Pub Date : 2010-05-23DOI: 10.1109/ICC.2010.5501830
Liwen Yu, L. Milstein, J. Proakis, B. Rao
We consider a convolutionally coded orthogonal frequency-division multiple access (OFDMA) based cognitive radio system where each user achieves perfect synchronization for its own signal, while different users are asynchronized due to random timing offsets. The presence of asynchronous secondary users introduces potential multiple access interference (MAI) to each primary user's receiver. The strength of the MAI is determined by the secondary users' transmission powers, and their distances and frequency separations to the primary user. Expressions for the primary user's pairwise error probability and average probability of error are derived, and an error floor prediction method is presented. Finally, the trade-off between the MAI to the primary user and the secondary users' performances are investigated through numerical examples and simulations.
{"title":"Performance Degradation Due to MAI in OFDMA-Based Cognitive Radio","authors":"Liwen Yu, L. Milstein, J. Proakis, B. Rao","doi":"10.1109/ICC.2010.5501830","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501830","url":null,"abstract":"We consider a convolutionally coded orthogonal frequency-division multiple access (OFDMA) based cognitive radio system where each user achieves perfect synchronization for its own signal, while different users are asynchronized due to random timing offsets. The presence of asynchronous secondary users introduces potential multiple access interference (MAI) to each primary user's receiver. The strength of the MAI is determined by the secondary users' transmission powers, and their distances and frequency separations to the primary user. Expressions for the primary user's pairwise error probability and average probability of error are derived, and an error floor prediction method is presented. Finally, the trade-off between the MAI to the primary user and the secondary users' performances are investigated through numerical examples and simulations.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"9 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75789891","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501973
Junchen Jiang, Yang Xu, Tian Pan, Yi Tang, B. Liu
In Network Intrusion Detection System, De-terministic Finite Automaton (DFA) is widely used to compare packet content at a constant speed against a set of patterns specified in regular expressions (regex patterns). However, combining many regex patterns into a single DFA causes a serious state explosion. Partitioning the pat-tern set into several subsets, each of which produces a small DFA, is a practical way to deflate the state explosion. In this paper, we propose a regex pattern grouping scheme based on a new DFA model called Pattern-Based DFA (P-DFA) which supports efficient pattern-based op-erations, such as insertion, deletion, and etc. By using these basic operations, one can easily measure the state explo-sion when combining a set of regex patterns into a single DFA. Based on the privilege, we develop regex grouping algorithms for mitigating the state explosion in parallel and sequential matching environments, respectively. The evaluation shows that under the same constraints, our ap-proach requires only half the number of groups compared with the most well-known algorithms.
{"title":"Pattern-Based DFA for Memory-Efficient and Scalable Multiple Regular Expression Matching","authors":"Junchen Jiang, Yang Xu, Tian Pan, Yi Tang, B. Liu","doi":"10.1109/ICC.2010.5501973","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501973","url":null,"abstract":"In Network Intrusion Detection System, De-terministic Finite Automaton (DFA) is widely used to compare packet content at a constant speed against a set of patterns specified in regular expressions (regex patterns). However, combining many regex patterns into a single DFA causes a serious state explosion. Partitioning the pat-tern set into several subsets, each of which produces a small DFA, is a practical way to deflate the state explosion. In this paper, we propose a regex pattern grouping scheme based on a new DFA model called Pattern-Based DFA (P-DFA) which supports efficient pattern-based op-erations, such as insertion, deletion, and etc. By using these basic operations, one can easily measure the state explo-sion when combining a set of regex patterns into a single DFA. Based on the privilege, we develop regex grouping algorithms for mitigating the state explosion in parallel and sequential matching environments, respectively. The evaluation shows that under the same constraints, our ap-proach requires only half the number of groups compared with the most well-known algorithms.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"66 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75812228","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501921
M. Denko, Thabo K. R. Nkwe, M. Obaidat
The cache replacement mechanism in cooperative caching has a significant bearing in determining the caches performance. Valid data items still get evicted from the cache space when new item is to be cached but there is no space available to hold it. The existence of data items in caches indicates some degree of interest on the data item. Salvaging the evicted valid data item could improve the overall caching performance. In this paper, we propose an efficient cooperative caching scheme known as CacheRescue for wireless mesh networks. The CacheRescue scheme caches data in the mesh routers expandable storage space to hold valid but evicted data items. We have used simulation to evaluate the performance of CacheRescue scheme. The simulation results show that our proposed approach improves the caching performance when compared to other existing and previously proposed caching solutions.
{"title":"Efficient Cooperative Caching with Improved Performance in Wireless Mesh Networks","authors":"M. Denko, Thabo K. R. Nkwe, M. Obaidat","doi":"10.1109/ICC.2010.5501921","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501921","url":null,"abstract":"The cache replacement mechanism in cooperative caching has a significant bearing in determining the caches performance. Valid data items still get evicted from the cache space when new item is to be cached but there is no space available to hold it. The existence of data items in caches indicates some degree of interest on the data item. Salvaging the evicted valid data item could improve the overall caching performance. In this paper, we propose an efficient cooperative caching scheme known as CacheRescue for wireless mesh networks. The CacheRescue scheme caches data in the mesh routers expandable storage space to hold valid but evicted data items. We have used simulation to evaluate the performance of CacheRescue scheme. The simulation results show that our proposed approach improves the caching performance when compared to other existing and previously proposed caching solutions.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"83 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74484633","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502635
Subodha Gunawardena, W. Zhuang
Providing multimedia services over cognitive radio (CR) networks has become an interesting research topic during past few years. As multimedia applications require specific quality of service (QoS) guarantees, supporting multimedia applications to secondary users over a CR network is a challenging task due to the random nature of resource availability. In this paper, we consider a secondary system operating over a timeslotted primary system with multiple channels and secondary users accessing the channels at the spectrum holes without interfering with primary users. We derive the voice capacity of the CR system based on the theories of effective bandwidth (EB) and effective capacity (EC). The capacity is represented in terms of the number of simultaneous independent voice calls that the system can support, providing stochastic delay guarantee. It is shown that (i) the analytical results match well with simulation results and stays slightly lower than the simulation results due to the conservative nature of the EB and EC theories, and (ii) the mean duration of channel being unavailable to secondary users has a significant impact on the system capacity. With proper medium access control, this analysis can help to develop a call admission control policy for QoS provisioning in CR networks.
{"title":"Voice Capacity of Cognitive Radio Networks","authors":"Subodha Gunawardena, W. Zhuang","doi":"10.1109/ICC.2010.5502635","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502635","url":null,"abstract":"Providing multimedia services over cognitive radio (CR) networks has become an interesting research topic during past few years. As multimedia applications require specific quality of service (QoS) guarantees, supporting multimedia applications to secondary users over a CR network is a challenging task due to the random nature of resource availability. In this paper, we consider a secondary system operating over a timeslotted primary system with multiple channels and secondary users accessing the channels at the spectrum holes without interfering with primary users. We derive the voice capacity of the CR system based on the theories of effective bandwidth (EB) and effective capacity (EC). The capacity is represented in terms of the number of simultaneous independent voice calls that the system can support, providing stochastic delay guarantee. It is shown that (i) the analytical results match well with simulation results and stays slightly lower than the simulation results due to the conservative nature of the EB and EC theories, and (ii) the mean duration of channel being unavailable to secondary users has a significant impact on the system capacity. With proper medium access control, this analysis can help to develop a call admission control policy for QoS provisioning in CR networks.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"106 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74743566","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501816
Qianxi Lu, Tao Peng, Wenbo Wang, C. Hu
The convergence of non-cooperative distributed power control in Gaussian interference channel is analyzed in this paper. Firstly, the existing distributed power control schemes are categorized as two types: gradient projection type and non-linear type, according to the iterative steps. A unified mathematical formulation is then provided for each type. The objective is extended from rate maximization, which has been studied a lot in iterative water-filling game, to more general form of utility function. Based on it, a set of sufficient conditions are derived for each type of the schemes, guaranteeing the uniqueness of the fixed point and the global convergence in a totally asynchronous manner. These convergence requirements can be interpreted as different degree of separation, according to the concrete form of utility function. To get insight into the derived convergence conditions, some numerical results are presented in the end.
{"title":"Convergence of Distributed Power Control","authors":"Qianxi Lu, Tao Peng, Wenbo Wang, C. Hu","doi":"10.1109/ICC.2010.5501816","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501816","url":null,"abstract":"The convergence of non-cooperative distributed power control in Gaussian interference channel is analyzed in this paper. Firstly, the existing distributed power control schemes are categorized as two types: gradient projection type and non-linear type, according to the iterative steps. A unified mathematical formulation is then provided for each type. The objective is extended from rate maximization, which has been studied a lot in iterative water-filling game, to more general form of utility function. Based on it, a set of sufficient conditions are derived for each type of the schemes, guaranteeing the uniqueness of the fixed point and the global convergence in a totally asynchronous manner. These convergence requirements can be interpreted as different degree of separation, according to the concrete form of utility function. To get insight into the derived convergence conditions, some numerical results are presented in the end.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"58 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73036440","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502076
Yuanliang Huang, K. Higuchi, M. Sawahashi
In this paper, in order to achieve the available spatial, temporal and frequency diversities, and also make the system implementation feasible for high speed orthogonal frequency division multiplexing (OFDM) multiple-input multiple-output (MIMO) multiplexing, a novel LSTF transmitter architecture with multiple channel encoders is proposed with each independently coded information sub-stream being threaded in the three-dimensional (3-D) space-time-frequency transmission resource array. The performance of a receiver consisting of a maximum-likelihood detector with QR decomposition and M-algorithm (QRM-MLD) is exploited, by employing irregular low-density parity-check (LDPC) code as the channel code. The threaded distribution of each coded information sub-stream in the proposed LSTF makes it to achieve the spatial, temporal and frequency diversities the same as the conventional single-encoder LSTF where coding is applied across the whole information stream, and simulation results show that the performance of the proposed multiple-encoder LSTF architecture is very close to that of the conventional single-encoder LSTF. However, due to the use of multiple parallel encoders/decoders with a shorter codeword length, the proposed LSTF architecture has much lower hardware processing speed and complexity than the conventional LSTF.
{"title":"Multiple-Encoder Layered Space-Time-Frequency Architecture with QRM-MLD Detection","authors":"Yuanliang Huang, K. Higuchi, M. Sawahashi","doi":"10.1109/ICC.2010.5502076","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502076","url":null,"abstract":"In this paper, in order to achieve the available spatial, temporal and frequency diversities, and also make the system implementation feasible for high speed orthogonal frequency division multiplexing (OFDM) multiple-input multiple-output (MIMO) multiplexing, a novel LSTF transmitter architecture with multiple channel encoders is proposed with each independently coded information sub-stream being threaded in the three-dimensional (3-D) space-time-frequency transmission resource array. The performance of a receiver consisting of a maximum-likelihood detector with QR decomposition and M-algorithm (QRM-MLD) is exploited, by employing irregular low-density parity-check (LDPC) code as the channel code. The threaded distribution of each coded information sub-stream in the proposed LSTF makes it to achieve the spatial, temporal and frequency diversities the same as the conventional single-encoder LSTF where coding is applied across the whole information stream, and simulation results show that the performance of the proposed multiple-encoder LSTF architecture is very close to that of the conventional single-encoder LSTF. However, due to the use of multiple parallel encoders/decoders with a shorter codeword length, the proposed LSTF architecture has much lower hardware processing speed and complexity than the conventional LSTF.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"3 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73067903","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502433
Hsiao-Pu Lin, Hung-Yun Hsieh
As IP telephony gains more popularity, interworking with conventional PSTN telephony has also gained more importance. In particular, an increasing number of new telephony services now involves both packet-switched (IP telephony) and circuit-switched (PSTN telephony) voice legs in one call session. One common problem that arises for enabling such new services is the need for synchronization of voice streams that traverse through heterogeneous telephony systems. In this paper, we first identify the key role of voice synchronization across heterogeneous telephony systems for services such as seamless handover between WLAN and cellular networks and multi-party audio conferencing with video overlay. We then explain the challenges in synchronizing circuit-switched and packet-switched voice streams, including codec distortion, packet losses, line noises, and overlapping utterances. To achieve voice synchronization, we proceed to investigate three different approaches based on digital speech processing techniques in the waveform, cepstrum, and spectrum domains. Finally, we compare the performance benefits and tradeoffs of different approaches, thus motivating further research along this direction.
{"title":"Voice Synchronization across Heterogeneous Telephony Systems: Problem and Solutions","authors":"Hsiao-Pu Lin, Hung-Yun Hsieh","doi":"10.1109/ICC.2010.5502433","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502433","url":null,"abstract":"As IP telephony gains more popularity, interworking with conventional PSTN telephony has also gained more importance. In particular, an increasing number of new telephony services now involves both packet-switched (IP telephony) and circuit-switched (PSTN telephony) voice legs in one call session. One common problem that arises for enabling such new services is the need for synchronization of voice streams that traverse through heterogeneous telephony systems. In this paper, we first identify the key role of voice synchronization across heterogeneous telephony systems for services such as seamless handover between WLAN and cellular networks and multi-party audio conferencing with video overlay. We then explain the challenges in synchronizing circuit-switched and packet-switched voice streams, including codec distortion, packet losses, line noises, and overlapping utterances. To achieve voice synchronization, we proceed to investigate three different approaches based on digital speech processing techniques in the waveform, cepstrum, and spectrum domains. Finally, we compare the performance benefits and tradeoffs of different approaches, thus motivating further research along this direction.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"106 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75696137","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501784
J. Misic, V. Mišić
Packet transmission in cognitive personal area networks (CPANs) may be linked to spectrum sensing, in the sense that each node is allowed to transmit a single packet in one transmission cycle, but must then `pay' for it by spectrum sensing; this ensures fairness with respect to transmission as well as the sensing burden. The amount of `payment' effort is dimensioned so as to keep the total sensing error below a pre-defined limit. We model the integrated system and evaluate its performance with respect to packet transmissions and spectrum sensing.
{"title":"Controlling Sensing Error for Cognitive PANs with 1-Limited Packet Scheduling","authors":"J. Misic, V. Mišić","doi":"10.1109/ICC.2010.5501784","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501784","url":null,"abstract":"Packet transmission in cognitive personal area networks (CPANs) may be linked to spectrum sensing, in the sense that each node is allowed to transmit a single packet in one transmission cycle, but must then `pay' for it by spectrum sensing; this ensures fairness with respect to transmission as well as the sensing burden. The amount of `payment' effort is dimensioned so as to keep the total sensing error below a pre-defined limit. We model the integrated system and evaluate its performance with respect to packet transmissions and spectrum sensing.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"19 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72712570","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502093
Ankur Bansal, P. Garg
In this paper the performance of coded cooperation has been analyzed for independent flat Nakagami-m fading channels. The outage behavior of the cooperative system has been presented and analyzed with two instantaneous variable (i.e. one with instantaneous Signal to noise ratio (SNR) and other with instantaneous received power). Finally we have presented an analytical approach to calculate the critical cooperation ratio. This gives the value of cooperation ratio ($alpha$) at which the total outage probability is minimum.
{"title":"Performance Analysis of Coded Cooperation under Nakagami-m Fading Channels","authors":"Ankur Bansal, P. Garg","doi":"10.1109/ICC.2010.5502093","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502093","url":null,"abstract":"In this paper the performance of coded cooperation has been analyzed for independent flat Nakagami-m fading channels. The outage behavior of the cooperative system has been presented and analyzed with two instantaneous variable (i.e. one with instantaneous Signal to noise ratio (SNR) and other with instantaneous received power). Finally we have presented an analytical approach to calculate the critical cooperation ratio. This gives the value of cooperation ratio ($alpha$) at which the total outage probability is minimum.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"10 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74762307","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501891
D. Schlosser, B. Staehle, A. Binzenhöfer, Björn Boder
During the last years so-called ``Thin Client'' architectures have become very popular. Thin Clients are simple end user devices, which are provided with content and services by powerful servers. Originally this concept was developed for Local Area Networks (LANs), which provide a high Quality of Service. If they are used in Wide Area Networks (WANs) they need to be adjusted accordingly in order to guarantee a good Quality of Experience (QoE). In this paper we investigate possibilities for configuring Citrix based Thin Client architectures to improve the QoE in WAN environments. We consider the benefits on the QoE as well as the costs on network layer.
{"title":"Improving the QoE of Citrix Thin Client Users","authors":"D. Schlosser, B. Staehle, A. Binzenhöfer, Björn Boder","doi":"10.1109/ICC.2010.5501891","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501891","url":null,"abstract":"During the last years so-called ``Thin Client'' architectures have become very popular. Thin Clients are simple end user devices, which are provided with content and services by powerful servers. Originally this concept was developed for Local Area Networks (LANs), which provide a high Quality of Service. If they are used in Wide Area Networks (WANs) they need to be adjusted accordingly in order to guarantee a good Quality of Experience (QoE). In this paper we investigate possibilities for configuring Citrix based Thin Client architectures to improve the QoE in WAN environments. We consider the benefits on the QoE as well as the costs on network layer.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"154 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78693957","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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