Pub Date : 2005-11-28DOI: 10.1109/GLOCOM.2005.1578382
Junsung Kim, Minsu Shin, S. Shrestha, S. Chong
This paper focuses on low-power usages of mobile devices in WLAN (wireless local area network) environments. Recently, the researchers have been concentrating on power issues for long battery life. However, many of them consider only the MAC (medium access control) protocol. In this paper, we develop a resource allocation algorithm for low-power consumption without considering lower layer protocol. This algorithm provides fairness, efficiency and stability by using an optimization framework in mobile stations. We verify the efficiency of our algorithm by simulation using Intel Centrinotrade parameters, which shows the efficiency of our algorithm
{"title":"Energy-aware resource allocation in WLAN mobile devices","authors":"Junsung Kim, Minsu Shin, S. Shrestha, S. Chong","doi":"10.1109/GLOCOM.2005.1578382","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1578382","url":null,"abstract":"This paper focuses on low-power usages of mobile devices in WLAN (wireless local area network) environments. Recently, the researchers have been concentrating on power issues for long battery life. However, many of them consider only the MAC (medium access control) protocol. In this paper, we develop a resource allocation algorithm for low-power consumption without considering lower layer protocol. This algorithm provides fairness, efficiency and stability by using an optimization framework in mobile stations. We verify the efficiency of our algorithm by simulation using Intel Centrinotrade parameters, which shows the efficiency of our algorithm","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115191519","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 : 2005-11-28DOI: 10.1109/GLOCOM.2005.1578011
Sungchang Kim, B. Mukherjee, Minho Kang
Optical burst switching (OBS) is a promising solution to implement the optical Internet backbone. However, the lack of adequate congestion-control mechanisms may result in high burst loss. Schemes such as fiber delay line (FDL), wavelength conversion, and deflection routing to reduce burst collision are unable to prevent the network congestion effectively. To address this problem, we propose and investigate a global solution, called integrated congestion-control mechanism (ICCM), for OBS networks. ICCM, which combines congestion avoidance with recovery mechanism, restricts the amount of burst flows entering the network according to the feedback information from core routers to edge routers to prevent network congestion. Also, a flow-policing scheme is proposed to intentionally drop the overloaded traffic with a certain probability at a core router to support fairness among flows. Moreover, the transmission rate of each flow is controlled to achieve optimized performance such as maximizing throughput or minimizing loss probability using a two-step rate controller at the edge router. Simulation results show that ICCM effectively eliminates congestion within the network and that, when combined with a flow-policing mechanism, the fairness for competing flows can be supported while maintaining effective network performance
{"title":"Integrated congestion-control mechanism in optical burst switching networks","authors":"Sungchang Kim, B. Mukherjee, Minho Kang","doi":"10.1109/GLOCOM.2005.1578011","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1578011","url":null,"abstract":"Optical burst switching (OBS) is a promising solution to implement the optical Internet backbone. However, the lack of adequate congestion-control mechanisms may result in high burst loss. Schemes such as fiber delay line (FDL), wavelength conversion, and deflection routing to reduce burst collision are unable to prevent the network congestion effectively. To address this problem, we propose and investigate a global solution, called integrated congestion-control mechanism (ICCM), for OBS networks. ICCM, which combines congestion avoidance with recovery mechanism, restricts the amount of burst flows entering the network according to the feedback information from core routers to edge routers to prevent network congestion. Also, a flow-policing scheme is proposed to intentionally drop the overloaded traffic with a certain probability at a core router to support fairness among flows. Moreover, the transmission rate of each flow is controlled to achieve optimized performance such as maximizing throughput or minimizing loss probability using a two-step rate controller at the edge router. Simulation results show that ICCM effectively eliminates congestion within the network and that, when combined with a flow-policing mechanism, the fairness for competing flows can be supported while maintaining effective network performance","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"612 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123265590","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 : 2005-11-28DOI: 10.1109/GLOCOM.2005.1577908
Wan Choi, J. Andrews, R. Heath
Improving downlink CDMA capacity has been an area of intensive research for the past decade, especially as the downlink has become the capacity limiting link. Multi-antenna technologies are an obvious candidate for increasing the downlink capacity, but successfully decoding spatially multiplexed signals is very challenging in an interference-limited environment, such as that of CDMA cellular systems. In this paper, a simple and novel MIMO-CDMA system design is developed, in which users are assigned to a transmit antenna either without regard to channel knowledge (static) or based on antenna selection feedback bits (dynamic). These proposed antenna partitioning techniques have a minimal increase in complexity and require only small changes to existing CDMA standards. The outage probability and capacity of the proposed systems are derived and it is shown that they outperform conventional CDMA systems regardless of the number of antennas or antenna partitioning technique.
{"title":"Antenna partitioning for multiuser MIMO-CDMA","authors":"Wan Choi, J. Andrews, R. Heath","doi":"10.1109/GLOCOM.2005.1577908","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1577908","url":null,"abstract":"Improving downlink CDMA capacity has been an area of intensive research for the past decade, especially as the downlink has become the capacity limiting link. Multi-antenna technologies are an obvious candidate for increasing the downlink capacity, but successfully decoding spatially multiplexed signals is very challenging in an interference-limited environment, such as that of CDMA cellular systems. In this paper, a simple and novel MIMO-CDMA system design is developed, in which users are assigned to a transmit antenna either without regard to channel knowledge (static) or based on antenna selection feedback bits (dynamic). These proposed antenna partitioning techniques have a minimal increase in complexity and require only small changes to existing CDMA standards. The outage probability and capacity of the proposed systems are derived and it is shown that they outperform conventional CDMA systems regardless of the number of antennas or antenna partitioning technique.","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126143777","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 : 2005-11-28DOI: 10.1109/GLOCOM.2005.1577774
D. Magoni, P. Lorenz
A growing number of applications create overlays on top of the Internet. Several unsolved issues at the network layer can explain this trend to implement network services such as multicast, mobility and security at the application layer. However overlays require some form of internal addressing, routing and naming. Therefore their topologies are usually kept simple but this limits their flexibility and scalability. Our aim is to design an efficient and robust addressing, routing and naming framework for complex overlays. Our only assumption is that they are constrained by the Internet topology. Applications using our framework will be relieved from managing their own overlay topologies. This paper presents our framework in detail as well as some performance results concerning its routing efficiency, its reliability to network dynamics and its naming scalability.
{"title":"Application layer addressing, routing and naming framework for overlays","authors":"D. Magoni, P. Lorenz","doi":"10.1109/GLOCOM.2005.1577774","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1577774","url":null,"abstract":"A growing number of applications create overlays on top of the Internet. Several unsolved issues at the network layer can explain this trend to implement network services such as multicast, mobility and security at the application layer. However overlays require some form of internal addressing, routing and naming. Therefore their topologies are usually kept simple but this limits their flexibility and scalability. Our aim is to design an efficient and robust addressing, routing and naming framework for complex overlays. Our only assumption is that they are constrained by the Internet topology. Applications using our framework will be relieved from managing their own overlay topologies. This paper presents our framework in detail as well as some performance results concerning its routing efficiency, its reliability to network dynamics and its naming scalability.","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129051145","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 : 2005-11-28DOI: 10.1109/GLOCOM.2005.1577834
D. Divsalar, Christopher R. Jones, S. Dolinar, J. Thorpe
We propose several LDPC code constructions that simultaneously achieve good threshold and error floor performance. Minimum distance is shown to grow linearly with block size (similar to regular codes of variable degree at least 3) by considering ensemble average weight enumerators. Our constructions are based on projected graph, or protograph, structures that support high-speed decoder implementations. As with irregular ensembles, our constructions are sensitive to the proportion of degree-2 variable nodes. A code with too few such nodes tends to have an iterative decoding threshold that is far from the capacity threshold. A code with too many such nodes tends to not exhibit a minimum distance that grows linearly in block length. In this paper we also show that preceding can be used to lower the threshold of regular LDPC codes. The decoding thresholds of the proposed codes, which have linearly increasing minimum distance in block size, outperform that of regular LDPC codes. Furthermore, a family of low to high rate codes, with thresholds that adhere closely to their respective channel capacity thresholds, is presented. Simulation results for a few example codes show that the proposed codes have low error floors as well as good threshold SNR performance.
{"title":"Protograph based LDPC codes with minimum distance linearly growing with block size","authors":"D. Divsalar, Christopher R. Jones, S. Dolinar, J. Thorpe","doi":"10.1109/GLOCOM.2005.1577834","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1577834","url":null,"abstract":"We propose several LDPC code constructions that simultaneously achieve good threshold and error floor performance. Minimum distance is shown to grow linearly with block size (similar to regular codes of variable degree at least 3) by considering ensemble average weight enumerators. Our constructions are based on projected graph, or protograph, structures that support high-speed decoder implementations. As with irregular ensembles, our constructions are sensitive to the proportion of degree-2 variable nodes. A code with too few such nodes tends to have an iterative decoding threshold that is far from the capacity threshold. A code with too many such nodes tends to not exhibit a minimum distance that grows linearly in block length. In this paper we also show that preceding can be used to lower the threshold of regular LDPC codes. The decoding thresholds of the proposed codes, which have linearly increasing minimum distance in block size, outperform that of regular LDPC codes. Furthermore, a family of low to high rate codes, with thresholds that adhere closely to their respective channel capacity thresholds, is presented. Simulation results for a few example codes show that the proposed codes have low error floors as well as good threshold SNR performance.","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131579733","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 : 2005-11-28DOI: 10.1109/GLOCOM.2005.1578340
S. Kim, E. Y. Kim
We present the optimal Rake finger selection criterion that minimizes the a posteriori probability of symbol error in space-time block coded code division multiple access (CDMA) systems. It can serve as a benchmark for the performance of all a posteriori Rake finger selection criteria. Then we present suboptimal, but more practical, finger selection criteria based on a posteriori symbol error probability bounds, and analyze the bit error probability as a function of constellation sizes and number of resolvable paths. Simulation results show that there is a significant gain over the traditional signal strength-based selection criterion
{"title":"A posteriori Rake finger selection in space-time coded CDMA systems","authors":"S. Kim, E. Y. Kim","doi":"10.1109/GLOCOM.2005.1578340","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1578340","url":null,"abstract":"We present the optimal Rake finger selection criterion that minimizes the a posteriori probability of symbol error in space-time block coded code division multiple access (CDMA) systems. It can serve as a benchmark for the performance of all a posteriori Rake finger selection criteria. Then we present suboptimal, but more practical, finger selection criteria based on a posteriori symbol error probability bounds, and analyze the bit error probability as a function of constellation sizes and number of resolvable paths. Simulation results show that there is a significant gain over the traditional signal strength-based selection criterion","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115502922","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 : 2005-11-14DOI: 10.1109/GLOCOM.2005.1578212
K. Hamdi, L. Pap, E. Alsusa
This paper presents new accurate packet error rate analysis of ALOHA type networks that employ BPSK or QPSK modulation in a Rayleigh fading environment. Relying on a precise interference model, we derive new accurate expressions for the packet success probabilities that account for bit to bit error dependence, and are valid for unequal power levels. The accuracy of the new expressions is validated by simulation. These results are used to investigate the throughput performance of Aloha type networks in different local area environments
{"title":"Accurate evaluation of packet error probabilities considering bit-to-bit error dependence","authors":"K. Hamdi, L. Pap, E. Alsusa","doi":"10.1109/GLOCOM.2005.1578212","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1578212","url":null,"abstract":"This paper presents new accurate packet error rate analysis of ALOHA type networks that employ BPSK or QPSK modulation in a Rayleigh fading environment. Relying on a precise interference model, we derive new accurate expressions for the packet success probabilities that account for bit to bit error dependence, and are valid for unequal power levels. The accuracy of the new expressions is validated by simulation. These results are used to investigate the throughput performance of Aloha type networks in different local area environments","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"528 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116487114","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 : 2005-11-01DOI: 10.1109/GLOCOM.2005.1577378
Yuanbin Guo, D. McCain
In this paper, we present a reduced QRD-M matrix symbol detector in MIMO-OFDM systems. The QRD-M algorithm first decomposes the MIMO channel matrix into upper triangular matrix and applies a limited tree search to approximate the maximum-likelihood detector. The metric update is reduced from O(4.5 MC) to O(1.5 MC) by extracting the commonality. We then propose a partial quick-sort procedure and an embedded insert sort to achieve almost linear sorting. In the second part, we present efficient VLSI architectures utilizing the parallelism between subcarriers and design the pipelining in the multi-stage MIMO processing. The real-time architecture is implemented in an FPGA-based hardware accelerator with compact form factor, which achieves up to 100/spl times/ speedup in the simulation time.
{"title":"Reduced QRD-M detector in MIMO-OFDM systems with partial and embedded sorting","authors":"Yuanbin Guo, D. McCain","doi":"10.1109/GLOCOM.2005.1577378","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1577378","url":null,"abstract":"In this paper, we present a reduced QRD-M matrix symbol detector in MIMO-OFDM systems. The QRD-M algorithm first decomposes the MIMO channel matrix into upper triangular matrix and applies a limited tree search to approximate the maximum-likelihood detector. The metric update is reduced from O(4.5 MC) to O(1.5 MC) by extracting the commonality. We then propose a partial quick-sort procedure and an embedded insert sort to achieve almost linear sorting. In the second part, we present efficient VLSI architectures utilizing the parallelism between subcarriers and design the pipelining in the multi-stage MIMO processing. The real-time architecture is implemented in an FPGA-based hardware accelerator with compact form factor, which achieves up to 100/spl times/ speedup in the simulation time.","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116777085","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 : 2005-11-01DOI: 10.1109/GLOCOM.2005.1578367
F. Horlin, Stefaan De Rore, Eduardo Lopez-Estraviz, F. Naessens, L. Perre
New air interfaces are currently being developed to meet the high requirements of the emerging wireless communication systems. In this context, MC-CDMA is seen as a promising candidate for the 4G cellular communication systems since it can interestingly deal with the multipath propagation. The goal of this paper is to evaluate the impact of the carrier frequency offset, the sampling clock offset and IQ imbalance on the MC-CDMA downlink system performance, considering a receiver based on channel tracking designed to cope with high mobility conditions. It is demonstrated that part of the effects is compensated by the channel estimation and an expression of the variance of the remaining error is provided. For the setup considered in this paper, mostly IQ imbalance degrades the performance. On the other hand, the impact of sample clock offset is negligible with respect to the one of carrier frequency offset
{"title":"MC-CDMA performance in the presence of carrier frequency offset, sample clock offset and IQ imbalance","authors":"F. Horlin, Stefaan De Rore, Eduardo Lopez-Estraviz, F. Naessens, L. Perre","doi":"10.1109/GLOCOM.2005.1578367","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1578367","url":null,"abstract":"New air interfaces are currently being developed to meet the high requirements of the emerging wireless communication systems. In this context, MC-CDMA is seen as a promising candidate for the 4G cellular communication systems since it can interestingly deal with the multipath propagation. The goal of this paper is to evaluate the impact of the carrier frequency offset, the sampling clock offset and IQ imbalance on the MC-CDMA downlink system performance, considering a receiver based on channel tracking designed to cope with high mobility conditions. It is demonstrated that part of the effects is compensated by the channel estimation and an expression of the variance of the remaining error is provided. For the setup considered in this paper, mostly IQ imbalance degrades the performance. On the other hand, the impact of sample clock offset is negligible with respect to the one of carrier frequency offset","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121380751","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 : 2005-11-01DOI: 10.1109/GLOCOM.2005.1578319
A. Sadek, Zhu Han, K. Liu
It is of great importance for service providers to improve the coverage area without cost of more infrastructure in wireless networks especially in rural areas. Recently, cooperative communication has brought a new communication paradigm. In this paper, multi-node cooperative resource allocation is studied to schedule the transmission time slots so as to maximize the network overall rate (or the coverage area) under the quality of services constraints. To optimize the performance, first, the performance of the multi-node cooperative transmission is analyzed. Then a protocol is constructed between the mobiles and the base station for the resource allocation. From the simulation results, the proposed scheme can increase the user's rate by 5% for large cell sizes and improve the coverage by 180%, compared with the traditional scheme without cooperative transmission
{"title":"Multi-node cooperative resource allocation to improve coverage area in wireless networks","authors":"A. Sadek, Zhu Han, K. Liu","doi":"10.1109/GLOCOM.2005.1578319","DOIUrl":"https://doi.org/10.1109/GLOCOM.2005.1578319","url":null,"abstract":"It is of great importance for service providers to improve the coverage area without cost of more infrastructure in wireless networks especially in rural areas. Recently, cooperative communication has brought a new communication paradigm. In this paper, multi-node cooperative resource allocation is studied to schedule the transmission time slots so as to maximize the network overall rate (or the coverage area) under the quality of services constraints. To optimize the performance, first, the performance of the multi-node cooperative transmission is analyzed. Then a protocol is constructed between the mobiles and the base station for the resource allocation. From the simulation results, the proposed scheme can increase the user's rate by 5% for large cell sizes and improve the coverage by 180%, compared with the traditional scheme without cooperative transmission","PeriodicalId":319736,"journal":{"name":"GLOBECOM '05. IEEE Global Telecommunications Conference, 2005.","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127707567","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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