Streaming video has become a popular form of transferring video over wireless networks. TCP-friendly rate control (TFRC) is used as a streaming video transport protocol. Using both TCP congestion response function and current network conditions, TFRC adjusts its sending rate to yield the maximum TCP-friendly throughput. Since TFRC was designed for applications that would prefer to maintain a slowly-changing sending rate, it is less responsive to changes in handover between next-generation wireless overlay network. This paper shows a new TFRC method for vertical handover (VHO) over wireless overlay network. The proposed TFRC method uses explicit VHO messages for faster rate adaptation to a new target network. The simulation results show that the proposed one provides better QoS and throughput supports than the conventional TFRC scheme during VHO.
{"title":"TCP-Friendly Congestion Control for Streaming Video Service over Wireless Overlay Network","authors":"Jae-Young Pyun, Ho-Jin Choi","doi":"10.1109/ICCW.2008.14","DOIUrl":"https://doi.org/10.1109/ICCW.2008.14","url":null,"abstract":"Streaming video has become a popular form of transferring video over wireless networks. TCP-friendly rate control (TFRC) is used as a streaming video transport protocol. Using both TCP congestion response function and current network conditions, TFRC adjusts its sending rate to yield the maximum TCP-friendly throughput. Since TFRC was designed for applications that would prefer to maintain a slowly-changing sending rate, it is less responsive to changes in handover between next-generation wireless overlay network. This paper shows a new TFRC method for vertical handover (VHO) over wireless overlay network. The proposed TFRC method uses explicit VHO messages for faster rate adaptation to a new target network. The simulation results show that the proposed one provides better QoS and throughput supports than the conventional TFRC scheme during VHO.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115285982","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}
A novel scheme for integrating Mobile IPv6 and Multiprotocol Label Switching (MPLS) named the Optimized Mobile MPLS (OMMPLS) is proposed. The aim of OMMPLS is to make the process of registration (or binding refresh) and Label Switching Path (LSP) setup (or maintenance) be carried out simultaneously to reduce the handover latency and signaling redundancy. To realize the aim, a new IPv6 Hop-by-Hop Options Header named the MPLS Header is defined, which includes some information about setting up or maintaining LSP. The MPLS Header is put in the Binding Update or the Binding Acknowledgement message of Mobile IPv6 protocol. When the network nodes receive such messages, they set up or maintain LSP in terms of MPLS Header. In addition, OMMPLS can integrate Hierarchical Mobile IPv6 naturally, thus realizing the fast re-building LSP after the mobile user roams into another subnet within a region. Analyses show that the handover latency and the LSP setup latency of OMMPLS are both smaller than those of the existing scheme, which means the optimization is realized.
{"title":"Optimized Mobile MPLS","authors":"Shengling Wang, Yong Cui, S. Das, Mingwei Xu","doi":"10.1109/ICCW.2008.89","DOIUrl":"https://doi.org/10.1109/ICCW.2008.89","url":null,"abstract":"A novel scheme for integrating Mobile IPv6 and Multiprotocol Label Switching (MPLS) named the Optimized Mobile MPLS (OMMPLS) is proposed. The aim of OMMPLS is to make the process of registration (or binding refresh) and Label Switching Path (LSP) setup (or maintenance) be carried out simultaneously to reduce the handover latency and signaling redundancy. To realize the aim, a new IPv6 Hop-by-Hop Options Header named the MPLS Header is defined, which includes some information about setting up or maintaining LSP. The MPLS Header is put in the Binding Update or the Binding Acknowledgement message of Mobile IPv6 protocol. When the network nodes receive such messages, they set up or maintain LSP in terms of MPLS Header. In addition, OMMPLS can integrate Hierarchical Mobile IPv6 naturally, thus realizing the fast re-building LSP after the mobile user roams into another subnet within a region. Analyses show that the handover latency and the LSP setup latency of OMMPLS are both smaller than those of the existing scheme, which means the optimization is realized.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117172770","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}
Fang Yang, Jintao Wang, Jun Wang, Jian Song, Zhixing Yang
Digital television/terrestrial multimedia broadcasting (DTMB), announced as the Chinese digital television terrestrial broadcasting (DTTB) standard in August, 2006, recommends three PN padding modes as guard intervals (GI) and training sequences for both multi- and single-carrier block transmissions. The conventional channel estimation methods can be performed through either the subtraction of the pseudo-noise (PN) sequence or the cancellation of residual inter-symbol interference, which are quite complex. In this paper, a simple method is introduced to separate the PN sequence from the OFDM symbol and the channel impulse response (CIR) estimation can be obtained and updated via the reconstruction of the PN sequence in an iterative manner. Analysis shows that the proposed algorithm achieves low-complexity channel estimation and can be applied to the DTMB receiver directly. Simulation shows that the proposed algorithm works well under slow-fading broadcast channel even with long delay spread.
{"title":"Channel Estimation for the Chinese DTTB System Based on a Novel Iterative PN Sequence Reconstruction","authors":"Fang Yang, Jintao Wang, Jun Wang, Jian Song, Zhixing Yang","doi":"10.1109/ICCW.2008.60","DOIUrl":"https://doi.org/10.1109/ICCW.2008.60","url":null,"abstract":"Digital television/terrestrial multimedia broadcasting (DTMB), announced as the Chinese digital television terrestrial broadcasting (DTTB) standard in August, 2006, recommends three PN padding modes as guard intervals (GI) and training sequences for both multi- and single-carrier block transmissions. The conventional channel estimation methods can be performed through either the subtraction of the pseudo-noise (PN) sequence or the cancellation of residual inter-symbol interference, which are quite complex. In this paper, a simple method is introduced to separate the PN sequence from the OFDM symbol and the channel impulse response (CIR) estimation can be obtained and updated via the reconstruction of the PN sequence in an iterative manner. Analysis shows that the proposed algorithm achieves low-complexity channel estimation and can be applied to the DTMB receiver directly. Simulation shows that the proposed algorithm works well under slow-fading broadcast channel even with long delay spread.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123525592","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}
We consider how two secondary users should interact to maximize their total throughput in a two- channel sensing-based opportunistic spectrum access network where spectrum opportunities are time varying and spatially inhomogeneous. By modeling the occupancy of the primary users as discrete-time Markov chains, we obtain the optimal dynamic coordination policy using a partially observable Markov decision process (POMDP) solver. We also develop several tractable approaches - a cooperative multiuser approach based on explicit communication between the secondary users, a learning-based approach involving use of collision feedback information, and a single-user approach based on uncooperative independent decisions. As a baseline we consider the static partitioning policy where both users are allocated a single channel of their own. Simulations comparing the performance of these strategies yield several interesting findings: that significant improvements over static partitioning are possible with the optimal scheme; that the cooperative multiuser approach shows near-optimal performance in all cases; that there are scenarios when learning through collision feedback can be beneficial; and that the single-user approach generally shows poor performance.
{"title":"Cooperation and Learning in Multiuser Opportunistic Spectrum Access","authors":"Hua Liu, B. Krishnamachari, Qing Zhao","doi":"10.1109/ICCW.2008.98","DOIUrl":"https://doi.org/10.1109/ICCW.2008.98","url":null,"abstract":"We consider how two secondary users should interact to maximize their total throughput in a two- channel sensing-based opportunistic spectrum access network where spectrum opportunities are time varying and spatially inhomogeneous. By modeling the occupancy of the primary users as discrete-time Markov chains, we obtain the optimal dynamic coordination policy using a partially observable Markov decision process (POMDP) solver. We also develop several tractable approaches - a cooperative multiuser approach based on explicit communication between the secondary users, a learning-based approach involving use of collision feedback information, and a single-user approach based on uncooperative independent decisions. As a baseline we consider the static partitioning policy where both users are allocated a single channel of their own. Simulations comparing the performance of these strategies yield several interesting findings: that significant improvements over static partitioning are possible with the optimal scheme; that the cooperative multiuser approach shows near-optimal performance in all cases; that there are scenarios when learning through collision feedback can be beneficial; and that the single-user approach generally shows poor performance.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126642572","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}
This paper deals with spectrum sensing for dynamic spectrum access (DSA) via channelized radiometers. Consecutive mean excision (CME) algorithms have been employed in the literature to identify the presence or absence of licensed user signals. To obtain better control of false-alarm rate and detection rate, an improved CME algorithm is proposed in this paper, in which two thresholds are incorporated to perform the channel cluster based licensed user signal detection. It is verified through numerical experiments that with appropriate compromise on setting the two thresholds, the improved CME algorithm can significantly boost the detection rate while ideally maintain the false-alarm rate as sufficiently low as desired.
{"title":"Improved Consecutive Mean Excision Algorithm Based Spectrum Sensing for Dynamic Spectrum Access","authors":"Bin Shen, K. Kwak, Longyang Huang, Zheng Zhou","doi":"10.1109/ICCW.2008.103","DOIUrl":"https://doi.org/10.1109/ICCW.2008.103","url":null,"abstract":"This paper deals with spectrum sensing for dynamic spectrum access (DSA) via channelized radiometers. Consecutive mean excision (CME) algorithms have been employed in the literature to identify the presence or absence of licensed user signals. To obtain better control of false-alarm rate and detection rate, an improved CME algorithm is proposed in this paper, in which two thresholds are incorporated to perform the channel cluster based licensed user signal detection. It is verified through numerical experiments that with appropriate compromise on setting the two thresholds, the improved CME algorithm can significantly boost the detection rate while ideally maintain the false-alarm rate as sufficiently low as desired.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115574896","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}
This paper investigates the radio resource allocation scheme for the uplink OFDMA systems and a new uplink-based radio resource allocation (URRA) algorithm is proposed based on the maximization of system throughput and the quality of service (QoS) constraints of the users. The URRA algorithm is composed of two parts. The first part introduces a dynamically priority parameter for each user according to the uplink channel state information (UCSI), the QoS constraints and data buffer information, and then allocates resources to meet the user's QoS constraints based on the priority parameters. The second part of the URRA algorithm allocates the remaining subcarriers to the users who have the most increment of throughput. Simulation results show that the URRA algorithm not only increases the system throughput performance subject to the QoS constraints, but also significantly reduces the computational complexity compared with the existing algorithm.
{"title":"Radio Resource Allocation Algorithm for the Uplink OFDMA System","authors":"Juncai Shi, A. Hu","doi":"10.1109/ICCW.2008.7","DOIUrl":"https://doi.org/10.1109/ICCW.2008.7","url":null,"abstract":"This paper investigates the radio resource allocation scheme for the uplink OFDMA systems and a new uplink-based radio resource allocation (URRA) algorithm is proposed based on the maximization of system throughput and the quality of service (QoS) constraints of the users. The URRA algorithm is composed of two parts. The first part introduces a dynamically priority parameter for each user according to the uplink channel state information (UCSI), the QoS constraints and data buffer information, and then allocates resources to meet the user's QoS constraints based on the priority parameters. The second part of the URRA algorithm allocates the remaining subcarriers to the users who have the most increment of throughput. Simulation results show that the URRA algorithm not only increases the system throughput performance subject to the QoS constraints, but also significantly reduces the computational complexity compared with the existing algorithm.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"199 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122557232","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}
Today's upper-class passenger cars have various interconnected electronic devices. Each device performs complex functions, enabled by software that can be stored in a flash memory. Of these, the devices in the multimedia and infotainment domain contain by far the most software with a size in the order of one Gbyte. In this domain, the devices are the performance bottlenecks, not the communication systems. Throughout the vehicle life cycle, parts of the software have to be frequently updated during maintenance. Today, the software of the devices is updated in a consecutive manner. Due to performance bottlenecks caused by the affected devices, the update can take a long time that leads to high costs. Therefore, the objective is to reduce the total update time by a higher utilization of the common bus resource. In this paper, we introduce and investigate algorithms that update the software of multiple devices simultaneously and evaluate the efficiency of these algorithms. We focus on scheduling algorithms on the Application layer and the logical link control (LLC) layer and model the update process by means of Petri nets. Our studies show that it is most promising to combine a simple scheduling algorithm on the Application layer with Round Robin on the LLC layer.
{"title":"Scheduling Algorithms for Simultaneous Software Updates of Electronic Devices in Vehicles","authors":"J. Sommer, V. Feil, E. Adeva Sanz","doi":"10.1109/ICCW.2008.80","DOIUrl":"https://doi.org/10.1109/ICCW.2008.80","url":null,"abstract":"Today's upper-class passenger cars have various interconnected electronic devices. Each device performs complex functions, enabled by software that can be stored in a flash memory. Of these, the devices in the multimedia and infotainment domain contain by far the most software with a size in the order of one Gbyte. In this domain, the devices are the performance bottlenecks, not the communication systems. Throughout the vehicle life cycle, parts of the software have to be frequently updated during maintenance. Today, the software of the devices is updated in a consecutive manner. Due to performance bottlenecks caused by the affected devices, the update can take a long time that leads to high costs. Therefore, the objective is to reduce the total update time by a higher utilization of the common bus resource. In this paper, we introduce and investigate algorithms that update the software of multiple devices simultaneously and evaluate the efficiency of these algorithms. We focus on scheduling algorithms on the Application layer and the logical link control (LLC) layer and model the update process by means of Petri nets. Our studies show that it is most promising to combine a simple scheduling algorithm on the Application layer with Round Robin on the LLC layer.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114183825","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}
Successful operation of a wireless personal area network utilizing cognitive radio technology requires accurate and timely sensing of the status of channels the network operates on. The performance of the sensing process in which the working set of N channels is sensed by randomly choosing X < N channels, is analyzed via two performance measures: the difference in the true number of free channels and the number viewed by the cognitive network, and the delay in detecting the activity changes on the channels from the working set. Our probabilistic analysis points to the range of values in which such, incomplete sensing is capable of maintaining an accurate view of the status of the working channel set.
{"title":"The Impact of Inaccurate Sensing Information in Cognitive Wireless Personal Area Networks","authors":"J. Misic, V. Mišić","doi":"10.1109/ICCW.2008.95","DOIUrl":"https://doi.org/10.1109/ICCW.2008.95","url":null,"abstract":"Successful operation of a wireless personal area network utilizing cognitive radio technology requires accurate and timely sensing of the status of channels the network operates on. The performance of the sensing process in which the working set of N channels is sensed by randomly choosing X < N channels, is analyzed via two performance measures: the difference in the true number of free channels and the number viewed by the cognitive network, and the delay in detecting the activity changes on the channels from the working set. Our probabilistic analysis points to the range of values in which such, incomplete sensing is capable of maintaining an accurate view of the status of the working channel set.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121390481","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}
Qiang Wu, Wanlun Zhao, P. Black, Y. Tokgoz, R. Padovani
Research and development on mobile phone positioning technologies are gaining momentum due to the potential in location based services. Mobile location is estimated based on measurements from satellites and terrestrial base stations. Satellite measurements often available in rural and suburban areas are less or not available in dense urban and indoor areas. Thus, base station measurements play an important role in mobile positioning. In this paper, we present the highly detectable pilot (HDP) that is being standardized in 3GPP2 for cdma2000 1xEV-DO. HDP allows mobile to detect significantly more base stations, and thus provides much better accuracy in location estimate.
{"title":"cdma2000 Highly Detectable Pilot","authors":"Qiang Wu, Wanlun Zhao, P. Black, Y. Tokgoz, R. Padovani","doi":"10.1109/ICCW.2008.8","DOIUrl":"https://doi.org/10.1109/ICCW.2008.8","url":null,"abstract":"Research and development on mobile phone positioning technologies are gaining momentum due to the potential in location based services. Mobile location is estimated based on measurements from satellites and terrestrial base stations. Satellite measurements often available in rural and suburban areas are less or not available in dense urban and indoor areas. Thus, base station measurements play an important role in mobile positioning. In this paper, we present the highly detectable pilot (HDP) that is being standardized in 3GPP2 for cdma2000 1xEV-DO. HDP allows mobile to detect significantly more base stations, and thus provides much better accuracy in location estimate.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114210378","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}
Wireless sensor networks (WSNs) usually have a high node density, which makes it unnecessary to require all nodes to be continually active. Scheduling different nodes to be awake at different times saves energy for WSNs. However, traditional scheduling algorithms do not consider the directional data traffic towards the sink and maintaining coverage of the entire network, making them fail to optimize the energy efficiency and the network performance. This paper proposes a clustering algorithm, which combines scheduling techniques, to split the network into clusters based on the geographical information of nodes and the directional data traffic. The clusters are organized in such a way that all clusters have similar lifetimes. Only one node in each cluster is scheduled to be active at any give time to monitor that cluster. Simulation results show that this algorithm not only improves energy efficiency for WSNs, but also improves the performance of delivering data to the sink.
{"title":"Geographical Information Based Clustering Algorithm to Equalize Cluster Lifetime throughout Wireless Sensor Networks","authors":"D. Wei, H. Chan, S. Kaplan","doi":"10.1109/ICCW.2008.47","DOIUrl":"https://doi.org/10.1109/ICCW.2008.47","url":null,"abstract":"Wireless sensor networks (WSNs) usually have a high node density, which makes it unnecessary to require all nodes to be continually active. Scheduling different nodes to be awake at different times saves energy for WSNs. However, traditional scheduling algorithms do not consider the directional data traffic towards the sink and maintaining coverage of the entire network, making them fail to optimize the energy efficiency and the network performance. This paper proposes a clustering algorithm, which combines scheduling techniques, to split the network into clusters based on the geographical information of nodes and the directional data traffic. The clusters are organized in such a way that all clusters have similar lifetimes. Only one node in each cluster is scheduled to be active at any give time to monitor that cluster. Simulation results show that this algorithm not only improves energy efficiency for WSNs, but also improves the performance of delivering data to the sink.","PeriodicalId":360127,"journal":{"name":"ICC Workshops - 2008 IEEE International Conference on Communications Workshops","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121617464","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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