Pub Date : 2008-10-01DOI: 10.1109/ACSSC.2008.5074461
D. Day
New nonlinear decision rules for performing noncoherent integration (NCI) of multiple radar dwells are determined. Conventional noncoherent integration followed by CFAR can be greatly desensitized when the noise energy varies from dwell to dwell. The new rules are robust to dwell to dwell variations in noise energy, providing CFAR and minimizing detection loss. For slow fluctuation target models the locally most powerful decision rule outperforms conventional NCI even in stationary noise conditions. In addition, a composite test is provided that outperforms all individual binary integration (BI) M out of N tests independent of target fluctuation model and is suitable for distributed detection.
{"title":"Nonlinear decision rules for robust noncoherent integration","authors":"D. Day","doi":"10.1109/ACSSC.2008.5074461","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074461","url":null,"abstract":"New nonlinear decision rules for performing noncoherent integration (NCI) of multiple radar dwells are determined. Conventional noncoherent integration followed by CFAR can be greatly desensitized when the noise energy varies from dwell to dwell. The new rules are robust to dwell to dwell variations in noise energy, providing CFAR and minimizing detection loss. For slow fluctuation target models the locally most powerful decision rule outperforms conventional NCI even in stationary noise conditions. In addition, a composite test is provided that outperforms all individual binary integration (BI) M out of N tests independent of target fluctuation model and is suitable for distributed detection.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125512682","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074598
H. Rowaihy, Matthew P. Johnson, S. Eswaran, D. Pizzocaro, A. Bar-Noy, T. L. Porta, A. Misra, A. Preece
Task-centric wireless sensor network environments are often characterized by the simultaneous operation of multiple tasks. Individual tasks compete for constrained resources and thus need resource mediation algorithms at two levels. First, different sensors must be allocated to different tasks based on the combination of sensor attributes and task requirements. Subsequently, sensor data rates on various data routes must be dynamically adapted to share the available wireless bandwidth, especially when links experience traffic congestion. In this paper we investigate heuristics for incrementally modifying the sensor-task matching process to incorporate changes in the transport capacity constraints or feasible task utility values.
{"title":"Utility-based joint sensor selection and congestion control for task-oriented WSNs","authors":"H. Rowaihy, Matthew P. Johnson, S. Eswaran, D. Pizzocaro, A. Bar-Noy, T. L. Porta, A. Misra, A. Preece","doi":"10.1109/ACSSC.2008.5074598","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074598","url":null,"abstract":"Task-centric wireless sensor network environments are often characterized by the simultaneous operation of multiple tasks. Individual tasks compete for constrained resources and thus need resource mediation algorithms at two levels. First, different sensors must be allocated to different tasks based on the combination of sensor attributes and task requirements. Subsequently, sensor data rates on various data routes must be dynamically adapted to share the available wireless bandwidth, especially when links experience traffic congestion. In this paper we investigate heuristics for incrementally modifying the sensor-task matching process to incorporate changes in the transport capacity constraints or feasible task utility values.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126819117","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074826
I. Wong, B. Evans
Optimizing OFDMA resource allocation with respect to communication performance requires solving a nonlinear mixed-integer programming problem. As a result, many researchers have fallen back on suboptimal heuristic algorithms. In a recent paper, we demonstrate that ergodic rate maximization is possible using a dual optimization framework that results in a practically optimal solution with complexity that is on the order of the number of subcarriers times the number of users. One of the primary disadvantages of considering ergodic rates is the assumption that the channel distribution information (CDI) is perfectly known at the transmitter. Therefore, this paper proposes an adaptive algorithm based on stochastic approximation methods that do not require knowledge of the CDI. This algorithm converges to the optimal solution with probability one, while for each OFDMA symbol, the complexity is on the order of the number of subcarriers times the number of users. There are no iterations in a given OFDMA symbol time; instead, the ldquoiterationsrdquo are actually performed across time (symbols). Simulation results based roughly on a third-generation partnership project, long-term evolution (3GPP-LTE) OFDMA system corroborate our claims.
{"title":"Adaptive downlink OFDMA resource allocation","authors":"I. Wong, B. Evans","doi":"10.1109/ACSSC.2008.5074826","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074826","url":null,"abstract":"Optimizing OFDMA resource allocation with respect to communication performance requires solving a nonlinear mixed-integer programming problem. As a result, many researchers have fallen back on suboptimal heuristic algorithms. In a recent paper, we demonstrate that ergodic rate maximization is possible using a dual optimization framework that results in a practically optimal solution with complexity that is on the order of the number of subcarriers times the number of users. One of the primary disadvantages of considering ergodic rates is the assumption that the channel distribution information (CDI) is perfectly known at the transmitter. Therefore, this paper proposes an adaptive algorithm based on stochastic approximation methods that do not require knowledge of the CDI. This algorithm converges to the optimal solution with probability one, while for each OFDMA symbol, the complexity is on the order of the number of subcarriers times the number of users. There are no iterations in a given OFDMA symbol time; instead, the ldquoiterationsrdquo are actually performed across time (symbols). Simulation results based roughly on a third-generation partnership project, long-term evolution (3GPP-LTE) OFDMA system corroborate our claims.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114933510","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074565
M. Schellmann, L. Thiele, V. Jungnickel
In high-mobility OFDM systems, Doppler distortions cause inter-carrier interference (ICI) that may degrade the system performance severely. Although thoroughly studied, hardly any approaches for ICI estimation and compensation exist that maintain the OFDM-specific subcarrier-wise signal processing and thus provide a solution with reasonable demands on complexity. For a multi-antenna receiver, this paper proposes such an approach which relies on optimum combining of the signals from the different receive antennas. The ICI is characterized in terms of a frequency-selective interference function, which can be estimated by simple means using common pilot signals.
{"title":"Low-complexity Doppler compensation in mobile SIMO-OFDM systems","authors":"M. Schellmann, L. Thiele, V. Jungnickel","doi":"10.1109/ACSSC.2008.5074565","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074565","url":null,"abstract":"In high-mobility OFDM systems, Doppler distortions cause inter-carrier interference (ICI) that may degrade the system performance severely. Although thoroughly studied, hardly any approaches for ICI estimation and compensation exist that maintain the OFDM-specific subcarrier-wise signal processing and thus provide a solution with reasonable demands on complexity. For a multi-antenna receiver, this paper proposes such an approach which relies on optimum combining of the signals from the different receive antennas. The ICI is characterized in terms of a frequency-selective interference function, which can be estimated by simple means using common pilot signals.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115180471","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074837
K. Minoo, Truong Q. Nguyen
In this paper a novel method to estimate the required bits for representing the coded (quantized) coefficients within a block of natural video sequences is proposed. The proposed method assumes a parameterized probabilistic model for coded data and utilizes a maximum likelihood parameter estimation technique to estimate the model's parameters. The proposed method achieves a robust estimation of the rate based on the estimated probability of each coefficient based on zero order entropy. The rate estimation via maximum likelihood parameter estimation enjoys lower computational complexity, compared to the actual entropy coding of the data. For the purpose of rate estimation we consider a number of options to estimate the parameters of the probabilistic model of coded data. In the context optimal mode selection within the H.264/AVC video codec, the rate estimation method is used to estimate a Lagrangian rate-distortion cost which would be minimized for the optimal mode. The experimental results show that the proposed method considerably reduces the computational complexity while maintaining almost the same rate-distortion coding efficiency compared to mode selection using the actual rate.
{"title":"Rate estimation via maximum likelihood parameter estimation: Application in fast mode-selection within the H.264/AVC","authors":"K. Minoo, Truong Q. Nguyen","doi":"10.1109/ACSSC.2008.5074837","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074837","url":null,"abstract":"In this paper a novel method to estimate the required bits for representing the coded (quantized) coefficients within a block of natural video sequences is proposed. The proposed method assumes a parameterized probabilistic model for coded data and utilizes a maximum likelihood parameter estimation technique to estimate the model's parameters. The proposed method achieves a robust estimation of the rate based on the estimated probability of each coefficient based on zero order entropy. The rate estimation via maximum likelihood parameter estimation enjoys lower computational complexity, compared to the actual entropy coding of the data. For the purpose of rate estimation we consider a number of options to estimate the parameters of the probabilistic model of coded data. In the context optimal mode selection within the H.264/AVC video codec, the rate estimation method is used to estimate a Lagrangian rate-distortion cost which would be minimized for the optimal mode. The experimental results show that the proposed method considerably reduces the computational complexity while maintaining almost the same rate-distortion coding efficiency compared to mode selection using the actual rate.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116041740","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074797
F. Dovis, M. Fantino, M. Pini
In a global navigation satellite system (GGNS) receiver the acquisition algorithms as well as the signal tracking play an important role in the receiver functioning. When the receiver is implemented in software radio technology the demanding computational complexity becomes a critical issue as much as the algorithms performance and stability. This paper presents the solutions adopted for the signal acquisition and tracking for the N-Gene fully software receiver. The acquisition algorithm is a variant of the classical "fast acquisition algorithm" where the signal correlation is obtained in time domain by means of two Fast Fourier Transforms (FFTs) and a single inverse fast Fourier transform (IFFT). A solution for improving the tracking performance in case of low C/N0, is also proposed. The work on the signal tracking focuses on a robust normalization of the discrimination functions within the tracking loops. The algorithms are presented highlighting case by case the advantages both in terms of computational complexity, robustness and performance.
{"title":"Efficient signal acquisition and tracking for a real time GPS/Galileo software receiver","authors":"F. Dovis, M. Fantino, M. Pini","doi":"10.1109/ACSSC.2008.5074797","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074797","url":null,"abstract":"In a global navigation satellite system (GGNS) receiver the acquisition algorithms as well as the signal tracking play an important role in the receiver functioning. When the receiver is implemented in software radio technology the demanding computational complexity becomes a critical issue as much as the algorithms performance and stability. This paper presents the solutions adopted for the signal acquisition and tracking for the N-Gene fully software receiver. The acquisition algorithm is a variant of the classical \"fast acquisition algorithm\" where the signal correlation is obtained in time domain by means of two Fast Fourier Transforms (FFTs) and a single inverse fast Fourier transform (IFFT). A solution for improving the tracking performance in case of low C/N0, is also proposed. The work on the signal tracking focuses on a robust normalization of the discrimination functions within the tracking loops. The algorithms are presented highlighting case by case the advantages both in terms of computational complexity, robustness and performance.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"158 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116110072","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074523
H. Buchner, S. Spors
Wave-domain adaptive filtering (WDAF) was introduced as an efficient spatio-temporal generalization of the popular frequency-domain adaptive filtering (FDAF). Through the incorporation of the mathematical foundations on wavefields, WDAF is suitable even for massive MIMO systems with highly cross-correlated broadband input signals. In this paper, we present a new rigorous derivation of WDAF leading to a whole class of powerful MIMO adaptation algorithms within a compact matrix framework. We show efficient approximations which provide both new efficient WDAF realizations and interesting links to well-known algorithms (including the various FDAF algorithms). Due to the rigorous approach, we obtain important practical design rules.
{"title":"A general derivation of Wave-Domain Adaptive Filtering and application to acoustic echo cancellation","authors":"H. Buchner, S. Spors","doi":"10.1109/ACSSC.2008.5074523","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074523","url":null,"abstract":"Wave-domain adaptive filtering (WDAF) was introduced as an efficient spatio-temporal generalization of the popular frequency-domain adaptive filtering (FDAF). Through the incorporation of the mathematical foundations on wavefields, WDAF is suitable even for massive MIMO systems with highly cross-correlated broadband input signals. In this paper, we present a new rigorous derivation of WDAF leading to a whole class of powerful MIMO adaptation algorithms within a compact matrix framework. We show efficient approximations which provide both new efficient WDAF realizations and interesting links to well-known algorithms (including the various FDAF algorithms). Due to the rigorous approach, we obtain important practical design rules.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122874984","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074671
K. Bakanoglu, S. Tomasin, E. Erkip
A cooperative network where transmission between two nodes that have no direct link, but assisted by many relays is considered. We assume a broadband system, such as OFDM, modeled by multiple parallel Gaussian subchannels between the source and each relay, and also between each relay and the destination. We formulate the optimization problem for joint power and subchannel allocation under a short term per-node power constraint to maximize the instantaneous total transmission rate between the source and the destination. To solve this optimization problem, first we find the optimal power allocation for a given subchannel allocation. Then we focus on a greedy algorithm that jointly allocates subchannels and power. Simulation results reveal that our proposed algorithm results in rates close to the optimum allocation.
{"title":"Resource allocation in wireless networks with multiple relays","authors":"K. Bakanoglu, S. Tomasin, E. Erkip","doi":"10.1109/ACSSC.2008.5074671","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074671","url":null,"abstract":"A cooperative network where transmission between two nodes that have no direct link, but assisted by many relays is considered. We assume a broadband system, such as OFDM, modeled by multiple parallel Gaussian subchannels between the source and each relay, and also between each relay and the destination. We formulate the optimization problem for joint power and subchannel allocation under a short term per-node power constraint to maximize the instantaneous total transmission rate between the source and the destination. To solve this optimization problem, first we find the optimal power allocation for a given subchannel allocation. Then we focus on a greedy algorithm that jointly allocates subchannels and power. Simulation results reveal that our proposed algorithm results in rates close to the optimum allocation.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122929791","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074451
M. Bennis, M. Debbah, J. Lilleberg
In this paper, we study the performance of point-to-point communication in self-organized networks. An information-theoretic framework is considered to determine the optimum transmission power enabling reliable communication between neighboring nodes at a certain user requested rate. Realistic channel models taking into account path-loss and fading are also considered. Optimal power allocation strategies are investigated. For this purpose, we use the ergodic capacity as a criterion for information-theoretic analysis. In the first case, the transmit power is the same for all pairs. In a more opportunistic case, different transmit pairs use different transmit powers according to their channel realizations. Then, for a given rate requirement C, we derive the optimal close-talker distance that meets the requirement for a given power P. Numerical results are finally presented giving insights into the design of power adaptation schemes for point-to-point communications.
{"title":"Opportunistic power allocation for point-to-point communication in self-organized networks","authors":"M. Bennis, M. Debbah, J. Lilleberg","doi":"10.1109/ACSSC.2008.5074451","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074451","url":null,"abstract":"In this paper, we study the performance of point-to-point communication in self-organized networks. An information-theoretic framework is considered to determine the optimum transmission power enabling reliable communication between neighboring nodes at a certain user requested rate. Realistic channel models taking into account path-loss and fading are also considered. Optimal power allocation strategies are investigated. For this purpose, we use the ergodic capacity as a criterion for information-theoretic analysis. In the first case, the transmit power is the same for all pairs. In a more opportunistic case, different transmit pairs use different transmit powers according to their channel realizations. Then, for a given rate requirement C, we derive the optimal close-talker distance that meets the requirement for a given power P. Numerical results are finally presented giving insights into the design of power adaptation schemes for point-to-point communications.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"26 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122865196","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 : 2008-10-01DOI: 10.1109/ACSSC.2008.5074419
R. Tresch, C. Mehlführer, M. Guillaud
An LMMSE channel estimator is proposed for the downlink of a MIMO W-CDMA system. The estimation takes into account intra-cell and out-of-cell interference, as well as receive-side spatial correlation. Efficient numerical methods are applied to solve the resulting large block Toeplitz linear equation sets. Various simplifying assumptions about the prior knowledge of second-order statistics used by the estimator are investigated, providing a performance vs. complexity tradeoff. Link level simulation results of a MIMO HSDPA system show that LMMSE channel estimation together with out-of-cell interference-aware equalization yield performance throughput gains of up to 30% over a correlation based channel estimator.
{"title":"LMMSE channel estimation for MIMO W-CDMA with out-of-cell interference mitigation","authors":"R. Tresch, C. Mehlführer, M. Guillaud","doi":"10.1109/ACSSC.2008.5074419","DOIUrl":"https://doi.org/10.1109/ACSSC.2008.5074419","url":null,"abstract":"An LMMSE channel estimator is proposed for the downlink of a MIMO W-CDMA system. The estimation takes into account intra-cell and out-of-cell interference, as well as receive-side spatial correlation. Efficient numerical methods are applied to solve the resulting large block Toeplitz linear equation sets. Various simplifying assumptions about the prior knowledge of second-order statistics used by the estimator are investigated, providing a performance vs. complexity tradeoff. Link level simulation results of a MIMO HSDPA system show that LMMSE channel estimation together with out-of-cell interference-aware equalization yield performance throughput gains of up to 30% over a correlation based channel estimator.","PeriodicalId":416114,"journal":{"name":"2008 42nd Asilomar Conference on Signals, Systems and Computers","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123013407","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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