Pub Date : 2012-09-24DOI: 10.1109/ISRCS.2012.6309316
C. Coopmans, B. Stark, C. M. Coffin
Small, unmanned aerial systems are becoming more important in many fields, including civilian, scientific applications. Affordable systems that allow remote sensing at a small scale-personal remote sensing-are possible with proper system design. To assure data mission success (i.e., reliable and safe data collection) with low-cost or consumer-level sensor hardware, a well-designed payload management system is needed, along with sensor interface development and standardized testing frameworks for verification. This payload management system ensures a level of airworthiness for Data Mission Assurance. This paper presents such a system, along with motivations and choices such as system architecture and implementation, as well as standardized testing and verification. Data results from flight of a fixed-wing example payload is also included.
{"title":"A payload verification and management framework for small UAV-based personal remote sensing systems","authors":"C. Coopmans, B. Stark, C. M. Coffin","doi":"10.1109/ISRCS.2012.6309316","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309316","url":null,"abstract":"Small, unmanned aerial systems are becoming more important in many fields, including civilian, scientific applications. Affordable systems that allow remote sensing at a small scale-personal remote sensing-are possible with proper system design. To assure data mission success (i.e., reliable and safe data collection) with low-cost or consumer-level sensor hardware, a well-designed payload management system is needed, along with sensor interface development and standardized testing frameworks for verification. This payload management system ensures a level of airworthiness for Data Mission Assurance. This paper presents such a system, along with motivations and choices such as system architecture and implementation, as well as standardized testing and verification. Data results from flight of a fixed-wing example payload is also included.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132636780","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309293
M. Yampolskiy, P. Horváth, X. Koutsoukos, Yuan Xue, J. Sztipanovits
Cyber-Physical Systems (CPSs) consist of as well as interact with cyber and physical elements. This creates multiple vectors for CPS-internal (i.e., within CPS) as well as for CPS-external (i.e., between CPS itself and its environment) Cyber-Physical Attacks. We argue that an effective Cyber-Physical Defense can only be elaborated if possible attacks on CPS can be identified and assessed in a systematic manner. In this paper, we focus on cyber-attacks only. Our contribution in this paper is the following. We assess the applicability of Data Flow Diagrams (DFD) for the systematic analysis of cyber-attacks against CPS. In this context, we introduce several extensions to DFD. We evaluate the analysis procedure by applying it on a comparatively simple example of a quad-rotor UAV. The selected UAV is fully functioning and contains multiple structural elements representative for more complex systems. At the same time, its simplicity enables an in-depth manual analysis. Our analysis shows that cyber-attacks executed against CPS can lead to various cyber-physical interactions. This, in turn, creates novel challenges for CPS defense. Finally, we outline the preliminary results of our work towards a Taxonomy of Cyber-Physical Attacks.
{"title":"Systematic analysis of cyber-attacks on CPS-evaluating applicability of DFD-based approach","authors":"M. Yampolskiy, P. Horváth, X. Koutsoukos, Yuan Xue, J. Sztipanovits","doi":"10.1109/ISRCS.2012.6309293","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309293","url":null,"abstract":"Cyber-Physical Systems (CPSs) consist of as well as interact with cyber and physical elements. This creates multiple vectors for CPS-internal (i.e., within CPS) as well as for CPS-external (i.e., between CPS itself and its environment) Cyber-Physical Attacks. We argue that an effective Cyber-Physical Defense can only be elaborated if possible attacks on CPS can be identified and assessed in a systematic manner. In this paper, we focus on cyber-attacks only. Our contribution in this paper is the following. We assess the applicability of Data Flow Diagrams (DFD) for the systematic analysis of cyber-attacks against CPS. In this context, we introduce several extensions to DFD. We evaluate the analysis procedure by applying it on a comparatively simple example of a quad-rotor UAV. The selected UAV is fully functioning and contains multiple structural elements representative for more complex systems. At the same time, its simplicity enables an in-depth manual analysis. Our analysis shows that cyber-attacks executed against CPS can lead to various cyber-physical interactions. This, in turn, creates novel challenges for CPS defense. Finally, we outline the preliminary results of our work towards a Taxonomy of Cyber-Physical Attacks.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126226964","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309300
S. Thenozhi, Wen Yu, R. Garrido
Accelerometers are one of the most commonly used sensor in structural control and health monitoring applications. However the accelerometer output is polluted with noise and bias signals. Obtaining velocity and position from these acceleration measurements are not trivial. Direct integration will result in an output drift. In this paper baseline correction and filtering techniques are used to overcome these problems. Experimental results on a linear actuator illustrates the effectiveness of the proposed method.
{"title":"A novel numerical integrator for structural health monitoring","authors":"S. Thenozhi, Wen Yu, R. Garrido","doi":"10.1109/ISRCS.2012.6309300","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309300","url":null,"abstract":"Accelerometers are one of the most commonly used sensor in structural control and health monitoring applications. However the accelerometer output is polluted with noise and bias signals. Obtaining velocity and position from these acceleration measurements are not trivial. Direct integration will result in an output drift. In this paper baseline correction and filtering techniques are used to overcome these problems. Experimental results on a linear actuator illustrates the effectiveness of the proposed method.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115263842","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309302
Erik Reed, Abe Ishihara, O. Mengshoel
This paper considers the problem of providing, for computational processes, soft real-time (or reactive) response without the use of a hard real-time operating system. In particular, we focus on the problem of reactively computing fault diagnosis by means of different Bayesian network inference algorithms on non-real-time operating systems where low-criticality (background) process activity and system load is unpredictable. To address this problem, we take in this paper a reconfigurable adaptive control approach. Computation time is modeled using an ARX model where the input consists of the maximum number of background processes allowed to run at any given time. To ensure that the reactive (high-criticality) diagnosis is computed within a set time frame, we introduce a minimum degree pole placement controller to impose a limit on the maximum number of low-criticality processes. Experimentally, we perform electrical power system diagnosis using a Bayesian network model of and data from a NASA electrical power network. The Bayesian network inference algorithms likelihood weighting and junction tree propagation are successfully applied and changed mid-simulation to investigate how inference computation time changes in an unpredictable operating system, as well as how the controller reacts to inference algorithm changes.
{"title":"Adaptive control of Bayesian network computation","authors":"Erik Reed, Abe Ishihara, O. Mengshoel","doi":"10.1109/ISRCS.2012.6309302","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309302","url":null,"abstract":"This paper considers the problem of providing, for computational processes, soft real-time (or reactive) response without the use of a hard real-time operating system. In particular, we focus on the problem of reactively computing fault diagnosis by means of different Bayesian network inference algorithms on non-real-time operating systems where low-criticality (background) process activity and system load is unpredictable. To address this problem, we take in this paper a reconfigurable adaptive control approach. Computation time is modeled using an ARX model where the input consists of the maximum number of background processes allowed to run at any given time. To ensure that the reactive (high-criticality) diagnosis is computed within a set time frame, we introduce a minimum degree pole placement controller to impose a limit on the maximum number of low-criticality processes. Experimentally, we perform electrical power system diagnosis using a Bayesian network model of and data from a NASA electrical power network. The Bayesian network inference algorithms likelihood weighting and junction tree propagation are successfully applied and changed mid-simulation to investigate how inference computation time changes in an unpredictable operating system, as well as how the controller reacts to inference algorithm changes.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130142538","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309294
D. Berman, J. Butts
Industrial control systems (ICS) have an inherent lack of security and situational awareness capabilities at the field device level. Yet these systems comprise a significant portion of the nation's critical infrastructure. Currently, there is little insight into the characterization of attacks on ICS. Stuxnet provided an initial look at the type of tactics that can be employed to create physical damage via cyber means. The question still remains, however, as to the extent of malware and attacks that are targeting the critical infrastructure, along with the various methods employed to target systems associated with the ICS environment. This paper presents a device using Gumstix technology that emulates an ICS field device. The emulation device is low-cost, adaptable to myriad ICS environments and provides logging capabilities at the field device level. The device was evaluated to ensure conformity to RFC standards and that the operating characteristics are consistent with actual field devices.
{"title":"Towards characterization of cyber attacks on industrial control systems: Emulating field devices using Gumstix technology","authors":"D. Berman, J. Butts","doi":"10.1109/ISRCS.2012.6309294","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309294","url":null,"abstract":"Industrial control systems (ICS) have an inherent lack of security and situational awareness capabilities at the field device level. Yet these systems comprise a significant portion of the nation's critical infrastructure. Currently, there is little insight into the characterization of attacks on ICS. Stuxnet provided an initial look at the type of tactics that can be employed to create physical damage via cyber means. The question still remains, however, as to the extent of malware and attacks that are targeting the critical infrastructure, along with the various methods employed to target systems associated with the ICS environment. This paper presents a device using Gumstix technology that emulates an ICS field device. The emulation device is low-cost, adaptable to myriad ICS environments and provides logging capabilities at the field device level. The device was evaluated to ensure conformity to RFC standards and that the operating characteristics are consistent with actual field devices.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133841018","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309291
C. Rieger, Quanyan Zhu, T. Başar
The implementation of automated regulatory control has been around since the middle of the last century through analog means. It has allowed engineers to operate the plant more consistently by focusing on overall operations and settings instead of individual monitoring of local instruments (inside and outside of a control room). A similar approach is proposed for cyber security, where current border-protection designs have been inherited from information technology developments that lack consideration of the high-reliability, high consequence nature of industrial control systems. Instead of an independent development, however, an integrated approach is taken to develop a holistic understanding of performance. This performance takes shape inside a multi-agent design, which provides a notional context to model highly decentralized and complex industrial process control systems, the nervous system of critical infrastructure. The resulting strategy will provide a framework for researching solutions to security and unrecognized interdependency concerns with industrial control systems.
{"title":"Agent-based cyber control strategy design for resilient control systems: Concepts, architecture and methodologies","authors":"C. Rieger, Quanyan Zhu, T. Başar","doi":"10.1109/ISRCS.2012.6309291","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309291","url":null,"abstract":"The implementation of automated regulatory control has been around since the middle of the last century through analog means. It has allowed engineers to operate the plant more consistently by focusing on overall operations and settings instead of individual monitoring of local instruments (inside and outside of a control room). A similar approach is proposed for cyber security, where current border-protection designs have been inherited from information technology developments that lack consideration of the high-reliability, high consequence nature of industrial control systems. Instead of an independent development, however, an integrated approach is taken to develop a holistic understanding of performance. This performance takes shape inside a multi-agent design, which provides a notional context to model highly decentralized and complex industrial process control systems, the nervous system of critical infrastructure. The resulting strategy will provide a framework for researching solutions to security and unrecognized interdependency concerns with industrial control systems.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128631283","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309305
H. Garcia, Wen-Chiao Lin, S. Meerkov, M. Ravichandran
This paper presents a novel data quality model as part of a monitoring system that degrades gracefully under attacks on its sensors. The attacker is assumed to manipulate the sensor data's variance or mean, with the aim of projecting a false state of the plant. Each sensor's data is assigned a level of trust, termed data quality, as part of assessing the states of the process variables. For the variance-based attacker, it is established that the concept of data quality is not, in fact, necessary to obtain the best possible assessment. For the mean-based attacker, it is recognized that statistical means are not sufficient to discern data quality. To combat this problem, the so-called method of probing signals is proposed. The efficacy of this method is illustrated by numerical experiments categorized into two parts. The first deals with individual process variable assessment, while the second deals with the adaptation of the sensor network to obtain the best possible plant assessment.
{"title":"Data quality assessment: Modelling and application in resilient monitoring systems","authors":"H. Garcia, Wen-Chiao Lin, S. Meerkov, M. Ravichandran","doi":"10.1109/ISRCS.2012.6309305","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309305","url":null,"abstract":"This paper presents a novel data quality model as part of a monitoring system that degrades gracefully under attacks on its sensors. The attacker is assumed to manipulate the sensor data's variance or mean, with the aim of projecting a false state of the plant. Each sensor's data is assigned a level of trust, termed data quality, as part of assessing the states of the process variables. For the variance-based attacker, it is established that the concept of data quality is not, in fact, necessary to obtain the best possible assessment. For the mean-based attacker, it is recognized that statistical means are not sufficient to discern data quality. To combat this problem, the so-called method of probing signals is proposed. The efficacy of this method is illustrated by numerical experiments categorized into two parts. The first deals with individual process variable assessment, while the second deals with the adaptation of the sensor network to obtain the best possible plant assessment.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129057508","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309318
S. Kerman, D. Brown, M. Goodrich
In this paper we propose a bio-inspired model for a decentralized swarm of robots, similar to the model proposed by Couzin [5], that allows for dynamic task assignment and is robust to limited communication from a human. We provide evidence that the model has two fundamental attractors: a torus attractor and a flock attractor. Through simulation and mathematical analysis we investigate the stability of these attractors and show that a control input can be used to force the system to change from one attractor to the other. Finally, we generalize another of Couzin's ideas [4] and present the idea of a stakeholder agent. We show how a human operator can use stakeholders to responsively influence group behavior while maintaining group structure.
{"title":"Supporting human interaction with robust robot swarms","authors":"S. Kerman, D. Brown, M. Goodrich","doi":"10.1109/ISRCS.2012.6309318","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309318","url":null,"abstract":"In this paper we propose a bio-inspired model for a decentralized swarm of robots, similar to the model proposed by Couzin [5], that allows for dynamic task assignment and is robust to limited communication from a human. We provide evidence that the model has two fundamental attractors: a torus attractor and a flock attractor. Through simulation and mathematical analysis we investigate the stability of these attractors and show that a control input can be used to force the system to change from one attractor to the other. Finally, we generalize another of Couzin's ideas [4] and present the idea of a stakeholder agent. We show how a human operator can use stakeholders to responsively influence group behavior while maintaining group structure.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115633538","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309306
E. Eyisi, X. Koutsoukos, N. Kottenstette
Uncertainty in wireless networks, such as time-varying delays and packet loss, often leads to instability and degraded performance in Networked Control Systems (NCS). Further, limited network resources impose constraints on communication between plants and controllers. In this paper, we use passivity combined with adaptive sampling to design a control architecture for trajectory tracking. The proposed architecture can tolerate time-varying delays and packet loss while efficiently utilizing network bandwidth. We provide analytical results to show passivity of the proposed networked control architecture and trajectory tracking. We demonstrate our approach using a case study on the trajectory tracking control of a robotic manipulator over a wireless network. The simulation results show the efficient utilization of network resources as well as robustness to network uncertainties.
{"title":"Passivity-based trajectory tracking control with adaptive sampling over a wireless network","authors":"E. Eyisi, X. Koutsoukos, N. Kottenstette","doi":"10.1109/ISRCS.2012.6309306","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309306","url":null,"abstract":"Uncertainty in wireless networks, such as time-varying delays and packet loss, often leads to instability and degraded performance in Networked Control Systems (NCS). Further, limited network resources impose constraints on communication between plants and controllers. In this paper, we use passivity combined with adaptive sampling to design a control architecture for trajectory tracking. The proposed architecture can tolerate time-varying delays and packet loss while efficiently utilizing network bandwidth. We provide analytical results to show passivity of the proposed networked control architecture and trajectory tracking. We demonstrate our approach using a case study on the trajectory tracking control of a robotic manipulator over a wireless network. The simulation results show the efficient utilization of network resources as well as robustness to network uncertainties.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115142973","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 : 2012-09-24DOI: 10.1109/ISRCS.2012.6309307
F. Ferrese, S. Biswas, Q. Dong, Li Bai
This paper presents multi-agent based control of networked linear time invariant systems in a noisy environment. The control protocol is based on output information received from other subsystems through the communication channel, which imparts noise to the sensor data. We show that the sum of the mean square state errors between various subsystems converges to a small bound for the multi-agent system. It is apparent that a higher controller gain tends to make the networked system arrive at a consensus faster, while at the same time has the detrimental effect of enlarging the radius of consensus. Resilience of consensus is demonstrated in that the controller maintains collective stability in the event of communication or subsystem failures.
{"title":"Resiliency of linear system consensus in the presence of channel noise","authors":"F. Ferrese, S. Biswas, Q. Dong, Li Bai","doi":"10.1109/ISRCS.2012.6309307","DOIUrl":"https://doi.org/10.1109/ISRCS.2012.6309307","url":null,"abstract":"This paper presents multi-agent based control of networked linear time invariant systems in a noisy environment. The control protocol is based on output information received from other subsystems through the communication channel, which imparts noise to the sensor data. We show that the sum of the mean square state errors between various subsystems converges to a small bound for the multi-agent system. It is apparent that a higher controller gain tends to make the networked system arrive at a consensus faster, while at the same time has the detrimental effect of enlarging the radius of consensus. Resilience of consensus is demonstrated in that the controller maintains collective stability in the event of communication or subsystem failures.","PeriodicalId":227062,"journal":{"name":"2012 5th International Symposium on Resilient Control Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123557144","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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