Pub Date : 2013-11-14DOI: 10.1109/IWMN.2013.6663804
B. Andò, S. Baglio, C. O. Lombardo, V. Marletta, E. Pergolizzi, A. Pistorio
This paper deals with the RESIMA architecture developed to assist people in performing daily activity in indoor environment. As respect to solutions presented in the SOTA, RESIMA is a smart multi-parametric assistive system which performs a high resolution monitoring of the user position in the spatial-temporal domain as well as a deep inertial monitoring of the user status, thus assuring a reliable and continuous form of assistance to weak users. The system is based on a Wireless Sensor Network and smart paradigms which extract relevant information from data collected through the multi-sensor architecture. The paper mainly focuses on the multi-sensor system architecture and smart paradigms used to implement user localization. Positioning system accuracy of about 3 cm has been obtained while the system shows good reproducibility and reliability.
{"title":"RESIMA: A new WSN based paradigm to assist weak people in indoor environment","authors":"B. Andò, S. Baglio, C. O. Lombardo, V. Marletta, E. Pergolizzi, A. Pistorio","doi":"10.1109/IWMN.2013.6663804","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663804","url":null,"abstract":"This paper deals with the RESIMA architecture developed to assist people in performing daily activity in indoor environment. As respect to solutions presented in the SOTA, RESIMA is a smart multi-parametric assistive system which performs a high resolution monitoring of the user position in the spatial-temporal domain as well as a deep inertial monitoring of the user status, thus assuring a reliable and continuous form of assistance to weak users. The system is based on a Wireless Sensor Network and smart paradigms which extract relevant information from data collected through the multi-sensor architecture. The paper mainly focuses on the multi-sensor system architecture and smart paradigms used to implement user localization. Positioning system accuracy of about 3 cm has been obtained while the system shows good reproducibility and reliability.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124338082","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 : 2013-11-14DOI: 10.1109/IWMN.2013.6663797
Piotr Rygielski, Samuel Kounev, S. Zschaler
In this paper, we address the problem of performance analysis in computer networks. We present a new meta-model designed for the performance modeling of network infrastructures in modern data centers. Instances of our metamodel can be automatically transformed into stochastic simulation models for performance prediction. We evaluate the approach in a case study of a road traffic monitoring system. We compare the performance prediction results against the real system and a benchmark. The presented results show that our approach, despite of introducing many modeling abstractions, delivers predictions with errors less than 32% and correctly detects bottlenecks in the modeled network.
{"title":"Model-based throughput prediction in data center networks","authors":"Piotr Rygielski, Samuel Kounev, S. Zschaler","doi":"10.1109/IWMN.2013.6663797","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663797","url":null,"abstract":"In this paper, we address the problem of performance analysis in computer networks. We present a new meta-model designed for the performance modeling of network infrastructures in modern data centers. Instances of our metamodel can be automatically transformed into stochastic simulation models for performance prediction. We evaluate the approach in a case study of a road traffic monitoring system. We compare the performance prediction results against the real system and a benchmark. The presented results show that our approach, despite of introducing many modeling abstractions, delivers predictions with errors less than 32% and correctly detects bottlenecks in the modeled network.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125093435","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 : 2013-11-14DOI: 10.1109/IWMN.2013.6663806
Samuele Gasparrini, E. Gambi, S. Spinsante
This paper evaluates the use of the wireless ANT protocol as a possible technology to implement a heart monitoring solution for the remote management of patients at their home premises.With respect to common commercial solutions, in which the ANT transceiver transmits single heart rate values, this paper investigates the suitability of the protocol for the transmission of complete ECG traces, which could be a useful feature in the framework of a remote health monitoring solution. Further, a frequency agility capability is also implemented, in order to reduce the impact of RF interferers working in the ISM band, and to improve the ECG transmission performance of the ANT device.
{"title":"Evaluation and possible improvements of the ANT protocol for home heart monitoring applications","authors":"Samuele Gasparrini, E. Gambi, S. Spinsante","doi":"10.1109/IWMN.2013.6663806","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663806","url":null,"abstract":"This paper evaluates the use of the wireless ANT protocol as a possible technology to implement a heart monitoring solution for the remote management of patients at their home premises.With respect to common commercial solutions, in which the ANT transceiver transmits single heart rate values, this paper investigates the suitability of the protocol for the transmission of complete ECG traces, which could be a useful feature in the framework of a remote health monitoring solution. Further, a frequency agility capability is also implemented, in order to reduce the impact of RF interferers working in the ISM band, and to improve the ECG transmission performance of the ANT device.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114348557","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 : 2013-11-14DOI: 10.1109/IWMN.2013.6663802
A. Mariscotti, A. Marrese, N. Pasquino, R. S. L. Moriello
The paper investigates the intra-car propagation properties of the radio channel at 2.45 GHz aboard trains. Results show that path loss is slightly smaller than that in free space and that it does not change significantly with the propagation direction. The delay spread strongly depends on polarization. Finally, the model that best fits the dependence of the coherence bandwidth on delay spread is obtained. The final aim of the presented study is to use such model to evaluate the maximum distance between access points mounted aboard that results in a delay spread that still allows transmission of the bandwidth required for optimal performance of the wifi service.
{"title":"Characterization of the radio propagation channel aboard trains for optimal coverage at 2.45GHz","authors":"A. Mariscotti, A. Marrese, N. Pasquino, R. S. L. Moriello","doi":"10.1109/IWMN.2013.6663802","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663802","url":null,"abstract":"The paper investigates the intra-car propagation properties of the radio channel at 2.45 GHz aboard trains. Results show that path loss is slightly smaller than that in free space and that it does not change significantly with the propagation direction. The delay spread strongly depends on polarization. Finally, the model that best fits the dependence of the coherence bandwidth on delay spread is obtained. The final aim of the presented study is to use such model to evaluate the maximum distance between access points mounted aboard that results in a delay spread that still allows transmission of the bandwidth required for optimal performance of the wifi service.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132165259","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 : 2013-11-14DOI: 10.1109/IWMN.2013.6663776
A. Platonov, I. Zaitsev
The paper concerns the challenges of optimization of physical (PHY) layer of wireless sensor networks (WSN). It is shown that performance of communication links of PHY layer can be considerably improved by transition to analog transmission in the channels “sensor node - base station” (SNBS). Unlike digital one, analog transmission allows optimization of communication links using tools of Bayesian estimation theory. The results of optimization determine minimal mean square error, limit power-bandwidth efficiency of transmission, capacity of the link and analytical form of transmission-reception algorithm permitting SNBS to attain these boundaries. The latter one permits to design high quality low energy/size/cost SNBS links for WSN with star and cluster topology.
{"title":"Performance of PHY layer links of WSN: Criterions and ways of improvement","authors":"A. Platonov, I. Zaitsev","doi":"10.1109/IWMN.2013.6663776","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663776","url":null,"abstract":"The paper concerns the challenges of optimization of physical (PHY) layer of wireless sensor networks (WSN). It is shown that performance of communication links of PHY layer can be considerably improved by transition to analog transmission in the channels “sensor node - base station” (SNBS). Unlike digital one, analog transmission allows optimization of communication links using tools of Bayesian estimation theory. The results of optimization determine minimal mean square error, limit power-bandwidth efficiency of transmission, capacity of the link and analytical form of transmission-reception algorithm permitting SNBS to attain these boundaries. The latter one permits to design high quality low energy/size/cost SNBS links for WSN with star and cluster topology.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134287605","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 : 2013-11-14DOI: 10.1109/IWMN.2013.6663777
G. Vakulya, G. Simon
In this paper a low-power communication protocol is proposed for sensor networks, where sensors mostly send measurements and rarely receive commands. The proposed protocol optimizes energy utilization on sensor nodes by using a modified MAC-layer, with acknowledgment frames piggy-backing meta-information towards sensor nodes. The proposed method is evaluated using real measurements using a modified protocol stack of IEEE 802.15.4.
{"title":"Low-power communication protocol for low duty cycle data acquisition applications","authors":"G. Vakulya, G. Simon","doi":"10.1109/IWMN.2013.6663777","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663777","url":null,"abstract":"In this paper a low-power communication protocol is proposed for sensor networks, where sensors mostly send measurements and rarely receive commands. The proposed protocol optimizes energy utilization on sensor nodes by using a modified MAC-layer, with acknowledgment frames piggy-backing meta-information towards sensor nodes. The proposed method is evaluated using real measurements using a modified protocol stack of IEEE 802.15.4.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"2016 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114571375","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 : 2013-11-14DOI: 10.1109/IWMN.2013.6663800
L. Angrisani, Guido D'Alessandro, M. D'Apuzzo, M. D’Arco
The main issues concerning the development of induction and wireless power transmission technologies aimed at supplying and/or controlling remote electrical equipment are discussed. The attention is mainly paid to critical logistic scenarios and measurement applications. Typical critical logistic scenarios consist in situations in which battery-less instrumentation needs to operate in wastelands or desert zones where connections to the grid are unreliable or missing, or in blocks or buildings where the main grid has been intentionally shut down. Induction and wireless power transmission technologies share large part of the aforementioned field of application. The paper shows the state-of-art of the two technologies and highlights both differences and similarities as well as weak-points and advantages of both of them. Future pilot experiments aimed at enforcing the two technologies are envisaged.
{"title":"Enabling induction and wireless power transmission technologies aimed at supplying remote equipment in critical logistic scenarios","authors":"L. Angrisani, Guido D'Alessandro, M. D'Apuzzo, M. D’Arco","doi":"10.1109/IWMN.2013.6663800","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663800","url":null,"abstract":"The main issues concerning the development of induction and wireless power transmission technologies aimed at supplying and/or controlling remote electrical equipment are discussed. The attention is mainly paid to critical logistic scenarios and measurement applications. Typical critical logistic scenarios consist in situations in which battery-less instrumentation needs to operate in wastelands or desert zones where connections to the grid are unreliable or missing, or in blocks or buildings where the main grid has been intentionally shut down. Induction and wireless power transmission technologies share large part of the aforementioned field of application. The paper shows the state-of-art of the two technologies and highlights both differences and similarities as well as weak-points and advantages of both of them. Future pilot experiments aimed at enforcing the two technologies are envisaged.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120894428","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 : 2013-11-14DOI: 10.1109/IWMN.2013.6663792
A. Bondavalli, F. Brancati, A. Ceccarelli, Diego Santoro, M. Vadursi
Complex and real time systems often operate under variable and non-stationary conditions, thus requiring efficient and extensive monitoring and error detection solutions. Amongst the many, we focus on anomaly detection techniques, which require measuring the evolution of the monitored indicators through time to identify anomalies i.e., deviations from the expected operational behavior. In this paper, we investigate the possibility to model the evolution of indicators through time using the random walk model. In particular, we focus on the detection of system anomalies at the application level (software errors), based on the monitoring of indicators at the Operating System level. The approach is based on the experimental evaluation of a large set of heterogeneous indicators, acquired under different operating conditions, both in terms of workload and fault load, on an air traffic management target system. The results of the analysis show that for a large number of cases, the histogram of the first order time differences well approximates a Gaussian distribution, independently of the nature of the indicator and its statistical distribution. Such outcomes suggest that the idea of adopting a Gaussian random walk model for several monitoring indicators has an experimental support and deserves be further investigated on a wider scale, in order to determine its range of applicability and representativeness.
{"title":"Experimental analysis of the first order time difference of indicators used in the monitoring of complex systems","authors":"A. Bondavalli, F. Brancati, A. Ceccarelli, Diego Santoro, M. Vadursi","doi":"10.1109/IWMN.2013.6663792","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663792","url":null,"abstract":"Complex and real time systems often operate under variable and non-stationary conditions, thus requiring efficient and extensive monitoring and error detection solutions. Amongst the many, we focus on anomaly detection techniques, which require measuring the evolution of the monitored indicators through time to identify anomalies i.e., deviations from the expected operational behavior. In this paper, we investigate the possibility to model the evolution of indicators through time using the random walk model. In particular, we focus on the detection of system anomalies at the application level (software errors), based on the monitoring of indicators at the Operating System level. The approach is based on the experimental evaluation of a large set of heterogeneous indicators, acquired under different operating conditions, both in terms of workload and fault load, on an air traffic management target system. The results of the analysis show that for a large number of cases, the histogram of the first order time differences well approximates a Gaussian distribution, independently of the nature of the indicator and its statistical distribution. Such outcomes suggest that the idea of adopting a Gaussian random walk model for several monitoring indicators has an experimental support and deserves be further investigated on a wider scale, in order to determine its range of applicability and representativeness.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121348280","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 : 2013-10-01DOI: 10.1109/IWMN.2013.6663793
Hiroki Nakayama, S. Ata, I. Oka
It is important to analyze and predict the time series of traffic trends from the perspective of network operation and management, such as that in fine-grained traffic control, capacity dimensioning, and traffic engineering. However, it is difficult to accurately predict traffic trends because this strongly depends on the time, the type of content, and its popularity. We propose new methods of accurately predicting traffic trends in this paper. Our methods are based on a wavelet transform and the auto regressive integrated moving average (ARIMA) model. We first demonstrate that applying a wavelet transform can improve the accuracy of prediction compared to the original ARIMA model; however, it still has large error due to the fixed time granularity of each resolution. We therefore propose a resolution adaptive ARIMA (RA-ARIMA) model to improve accuracy by changing the time granularity according to the degree of resolution. We demonstrate that by applying it to the real monitored data in a major P2P file-sharing system the normalized mean squared error of RA-ARIMA can be reduced by more than 20% of that of Wavelet-ARIMA. Moreover, we also compared RA-ARIMA with other existing models to prove the accuracy of our proposed method.
{"title":"Predicting time series of individual trends with resolution adaptive ARIMA","authors":"Hiroki Nakayama, S. Ata, I. Oka","doi":"10.1109/IWMN.2013.6663793","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663793","url":null,"abstract":"It is important to analyze and predict the time series of traffic trends from the perspective of network operation and management, such as that in fine-grained traffic control, capacity dimensioning, and traffic engineering. However, it is difficult to accurately predict traffic trends because this strongly depends on the time, the type of content, and its popularity. We propose new methods of accurately predicting traffic trends in this paper. Our methods are based on a wavelet transform and the auto regressive integrated moving average (ARIMA) model. We first demonstrate that applying a wavelet transform can improve the accuracy of prediction compared to the original ARIMA model; however, it still has large error due to the fixed time granularity of each resolution. We therefore propose a resolution adaptive ARIMA (RA-ARIMA) model to improve accuracy by changing the time granularity according to the degree of resolution. We demonstrate that by applying it to the real monitored data in a major P2P file-sharing system the normalized mean squared error of RA-ARIMA can be reduced by more than 20% of that of Wavelet-ARIMA. Moreover, we also compared RA-ARIMA with other existing models to prove the accuracy of our proposed method.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122035419","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 : 2013-10-01DOI: 10.1109/IWMN.2013.6663784
D. Darsena, G. Gelli, Fulvio Melito, F. Verde, Andrea Vitiello
This paper considers a multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) wireless network contaminated by Middleton Class A impulsive noise, which is one of the major sources of performance degradation in many wireless systems, including sensor networks. In this scenario, the conventional linear zero-forcing (ZF) equalizer does not perform satisfactorily, since the diversity order does not monotonically increase with the signal-to-noise ratio (SNR). In order to overcome such a problem, we synthesize an improved linear ZF equalizer, which mitigates, in the minimum mean output-energy (MMOE) sense, the impulse noise contribution at the equalizer output. Specifically, the proposed equalizer exploits the fact that the noise samples can be spatially correlated in compact multi-antenna receivers, i.e., when the antenna elements cannot be sufficiently spaced apart due to size constraints. Numerical simulations are performed, aimed at comparing the performances of the proposed ZF-MMOE equalizer with those of competing approaches.
{"title":"Impulse noise mitigation for MIMO-OFDM wireless networks with linear equalization","authors":"D. Darsena, G. Gelli, Fulvio Melito, F. Verde, Andrea Vitiello","doi":"10.1109/IWMN.2013.6663784","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663784","url":null,"abstract":"This paper considers a multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) wireless network contaminated by Middleton Class A impulsive noise, which is one of the major sources of performance degradation in many wireless systems, including sensor networks. In this scenario, the conventional linear zero-forcing (ZF) equalizer does not perform satisfactorily, since the diversity order does not monotonically increase with the signal-to-noise ratio (SNR). In order to overcome such a problem, we synthesize an improved linear ZF equalizer, which mitigates, in the minimum mean output-energy (MMOE) sense, the impulse noise contribution at the equalizer output. Specifically, the proposed equalizer exploits the fact that the noise samples can be spatially correlated in compact multi-antenna receivers, i.e., when the antenna elements cannot be sufficiently spaced apart due to size constraints. Numerical simulations are performed, aimed at comparing the performances of the proposed ZF-MMOE equalizer with those of competing approaches.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131193763","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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