Pub Date : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787535
Sébastien Ferrand, Maxime Rattier, C. Moluçon, Kevin Gautier, Pierrick Cheiney, E. Peter, Marco Mancini
This paper will present the sensor miniaturization strategy for FOG and accelerometers embedded in the UmiX IMU. It will also discuss the performances achieved by the sensors.
{"title":"UmiX series: How to miniaturize FOG technology","authors":"Sébastien Ferrand, Maxime Rattier, C. Moluçon, Kevin Gautier, Pierrick Cheiney, E. Peter, Marco Mancini","doi":"10.1109/INERTIAL53425.2022.9787535","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787535","url":null,"abstract":"This paper will present the sensor miniaturization strategy for FOG and accelerometers embedded in the UmiX IMU. It will also discuss the performances achieved by the sensors.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132417420","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 : 2022-05-08DOI: 10.1109/inertial53425.2022.9787733
{"title":"INERTIAL 2022 Preface","authors":"","doi":"10.1109/inertial53425.2022.9787733","DOIUrl":"https://doi.org/10.1109/inertial53425.2022.9787733","url":null,"abstract":"","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132982875","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}
ONERA is working on a research project to design a SAR sensor prototype suitable for operation on board an UAV. In SAR processing domain a precise knowledge of airborne vehicle’s trajectory is needed. After a first validation campaign, analyses of the trajectories show significant instabilities in the post-processing stage of our inertial data. Distribution of ground GNSS stations was not optimal and may be at the origin of this phenomenon. To quantify errors on trajectory, autofocus techniques have been applied and after this step SAR images presented a better focusing proving efficiency of the motion compensation from autofocus algorithm.
{"title":"SAR Imaging Challenges on UAV Trajectory Restitution Study Case with SAR-Light Prototype at X-Band","authors":"Nouvel Jean-Francois, Castet Nicolas, Henrion Jérôme","doi":"10.1109/INERTIAL53425.2022.9787523","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787523","url":null,"abstract":"ONERA is working on a research project to design a SAR sensor prototype suitable for operation on board an UAV. In SAR processing domain a precise knowledge of airborne vehicle’s trajectory is needed. After a first validation campaign, analyses of the trajectories show significant instabilities in the post-processing stage of our inertial data. Distribution of ground GNSS stations was not optimal and may be at the origin of this phenomenon. To quantify errors on trajectory, autofocus techniques have been applied and after this step SAR images presented a better focusing proving efficiency of the motion compensation from autofocus algorithm.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122232310","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 : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787729
Tongqiao Miao, Yi Xu, Qingsong Li, Jiangkun Sun, Xuezhong Wu, D. Xiao, Xiaoping Hu
This paper reports a self-calibrating method based on the mode reversal to real-time compensation the temperature drift of Honeycomb disk resonator gyroscope (HDRG). Through analyzing the mechanism of the temperature drift and designing the experiment of verification, the temperature drift of HDRG can be effectively suppressed. It is demonstrated that the zero-rate bias (ZRB) of HDRG in turn-on period can reach 0.08 °/h (1σ) with self-calibrating method. Also, the bias stability of 1.85 °/h (1σ) is realized when the temperature is changed from 0 ℃ to 60 ℃ at the heating speed of 1 ℃/min. Interestingly, the phenomenon of nonlinear change of ZRB is observed at under variable temperature, which may be due to the thermal stress of the immature packaging of device or the modal coupling between different modes of MEMS resonator. Finally, the approach in this paper is also widely applicable to other vibration inertial sensors with symmetrical mode shapes, which may be useful for ZRB compensation on inertial sensors with high performance.
{"title":"Temperature Drift Self-calibration for Honeycomb-like Disk Resonator Gyroscope","authors":"Tongqiao Miao, Yi Xu, Qingsong Li, Jiangkun Sun, Xuezhong Wu, D. Xiao, Xiaoping Hu","doi":"10.1109/INERTIAL53425.2022.9787729","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787729","url":null,"abstract":"This paper reports a self-calibrating method based on the mode reversal to real-time compensation the temperature drift of Honeycomb disk resonator gyroscope (HDRG). Through analyzing the mechanism of the temperature drift and designing the experiment of verification, the temperature drift of HDRG can be effectively suppressed. It is demonstrated that the zero-rate bias (ZRB) of HDRG in turn-on period can reach 0.08 °/h (1σ) with self-calibrating method. Also, the bias stability of 1.85 °/h (1σ) is realized when the temperature is changed from 0 ℃ to 60 ℃ at the heating speed of 1 ℃/min. Interestingly, the phenomenon of nonlinear change of ZRB is observed at under variable temperature, which may be due to the thermal stress of the immature packaging of device or the modal coupling between different modes of MEMS resonator. Finally, the approach in this paper is also widely applicable to other vibration inertial sensors with symmetrical mode shapes, which may be useful for ZRB compensation on inertial sensors with high performance.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115431996","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 : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787727
Mehran Hosseini‐Pishrobat, Baha Erim Uzunoglu, Derin Erkan, E. Tatar
Disk resonator gyroscopes (DRGs) utilize the circular symmetry of a set of concentric rings to realize high-performance MEMS gyroscopes. We set forth an analytical method to calculate the mode shapes of the rings and then obtain the corresponding modal mass, Coriolis mass, and stiffness. Following the Ritz method, we minimize the total potential energy of the rings subject to the boundary conditions imposed by the spokes that connect the rings. We show the efficacy of our method using the frequency response of a fabricated DRG and comparison with the finite element method (FEM). With respect to the FEM, our modeling is more straightforward, more intuitive, and can be extended to model imperfections and ensuing effects such as quadrature error and frequency split.
{"title":"An Analtical Model for Vibration Analysis of Disk Resonator Gyroscopes","authors":"Mehran Hosseini‐Pishrobat, Baha Erim Uzunoglu, Derin Erkan, E. Tatar","doi":"10.1109/INERTIAL53425.2022.9787727","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787727","url":null,"abstract":"Disk resonator gyroscopes (DRGs) utilize the circular symmetry of a set of concentric rings to realize high-performance MEMS gyroscopes. We set forth an analytical method to calculate the mode shapes of the rings and then obtain the corresponding modal mass, Coriolis mass, and stiffness. Following the Ritz method, we minimize the total potential energy of the rings subject to the boundary conditions imposed by the spokes that connect the rings. We show the efficacy of our method using the frequency response of a fabricated DRG and comparison with the finite element method (FEM). With respect to the FEM, our modeling is more straightforward, more intuitive, and can be extended to model imperfections and ensuing effects such as quadrature error and frequency split.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121157106","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 : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787719
T. Perrier, O. Traon, R. Lévy, J. Guerard, A. A. Ledier, P. Lavenus
This paper reports a novel axisymmetric quartz MEMS gyroscope, named GYTRIX, able to work -for the first time to our knowledge- as a whole angle gyro. The proposed GYTRIX cell differs from the state of the art by the use of balanced vibration modes, naturally decoupled from the support, and a very simple and pure axisymmetric design, implementing an original principle of decoupling of the useful modes, which gives the resonators very high quality factors. As a proof of concept, the gyroscope presented is designed to operate in open-loop mode in order to facilitate the first characterizations of the cell. Thanks to its symmetry, isotropy and high quality factor, the gyroscope characteristics give up towards a theoretical angular random walk of 0.003°/√h and a bias stability better than 0.1°/h.
{"title":"Gytrix, a novel axisymmetric quartz MEMS gyroscope for navigation purpose","authors":"T. Perrier, O. Traon, R. Lévy, J. Guerard, A. A. Ledier, P. Lavenus","doi":"10.1109/INERTIAL53425.2022.9787719","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787719","url":null,"abstract":"This paper reports a novel axisymmetric quartz MEMS gyroscope, named GYTRIX, able to work -for the first time to our knowledge- as a whole angle gyro. The proposed GYTRIX cell differs from the state of the art by the use of balanced vibration modes, naturally decoupled from the support, and a very simple and pure axisymmetric design, implementing an original principle of decoupling of the useful modes, which gives the resonators very high quality factors. As a proof of concept, the gyroscope presented is designed to operate in open-loop mode in order to facilitate the first characterizations of the cell. Thanks to its symmetry, isotropy and high quality factor, the gyroscope characteristics give up towards a theoretical angular random walk of 0.003°/√h and a bias stability better than 0.1°/h.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"2003 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125786190","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 : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787765
Alexandre Azier, B. Leverrier, N. Kacem, B. Chaumet, N. Bouhaddi
Due to the structure symmetry of the architecture of most of the highly sensitive MEMS gyroscopes, their native quadrature error is null. However, with the actual precision limitations of the silicon etching processes, some dispersion in the etching of the flexure springs may results in non-zero coupling stiffness between the X and Y-axis, which leads to a quadrature error. As the stiffness of the flexure springs highly depends on its width, it is necessary to investigate the impact of the local width dispersions on the stiffness coupling. In this paper we report on our approach, which is based on the use of Finite Element Analysis (FEA) to determine the evolution of the stiffness matrix of the springs of our gyroscope regarding the bending beam width imperfections. Based on our results, a statistical analysis is carried out in order to evaluate the mean and the standard deviation of the absolute value of the amplitude of the quadrature signal for a given beam width variation. Then, we compare our model to the actual quadrature error of our gyroscopes, which has been measured with a dedicated bench. It turns out that a bending beam width variation of 0.9% leads to a quadrature error discrepancy with the same order of magnitude that the one measured, emphasizing the importance of the consideration of the bending beams width variation during the dimensioning of MEMS gyroscopes, in order to avoid high quadrature error.
{"title":"Investigating the effects of Silicon etching imperfections on the quadrature error in MEMS gyroscopes","authors":"Alexandre Azier, B. Leverrier, N. Kacem, B. Chaumet, N. Bouhaddi","doi":"10.1109/INERTIAL53425.2022.9787765","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787765","url":null,"abstract":"Due to the structure symmetry of the architecture of most of the highly sensitive MEMS gyroscopes, their native quadrature error is null. However, with the actual precision limitations of the silicon etching processes, some dispersion in the etching of the flexure springs may results in non-zero coupling stiffness between the X and Y-axis, which leads to a quadrature error. As the stiffness of the flexure springs highly depends on its width, it is necessary to investigate the impact of the local width dispersions on the stiffness coupling. In this paper we report on our approach, which is based on the use of Finite Element Analysis (FEA) to determine the evolution of the stiffness matrix of the springs of our gyroscope regarding the bending beam width imperfections. Based on our results, a statistical analysis is carried out in order to evaluate the mean and the standard deviation of the absolute value of the amplitude of the quadrature signal for a given beam width variation. Then, we compare our model to the actual quadrature error of our gyroscopes, which has been measured with a dedicated bench. It turns out that a bending beam width variation of 0.9% leads to a quadrature error discrepancy with the same order of magnitude that the one measured, emphasizing the importance of the consideration of the bending beams width variation during the dimensioning of MEMS gyroscopes, in order to avoid high quadrature error.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125948221","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 : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787531
A. Nastro, M. Ferrari, V. Ferrari, C. I. Mura, Andrea Labombarda, M. Viti, S. D. Feste
A Data Fusion (DF) approach for noise reduction in a system of multiple MEMS inclinometers is presented. The outputs of four inclinometers (ST IIS2CLX), that are nominally identical and set with the same operative conditions, have been acquired for 48 h consecutively. Each acquired dataset has been studied separately employing the Overlapping Allan VARiance (OAVAR) analysis to identify the Velocity Random Walk (VRW) and the Bias Instability (BI) noise contributions. The DF approach based on ensemble averaging across samples has been then applied combining the four acquired datasets, thus creating new datasets DFn, that contain averaged output data of n inclinometers at each acquisition time. The VRW and BI noise contributions of the DFn datasets have been identified through the OAVAR analysis and compared with the noise contributions of single inclinometers. Experimental results have shown a reduction of the noise variance σ2n for both the BI and VRW with a factor 1/n or, equivalently, the noise deviation σn with a factor $1/sqrt n $, in good agreement with theoretical expectations.
{"title":"Noise Reduction by Data Fusion in a Multisensor System of Replicated MEMS Inclinometers","authors":"A. Nastro, M. Ferrari, V. Ferrari, C. I. Mura, Andrea Labombarda, M. Viti, S. D. Feste","doi":"10.1109/INERTIAL53425.2022.9787531","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787531","url":null,"abstract":"A Data Fusion (DF) approach for noise reduction in a system of multiple MEMS inclinometers is presented. The outputs of four inclinometers (ST IIS2CLX), that are nominally identical and set with the same operative conditions, have been acquired for 48 h consecutively. Each acquired dataset has been studied separately employing the Overlapping Allan VARiance (OAVAR) analysis to identify the Velocity Random Walk (VRW) and the Bias Instability (BI) noise contributions. The DF approach based on ensemble averaging across samples has been then applied combining the four acquired datasets, thus creating new datasets DFn, that contain averaged output data of n inclinometers at each acquisition time. The VRW and BI noise contributions of the DFn datasets have been identified through the OAVAR analysis and compared with the noise contributions of single inclinometers. Experimental results have shown a reduction of the noise variance σ2n for both the BI and VRW with a factor 1/n or, equivalently, the noise deviation σn with a factor $1/sqrt n $, in good agreement with theoretical expectations.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127343978","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 : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787522
A. Sabater, Eric Bozeman, S. Hobbs
This work provides experimental demonstration of a bias calibration method for frequency modulated (FM) accelerometers, that, in the future, could be implemented in a real-time fashion. The foundation for this effort is theoretical work that found connections between bias shift and previously underutilized components of the noise spectrum of a relatively novel class of FM accelerometers. Information on the design, simulation, fabrication, and testing of these devices is provided. Based on experiments, it is found that while secondary components of the noise spectrum can be used to track bias drift, effectively monitoring shifts in the constituent oscillator’s frequency provides a better means to observe in-run bias drift. After removing long-term drift, the remaining stationary noise processes can be filtered using autoregressive methods. Within the limits of the experimental setup, the filtered response provides a Gaussian estimate of local gravity with a bias instability of 180 ng at 1,000 sec.
{"title":"Towards Real-Time Frequency Modulated Accelerometer Bias Calibration","authors":"A. Sabater, Eric Bozeman, S. Hobbs","doi":"10.1109/INERTIAL53425.2022.9787522","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787522","url":null,"abstract":"This work provides experimental demonstration of a bias calibration method for frequency modulated (FM) accelerometers, that, in the future, could be implemented in a real-time fashion. The foundation for this effort is theoretical work that found connections between bias shift and previously underutilized components of the noise spectrum of a relatively novel class of FM accelerometers. Information on the design, simulation, fabrication, and testing of these devices is provided. Based on experiments, it is found that while secondary components of the noise spectrum can be used to track bias drift, effectively monitoring shifts in the constituent oscillator’s frequency provides a better means to observe in-run bias drift. After removing long-term drift, the remaining stationary noise processes can be filtered using autoregressive methods. Within the limits of the experimental setup, the filtered response provides a Gaussian estimate of local gravity with a bias instability of 180 ng at 1,000 sec.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127482669","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 : 2022-05-08DOI: 10.1109/INERTIAL53425.2022.9787749
Tianfang Peng, Zheng You
High-g shock is a critical challenge for MEMS. The acceleration that eventually acts on the microstructure of MEMS is usually different from the original shock in terms of amplitude and frequency due to factors like mounting and packaging. This inconsistency makes it difficult to measure the shocks accurately and assess the reliability of MEMS. This paper proposes a system-level transfer model of shock for MEMS in actual working conditions based on the lumped mechanical system model. Numerical and experimental results validated the effectiveness of this model. Mounting and packaging methods, which may influence the transfer process of high-g shock, were then analyzed. Several shock-resistant suggestions based on our model were proposed and experimentally validated.
{"title":"A Transfer Model of High-G Shock for MEMS in Real Working Conditions","authors":"Tianfang Peng, Zheng You","doi":"10.1109/INERTIAL53425.2022.9787749","DOIUrl":"https://doi.org/10.1109/INERTIAL53425.2022.9787749","url":null,"abstract":"High-g shock is a critical challenge for MEMS. The acceleration that eventually acts on the microstructure of MEMS is usually different from the original shock in terms of amplitude and frequency due to factors like mounting and packaging. This inconsistency makes it difficult to measure the shocks accurately and assess the reliability of MEMS. This paper proposes a system-level transfer model of shock for MEMS in actual working conditions based on the lumped mechanical system model. Numerical and experimental results validated the effectiveness of this model. Mounting and packaging methods, which may influence the transfer process of high-g shock, were then analyzed. Several shock-resistant suggestions based on our model were proposed and experimentally validated.","PeriodicalId":435781,"journal":{"name":"2022 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117313165","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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