Pub Date : 2005-09-11DOI: 10.1109/PIMRC.2005.1651836
K. Ghaboosi, B. Khalaj
In this paper, by making slight modifications in protocol stack of wireless access points, the proposed CICADA scheme aims at isolating problems related to wireless section of a TCP connection from its wired portion, using IP spoofing and Virtual Protocol Stack scheme. As the simulation results for an 802.11 based system show, the proposed scheme improves the overall network throughput while reducing the mean and variance of end-to-end delay for voice and video flows due to smarter bandwidth allocation to elastic and real-time traffic. In addition, the proposed scheme uses a centralized NAT structure that prevents undesired disconnections during handovers and achieves a smaller handoff delay compared with other schemes. CICADA also improves the privacy of wireless sections by constructing virtual protocol stacks corresponding to mobile stations and using hierarchical two-level NAT structure in infrastructure networks in order to protect the distribution system against outside attacks
{"title":"A novel transport agent for wireless routers to improve TCP and UDP performance over wireless links","authors":"K. Ghaboosi, B. Khalaj","doi":"10.1109/PIMRC.2005.1651836","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651836","url":null,"abstract":"In this paper, by making slight modifications in protocol stack of wireless access points, the proposed CICADA scheme aims at isolating problems related to wireless section of a TCP connection from its wired portion, using IP spoofing and Virtual Protocol Stack scheme. As the simulation results for an 802.11 based system show, the proposed scheme improves the overall network throughput while reducing the mean and variance of end-to-end delay for voice and video flows due to smarter bandwidth allocation to elastic and real-time traffic. In addition, the proposed scheme uses a centralized NAT structure that prevents undesired disconnections during handovers and achieves a smaller handoff delay compared with other schemes. CICADA also improves the privacy of wireless sections by constructing virtual protocol stacks corresponding to mobile stations and using hierarchical two-level NAT structure in infrastructure networks in order to protect the distribution system against outside attacks","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115234376","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651461
Jaekwon Kim, Y. Lee, C. You, Dong-Ho Kim
In orthogonal frequency division multiple access (OFDMA) systems, the cyclic prefix (CP) length needs to be no less than the longest channel delay spread of many users, reducing bandwidth efficiency more significantly than in single user OFDM systems. We propose a novel receiver for OFDMA systems with an insufficient CP, exploiting the unused subchannels for a user. With the aid of computer simulations, we demonstrate that the proposed equalization method is superior to the conventional equalization method using a time domain channel shortening filter in terms of the achievable SNR and the error performance
{"title":"Equalization for OFDMA Systems Exploiting Unused Subchannels","authors":"Jaekwon Kim, Y. Lee, C. You, Dong-Ho Kim","doi":"10.1109/PIMRC.2005.1651461","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651461","url":null,"abstract":"In orthogonal frequency division multiple access (OFDMA) systems, the cyclic prefix (CP) length needs to be no less than the longest channel delay spread of many users, reducing bandwidth efficiency more significantly than in single user OFDM systems. We propose a novel receiver for OFDMA systems with an insufficient CP, exploiting the unused subchannels for a user. With the aid of computer simulations, we demonstrate that the proposed equalization method is superior to the conventional equalization method using a time domain channel shortening filter in terms of the achievable SNR and the error performance","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115307218","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651400
Yi Wu, V. Lau
We give a new formulation of the problem of signal design based on the design criteria for trellis coded unitary space-time communication system. Two key differences in our approach from that of previous method are that we not only combine the constellation design and set partition process together, we also use directly the Chernoff bound of the pairwise probability of error as design metric, which is a better figure of merit than previously used chordal distance, for unitary constellation design. By novelty employing a theorem for the Clarke subdifferential of the sum of the k largest singular values of the unitary matrix, we present a numerical optimization procedure for finding good constellations and report the best signal constellations found. Simulation results show that these constellations improve significantly upon the previously used constellations of unitary space-time signals
{"title":"Optimal Constellations Design for Trellis Coded Unitary Space-Time Modulation","authors":"Yi Wu, V. Lau","doi":"10.1109/PIMRC.2005.1651400","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651400","url":null,"abstract":"We give a new formulation of the problem of signal design based on the design criteria for trellis coded unitary space-time communication system. Two key differences in our approach from that of previous method are that we not only combine the constellation design and set partition process together, we also use directly the Chernoff bound of the pairwise probability of error as design metric, which is a better figure of merit than previously used chordal distance, for unitary constellation design. By novelty employing a theorem for the Clarke subdifferential of the sum of the k largest singular values of the unitary matrix, we present a numerical optimization procedure for finding good constellations and report the best signal constellations found. Simulation results show that these constellations improve significantly upon the previously used constellations of unitary space-time signals","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123121128","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651937
F. Ono, H. Habuchi, T. Arai
In this paper, a code selecting/spacing ALOHA system is proposed. The proposed system not only use Nm spreading codes but also M time slots. The proposed system varies in packet size from KNm Tc to KMNmTc, where K is the number of symbols per packet and Tc is the chip duration. So, the length of the packet for the proposed system changes according to the source data although the message bits per packet are constant. The number of symbols per packet of the proposed system is smaller than that of the conventional direct sequence spread spectrum multiple access (DS/SSMA) ALOHA system. Therefore, the proposed system is expected for improving the throughput performance of the conventional DS/SSMA ALOHA system. In the result of the throughput performance evaluation on the additive white Gaussian noise (AWGN) channel, it is shown that the throughput performance of the proposed system is about 2 times higher than that of the DS/SSMA ALOHA system
{"title":"Novel code selecting/spacing ALOHA system","authors":"F. Ono, H. Habuchi, T. Arai","doi":"10.1109/PIMRC.2005.1651937","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651937","url":null,"abstract":"In this paper, a code selecting/spacing ALOHA system is proposed. The proposed system not only use Nm spreading codes but also M time slots. The proposed system varies in packet size from KNm Tc to KMNmTc, where K is the number of symbols per packet and Tc is the chip duration. So, the length of the packet for the proposed system changes according to the source data although the message bits per packet are constant. The number of symbols per packet of the proposed system is smaller than that of the conventional direct sequence spread spectrum multiple access (DS/SSMA) ALOHA system. Therefore, the proposed system is expected for improving the throughput performance of the conventional DS/SSMA ALOHA system. In the result of the throughput performance evaluation on the additive white Gaussian noise (AWGN) channel, it is shown that the throughput performance of the proposed system is about 2 times higher than that of the DS/SSMA ALOHA system","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114659073","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651898
H. H. El-Mora, A. Sheikh, A. Zerguine
Multiple access interference and near-far effect cause performance limitation in the conventional single-user detector used in direct sequence/code division multiple access (DS-CDMA)-systems. In this paper, we present a novel multiuser detector (MUD) based on the new heuristic algorithm known as particle swarm algorithm (MUDPSO). We evaluate the BER performance of the proposed algorithm, by means of Monte Carlo simulation technique, and compare it to the BER performances of both the matched filter detector and the decorrelator multiuser detectors. We show that the new algorithm outperforms the other two. Moreover, the performance under near-far scenario, the system capacity and the computational complexity of the proposed detector are also investigated
{"title":"Application of particle swarm optimization algorithm to multiuser detection in CDMA","authors":"H. H. El-Mora, A. Sheikh, A. Zerguine","doi":"10.1109/PIMRC.2005.1651898","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651898","url":null,"abstract":"Multiple access interference and near-far effect cause performance limitation in the conventional single-user detector used in direct sequence/code division multiple access (DS-CDMA)-systems. In this paper, we present a novel multiuser detector (MUD) based on the new heuristic algorithm known as particle swarm algorithm (MUDPSO). We evaluate the BER performance of the proposed algorithm, by means of Monte Carlo simulation technique, and compare it to the BER performances of both the matched filter detector and the decorrelator multiuser detectors. We show that the new algorithm outperforms the other two. Moreover, the performance under near-far scenario, the system capacity and the computational complexity of the proposed detector are also investigated","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114663485","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651768
K. Ntagkounakis, P. Dallas, B. Sharif
In time division duplex (TDD) fixed broadband wireless access networks, co-channel interference that arises from the correlation of downlink and uplink signals in different sectors may considerably degrade the spectral efficiency. To overcome the complexity and costs of complete frame-TDD boundary synchronization in the network, a combined channel assignment (CA) and antenna array (AA) approach is proposed to mitigate interference. First a rotated-interleaved CA (RICA) scheme is applied, which exploits sector antenna directivity to reject the majority of interferers by receiving them through the antenna side and back lobes. Combined with RICA, an AA system is used in the base station side to further reduce intersector interference during both transmission and reception phases. For the worst-case interference scenario an unsynchronized TDD scheme, the proposed methodology achieves a 51.5% improvement in the average channel capacity while it considerably improves the uplink availability. An advantage of this approach is that it considers only low-complexity AA system configurations, thereby optimizing the corresponding cost
{"title":"Interference mitigation in TDD fixed broadband wireless access using channel assignment and antenna arrays","authors":"K. Ntagkounakis, P. Dallas, B. Sharif","doi":"10.1109/PIMRC.2005.1651768","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651768","url":null,"abstract":"In time division duplex (TDD) fixed broadband wireless access networks, co-channel interference that arises from the correlation of downlink and uplink signals in different sectors may considerably degrade the spectral efficiency. To overcome the complexity and costs of complete frame-TDD boundary synchronization in the network, a combined channel assignment (CA) and antenna array (AA) approach is proposed to mitigate interference. First a rotated-interleaved CA (RICA) scheme is applied, which exploits sector antenna directivity to reject the majority of interferers by receiving them through the antenna side and back lobes. Combined with RICA, an AA system is used in the base station side to further reduce intersector interference during both transmission and reception phases. For the worst-case interference scenario an unsynchronized TDD scheme, the proposed methodology achieves a 51.5% improvement in the average channel capacity while it considerably improves the uplink availability. An advantage of this approach is that it considers only low-complexity AA system configurations, thereby optimizing the corresponding cost","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114670491","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651413
A. Logothetis, A. Osseiran, P. Zetterberg
In this paper, single carrier frequency domain equalization with space time transmit diversity was implemented and evaluated in real-time using a DSP-based wireless MIMO test-bed. The implemented schemes supported a large set of modulations, from BPSK up to QAM64. Zero padding is introduced to mitigate inter-block interference. Robust time and frequency synchronization together with channel estimation based on Kalman filtering is used to address the adverse intersymbol interference and the severe carrier frequency offset due to hardware impairments
{"title":"Single Carrier Frequency Domain Equalization on a Real-Time DSP-Based MIMO Test-Bed","authors":"A. Logothetis, A. Osseiran, P. Zetterberg","doi":"10.1109/PIMRC.2005.1651413","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651413","url":null,"abstract":"In this paper, single carrier frequency domain equalization with space time transmit diversity was implemented and evaluated in real-time using a DSP-based wireless MIMO test-bed. The implemented schemes supported a large set of modulations, from BPSK up to QAM64. Zero padding is introduced to mitigate inter-block interference. Robust time and frequency synchronization together with channel estimation based on Kalman filtering is used to address the adverse intersymbol interference and the severe carrier frequency offset due to hardware impairments","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114673890","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651489
H. Claussen
For simulating mobility of both user terminals and base stations in wireless access systems, it is often advantageous to generate environment "maps" of the channel attenuations including path loss and shadow fading. However, the generation of a large number of spatially correlated shadow fading values, using for example the Cholesky decomposition of the corresponding correlation matrix, is computationally complex and requires a large amount of memory. In this paper an efficient low complexity alternative is proposed, where each new fading value is generated based only on the correlation with selected neighbouring values in the map. This results in a significant reduction of the computational complexity and memory requirements. It is shown that taking a small number of neighbouring values into account is sufficient to achieve relatively small correlation errors in the generated shadow fading maps
{"title":"Efficient modelling of channel maps with correlated shadow fading in mobile radio systems","authors":"H. Claussen","doi":"10.1109/PIMRC.2005.1651489","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651489","url":null,"abstract":"For simulating mobility of both user terminals and base stations in wireless access systems, it is often advantageous to generate environment \"maps\" of the channel attenuations including path loss and shadow fading. However, the generation of a large number of spatially correlated shadow fading values, using for example the Cholesky decomposition of the corresponding correlation matrix, is computationally complex and requires a large amount of memory. In this paper an efficient low complexity alternative is proposed, where each new fading value is generated based only on the correlation with selected neighbouring values in the map. This results in a significant reduction of the computational complexity and memory requirements. It is shown that taking a small number of neighbouring values into account is sufficient to achieve relatively small correlation errors in the generated shadow fading maps","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121376400","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651646
Zhuoqun Li, Lingfen Sun, E. Ifeachor
Service discovery is a challenging task in mobile ad-hoc networks which are characterized by their dynamic, infrastructure-less and bandwidth-limited nature. The goal of this paper is to develop a bandwidth efficient approach for service discovery in mobile ad-hoc networks. The main contribution of this paper is a novel track-based hybrid service discovery scheme. The proposed scheme performs service discovery based on the one dimensional proactive structure (e.g. tracks), instead of the existing two dimensional proactive structures (e.g. zones). This scheme can lead to reduced proactive traffic due to its light-weight organization of the hybrid structure. The density of proactive tracks is adapted to network traffic pattern dynamically for less proactive traffic. We simulated the Track-based approach in ns-2 network simulator with various network scales and mobility, and compared the performance with pure reactive (e.g. flooding) and Zone-based hybrid (e.g. bordercasting) protocols. Preliminary results show that, the track:-based approach achieved better efficient trade-offs between control packet overhead and querying success rate with minimal proactive costs among all the approaches compared
{"title":"Track-based hybrid service discovery in mobile ad-hoc networks","authors":"Zhuoqun Li, Lingfen Sun, E. Ifeachor","doi":"10.1109/PIMRC.2005.1651646","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651646","url":null,"abstract":"Service discovery is a challenging task in mobile ad-hoc networks which are characterized by their dynamic, infrastructure-less and bandwidth-limited nature. The goal of this paper is to develop a bandwidth efficient approach for service discovery in mobile ad-hoc networks. The main contribution of this paper is a novel track-based hybrid service discovery scheme. The proposed scheme performs service discovery based on the one dimensional proactive structure (e.g. tracks), instead of the existing two dimensional proactive structures (e.g. zones). This scheme can lead to reduced proactive traffic due to its light-weight organization of the hybrid structure. The density of proactive tracks is adapted to network traffic pattern dynamically for less proactive traffic. We simulated the Track-based approach in ns-2 network simulator with various network scales and mobility, and compared the performance with pure reactive (e.g. flooding) and Zone-based hybrid (e.g. bordercasting) protocols. Preliminary results show that, the track:-based approach achieved better efficient trade-offs between control packet overhead and querying success rate with minimal proactive costs among all the approaches compared","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124837777","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651718
A. Kusuda, Koji Yamamoto, S. Yoshida
Much recent interest has focused on applying multihop relaying to conventional cellular communication systems. Multihop relaying can broaden the cell coverage and enhance the capacity of cellular systems. However, as is well-known, cell coverage can also be broadened simply by lowering the transmission rate in a conventional cellular system. According to this commonality, we theoretically formulate the performance of cellular systems with multihop relaying in terms of outage probability and spectral efficiency using the same methodology to formulate the performance of cellular systems with rate adaptation. Simulation results reveal that multihop relaying and rate adaptation have very similar effects on the performance of cellular systems
{"title":"Performance comparison of multihop relaying and rate adaptation in cellular communication systems","authors":"A. Kusuda, Koji Yamamoto, S. Yoshida","doi":"10.1109/PIMRC.2005.1651718","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651718","url":null,"abstract":"Much recent interest has focused on applying multihop relaying to conventional cellular communication systems. Multihop relaying can broaden the cell coverage and enhance the capacity of cellular systems. However, as is well-known, cell coverage can also be broadened simply by lowering the transmission rate in a conventional cellular system. According to this commonality, we theoretically formulate the performance of cellular systems with multihop relaying in terms of outage probability and spectral efficiency using the same methodology to formulate the performance of cellular systems with rate adaptation. Simulation results reveal that multihop relaying and rate adaptation have very similar effects on the performance of cellular systems","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126146591","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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