Pub Date : 2001-10-28DOI: 10.1109/MILCOM.2001.985801
Peixiang Gong, M. Lee, T. Saadawi
In this paper, we present a delay differentiation based QoS architecture for supporting real-time multimedia services in the core-stateless IP networks. The key component of our approach is a three-level class-based scheduling scheme. Based upon it, we propose the Delay Differentiation with Earliest-Deadline-First (DD-EDF) QoS architecture. Simulation shows that our approach can achieve better end-to-end/per-hop average queueing delay performance with higher link utilization, when compared with the scheme without DD-EDF.
{"title":"A novel delay differentiation QoS architecture","authors":"Peixiang Gong, M. Lee, T. Saadawi","doi":"10.1109/MILCOM.2001.985801","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.985801","url":null,"abstract":"In this paper, we present a delay differentiation based QoS architecture for supporting real-time multimedia services in the core-stateless IP networks. The key component of our approach is a three-level class-based scheduling scheme. Based upon it, we propose the Delay Differentiation with Earliest-Deadline-First (DD-EDF) QoS architecture. Simulation shows that our approach can achieve better end-to-end/per-hop average queueing delay performance with higher link utilization, when compared with the scheme without DD-EDF.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116809916","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.986041
M. Joham, Y. Sun, M. Zoltowski, M. Honig, J. S. Goldstein
The multi-stage nested Wiener filter (MSNWF) can be identified to be the solution of the Wiener-Hopf equation in the Krylov subspace of the covariance matrix of the observation and the crosscorrelation vector of the observation and the desired signal. Therefore, the Arnoldi algorithm which arises from the MSNWF development can be replaced by the Lanczos algorithm leading to a simpler computation of the Krylov subspace basis. Moreover, the foundation in the Krylov subspace framework helps to derive an order-recursive representation of the MSNWF which generates the filter for rank D in terms of the filter for rank D-1. The new backward recursion is used to design a linear equalizer filter in an enhanced data rates for GSM evolution (EDGE) system. Simulation results show the ability of the MSNWF to reduce the receiver complexity while the system performance is unchanged.
{"title":"A new backward recursion for the multi-stage nested Wiener filter employing Krylov subspace methods","authors":"M. Joham, Y. Sun, M. Zoltowski, M. Honig, J. S. Goldstein","doi":"10.1109/MILCOM.2001.986041","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.986041","url":null,"abstract":"The multi-stage nested Wiener filter (MSNWF) can be identified to be the solution of the Wiener-Hopf equation in the Krylov subspace of the covariance matrix of the observation and the crosscorrelation vector of the observation and the desired signal. Therefore, the Arnoldi algorithm which arises from the MSNWF development can be replaced by the Lanczos algorithm leading to a simpler computation of the Krylov subspace basis. Moreover, the foundation in the Krylov subspace framework helps to derive an order-recursive representation of the MSNWF which generates the filter for rank D in terms of the filter for rank D-1. The new backward recursion is used to design a linear equalizer filter in an enhanced data rates for GSM evolution (EDGE) system. Simulation results show the ability of the MSNWF to reduce the receiver complexity while the system performance is unchanged.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115507976","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.985852
A. Hansson, J. Nilsson, M. Skold, U. Sterner
Two types of tactical radio networks are analyzed and compared. Firstly we consider a multi-hop ad-hoc network and secondly a WCDMA cellular network based on the new UMTS terrestrial radio access network called UTRAN. We are interested in how an ad-hoc network behaves and compares to a cellular network with a limited number of base stations, in a mobile scenario. For the assessment, two tactical scenarios involving a Swedish mechanized battalion are drawn up for armed combat on Swedish ground. They are characterized by different mobility, where in the first we have constant movements over a large area and in the second only a high speed movement within a limited area at the end of the scenario. We test a service mix consisting of situation awareness data, group calls and intranet connections. We use a digitized terrain database for propagation modeling in the 300 MHz and the 1.5 GHz frequency bands. As a scenario elapses, at each time instant, the probability that the network can provide a service for an arbitrarily chosen radio terminal is estimated. Based on these results we finally assess the different network solutions.
{"title":"Scenario based comparison of cellular and ad-hoc tactical radio networks","authors":"A. Hansson, J. Nilsson, M. Skold, U. Sterner","doi":"10.1109/MILCOM.2001.985852","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.985852","url":null,"abstract":"Two types of tactical radio networks are analyzed and compared. Firstly we consider a multi-hop ad-hoc network and secondly a WCDMA cellular network based on the new UMTS terrestrial radio access network called UTRAN. We are interested in how an ad-hoc network behaves and compares to a cellular network with a limited number of base stations, in a mobile scenario. For the assessment, two tactical scenarios involving a Swedish mechanized battalion are drawn up for armed combat on Swedish ground. They are characterized by different mobility, where in the first we have constant movements over a large area and in the second only a high speed movement within a limited area at the end of the scenario. We test a service mix consisting of situation awareness data, group calls and intranet connections. We use a digitized terrain database for propagation modeling in the 300 MHz and the 1.5 GHz frequency bands. As a scenario elapses, at each time instant, the probability that the network can provide a service for an arbitrarily chosen radio terminal is estimated. Based on these results we finally assess the different network solutions.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114648389","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.985922
A. Mathur, T.M. Nguyen, G. Goo
The wideband gapfiller satellite communication links will employ several frequencies in the X-, K-, and Ka-bands. Appropriate rain models are required to evaluate the propagation degradation due to rain at these frequencies. This paper reviews some of the study results reported by the NASA-ACTS (National Aeronautics and Space Administration-advanced communications technology satellite) researchers for K- and Ka-band propagation. The ACTS measured attenuation data in the K- and Ka-bands is compared with data obtained from well-established rain model attenuation predictions. Based on such comparisons, recommendations are made for gapfiller applications, especially at communication frequencies of 20.0, 21.2 and 30.0 GHz.
{"title":"Rain attenuation model assessment for wideband gapfiller satellite communications link","authors":"A. Mathur, T.M. Nguyen, G. Goo","doi":"10.1109/MILCOM.2001.985922","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.985922","url":null,"abstract":"The wideband gapfiller satellite communication links will employ several frequencies in the X-, K-, and Ka-bands. Appropriate rain models are required to evaluate the propagation degradation due to rain at these frequencies. This paper reviews some of the study results reported by the NASA-ACTS (National Aeronautics and Space Administration-advanced communications technology satellite) researchers for K- and Ka-band propagation. The ACTS measured attenuation data in the K- and Ka-bands is compared with data obtained from well-established rain model attenuation predictions. Based on such comparisons, recommendations are made for gapfiller applications, especially at communication frequencies of 20.0, 21.2 and 30.0 GHz.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"196 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123547662","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.986053
Wen-Jye Huang, J. Doherty
Space division multiple access (SDMA) uses the advantage of the smart antenna technology to form a directional antenna pattern in a cellular. By exploiting the directional antenna pattern for users, SDMA can achieve spatial orthogonality among users and channel reuse within a cell. Several studies (Fuhl 1997; Buracchini et al. 1996) have shown the performance improvement of SDMA in a mobile communication environment. This paper extends the two-folding SDMA blocking probability derivation from Galvan-Tejada and Gardiner (1999) and approximately two-folding SDMA approaches from Huang and Doherty (2001). An approximate model is proposed for three-folding SDMA and the corresponding blocking probability is derived. Analytical and simulation results show that three-fold SDMA increases capacity over the traditional cellular system, which demonstrates the effectiveness of SDMA for resource management.
空分多址(SDMA)利用智能天线技术的优势，在蜂窝内形成定向天线方向图。通过利用用户的定向天线方向图，SDMA可以实现用户间的空间正交性和小区内的信道复用。几项研究(Fuhl 1997;Buracchini et al. 1996)已经证明了SDMA在移动通信环境下的性能改进。本文扩展了galvana - tejada和Gardiner(1999)的双折叠SDMA阻塞概率推导以及Huang和Doherty(2001)的近似双折叠SDMA方法。提出了三折叠SDMA的近似模型，并推导了相应的阻塞概率。分析和仿真结果表明，在传统蜂窝系统的基础上，三倍的SDMA增加了容量，证明了SDMA在资源管理方面的有效性。
{"title":"An evaluation of blocking probability for three-fold SDMA","authors":"Wen-Jye Huang, J. Doherty","doi":"10.1109/MILCOM.2001.986053","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.986053","url":null,"abstract":"Space division multiple access (SDMA) uses the advantage of the smart antenna technology to form a directional antenna pattern in a cellular. By exploiting the directional antenna pattern for users, SDMA can achieve spatial orthogonality among users and channel reuse within a cell. Several studies (Fuhl 1997; Buracchini et al. 1996) have shown the performance improvement of SDMA in a mobile communication environment. This paper extends the two-folding SDMA blocking probability derivation from Galvan-Tejada and Gardiner (1999) and approximately two-folding SDMA approaches from Huang and Doherty (2001). An approximate model is proposed for three-folding SDMA and the corresponding blocking probability is derived. Analytical and simulation results show that three-fold SDMA increases capacity over the traditional cellular system, which demonstrates the effectiveness of SDMA for resource management.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123868106","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.985990
M. Souryal, B. Vojcic, R. Pickholtz
In an ad hoc multihop CDMA network, fading can adversely affect the expected progress per hop of a packet. However, the effects of fading can be mitigated through route diversity, where a given source-destination pair has multiple possible paths through which to route packets. First, the distribution of the interference power is derived using a previously proposed model, and with Rayleigh fading the distribution is shown to be the same as for the non fading case except for a scaling factor. Expressions for the expected progress per hop are derived for the cases with and without next-hop route diversity. We find that the expected progress per hop in a Rayleigh fading channel can be significantly improved with low-order route diversity.
{"title":"Ad hoc, multihop CDMA networks with route diversity in a Rayleigh fading channel","authors":"M. Souryal, B. Vojcic, R. Pickholtz","doi":"10.1109/MILCOM.2001.985990","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.985990","url":null,"abstract":"In an ad hoc multihop CDMA network, fading can adversely affect the expected progress per hop of a packet. However, the effects of fading can be mitigated through route diversity, where a given source-destination pair has multiple possible paths through which to route packets. First, the distribution of the interference power is derived using a previously proposed model, and with Rayleigh fading the distribution is shown to be the same as for the non fading case except for a scaling factor. Expressions for the expected progress per hop are derived for the cases with and without next-hop route diversity. We find that the expected progress per hop in a Rayleigh fading channel can be significantly improved with low-order route diversity.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121328829","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.986090
Ping Xiong, I. Psaromiligkos, S. Batalama
We investigate the relative output SINR performance of two linear multiuser detectors - the full decorrelator and the partial decorrelator. For each detector, we consider two implementations that are equivalent under perfectly known input statistics. The first implementation utilizes the signature matrix while the second implementation is based on the eigendecomposition of the ideal input covariance matrix. While the full decorrelator aims at decorrelating the complete multiple-access-interference, the partial decorrelator aims at decorrelating only a part of it by excluding one or more user-signatures or eigenvectors from the corresponding implementation method. We derive necessary and sufficient conditions on the signal energy and signature cross-correlation levels under which the partial decorrelator outperforms the full decorrelator in the output SINR sense. Numerical results demonstrate the validity of the above conditions and simulation studies illustrate the relative SINR and BER performance of the full and partial decorrelators under sample-average-estimated input statistics.
{"title":"On the relative output SINR of the full and partial decorrelators","authors":"Ping Xiong, I. Psaromiligkos, S. Batalama","doi":"10.1109/MILCOM.2001.986090","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.986090","url":null,"abstract":"We investigate the relative output SINR performance of two linear multiuser detectors - the full decorrelator and the partial decorrelator. For each detector, we consider two implementations that are equivalent under perfectly known input statistics. The first implementation utilizes the signature matrix while the second implementation is based on the eigendecomposition of the ideal input covariance matrix. While the full decorrelator aims at decorrelating the complete multiple-access-interference, the partial decorrelator aims at decorrelating only a part of it by excluding one or more user-signatures or eigenvectors from the corresponding implementation method. We derive necessary and sufficient conditions on the signal energy and signature cross-correlation levels under which the partial decorrelator outperforms the full decorrelator in the output SINR sense. Numerical results demonstrate the validity of the above conditions and simulation studies illustrate the relative SINR and BER performance of the full and partial decorrelators under sample-average-estimated input statistics.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125141140","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.985774
L. Hong, K. C. Ho
Modulation classification is a technique that automatically identifies the modulation type of a received signal. It has found a variety of military and commercial applications. In some practical cases such as signal interception, the intercepted signal is very weak and a long observation time is needed to maintain an acceptable probability of correct identification. This paper presents an algorithm using a two element antenna array receiver for BPSK and QPSK classification to increase the probability of correct classification for a short data record. The approach is to perform the generalized likelihood ratio test. The unknown phase shift between the two received signals due to the spatial separation of the antenna elements is estimated using maximum likelihood or linear least squares technique. It is then used in the likelihood ratio test for classification. Simulations show that the proposed classifier has high accuracy and is superior to the classifier that has only one received antenna.
{"title":"Modulation classification of BPSK and QPSK signals using a two element antenna array receiver","authors":"L. Hong, K. C. Ho","doi":"10.1109/MILCOM.2001.985774","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.985774","url":null,"abstract":"Modulation classification is a technique that automatically identifies the modulation type of a received signal. It has found a variety of military and commercial applications. In some practical cases such as signal interception, the intercepted signal is very weak and a long observation time is needed to maintain an acceptable probability of correct identification. This paper presents an algorithm using a two element antenna array receiver for BPSK and QPSK classification to increase the probability of correct classification for a short data record. The approach is to perform the generalized likelihood ratio test. The unknown phase shift between the two received signals due to the spatial separation of the antenna elements is estimated using maximum likelihood or linear least squares technique. It is then used in the likelihood ratio test for classification. Simulations show that the proposed classifier has high accuracy and is superior to the classifier that has only one received antenna.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"163 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120851030","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.986102
C. Hessel
This paper explains the relationships between MIL-STD-188-181b, MIL-STD-188-184, High Performance Waveform modulation and High Performance Waveform protocol. We discuss the important features of each of these items, their similarities and differences, and how these various pieces do and do not work together. The paper discusses these issues with regard to non-DAMA satellite communications since, at the time of this writing, 181b and 184 are not officially part of DAMA.
{"title":"High Performance Waveform, MIL-STD-188-181b and MIL-STD-188-184: their differences, similarities and applications","authors":"C. Hessel","doi":"10.1109/MILCOM.2001.986102","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.986102","url":null,"abstract":"This paper explains the relationships between MIL-STD-188-181b, MIL-STD-188-184, High Performance Waveform modulation and High Performance Waveform protocol. We discuss the important features of each of these items, their similarities and differences, and how these various pieces do and do not work together. The paper discusses these issues with regard to non-DAMA satellite communications since, at the time of this writing, 181b and 184 are not officially part of DAMA.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"190 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124203389","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 : 2001-10-28DOI: 10.1109/MILCOM.2001.985993
J. S. Skinner, D. Noneaker
Mobile CDMA cellular networks for tactical applications require base-station mobility in order to provide communications on the move. Because of the mobility of the base stations and the lack of a high-speed wire-line network between base stations, handoff of mobiles among base stations is more difficult than in a commercial CDMA cellular network. In this paper, we examine the performance of the reverse links in a tactical CDMA cellular network using continuous transmission for packet data communications. In particular, we consider the effect of limited handoff capability on the reverse-link capacity of the network.
{"title":"Performance of reverse-link packet transmission in mobile cellular CDMA networks","authors":"J. S. Skinner, D. Noneaker","doi":"10.1109/MILCOM.2001.985993","DOIUrl":"https://doi.org/10.1109/MILCOM.2001.985993","url":null,"abstract":"Mobile CDMA cellular networks for tactical applications require base-station mobility in order to provide communications on the move. Because of the mobility of the base stations and the lack of a high-speed wire-line network between base stations, handoff of mobiles among base stations is more difficult than in a commercial CDMA cellular network. In this paper, we examine the performance of the reverse links in a tactical CDMA cellular network using continuous transmission for packet data communications. In particular, we consider the effect of limited handoff capability on the reverse-link capacity of the network.","PeriodicalId":136537,"journal":{"name":"2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131009372","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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