Pub Date : 2009-10-08DOI: 10.1109/APCC.2009.5375499
Jun Zhang, Chao Zhang, Lei Wang, Guo Wei
An updatable Automatic Repeat reQuest (ARQ) protocol for distributed space-time coded cooperative networks is proposed in this paper. We define a decoding relay set (DS), composed of the relays decoding the packet from source correctly. The DS would be expanded as the round of ARQ increasing, because the relays failing to receive correct packet in previous (re)transmission are still possible to decode the packet successfully in future retransmission. Since more and more relays would participate in ARQ process, the possibility that the destination can decode the error-free packet would be improved. Simulation results show that the updatable protocol has a lower packet loss ratio (PLR) and smaller average number of retransmission (Naver) than conventional protocol. Especially, when the channels between relays are in good condition, the proposed protocol can obtain about 1.6dB gain at a PLR of 10−3.
{"title":"Updatable ARQ protocol for distributed space-time coded relay networks","authors":"Jun Zhang, Chao Zhang, Lei Wang, Guo Wei","doi":"10.1109/APCC.2009.5375499","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375499","url":null,"abstract":"An updatable Automatic Repeat reQuest (ARQ) protocol for distributed space-time coded cooperative networks is proposed in this paper. We define a decoding relay set (DS), composed of the relays decoding the packet from source correctly. The DS would be expanded as the round of ARQ increasing, because the relays failing to receive correct packet in previous (re)transmission are still possible to decode the packet successfully in future retransmission. Since more and more relays would participate in ARQ process, the possibility that the destination can decode the error-free packet would be improved. Simulation results show that the updatable protocol has a lower packet loss ratio (PLR) and smaller average number of retransmission (Naver) than conventional protocol. Especially, when the channels between relays are in good condition, the proposed protocol can obtain about 1.6dB gain at a PLR of 10−3.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126426926","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375695
Kaikai Chi, Xiaohong Jiang, Baoliu Ye, H. Y. Shwe, S. Horiguchi
In multihop wireless networks, many applications require end-to-end reliable multicast communication with 100% packet delivery ratio. Recently, network coding has been applied to the reliable link-level multicast in wireless networks, where multiple lost packets with distinct intended receivers are XOR-ed together as one packet and forwarded via single retransmission, resulting in a significant reduction of bandwidth consumption in the scenarios of many receivers. However, the simple XOR operation cannot fully exploit the potential coding opportunities. Moreover, for the reliable multicast in multihop wireless networks, the number of receivers of link-level multicast is usually not large and thus this coding-based link-level multicast cannot provide a promising gain. In this work, we propose a new network coding-based reliable multicast scheme which exploits both network coding and the physical-layer broadcast nature. Specifically, first, at each link-level multicast the source node performs the more general coding operations instead of XOR and conducts the random linear packet coding such that more coding gain can be achieved. Second, each node snoops on all communications over the wireless medium and stores the overheard packets for packet decoding, such that an additional coding gain can be obtained. Extensive simulations demonstrate that the proposed scheme can greatly improve the transmission efficiency, especially in the case of large-group multicast.
{"title":"Efficient network coding-based end-to-end reliable multicast in multi-hop wireless networks","authors":"Kaikai Chi, Xiaohong Jiang, Baoliu Ye, H. Y. Shwe, S. Horiguchi","doi":"10.1109/APCC.2009.5375695","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375695","url":null,"abstract":"In multihop wireless networks, many applications require end-to-end reliable multicast communication with 100% packet delivery ratio. Recently, network coding has been applied to the reliable link-level multicast in wireless networks, where multiple lost packets with distinct intended receivers are XOR-ed together as one packet and forwarded via single retransmission, resulting in a significant reduction of bandwidth consumption in the scenarios of many receivers. However, the simple XOR operation cannot fully exploit the potential coding opportunities. Moreover, for the reliable multicast in multihop wireless networks, the number of receivers of link-level multicast is usually not large and thus this coding-based link-level multicast cannot provide a promising gain. In this work, we propose a new network coding-based reliable multicast scheme which exploits both network coding and the physical-layer broadcast nature. Specifically, first, at each link-level multicast the source node performs the more general coding operations instead of XOR and conducts the random linear packet coding such that more coding gain can be achieved. Second, each node snoops on all communications over the wireless medium and stores the overheard packets for packet decoding, such that an additional coding gain can be obtained. Extensive simulations demonstrate that the proposed scheme can greatly improve the transmission efficiency, especially in the case of large-group multicast.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128917157","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375629
K. Shang, N. Jian, J. Ping, Xian Shi, Sujun Zhang, Jianguo Yan, Mingyuan Wang
Using the radio telescopes in Chinese VLBI Net (CVN) and the sampling board, we have developed algorithms that extract three-way Doppler information from the radio tracking data of Mars Express (MEX) — a Martian probe that belongs to European Space Agency (ESA). Our latest results indicate the accuracy of three-way Doppler is about 1mm/s in 1 second integration time, relative to an 8.4GHz carrier. The three-way Doppler data have been used in orbit determination of Mars Express.
{"title":"Three-way Doppler observation of Mars Express","authors":"K. Shang, N. Jian, J. Ping, Xian Shi, Sujun Zhang, Jianguo Yan, Mingyuan Wang","doi":"10.1109/APCC.2009.5375629","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375629","url":null,"abstract":"Using the radio telescopes in Chinese VLBI Net (CVN) and the sampling board, we have developed algorithms that extract three-way Doppler information from the radio tracking data of Mars Express (MEX) — a Martian probe that belongs to European Space Agency (ESA). Our latest results indicate the accuracy of three-way Doppler is about 1mm/s in 1 second integration time, relative to an 8.4GHz carrier. The three-way Doppler data have been used in orbit determination of Mars Express.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128993241","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375682
Jie Ding, Jiaming Guo, Daiming Qu, Tao Jiang
Spectrum sensing is a crucial technology for cognitive radio networks. In this paper, we develop a novel spectrum sensing method for secondary users to sense the idle spectrum. The key idea of the proposed method is combining multiple slots energy detection. Firstly, we establish the probability model regarding the appearance of the primary user at each slot of a secondary user slots window structure. Unlike the conventional scheme which allocates the same weight to each slot, we propose a probability-based scheme, in which the weight for each slot is based on the probability of the presence of the primary signals in the corresponding slot. Extensive simulation results show that the proposed scheme can offer better performance than that of the conventional scheme.
{"title":"Novel multiple slots energy detection for spectrum sensing in cognitive radio networks","authors":"Jie Ding, Jiaming Guo, Daiming Qu, Tao Jiang","doi":"10.1109/APCC.2009.5375682","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375682","url":null,"abstract":"Spectrum sensing is a crucial technology for cognitive radio networks. In this paper, we develop a novel spectrum sensing method for secondary users to sense the idle spectrum. The key idea of the proposed method is combining multiple slots energy detection. Firstly, we establish the probability model regarding the appearance of the primary user at each slot of a secondary user slots window structure. Unlike the conventional scheme which allocates the same weight to each slot, we propose a probability-based scheme, in which the weight for each slot is based on the probability of the presence of the primary signals in the corresponding slot. Extensive simulation results show that the proposed scheme can offer better performance than that of the conventional scheme.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127887595","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375591
Suyue Gao, Qingchun Chen, Jiaxiang Li, Zheng Ma, P. Fan
In this paper, two effective techniques are proposed to improve the computation efficiency of the sub-code constrained algorithm for the determination of free distance for Turbo codes. Firstly, it is known that, the determination of the minimum output Hamming weight of the recursive systematic convolutional (RSC) code under some input constraints is the crucial problem in the constrained sub-code algorithm towards the weight distribution calculation for Turbo codes. And the modified Viterbi algorithm was utilized to solve this problem. In this paper, the backward state transition based (BST) algorithm is introduced to determine the minimum output Hamming weight of the RSC codes for the given input constraints. Although the state transition-based calculation is utilized as well, it is shown that, by making full use of the state transition characteristics of the given RSC codes, multiple step calculations may be merged into one step calculation, thus improving the computation efficiency when determining the minimum output Hamming weight of the RSC code. Secondly, it is proposed to employ the backward computation procedure instead of the forward one when implementing the sub-code algorithm. And it is validated that, the proposed backward computation method could be utilized to speed up the determination of the free distance for Turbo codes. And the 3GPP standard Turbo code is used as an example to validate the applicability of the proposed improved schemes.
{"title":"On the improved sub-code constrained algorithm for the determination of free distance for turbo codes","authors":"Suyue Gao, Qingchun Chen, Jiaxiang Li, Zheng Ma, P. Fan","doi":"10.1109/APCC.2009.5375591","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375591","url":null,"abstract":"In this paper, two effective techniques are proposed to improve the computation efficiency of the sub-code constrained algorithm for the determination of free distance for Turbo codes. Firstly, it is known that, the determination of the minimum output Hamming weight of the recursive systematic convolutional (RSC) code under some input constraints is the crucial problem in the constrained sub-code algorithm towards the weight distribution calculation for Turbo codes. And the modified Viterbi algorithm was utilized to solve this problem. In this paper, the backward state transition based (BST) algorithm is introduced to determine the minimum output Hamming weight of the RSC codes for the given input constraints. Although the state transition-based calculation is utilized as well, it is shown that, by making full use of the state transition characteristics of the given RSC codes, multiple step calculations may be merged into one step calculation, thus improving the computation efficiency when determining the minimum output Hamming weight of the RSC code. Secondly, it is proposed to employ the backward computation procedure instead of the forward one when implementing the sub-code algorithm. And it is validated that, the proposed backward computation method could be utilized to speed up the determination of the free distance for Turbo codes. And the 3GPP standard Turbo code is used as an example to validate the applicability of the proposed improved schemes.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124547572","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375473
H. K. Maheshwari, A. Kemp, B. Peng
This paper compares methods of localization in order to try and reduce the processing overhead of optimal multi-lateration whilst still achieving close to its accuracy. Three methods of localization are examined, firstly optimal multi-lateration (OML), which provides the benchmark in terms of accuracy achievable. Secondly sub-optimal blind trilateration (SBT) which randomly selects the minimum feasible number of anchors. This defines the lower processing limit. Thirdly we compare these with modified sub-optimal blind trilateration (MSBT) which selects anchor nodes based on geometric dilution of precision (GDOP). Our analysis and results show that this method of anchor selection requires considerable additional processing but does provide good localization performance.
{"title":"Localization performance comparison using optimal and sub-optimal lateration in WSNs","authors":"H. K. Maheshwari, A. Kemp, B. Peng","doi":"10.1109/APCC.2009.5375473","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375473","url":null,"abstract":"This paper compares methods of localization in order to try and reduce the processing overhead of optimal multi-lateration whilst still achieving close to its accuracy. Three methods of localization are examined, firstly optimal multi-lateration (OML), which provides the benchmark in terms of accuracy achievable. Secondly sub-optimal blind trilateration (SBT) which randomly selects the minimum feasible number of anchors. This defines the lower processing limit. Thirdly we compare these with modified sub-optimal blind trilateration (MSBT) which selects anchor nodes based on geometric dilution of precision (GDOP). Our analysis and results show that this method of anchor selection requires considerable additional processing but does provide good localization performance.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124013493","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375698
Qi Zhang, Ju Liu, Peng Lan, Lei Chen
Transmit antenna shuffling (TAS) has been used widely in Double Space Time Transmit Diversity (DSTTD) systems for performance improvement. In this paper, an angle feedback and its feedback selection criterion applied in a space time coding scheme are proposed for DSTTD systems. Compared with the existing TAS scheme, according to the analysis of system, the proposed scheme has lower realization complexity. Simulations show that the proposed scheme with 2-bit angle feedback achieves almost the same performance of DSTTD systems with TAS scheme which requires 3-bit feedback.
{"title":"Performance of angle feedback vs. shuffling scheme for DSTTD systems","authors":"Qi Zhang, Ju Liu, Peng Lan, Lei Chen","doi":"10.1109/APCC.2009.5375698","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375698","url":null,"abstract":"Transmit antenna shuffling (TAS) has been used widely in Double Space Time Transmit Diversity (DSTTD) systems for performance improvement. In this paper, an angle feedback and its feedback selection criterion applied in a space time coding scheme are proposed for DSTTD systems. Compared with the existing TAS scheme, according to the analysis of system, the proposed scheme has lower realization complexity. Simulations show that the proposed scheme with 2-bit angle feedback achieves almost the same performance of DSTTD systems with TAS scheme which requires 3-bit feedback.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123019969","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375470
Zi Yun, Laixian Peng, Wendong Zhao, Chang Tian
CICQ(Combined Input-Crosspoint Queued) is a switch fabric with buffers in crosspoints, which brings its nice distributed parallel scheduling property with no internal speedup required. In order to adjust to the nonuniform traffic in the network environment, a novel round-robin scheduling algorithm by using the longest queue detecting (RR-LQD) is proposed. The simulation results show that the RR-LQD can achieve 100% throughput and delay performance close to LQF-RR under various uniform and non-uniform traffics. In addition, the time complexity of RR-LQD is O(1) for hardware implementation. The implementation feasibility of RR-LQD is shown by an FPGA-based design in this paper.
{"title":"RR-LQD: A novel scheduling algorithm for CICQ switching fabrics","authors":"Zi Yun, Laixian Peng, Wendong Zhao, Chang Tian","doi":"10.1109/APCC.2009.5375470","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375470","url":null,"abstract":"CICQ(Combined Input-Crosspoint Queued) is a switch fabric with buffers in crosspoints, which brings its nice distributed parallel scheduling property with no internal speedup required. In order to adjust to the nonuniform traffic in the network environment, a novel round-robin scheduling algorithm by using the longest queue detecting (RR-LQD) is proposed. The simulation results show that the RR-LQD can achieve 100% throughput and delay performance close to LQF-RR under various uniform and non-uniform traffics. In addition, the time complexity of RR-LQD is O(1) for hardware implementation. The implementation feasibility of RR-LQD is shown by an FPGA-based design in this paper.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131573014","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375671
Chin-Kuo Jao, Shyue-Win Wei
Carrier frequency offset (CFO) may cause multiple access interference (MAI) among users in multi-carrier code division multiple access (MC-CDMA) system. In the paper the code sensitivity of spreading codes and its correlative to the CFO is observed. An interesting property of orthogonality invariant for spreading codes under CFO has been presented. Based on the properties of code sensitivity, several algorithms of selecting the spread codes that will decrease the MAI caused by frequency offset are proposed. Using the presented code selection methods, the system capacity of MC-CDMA can be effectively increased without increasing the system complexity.
{"title":"Spreading code selection methods for MC-CDMA under carrier frequency offset","authors":"Chin-Kuo Jao, Shyue-Win Wei","doi":"10.1109/APCC.2009.5375671","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375671","url":null,"abstract":"Carrier frequency offset (CFO) may cause multiple access interference (MAI) among users in multi-carrier code division multiple access (MC-CDMA) system. In the paper the code sensitivity of spreading codes and its correlative to the CFO is observed. An interesting property of orthogonality invariant for spreading codes under CFO has been presented. Based on the properties of code sensitivity, several algorithms of selecting the spread codes that will decrease the MAI caused by frequency offset are proposed. Using the presented code selection methods, the system capacity of MC-CDMA can be effectively increased without increasing the system complexity.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130911187","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 : 2009-10-08DOI: 10.1109/APCC.2009.5375701
Hong-Yi Lin, Hsi-Pin Ma
This paper focuses on a Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Multiple (OFDM) system, which uses Space Frequency Block Coding (SFBC) and an intercarrier interference (ICI) estimation/mitigation module for high mobility environment. The proposed algorithm is with low complexity which is proportional to O(N) (instead of O(N3)) and flexibly to apply to Single Input Single Output (SISO)/MIMO systems. Simulation results affirm the theoretical analysis with an average of 3 dB gain improvement.
{"title":"An MIMO-OFDM baseband engine for high mobility environment","authors":"Hong-Yi Lin, Hsi-Pin Ma","doi":"10.1109/APCC.2009.5375701","DOIUrl":"https://doi.org/10.1109/APCC.2009.5375701","url":null,"abstract":"This paper focuses on a Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Multiple (OFDM) system, which uses Space Frequency Block Coding (SFBC) and an intercarrier interference (ICI) estimation/mitigation module for high mobility environment. The proposed algorithm is with low complexity which is proportional to O(N) (instead of O(N3)) and flexibly to apply to Single Input Single Output (SISO)/MIMO systems. Simulation results affirm the theoretical analysis with an average of 3 dB gain improvement.","PeriodicalId":217893,"journal":{"name":"2009 15th Asia-Pacific Conference on Communications","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131420323","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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