Pub Date : 2018-03-01DOI: 10.1109/ISISS.2018.8358118
Y. Litmanovich, T. Paderina, Y. Binder
This paper further develops the new approach for compensation of the motion induced disturbances in dead reckoning navigation that was recently suggested by one of the authors [1], [2] and then presented internationally [3],[4]. The approach is alternative to the conventional one when an INS-type AHRS is used to provide attitude and heading data in order to transform the velocity components to the geographical frame. The new approach which was named Indirectly Correctable Pendulum (ICP) uses two techniques: one — is the construction of one-channel inertial vertical based on two vector observation. In doing so one vector is the specific force vector and the vertical is constructed in the plane that contains true vertical and the second vector regardless of its nature. The natural frequency of the inertial loop is defined by the nature of the second vector and can differ from the Schuler one. The second technique includes the compensation of the motion induced disturbances in the tilt angles generated from the accelerometer outputs but provided in the position components using the log data and the motion acceleration component generated in the inertial vertical channel. As a result the higher navigation accuracy and/or the reduced amount of gyros as compared to the conventional solution can be achieved.
{"title":"Attitude determination in dead reckoning navigation with reduced inertial support","authors":"Y. Litmanovich, T. Paderina, Y. Binder","doi":"10.1109/ISISS.2018.8358118","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358118","url":null,"abstract":"This paper further develops the new approach for compensation of the motion induced disturbances in dead reckoning navigation that was recently suggested by one of the authors [1], [2] and then presented internationally [3],[4]. The approach is alternative to the conventional one when an INS-type AHRS is used to provide attitude and heading data in order to transform the velocity components to the geographical frame. The new approach which was named Indirectly Correctable Pendulum (ICP) uses two techniques: one — is the construction of one-channel inertial vertical based on two vector observation. In doing so one vector is the specific force vector and the vertical is constructed in the plane that contains true vertical and the second vector regardless of its nature. The natural frequency of the inertial loop is defined by the nature of the second vector and can differ from the Schuler one. The second technique includes the compensation of the motion induced disturbances in the tilt angles generated from the accelerometer outputs but provided in the position components using the log data and the motion acceleration component generated in the inertial vertical channel. As a result the higher navigation accuracy and/or the reduced amount of gyros as compared to the conventional solution can be achieved.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125877208","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}
MEMS (Micro-electro Mechanical Systems) accelerometers are wildly used in vibration and impact detecting. Piezoresistive accelerometer is one of the wildly used types of sensor on the market with normal air package. However, when it is used in high impact environment, its fragile sensitive parts might get damaged. In this paper, we tried to use non-conducting liquid instead of air to fill the package shell of piezoresistive accelerometer. Its sensitivity and measuring range were analyzed when the package shell was filled with glycerinum, cyclohexane and silicon oil, respectively. Its resonant frequencies with glycerinum, cyclohexane and silicon oil package were also analyzed. The conclusion is that the liquid package is more suitable than air package for the piezoresistive MEMS accelerometer in harsh environment.
{"title":"Liquid packaging effects on piezoresistive MEMS accelerometer","authors":"Xixiang Liu, Weile Jiang, Libo Zhao, Chen Jia, Mingzhi Yu, Zhuangde Jiang","doi":"10.1109/ISISS.2018.8358133","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358133","url":null,"abstract":"MEMS (Micro-electro Mechanical Systems) accelerometers are wildly used in vibration and impact detecting. Piezoresistive accelerometer is one of the wildly used types of sensor on the market with normal air package. However, when it is used in high impact environment, its fragile sensitive parts might get damaged. In this paper, we tried to use non-conducting liquid instead of air to fill the package shell of piezoresistive accelerometer. Its sensitivity and measuring range were analyzed when the package shell was filled with glycerinum, cyclohexane and silicon oil, respectively. Its resonant frequencies with glycerinum, cyclohexane and silicon oil package were also analyzed. The conclusion is that the liquid package is more suitable than air package for the piezoresistive MEMS accelerometer in harsh environment.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129883389","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358143
A. D’Alessandro, R. D'Anna, L. Greco, G. Passafiume, S. Scudero, S. Speciale, G. Vitale
We introduce the realization of the first European real-time urban seismic network based on Micro Electro-Mechanical Systems (MEMS) technology. The project is called Monitoring Earthquake through MEMS Sensors (MEMS) and encompass the installation of about 100 seismic station in the municipality of Acireale (Sicily, Italy). The stations, specifically designed and assembled, are equipped with a triaxial MEMS accelerometer, and gyroscope and GPS. In this paper we present the characteristics of the station and of the network. The main objective of the network is a rapid, post-earthquake disaster assessment through the automatic production of shake maps. The network also allow the implementation of an automatic recognition system for damage assessment from remotely piloted aircraft, and of a site-specific Earthquake Early Warning system.
{"title":"Monitoring Earthquake through MEMS Sensors (MEMS project) in the town of Acireale (Italy)","authors":"A. D’Alessandro, R. D'Anna, L. Greco, G. Passafiume, S. Scudero, S. Speciale, G. Vitale","doi":"10.1109/ISISS.2018.8358143","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358143","url":null,"abstract":"We introduce the realization of the first European real-time urban seismic network based on Micro Electro-Mechanical Systems (MEMS) technology. The project is called Monitoring Earthquake through MEMS Sensors (MEMS) and encompass the installation of about 100 seismic station in the municipality of Acireale (Sicily, Italy). The stations, specifically designed and assembled, are equipped with a triaxial MEMS accelerometer, and gyroscope and GPS. In this paper we present the characteristics of the station and of the network. The main objective of the network is a rapid, post-earthquake disaster assessment through the automatic production of shake maps. The network also allow the implementation of an automatic recognition system for damage assessment from remotely piloted aircraft, and of a site-specific Earthquake Early Warning system.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127149719","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358137
A. Mahmoud, M. Mahmoud, T. Mukherjee, G. Piazza
This paper reports on the impact of the design of the resonant cavity on the noise performance of Surface Acoustic Wave Gyroscopes (SAWG). Inherently matched SAWGs were built on Y-cut Lithium Niobate (LN). Differently from all prior SAWG demonstrations, a large mass formed by periodically placed Au pillars were made to vibrate in-plane (and not out-of-plane) so as to measure rotation orthogonal to the gyroscope surface. Two cavity sizes were investigated. The larger cavity SAWG provided better performance. The experimental data agree well with theoretical expectations, hence validating our models.
{"title":"Investigating the impact of resonant cavity design on surface acoustic wave gyroscope","authors":"A. Mahmoud, M. Mahmoud, T. Mukherjee, G. Piazza","doi":"10.1109/ISISS.2018.8358137","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358137","url":null,"abstract":"This paper reports on the impact of the design of the resonant cavity on the noise performance of Surface Acoustic Wave Gyroscopes (SAWG). Inherently matched SAWGs were built on Y-cut Lithium Niobate (LN). Differently from all prior SAWG demonstrations, a large mass formed by periodically placed Au pillars were made to vibrate in-plane (and not out-of-plane) so as to measure rotation orthogonal to the gyroscope surface. Two cavity sizes were investigated. The larger cavity SAWG provided better performance. The experimental data agree well with theoretical expectations, hence validating our models.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129714029","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358139
F. Maspero, V. F. López-Rey, L. Joet, S. Hentz, G. Langfelder
The work discusses methods for the characterization of the sensor-related offset drift component in MEMS capacitive accelerometers. It is shown how, even with discrete electronics, it is not trivial to isolate this contribution from electronic-related components, due to unavoidable electronics tolerances and drift. A method that involves the use of multiple (at least two), nominally identical boards, pre-characterized in terms of temperature drift, is shown to be effective in identifying sensor-related drift components with an accuracy as low as sub-50 μg/K. At the same time, the developed board reaches high-resolution performance, in order to clearly highlight the Brownian noise limit (40 μg/√Hz) in the tested consumer-grade accelerometers.
{"title":"Combined electronics and algorithm development for offset drift characterization in MEMS accelerometers","authors":"F. Maspero, V. F. López-Rey, L. Joet, S. Hentz, G. Langfelder","doi":"10.1109/ISISS.2018.8358139","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358139","url":null,"abstract":"The work discusses methods for the characterization of the sensor-related offset drift component in MEMS capacitive accelerometers. It is shown how, even with discrete electronics, it is not trivial to isolate this contribution from electronic-related components, due to unavoidable electronics tolerances and drift. A method that involves the use of multiple (at least two), nominally identical boards, pre-characterized in terms of temperature drift, is shown to be effective in identifying sensor-related drift components with an accuracy as low as sub-50 μg/K. At the same time, the developed board reaches high-resolution performance, in order to clearly highlight the Brownian noise limit (40 μg/√Hz) in the tested consumer-grade accelerometers.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130807192","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358135
T. Tsukamoto, Shuji Tanaka
This paper reports a method to apply virtual rotation to a whole angle gyroscope (WAG) using independently controlled CW and CCW mode oscillations. The method does not require any additional mechanisms for the virtual rotation, but only changes the target phase values of two phase locked loops (PLLs). The virtual rotation at about 0.163 Hz was successfully applied to the WAG, and the angle locking phenomenon could be resolved. The bias instability as small as 1.1°/hr was observed.
{"title":"Virtually rotated MEMS whole angle gyroscope using independently controlled CW/CCW oscillations","authors":"T. Tsukamoto, Shuji Tanaka","doi":"10.1109/ISISS.2018.8358135","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358135","url":null,"abstract":"This paper reports a method to apply virtual rotation to a whole angle gyroscope (WAG) using independently controlled CW and CCW mode oscillations. The method does not require any additional mechanisms for the virtual rotation, but only changes the target phase values of two phase locked loops (PLLs). The virtual rotation at about 0.163 Hz was successfully applied to the WAG, and the angle locking phenomenon could be resolved. The bias instability as small as 1.1°/hr was observed.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130292593","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358130
T. Perrier, R. Lévy, P. Kayser, B. Verlhac, J. Moulin
This paper describes a fully analytic model of sensitivity of a vibrating magnetometer partially covered with a ferromagnetic thin film. This model is based on the Rayleigh's energetic method and is confirmed by Finite Element Method (FEM) and experimental measurements. Thereby, it is possible to optimize the position of the ferromagnetic thin film and find the best tradeoff between the sensitivity increase and the reduction of resonator energy losses to achieve better resolution.
{"title":"Modeling of a vibrating MEMS magnetometer partially covered with a ferromagnetic thin film","authors":"T. Perrier, R. Lévy, P. Kayser, B. Verlhac, J. Moulin","doi":"10.1109/ISISS.2018.8358130","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358130","url":null,"abstract":"This paper describes a fully analytic model of sensitivity of a vibrating magnetometer partially covered with a ferromagnetic thin film. This model is based on the Rayleigh's energetic method and is confirmed by Finite Element Method (FEM) and experimental measurements. Thereby, it is possible to optimize the position of the ferromagnetic thin film and find the best tradeoff between the sensitivity increase and the reduction of resonator energy losses to achieve better resolution.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"9 12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114777597","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358136
P. Minotti, G. Mussi, G. Langfelder, V. Zega, S. Facchinetti, A. Tocchio
Conventional MEMS vibratory gyroscopes rely on detecting the Coriolis-induced displacement amplitude along three orthogonal modes of a micro-mechanical structure. In recent years, an alternative approach based on frequency modulation, where the rate modulates the resonance frequency of the structure, has been proposed. This work tackles, from a system-level point of view, a comparison between the two solutions, aiming at a fair review of their main properties, advantages and drawbacks. The manuscript mainly focuses on low-power architectural aspects, on the sensitivity of the transduction principle against process and temperature variations, and on critical aspects related to the analog-to-digital conversion and the signal demodulation. Examples of experimental results enrich the discussion.
{"title":"A system-level comparison of amplitude-vs frequency-modulation approaches exploited in low-power MEMS vibratory gyroscopes","authors":"P. Minotti, G. Mussi, G. Langfelder, V. Zega, S. Facchinetti, A. Tocchio","doi":"10.1109/ISISS.2018.8358136","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358136","url":null,"abstract":"Conventional MEMS vibratory gyroscopes rely on detecting the Coriolis-induced displacement amplitude along three orthogonal modes of a micro-mechanical structure. In recent years, an alternative approach based on frequency modulation, where the rate modulates the resonance frequency of the structure, has been proposed. This work tackles, from a system-level point of view, a comparison between the two solutions, aiming at a fair review of their main properties, advantages and drawbacks. The manuscript mainly focuses on low-power architectural aspects, on the sensitivity of the transduction principle against process and temperature variations, and on critical aspects related to the analog-to-digital conversion and the signal demodulation. Examples of experimental results enrich the discussion.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126136456","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358150
Jörg F. Wagner
The “Machine of Bohnenberger” is considered to be the first gyro with cardanic suspension. As this apparatus forms the precursor of Foucault's Gyroscope of 1852, it rates as the ancestor of all gyroscopic instruments. Its inventor, Johann Gottlieb Friedrich Bohnenberger (1765–1831), was a professor of physics, mathematics, and astronomy at the University of Tübingen, Germany, as well as the scientific head-surveying officer of the early Kingdom of Württemberg. Being the direct counterpart of C.F. Gauß in south-west Germany, he made major contributions to introducing modern geodesy in Germany; and besides his Machine, he designed also other various physical instruments. The paper gives an overview over the initial dissemination and the further development of the Machine of Bohnenberger and outlines Bohnenberger's scientific work and life.
{"title":"The Machine of Bohnenberger: Inertial link between astronomy, navigation, and geodesy","authors":"Jörg F. Wagner","doi":"10.1109/ISISS.2018.8358150","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358150","url":null,"abstract":"The “Machine of Bohnenberger” is considered to be the first gyro with cardanic suspension. As this apparatus forms the precursor of Foucault's Gyroscope of 1852, it rates as the ancestor of all gyroscopic instruments. Its inventor, Johann Gottlieb Friedrich Bohnenberger (1765–1831), was a professor of physics, mathematics, and astronomy at the University of Tübingen, Germany, as well as the scientific head-surveying officer of the early Kingdom of Württemberg. Being the direct counterpart of C.F. Gauß in south-west Germany, he made major contributions to introducing modern geodesy in Germany; and besides his Machine, he designed also other various physical instruments. The paper gives an overview over the initial dissemination and the further development of the Machine of Bohnenberger and outlines Bohnenberger's scientific work and life.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"195 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124344428","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 : 2018-03-01DOI: 10.1109/ISISS.2018.8358145
Y. Tang, K. Najafi
This paper presents the implementation and preliminary characterization of a new type of digital accelerometer array with high detection resolution and low noise, enabled by high aspect-ratio (HAR) silicon proof-mass, dense sensor array, precisely-defined air-gaps and small air damping. We fabricated and tested 16-element (4-bit) and 32-element (5-bit) threshold accelerometer arrays (chip area <1 cm2) with evenly-spaced threshold air-gaps from 1–4 μm and incremental air-gaps as small as 100 nm. Vertically anchored springs of different cross-sectional dimensions (102–30μm2) are further designed to target specific g-ranges from < 100 mg to 40 g. The digital accelerometer chips are fabricated using a modified silicon-on-glass (SOG) process which provides tall (1mm) and HAR proof-mass within small footprint (>2.33 milligram/mm2), thus increasing the array density and reducing chip area while achieving Brownian noise equivalent acceleration (BNEA) at <1μg.
{"title":"High-density wide-range digital accelerometer arrays with high detection resolution","authors":"Y. Tang, K. Najafi","doi":"10.1109/ISISS.2018.8358145","DOIUrl":"https://doi.org/10.1109/ISISS.2018.8358145","url":null,"abstract":"This paper presents the implementation and preliminary characterization of a new type of digital accelerometer array with high detection resolution and low noise, enabled by high aspect-ratio (HAR) silicon proof-mass, dense sensor array, precisely-defined air-gaps and small air damping. We fabricated and tested 16-element (4-bit) and 32-element (5-bit) threshold accelerometer arrays (chip area <1 cm2) with evenly-spaced threshold air-gaps from 1–4 μm and incremental air-gaps as small as 100 nm. Vertically anchored springs of different cross-sectional dimensions (102–30μm2) are further designed to target specific g-ranges from < 100 mg to 40 g. The digital accelerometer chips are fabricated using a modified silicon-on-glass (SOG) process which provides tall (1mm) and HAR proof-mass within small footprint (>2.33 milligram/mm2), thus increasing the array density and reducing chip area while achieving Brownian noise equivalent acceleration (BNEA) at <1μg.","PeriodicalId":237642,"journal":{"name":"2018 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"90 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115774045","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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