Pub Date : 2009-04-05DOI: 10.1109/WCNC.2009.4917743
Addisu Eshete, A. Arcia-Moret, David Ros, Yuming Jiang
The IEEE 802.16 is the standard for broadband wireless access. One promise of this technology (also called WiMAX) is to provide high-speed access to the Internet where the transmission control protocol (TCP) is the core transport protocol. In this paper, we study the impact of network asymmetry in WiMAX on TCP performance. In particular, we investigate the dependence of the aggregate throughput and goodput of TCP on factors such as frame duration, direction of flow, DL:UL ratio, modulation and coding schemes, and offered loads. We find that these factors affect TCP performance by exacerbating the network asymmetry inherent to the MAC layer.
{"title":"Impact of WiMAX Network Asymmetry on TCP","authors":"Addisu Eshete, A. Arcia-Moret, David Ros, Yuming Jiang","doi":"10.1109/WCNC.2009.4917743","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917743","url":null,"abstract":"The IEEE 802.16 is the standard for broadband wireless access. One promise of this technology (also called WiMAX) is to provide high-speed access to the Internet where the transmission control protocol (TCP) is the core transport protocol. In this paper, we study the impact of network asymmetry in WiMAX on TCP performance. In particular, we investigate the dependence of the aggregate throughput and goodput of TCP on factors such as frame duration, direction of flow, DL:UL ratio, modulation and coding schemes, and offered loads. We find that these factors affect TCP performance by exacerbating the network asymmetry inherent to the MAC layer.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128694125","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917909
F. Aloul, M. El-Tarhuni
In mobile radio communication systems using spread spectrum technology, an accurate estimate of the signal propagation delay is needed in order to recover the transmitted data. This process is usually done using a pseudo noise (PN) code acquisition algorithm to search for the correct propagation delay within a window of possible delays. In this paper, we propose a new approach to solving the PN code acquisition problem using advanced Boolean Satisfiability (SAT) techniques. SAT solvers use intelligent search algorithms that can traverse the search space and efficiently prune parts that contain no solutions. These solvers have recently been used to solve many challenging problems in Engineering and Computer Science. In this paper, we show how to formulate the PN code acquisition problem as a SAT instance and evaluate the use of advanced SAT techniques in solving the problem. Our approach is verified by simulation and presented results indicate that the proposed system achieves a detection probability for the correct delay of almost 100% for all practical cases.
{"title":"PN Code Acquisition Using Boolean Satisfiability Techniques","authors":"F. Aloul, M. El-Tarhuni","doi":"10.1109/WCNC.2009.4917909","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917909","url":null,"abstract":"In mobile radio communication systems using spread spectrum technology, an accurate estimate of the signal propagation delay is needed in order to recover the transmitted data. This process is usually done using a pseudo noise (PN) code acquisition algorithm to search for the correct propagation delay within a window of possible delays. In this paper, we propose a new approach to solving the PN code acquisition problem using advanced Boolean Satisfiability (SAT) techniques. SAT solvers use intelligent search algorithms that can traverse the search space and efficiently prune parts that contain no solutions. These solvers have recently been used to solve many challenging problems in Engineering and Computer Science. In this paper, we show how to formulate the PN code acquisition problem as a SAT instance and evaluate the use of advanced SAT techniques in solving the problem. Our approach is verified by simulation and presented results indicate that the proposed system achieves a detection probability for the correct delay of almost 100% for all practical cases.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128781647","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917826
F. Z. Yousaf, Alain Tigyo, C. Wietfeld
To manage the mobility of mobile networks, IETF has proposed MIPv6 based Network Mobility (NEMO) Basic Support protocol. However the NEMO protocol has severe performance limitations and does not specify the route optimization method for mobile networks and does not take into account the operational and functional complexities involving nested mobile networks. The Next Generation Network (NGN) however warrants and demands optimized protocol operation capabilities in terms of supporting nested mobile networks that would meet the stringent quality of service requirements imposed by NGN. This paper presents NERON: NEst Route Optimization for NEMO, an efficient and scalable approach that aims at enabling nodes behind nested mobile networks to use optimized communication paths with zero tunneling overhead and end-to-end delay, irrespective of the depth of the nest, with minimum changes to the base MIPv6 protocol and without introducing any new network entities. The performance results are validated using an accurate simulation model.
{"title":"NERON: A Route Optimization Scheme for Nested Mobile Networks","authors":"F. Z. Yousaf, Alain Tigyo, C. Wietfeld","doi":"10.1109/WCNC.2009.4917826","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917826","url":null,"abstract":"To manage the mobility of mobile networks, IETF has proposed MIPv6 based Network Mobility (NEMO) Basic Support protocol. However the NEMO protocol has severe performance limitations and does not specify the route optimization method for mobile networks and does not take into account the operational and functional complexities involving nested mobile networks. The Next Generation Network (NGN) however warrants and demands optimized protocol operation capabilities in terms of supporting nested mobile networks that would meet the stringent quality of service requirements imposed by NGN. \u0000 \u0000This paper presents NERON: NEst Route Optimization for NEMO, an efficient and scalable approach that aims at enabling nodes behind nested mobile networks to use optimized communication paths with zero tunneling overhead and end-to-end delay, irrespective of the depth of the nest, with minimum changes to the base MIPv6 protocol and without introducing any new network entities. The performance results are validated using an accurate simulation model.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"170 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128350834","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917987
Kun-Yi Tsai, Yung-Feng Lu, Ai-Chun Pang, Tei-Wei Kuo
With the popularity of VoIP, Push-To-Talk (PTT) services over the IP networks have gained their momentum. This research aims at essential design issues for the quality of service of PTT services. We explore the relationship between the speech quality and system design issues. MOS (Mean Opinion Score), which is raised by the ITU-T (International Telecommunication Union) as one of the most common benchmarks, is studied under factors in system designs and implementations. In particular, we focus on the analysis of packet delay, jitter, and packet loss for PTT services. Experiments are designed and executed with the considerations of PTT characteristics. Our goal is to provide more understanding of MOS versus PTT and deliver insights in future PTT system designs.
{"title":"The Speech Quality Analysis of Push-to-Talk Services","authors":"Kun-Yi Tsai, Yung-Feng Lu, Ai-Chun Pang, Tei-Wei Kuo","doi":"10.1109/WCNC.2009.4917987","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917987","url":null,"abstract":"With the popularity of VoIP, Push-To-Talk (PTT) services over the IP networks have gained their momentum. This research aims at essential design issues for the quality of service of PTT services. We explore the relationship between the speech quality and system design issues. MOS (Mean Opinion Score), which is raised by the ITU-T (International Telecommunication Union) as one of the most common benchmarks, is studied under factors in system designs and implementations. In particular, we focus on the analysis of packet delay, jitter, and packet loss for PTT services. Experiments are designed and executed with the considerations of PTT characteristics. Our goal is to provide more understanding of MOS versus PTT and deliver insights in future PTT system designs.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128996196","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917623
M. Lei, Ye Huang
The single-carrier block transmission (SCBT), a.k.a. single-carrier frequency-domain equalization (SC-FDE), is being considered as an option technique for the wireless personal area network (WPAN) operating at 60-GHz. To combat the inter-symbol interference (ISI) in non-line-of-sight (NLOS) environments, the frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion is much more effective than the one based on the zero forcing (ZF) criterion. However, MMSE-FDE needs the estimation of both the channel frequency response (CFR) and the signal-to-noise ratio (SNR). In this work, we estimated CFR and SNR based on the complementary Golay sequences whose sum auto-correlation has a unique peak and zero sidelobe. Through simulations, we proved that the proposed CFR and SNR estimation methods are very effective for SCBT system using MMSE-FDE.
{"title":"CFR and SNR Estimation Based on Complementary Golay Sequences for Single-Carrier Block Transmission in 60-GHz WPAN","authors":"M. Lei, Ye Huang","doi":"10.1109/WCNC.2009.4917623","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917623","url":null,"abstract":"The single-carrier block transmission (SCBT), a.k.a. single-carrier frequency-domain equalization (SC-FDE), is being considered as an option technique for the wireless personal area network (WPAN) operating at 60-GHz. To combat the inter-symbol interference (ISI) in non-line-of-sight (NLOS) environments, the frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion is much more effective than the one based on the zero forcing (ZF) criterion. However, MMSE-FDE needs the estimation of both the channel frequency response (CFR) and the signal-to-noise ratio (SNR). In this work, we estimated CFR and SNR based on the complementary Golay sequences whose sum auto-correlation has a unique peak and zero sidelobe. Through simulations, we proved that the proposed CFR and SNR estimation methods are very effective for SCBT system using MMSE-FDE.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130346580","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917690
H. Kang, H. Ryu, C. Kang
This paper introduces a notion of divide-by-K reuse strategy, which allows for K orthogonal chunks (subzones) of OFDMA data regions to be fully reused for all relay links throughout each cell in a N-hop relay-enhanced cellular TDD-OFDMA system with K ≤ N. Our objective is to configure a topology of relay stations subject to the divide-by-K reuse strategy, such that the end-to-end routes for relay stations are determined while maximizing the bandwidth efficiency of resource available for relay links. We propose a sub-optimal algorithm for a topology control that reduces co-channel interference while balancing the time-varying traffic load in a dynamical manner. Our system-level simulation results show that the average system throughput can be significantly improved by the proposed algorithm for the divide-by-K reuse strategy, especially with K = 3.
{"title":"Dynamic Topology Control for Multi-Hop Relaying in a Cellular TDD-OFDMA System","authors":"H. Kang, H. Ryu, C. Kang","doi":"10.1109/WCNC.2009.4917690","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917690","url":null,"abstract":"This paper introduces a notion of divide-by-K reuse strategy, which allows for K orthogonal chunks (subzones) of OFDMA data regions to be fully reused for all relay links throughout each cell in a N-hop relay-enhanced cellular TDD-OFDMA system with K ≤ N. Our objective is to configure a topology of relay stations subject to the divide-by-K reuse strategy, such that the end-to-end routes for relay stations are determined while maximizing the bandwidth efficiency of resource available for relay links. We propose a sub-optimal algorithm for a topology control that reduces co-channel interference while balancing the time-varying traffic load in a dynamical manner. Our system-level simulation results show that the average system throughput can be significantly improved by the proposed algorithm for the divide-by-K reuse strategy, especially with K = 3.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129116820","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917814
Rui Fa, R. D. Lamare
In this paper we propose a novel successive interference cancellation (SIC) strategy for multiple-input multiple-output (MIMO) spatial multiplexing systems based on multiple interference cancellation branches. The proposed detection structure employs SICs on several parallel branches which are equipped with different ordering patterns so that each branch produces a symbol estimate vector by exploiting a certain ordering pattern. The novel detector, therefore, achieves higher detection diversity by selecting the branch which yields the estimates with the best performance according to the selection rule. We consider three selection rules for the proposed detector, namely, maximum likelihood (ML), minimum mean square error (MMSE), constant modulus (CM) criteria. The simulation results reveal that our scheme successfully mitigates the error propagation and approaches the performance of the optimal ML detector, while requiring a significantly lower complexity than the ML detector.
{"title":"Multi-Branch Successive Interference Cancellation for MIMO Spatial Multiplexing Systems","authors":"Rui Fa, R. D. Lamare","doi":"10.1109/WCNC.2009.4917814","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917814","url":null,"abstract":"In this paper we propose a novel successive interference cancellation (SIC) strategy for multiple-input multiple-output (MIMO) spatial multiplexing systems based on multiple interference cancellation branches. The proposed detection structure employs SICs on several parallel branches which are equipped with different ordering patterns so that each branch produces a symbol estimate vector by exploiting a certain ordering pattern. The novel detector, therefore, achieves higher detection diversity by selecting the branch which yields the estimates with the best performance according to the selection rule. We consider three selection rules for the proposed detector, namely, maximum likelihood (ML), minimum mean square error (MMSE), constant modulus (CM) criteria. The simulation results reveal that our scheme successfully mitigates the error propagation and approaches the performance of the optimal ML detector, while requiring a significantly lower complexity than the ML detector.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129204013","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917992
J. Crichigno, Minyou Wu, W. Shu
Recent advances in the physical layer have enabled the simultaneous reception of multiple packets by a node in wireless networks. In this paper, we present a generalized model for the throughput optimization problem in wireless networks that support multi-packet reception (MPR) capability. Our model directly accounts for nodes with multiple transmitter antennas, which can be directional or omni-directional. We divide the problem into two subproblems: routing and scheduling. Due to the hardness of the scheduling subproblem, we propose a polynomial time heuristic based on a combination of greedy and linear programming paradigms. We use the devised scheme to study the impact of several design parameters on the performance of MPR-capable networks, including the number of interfaces, the beamwidth and the receiver range of the antennas. Numerical results demonstrate the effectiveness and the generality of the scheme, and permit us to draw valuable conclusions about MPR-capable networks.
{"title":"Throughput Optimization in Wireless Networks with Multi-Packet Reception and Directional Antennas","authors":"J. Crichigno, Minyou Wu, W. Shu","doi":"10.1109/WCNC.2009.4917992","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917992","url":null,"abstract":"Recent advances in the physical layer have enabled the simultaneous reception of multiple packets by a node in wireless networks. In this paper, we present a generalized model for the throughput optimization problem in wireless networks that support multi-packet reception (MPR) capability. Our model directly accounts for nodes with multiple transmitter antennas, which can be directional or omni-directional. We divide the problem into two subproblems: routing and scheduling. Due to the hardness of the scheduling subproblem, we propose a polynomial time heuristic based on a combination of greedy and linear programming paradigms. We use the devised scheme to study the impact of several design parameters on the performance of MPR-capable networks, including the number of interfaces, the beamwidth and the receiver range of the antennas. Numerical results demonstrate the effectiveness and the generality of the scheme, and permit us to draw valuable conclusions about MPR-capable networks.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130580047","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917608
Kun Cai, Xiao Li, Yik-Chung Wu
This paper addresses the problem of carrier frequency offset (CFO) estimation in orthogonal frequency division multiplexing (OFDM) systems using Bayesian method. Depending on the availability of the noise variance, two general CFO estimators are derived. Furthermore, the two general maximum a posteriori (MAP) estimators are developed into several special cases based on different degrees of prior information on parameters. The relationships between the proposed estimators and existing estimators are comprehensively investigated. Finally, numerical results demonstrate the effects of employing different prior information on the estimation performances.
{"title":"Bayesian CFO Estimation in OFDM Systems","authors":"Kun Cai, Xiao Li, Yik-Chung Wu","doi":"10.1109/WCNC.2009.4917608","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917608","url":null,"abstract":"This paper addresses the problem of carrier frequency offset (CFO) estimation in orthogonal frequency division multiplexing (OFDM) systems using Bayesian method. Depending on the availability of the noise variance, two general CFO estimators are derived. Furthermore, the two general maximum a posteriori (MAP) estimators are developed into several special cases based on different degrees of prior information on parameters. The relationships between the proposed estimators and existing estimators are comprehensively investigated. Finally, numerical results demonstrate the effects of employing different prior information on the estimation performances.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123196772","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 : 2009-04-05DOI: 10.1109/WCNC.2009.4917631
V. Y. Zhang, A. Wong
In this paper, a novel nonlinear programming (NLP) approach for non-line-of-sight (NLOS) localization in severe multipath environments is proposed. It leverages on the bidirectional estimation of the Angle of Arrival (AOA) and the Time of Arrival (TOA) of signals between the mobile station (MS) and the reference stations (RSs), and has the ability to work with just two paths. Basic Approach (BA) and Extended Approach (EA) are addressed, and the latter employs a simple method to identify one-bound path with high probability. Simulation results illustrate that the proposed algorithm can improve the localization accuracy greatly, especially when only few one-bound scattering paths exist.
{"title":"Combined AOA and TOA NLOS Localization With Nonlinear Programming in Severe Multipath Environments","authors":"V. Y. Zhang, A. Wong","doi":"10.1109/WCNC.2009.4917631","DOIUrl":"https://doi.org/10.1109/WCNC.2009.4917631","url":null,"abstract":"In this paper, a novel nonlinear programming (NLP) approach for non-line-of-sight (NLOS) localization in severe multipath environments is proposed. It leverages on the bidirectional estimation of the Angle of Arrival (AOA) and the Time of Arrival (TOA) of signals between the mobile station (MS) and the reference stations (RSs), and has the ability to work with just two paths. Basic Approach (BA) and Extended Approach (EA) are addressed, and the latter employs a simple method to identify one-bound path with high probability. Simulation results illustrate that the proposed algorithm can improve the localization accuracy greatly, especially when only few one-bound scattering paths exist.","PeriodicalId":186150,"journal":{"name":"2009 IEEE Wireless Communications and Networking Conference","volume":"2010 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123226270","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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