Pub Date : 2013-06-09DOI: 10.1109/ICC.2013.6655488
D. Katselis, C. Fischione, H. Hjalmarsson
A major constraint in deployments of resource-limited networks is the energy consumption related to the battery lifetime of the network nodes. To this end, power efficient digital modulation techniques such as On-Off keying (OOK) are highly attractive. In this paper, a novel complete probabilistic description of the Direct Sequence - Coded Division Multiple Access (DS-CDMA) system with random signatures employing OOK modulation is presented. The system scenario considers simultaneously transmitting nodes in Rayleigh fading conditions. Numerical simulations are provided to support the derived results.
{"title":"OOK/DS-CDMA bit error probability over Rayleigh fading channels","authors":"D. Katselis, C. Fischione, H. Hjalmarsson","doi":"10.1109/ICC.2013.6655488","DOIUrl":"https://doi.org/10.1109/ICC.2013.6655488","url":null,"abstract":"A major constraint in deployments of resource-limited networks is the energy consumption related to the battery lifetime of the network nodes. To this end, power efficient digital modulation techniques such as On-Off keying (OOK) are highly attractive. In this paper, a novel complete probabilistic description of the Direct Sequence - Coded Division Multiple Access (DS-CDMA) system with random signatures employing OOK modulation is presented. The system scenario considers simultaneously transmitting nodes in Rayleigh fading conditions. Numerical simulations are provided to support the derived results.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"3 1","pages":"5619-5624"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81890743","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 : 2013-06-09DOI: 10.1109/ICC.2013.6654980
A. Vizziello, S. Kianoush, L. Favalli, P. Gamba
In cognitive radio networks (CRNs), knowledge of the primary users (PUs) position can be used to avoid harmful interference to the primary network, while at the same time be exploited to improve CR performance. In this paper, a localization algorithm is developed to calculate PUs position and a novel location based CR (LCR) routing protocol is proposed that has the following properties: (i) it considers the existence of heterogeneous PUs, (ii) exploits PUs location information, (iii) jointly selects spectrum and route, (iv) protects PUs from interference. Clusters of CRs are defined according to the spectral characteristics in a given location area, and the LCR routing protocol acts in two steps: intra-cluster and inter-cluster. Simulations are conducted in terms of CR end-to-end performance and PUs collision risk. Results reveal the importance of formulating routing protocol in terms of PU protection, which is a unique features in CR networks.
{"title":"Location based routing protocol exploiting heterogeneous primary users in cognitive radio networks","authors":"A. Vizziello, S. Kianoush, L. Favalli, P. Gamba","doi":"10.1109/ICC.2013.6654980","DOIUrl":"https://doi.org/10.1109/ICC.2013.6654980","url":null,"abstract":"In cognitive radio networks (CRNs), knowledge of the primary users (PUs) position can be used to avoid harmful interference to the primary network, while at the same time be exploited to improve CR performance. In this paper, a localization algorithm is developed to calculate PUs position and a novel location based CR (LCR) routing protocol is proposed that has the following properties: (i) it considers the existence of heterogeneous PUs, (ii) exploits PUs location information, (iii) jointly selects spectrum and route, (iv) protects PUs from interference. Clusters of CRs are defined according to the spectral characteristics in a given location area, and the LCR routing protocol acts in two steps: intra-cluster and inter-cluster. Simulations are conducted in terms of CR end-to-end performance and PUs collision risk. Results reveal the importance of formulating routing protocol in terms of PU protection, which is a unique features in CR networks.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"12 1","pages":"2890-2894"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81897242","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 : 2013-06-09DOI: 10.1109/ICC.2013.6654842
Fei Wang, Bin Xiao, Kai Bu, Jinshu Su
Blocker tags are initially introduced to protect regular tags in certain ID ranges, called blocking ranges, from unwanted scanning in RFID systems. But if misused, blocker tags can cause blocking attacks that corrupt the communication between interfered regular tags and readers. Previous approaches can only detect blocking behavior. However, they cannot distinguish malicious blocking from legitimate blocking that can be perfectly allowed to protect customer's privacy. To solve the problem, we carry out the first attempt in the paper to detect real blocking attacks by identifying malicious blocking ranges from authorized ones in a system. We present two pioneer probe-based protocols that can accurately identify malicious blocking ranges in popular tree-based RFID systems, and get rid of their impact before performing RFID applications. We validate the efficacy of the two protocols through theoretical analysis and simulation experiments. The results show that our protocols can identify blocking ranges very fast even when the blocker tag percentage is very low, for example, dozens of blocker tags among tens of thousands of regular tags. Our protocols deliver also a faster blocker tag detection than previous detection methods; our best protocol reduces detection time by over 90% compared with the state-of-the-art detection method.
{"title":"Detect and identify blocker tags in tree-based RFID systems","authors":"Fei Wang, Bin Xiao, Kai Bu, Jinshu Su","doi":"10.1109/ICC.2013.6654842","DOIUrl":"https://doi.org/10.1109/ICC.2013.6654842","url":null,"abstract":"Blocker tags are initially introduced to protect regular tags in certain ID ranges, called blocking ranges, from unwanted scanning in RFID systems. But if misused, blocker tags can cause blocking attacks that corrupt the communication between interfered regular tags and readers. Previous approaches can only detect blocking behavior. However, they cannot distinguish malicious blocking from legitimate blocking that can be perfectly allowed to protect customer's privacy. To solve the problem, we carry out the first attempt in the paper to detect real blocking attacks by identifying malicious blocking ranges from authorized ones in a system. We present two pioneer probe-based protocols that can accurately identify malicious blocking ranges in popular tree-based RFID systems, and get rid of their impact before performing RFID applications. We validate the efficacy of the two protocols through theoretical analysis and simulation experiments. The results show that our protocols can identify blocking ranges very fast even when the blocker tag percentage is very low, for example, dozens of blocker tags among tens of thousands of regular tags. Our protocols deliver also a faster blocker tag detection than previous detection methods; our best protocol reduces detection time by over 90% compared with the state-of-the-art detection method.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"9 1","pages":"2133-2137"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84276446","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 : 2013-06-09DOI: 10.1109/ICC.2013.6654722
I. Al-Anbagi, M. Khanafer, H. Mouftah
Certain Wireless Sensor Network (WSN) applications such as patient monitoring, smart grid, and equipment condition monitoring require accurate estimation of specific WSN parameters such as end-to-end delay, reliability and power consumption. The estimation of these parameters calls for an accurate and lightweight WSN model that is suitable for the low processing capabilities of sensor nodes. In this paper, we present a Markov-based model for WSNs that considers the impact of inserting a MAC-level finite buffer on the performance of WSNs. We perform a comprehensive performance analysis of the end-to-end delay, reliability and power consumption using different traffic and network conditions in star and cluster-tree WSN topologies. Furthermore, we test the accuracy of our model by conducting extensive simulations in environments that are consistent with the analytical model.
{"title":"MAC finite buffer impact on the performance of cluster-tree based WSNs","authors":"I. Al-Anbagi, M. Khanafer, H. Mouftah","doi":"10.1109/ICC.2013.6654722","DOIUrl":"https://doi.org/10.1109/ICC.2013.6654722","url":null,"abstract":"Certain Wireless Sensor Network (WSN) applications such as patient monitoring, smart grid, and equipment condition monitoring require accurate estimation of specific WSN parameters such as end-to-end delay, reliability and power consumption. The estimation of these parameters calls for an accurate and lightweight WSN model that is suitable for the low processing capabilities of sensor nodes. In this paper, we present a Markov-based model for WSNs that considers the impact of inserting a MAC-level finite buffer on the performance of WSNs. We perform a comprehensive performance analysis of the end-to-end delay, reliability and power consumption using different traffic and network conditions in star and cluster-tree WSN topologies. Furthermore, we test the accuracy of our model by conducting extensive simulations in environments that are consistent with the analytical model.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"15 1","pages":"1485-1490"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84317394","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 : 2013-06-09DOI: 10.1109/ICC.2013.6655548
Amiotosh Ghosh, W. Hamouda
We propose algorithms to address the channel allocation and fairness issues of multi band multiuser cognitive ad-hoc networks. Nodes in the network have unequal channel access probability and have no prior information about the offered bandwidth or number of users in the multiple access system. In that nodes use reinforcement learning algorithm to predict future channel selection probability from the past experience and reach an equilibrium state. Proof of convergence of this multi party stochastic game is provided. Furthermore, analytical throughput for such system is determined. Finally, numerical results are presented for performance evaluation of the proposed channel allocation algorithms.
{"title":"Channel selection for heterogeneous nodes in cognitive networks","authors":"Amiotosh Ghosh, W. Hamouda","doi":"10.1109/ICC.2013.6655548","DOIUrl":"https://doi.org/10.1109/ICC.2013.6655548","url":null,"abstract":"We propose algorithms to address the channel allocation and fairness issues of multi band multiuser cognitive ad-hoc networks. Nodes in the network have unequal channel access probability and have no prior information about the offered bandwidth or number of users in the multiple access system. In that nodes use reinforcement learning algorithm to predict future channel selection probability from the past experience and reach an equilibrium state. Proof of convergence of this multi party stochastic game is provided. Furthermore, analytical throughput for such system is determined. Finally, numerical results are presented for performance evaluation of the proposed channel allocation algorithms.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"14 1","pages":"5939-5943"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84357199","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 : 2013-06-09DOI: 10.1109/ICC.2013.6654904
Pål Grønsund, P. Pawełczak, Jihoon Park, D. Cabric
We present results on the system level performance of the IEEE 802.22 standard with sensing functionality, using a highly detailed implementation of the IEEE 802.22 protocol stack in the NS-2 simulator. Our attention is focused on the effect of spatio-temporal wireless microphone (WM) activity on the performance of the IEEE 802.22 network with spectrum sensing considered. In general we find that the frequency of WM appearance and activity duration should be quite high in all channels not used by TV broadcasters to reduce IEEE 802.22 throughput, for example about 50% WM occupancy in each of total of four channels. Impact on WM performance is found to be low in general using the two-stage spectrum sensing strategy with frequent sensing stages.
{"title":"Sensing of wireless microphones in IEEE 802.22: A system level performance evaluation","authors":"Pål Grønsund, P. Pawełczak, Jihoon Park, D. Cabric","doi":"10.1109/ICC.2013.6654904","DOIUrl":"https://doi.org/10.1109/ICC.2013.6654904","url":null,"abstract":"We present results on the system level performance of the IEEE 802.22 standard with sensing functionality, using a highly detailed implementation of the IEEE 802.22 protocol stack in the NS-2 simulator. Our attention is focused on the effect of spatio-temporal wireless microphone (WM) activity on the performance of the IEEE 802.22 network with spectrum sensing considered. In general we find that the frequency of WM appearance and activity duration should be quite high in all channels not used by TV broadcasters to reduce IEEE 802.22 throughput, for example about 50% WM occupancy in each of total of four channels. Impact on WM performance is found to be low in general using the two-stage spectrum sensing strategy with frequent sensing stages.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"35 1","pages":"2475-2479"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84471680","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 : 2013-06-09DOI: 10.1109/ICC.2013.6655436
Mohieddine El Soussi, A. Zaidi, L. Vandendorpe
We study a system in which two sources communicate with a destination with the help of a half-duplex relay. We consider a decoding strategy, based on the compute-and-forward strategy, in which the destination decodes two integer-valued linear combinations that relate the transmitted codewords. In this strategy, the relay compresses its observation using Wyner-Ziv compression and then forwards it to the destination. The destination appropriately combines what it gets from the direct transmission and the relay. Then, using this combination, it computes two integer-valued linear combinations. We discuss the encoding/decoding strategy, and evaluate the achievable sum-rate. Next, we consider the problem of allocating the powers and selecting the integer-valued coefficients of the recovered linear combinations in order to maximize the sum-rate. For the model under consideration, the optimization problem is NP hard. We propose an iterative algorithm to solve this problem using coordinate descent method. The results are illustrated through some numerical examples.
{"title":"Compress-and-forward on a multiaccess relay channel with computation at the receiver","authors":"Mohieddine El Soussi, A. Zaidi, L. Vandendorpe","doi":"10.1109/ICC.2013.6655436","DOIUrl":"https://doi.org/10.1109/ICC.2013.6655436","url":null,"abstract":"We study a system in which two sources communicate with a destination with the help of a half-duplex relay. We consider a decoding strategy, based on the compute-and-forward strategy, in which the destination decodes two integer-valued linear combinations that relate the transmitted codewords. In this strategy, the relay compresses its observation using Wyner-Ziv compression and then forwards it to the destination. The destination appropriately combines what it gets from the direct transmission and the relay. Then, using this combination, it computes two integer-valued linear combinations. We discuss the encoding/decoding strategy, and evaluate the achievable sum-rate. Next, we consider the problem of allocating the powers and selecting the integer-valued coefficients of the recovered linear combinations in order to maximize the sum-rate. For the model under consideration, the optimization problem is NP hard. We propose an iterative algorithm to solve this problem using coordinate descent method. The results are illustrated through some numerical examples.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"146 1","pages":"5339-5344"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84929034","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 : 2013-06-09DOI: 10.1109/ICC.2013.6655324
M. Elgenedy, A. Elezabi
In this paper we introduce a new and simple method to estimate the symbol rate for single carrier systems of unknown modulation. The introduced technique detects the symbol rate from a continuous range of symbol rates, i.e. it does not assume a finite set of candidate symbol rates. The method does not require any knowledge about system parameters and is therefore totally blind. The method belongs to the family of autocorrelation-based symbol rate estimators, yet, unlike many such schemes, its performance is insensitive to the value of the roll-off factor. We then propose a simple method for frequency offset compensation also based on the autocorrelation function. The proposed estimator is implemented as part of a complete DVB-C [1] receiver and is verified using simulations and results in robust performance even at low SNR and high frequency offsets.
{"title":"Blind symbol rate estimation using autocorrelation and zero crossing detection","authors":"M. Elgenedy, A. Elezabi","doi":"10.1109/ICC.2013.6655324","DOIUrl":"https://doi.org/10.1109/ICC.2013.6655324","url":null,"abstract":"In this paper we introduce a new and simple method to estimate the symbol rate for single carrier systems of unknown modulation. The introduced technique detects the symbol rate from a continuous range of symbol rates, i.e. it does not assume a finite set of candidate symbol rates. The method does not require any knowledge about system parameters and is therefore totally blind. The method belongs to the family of autocorrelation-based symbol rate estimators, yet, unlike many such schemes, its performance is insensitive to the value of the roll-off factor. We then propose a simple method for frequency offset compensation also based on the autocorrelation function. The proposed estimator is implemented as part of a complete DVB-C [1] receiver and is verified using simulations and results in robust performance even at low SNR and high frequency offsets.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"1 1","pages":"4750-4755"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85079427","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 : 2013-06-09DOI: 10.1109/ICC.2013.6655428
Hanbae Kong, Changick Song, Haewook Park, Inkyu Lee
In this paper, we propose a new beamforming technique for signal-to-noise ratio maximization in nonregenerative multiple-input multiple-output cooperative relaying systems where a non-negligible direct link between the source and the destination exists. Instead of conventional optimal schemes resorting to an iterative method such as a gradient ascent algorithm, we provide a simple closed form solution for source-relay joint beamformer designs. To this end, we apply the error decomposition property which allows us to separate the problem into two phases. Then, we propose a new beamforming scheme which adaptively aligns the transmit signal to each phase depending on the channel condition. From simulation results, we confirm that the proposed technique obtains the near-optimal performance.
{"title":"Adaptive beamforming designs for MIMO AF relaying systems with direct link","authors":"Hanbae Kong, Changick Song, Haewook Park, Inkyu Lee","doi":"10.1109/ICC.2013.6655428","DOIUrl":"https://doi.org/10.1109/ICC.2013.6655428","url":null,"abstract":"In this paper, we propose a new beamforming technique for signal-to-noise ratio maximization in nonregenerative multiple-input multiple-output cooperative relaying systems where a non-negligible direct link between the source and the destination exists. Instead of conventional optimal schemes resorting to an iterative method such as a gradient ascent algorithm, we provide a simple closed form solution for source-relay joint beamformer designs. To this end, we apply the error decomposition property which allows us to separate the problem into two phases. Then, we propose a new beamforming scheme which adaptively aligns the transmit signal to each phase depending on the channel condition. From simulation results, we confirm that the proposed technique obtains the near-optimal performance.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"10 1","pages":"5296-5300"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85144040","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 : 2013-06-09DOI: 10.1109/ICC.2013.6655544
S. Huang, R. Cheng
A two-way relay (TWR) channel is considered where two users exchange their messages with the help of a single relay. With the assumption of separate relay power budget and user power budget, we maximize the sum-rate of the TWR channel using physical-layer network coding (PNC) with flexible time fraction. We propose an optimal power allocation scheme between users and find that in high signal-to-noise ratio (SNR) regime, the user power should be allocated inversely proportional to the channel gains. Moreover, the bidirectional streams of the PNC-TWR enjoy full diversity gain. The analysis of the equal time fraction case and the numerical results of the flexible time fraction case both imply that the PNC relaying performs better than the decode-and-forward based TWR (DF-TWR) if the channel gains are similar, while the DF relaying performs better if the channel gains are quite different.
{"title":"Resource allocation for two-way relaying with network coding","authors":"S. Huang, R. Cheng","doi":"10.1109/ICC.2013.6655544","DOIUrl":"https://doi.org/10.1109/ICC.2013.6655544","url":null,"abstract":"A two-way relay (TWR) channel is considered where two users exchange their messages with the help of a single relay. With the assumption of separate relay power budget and user power budget, we maximize the sum-rate of the TWR channel using physical-layer network coding (PNC) with flexible time fraction. We propose an optimal power allocation scheme between users and find that in high signal-to-noise ratio (SNR) regime, the user power should be allocated inversely proportional to the channel gains. Moreover, the bidirectional streams of the PNC-TWR enjoy full diversity gain. The analysis of the equal time fraction case and the numerical results of the flexible time fraction case both imply that the PNC relaying performs better than the decode-and-forward based TWR (DF-TWR) if the channel gains are similar, while the DF relaying performs better if the channel gains are quite different.","PeriodicalId":6368,"journal":{"name":"2013 IEEE International Conference on Communications (ICC)","volume":"95 1","pages":"5919-5923"},"PeriodicalIF":0.0,"publicationDate":"2013-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85727199","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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