov function technique. Our adaptive control law ensures the electrostatic torsional micromirror with a enhanced tracking performance in the sense that the moveable micromirror can achieve the sinusoidal wave scanning of any frequency up to a full gap operation without contacts of the fixed bottom electrode, and furthermore, the estimated sinusoidal wave frequency converges to its real value.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114284304","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472965
Yankun Liu, W. Lou, Qingfang Shi, Mingru Guo, Peng Liu
With the development of nanotechnology and Micro-Electro-Mechanical System (MEMS) technology, micro-pores films are widely applied in the fabrication of important components of nano-devices and MEMS. It is found that micro-pores films have the effect on the separation of the two-phases and the fix of the phase interfaces, due to huge network structures and highly ordered distribution of pore structure. Based on the combined effects of the inertial impaction, the interception and the diffusion, PTFE membrane filter is adopted. Furthermore, we perform the simulation by the COMSOL Multiphysics, which reflects the filtering effect of the PTFE nano-film materials. Finally we study the simulation of the protective micro-particles in PTFE membrane materials.
{"title":"Finite element simulation of PTFE nano-film two-phase filter","authors":"Yankun Liu, W. Lou, Qingfang Shi, Mingru Guo, Peng Liu","doi":"10.1109/3M-NANO.2012.6472965","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472965","url":null,"abstract":"With the development of nanotechnology and Micro-Electro-Mechanical System (MEMS) technology, micro-pores films are widely applied in the fabrication of important components of nano-devices and MEMS. It is found that micro-pores films have the effect on the separation of the two-phases and the fix of the phase interfaces, due to huge network structures and highly ordered distribution of pore structure. Based on the combined effects of the inertial impaction, the interception and the diffusion, PTFE membrane filter is adopted. Furthermore, we perform the simulation by the COMSOL Multiphysics, which reflects the filtering effect of the PTFE nano-film materials. Finally we study the simulation of the protective micro-particles in PTFE membrane materials.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122672601","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472972
C. Li, Min Yeop Kim, T. Ko, Jong Kweon Park
Conventionally, tool wear is very high or fracture when processing high hardness steel by milling method. So, we attempted to design a fixture apparatus for hybrid machining process (HMP) by ultrasonic vibration using finite element method. Now this fixture apparatus has been manufactured. We can do many types of hybrid machining experiments using this fixture. And then the milling machining was conducted to compare the effects of the ultrasonic vibration. The results showed that the tool wear and surface roughness with ultrasonic vibration was smoother than without the fixture vibration. This result could be explained as accelerating the heat transfer by ultrasonic vibration.
{"title":"The effects of ultrasonic vibration on surface finish and tool wear in end-milling machining","authors":"C. Li, Min Yeop Kim, T. Ko, Jong Kweon Park","doi":"10.1109/3M-NANO.2012.6472972","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472972","url":null,"abstract":"Conventionally, tool wear is very high or fracture when processing high hardness steel by milling method. So, we attempted to design a fixture apparatus for hybrid machining process (HMP) by ultrasonic vibration using finite element method. Now this fixture apparatus has been manufactured. We can do many types of hybrid machining experiments using this fixture. And then the milling machining was conducted to compare the effects of the ultrasonic vibration. The results showed that the tool wear and surface roughness with ultrasonic vibration was smoother than without the fixture vibration. This result could be explained as accelerating the heat transfer by ultrasonic vibration.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"380 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122170249","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472997
H. Tao, X. Tan, Lingtian Diao, Xiao-wei Song, Z. Hao, Jingquan Lin, Bin Chen
Micro- and nanoscale structures on a material surface formed by femotosecond laser processing have greatly changed its optical characteristics. In this work, the coloring of Al surface has been realized with scanning focused femtosecond laser beam on the Al surface. We further apply femtosecond laser filamentation to form micro- and nano-structures on a spherical Al surface, resulting in a black appearance of the spherical Al. This work opens ways to fabricate strong light-trapping micro- and nano-structure on a non-planar surface without the complexity of a 4-axis sample control.
{"title":"Extending femtosecond laser fabrication of micro- and nanoscale structures from a planar to non-planar metal surface","authors":"H. Tao, X. Tan, Lingtian Diao, Xiao-wei Song, Z. Hao, Jingquan Lin, Bin Chen","doi":"10.1109/3M-NANO.2012.6472997","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472997","url":null,"abstract":"Micro- and nanoscale structures on a material surface formed by femotosecond laser processing have greatly changed its optical characteristics. In this work, the coloring of Al surface has been realized with scanning focused femtosecond laser beam on the Al surface. We further apply femtosecond laser filamentation to form micro- and nano-structures on a spherical Al surface, resulting in a black appearance of the spherical Al. This work opens ways to fabricate strong light-trapping micro- and nano-structure on a non-planar surface without the complexity of a 4-axis sample control.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124107498","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472936
Yanding Qin, Yanling Tian, Dawei Zhang, Weiguo Gao, B. Shirinzadeh, U. Bhagat, L. Clark
A decoupled piezo-driven compliant mechanism has been designed and manufactured to track 2-DOF trajectories. Although it features decoupled characteristics, the small cross axis coupling can result in poor tracking performance in 2-DOF trajectories. For such structures, the damping ratio is so small that the modal vibrations are likely to be excited, which greatly degrade its positioning accuracy. In this paper, an H∞ controller is designed to make the closed-loop system match a well-damped second order system. The H∞ controller effectively suppresses the modal vibrations and further reduces the cross axis coupling motions. Experimental results show that the mechanism's tracking performance in 2-DOF trajectories is significantly improved.
{"title":"Motion control of a 2-DOF decoupled compliant mechanism using H∞ synthesis","authors":"Yanding Qin, Yanling Tian, Dawei Zhang, Weiguo Gao, B. Shirinzadeh, U. Bhagat, L. Clark","doi":"10.1109/3M-NANO.2012.6472936","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472936","url":null,"abstract":"A decoupled piezo-driven compliant mechanism has been designed and manufactured to track 2-DOF trajectories. Although it features decoupled characteristics, the small cross axis coupling can result in poor tracking performance in 2-DOF trajectories. For such structures, the damping ratio is so small that the modal vibrations are likely to be excited, which greatly degrade its positioning accuracy. In this paper, an H∞ controller is designed to make the closed-loop system match a well-damped second order system. The H∞ controller effectively suppresses the modal vibrations and further reduces the cross axis coupling motions. Experimental results show that the mechanism's tracking performance in 2-DOF trajectories is significantly improved.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117120403","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472970
Y. Shu, L. Qi, Zhen-Feng Sun, Hejun Li
A molecular structural mechanics model, based on a link between molecular and solid mechanics, was built to evaluate mechanical properties of graphene nanoribbons (GNRs). This model can describe the true state of GNRs more realistically comparing to other simulation methods because of considering the structure and properties of the carbon-carbon bonds. GNRs with different edge types, such as armchair and zigzag types, were simulated under a uniaxial load by using the proposed model. The Young's moduli of GNRs were obtained. Then the influence of edge type and size of GNRs on Young's modulus was also investigated. The results show that GNRs have a similar Young's modulus to carbon nanotubes, which is in good agreement with the previous studies, indicating that the proposed molecular structural mechanics model can be used to predicate the mechanical properties of GNRs.
{"title":"Numerical investigation of size and chirality effects on mechanical properties of graphene nanoribbons","authors":"Y. Shu, L. Qi, Zhen-Feng Sun, Hejun Li","doi":"10.1109/3M-NANO.2012.6472970","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472970","url":null,"abstract":"A molecular structural mechanics model, based on a link between molecular and solid mechanics, was built to evaluate mechanical properties of graphene nanoribbons (GNRs). This model can describe the true state of GNRs more realistically comparing to other simulation methods because of considering the structure and properties of the carbon-carbon bonds. GNRs with different edge types, such as armchair and zigzag types, were simulated under a uniaxial load by using the proposed model. The Young's moduli of GNRs were obtained. Then the influence of edge type and size of GNRs on Young's modulus was also investigated. The results show that GNRs have a similar Young's modulus to carbon nanotubes, which is in good agreement with the previous studies, indicating that the proposed molecular structural mechanics model can be used to predicate the mechanical properties of GNRs.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114488867","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472987
Zou Jinlong, Li Xiaojie, Lei Yaru
Based on the reading and the analyzing of relative literatures, this paper introduced basic concepts and fabrication processes of two in situ charge technologies - porous silicon energetic material and converting porous metal to primary explosive based on silicon process, and analyzed the structures and working principles of the micro-donators with two in situ charge technologies. This paper also introduced latest process of explosive train of the MEMS S&A. On these bases, the structure and working principle of silicon MEMS S&A proposed by US army was discussed, and this MEMS S&A is based on in situ charge and suitable for wafer-level mass fabrication. Some views about the development of the silicon MEMS S&A were also put forward.
{"title":"Technology of in situ charge promotes the development of MEMS safety and arming device","authors":"Zou Jinlong, Li Xiaojie, Lei Yaru","doi":"10.1109/3M-NANO.2012.6472987","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472987","url":null,"abstract":"Based on the reading and the analyzing of relative literatures, this paper introduced basic concepts and fabrication processes of two in situ charge technologies - porous silicon energetic material and converting porous metal to primary explosive based on silicon process, and analyzed the structures and working principles of the micro-donators with two in situ charge technologies. This paper also introduced latest process of explosive train of the MEMS S&A. On these bases, the structure and working principle of silicon MEMS S&A proposed by US army was discussed, and this MEMS S&A is based on in situ charge and suitable for wafer-level mass fabrication. Some views about the development of the silicon MEMS S&A were also put forward.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116416362","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 : 2012-08-01DOI: 10.1109/3M-NANO.2012.6472994
Ming-Dao Wu, Cheng-Chun Huang, W. Shih, S. Fatikow
We electrothermally determined the internal electrical resistivity of a single carbon nanocoil (CNC) which was assembled on the AFM tip. A heat-transfer modeling which considered the Joule's heat was employed to extract the electrical resistivity. The current and resistance of the loop circuits were applied in the calculation in which the thermal measurement was not required. During the electrical measurement, the overall resistance of the heating loop depended on the current variation and decreased abruptly at the beginning of the measurement. It was suggested that the contact resistances between the CNC and metal electrodes were eliminated due to the shortened difference of the work functions between the two materials. The developed electrothermal model agreed well with the experiment at steady state and gave the CNC resistivity of 1.64*10-4~8.81*10-4 Ω-m. This result confirmed the amorphous phase of the synthesized CNC.
{"title":"Electrothermal effect on the electrical resistivity of single carbon nanocoils","authors":"Ming-Dao Wu, Cheng-Chun Huang, W. Shih, S. Fatikow","doi":"10.1109/3M-NANO.2012.6472994","DOIUrl":"https://doi.org/10.1109/3M-NANO.2012.6472994","url":null,"abstract":"We electrothermally determined the internal electrical resistivity of a single carbon nanocoil (CNC) which was assembled on the AFM tip. A heat-transfer modeling which considered the Joule's heat was employed to extract the electrical resistivity. The current and resistance of the loop circuits were applied in the calculation in which the thermal measurement was not required. During the electrical measurement, the overall resistance of the heating loop depended on the current variation and decreased abruptly at the beginning of the measurement. It was suggested that the contact resistances between the CNC and metal electrodes were eliminated due to the shortened difference of the work functions between the two materials. The developed electrothermal model agreed well with the experiment at steady state and gave the CNC resistivity of 1.64*10-4~8.81*10-4 Ω-m. This result confirmed the amorphous phase of the synthesized CNC.","PeriodicalId":134364,"journal":{"name":"2012 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121764543","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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