Pub Date : 2010-05-04DOI: 10.1109/PLANS.2010.5507133
Burgess R. Johnson, E. Cabuz, H. French, R. Supino
We report progress toward a MEMS gyroscope suitable for northfinding in pointing and targeting applications. In-run bias stability of 0.03 deg/hr and ARW of 0.002 deg/rt(hr) have been achieved. Gyro performance was measured on tuning-fork type MEMS gyroscopes using DSP-based breadboard electronics. These bias stability and ARW results are within about 6X and 2X, respectively, of meeting the typical gyrocompass requirements for pointing and targeting applications (1 milliradian azimuth precision at 65 degrees latitude with 5 minute integration time). A MEMS gyrocompass meeting these requirements would substantially reduce the size, weight and power of pointing and targeting instruments. The test methodology will be presented, as well as test data on carouseling the sensor to reduce the effects of long-term bias drift.
{"title":"Development of a MEMS gyroscope for northfinding applications","authors":"Burgess R. Johnson, E. Cabuz, H. French, R. Supino","doi":"10.1109/PLANS.2010.5507133","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507133","url":null,"abstract":"We report progress toward a MEMS gyroscope suitable for northfinding in pointing and targeting applications. In-run bias stability of 0.03 deg/hr and ARW of 0.002 deg/rt(hr) have been achieved. Gyro performance was measured on tuning-fork type MEMS gyroscopes using DSP-based breadboard electronics. These bias stability and ARW results are within about 6X and 2X, respectively, of meeting the typical gyrocompass requirements for pointing and targeting applications (1 milliradian azimuth precision at 65 degrees latitude with 5 minute integration time). A MEMS gyrocompass meeting these requirements would substantially reduce the size, weight and power of pointing and targeting instruments. The test methodology will be presented, as well as test data on carouseling the sensor to reduce the effects of long-term bias drift.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"21 1","pages":"168-170"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74040172","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507334
Yan Jiang, F. Gao, Guoyan Xu
We presented a multiple-lane detection system in this paper. To cope with both straight and curved road, the system recognized the road type based on the vehicle's GPS position and digital map data, and designated different schemes for detection. Unlike the known systems that have treated lane marking as a single entity, this system focused on the inner edge of the stripe to locate a vehicle in a lane accurately. The camera's installation parameters, especially the pitch angle, were estimated using the real-time detection results to compensate for changes in the vehicle's pose. Using an “estimate-detect” style, adjacent-lane markings were detected even when they were partly blocked by other vehicles.
{"title":"Self-calibrated multiple-lane detection system","authors":"Yan Jiang, F. Gao, Guoyan Xu","doi":"10.1109/PLANS.2010.5507334","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507334","url":null,"abstract":"We presented a multiple-lane detection system in this paper. To cope with both straight and curved road, the system recognized the road type based on the vehicle's GPS position and digital map data, and designated different schemes for detection. Unlike the known systems that have treated lane marking as a single entity, this system focused on the inner edge of the stripe to locate a vehicle in a lane accurately. The camera's installation parameters, especially the pitch angle, were estimated using the real-time detection results to compensate for changes in the vehicle's pose. Using an “estimate-detect” style, adjacent-lane markings were detected even when they were partly blocked by other vehicles.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"2 1","pages":"1052-1056"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79296897","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507129
M. Becker, U. Bestmann, A. Schwithal, P. Hecker, R. Bott, P. Kohl, S. Knedlik, H. Scheyer, E. V. Hinuber
The Inertial Measurement Unit (IMU) investigated within the presented work consists of two (optional three) dissimilar sets of MEMS accelerometers and gyros, respectively. Both sets are mounted in one enclosure and thus are subject to the same calibration procedure. Different combinations of these dual sensor sets can be used to exploit the complementary sensor properties, e.g. measurement range, resolution and noise characteristics as well as to benefit from redundancy in airborne applications.
{"title":"Evaluation of a double equipped MEMS IMU based on real flight trial scenarios","authors":"M. Becker, U. Bestmann, A. Schwithal, P. Hecker, R. Bott, P. Kohl, S. Knedlik, H. Scheyer, E. V. Hinuber","doi":"10.1109/PLANS.2010.5507129","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507129","url":null,"abstract":"The Inertial Measurement Unit (IMU) investigated within the presented work consists of two (optional three) dissimilar sets of MEMS accelerometers and gyros, respectively. Both sets are mounted in one enclosure and thus are subject to the same calibration procedure. Different combinations of these dual sensor sets can be used to exploit the complementary sensor properties, e.g. measurement range, resolution and noise characteristics as well as to benefit from redundancy in airborne applications.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"56 1","pages":"202-213"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83664565","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507318
Ping Luo, M. Petovello
Signal commonality among local GPS receivers is studied in this paper. More specifically, the GPS signal parameters, carrier Doppler, code phase and carrier to noise power density (C/N0), from different GPS receivers are investigated. It shows that as the antenna spacing is small (<30 meters) the code phase and carrier Doppler are quite in-common. The code phase falls into the same code bin, while the carrier Doppler difference is mainly due to the clock drifts from different receivers. It also shows that the C/N0 difference is within a certain range (more than 90% is less than 8dB). The impacts of imperfection of these parameters on GPS signal acquisition are then studied in terms of probability of detection and probability of false alarm. Based on the field measurements and the theoretical analysis, the potential advantage of collaborative GPS signal acquisition is present.
{"title":"Collaborative acquisition of weak GPS signals","authors":"Ping Luo, M. Petovello","doi":"10.1109/PLANS.2010.5507318","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507318","url":null,"abstract":"Signal commonality among local GPS receivers is studied in this paper. More specifically, the GPS signal parameters, carrier Doppler, code phase and carrier to noise power density (C/N0), from different GPS receivers are investigated. It shows that as the antenna spacing is small (<30 meters) the code phase and carrier Doppler are quite in-common. The code phase falls into the same code bin, while the carrier Doppler difference is mainly due to the clock drifts from different receivers. It also shows that the C/N0 difference is within a certain range (more than 90% is less than 8dB). The impacts of imperfection of these parameters on GPS signal acquisition are then studied in terms of probability of detection and probability of false alarm. Based on the field measurements and the theoretical analysis, the potential advantage of collaborative GPS signal acquisition is present.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"38 1","pages":"787-795"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80750402","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507220
M. Bitter, T. Feuerle, Benedikt von Wulfen, M. Steen, P. Hecker
Satellite based Navigation Systems (Global Navigation Satellite System GNSS) will become a major element in the navigation infrastructure of the future. In addition to classical en-route and terminal navigation, where GNSS is increasingly used, approach and landing procedures are being developed and implemented based on GNSS. To meet the requirements of integrity, accuracy, continuity and availability for precision approach and landing operations, augmentation systems are needed. Currently there are two augmentation systems for these periods of flight available: Ground Based Augmentation Systems (GBAS) and Space Based Augmentation Systems (SBAS).
{"title":"Testbed for dual-constellation GBAS concepts","authors":"M. Bitter, T. Feuerle, Benedikt von Wulfen, M. Steen, P. Hecker","doi":"10.1109/PLANS.2010.5507220","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507220","url":null,"abstract":"Satellite based Navigation Systems (Global Navigation Satellite System GNSS) will become a major element in the navigation infrastructure of the future. In addition to classical en-route and terminal navigation, where GNSS is increasingly used, approach and landing procedures are being developed and implemented based on GNSS. To meet the requirements of integrity, accuracy, continuity and availability for precision approach and landing operations, augmentation systems are needed. Currently there are two augmentation systems for these periods of flight available: Ground Based Augmentation Systems (GBAS) and Space Based Augmentation Systems (SBAS).","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"19 1","pages":"680-687"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80880846","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507292
D. Cho, Ho-Cheol Jeong, Sang Hyun Park
Currently many vessels determine an overhead clearance by a rule of thumb based on their draft for maritime navigation. Therefore when vessels navigate, they don't have a good overhead clearance because vertical position of vessels varies on time by tidal. As a result, it is occurred maritime accidents that the mainmast of vessels is bumped against overhead facilities. This paper evaluates precise GPS satellite ephemerides and clocks provided by the IGS for applying to maritime precise positioning. And this paper shows that it is necessary to have shorter interval IGS products in real-time for more precise positioning solution.
{"title":"Assessment of precise GPS ephemeris and clock in the International GNSS service","authors":"D. Cho, Ho-Cheol Jeong, Sang Hyun Park","doi":"10.1109/PLANS.2010.5507292","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507292","url":null,"abstract":"Currently many vessels determine an overhead clearance by a rule of thumb based on their draft for maritime navigation. Therefore when vessels navigate, they don't have a good overhead clearance because vertical position of vessels varies on time by tidal. As a result, it is occurred maritime accidents that the mainmast of vessels is bumped against overhead facilities. This paper evaluates precise GPS satellite ephemerides and clocks provided by the IGS for applying to maritime precise positioning. And this paper shows that it is necessary to have shorter interval IGS products in real-time for more precise positioning solution.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"1 1","pages":"137-141"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83019638","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507190
Yuwei Chen, Ruizhi Chen, L. Pei, T. Kroger, H. Kuusniemi, Jingbin Liu, Wei Chen
For pedestrian indoor navigation, an accurate 2D/3D position is a premise for any further processing. Currently, indoor navigation is a challenging task for standalone GNSS technology. FGI has integrated self-contained sensors with wireless locating technology to investigate a hybrid indoor positioning solution. However, the infrastructure indoors inflicts multiple disturbances to the positioning sensors. A knowledge-based error detection and correction method is applied to detect and eliminate the occurring gross errors. Six modes of user dynamics are extracted from measurements of a barometer and an accelerometer, and such contexts can improve the positioning accuracy and enhance the user experience of the final navigation application.
{"title":"Knowledge-based error detection and correction method of a Multi-sensor Multi-network positioning platform for pedestrian indoor navigation","authors":"Yuwei Chen, Ruizhi Chen, L. Pei, T. Kroger, H. Kuusniemi, Jingbin Liu, Wei Chen","doi":"10.1109/PLANS.2010.5507190","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507190","url":null,"abstract":"For pedestrian indoor navigation, an accurate 2D/3D position is a premise for any further processing. Currently, indoor navigation is a challenging task for standalone GNSS technology. FGI has integrated self-contained sensors with wireless locating technology to investigate a hybrid indoor positioning solution. However, the infrastructure indoors inflicts multiple disturbances to the positioning sensors. A knowledge-based error detection and correction method is applied to detect and eliminate the occurring gross errors. Six modes of user dynamics are extracted from measurements of a barometer and an accelerometer, and such contexts can improve the positioning accuracy and enhance the user experience of the final navigation application.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"76 1","pages":"873-879"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90792324","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507205
N. Shivaramaiah, A. Dempster
This paper extends the Sub-carrier Phase Combination technique previously presented by the authors to mitigate the effect of frequency selective Radio Frequency (RF) propagation delay distortions in Alternate Binary Offset Carrier (AltBOC) receivers. Two major propagation delay distortion sources are considered: the ionosphere and multipath. Initial analysis shows that the ionospheric delay errors can be reduced to being comparable to the receiver impairments (when the error due to multipath is low) and the maximum multipath error (under low ionospheric distortions) can be reduced to half a meter. Under extremely high ionospheric delay distortions, the multipath delay error envelope, with the proposed technique, will suffer no change in the magnitude of the error except that the spatial characteristics are different. The underlying idea of the proposed technique is that difference in the phase delays of the E5a and E5b signal tracking is simply the slope of the phase response over the entire band and hence represents the group delay at the E5 center frequency of 1191.795 MHz. The group delay which appears as the code phase error for the E5 signal tracking, can thus be compensated except for the occurrence of higher order errors
{"title":"Group delay compensation in AltBOC receivers to mitigate the effect of frequency selective propagation delay distortions","authors":"N. Shivaramaiah, A. Dempster","doi":"10.1109/PLANS.2010.5507205","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507205","url":null,"abstract":"This paper extends the Sub-carrier Phase Combination technique previously presented by the authors to mitigate the effect of frequency selective Radio Frequency (RF) propagation delay distortions in Alternate Binary Offset Carrier (AltBOC) receivers. Two major propagation delay distortion sources are considered: the ionosphere and multipath. Initial analysis shows that the ionospheric delay errors can be reduced to being comparable to the receiver impairments (when the error due to multipath is low) and the maximum multipath error (under low ionospheric distortions) can be reduced to half a meter. Under extremely high ionospheric delay distortions, the multipath delay error envelope, with the proposed technique, will suffer no change in the magnitude of the error except that the spatial characteristics are different. The underlying idea of the proposed technique is that difference in the phase delays of the E5a and E5b signal tracking is simply the slope of the phase response over the entire band and hence represents the group delay at the E5 center frequency of 1191.795 MHz. The group delay which appears as the code phase error for the E5 signal tracking, can thus be compensated except for the occurrence of higher order errors","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"13 1","pages":"227-235"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90979843","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507183
C. Griffith, P. Dare, Lee Danish
ShapeAccelArray (SAA) provides precise 3D position along a continuum using hundreds of low cost MEMS sensors. The technology has been applied to long term soil monitoring applications, where long-term accuracies in the 50 part-per-million (ppm) range have been achieved. Industrial demand for the technology in structural monitoring applications where 10 ppm would be desirable has magnified the importance of modelling and compensating for temperature sensitivities of each sensor. In such applications, dramatic temperature changes are possible, unlike the relatively stable, sub surface environment.
{"title":"Calibration enhancement of ShapeAccelArray technology for long term deformation monitoring applications","authors":"C. Griffith, P. Dare, Lee Danish","doi":"10.1109/PLANS.2010.5507183","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507183","url":null,"abstract":"ShapeAccelArray (SAA) provides precise 3D position along a continuum using hundreds of low cost MEMS sensors. The technology has been applied to long term soil monitoring applications, where long-term accuracies in the 50 part-per-million (ppm) range have been achieved. Industrial demand for the technology in structural monitoring applications where 10 ppm would be desirable has magnified the importance of modelling and compensating for temperature sensitivities of each sensor. In such applications, dramatic temperature changes are possible, unlike the relatively stable, sub surface environment.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"12 1","pages":"621-626"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89435053","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 : 2010-05-04DOI: 10.1109/PLANS.2010.5507223
S. Lo, P. Enge
This paper studies the feasibility and means by which authentication can be overlaid upon the existing SBAS and GBAS designs. It considers how to achieve the authentication that is compatible with the current augmentation system and its users. It also considers how to perform the security necessary to support authentication within the current NAS framework. One important issue is secure key distribution and the paper presents some options designed to be reasonable for aviation infrastructure and operations. One means is a key distribution protocol that utilizes the operation of the aircraft and air traffic to aid in key verification. This provides to distribute keys and provide some ability to validate them without significant additions to the NAS. Another issue is bandwidth. The paper presents ways of modifying protocols such as TESLA to reduce bandwidth use while maintaining an acceptable level of security. The paper uses the current L1 SBAS and GBAS as case studies. The paper presents reasonable method to provide authentication on the current SBAS using about ten percent of bandwidth. The method is compatible to current SBAS user equipment in that they will not be adversely affected. GBAS can employ similar means. As it has greater data bandwidth, a more critical issue for GBAS is key distribution to the ground stations.
{"title":"Authenticating aviation augmentation system broadcasts","authors":"S. Lo, P. Enge","doi":"10.1109/PLANS.2010.5507223","DOIUrl":"https://doi.org/10.1109/PLANS.2010.5507223","url":null,"abstract":"This paper studies the feasibility and means by which authentication can be overlaid upon the existing SBAS and GBAS designs. It considers how to achieve the authentication that is compatible with the current augmentation system and its users. It also considers how to perform the security necessary to support authentication within the current NAS framework. One important issue is secure key distribution and the paper presents some options designed to be reasonable for aviation infrastructure and operations. One means is a key distribution protocol that utilizes the operation of the aircraft and air traffic to aid in key verification. This provides to distribute keys and provide some ability to validate them without significant additions to the NAS. Another issue is bandwidth. The paper presents ways of modifying protocols such as TESLA to reduce bandwidth use while maintaining an acceptable level of security. The paper uses the current L1 SBAS and GBAS as case studies. The paper presents reasonable method to provide authentication on the current SBAS using about ten percent of bandwidth. The method is compatible to current SBAS user equipment in that they will not be adversely affected. GBAS can employ similar means. As it has greater data bandwidth, a more critical issue for GBAS is key distribution to the ground stations.","PeriodicalId":94036,"journal":{"name":"IEEE/ION Position Location and Navigation Symposium : [proceedings]. IEEE/ION Position Location and Navigation Symposium","volume":"1 1","pages":"708-717"},"PeriodicalIF":0.0,"publicationDate":"2010-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88066049","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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