In this paper, considering hidden terminal and exposed node problems, we make a theoretical analysis on the performance of commonly used energy detection methods, such as ideal method, transmitter-independent method and transmitter/receiver-cooperated method, in terms of detection probability. Corresponding analytical models are provided. Performance theoretical curves are acquired to compare the characteristics for individual energy detection methods under various scenarios. Moreover the upper bound for detection probability is achieved and is compared under various system traffic intensity and sensing capability.
{"title":"Performance Analysis of Energy Detection for Cognitive RadioWireless Networks","authors":"Qingchun Ren, Q. Liang","doi":"10.1109/WASA.2007.80","DOIUrl":"https://doi.org/10.1109/WASA.2007.80","url":null,"abstract":"In this paper, considering hidden terminal and exposed node problems, we make a theoretical analysis on the performance of commonly used energy detection methods, such as ideal method, transmitter-independent method and transmitter/receiver-cooperated method, in terms of detection probability. Corresponding analytical models are provided. Performance theoretical curves are acquired to compare the characteristics for individual energy detection methods under various scenarios. Moreover the upper bound for detection probability is achieved and is compared under various system traffic intensity and sensing capability.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115994030","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}
J. Hemmes, D. Thain, C. Poellabauer, C. Moretti, P. Snowberger, B. McNutt
Much research in mobile networks relies on the use of simulations for evaluation purposes. While a number of powerful simulation tools have been developed for this purpose, only recently has the need for physical implementations of mobile systems and applications been widely accepted in the literature. In recognition of this need, and to further our research objectives in the area of wireless sensor networks and mobile cooperative systems, we have built the TeamTrak mobile testbed, which gives us real-world experience with research concepts as we develop them. Additionally, results from outdoor field tests are used to further enhance the capabilities of the testbed itself.
{"title":"Lessons Learned Building TeamTrak: An Urban/Outdoor Mobile Testbed","authors":"J. Hemmes, D. Thain, C. Poellabauer, C. Moretti, P. Snowberger, B. McNutt","doi":"10.1109/WASA.2007.117","DOIUrl":"https://doi.org/10.1109/WASA.2007.117","url":null,"abstract":"Much research in mobile networks relies on the use of simulations for evaluation purposes. While a number of powerful simulation tools have been developed for this purpose, only recently has the need for physical implementations of mobile systems and applications been widely accepted in the literature. In recognition of this need, and to further our research objectives in the area of wireless sensor networks and mobile cooperative systems, we have built the TeamTrak mobile testbed, which gives us real-world experience with research concepts as we develop them. Additionally, results from outdoor field tests are used to further enhance the capabilities of the testbed itself.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126913518","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}
In this paper, we present singular-value decomposition- QR with threshold (SVD-QR-T) algorithm to select a subset of channels in virtual MIMO wireless sensor networks (WSN) in order to reduce its complexity and cost. SVD- QR-T selects best subset of transmitters while keeping all receivers active. The threshold is adaptive by means of fuzzy c-mean (FCM). Under the constraint of the same total transmission power, this approach is compared against the case without channel selection in terms of capacity, bit error rate (BER) and multiplexing gain in the presence of water-filling as well without. It is shown that in spite of less multiplexing gain, when water-filling is applied, SVD- QR-T FCM provides lower BER at moderate to high SNR; in case of equal transmission power allocation, SVD-QR-T FCM achieves higher capacity at low SNR and lower BER. In general, it provides satisfying performances compared to the case without channel selection but reduced cost and resource.
{"title":"SVD-QR-T FCM Approach for Virtual MIMO Channel Selection in Wireless Sensor Networks","authors":"Jinghan Liang, Q. Liang","doi":"10.1109/WASA.2007.131","DOIUrl":"https://doi.org/10.1109/WASA.2007.131","url":null,"abstract":"In this paper, we present singular-value decomposition- QR with threshold (SVD-QR-T) algorithm to select a subset of channels in virtual MIMO wireless sensor networks (WSN) in order to reduce its complexity and cost. SVD- QR-T selects best subset of transmitters while keeping all receivers active. The threshold is adaptive by means of fuzzy c-mean (FCM). Under the constraint of the same total transmission power, this approach is compared against the case without channel selection in terms of capacity, bit error rate (BER) and multiplexing gain in the presence of water-filling as well without. It is shown that in spite of less multiplexing gain, when water-filling is applied, SVD- QR-T FCM provides lower BER at moderate to high SNR; in case of equal transmission power allocation, SVD-QR-T FCM achieves higher capacity at low SNR and lower BER. In general, it provides satisfying performances compared to the case without channel selection but reduced cost and resource.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130942973","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}
Wireless mesh networks have gained significant academic and industry attentions in the recent years. Supporting quality of service in wireless mesh networks is an important and challenging task which involves both medium access control and network layer design. In this paper, we investigate the problem of end-to-end on-demand bandwidth allocation in infrastructure wireless mesh networks. We formulate it as a combinatorial optimization problem, and prove that it is NP- hard. We present a polynomial time 2-approximation algorithm, MCRS (minimum consumption routing and scheduling), based on the concepts of consumption level for routing and bottom set for scheduling. Comprehensive simulation results show that MCRS achieves better performance than traditional methods based on minimum hop routing.
{"title":"A Cross-Layer Design for End-to-End On-Demand Bandwidth Allocation in Infrastructure Wireless Mesh Network","authors":"Hong Lu, S. Liu, Anxiao Jiang","doi":"10.1109/WASA.2007.133","DOIUrl":"https://doi.org/10.1109/WASA.2007.133","url":null,"abstract":"Wireless mesh networks have gained significant academic and industry attentions in the recent years. Supporting quality of service in wireless mesh networks is an important and challenging task which involves both medium access control and network layer design. In this paper, we investigate the problem of end-to-end on-demand bandwidth allocation in infrastructure wireless mesh networks. We formulate it as a combinatorial optimization problem, and prove that it is NP- hard. We present a polynomial time 2-approximation algorithm, MCRS (minimum consumption routing and scheduling), based on the concepts of consumption level for routing and bottom set for scheduling. Comprehensive simulation results show that MCRS achieves better performance than traditional methods based on minimum hop routing.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133350697","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}
Considering three dimensional time hopping ultra wide band (TH-UWB) sensor networks with n sensor nodes uniformly and independently distributed in a cube of unit volume, the asymptotic lower bounds on the lifetime of non-cluster-based and cluster-based three dimensional TH-UWB sensor networks are derived irrespectively. For static three dimensional TH-UWB sensor networks, our finding is that the lower bound on the lifetime of cluster-based network is Omega((n/log n)alpha/3) and that the lower bound on the lifetime of non-cluster-based network is Omega((n/log n)(alpha-3)/3), thus clustering can significantly improve the lower bound on network lifetime. The results also indicate that for non-cluster-based three dimensional TH-UWB sensor network the lower bound on the lifetime in idea case is longer than that of static network by a factor of (n/log n)2/3, thus sensor nodes or sink moving randomly in the sensor field can improve the lower bound on lifetime of network.
{"title":"Lower Bounds on Lifetime of Three Dimensional UWB Sensor Networks","authors":"Juan Xu, Yongfa Hong, Changjun Jiang","doi":"10.1109/WASA.2007.30","DOIUrl":"https://doi.org/10.1109/WASA.2007.30","url":null,"abstract":"Considering three dimensional time hopping ultra wide band (TH-UWB) sensor networks with n sensor nodes uniformly and independently distributed in a cube of unit volume, the asymptotic lower bounds on the lifetime of non-cluster-based and cluster-based three dimensional TH-UWB sensor networks are derived irrespectively. For static three dimensional TH-UWB sensor networks, our finding is that the lower bound on the lifetime of cluster-based network is Omega((n/log n)alpha/3) and that the lower bound on the lifetime of non-cluster-based network is Omega((n/log n)(alpha-3)/3), thus clustering can significantly improve the lower bound on network lifetime. The results also indicate that for non-cluster-based three dimensional TH-UWB sensor network the lower bound on the lifetime in idea case is longer than that of static network by a factor of (n/log n)2/3, thus sensor nodes or sink moving randomly in the sensor field can improve the lower bound on lifetime of network.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115847275","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}
The security problem in multihop wireless networks is more severe than that in wired networks since its transmission media is the unprotected air. In this paper, we show how to increase the effective throughput via carefully choosing the multi-path routing for given source and destination nodes, where we call the total packets from the mesh routers to the gateway nodes that are not attacked by an attacker as effective throughput. We assume that the attacker has limited resources for attacking while attacking a node or a link will incur some certain cost. We show that it is NP-hard to find an optimum routing policy even if the attacking strategy is given. We model the problem as a two-player game between the routing policy designer and the attacker and propose a multi-path routing protocol for several possible attacks. We propose several routing protocols that can approximately maximize the total throughput achieved by the gateway nodes. Moreover, we theoretically prove that our routing protocols can achieve an effective network throughput (with packets which are not attacked) within a constant factor of the optimum in the worst case. Our theoretic results are confirmed by extensive simulations studies.
{"title":"Stochastic Security in Wireless Mesh Networks via Saddle Routing Policy","authors":"Xiangyang Li, Yanwei Wu, Weizhao Wang","doi":"10.1109/WASA.2007.86","DOIUrl":"https://doi.org/10.1109/WASA.2007.86","url":null,"abstract":"The security problem in multihop wireless networks is more severe than that in wired networks since its transmission media is the unprotected air. In this paper, we show how to increase the effective throughput via carefully choosing the multi-path routing for given source and destination nodes, where we call the total packets from the mesh routers to the gateway nodes that are not attacked by an attacker as effective throughput. We assume that the attacker has limited resources for attacking while attacking a node or a link will incur some certain cost. We show that it is NP-hard to find an optimum routing policy even if the attacking strategy is given. We model the problem as a two-player game between the routing policy designer and the attacker and propose a multi-path routing protocol for several possible attacks. We propose several routing protocols that can approximately maximize the total throughput achieved by the gateway nodes. Moreover, we theoretically prove that our routing protocols can achieve an effective network throughput (with packets which are not attacked) within a constant factor of the optimum in the worst case. Our theoretic results are confirmed by extensive simulations studies.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126039260","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}
Relay transmissions improve performance and save communication energy in wireless network. We present an optimal relay nodes assignment algorithm to maximize the number of information packets received at the sink for a two-tiered wireless network, in which the relay nodes are temporarily placed and have energy constraint. We first derive the optimal transmit power theory from relay node to sink node. Provided the limited energy at the relay nodes, we prove that the total transmission periods or the relay network lifetime is fixed. Subsequently, we determine the optimal dynamic association between edge nodes and relay nodes (multiple-to-one mapping) using binary integer programming (BIP). Experimental results show that the proposed method has significantly better performance than two other schemes in terms of the total number of information packets received at the sink. Combined with the optimal relay transmit power technique, the two-tiered wireless network can achieve the highest capacity considering the energy constraint of relay nodes.
{"title":"Relaying Packets in a Two-tiered Wireless Network Using Binary Integer Programming","authors":"Wenxuan Guo, Xinming Huang","doi":"10.1109/WASA.2007.39","DOIUrl":"https://doi.org/10.1109/WASA.2007.39","url":null,"abstract":"Relay transmissions improve performance and save communication energy in wireless network. We present an optimal relay nodes assignment algorithm to maximize the number of information packets received at the sink for a two-tiered wireless network, in which the relay nodes are temporarily placed and have energy constraint. We first derive the optimal transmit power theory from relay node to sink node. Provided the limited energy at the relay nodes, we prove that the total transmission periods or the relay network lifetime is fixed. Subsequently, we determine the optimal dynamic association between edge nodes and relay nodes (multiple-to-one mapping) using binary integer programming (BIP). Experimental results show that the proposed method has significantly better performance than two other schemes in terms of the total number of information packets received at the sink. Combined with the optimal relay transmit power technique, the two-tiered wireless network can achieve the highest capacity considering the energy constraint of relay nodes.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124480631","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}
Given the extremely limited hardware resources on sensor nodes and the inclement deploying environment, the adversary denial-of-service (DoS) attack becomes a serious security threat toward wireless sensor networks. Without adequate defense mechanism, the adversary can simply inundate the network by flooding the bogus data packets, and paralyze the partial or whole sensor network by depleting node battery power. Prior work on false packet filtering in sensor networks are mostly based on symmetric key schemes, with the concern that the public key operations are too expensive for the resource constrained sensors. Recent progress in public key implementations on sensors, however, has shown that public key is already feasible for sensors. In this paper, we present PDF, a Public-key based false data filtering scheme that leverages Shamir's threshold cryptography and elliptic curve cryptography (ECC), and effectively rejects 100% of false data packets. We evaluate PDF by real world implementation on MICAz motes. Our experiment results support the conclusion that PDF is practical for real world sensor deployment.
{"title":"PDF: A Public-key based False Data Filtering Scheme in Sensor Networks","authors":"Haodong Wang, Qun A. Li","doi":"10.1109/WASA.2007.35","DOIUrl":"https://doi.org/10.1109/WASA.2007.35","url":null,"abstract":"Given the extremely limited hardware resources on sensor nodes and the inclement deploying environment, the adversary denial-of-service (DoS) attack becomes a serious security threat toward wireless sensor networks. Without adequate defense mechanism, the adversary can simply inundate the network by flooding the bogus data packets, and paralyze the partial or whole sensor network by depleting node battery power. Prior work on false packet filtering in sensor networks are mostly based on symmetric key schemes, with the concern that the public key operations are too expensive for the resource constrained sensors. Recent progress in public key implementations on sensors, however, has shown that public key is already feasible for sensors. In this paper, we present PDF, a Public-key based false data filtering scheme that leverages Shamir's threshold cryptography and elliptic curve cryptography (ECC), and effectively rejects 100% of false data packets. We evaluate PDF by real world implementation on MICAz motes. Our experiment results support the conclusion that PDF is practical for real world sensor deployment.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121059507","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}
Radio frequency identification (RFID) is a promising technology for automated non-line-of-sight object identification. However, factors such as object occlusions, metal/liquid opaqueness, environmental conditions, and radio noise degrade the overall availability, reliability, and dependability of RFID systems. We show that simply increasing the number of readers does not adequately address these issues. Instead, we propose tagging each object with multiple tags, and provide definitive experimental data showing that this strategy dramatically improves the effectiveness of RFID systems in the face of radio noise and other interfering factors. We solidify the case for multi-tag RFID systems by addressing obstacles to reliable object detection, and analyzing how multi-tags improve tag detection, even in the presence of (radio-opaque) metals and liquids. We discuss applications that will benefit considerably from multi-tags, and propose careful RFID system design through the deployment of appropriate types of multi-tags and anti-collision algorithms. We also analyze the economics of multi-tag RFID systems and argue that the benefits of multi-tags can substantially outweigh the costs in many current applications, and that this trend will become even more pronounced in the future.
{"title":"The Case for Multi-Tag RFID Systems","authors":"L. Bolotnyy, G. Robins","doi":"10.1109/WASA.2007.44","DOIUrl":"https://doi.org/10.1109/WASA.2007.44","url":null,"abstract":"Radio frequency identification (RFID) is a promising technology for automated non-line-of-sight object identification. However, factors such as object occlusions, metal/liquid opaqueness, environmental conditions, and radio noise degrade the overall availability, reliability, and dependability of RFID systems. We show that simply increasing the number of readers does not adequately address these issues. Instead, we propose tagging each object with multiple tags, and provide definitive experimental data showing that this strategy dramatically improves the effectiveness of RFID systems in the face of radio noise and other interfering factors. We solidify the case for multi-tag RFID systems by addressing obstacles to reliable object detection, and analyzing how multi-tags improve tag detection, even in the presence of (radio-opaque) metals and liquids. We discuss applications that will benefit considerably from multi-tags, and propose careful RFID system design through the deployment of appropriate types of multi-tags and anti-collision algorithms. We also analyze the economics of multi-tag RFID systems and argue that the benefits of multi-tags can substantially outweigh the costs in many current applications, and that this trend will become even more pronounced in the future.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"234 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126030060","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}
Deploying wireless sensor networks has been recognized as one of the effective and cost-efficient ways to defend remote barrier regions such as international territorial borders. It has also been demonstrated recently that, by introducing sensor mobility into the wireless sensor network, the network coverage performance can be greatly improved. In this paper, we employ a game theoretic approach to study the problem of defending against barrier intrusions with mobile sensors, and demonstrate the equilibriums between barrier intrusions and sensor movement strategies in both non-obstructed and obstructed barriers. In particular, we derive the optimal sensor movement strategy to defend non-obstructed barriers, and propose a Dijkstra-like algorithm to generate a sensor movement strategy that performs well in defending obstructed barriers. We verify the correctness of our theoretic analysis by conducting in-depth simulations under various barrier intrusion and sensor movement scenarios.
{"title":"Defending Against Barrier Intrusions with Mobile Sensors","authors":"Guanqun Yang, W. Zhou, D. Qiao","doi":"10.1109/WASA.2007.149","DOIUrl":"https://doi.org/10.1109/WASA.2007.149","url":null,"abstract":"Deploying wireless sensor networks has been recognized as one of the effective and cost-efficient ways to defend remote barrier regions such as international territorial borders. It has also been demonstrated recently that, by introducing sensor mobility into the wireless sensor network, the network coverage performance can be greatly improved. In this paper, we employ a game theoretic approach to study the problem of defending against barrier intrusions with mobile sensors, and demonstrate the equilibriums between barrier intrusions and sensor movement strategies in both non-obstructed and obstructed barriers. In particular, we derive the optimal sensor movement strategy to defend non-obstructed barriers, and propose a Dijkstra-like algorithm to generate a sensor movement strategy that performs well in defending obstructed barriers. We verify the correctness of our theoretic analysis by conducting in-depth simulations under various barrier intrusion and sensor movement scenarios.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124600678","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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