Pub Date : 2013-11-14DOI: 10.1109/IWMN.2013.6663768
A. Berger, Albert Pötsch, A. Springer
In industrial applications of wireless sensor networks (WSNs) synchronized sampling of data on each sensor node is often required. Thus the wireless communication protocol needs to support accurate timing synchronization. If due to a high sampling rate also high data throughput is required, WSNs based on the IEEE 802.15.4 physical layer often do not provide sufficient data rate. Wireless communication based on the well established IEEE 802.11 (WLAN) standard provides high data throughput but not an accurate timing synchronization unless the protocol stack is severely changed. We propose a hybrid WSN which uses WLAN for high rate data transmission combined with a proprietary wireless communication system operating on Sub-GHz short range devices for synchronization. A consensus-based synchronization algorithm is used to be independent from the number of WSN nodes and node failure. The proposed hybrid WSN performs a two-step synchronization algorithm which can easily be executed on an 8-bit microcontroller and achieves a sampling jitter smaller than 50 μs.
{"title":"Synchronized industrial wireless sensor network with IEEE 802.11 ad hoc data transmission","authors":"A. Berger, Albert Pötsch, A. Springer","doi":"10.1109/IWMN.2013.6663768","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663768","url":null,"abstract":"In industrial applications of wireless sensor networks (WSNs) synchronized sampling of data on each sensor node is often required. Thus the wireless communication protocol needs to support accurate timing synchronization. If due to a high sampling rate also high data throughput is required, WSNs based on the IEEE 802.15.4 physical layer often do not provide sufficient data rate. Wireless communication based on the well established IEEE 802.11 (WLAN) standard provides high data throughput but not an accurate timing synchronization unless the protocol stack is severely changed. We propose a hybrid WSN which uses WLAN for high rate data transmission combined with a proprietary wireless communication system operating on Sub-GHz short range devices for synchronization. A consensus-based synchronization algorithm is used to be independent from the number of WSN nodes and node failure. The proposed hybrid WSN performs a two-step synchronization algorithm which can easily be executed on an 8-bit microcontroller and achieves a sampling jitter smaller than 50 μs.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"188 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":"133753277","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.2013.6663773
B. Andò, S. Baglio, A. Pistorio, G. Marco Tina, C. Ventura
Monitoring a PV plant has a remarkable impact on its efficiency. In this context, Wireless Sensor Networks (WSNs) can be a low cost, but reliable solution to perform the real-time monitoring task. The main objective of this work is the realization of a WSN that allows to monitor at panel level the efficiency of Photovoltaic (PV) panels, to provide data useful to investigate on causes of efficiency losses and to detect inertial events possibly related to attempts of theft or tampering but also to mechanical striking events. Nodes of the WSN, which are installed on each PV module, are equipped with voltage, current, irradiance, temperature and inertial sensors. Acquired data are then transferred to a management center which is in charge of estimating efficiency losses and correlated causes, tampering and inertial events at the level of the single module. In particular, this paper is focused on a solution for the automatic estimation of efficiency losses of a PV module and related causes.
{"title":"SENTINELLA: A WSN for a smart monitoring of PV systems at module level","authors":"B. Andò, S. Baglio, A. Pistorio, G. Marco Tina, C. Ventura","doi":"10.1109/IWMN.2013.6663773","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663773","url":null,"abstract":"Monitoring a PV plant has a remarkable impact on its efficiency. In this context, Wireless Sensor Networks (WSNs) can be a low cost, but reliable solution to perform the real-time monitoring task. The main objective of this work is the realization of a WSN that allows to monitor at panel level the efficiency of Photovoltaic (PV) panels, to provide data useful to investigate on causes of efficiency losses and to detect inertial events possibly related to attempts of theft or tampering but also to mechanical striking events. Nodes of the WSN, which are installed on each PV module, are equipped with voltage, current, irradiance, temperature and inertial sensors. Acquired data are then transferred to a management center which is in charge of estimating efficiency losses and correlated causes, tampering and inertial events at the level of the single module. In particular, this paper is focused on a solution for the automatic estimation of efficiency losses of a PV module and related causes.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"18 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":"130145970","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.2013.6663782
Francesco Marino, G. Massei, L. Paura
The proliferation of the RFID (Radio-Frequency IDentification) technology in the last decade shows its importance as effective solution for a large variety of applications. Actually, an accurate RFID modeling and the associated performance analysis via simulation is strongly desired. In this paper, the authors present the modeling and performance simulation of EPC Gen 2 RFID on OPNET Modeler, a popular, comprehensive and industry's leading network modeling and simulation platform. Thanks to these accurate reader and tag models is possible to accurately analyze the tag collision problem, to quickly evaluate the performance in both static and dynamic application scenarios, as well as to justify some technical configurations. Moreover, such models represent a fundamental tool for the development of innovative tag anti-collision algorithms.
近十年来，射频识别技术(RFID)的发展表明，它作为一种有效的解决方案，在各种各样的应用中发挥着重要作用。实际上，通过仿真进行准确的RFID建模和相关的性能分析是非常必要的。本文采用OPNET Modeler这一业界领先的网络建模与仿真平台，对EPC Gen 2 RFID进行了建模与性能仿真。由于这些准确的阅读器和标签模型，可以准确地分析标签碰撞问题，快速评估静态和动态应用场景下的性能，以及证明一些技术配置。此外，这些模型代表了创新标签防碰撞算法发展的基本工具。
{"title":"Modeling and performance simulation of EPC Gen2 RFID on OPNET","authors":"Francesco Marino, G. Massei, L. Paura","doi":"10.1109/IWMN.2013.6663782","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663782","url":null,"abstract":"The proliferation of the RFID (Radio-Frequency IDentification) technology in the last decade shows its importance as effective solution for a large variety of applications. Actually, an accurate RFID modeling and the associated performance analysis via simulation is strongly desired. In this paper, the authors present the modeling and performance simulation of EPC Gen 2 RFID on OPNET Modeler, a popular, comprehensive and industry's leading network modeling and simulation platform. Thanks to these accurate reader and tag models is possible to accurately analyze the tag collision problem, to quickly evaluate the performance in both static and dynamic application scenarios, as well as to justify some technical configurations. Moreover, such models represent a fundamental tool for the development of innovative tag anti-collision algorithms.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"106 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":"123725456","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.2013.6663801
I. Neri, Riccardo Centonze, M. L. Fravolini, A. Moschitta
Indoor positioning using RF signals is usually a difficult task, due to multipath phenomena, that, especially for narrowband transmissions, can deeply affect signal propagation. In this paper, a simple technique for improving the accuracy of a received signal strength based ranging system is proposed. It is shown that, using narrowband low power transmissions in the 2.4 GHz channel and a multiple input multiple output approach, multipath effects can be mitigated, leading to a significant improvement in accuracy.
{"title":"A simple ranging technique based on received signal strength measurements in a narrowband 2.4 GHz channel: A space diversity approach","authors":"I. Neri, Riccardo Centonze, M. L. Fravolini, A. Moschitta","doi":"10.1109/IWMN.2013.6663801","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663801","url":null,"abstract":"Indoor positioning using RF signals is usually a difficult task, due to multipath phenomena, that, especially for narrowband transmissions, can deeply affect signal propagation. In this paper, a simple technique for improving the accuracy of a received signal strength based ranging system is proposed. It is shown that, using narrowband low power transmissions in the 2.4 GHz channel and a multiple input multiple output approach, multipath effects can be mitigated, leading to a significant improvement in accuracy.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"13 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":"129183843","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.2013.6663786
D. F. Hermida, C. López-Bravo, F. González-Castaño, V. Estévez-David, M. Rodelgo-Lacruz
The growth of Internet traffic and the many different traffic classes that exist make network performance control extremely difficult for operators. The methods available rely on complex or costly hardware. However, recent research on bandwidth sharing has introduced methods that require only basic statistics of aggregated link utilization, such as mean and variance. This data can be easily obtained through SNMP calls, lowering the cost of monitoring systems. Unfortunately, to the best of our knowledge, no tools have yet been developed to implement these methods. This paper presents the implementation of a plugin for the monitoring environment Nagios and the validation of a degradation detection tool from link utilization traces. The plugin does not require complex or costly hardware for acquiring data. Instead, it employs basic SNMP data about link utilization.
{"title":"Practical early detection of performance degradation in aggregated traffic links","authors":"D. F. Hermida, C. López-Bravo, F. González-Castaño, V. Estévez-David, M. Rodelgo-Lacruz","doi":"10.1109/IWMN.2013.6663786","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663786","url":null,"abstract":"The growth of Internet traffic and the many different traffic classes that exist make network performance control extremely difficult for operators. The methods available rely on complex or costly hardware. However, recent research on bandwidth sharing has introduced methods that require only basic statistics of aggregated link utilization, such as mean and variance. This data can be easily obtained through SNMP calls, lowering the cost of monitoring systems. Unfortunately, to the best of our knowledge, no tools have yet been developed to implement these methods. This paper presents the implementation of a plugin for the monitoring environment Nagios and the validation of a degradation detection tool from link utilization traces. The plugin does not require complex or costly hardware for acquiring data. Instead, it employs basic SNMP data about link utilization.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"75 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":"120929681","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.2013.6663774
A. Lay-Ekuakille, P. Vergallo, G. Griffo, O. Kanoun, F. Angelillo, A. Trabacca
Wireless network architecture allows the implementation of fatigue measurement that was once performed in a limited and constrained way due to the use of wired connections. This paper presents measurement acquisitions by means of wireless network that allows joint acquisition of electroencephalograms, electrocardiograms and ergospirometry signals. This opportunity permits to a person walking to a dedicated path (about 30 meters) to develop fatigue that is recorded in function of EEG and ECG. Only wireless configuration allows the patient under test to walk. Some issues have been developed to detect interesting features on transmitted signals for epilepsy detection.
{"title":"Wireless network acquisition of joint EEG-ECG-ergospirometric signals for epilepsy detection","authors":"A. Lay-Ekuakille, P. Vergallo, G. Griffo, O. Kanoun, F. Angelillo, A. Trabacca","doi":"10.1109/IWMN.2013.6663774","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663774","url":null,"abstract":"Wireless network architecture allows the implementation of fatigue measurement that was once performed in a limited and constrained way due to the use of wired connections. This paper presents measurement acquisitions by means of wireless network that allows joint acquisition of electroencephalograms, electrocardiograms and ergospirometry signals. This opportunity permits to a person walking to a dedicated path (about 30 meters) to develop fatigue that is recorded in function of EEG and ECG. Only wireless configuration allows the patient under test to walk. Some issues have been developed to detect interesting features on transmitted signals for epilepsy detection.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"1 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":"134119158","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.2013.6663770
G. Giorgi, C. Narduzzi
The problem of device synchronization in a distributed measuring system can present a designer with a range of choices and solutions, depending on technical specifications, cost, feasibility, robustness and other requirements. In wireless sensor networks (WSNs), synchronization mechanisms often have to be run on lean resources and, in particular, the active and “sleep” time schedules of low-power nodes introduce specific constraints which impact, for instance, on the rate of exchange of timing messages. Loss of timing packets could also be particularly critical. In this paper we analyse how clock instability, timestamp uncertainty and the particular implementation of a servo clock affect the performances of a synchronization algorithm, assuming relevant information are received at a low rate (and, occasionally, missing). An accurate study based on the effect of measurement uncertainty will evaluate the performance of a low-power synchronization mechanism and its robustness to information loss.
{"title":"Some notes on the synchronization of low-power wireless nodes","authors":"G. Giorgi, C. Narduzzi","doi":"10.1109/IWMN.2013.6663770","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663770","url":null,"abstract":"The problem of device synchronization in a distributed measuring system can present a designer with a range of choices and solutions, depending on technical specifications, cost, feasibility, robustness and other requirements. In wireless sensor networks (WSNs), synchronization mechanisms often have to be run on lean resources and, in particular, the active and “sleep” time schedules of low-power nodes introduce specific constraints which impact, for instance, on the rate of exchange of timing messages. Loss of timing packets could also be particularly critical. In this paper we analyse how clock instability, timestamp uncertainty and the particular implementation of a servo clock affect the performances of a synchronization algorithm, assuming relevant information are received at a low rate (and, occasionally, missing). An accurate study based on the effect of measurement uncertainty will evaluate the performance of a low-power synchronization mechanism and its robustness to information loss.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"1 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":"132621811","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.2013.6663780
L. Angrisani, A. Botta, G. Miele, M. Vadursi
The paper is the first step towards the goal of evaluating the measurement uncertainty of the inter-departure times (IDT) provided by software traffic generator. The paper is focused on the experimental characterization of the internal generation cycle of a well-known, open source generator, namely D-ITG, for different systems, and under the best possible conditions, i.e. with the minimum system loads. The resulting performance may be seen as the ideal limit the generator can tend to. The extended abstract presents the rationale for the activity, the underlying methodology and some initial tests that highlight the relevance of the clock resolution in the accuracy of IDT.
{"title":"An experimental characterization of the internal generation cycle of an open-source software traffic generator","authors":"L. Angrisani, A. Botta, G. Miele, M. Vadursi","doi":"10.1109/IWMN.2013.6663780","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663780","url":null,"abstract":"The paper is the first step towards the goal of evaluating the measurement uncertainty of the inter-departure times (IDT) provided by software traffic generator. The paper is focused on the experimental characterization of the internal generation cycle of a well-known, open source generator, namely D-ITG, for different systems, and under the best possible conditions, i.e. with the minimum system loads. The resulting performance may be seen as the ideal limit the generator can tend to. The extended abstract presents the rationale for the activity, the underlying methodology and some initial tests that highlight the relevance of the clock resolution in the accuracy of IDT.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"55 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":"131444981","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.2013.6663790
Miquel Martínez, D. Andrés, J. Ruiz, Jesus Friginal
Dependability benchmarking has become through the years more and more important in the process of systems evaluation. The increasing need for making systems more dependable in presence of perturbations has contributed to this fact. Nevertheless, even though many studies have focused on different areas related to dependability benchmarking, and some others have focused on the need of providing these benchmarks with good quality measures, there is still a gap in the process of the analysis of results. This paper focuses on providing a first glance at different approaches that may help filling this gap by making explicit the criteria followed in the decision making process.
{"title":"Analysis of results in dependability benchmarking: Can we do better?","authors":"Miquel Martínez, D. Andrés, J. Ruiz, Jesus Friginal","doi":"10.1109/IWMN.2013.6663790","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663790","url":null,"abstract":"Dependability benchmarking has become through the years more and more important in the process of systems evaluation. The increasing need for making systems more dependable in presence of perturbations has contributed to this fact. Nevertheless, even though many studies have focused on different areas related to dependability benchmarking, and some others have focused on the need of providing these benchmarks with good quality measures, there is still a gap in the process of the analysis of results. This paper focuses on providing a first glance at different approaches that may help filling this gap by making explicit the criteria followed in the decision making process.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"249 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":"132367466","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.2013.6663799
L. Paura, Roberto Savoia
In this paper, the impact of the sensing accuracy on the transmission capacity achievable by the cognitive user (CU) is studied in a mobile primary-user (PU) network scenario. To this aim, first of all, the spatial-temporal spectrum sensing model is extended to account for the PU mobility effects that influence the number of discovered spatial opportunities. Then, a new performance metric for Cognitive Radio networks, referred to as mobility-aware sensing enabled capacity, is introduced. It measures the actual transmission capacity achievable by the CU in a mobile PU network scenario with a realistic sensing detection capability, namely in the presence of imperfect sensing decisions. The performance assessment highlights the impact of the sensing accuracy on the channel access probability; in particular, it reveals the existence of an optimal sensing time value that maximizes the mobility-aware sensing enabled capacity, which depends on sensing and mobility parameters.
{"title":"Mobility-aware sensing enabled capacity in Cognitive Radio networks","authors":"L. Paura, Roberto Savoia","doi":"10.1109/IWMN.2013.6663799","DOIUrl":"https://doi.org/10.1109/IWMN.2013.6663799","url":null,"abstract":"In this paper, the impact of the sensing accuracy on the transmission capacity achievable by the cognitive user (CU) is studied in a mobile primary-user (PU) network scenario. To this aim, first of all, the spatial-temporal spectrum sensing model is extended to account for the PU mobility effects that influence the number of discovered spatial opportunities. Then, a new performance metric for Cognitive Radio networks, referred to as mobility-aware sensing enabled capacity, is introduced. It measures the actual transmission capacity achievable by the CU in a mobile PU network scenario with a realistic sensing detection capability, namely in the presence of imperfect sensing decisions. The performance assessment highlights the impact of the sensing accuracy on the channel access probability; in particular, it reveals the existence of an optimal sensing time value that maximizes the mobility-aware sensing enabled capacity, which depends on sensing and mobility parameters.","PeriodicalId":218660,"journal":{"name":"2013 IEEE International Workshop on Measurements & Networking (M&N)","volume":"26 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":"115400482","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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