Pub Date : 2005-10-31DOI: 10.1109/ISIT.2005.1523314
Siu-Wai Ho
It is well known that the Shannon information measures are continuous functions of the probability distribution when the support is finite. This, however, does not hold when the support is countably infinite. In this paper, we investigate the continuity of the Shannon information measures for countably infinite support. With respect to a distance based on the Kullback-Liebler divergence, we use two different approaches to show that all the Shannon information measures are in fact discontinuous at all probability distributions with countably infinite support
{"title":"On the discontinuity of the Shannon information measures and typical sequences","authors":"Siu-Wai Ho","doi":"10.1109/ISIT.2005.1523314","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523314","url":null,"abstract":"It is well known that the Shannon information measures are continuous functions of the probability distribution when the support is finite. This, however, does not hold when the support is countably infinite. In this paper, we investigate the continuity of the Shannon information measures for countably infinite support. With respect to a distance based on the Kullback-Liebler divergence, we use two different approaches to show that all the Shannon information measures are in fact discontinuous at all probability distributions with countably infinite support","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73467594","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523525
Haiquan Wang, Dong Wang, X. Xia
In this paper, we first present a necessary and sufficient condition on linear transformations for an QOSTBC to possess the minimum ML decoding complexity, i.e., real symbol pair-wise decoding. We then present optimal linear transformations of information symbols for quasi-orthogonal space-time block codes (QOSTBC) with minimum ML decoding complexity. The optimality is in the sense that the diversity product (or product distance) is maximized when the mean transmission power is fixed
{"title":"On optimal quasi-orthogonal space-time block codes with minimum decoding complexity","authors":"Haiquan Wang, Dong Wang, X. Xia","doi":"10.1109/ISIT.2005.1523525","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523525","url":null,"abstract":"In this paper, we first present a necessary and sufficient condition on linear transformations for an QOSTBC to possess the minimum ML decoding complexity, i.e., real symbol pair-wise decoding. We then present optimal linear transformations of information symbols for quasi-orthogonal space-time block codes (QOSTBC) with minimum ML decoding complexity. The optimality is in the sense that the diversity product (or product distance) is maximized when the mean transmission power is fixed","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77944448","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523608
Y. Sung, L. Tong, H. Poor
The performance of Neyman-Pearson detection of correlated stochastic signals using noisy observations is investigated via the error exponent for the miss probability with a fixed level. Using the state-space structure of the signal and observation model, a closed-form expression for the error exponent is derived, and the connection between the asymptotic behavior of the optimal detector and that of the Kalman filter is established. The properties of the error exponent are investigated for the scalar case. It is shown that the error exponent has distinct characteristics with respect to correlation strength: for signal-to-noise ratio (SNR) > 1 the error exponent decreases monotonically as the correlation becomes stronger, whereas for SNR < 1 there is an optimal correlation that maximizes the error exponent for a given SNR
{"title":"Neyman-Pearson Detection of Gauss-Markov Signals in Noise: Closed-Form Error Exponent and Properties","authors":"Y. Sung, L. Tong, H. Poor","doi":"10.1109/ISIT.2005.1523608","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523608","url":null,"abstract":"The performance of Neyman-Pearson detection of correlated stochastic signals using noisy observations is investigated via the error exponent for the miss probability with a fixed level. Using the state-space structure of the signal and observation model, a closed-form expression for the error exponent is derived, and the connection between the asymptotic behavior of the optimal detector and that of the Kalman filter is established. The properties of the error exponent are investigated for the scalar case. It is shown that the error exponent has distinct characteristics with respect to correlation strength: for signal-to-noise ratio (SNR) > 1 the error exponent decreases monotonically as the correlation becomes stronger, whereas for SNR < 1 there is an optimal correlation that maximizes the error exponent for a given SNR","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73573838","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523749
Jie Luo, A. Ephremides
This paper studies finite-terminal random multiple access over a standard multi-packet reception (MPR) channel. In the first part of the paper, we show that if the MPR channel is standard, the throughput region of random multiple access is co-ordinate convex. We then study the information capacity region of multiple access without code synchronization and feedback. We show that the asymptotic capacity region is identical to the throughput region. In the second part of the paper, we study the stability region of ALOHA multiple access. For a class of packet arrival distributions, we show that the stationary distribution of the queues possesses the positive and strong positive correlation properties; and this consequently gives an outer bound to the stability region. We also show that if a conjectured "sensitivity monotonicity" property can be shown for the stationary distribution of the queues, then the equivalence between the closure of the stability region and the throughput region follows as a direct consequence, irrespective of the packet arrival distributions
{"title":"On the throughput, capacity and stability regions of random multiple access over standard multi-packet reception channels","authors":"Jie Luo, A. Ephremides","doi":"10.1109/ISIT.2005.1523749","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523749","url":null,"abstract":"This paper studies finite-terminal random multiple access over a standard multi-packet reception (MPR) channel. In the first part of the paper, we show that if the MPR channel is standard, the throughput region of random multiple access is co-ordinate convex. We then study the information capacity region of multiple access without code synchronization and feedback. We show that the asymptotic capacity region is identical to the throughput region. In the second part of the paper, we study the stability region of ALOHA multiple access. For a class of packet arrival distributions, we show that the stationary distribution of the queues possesses the positive and strong positive correlation properties; and this consequently gives an outer bound to the stability region. We also show that if a conjectured \"sensitivity monotonicity\" property can be shown for the stationary distribution of the queues, then the equivalence between the closure of the stability region and the throughput region follows as a direct consequence, irrespective of the packet arrival distributions","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82006605","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523468
S. Pawar, K. R. Kumar, P. V. Kumar, P. Elia, B. Sethuraman
For the quasi-static, Rayleigh-fading MIMO channel with nt transmit and nr receive antennas, Zheng and Tse showed that there exists a fundamental tradeoff between diversity and multiplexing gains, referred to as the diversity-multiplexing gain (D-MG) tradeoff. Explicit constructions for D-MG optimal ST codes are now available. In a subsequent paper, El Gamal, Caire and Damen considered signaling across the quasi-static ST channel using an L-round ARQ protocol that assumes the presence of a noiseless feedback channel capable of conveying one bit of information (ACK or NACK) per use of the feedback channel. They showed that given a fixed number of ARQ rounds L, there is a tradeoff between diversity and multiplexing gains under which the optimum diversity gain of the ARQ channel transmitting R = r log(SNR) bits per channel use, is that of the quasi-static channel without feedback investigated by Zheng and Tse, transmitting at (1/L)th the information rate. This tradeoff, which now is a function of the number L of ARQ rounds, is termed the diversity-multiplexing gain-delay (DMD) tradeoff. In the current paper, a sufficient condition under which a ST code will achieve the DMD tradeoff is presented for the case nr ges nt. The cyclic-division-algebra-based constructions of DMG optimal ST codes by Elia et. al. are then modified to yield codes which meet this sufficient criterion and are thereby DMD-optimal. This modification requires that either nt|L or L|nt
对于具有nt发射天线和nr接收天线的准静态瑞利衰落MIMO信道，Zheng和Tse表明在分集和复用增益之间存在基本的权衡，称为分集-复用增益(D-MG)权衡。D-MG最优ST规范的显式结构现在是可用的。在随后的一篇论文中，El Gamal, Caire和Damen考虑了使用l轮ARQ协议跨准静态ST信道的信令，该协议假设存在一个能够在每次使用反馈信道时传输1位信息(ACK或NACK)的无噪声反馈信道。他们表明，给定固定数量的ARQ轮数L，在分集增益和复用增益之间存在权衡，在这种情况下，每通道使用R = R log(SNR)比特的ARQ信道的最佳分集增益是Zheng和Tse研究的无反馈的准静态信道的分集增益，以(1/L)的信息速率传输。这种权衡现在是ARQ轮数L的函数，称为分集复用增益延迟(DMD)权衡。在本文中，本文给出了一个充分条件，在此条件下，ST码将实现DMD权衡。然后修改Elia等人基于循环除法代数的DMG最优ST码结构，以产生满足该充分准则的码，从而实现DMD最优。这个修改要求nt|L或L|nt
{"title":"Achieving the DMD tradeoff of the MIMO-ARQ channel","authors":"S. Pawar, K. R. Kumar, P. V. Kumar, P. Elia, B. Sethuraman","doi":"10.1109/ISIT.2005.1523468","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523468","url":null,"abstract":"For the quasi-static, Rayleigh-fading MIMO channel with nt transmit and nr receive antennas, Zheng and Tse showed that there exists a fundamental tradeoff between diversity and multiplexing gains, referred to as the diversity-multiplexing gain (D-MG) tradeoff. Explicit constructions for D-MG optimal ST codes are now available. In a subsequent paper, El Gamal, Caire and Damen considered signaling across the quasi-static ST channel using an L-round ARQ protocol that assumes the presence of a noiseless feedback channel capable of conveying one bit of information (ACK or NACK) per use of the feedback channel. They showed that given a fixed number of ARQ rounds L, there is a tradeoff between diversity and multiplexing gains under which the optimum diversity gain of the ARQ channel transmitting R = r log(SNR) bits per channel use, is that of the quasi-static channel without feedback investigated by Zheng and Tse, transmitting at (1/L)th the information rate. This tradeoff, which now is a function of the number L of ARQ rounds, is termed the diversity-multiplexing gain-delay (DMD) tradeoff. In the current paper, a sufficient condition under which a ST code will achieve the DMD tradeoff is presented for the case nr ges nt. The cyclic-division-algebra-based constructions of DMG optimal ST codes by Elia et. al. are then modified to yield codes which meet this sufficient criterion and are thereby DMD-optimal. This modification requires that either nt|L or L|nt","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88225920","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523527
K. Gowda, B. Rajan
This paper presents a systematic technique for constructing STBC-schemes (space-time block code schemes) with non-vanishing determinant, based on cyclic division algebras. Prior constructions of STBC-schemes with non-vanishing determinant are available only for 2,3,4 and 6 transmit antennas. In this paper, by using an appropriate representation of a cyclic division algebra over a maximal subfield, we construct STBC-schemes with non-vanishing determinant for the number of transmit antennas of the form 2k or 3middot2k or 2middot3k or qk(q - 1)/2, where q is a prime of the form 4s + 3 and s is any arbitrary integer. In a recent work, Elia et. al. have proved that non-vanishing determinant is a sufficient condition for STBC-schemes from cyclic division algebra to achieve the optimal diversity-multiplexing gain (D-MG) tradeoff; thus proving that the STBC-schemes constructed in this paper achieve the optimal D-MG tradeoff
{"title":"STBC-schemes with non-vanishing determinant for certain number of transmit antennas","authors":"K. Gowda, B. Rajan","doi":"10.1109/ISIT.2005.1523527","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523527","url":null,"abstract":"This paper presents a systematic technique for constructing STBC-schemes (space-time block code schemes) with non-vanishing determinant, based on cyclic division algebras. Prior constructions of STBC-schemes with non-vanishing determinant are available only for 2,3,4 and 6 transmit antennas. In this paper, by using an appropriate representation of a cyclic division algebra over a maximal subfield, we construct STBC-schemes with non-vanishing determinant for the number of transmit antennas of the form 2k or 3middot2k or 2middot3k or qk(q - 1)/2, where q is a prime of the form 4s + 3 and s is any arbitrary integer. In a recent work, Elia et. al. have proved that non-vanishing determinant is a sufficient condition for STBC-schemes from cyclic division algebra to achieve the optimal diversity-multiplexing gain (D-MG) tradeoff; thus proving that the STBC-schemes constructed in this paper achieve the optimal D-MG tradeoff","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74423906","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523673
Zheng Zhang, T. Duman
In this paper, we develop capacity approaching turbo coding schemes for half-duplex relay systems as an extension of our previous work on the full-duplex relay systems. We design the codes to be used at the source and the relay nodes, and develop an information combining technique at the destination node. In addition, by utilizing information theoretical results, we compute the optimal fraction of time during which the relay node should listen, and use it in the design of capacity approaching coding/decoding schemes. We observe that the performance of the practical coding schemes proposed is about 1.2 dB away from the theoretical limits (for a variety of channel models)
{"title":"Capacity approaching turbo coding for half duplex relaying","authors":"Zheng Zhang, T. Duman","doi":"10.1109/ISIT.2005.1523673","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523673","url":null,"abstract":"In this paper, we develop capacity approaching turbo coding schemes for half-duplex relay systems as an extension of our previous work on the full-duplex relay systems. We design the codes to be used at the source and the relay nodes, and develop an information combining technique at the destination node. In addition, by utilizing information theoretical results, we compute the optimal fraction of time during which the relay node should listen, and use it in the design of capacity approaching coding/decoding schemes. We observe that the performance of the practical coding schemes proposed is about 1.2 dB away from the theoretical limits (for a variety of channel models)","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77877896","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523740
J. Giese, M. Skoglund
We consider the design of space-time constellations when the channel state information that is available at the receiver is an estimate of the channel coefficients with known error covariance. This setup encompasses the well-studied scenarios of perfect and no channel knowledge and allows a smooth transition between these two cases. We perform an asymptotic pairwise error probability analysis and derive a criterion to design constellations matched to the level of channel knowledge available at the receiver. Moreover, we use the criterion to assess the power tradeoff between data transmission and channel coefficient acquisition for any given specific set of constellations. Simulation results illustrate the benefit of the proposed criterion
{"title":"Space-time constellation design for partial CSI at the receiver","authors":"J. Giese, M. Skoglund","doi":"10.1109/ISIT.2005.1523740","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523740","url":null,"abstract":"We consider the design of space-time constellations when the channel state information that is available at the receiver is an estimate of the channel coefficients with known error covariance. This setup encompasses the well-studied scenarios of perfect and no channel knowledge and allows a smooth transition between these two cases. We perform an asymptotic pairwise error probability analysis and derive a criterion to design constellations matched to the level of channel knowledge available at the receiver. Moreover, we use the criterion to assess the power tradeoff between data transmission and channel coefficient acquisition for any given specific set of constellations. Simulation results illustrate the benefit of the proposed criterion","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80703705","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523661
T. Tabet, S. Dusad, R. Knopp
In this paper, we present an efficient protocol for the delay-limited fading automatic retransmission request single relay channel. The source is using an ARQ retransmission protocol to send data to the relay and the destination. When the relay is able to decode, both the relay and the source send the same data to the destination providing additional gains. The proposed protocol exploits two kinds of diversity: (i) space diversity available through the cooperative (relay) terminal, which retransmits the source's signals, (ii) ARQ diversity obtained by leveraging the retransmission delay to enhance the reliability. The performance characterization is in terms of the achievable diversity, multiplexing gain and delay tradeoff for a high signal-to-noise ratio (snr) regime
{"title":"Achievable diversity-multiplexing-delay tradeoff in half-duplex ARQ relay channels","authors":"T. Tabet, S. Dusad, R. Knopp","doi":"10.1109/ISIT.2005.1523661","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523661","url":null,"abstract":"In this paper, we present an efficient protocol for the delay-limited fading automatic retransmission request single relay channel. The source is using an ARQ retransmission protocol to send data to the relay and the destination. When the relay is able to decode, both the relay and the source send the same data to the destination providing additional gains. The proposed protocol exploits two kinds of diversity: (i) space diversity available through the cooperative (relay) terminal, which retransmits the source's signals, (ii) ARQ diversity obtained by leveraging the retransmission delay to enhance the reliability. The performance characterization is in terms of the achievable diversity, multiplexing gain and delay tradeoff for a high signal-to-noise ratio (snr) regime","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85887235","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 : 2005-10-31DOI: 10.1109/ISIT.2005.1523315
P. Harremoës
A new maximal inequality for non-negative martingales is proved. It strengthens a well-known maximal inequality by Doob, and it is demonstrated that the stated inequality is tight. The inequality emphasizes the relation between martingales and information divergence. It implies pointwise convergence of X log X bounded martingales. A similar inequality holds for ergodic sequences. Relations to the Shannon-McMillan-Breiman theorem and Markov chains are mentioned
{"title":"Martingales and information divergence","authors":"P. Harremoës","doi":"10.1109/ISIT.2005.1523315","DOIUrl":"https://doi.org/10.1109/ISIT.2005.1523315","url":null,"abstract":"A new maximal inequality for non-negative martingales is proved. It strengthens a well-known maximal inequality by Doob, and it is demonstrated that the stated inequality is tight. The inequality emphasizes the relation between martingales and information divergence. It implies pointwise convergence of X log X bounded martingales. A similar inequality holds for ergodic sequences. Relations to the Shannon-McMillan-Breiman theorem and Markov chains are mentioned","PeriodicalId":92224,"journal":{"name":"International Symposium on Information Theory and its Applications. International Symposium on Information Theory and its Applications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86013274","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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