Pub Date : 2010-11-11DOI: 10.1109/WCSP.2010.5633082
Gao Xiangchuan, Fei Xiong, Lei Song
Spatial multiplexing in the multi-user MIMO (MU-MIMO) downlink allows each user in the system to receive multiple data subchannels simultaneously using the same time and spectral resources. In this paper, we have proposed a successive iterative optimization method based on signal-to-leakage-and-noise-ratio (SLNR) maximization algorithm proposed recently, which has no strict constraint on transmit and receive antennas numbers. Accoding to the simulation results, the proposed method outperforms the original SLNR algorithm and have a considerable improvement in BER performance and system capacity.
{"title":"A successive iterative optimization precoding method for downlink multi-user MIMO system","authors":"Gao Xiangchuan, Fei Xiong, Lei Song","doi":"10.1109/WCSP.2010.5633082","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633082","url":null,"abstract":"Spatial multiplexing in the multi-user MIMO (MU-MIMO) downlink allows each user in the system to receive multiple data subchannels simultaneously using the same time and spectral resources. In this paper, we have proposed a successive iterative optimization method based on signal-to-leakage-and-noise-ratio (SLNR) maximization algorithm proposed recently, which has no strict constraint on transmit and receive antennas numbers. Accoding to the simulation results, the proposed method outperforms the original SLNR algorithm and have a considerable improvement in BER performance and system capacity.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"91 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126270996","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5633518
Jun Zhang, Bin Jiang, Shi Jin, Xiqi Gao
This paper investigates the downlink transmission for cooperative cellular networks with multi-base stations and single mobile station using statistical channel state information at the base stations. We consider a general jointly correlated MIMO channel model. We first propose an optimal transmission scheme to maximize the ergodic sum capacity, which reveals the transmit signals of all base stations are mutual independent and the optimal signaling directions are the eigenvectors of the transmit correlation matrix of the MIMO channel. Then we employ the matrix permanents to derive a closed-form tight upper bound for the ergodic sum capacity. Based on these results, we develop a low-complexity power allocation solution using convex optimization techniques and a simple iterative water-filling algorithm. Simulations demonstrate the upper bound of ergodic sum capacity is tight and the cooperative base stations transmission schemes increase the downlink system sum capacity.
{"title":"Multi-base station cooperation downlink statistical eigenmode transmission","authors":"Jun Zhang, Bin Jiang, Shi Jin, Xiqi Gao","doi":"10.1109/WCSP.2010.5633518","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633518","url":null,"abstract":"This paper investigates the downlink transmission for cooperative cellular networks with multi-base stations and single mobile station using statistical channel state information at the base stations. We consider a general jointly correlated MIMO channel model. We first propose an optimal transmission scheme to maximize the ergodic sum capacity, which reveals the transmit signals of all base stations are mutual independent and the optimal signaling directions are the eigenvectors of the transmit correlation matrix of the MIMO channel. Then we employ the matrix permanents to derive a closed-form tight upper bound for the ergodic sum capacity. Based on these results, we develop a low-complexity power allocation solution using convex optimization techniques and a simple iterative water-filling algorithm. Simulations demonstrate the upper bound of ergodic sum capacity is tight and the cooperative base stations transmission schemes increase the downlink system sum capacity.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126335706","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5633790
Z. Cui, Xiuchang Zhu
This paper presents a simple but effective macroblock (MB) layer rate control (RC) scheme for H.264/AVC with low complexity. First, to reduce computation cost and inaccuracy of linear mean absolute difference (MAD) prediction at MB layer adopted in JVT-G012, MAD is computed directly according to the difference between current original MB and the reference blocks pointed by estimated MV using intensive motion similarity. Then, MB header bits are predicted based on spatial-temporal correlation because it is not constant due to complicated coding modes and high compression efficiency of H.264. Finally, MB target bit rate is allocated according to its complexity and the parameters of quadratic R-D model are updated using coded MBs with high spatial-temporal correlation and motion similarity not the last coded data points. Simulation results show that the proposed scheme achieves an average PSNR gain of 0.37 dB, meets better with target bit rate, produces more consistent quality for the MBs in a frame and thus improves visual quality compared to classic JVT-H017 RC algorithm, simultaneously has lower computation complexity and suits for real-time application.
{"title":"A low complexity MB layer rate control algorithm based on motion similarity for H.264","authors":"Z. Cui, Xiuchang Zhu","doi":"10.1109/WCSP.2010.5633790","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633790","url":null,"abstract":"This paper presents a simple but effective macroblock (MB) layer rate control (RC) scheme for H.264/AVC with low complexity. First, to reduce computation cost and inaccuracy of linear mean absolute difference (MAD) prediction at MB layer adopted in JVT-G012, MAD is computed directly according to the difference between current original MB and the reference blocks pointed by estimated MV using intensive motion similarity. Then, MB header bits are predicted based on spatial-temporal correlation because it is not constant due to complicated coding modes and high compression efficiency of H.264. Finally, MB target bit rate is allocated according to its complexity and the parameters of quadratic R-D model are updated using coded MBs with high spatial-temporal correlation and motion similarity not the last coded data points. Simulation results show that the proposed scheme achieves an average PSNR gain of 0.37 dB, meets better with target bit rate, produces more consistent quality for the MBs in a frame and thus improves visual quality compared to classic JVT-H017 RC algorithm, simultaneously has lower computation complexity and suits for real-time application.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126361914","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5630681
Wei Wu, Xin Jia, Yueming Cai, Xiaoxue Wu
Based on the matrix formulation of cooperative-OFDM signals, the bayesian CRB(BCRB) for blind, semi-blind and non-blind channel estimation in cooperative-OFDM system was derived. The BCRB for semi-blind channel estimation was a generic expression, which could be extrapolated to the BCRB for blind and non-blind channel estimation. The effect of the priori information on BCRB was also discussed. We simulated the performance of the channel estimation. In the simulations, we validate the correctness of the BCRB and evaluate some bayesian channel estimation methods using the BCRB.
{"title":"Bayesian Cramér-rao Bound for channel estimation in cooperative OFDM","authors":"Wei Wu, Xin Jia, Yueming Cai, Xiaoxue Wu","doi":"10.1109/WCSP.2010.5630681","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5630681","url":null,"abstract":"Based on the matrix formulation of cooperative-OFDM signals, the bayesian CRB(BCRB) for blind, semi-blind and non-blind channel estimation in cooperative-OFDM system was derived. The BCRB for semi-blind channel estimation was a generic expression, which could be extrapolated to the BCRB for blind and non-blind channel estimation. The effect of the priori information on BCRB was also discussed. We simulated the performance of the channel estimation. In the simulations, we validate the correctness of the BCRB and evaluate some bayesian channel estimation methods using the BCRB.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130093532","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5633478
Xueyun He, Rong-fang Song
The frequency selective channel estimation problem in orthogonal frequency division multiplexing (OFDM) systems is investigated using compressed sensing (CS). Based on minimizing mutual coherence of the measurement matrix in CS theory, a criterion of optimizing the pilot pattern for the CS-based channel estimation is proposed. Simulation results show that using the pilot pattern designed according to the proposed optimization criterion gives a much better performance than using other pilot patterns in terms of the mean square error of the channel estimate as well as the bit error rate of the system.
{"title":"Pilot pattern optimization for compressed sensing based sparse channel estimation in OFDM systems","authors":"Xueyun He, Rong-fang Song","doi":"10.1109/WCSP.2010.5633478","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633478","url":null,"abstract":"The frequency selective channel estimation problem in orthogonal frequency division multiplexing (OFDM) systems is investigated using compressed sensing (CS). Based on minimizing mutual coherence of the measurement matrix in CS theory, a criterion of optimizing the pilot pattern for the CS-based channel estimation is proposed. Simulation results show that using the pilot pattern designed according to the proposed optimization criterion gives a much better performance than using other pilot patterns in terms of the mean square error of the channel estimate as well as the bit error rate of the system.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"273 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131515699","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5633498
Su Xiao
As a stochastic method, the Bayesian estimation demonstrates some advantages on image denoising, such as with image noises treated as random signals. In this paper, we propose a two-stage Bayesian framework for color image denoising, utilizing the joint prior and Gamma distributions, to model the unknowns. All unknowns are estimated and updated simultaneously using evidence analysis within the Bayesian framework. We also propose an optimal luminance/color-difference space projection for the two-stage Bayesian framework, exploiting strong correlation in high-frequency contents of different color components to improve denoising performance. Experimental results confirm that the proposed algorithm offers superior denoising performance compared with existing solutions, both from peak signal-to-noise ratio and visual quality perspectives. By comparing experimentally the performances of the proposed algorithm in different color spaces, we have proven the effectiveness of space projection in improving the image denoising.
{"title":"Bayesian color image denoising via a joint model and space projection","authors":"Su Xiao","doi":"10.1109/WCSP.2010.5633498","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633498","url":null,"abstract":"As a stochastic method, the Bayesian estimation demonstrates some advantages on image denoising, such as with image noises treated as random signals. In this paper, we propose a two-stage Bayesian framework for color image denoising, utilizing the joint prior and Gamma distributions, to model the unknowns. All unknowns are estimated and updated simultaneously using evidence analysis within the Bayesian framework. We also propose an optimal luminance/color-difference space projection for the two-stage Bayesian framework, exploiting strong correlation in high-frequency contents of different color components to improve denoising performance. Experimental results confirm that the proposed algorithm offers superior denoising performance compared with existing solutions, both from peak signal-to-noise ratio and visual quality perspectives. By comparing experimentally the performances of the proposed algorithm in different color spaces, we have proven the effectiveness of space projection in improving the image denoising.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131536101","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5633079
Milan Simek, D. Komosny, Patrik Moravek
Understanding the energy consumption of individual tasks in wireless sensor networks (WSN) is an important aspect for a network deployment. The fundamental task of WSNs is to gather data in the long-term manner. All additive processes such as routing and localization should not significantly affect the life time of the WSN. It was already proved that concurrent anchor free localization algorithms have great localization accuracy but also suffer from the high communication cost. We have performed a detailed analysis of a well-known AFL (Anchor-Free Localization) algorithm to show its excessive energy dissipation. We have proposed a novel BRL (Boundary Recognition aided localization) that significantly optimizes a communication cost of the selection of the reference nodes which are used for subsequent nodes localization. The main idea of the algorithm is to successfully identify the nodes lying on the boundary. Only these nodes subsequently cooperate in the reference nodes selection process and thus decrease the energy load of the network.
{"title":"Establishment of reference localization system based on boundary recognition of wireless sensor network","authors":"Milan Simek, D. Komosny, Patrik Moravek","doi":"10.1109/WCSP.2010.5633079","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633079","url":null,"abstract":"Understanding the energy consumption of individual tasks in wireless sensor networks (WSN) is an important aspect for a network deployment. The fundamental task of WSNs is to gather data in the long-term manner. All additive processes such as routing and localization should not significantly affect the life time of the WSN. It was already proved that concurrent anchor free localization algorithms have great localization accuracy but also suffer from the high communication cost. We have performed a detailed analysis of a well-known AFL (Anchor-Free Localization) algorithm to show its excessive energy dissipation. We have proposed a novel BRL (Boundary Recognition aided localization) that significantly optimizes a communication cost of the selection of the reference nodes which are used for subsequent nodes localization. The main idea of the algorithm is to successfully identify the nodes lying on the boundary. Only these nodes subsequently cooperate in the reference nodes selection process and thus decrease the energy load of the network.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133482643","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5633529
Fang-ming Zhao, J. Hang, Di He
In this paper, channel allocation scheme is studied for overlay wireless networks to optimize connection-level QoS. The contributions of our work are threefold. First, channel allocation scheme using both horizontal channel borrowing and vertical channel borrowing is presented and analyzed. Channel borrowing is restricted within handoff requests, and only predefined channels can be lent. When all the channels in a given cell are used, handoff requests can borrow channels from adjacent homogeneous cells. In case that the horizontal borrowing requests fail, handoff requests may also borrow channels from heterogeneous cells, if possible. Second, to further improve the system performance, other priority strategies such as channel reservation are introduced. And third, to meet the high QoS requirements of some services and increase the utilization of radio resources, certain services can be transformed between real-time services and non-real-time services as necessary. Simulation results demonstrate that the proposed schemes can improve system performance.
{"title":"Channel borrowing based channel allocation scheme and performance analysis for wireless overlay networks","authors":"Fang-ming Zhao, J. Hang, Di He","doi":"10.1109/WCSP.2010.5633529","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633529","url":null,"abstract":"In this paper, channel allocation scheme is studied for overlay wireless networks to optimize connection-level QoS. The contributions of our work are threefold. First, channel allocation scheme using both horizontal channel borrowing and vertical channel borrowing is presented and analyzed. Channel borrowing is restricted within handoff requests, and only predefined channels can be lent. When all the channels in a given cell are used, handoff requests can borrow channels from adjacent homogeneous cells. In case that the horizontal borrowing requests fail, handoff requests may also borrow channels from heterogeneous cells, if possible. Second, to further improve the system performance, other priority strategies such as channel reservation are introduced. And third, to meet the high QoS requirements of some services and increase the utilization of radio resources, certain services can be transformed between real-time services and non-real-time services as necessary. Simulation results demonstrate that the proposed schemes can improve system performance.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131635651","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5633449
Jiandong Li, Chungang Yang
Due to the lack of learning and adaptation abilities in traditional game models, e.g., the strategic Nash game, they can't describe the dynamic behaviors and strategy interactive selections well in the cognitive context. The Markov game theoretical modeling approach is investigated to deal with the power control in the cognitive radio (CR) context, which well captures the learning and adaptation abilities of CRs. With the complex interaction relationship of multiple secondary users (SUs), multiple primary users (PUs) with wireless coexistent environment into consideration, both the secondary overall utility maximization and fairness among the SUs are considered from the mathematical model formulation and the algorithm design perspective. A power control approach to searching for the fair and optimal Nash equilibrium solution (NES) based on the improved multi-agent Q-learning is proposed. Meanwhile, the parameters of the presented algorithm are analyzed through simulations. The numerical results confirm that the proposed algorithm can improve the system utility and also guarantee the fairness among the SUs well.
{"title":"A Markovian game-theoretical power control approach in cognitive radio networks: A multi-agent learning perspective","authors":"Jiandong Li, Chungang Yang","doi":"10.1109/WCSP.2010.5633449","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5633449","url":null,"abstract":"Due to the lack of learning and adaptation abilities in traditional game models, e.g., the strategic Nash game, they can't describe the dynamic behaviors and strategy interactive selections well in the cognitive context. The Markov game theoretical modeling approach is investigated to deal with the power control in the cognitive radio (CR) context, which well captures the learning and adaptation abilities of CRs. With the complex interaction relationship of multiple secondary users (SUs), multiple primary users (PUs) with wireless coexistent environment into consideration, both the secondary overall utility maximization and fairness among the SUs are considered from the mathematical model formulation and the algorithm design perspective. A power control approach to searching for the fair and optimal Nash equilibrium solution (NES) based on the improved multi-agent Q-learning is proposed. Meanwhile, the parameters of the presented algorithm are analyzed through simulations. The numerical results confirm that the proposed algorithm can improve the system utility and also guarantee the fairness among the SUs well.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133817145","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 : 2010-11-11DOI: 10.1109/WCSP.2010.5632008
J. Dai, D. Guo, Bangning Zhang
An iterative decoding scheme with diversity is proposed for LDPC coded FFH/MFSK system under partial-band interference. The performance gain is obtained by soft-information exchange between demodulator and decoder. Extrinsic information transfer (EXIT) chart is employed to study the iterative procedure, which indicates that the convergence speed of the system is fast. The simulation results show the presented scheme outperforms traditional FFH/BFSK system, and the gain increases as the jamming probability increases. In addition, a moderate modulation order should be chose carefully in practical system.
{"title":"A BICM-MD-ID scheme in FFH system for combatting partial-band interference","authors":"J. Dai, D. Guo, Bangning Zhang","doi":"10.1109/WCSP.2010.5632008","DOIUrl":"https://doi.org/10.1109/WCSP.2010.5632008","url":null,"abstract":"An iterative decoding scheme with diversity is proposed for LDPC coded FFH/MFSK system under partial-band interference. The performance gain is obtained by soft-information exchange between demodulator and decoder. Extrinsic information transfer (EXIT) chart is employed to study the iterative procedure, which indicates that the convergence speed of the system is fast. The simulation results show the presented scheme outperforms traditional FFH/BFSK system, and the gain increases as the jamming probability increases. In addition, a moderate modulation order should be chose carefully in practical system.","PeriodicalId":448094,"journal":{"name":"2010 International Conference on Wireless Communications & Signal Processing (WCSP)","volume":"61 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114685278","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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