Pub Date : 2011-11-01DOI: 10.1109/IWCLD.2011.6123077
S. Wendt, A. Samhat, Fabio Di Renzo
We investigate in this paper the resource allocation in wireless multi-hop network and we propose a cross layer based scheduling that takes into account the efficiency of advanced (smart) antenna techniques to increase network capacity by maximizing the number of concurrent transmissions without increasing interference. The proposed algorithm is applied to a WiMAX multi-hop network simulated using OPNET. The simulation results show the capability to dynamically adapt routing decision and scheduling according to the physical layer feedback while satisfying QoS criteria, in addition to a fair distribution of network traffic over whole links among nodes.
{"title":"Cross-layer resource allocation in WiMAX multi-hop networks using smart antennas","authors":"S. Wendt, A. Samhat, Fabio Di Renzo","doi":"10.1109/IWCLD.2011.6123077","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123077","url":null,"abstract":"We investigate in this paper the resource allocation in wireless multi-hop network and we propose a cross layer based scheduling that takes into account the efficiency of advanced (smart) antenna techniques to increase network capacity by maximizing the number of concurrent transmissions without increasing interference. The proposed algorithm is applied to a WiMAX multi-hop network simulated using OPNET. The simulation results show the capability to dynamically adapt routing decision and scheduling according to the physical layer feedback while satisfying QoS criteria, in addition to a fair distribution of network traffic over whole links among nodes.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129361596","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123084
James H. Martin, L. Dooley, K. Wong
Conventional single layer processing in Cognitive Radio Networks (CRN) can incur significant time costs in transferring information between the various layers of the Open System Interconnection (OSI) model, due its innate sequential structure. This is especially a problem for CRN which usually only has a narrow time window to access spectral gaps of either licensed or other secondary users (SU). To exploit this opportunity, cross layer processing (CLP) paradigms that share information between OSI layers and the radio system have been proposed to maximise throughput for SU, while maintaining Quality of Service (QoS) provision to the licensed primary user. With the global transference of TV systems to digital platforms, regulatory bodies have identified an opportunity to allocate additional digital TV (DTV) channels to CRNs on a localised basis, in what is called TV White Space (TVWS). This paper investigates how CLP of information can be effectively exploited to enhance CRN system performance by making key channel allocations to minimise disruption to the spectrum environment, while maximising available resources to fulfil application and network requirements within TVWS.
{"title":"A new cross-layer design strategy for TV White Space Cognitive Radio applications","authors":"James H. Martin, L. Dooley, K. Wong","doi":"10.1109/IWCLD.2011.6123084","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123084","url":null,"abstract":"Conventional single layer processing in Cognitive Radio Networks (CRN) can incur significant time costs in transferring information between the various layers of the Open System Interconnection (OSI) model, due its innate sequential structure. This is especially a problem for CRN which usually only has a narrow time window to access spectral gaps of either licensed or other secondary users (SU). To exploit this opportunity, cross layer processing (CLP) paradigms that share information between OSI layers and the radio system have been proposed to maximise throughput for SU, while maintaining Quality of Service (QoS) provision to the licensed primary user. With the global transference of TV systems to digital platforms, regulatory bodies have identified an opportunity to allocate additional digital TV (DTV) channels to CRNs on a localised basis, in what is called TV White Space (TVWS). This paper investigates how CLP of information can be effectively exploited to enhance CRN system performance by making key channel allocations to minimise disruption to the spectrum environment, while maximising available resources to fulfil application and network requirements within TVWS.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130032105","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123076
Mohamad Maaz, P. Mary, M. Hélard
Relay-assisted communication is a promising technique to increase the efficiency of future cellular systems. In this paper, we deal with resource allocations in relay-assisted OFDMA downlink communications. Our purpose is to find the optimal power, subcarrier and relay allocation maximizing the global data rate while keeping a low starvation rate, under heterogeneous data rate constraints among the users. A global algorithm jointly allocating the power, subcarriers and relays is first proposed. The achievable data rate is investigated as well as the average starvation rate in the network when the load, i.e. the number of active users in the network, is increasing. Our algorithm is compared to the existing literature by means of extensive simulation settings.
{"title":"Resource allocation for QoS aware relay-assisted OFDMA cellular networks","authors":"Mohamad Maaz, P. Mary, M. Hélard","doi":"10.1109/IWCLD.2011.6123076","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123076","url":null,"abstract":"Relay-assisted communication is a promising technique to increase the efficiency of future cellular systems. In this paper, we deal with resource allocations in relay-assisted OFDMA downlink communications. Our purpose is to find the optimal power, subcarrier and relay allocation maximizing the global data rate while keeping a low starvation rate, under heterogeneous data rate constraints among the users. A global algorithm jointly allocating the power, subcarriers and relays is first proposed. The achievable data rate is investigated as well as the average starvation rate in the network when the load, i.e. the number of active users in the network, is increasing. Our algorithm is compared to the existing literature by means of extensive simulation settings.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134428641","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123075
Sébastien Marcille, P. Ciblat, C. L. Le Martret
Hybrid ARQ (HARQ) schemes operate at the PHY and Medium Access (MAC) layers and their performance have been naturally studied at the MAC level. However, all the modern systems are going to be running under the IP protocol. Therefore, in order to get realistic performance of the whole system considering the multiple layer stacks, performance analysis at the IP layer is crucial. Very little work has been done so far in this direction, except in [2] which studies the delay statistics of IP packets with Selective-Repeat ARQ, and [1] which proposes a cross-layer optimization strategy between MAC and IP layers for ARQ, and in [8], [9] which consider the HARQ case. In this paper, we study the effect of erroneous feedbacks at the MAC layer on the performance at the IP layer considering both conventional HARQ schemes as well as the cross-layer strategy mentioned above. We derive in closed-form expressions the performance in terms of packet error rate (PER), efficiency, and delay with respect to the error probability of the feedback channel.
{"title":"Performance computation of cross-layer Hybrid ARQ schemes at IP layer in the presence of corrupted acknowledgments","authors":"Sébastien Marcille, P. Ciblat, C. L. Le Martret","doi":"10.1109/IWCLD.2011.6123075","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123075","url":null,"abstract":"Hybrid ARQ (HARQ) schemes operate at the PHY and Medium Access (MAC) layers and their performance have been naturally studied at the MAC level. However, all the modern systems are going to be running under the IP protocol. Therefore, in order to get realistic performance of the whole system considering the multiple layer stacks, performance analysis at the IP layer is crucial. Very little work has been done so far in this direction, except in [2] which studies the delay statistics of IP packets with Selective-Repeat ARQ, and [1] which proposes a cross-layer optimization strategy between MAC and IP layers for ARQ, and in [8], [9] which consider the HARQ case. In this paper, we study the effect of erroneous feedbacks at the MAC layer on the performance at the IP layer considering both conventional HARQ schemes as well as the cross-layer strategy mentioned above. We derive in closed-form expressions the performance in terms of packet error rate (PER), efficiency, and delay with respect to the error probability of the feedback channel.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123870121","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123089
Nabih Alaoui, J. Cances, V. Meghdadi
Optimizing architecture of sensor networks is a current topic of research. This research field can be applied in several contexts such as environmental monitoring or body area network. Performance improvement in terms of bit error rate is a major challenge. Reducing processing time and simplifying the operations of the network are the two main key points to be improved. A number of architectures have been designed to optimize the BER at destination. These architectures are mainly based on the LDPC codes (Low Density Parity Check) which have the disadvantage of the floor effect. The challenge is to find an optimal distribution of links between the sensors and relays to optimize the matrix H of the dual code and to avoid this floor effect. In this paper, we propose and simulate an efficient architecture for sensor network in a quasi-static Rayleigh fading channel environment. The new main idea is to enable communications between relays. Simulation results clearly show that the floor effect is significantly reduced with this kind of architecture.
{"title":"Efficient architecture design for mobile sensor networks","authors":"Nabih Alaoui, J. Cances, V. Meghdadi","doi":"10.1109/IWCLD.2011.6123089","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123089","url":null,"abstract":"Optimizing architecture of sensor networks is a current topic of research. This research field can be applied in several contexts such as environmental monitoring or body area network. Performance improvement in terms of bit error rate is a major challenge. Reducing processing time and simplifying the operations of the network are the two main key points to be improved. A number of architectures have been designed to optimize the BER at destination. These architectures are mainly based on the LDPC codes (Low Density Parity Check) which have the disadvantage of the floor effect. The challenge is to find an optimal distribution of links between the sensors and relays to optimize the matrix H of the dual code and to avoid this floor effect. In this paper, we propose and simulate an efficient architecture for sensor network in a quasi-static Rayleigh fading channel environment. The new main idea is to enable communications between relays. Simulation results clearly show that the floor effect is significantly reduced with this kind of architecture.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"195 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126502786","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123068
Zheng Chang, T. Ristaniemi
This paper considers a wireless cooperative OFDMA network with a base station and some relays. The relays adopt the decode-and-forward protocol and can assist the transmission from base station to mobile stations. The objective is to maximize the system transmission rate of downlink under various constraints. The optimal solution for such radio resource allocation problem has high computational complexity. Thus we divide our solution scheme into three steps. The first step is to select the relay that can achieve best transmission rate. Then the subcarrier is distributed to the selected relays. For each hop, the same subcarrier should not be used. Next, power allocation is adopted under the individual power constraints for each node. Simulation studies are conducted to evaluate the system performance. It confirms that our proposed algorithm can enhance the performance compared with newly proposed resource allocation schemes.
{"title":"Radio resource allocation for cooperative relay-assisted OFDMA wireless networks","authors":"Zheng Chang, T. Ristaniemi","doi":"10.1109/IWCLD.2011.6123068","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123068","url":null,"abstract":"This paper considers a wireless cooperative OFDMA network with a base station and some relays. The relays adopt the decode-and-forward protocol and can assist the transmission from base station to mobile stations. The objective is to maximize the system transmission rate of downlink under various constraints. The optimal solution for such radio resource allocation problem has high computational complexity. Thus we divide our solution scheme into three steps. The first step is to select the relay that can achieve best transmission rate. Then the subcarrier is distributed to the selected relays. For each hop, the same subcarrier should not be used. Next, power allocation is adopted under the individual power constraints for each node. Simulation studies are conducted to evaluate the system performance. It confirms that our proposed algorithm can enhance the performance compared with newly proposed resource allocation schemes.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121286905","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123088
I. Atanasov, D. Marinska, E. Pencheva
The paper investigates an approach to exchange quality of service information across the layers between third party applications and network functions for bearer resource management. The focus is on Parlay X Web Services which may be used to access functions for policy and charging control in all IP-based multimedia networks. A functional mapping of Parlay X interfaces onto network control protocol is suggested. The Parlay X Gateway utilization is evaluated taking into account as its distributed architecture, as the processing of both requests and notifications of events, concerning QoS management.
本文研究了一种用于承载资源管理的第三方应用程序和网络功能之间跨层交换服务质量信息的方法。重点是Parlay X Web Services，它可用于访问所有基于ip的多媒体网络中的策略和收费控制功能。提出了Parlay X接口到网络控制协议的功能映射。Parlay X网关的利用率评估考虑到它的分布式架构，作为请求和事件通知的处理，涉及QoS管理。
{"title":"Open service access in cross layer design","authors":"I. Atanasov, D. Marinska, E. Pencheva","doi":"10.1109/IWCLD.2011.6123088","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123088","url":null,"abstract":"The paper investigates an approach to exchange quality of service information across the layers between third party applications and network functions for bearer resource management. The focus is on Parlay X Web Services which may be used to access functions for policy and charging control in all IP-based multimedia networks. A functional mapping of Parlay X interfaces onto network control protocol is suggested. The Parlay X Gateway utilization is evaluated taking into account as its distributed architecture, as the processing of both requests and notifications of events, concerning QoS management.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127891805","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123087
V. Rodriguez
A wireless communication system work more efficiently if link-layer parameters such as modulation order, symbol rate and packet size are (adaptively) optimised. A common criterion is to maximise spectral efficiency subject to a very low bit-error constraint. But for systems equipped with strong error detection and a selective packet re-transmission mechanism, a packet-oriented criterion is more appropriate. Recently we showed that the link configuration that maximises bits per second or bits per Joule can be identified by drawing a tangent from the origin to the scaled graphs of the corresponding packet-success rate functions: the steeper the tangent the better the configuration. We now consider a tight symbol-rate constraint that forces the terminal to switch its configuration from the ideal as channel quality improves, and report on analytically-grounded performance experiments. A terminal with a flexible and unconstrained symbol rate enjoys a growing and overwhelming performance advantage over a similarly-endowed fixed-rate adaptive terminal. And the rate-flexible terminal retains a significant performance edge (up to 2-to-1) even when its symbol rate cannot exceed that of the fixed-rate terminal.
{"title":"Generalised link-layer optimisation: Application and performance evaluation","authors":"V. Rodriguez","doi":"10.1109/IWCLD.2011.6123087","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123087","url":null,"abstract":"A wireless communication system work more efficiently if link-layer parameters such as modulation order, symbol rate and packet size are (adaptively) optimised. A common criterion is to maximise spectral efficiency subject to a very low bit-error constraint. But for systems equipped with strong error detection and a selective packet re-transmission mechanism, a packet-oriented criterion is more appropriate. Recently we showed that the link configuration that maximises bits per second or bits per Joule can be identified by drawing a tangent from the origin to the scaled graphs of the corresponding packet-success rate functions: the steeper the tangent the better the configuration. We now consider a tight symbol-rate constraint that forces the terminal to switch its configuration from the ideal as channel quality improves, and report on analytically-grounded performance experiments. A terminal with a flexible and unconstrained symbol rate enjoys a growing and overwhelming performance advantage over a similarly-endowed fixed-rate adaptive terminal. And the rate-flexible terminal retains a significant performance edge (up to 2-to-1) even when its symbol rate cannot exceed that of the fixed-rate terminal.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130544592","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123073
Qing Bai, Jingrui Li, J. Nossek
We investigate the throughput maximizing data transmission strategy of an energy harvesting node which is able to harvest and store energy for communication. Solar cell and rechargeable battery technologies have made such nodes feasible. In addition to the energy arrival process and the battery capacity limitation, the energy consumption of the circuits of the node also plays an important role in the way how the harvested energy should be utilized. To this end, we assume for the transmitting node an active mode for which a constant circuit power is incurred, and a sleep mode for which no energy is consumed. The criteria that an optimal transmission strategy should satisfy are discussed, and based on them, a construction procedure of the optimal transmission strategy is proposed. Numerical simulations are performed to verify the theoretical results, and the impact of circuit power on the optimal transmission strategy and the maximal achievable throughput is studied.
{"title":"Throughput maximizing transmission strategy of energy harvesting nodes","authors":"Qing Bai, Jingrui Li, J. Nossek","doi":"10.1109/IWCLD.2011.6123073","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123073","url":null,"abstract":"We investigate the throughput maximizing data transmission strategy of an energy harvesting node which is able to harvest and store energy for communication. Solar cell and rechargeable battery technologies have made such nodes feasible. In addition to the energy arrival process and the battery capacity limitation, the energy consumption of the circuits of the node also plays an important role in the way how the harvested energy should be utilized. To this end, we assume for the transmitting node an active mode for which a constant circuit power is incurred, and a sleep mode for which no energy is consumed. The criteria that an optimal transmission strategy should satisfy are discussed, and based on them, a construction procedure of the optimal transmission strategy is proposed. Numerical simulations are performed to verify the theoretical results, and the impact of circuit power on the optimal transmission strategy and the maximal achievable throughput is studied.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114137326","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 : 2011-11-01DOI: 10.1109/IWCLD.2011.6123090
D. Quintas, V. Friderikos
Cross layer scheduling techniques rely on accurate system state information, in particular the channel state. Since effective link gains are inherently time-varying, scheduling decisions have to be made every time the channel changes and hence accurate channel state information must be collected. In this paper we propose scheduling techniques that are robust to channel variations, allowing less frequent schedule updates and reducing in that sense the communication overhead and improving the system performance. Lower bounds on the achieved goodput when robust scheduling is used, in single and multi hop networks, are derived and through simulation we study the trade-offs between data rates, robustness and energy consumption. Finally, it is shown that the price of robustness in relay-aided networks is less when compared to traditional architectures.
{"title":"Robust resource management for energy efficient cellular networks","authors":"D. Quintas, V. Friderikos","doi":"10.1109/IWCLD.2011.6123090","DOIUrl":"https://doi.org/10.1109/IWCLD.2011.6123090","url":null,"abstract":"Cross layer scheduling techniques rely on accurate system state information, in particular the channel state. Since effective link gains are inherently time-varying, scheduling decisions have to be made every time the channel changes and hence accurate channel state information must be collected. In this paper we propose scheduling techniques that are robust to channel variations, allowing less frequent schedule updates and reducing in that sense the communication overhead and improving the system performance. Lower bounds on the achieved goodput when robust scheduling is used, in single and multi hop networks, are derived and through simulation we study the trade-offs between data rates, robustness and energy consumption. Finally, it is shown that the price of robustness in relay-aided networks is less when compared to traditional architectures.","PeriodicalId":149596,"journal":{"name":"2011 Third International Workshop on Cross Layer Design","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117067489","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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