Pub Date : 1992-03-23DOI: 10.1109/PLANS.1992.185900
B. Stein, M.L. Tsang
Summary form only given. The usual techniques of satellite attitude determination, such as utilizing inertial guidance components, are fairly expensive, especially if high accuracies are required for the mission. The authors explore a lower-cost alternative yielding equal or better accuracies, reliability, and repeatability. The approach under consideration utilizes the Global Positioning System (GPS) with either multiple antennas for one or more receivers spaced appropriately on the outer surface of the spacecraft. Consideration has also been given to supplementing GPS with the Global Navigation Satellite System (GLONASS) in order to increase the number of satellites visible at all times. The effects of this combination are discussed not only in terms of coverage but also to whether accuracy is enhanced or degraded due to the inherent characteristics of GLONASS. It has been demonstrated by simulation that satellite attitude determination using GPS is feasible, practical, and cost-effective for a variety of missions.<>
{"title":"Satellite attitude determination using GPS","authors":"B. Stein, M.L. Tsang","doi":"10.1109/PLANS.1992.185900","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185900","url":null,"abstract":"Summary form only given. The usual techniques of satellite attitude determination, such as utilizing inertial guidance components, are fairly expensive, especially if high accuracies are required for the mission. The authors explore a lower-cost alternative yielding equal or better accuracies, reliability, and repeatability. The approach under consideration utilizes the Global Positioning System (GPS) with either multiple antennas for one or more receivers spaced appropriately on the outer surface of the spacecraft. Consideration has also been given to supplementing GPS with the Global Navigation Satellite System (GLONASS) in order to increase the number of satellites visible at all times. The effects of this combination are discussed not only in terms of coverage but also to whether accuracy is enhanced or degraded due to the inherent characteristics of GLONASS. It has been demonstrated by simulation that satellite attitude determination using GPS is feasible, practical, and cost-effective for a variety of missions.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127452772","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185858
P. Ward, M. Jeerage
The authors describe the Texas Instruments/Honeywell Phase 1 Global Positioning System (GPS) Guidance Package (GGP) architecture and performance characteristics. The GGP is a tightly coupled, integrated miniature GPS receiver (MGR) and miniature inertial measurement unit (MIMU) capable of performing precision navigation, time coordination, mission management, and flight control for a broad class of Department of Defense platforms. These include strike weapons, unmanned airborne vehicles, and avionics platforms. The MGR architecture contains a highly integrated six-channel (expandable to eight channels) L1/L2 P(Y) code precise positioning service receiver/processor packaged on a single wiring board. The MGR design features a low-power GaAs integrated front end. The MIMU contains three interferometric fiber-optic gyros and three solid-state accelerometers in an inertial sensor assembly plus associated electronics and a microprocessor. The remaining GGP architecture consists of a data processor/data bus unit (DP/DBU) and an adaptable interface unit (AIU). The DP/DBU performs the tightly coupled, integrated navigation function. It has reserve memory and throughput cavity to perform mission management and flight control functions. The AIU supports numerous standard interfaces.<>
{"title":"The Texas Instruments/Honeywell GPS Guidance Package","authors":"P. Ward, M. Jeerage","doi":"10.1109/PLANS.1992.185858","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185858","url":null,"abstract":"The authors describe the Texas Instruments/Honeywell Phase 1 Global Positioning System (GPS) Guidance Package (GGP) architecture and performance characteristics. The GGP is a tightly coupled, integrated miniature GPS receiver (MGR) and miniature inertial measurement unit (MIMU) capable of performing precision navigation, time coordination, mission management, and flight control for a broad class of Department of Defense platforms. These include strike weapons, unmanned airborne vehicles, and avionics platforms. The MGR architecture contains a highly integrated six-channel (expandable to eight channels) L1/L2 P(Y) code precise positioning service receiver/processor packaged on a single wiring board. The MGR design features a low-power GaAs integrated front end. The MIMU contains three interferometric fiber-optic gyros and three solid-state accelerometers in an inertial sensor assembly plus associated electronics and a microprocessor. The remaining GGP architecture consists of a data processor/data bus unit (DP/DBU) and an adaptable interface unit (AIU). The DP/DBU performs the tightly coupled, integrated navigation function. It has reserve memory and throughput cavity to perform mission management and flight control functions. The AIU supports numerous standard interfaces.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127781050","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185824
N. Kouguchi, M. Sato, N. Morinaga
The Loran-C system suffers an individual additional secondary factor (ASF) error on each propagation path from a transmitter to a receiver. The authors propose a method to predict ASF error values using self-contained pulse distortion measures (change of half cycle length and envelope-to-cycle difference) on the received waves and show that the ASF error over mixed propagation paths can be reduced by these distortion measures. They describe a measurement technique for Loran-C pulse wave distortion measures and present analysis and simulation results of the performances of those measures in an environment of AWGN (additive white Gaussian noise) models.<>
{"title":"Measurement technique for Loran-C pulse wave distortion measures and performance in an environment of noise","authors":"N. Kouguchi, M. Sato, N. Morinaga","doi":"10.1109/PLANS.1992.185824","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185824","url":null,"abstract":"The Loran-C system suffers an individual additional secondary factor (ASF) error on each propagation path from a transmitter to a receiver. The authors propose a method to predict ASF error values using self-contained pulse distortion measures (change of half cycle length and envelope-to-cycle difference) on the received waves and show that the ASF error over mixed propagation paths can be reduced by these distortion measures. They describe a measurement technique for Loran-C pulse wave distortion measures and present analysis and simulation results of the performances of those measures in an environment of AWGN (additive white Gaussian noise) models.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131406229","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185821
D.N. Pittman, C. Roberts
To validate the self-calibration performance of a missile system's inertial navigation system (INS), an inertial error estimator (IEE) and a calibration procedure were developed and tested. The IEE was developed using a least squares fit of navigation-in-place data to calculate the accelerometer biases, the gyroscope biases, and the axis misalignments. It was found that the estimation error due to highly correlated regression functions decreases with navigation time. A tradeoff study was performed to select the optimum navigation-in-place time allowed for determining the estimation of the inertial errors. Once the optimum navigation time was determined, an INS calibration procedure incorporating the IEE was developed. The calibration procedure was validated by applying corrections for the inertial errors to the INS, and then navigating in place to show a reduced position error profile. Test results showing the outcome of the INS calibration procedure are included.<>
{"title":"Determining inertial errors from navigation-in-place data","authors":"D.N. Pittman, C. Roberts","doi":"10.1109/PLANS.1992.185821","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185821","url":null,"abstract":"To validate the self-calibration performance of a missile system's inertial navigation system (INS), an inertial error estimator (IEE) and a calibration procedure were developed and tested. The IEE was developed using a least squares fit of navigation-in-place data to calculate the accelerometer biases, the gyroscope biases, and the axis misalignments. It was found that the estimation error due to highly correlated regression functions decreases with navigation time. A tradeoff study was performed to select the optimum navigation-in-place time allowed for determining the estimation of the inertial errors. Once the optimum navigation time was determined, an INS calibration procedure incorporating the IEE was developed. The calibration procedure was validated by applying corrections for the inertial errors to the INS, and then navigating in place to show a reduced position error profile. Test results showing the outcome of the INS calibration procedure are included.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122890073","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185843
M.A.G. Peters
The National Aerospace Laboratory (NLR) has been awarded a contract by the Netherlands Ministry of Defense for the investigation and development of a TRN/INS/GPS (terrain reference navigation system/inertial navigation system/Global Positioning System) integrated navigation system. The integrated system should be capable of providing degraded modes. The three navigation sensors and a dedicated processing unit (for data merging) were configured around a MIL-STD-1553B digital data bus. Due to the inherent complexity of the integrated navigation system, much emphasis was given to careful testing of this system. Initial flight test results indicate that the integrated navigation system showed good performance, even when the performance of the individual sensors was deteriorated.<>
{"title":"Development of a TRN/INS/GPS integrated navigation system","authors":"M.A.G. Peters","doi":"10.1109/PLANS.1992.185843","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185843","url":null,"abstract":"The National Aerospace Laboratory (NLR) has been awarded a contract by the Netherlands Ministry of Defense for the investigation and development of a TRN/INS/GPS (terrain reference navigation system/inertial navigation system/Global Positioning System) integrated navigation system. The integrated system should be capable of providing degraded modes. The three navigation sensors and a dedicated processing unit (for data merging) were configured around a MIL-STD-1553B digital data bus. Due to the inherent complexity of the integrated navigation system, much emphasis was given to careful testing of this system. Initial flight test results indicate that the integrated navigation system showed good performance, even when the performance of the individual sensors was deteriorated.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"277 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122127502","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185878
D.A. Karnick
A concept being explored is the use of an inexpensive IMU (inertial measuring unit) with the GPS (Global Positioning System). An inexpensive IMU can meet many of the same functional requirements as the high-accuracy system, with the exception of long-term position. For example, some applications for instrumenting a reference frame are antenna stability, satellite acquisition (including GPS), platform stability, flight stabilization, and heading information. The acceleration data could still be integrated to find velocity and position; however, this position information would only be used for a period of minutes. For example, to provide continuous navigation during a GPS blockage due to buildings, wing blockage during a maneuver, etc. The author presents the capabilities of a unit of this type which was developed for the US Army.<>
{"title":"Low cost inertial measuring unit","authors":"D.A. Karnick","doi":"10.1109/PLANS.1992.185878","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185878","url":null,"abstract":"A concept being explored is the use of an inexpensive IMU (inertial measuring unit) with the GPS (Global Positioning System). An inexpensive IMU can meet many of the same functional requirements as the high-accuracy system, with the exception of long-term position. For example, some applications for instrumenting a reference frame are antenna stability, satellite acquisition (including GPS), platform stability, flight stabilization, and heading information. The acceleration data could still be integrated to find velocity and position; however, this position information would only be used for a period of minutes. For example, to provide continuous navigation during a GPS blockage due to buildings, wing blockage during a maneuver, etc. The author presents the capabilities of a unit of this type which was developed for the US Army.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128611832","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185865
M. Stamenkovich
A neural network model based on reinforcement learning is investigated for use as a shipboard autonomous channel navigator. The model used consists of two neuron-like elements. The basic learning scheme involves learning with a critic. The network consists of an adaptive critic element (ACE) and an adaptive search element (ASE). The ASE explores the channel region while the ACE criticizes the actions of the ASE and tries to predict failures of the ASE's attempt to navigate. The neural network model developed has been shown to be useful through software simulation with graphical feedback. A similar implementation could have applications in many electronic mapping systems utilizing vector information. The performance of such a system and its adaptability to new channels are investigated.<>
{"title":"An application of artificial neural networks for autonomous ship navigation through a channel","authors":"M. Stamenkovich","doi":"10.1109/PLANS.1992.185865","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185865","url":null,"abstract":"A neural network model based on reinforcement learning is investigated for use as a shipboard autonomous channel navigator. The model used consists of two neuron-like elements. The basic learning scheme involves learning with a critic. The network consists of an adaptive critic element (ACE) and an adaptive search element (ASE). The ASE explores the channel region while the ACE criticizes the actions of the ASE and tries to predict failures of the ASE's attempt to navigate. The neural network model developed has been shown to be useful through software simulation with graphical feedback. A similar implementation could have applications in many electronic mapping systems utilizing vector information. The performance of such a system and its adaptability to new channels are investigated.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128079700","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185861
L.W. Stimac, T. A. Kennedy
To achieve a particular set of motion compensation requirements and transfer alignment requirements a device called a motion sensor subsystem (MSS) was developed. The MSS is a strapdown inertial navigation system coupled with two decentralized Kalman filters that perform transfer alignment and estimation of various SINS instrument errors and system angular misalignments. One Kalman filter transfer aligns the MSS to the master navigator and the other filter estimates and corrects the misalignments between the MSS instrument axes and the sensor axes. The design, simulation, implementation, and flight testing of the MSS are described. These filters are coupled together through a process called regeneration that transfers one filter's shared state estimate to the other. In addition, because the filters operate in a closed-loop system, the computational time delay incurred by the filters significantly affects loop stability. A method of providing loop stability is discussed. The results of the MSS flight test have shown that using a methodology for developing a large Kalman filter based on intensive system covariance analysis and Monte Carlo simulation yields a system design that meets requirements.<>
{"title":"Sensor alignment Kalman filters for inertial stabilization systems","authors":"L.W. Stimac, T. A. Kennedy","doi":"10.1109/PLANS.1992.185861","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185861","url":null,"abstract":"To achieve a particular set of motion compensation requirements and transfer alignment requirements a device called a motion sensor subsystem (MSS) was developed. The MSS is a strapdown inertial navigation system coupled with two decentralized Kalman filters that perform transfer alignment and estimation of various SINS instrument errors and system angular misalignments. One Kalman filter transfer aligns the MSS to the master navigator and the other filter estimates and corrects the misalignments between the MSS instrument axes and the sensor axes. The design, simulation, implementation, and flight testing of the MSS are described. These filters are coupled together through a process called regeneration that transfers one filter's shared state estimate to the other. In addition, because the filters operate in a closed-loop system, the computational time delay incurred by the filters significantly affects loop stability. A method of providing loop stability is discussed. The results of the MSS flight test have shown that using a methodology for developing a large Kalman filter based on intensive system covariance analysis and Monte Carlo simulation yields a system design that meets requirements.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128035793","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185835
B. R. Climie
The International Civil Aviation Organization (ICAO) has developed a concept for an integrated, global air navigation system focused on satellite technology for the 21st Century. Automatic dependent surveillance (ADS) is a key element of this system and the center of integration. ADS extracts aircraft position and intent information from the onboard navigation system and transmits these vital data by means of automatic data link systems to ground facilities. Further, the ADS functionality is being integrated into multifunction software. In future aircraft, such as the Boeing B-777, the software will use robust partitioning techniques supported by a multifunction host computer. In other applications, ADS is being incorporated as another function within existing flight management computers. Civil aviation administrations and aircraft operators see ADS as the vehicle for early and significant improvements in safety and efficiency in air traffic management.<>
{"title":"Automatic dependent surveillance focus of civil avionics integration","authors":"B. R. Climie","doi":"10.1109/PLANS.1992.185835","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185835","url":null,"abstract":"The International Civil Aviation Organization (ICAO) has developed a concept for an integrated, global air navigation system focused on satellite technology for the 21st Century. Automatic dependent surveillance (ADS) is a key element of this system and the center of integration. ADS extracts aircraft position and intent information from the onboard navigation system and transmits these vital data by means of automatic data link systems to ground facilities. Further, the ADS functionality is being integrated into multifunction software. In future aircraft, such as the Boeing B-777, the software will use robust partitioning techniques supported by a multifunction host computer. In other applications, ADS is being incorporated as another function within existing flight management computers. Civil aviation administrations and aircraft operators see ADS as the vehicle for early and significant improvements in safety and efficiency in air traffic management.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127572673","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 : 1992-03-23DOI: 10.1109/PLANS.1992.185842
A. Brown, G. Moy
A strapdown stellar-inertial navigation system (INS) is currently being developed which can be used to correct for the gyro drift in an INS throughout a long-duration mission. The star sensor provides updates of the inertial angle error derived from stellar observations. However, since the star sensor updates are unable to correct for INS drifts due to accelerometer errors, the stellar inertial navigation solution accuracy degrades with time. A study has been performed on the number of visible satellites that can be tracked by the stellar-inertial system. The authors discuss the results of this study and include simulation results showing the performance improvement possible using both star and satellite observations to bound the system error growth. The results have shown that the combination of measurements can maintain the system error growth to within 700 ft over a long-duration mission.<>
{"title":"Long duration strapdown stellar-inertial navigation using satellite tracking","authors":"A. Brown, G. Moy","doi":"10.1109/PLANS.1992.185842","DOIUrl":"https://doi.org/10.1109/PLANS.1992.185842","url":null,"abstract":"A strapdown stellar-inertial navigation system (INS) is currently being developed which can be used to correct for the gyro drift in an INS throughout a long-duration mission. The star sensor provides updates of the inertial angle error derived from stellar observations. However, since the star sensor updates are unable to correct for INS drifts due to accelerometer errors, the stellar inertial navigation solution accuracy degrades with time. A study has been performed on the number of visible satellites that can be tracked by the stellar-inertial system. The authors discuss the results of this study and include simulation results showing the performance improvement possible using both star and satellite observations to bound the system error growth. The results have shown that the combination of measurements can maintain the system error growth to within 700 ft over a long-duration mission.<<ETX>>","PeriodicalId":422101,"journal":{"name":"IEEE PLANS 92 Position Location and Navigation Symposium Record","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131795076","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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