Pub Date : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511780
M. Pini, Alex Minetto, Andrea Vesco, D. Berbecaru, L. M. C. Murillo, P. Nemry, Ivan De Francesca, B. Rat, K. Callewaert
Satellite-derived timing information plays a determinant role in the provisioning of an absolute time reference to telecommunications networks, as well as in a growing set of other critical infrastructures. In light of the stringent requirements in terms of time, frequency, and phase synchronization foreseen in upcoming access network architectures (i.e., 5G), Global Navigation Satellite System (GNSS) receivers are expected to ensure enhanced accuracy and reliability not only in positioning but also in timing. High-end GNSS timing receivers combined with terrestrial cesium clocks and specific transport protocols can indeed satisfy such synchronization requirements by granting sub-nanosecond accuracy. As a drawback, the network infrastructure can be exposed to accidental interferences and intentional cyber-attacks. Within this framework, the ROOT project investigates the effectiveness and robustness of innovative countermeasures to GNSS and cybersecurity threats within a reference network architecture.
{"title":"Satellite-derived Time for Enhanced Telecom Networks Synchronization: the ROOT Project","authors":"M. Pini, Alex Minetto, Andrea Vesco, D. Berbecaru, L. M. C. Murillo, P. Nemry, Ivan De Francesca, B. Rat, K. Callewaert","doi":"10.1109/MetroAeroSpace51421.2021.9511780","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511780","url":null,"abstract":"Satellite-derived timing information plays a determinant role in the provisioning of an absolute time reference to telecommunications networks, as well as in a growing set of other critical infrastructures. In light of the stringent requirements in terms of time, frequency, and phase synchronization foreseen in upcoming access network architectures (i.e., 5G), Global Navigation Satellite System (GNSS) receivers are expected to ensure enhanced accuracy and reliability not only in positioning but also in timing. High-end GNSS timing receivers combined with terrestrial cesium clocks and specific transport protocols can indeed satisfy such synchronization requirements by granting sub-nanosecond accuracy. As a drawback, the network infrastructure can be exposed to accidental interferences and intentional cyber-attacks. Within this framework, the ROOT project investigates the effectiveness and robustness of innovative countermeasures to GNSS and cybersecurity threats within a reference network architecture.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121637075","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511731
M. Rosamilia, A. Aubry, V. Carotenuto, A. De Maio
The problem of missing sensor measurements can emerge in a variety of radar signal processing applications as for instance beamforming, direction of arrival estimation, interference cancellation, and target detection. The mentioned applications rely on reliable data covariance matrix estimates and suitable procedures, based on the expectation-maximization (EM) algorithm, have been proposed in the open literature to cope with the lack of some entries within specific spatial snapshots. In this paper, the effectiveness of a recent structured covariance matrix estimator [1], accounting for missing data and leveraging possible structural knowledge, is assessed on measured data. Specifically, the estimation procedure is framed in the context of two practically relevant radar applications: beamforming and detection of the number of sources. At the analysis stage, results highlight the effectiveness of the procedure to tackle missing data in the considered radar scenarios.
{"title":"Experimental Analysis of Structured Covariance Estimators with Missing data","authors":"M. Rosamilia, A. Aubry, V. Carotenuto, A. De Maio","doi":"10.1109/MetroAeroSpace51421.2021.9511731","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511731","url":null,"abstract":"The problem of missing sensor measurements can emerge in a variety of radar signal processing applications as for instance beamforming, direction of arrival estimation, interference cancellation, and target detection. The mentioned applications rely on reliable data covariance matrix estimates and suitable procedures, based on the expectation-maximization (EM) algorithm, have been proposed in the open literature to cope with the lack of some entries within specific spatial snapshots. In this paper, the effectiveness of a recent structured covariance matrix estimator [1], accounting for missing data and leveraging possible structural knowledge, is assessed on measured data. Specifically, the estimation procedure is framed in the context of two practically relevant radar applications: beamforming and detection of the number of sources. At the analysis stage, results highlight the effectiveness of the procedure to tackle missing data in the considered radar scenarios.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116323974","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511743
S. Liashkevich, V. Saetchnikov
The paper is devoted to the development of effective collaborative teaching and learning environment at the base of X-band university ground station for receiving weather satellites images. The purpose of the paper is to understand the process, technical and practical aspects of building ground-station for educational purposes. Open source design of ground station allow to form cooperation, where the final product is designed by the students. The proposed ground station is capable of tracking NOAA-20, Suomi-NPP, Terra, Aqua and other low orbit X-band operating satellites. The images presented reflect the results of ground station operation and show reasonably good quality.
{"title":"SDR Based X-Band University Ground Station as Remote Sensing Technologies Learning Environment","authors":"S. Liashkevich, V. Saetchnikov","doi":"10.1109/MetroAeroSpace51421.2021.9511743","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511743","url":null,"abstract":"The paper is devoted to the development of effective collaborative teaching and learning environment at the base of X-band university ground station for receiving weather satellites images. The purpose of the paper is to understand the process, technical and practical aspects of building ground-station for educational purposes. Open source design of ground station allow to form cooperation, where the final product is designed by the students. The proposed ground station is capable of tracking NOAA-20, Suomi-NPP, Terra, Aqua and other low orbit X-band operating satellites. The images presented reflect the results of ground station operation and show reasonably good quality.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124315372","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511712
L. Mariani, Paola Celesti, F. Curianò, L. Cimino, Luigi Di Palo, S. H. Hossein, M. Rossetti, Mascia Bucciarelli, G. Zarcone
With the advent of the new space economy, number of satellites orbiting around the Earth is growing exponentially, this consequently increase the impact risk between operative satellite and space debris. Sapienza Space Systems and Space Surveillance Laboratory has developed several software, strategies, and observation systems setup in order to identify, classify and monitor object in orbit. Using an extensive network of astronomical observatories located in various locations around the world the aggregation of raw data and measurements relating to a big number of optical surveys of the sky vault, S5lab manages to maintain a high degree of Space Situational Awareness regarding space surveillance. This paper will expose an overview of all methodologies, strategies and systems setup used by the research group to determinate attitude of a satellite or a space debris.
{"title":"Overview of optical observation strategies and systems: LEO and GEO measurements acquisition for position and attitude determination","authors":"L. Mariani, Paola Celesti, F. Curianò, L. Cimino, Luigi Di Palo, S. H. Hossein, M. Rossetti, Mascia Bucciarelli, G. Zarcone","doi":"10.1109/MetroAeroSpace51421.2021.9511712","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511712","url":null,"abstract":"With the advent of the new space economy, number of satellites orbiting around the Earth is growing exponentially, this consequently increase the impact risk between operative satellite and space debris. Sapienza Space Systems and Space Surveillance Laboratory has developed several software, strategies, and observation systems setup in order to identify, classify and monitor object in orbit. Using an extensive network of astronomical observatories located in various locations around the world the aggregation of raw data and measurements relating to a big number of optical surveys of the sky vault, S5lab manages to maintain a high degree of Space Situational Awareness regarding space surveillance. This paper will expose an overview of all methodologies, strategies and systems setup used by the research group to determinate attitude of a satellite or a space debris.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129015268","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511744
D. Capriglione, M. Carratù, M. Catelani, L. Ciani, G. Patrizi, A. Pietrosanto, R. Singuaroli, P. Sommella
The current technological process has mainly interested in integrating MEMS devices in most technological devices to offer complete control and awareness about a particular process or system. Such devices, which in most cases include gyroscope, accelerometer, and magnetometer, are fully integrated on a single chip and have a cost not higher than few dollars. Recently they have been more employed in embedded systems devoted to the autonomous driving operation for terrestrial and aeronautical vehicles. Such devices are often deployed to the market with datasheet reporting their characteristic without highlighting their behavior under particular environmental conditions. Most MEMS devices are mounted in a very harsh environment, characterized by high-temperature excursion and vibration from different sources. The authors propose a temperature stress test for such devices and evaluate their behavior under static conditions. Experimental results will evidence the accelerometer and gyroscope MEMS sensors' dependence on the temperature in a range of −10°C to 50°C.
{"title":"Analysis of MEMS devices under temperature stress test","authors":"D. Capriglione, M. Carratù, M. Catelani, L. Ciani, G. Patrizi, A. Pietrosanto, R. Singuaroli, P. Sommella","doi":"10.1109/MetroAeroSpace51421.2021.9511744","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511744","url":null,"abstract":"The current technological process has mainly interested in integrating MEMS devices in most technological devices to offer complete control and awareness about a particular process or system. Such devices, which in most cases include gyroscope, accelerometer, and magnetometer, are fully integrated on a single chip and have a cost not higher than few dollars. Recently they have been more employed in embedded systems devoted to the autonomous driving operation for terrestrial and aeronautical vehicles. Such devices are often deployed to the market with datasheet reporting their characteristic without highlighting their behavior under particular environmental conditions. Most MEMS devices are mounted in a very harsh environment, characterized by high-temperature excursion and vibration from different sources. The authors propose a temperature stress test for such devices and evaluate their behavior under static conditions. Experimental results will evidence the accelerometer and gyroscope MEMS sensors' dependence on the temperature in a range of −10°C to 50°C.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"420 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132872110","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511705
F. Sansone, Francesco Branz, Andrea Vettor, A. Francesconi
Small satellites are increasingly exploited for the realization of low Earth orbit (LEO) constellations for Earth imaging, global connectivity and data relay. Optical crosslinks between satellites can drastically increase the constellation capability to transmit data to ground stations with reduced latency and increased total throughput. One critical aspect of optical crosslink is the acquisition phase, which requires that each satellite scans its field of view looking for the beacon laser transmitted by the partner terminal before starting communication. In this paper, the problem of beacon acquisition for optical crosslinks is analyzed, with focus on the small satellite case. Numerical simulations and a simplified, yet representative laboratory experiment are carried out to evaluate and compare two different scanning techniques quantitatively.
{"title":"Acquisition Analysis for Small-Satellite Optical Crosslinks","authors":"F. Sansone, Francesco Branz, Andrea Vettor, A. Francesconi","doi":"10.1109/MetroAeroSpace51421.2021.9511705","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511705","url":null,"abstract":"Small satellites are increasingly exploited for the realization of low Earth orbit (LEO) constellations for Earth imaging, global connectivity and data relay. Optical crosslinks between satellites can drastically increase the constellation capability to transmit data to ground stations with reduced latency and increased total throughput. One critical aspect of optical crosslink is the acquisition phase, which requires that each satellite scans its field of view looking for the beacon laser transmitted by the partner terminal before starting communication. In this paper, the problem of beacon acquisition for optical crosslinks is analyzed, with focus on the small satellite case. Numerical simulations and a simplified, yet representative laboratory experiment are carried out to evaluate and compare two different scanning techniques quantitatively.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128084981","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511724
Z. Czyz, P. Karpiński, K. Skiba
The aerodynamic properties of propellers strictly depend on their geometry. Pitch is one of the key parameters defining propeller performance. This paper presents the results of a wind-tunnel investigation of the propellers for the unmanned aerial vehicle. In this paper, the performance of a set of 12-inch propellers with different pitch values for different values of air velocity was analyzed. The tests were performed on a specially designed test stand placed in a wind tunnel test chamber. The test stand enabled adjustment of the air velocity as well as the propeller rotational speed. An adequately selected set of sensors allowed to record the defined parameters. Obtained results allowed to evaluate the performance of the considered propellers with different pitch values in forced airflow conditions.
{"title":"Wind tunnel investigation of the propellers for unmanned aerial vehicle","authors":"Z. Czyz, P. Karpiński, K. Skiba","doi":"10.1109/MetroAeroSpace51421.2021.9511724","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511724","url":null,"abstract":"The aerodynamic properties of propellers strictly depend on their geometry. Pitch is one of the key parameters defining propeller performance. This paper presents the results of a wind-tunnel investigation of the propellers for the unmanned aerial vehicle. In this paper, the performance of a set of 12-inch propellers with different pitch values for different values of air velocity was analyzed. The tests were performed on a specially designed test stand placed in a wind tunnel test chamber. The test stand enabled adjustment of the air velocity as well as the propeller rotational speed. An adequately selected set of sensors allowed to record the defined parameters. Obtained results allowed to evaluate the performance of the considered propellers with different pitch values in forced airflow conditions.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129211658","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511773
M. Orefice, V. Quaranta, G. Bruno, Giuseppe Martinotti, Carmine Carandente Tartaglia
Satellites are designed and tested to withstand to static and dynamic operative loads during the launch and the ascent phase. The validation of the structural design of the satellite is generally performed by tests and/or analysis. The paper presents the static load test methods with a focus on the sine-burst quasi-static load test. A test procedure will be presented in order to overcome the main issues related to a sine-burst test. Finally test results performed on a 6U Cubesat will be discussed.
{"title":"Quasi-static load space qualification test","authors":"M. Orefice, V. Quaranta, G. Bruno, Giuseppe Martinotti, Carmine Carandente Tartaglia","doi":"10.1109/MetroAeroSpace51421.2021.9511773","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511773","url":null,"abstract":"Satellites are designed and tested to withstand to static and dynamic operative loads during the launch and the ascent phase. The validation of the structural design of the satellite is generally performed by tests and/or analysis. The paper presents the static load test methods with a focus on the sine-burst quasi-static load test. A test procedure will be presented in order to overcome the main issues related to a sine-burst test. Finally test results performed on a 6U Cubesat will be discussed.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128645515","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511742
P. Longobardi, G. Laupré, J. Skaloud
Vehicle Dynamic Model based navigation represents a novel approach to autonomous navigation for small UAVs. It significantly improves the navigation solution under GNSS outage condition without adding additional sensors to the platform. This paper proposes an alternative method for determination of the aerodynamic coefficients characterizing the system dynamics needed to enable VDM-based navigation. It relies on the usage of post-processed traditional INS/GNSS navigation solution for the estimation of initial values of the aerodynamic coefficients. The importance of optimal selection of experimental data is highlighted, proposing an evaluation criterion whose benefit is the increase of the statistical significance of the coefficient estimation.
{"title":"Aerodynamic characterization of a Delta-wing UAV based on real flight data processing","authors":"P. Longobardi, G. Laupré, J. Skaloud","doi":"10.1109/MetroAeroSpace51421.2021.9511742","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511742","url":null,"abstract":"Vehicle Dynamic Model based navigation represents a novel approach to autonomous navigation for small UAVs. It significantly improves the navigation solution under GNSS outage condition without adding additional sensors to the platform. This paper proposes an alternative method for determination of the aerodynamic coefficients characterizing the system dynamics needed to enable VDM-based navigation. It relies on the usage of post-processed traditional INS/GNSS navigation solution for the estimation of initial values of the aerodynamic coefficients. The importance of optimal selection of experimental data is highlighted, proposing an evaluation criterion whose benefit is the increase of the statistical significance of the coefficient estimation.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"362 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115561207","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 : 2021-06-23DOI: 10.1109/MetroAeroSpace51421.2021.9511682
A. Olejnik, R. Rogólski, M. Szczesniak
Measurement of vibrations of the entire aircraft or individual components is very important in the design and operation of aircraft. It should be known that the correct performance of such measurements requires specialized measuring devices, appropriate knowledge and experience. This paper presents two basic methods of measuring the vibration of realaircraft structures. The presented measuring apparatus are dedicated to the aviation industry. First, the apparatus for measuring vibrations with the contact method will be presented, and then with the non-contact method. The advantages and disadvantages of both methods will be presented and examples of application will be shown.
{"title":"Contact and non-contact methods of vibration measurement in aircraft structures","authors":"A. Olejnik, R. Rogólski, M. Szczesniak","doi":"10.1109/MetroAeroSpace51421.2021.9511682","DOIUrl":"https://doi.org/10.1109/MetroAeroSpace51421.2021.9511682","url":null,"abstract":"Measurement of vibrations of the entire aircraft or individual components is very important in the design and operation of aircraft. It should be known that the correct performance of such measurements requires specialized measuring devices, appropriate knowledge and experience. This paper presents two basic methods of measuring the vibration of realaircraft structures. The presented measuring apparatus are dedicated to the aviation industry. First, the apparatus for measuring vibrations with the contact method will be presented, and then with the non-contact method. The advantages and disadvantages of both methods will be presented and examples of application will be shown.","PeriodicalId":236783,"journal":{"name":"2021 IEEE 8th International Workshop on Metrology for AeroSpace (MetroAeroSpace)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122766343","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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