This paper addresses the question whether decode-and-forward relaying protocols can beat transmit diversity with respect to ε-outage capacity. We derive expressions of ε-outage capacity for transmit diversity, decode-and-forward, selective decode-and-forward, and incremental decode-and-forward. We demonstrate that the relaying protocols outperform transmit diversity in certain regions. Decode-and-forward is beneficial over transmit diversity when the relay is located close to the source. For selective decode-and-forward to beat transmit diversity, the relay should be placed between the source and the destination, but not too close to the source. The best performance is achieved by incremental decode-and-forward. The region in which this scheme is beneficial over transmit diversity is large. Moreover, as the region becomes smaller, the outage probability for the source-destination link becomes larger.
{"title":"Do decode-and-forward relaying protocols beat transmit diversity?","authors":"T. Renk, H. Jaekel, F. Jondral, A. Goldsmith","doi":"10.1109/EW.2010.5483434","DOIUrl":"https://doi.org/10.1109/EW.2010.5483434","url":null,"abstract":"This paper addresses the question whether decode-and-forward relaying protocols can beat transmit diversity with respect to ε-outage capacity. We derive expressions of ε-outage capacity for transmit diversity, decode-and-forward, selective decode-and-forward, and incremental decode-and-forward. We demonstrate that the relaying protocols outperform transmit diversity in certain regions. Decode-and-forward is beneficial over transmit diversity when the relay is located close to the source. For selective decode-and-forward to beat transmit diversity, the relay should be placed between the source and the destination, but not too close to the source. The best performance is achieved by incremental decode-and-forward. The region in which this scheme is beneficial over transmit diversity is large. Moreover, as the region becomes smaller, the outage probability for the source-destination link becomes larger.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133602423","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}
New advanced transmission protocols are required to fulfill the cost-efficiency objective of next generation mobile communications systems. This paper presents the study and performance evaluation of a two-relay assisted cooperative transmission protocol which could make a good candidate technique to improve the capacity and the quality of service of future cellular networks. Simulation results obtained in a realistic radio environment confirm the superior efficiency of this protocol over both its non-cooperative counterpart and conventional direct transmission, provided that the relays' positions are adequately chosen and that an interference cancellation mechanism is implemented in one of the two relays.
{"title":"Performance analysis of a two-relay assisted transmission scheme","authors":"Pascale Fouillot, I. Icart, C. L. Le Martret","doi":"10.1109/EW.2010.5483404","DOIUrl":"https://doi.org/10.1109/EW.2010.5483404","url":null,"abstract":"New advanced transmission protocols are required to fulfill the cost-efficiency objective of next generation mobile communications systems. This paper presents the study and performance evaluation of a two-relay assisted cooperative transmission protocol which could make a good candidate technique to improve the capacity and the quality of service of future cellular networks. Simulation results obtained in a realistic radio environment confirm the superior efficiency of this protocol over both its non-cooperative counterpart and conventional direct transmission, provided that the relays' positions are adequately chosen and that an interference cancellation mechanism is implemented in one of the two relays.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134182123","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}
Graphic Processing Units (GPUs) have evolved to provide a massive computational power. In contrast to Central Processing Units, GPUs are so-called many-core processors with hundreds of cores capable of running thousands of threads in parallel. This parallel processing power can accelerate the simulation of communication systems. In this work, we utilize NVIDIA's Compute Unified Device Architecture (CUDA) to execute two different sphere decoders on a graphic card. Both flat fading and frequency selective channels are considered. We find that the execution of the soft-sphere decoder can be accelerated by factors of 6-8, and the fixed-complexity sphere decoder even by a factor of 50.
{"title":"Boosting sphere decoding speed through Graphic Processing Units","authors":"M. S. Khairy, C. Mehlführer, M. Rupp","doi":"10.1109/EW.2010.5483399","DOIUrl":"https://doi.org/10.1109/EW.2010.5483399","url":null,"abstract":"Graphic Processing Units (GPUs) have evolved to provide a massive computational power. In contrast to Central Processing Units, GPUs are so-called many-core processors with hundreds of cores capable of running thousands of threads in parallel. This parallel processing power can accelerate the simulation of communication systems. In this work, we utilize NVIDIA's Compute Unified Device Architecture (CUDA) to execute two different sphere decoders on a graphic card. Both flat fading and frequency selective channels are considered. We find that the execution of the soft-sphere decoder can be accelerated by factors of 6-8, and the fixed-complexity sphere decoder even by a factor of 50.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"1 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134467224","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}
Luca Anchora, Luca Casone, Giovanni Ciccarese, M. De Blasi, P. Marra, Cosimo Palazzo
A number of Intelligent Flooding Schemes have been recently proposed in order to optimize message dissemination in Vehicular Ad Hoc Networks. In this paper we focus on a scheme which exploits a distributed timer-based contention mechanism for allowing only contention winners to forward the message and to suppress other potential forwarders. In particular, at each hop along the message propagation direction, potential forwarders wait for a time which is inversely proportional to their distance from the sender before rebroadcasting the packet; a potential forwarder is suppressed if it intercepts the packet rebroadcasted by another node during the waiting time. Performance of the scheme, in terms of message delivery ratio, delay and channel utilization, depends on the maximum waiting time (MaxWT) and on the maximum distance R allowed between the sender and a potential forwarder. This research work aims at evaluating an optimal setting of these parameters. We show that, although the values of MaxWT and R which maximize performance vary with traffic load and vehicle density, a dynamic algorithm is not essential. Then, we report how to set the values of the parameters to achieve a performance that is acceptable in the scenarios which we have considered.
{"title":"An optimal setting for the parameters of an Intelligent Flooding Scheme in VANETs","authors":"Luca Anchora, Luca Casone, Giovanni Ciccarese, M. De Blasi, P. Marra, Cosimo Palazzo","doi":"10.1109/EW.2010.5483439","DOIUrl":"https://doi.org/10.1109/EW.2010.5483439","url":null,"abstract":"A number of Intelligent Flooding Schemes have been recently proposed in order to optimize message dissemination in Vehicular Ad Hoc Networks. In this paper we focus on a scheme which exploits a distributed timer-based contention mechanism for allowing only contention winners to forward the message and to suppress other potential forwarders. In particular, at each hop along the message propagation direction, potential forwarders wait for a time which is inversely proportional to their distance from the sender before rebroadcasting the packet; a potential forwarder is suppressed if it intercepts the packet rebroadcasted by another node during the waiting time. Performance of the scheme, in terms of message delivery ratio, delay and channel utilization, depends on the maximum waiting time (MaxWT) and on the maximum distance R allowed between the sender and a potential forwarder. This research work aims at evaluating an optimal setting of these parameters. We show that, although the values of MaxWT and R which maximize performance vary with traffic load and vehicle density, a dynamic algorithm is not essential. Then, we report how to set the values of the parameters to achieve a performance that is acceptable in the scenarios which we have considered.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124288376","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}
The widespread use of heterogeneous wireless technologies, their integration and existence of multi-mode terminals enable users get associated to the best available networks according to user preferences over different application specific requirements, prices and network technologies. In this paper we present the user-centric interface selection decision, where negotiation between users and network operators is carried out using multi-attribute auctioning mechanism. We do not only consider the utility of users but also model the network operators' utility and discuss the truth telling behavior of network operators in terms of offered prices and service quality. The proposed approach builds on IEEE 802.21 standard. SIP and IPv6 based flow management approaches are discussed, the later approach is implemented using OPNET modeller simulator. The performance of our approach is compared with Long-term contractual approach in terms of users throughput, users' cost, operators' revenue and call blocking probability.
{"title":"Auction based interface selection with Media Independent Handover services and flow management","authors":"M. A. Khan, U. Toseef, Stefan Marx, C. Goerg","doi":"10.1109/EW.2010.5483497","DOIUrl":"https://doi.org/10.1109/EW.2010.5483497","url":null,"abstract":"The widespread use of heterogeneous wireless technologies, their integration and existence of multi-mode terminals enable users get associated to the best available networks according to user preferences over different application specific requirements, prices and network technologies. In this paper we present the user-centric interface selection decision, where negotiation between users and network operators is carried out using multi-attribute auctioning mechanism. We do not only consider the utility of users but also model the network operators' utility and discuss the truth telling behavior of network operators in terms of offered prices and service quality. The proposed approach builds on IEEE 802.21 standard. SIP and IPv6 based flow management approaches are discussed, the later approach is implemented using OPNET modeller simulator. The performance of our approach is compared with Long-term contractual approach in terms of users throughput, users' cost, operators' revenue and call blocking probability.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134450690","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}
Simulation and emulation are techniques frequently used for performance evaluation of wireless multi-hop networks. If the wireless devices are mobile, the movement patterns of these objects are found to have significant impact on the simulation and emulation results. This is obvious as the movements influence the topology of the network. In this paper, we focus on the sound performance evaluation of wireless multi-hop networks in tactical scenarios. In detail, we address the modeling of specific scenarios. We show the impact of proper modeling in disaster area and urban warfare scenarios. By doing so, we show how the tool BonnMotion can help other researchers in mobility dependent research.
{"title":"Evaluation of wireless multi-hop networks in tactical scenarios using BonnMotion","authors":"N. Aschenbruck, Raphael Ernst, P. Martini","doi":"10.1109/EW.2010.5483453","DOIUrl":"https://doi.org/10.1109/EW.2010.5483453","url":null,"abstract":"Simulation and emulation are techniques frequently used for performance evaluation of wireless multi-hop networks. If the wireless devices are mobile, the movement patterns of these objects are found to have significant impact on the simulation and emulation results. This is obvious as the movements influence the topology of the network. In this paper, we focus on the sound performance evaluation of wireless multi-hop networks in tactical scenarios. In detail, we address the modeling of specific scenarios. We show the impact of proper modeling in disaster area and urban warfare scenarios. By doing so, we show how the tool BonnMotion can help other researchers in mobility dependent research.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"183 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131867063","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}
Recursive Inverse (RI) adaptive filtering algorithm which uses a variable step-size and the instantaneous value of the autocorrelation matrix in the coefficient update equation was proposed in [1]. The algorithm was shown to have a higher performance compared with the RLS and RRLS algorithms. In this paper, a more efficient version with lower computational complexity is presented. The performance of the algorithm has been tested in a channel equalization setting and compared with those of the Recursive Least Squares (RLS) and Stabilized Fast Transversal Recursive Least Squares (SFTRLS) algorithms in Additive White Gaussian Noise (AWGN), Additive Correlated Gaussian Noise (ACGN), Additive White Impulsive Noise (AWIN) and Additive Correlated Impulsive Noise (ACIN) environments. Simulation results show that the Fast RI algorithm performs better than RLS and requires less computations. Additionally, the performance of the Fast RI algorithm is shown to be superior to that of the SFTRLS algorithm under the same conditions.
{"title":"An efficient Recursive Inverse adaptive filtering algorithm for channel equalization","authors":"Mohammad Shukri Ahmad, O. Kukrer, A. Hocanin","doi":"10.1109/EW.2010.5483397","DOIUrl":"https://doi.org/10.1109/EW.2010.5483397","url":null,"abstract":"Recursive Inverse (RI) adaptive filtering algorithm which uses a variable step-size and the instantaneous value of the autocorrelation matrix in the coefficient update equation was proposed in [1]. The algorithm was shown to have a higher performance compared with the RLS and RRLS algorithms. In this paper, a more efficient version with lower computational complexity is presented. The performance of the algorithm has been tested in a channel equalization setting and compared with those of the Recursive Least Squares (RLS) and Stabilized Fast Transversal Recursive Least Squares (SFTRLS) algorithms in Additive White Gaussian Noise (AWGN), Additive Correlated Gaussian Noise (ACGN), Additive White Impulsive Noise (AWIN) and Additive Correlated Impulsive Noise (ACIN) environments. Simulation results show that the Fast RI algorithm performs better than RLS and requires less computations. Additionally, the performance of the Fast RI algorithm is shown to be superior to that of the SFTRLS algorithm under the same conditions.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133158520","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}
Requirements for LTE-Advanced were defined in June 2008 and since then it has been developed and evaluated in 3GPP RAN Working Groups. LTE-Advanced Study Item is to be completed in March 2010 and several LTE Release 10 Work Items have already been kicked off. This paper addresses the state of LTE-Advanced standardization, performance and network deployments in February 2010.
{"title":"LTE-Advanced: The mainstream in mobile broadband evolution","authors":"Matti Kiiski","doi":"10.1109/EW.2010.5483512","DOIUrl":"https://doi.org/10.1109/EW.2010.5483512","url":null,"abstract":"Requirements for LTE-Advanced were defined in June 2008 and since then it has been developed and evaluated in 3GPP RAN Working Groups. LTE-Advanced Study Item is to be completed in March 2010 and several LTE Release 10 Work Items have already been kicked off. This paper addresses the state of LTE-Advanced standardization, performance and network deployments in February 2010.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121851025","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 mobile sink is widely considered to facilitate the data collection from energy constrained sensor fields, by having the sink come close to the sensors and conserving precious sensor node energy. The effectiveness of such a data collection approach can be measured in terms of the sensor energy conserved and the time required to collect the sensor data from the field (or, equivalently, the length of the trajectory implemented by the mobile sink). In this paper we explore two important dimensions in the design of mobile sink-based data collection schemes. One dimension refers to how close to the sensor nodes the sink moves to, to collect the data, which impacts on the transmission energy expenditure by the sensor node. The other dimension refers to the way the sink moves through the sensor field, to collect the data, which impacts on the delay in collecting the data. To capture the first dimension, the 0-hop and 1-hop data collection schemes are considered and studied; at the same time, two ”extreme” approaches to the sink mobility process are considered: a (topology unaware) random walk-based sink mobility scheme and a (topology aware, optimal) deterministic sink mobility scheme. Through the analytic and simulative study presented in this paper, an understanding of the level of the trade-offs involved between the energy spent by the sensor nodes and the delay in completing the data collection process is obtained.
{"title":"Sink mobility schemes for data extraction in large scale WSNs under single or zero hop data forwarding","authors":"Leonidas Tzevelekas, I. Stavrakakis","doi":"10.1109/EW.2010.5483528","DOIUrl":"https://doi.org/10.1109/EW.2010.5483528","url":null,"abstract":"A mobile sink is widely considered to facilitate the data collection from energy constrained sensor fields, by having the sink come close to the sensors and conserving precious sensor node energy. The effectiveness of such a data collection approach can be measured in terms of the sensor energy conserved and the time required to collect the sensor data from the field (or, equivalently, the length of the trajectory implemented by the mobile sink). In this paper we explore two important dimensions in the design of mobile sink-based data collection schemes. One dimension refers to how close to the sensor nodes the sink moves to, to collect the data, which impacts on the transmission energy expenditure by the sensor node. The other dimension refers to the way the sink moves through the sensor field, to collect the data, which impacts on the delay in collecting the data. To capture the first dimension, the 0-hop and 1-hop data collection schemes are considered and studied; at the same time, two ”extreme” approaches to the sink mobility process are considered: a (topology unaware) random walk-based sink mobility scheme and a (topology aware, optimal) deterministic sink mobility scheme. Through the analytic and simulative study presented in this paper, an understanding of the level of the trade-offs involved between the energy spent by the sensor nodes and the delay in completing the data collection process is obtained.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123702762","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}
Energy utilization is a challenging task that is being encountered in low-powered Wireless Sensor Networks (WSNs) when designing an algorithm, protocol or hardware. Congestion is a factor that can affect a network's lifetime (and energy utilization), since it usually leads to packet drops or collisions in the medium followed by possible retransmissions. Forwarding data packets through alternative paths is a way to counter congestion in WSNs. Proper node placement is essential to ensure good sensing coverage and communication connectivity. Node placement could also be affected by the need to create multiple routes to the sink; therefore, it can be proven vital for the improvement of energy utilization performance of this type of congestion control algorithms. In this paper we evaluate the energy utilization performance of HTAP (Hierarchical Tree Alternative Path) a congestion control and avoidance algorithm whose operation is based on a multipath routing scheme. HTAP energy utilization is evaluated under specific node placements and in correlation with a comparable routing scheme (Directed Diffusion). Through simulations, conclusions are extracted, suggesting node placements that assist in uniform and efficient energy utilization in WSNs.
在低功耗无线传感器网络(WSNs)中，当设计算法、协议或硬件时，能量利用是一个具有挑战性的任务。拥塞是一个可以影响网络生命周期(和能源利用)的因素，因为它通常会导致数据包丢失或介质中的冲突，随后可能会重传。通过备选路径转发数据包是解决无线传感器网络拥塞问题的一种方法。适当的节点放置对于确保良好的传感覆盖和通信连接至关重要。节点的位置也可能受到需要创建多个路由到接收器的影响;因此，提高这类拥塞控制算法的能量利用性能是至关重要的。本文对基于多路径路由方案的拥塞控制与避免算法HTAP (Hierarchical Tree Alternative Path)的能量利用性能进行了评价。HTAP能源利用在特定节点位置下进行评估，并与可比较的路由方案(定向扩散)相关。通过仿真，得出结论，建议节点放置有助于WSNs均匀有效地利用能量。
{"title":"Energy utilization of HTAP under specific node placements in Wireless Sensor Networks","authors":"Charalambos Sergiou, V. Vassiliou","doi":"10.1109/EW.2010.5483490","DOIUrl":"https://doi.org/10.1109/EW.2010.5483490","url":null,"abstract":"Energy utilization is a challenging task that is being encountered in low-powered Wireless Sensor Networks (WSNs) when designing an algorithm, protocol or hardware. Congestion is a factor that can affect a network's lifetime (and energy utilization), since it usually leads to packet drops or collisions in the medium followed by possible retransmissions. Forwarding data packets through alternative paths is a way to counter congestion in WSNs. Proper node placement is essential to ensure good sensing coverage and communication connectivity. Node placement could also be affected by the need to create multiple routes to the sink; therefore, it can be proven vital for the improvement of energy utilization performance of this type of congestion control algorithms. In this paper we evaluate the energy utilization performance of HTAP (Hierarchical Tree Alternative Path) a congestion control and avoidance algorithm whose operation is based on a multipath routing scheme. HTAP energy utilization is evaluated under specific node placements and in correlation with a comparable routing scheme (Directed Diffusion). Through simulations, conclusions are extracted, suggesting node placements that assist in uniform and efficient energy utilization in WSNs.","PeriodicalId":232165,"journal":{"name":"2010 European Wireless Conference (EW)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124438192","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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