Pub Date : 2014-10-23DOI: 10.1109/ISWCS.2014.6933399
M. Mackowiak, L. Correia, Adrian Kliks, P. Kryszkiewicz
In this paper the Multiple-Input-Single-Output (MISO) antenna system is considered, where a set of wearable antennas is deployed on various locations on the body, in order to enhance the connection reliability with the distant cellular-network receiver. Two body dynamics in a street scenario, i.e., run straight and run in loop are analysed. First of all, using the Geometrically Based Stochastical Channel Model adapted to Body Area Networks, the channel parameters were analysed. On average, the difference between the maximum and minimum values of path loss from different wearable antennas and external receiver is equal to 23 dB. Moreover, the capacity of the system is studied, and the application of bit-and-power loading schemes in MISO-OFDM systems is presented. Depending on the body position in the street, the average data rate varies in [2, 5.5] bps/Hz.
{"title":"MIMO channel analysis in the context of body area networks","authors":"M. Mackowiak, L. Correia, Adrian Kliks, P. Kryszkiewicz","doi":"10.1109/ISWCS.2014.6933399","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933399","url":null,"abstract":"In this paper the Multiple-Input-Single-Output (MISO) antenna system is considered, where a set of wearable antennas is deployed on various locations on the body, in order to enhance the connection reliability with the distant cellular-network receiver. Two body dynamics in a street scenario, i.e., run straight and run in loop are analysed. First of all, using the Geometrically Based Stochastical Channel Model adapted to Body Area Networks, the channel parameters were analysed. On average, the difference between the maximum and minimum values of path loss from different wearable antennas and external receiver is equal to 23 dB. Moreover, the capacity of the system is studied, and the application of bit-and-power loading schemes in MISO-OFDM systems is presented. Depending on the body position in the street, the average data rate varies in [2, 5.5] bps/Hz.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127065475","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933384
Giancarlo Pastor, Inmaculada Mora-Jiménez, A. Caamaño, Riku Jantti
The Edgeworth expansion approximates nearly Gaussian distributions in terms of cumulants. This expansion is developed within the framework of First Kind Statistics, where definitions are derived from the Fourier transform. Alternatively, the framework of Second Kind Statistics offers analogous definitions which are derived from the Mellin transform. Although a formalism with such similarity to the existing definitions cannot lead to intrinsically new results, statistical methods within this new framework has been understudied. This paper introduces an Edgeworth expansion in terms of log-cumulants, which are the analogous to cumulants for the Second Kind statistics. More importantly, this new expansion approximates asymmetric distributions which are commonly-found in aggregate interference modeling.
{"title":"Log-cumulants-based Edgeworth expansion for skew-distributed aggregate interference","authors":"Giancarlo Pastor, Inmaculada Mora-Jiménez, A. Caamaño, Riku Jantti","doi":"10.1109/ISWCS.2014.6933384","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933384","url":null,"abstract":"The Edgeworth expansion approximates nearly Gaussian distributions in terms of cumulants. This expansion is developed within the framework of First Kind Statistics, where definitions are derived from the Fourier transform. Alternatively, the framework of Second Kind Statistics offers analogous definitions which are derived from the Mellin transform. Although a formalism with such similarity to the existing definitions cannot lead to intrinsically new results, statistical methods within this new framework has been understudied. This paper introduces an Edgeworth expansion in terms of log-cumulants, which are the analogous to cumulants for the Second Kind statistics. More importantly, this new expansion approximates asymmetric distributions which are commonly-found in aggregate interference modeling.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130089829","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933421
R. Fritzsche, G. Fettweis
In mobile slow fading scenarios, channel state information (CSI) is required at the transmitter to adapt the data transmission strategy to the current channel state. In this regard, precoding in multiuser-multiple-input-multiple-output (MU-MIMO) downlink systems is a prominent example. In frequency division duplex, channel observations are quantized and fed back via the uplink, protected by an error correction code. The quantization resolution together with the code strength correspond to a certain amount of feedback bits. For a limited number of uplink signaling resources, there is a trade-off between investing bits for increasing the quantization resolution or for improving the error correction capability. While existing feedback schemes use a fixed quantization resolution, this work proposes a scheme which finds the optimal number of quantization bits for minimizing the channel uncertainty at the transmitter. Simulation results verify the proposed solution and apply it to precoded transmission in a MU-MIMO downlink system.
{"title":"Optimized quantization resolution for limited CSI feedback with outage","authors":"R. Fritzsche, G. Fettweis","doi":"10.1109/ISWCS.2014.6933421","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933421","url":null,"abstract":"In mobile slow fading scenarios, channel state information (CSI) is required at the transmitter to adapt the data transmission strategy to the current channel state. In this regard, precoding in multiuser-multiple-input-multiple-output (MU-MIMO) downlink systems is a prominent example. In frequency division duplex, channel observations are quantized and fed back via the uplink, protected by an error correction code. The quantization resolution together with the code strength correspond to a certain amount of feedback bits. For a limited number of uplink signaling resources, there is a trade-off between investing bits for increasing the quantization resolution or for improving the error correction capability. While existing feedback schemes use a fixed quantization resolution, this work proposes a scheme which finds the optimal number of quantization bits for minimizing the channel uncertainty at the transmitter. Simulation results verify the proposed solution and apply it to precoded transmission in a MU-MIMO downlink system.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129033887","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933461
Ivan Ganchev, Zhanlin Ji, M. O'Droma
This paper describes the design and implementation of a cloud-based service recommendation system used to discover and suggest to users the `best' mobile services in the emerging ubiquitous consumer wireless world (UCWW). With this distributed system, the UCWW cloud provider collects user behavior (e.g., Internet logs, web browsing, searching for services, participation in social networks, online shopping, friends' recommendations for services, etc.), analyzes this `big data' in the cloud, and recommends the `best' mobile services applicable to that particular user under the always best connected and best served (ABC&S) paradigm. A number of novel software solutions, both on the user- and cloud side, are proposed. An approach towards running this service recommendation system in a flexible and intelligent way is elaborated.
{"title":"A cloud-based service recommendation system for use in UCWW","authors":"Ivan Ganchev, Zhanlin Ji, M. O'Droma","doi":"10.1109/ISWCS.2014.6933461","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933461","url":null,"abstract":"This paper describes the design and implementation of a cloud-based service recommendation system used to discover and suggest to users the `best' mobile services in the emerging ubiquitous consumer wireless world (UCWW). With this distributed system, the UCWW cloud provider collects user behavior (e.g., Internet logs, web browsing, searching for services, participation in social networks, online shopping, friends' recommendations for services, etc.), analyzes this `big data' in the cloud, and recommends the `best' mobile services applicable to that particular user under the always best connected and best served (ABC&S) paradigm. A number of novel software solutions, both on the user- and cloud side, are proposed. An approach towards running this service recommendation system in a flexible and intelligent way is elaborated.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130907459","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933415
Oussama Lazrak, C. Moy
This paper focuses on the design and implementation processes of Cognitive radio equipments. The implementation is based on Oriented Object approach, C++ language and USRP platforms for the radio interface. The design is based on HDCRAM Architecture for better modularity and reusability. We develop a framework which provides the necessary mechanisms for developers to carry out different cognitive scenarios. We presented a scenario already implemented and tested. The use of this approach significantly reduces errors and time of development.
{"title":"Model-based development for cognitive radio applications","authors":"Oussama Lazrak, C. Moy","doi":"10.1109/ISWCS.2014.6933415","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933415","url":null,"abstract":"This paper focuses on the design and implementation processes of Cognitive radio equipments. The implementation is based on Oriented Object approach, C++ language and USRP platforms for the radio interface. The design is based on HDCRAM Architecture for better modularity and reusability. We develop a framework which provides the necessary mechanisms for developers to carry out different cognitive scenarios. We presented a scenario already implemented and tested. The use of this approach significantly reduces errors and time of development.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131014109","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933318
G. Capdehourat, Federico Larroca, P. Belzarena
In recent years we have seen the success of wireless communications in unlicensed frequency bands, mainly driven by the 802.11 standard. The clear trend in the growth of traffic demand suggests that spectrum scarcity will be a serious threat to reach the capacity needs in the near future. Looking for more available spectrum, regulators have already begun to study secondary assignments in licensed bands, based on the recent cognitive network paradigm. In this context, we focus our work in the analysis of optimum spectrum allocation mechanisms. We introduce a stochastic model to formulate the problem, considering primary users' activity and a periodically scheduled assignment scheme. To solve the problem we propose a novel robust solution, which we argue is superior to an expectation based approach, comparing both alternatives through extensive simulations.
{"title":"Robust spectrum allocation for cognitive radio networks","authors":"G. Capdehourat, Federico Larroca, P. Belzarena","doi":"10.1109/ISWCS.2014.6933318","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933318","url":null,"abstract":"In recent years we have seen the success of wireless communications in unlicensed frequency bands, mainly driven by the 802.11 standard. The clear trend in the growth of traffic demand suggests that spectrum scarcity will be a serious threat to reach the capacity needs in the near future. Looking for more available spectrum, regulators have already begun to study secondary assignments in licensed bands, based on the recent cognitive network paradigm. In this context, we focus our work in the analysis of optimum spectrum allocation mechanisms. We introduce a stochastic model to formulate the problem, considering primary users' activity and a periodically scheduled assignment scheme. To solve the problem we propose a novel robust solution, which we argue is superior to an expectation based approach, comparing both alternatives through extensive simulations.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123220913","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933482
F. Awad, E. Taqieddin, M. Mowafi, O. Banimelhem, Amani AbuQdais
As the demand for large-scale wireless multimedia sensor networks increases, so does the need for well-designed protocols that optimize the utilization of available networks resources. This requires experimental testing for realistic performance evaluation and design tuning. However, experimental testing of large-scale wireless networks using hardware testbeds is usually very hard to perform due to the need for collecting and monitoring the performance metrics data for multiple sensor nodes all at the same time, especially the node's energy consumption data. On the other hand, pure simulation testing may not accurately replicate the real-life scenarios, especially those parameters that are related to the wireless signal behavior in special environments. Therefore, this work attempts to close this gap between experimental and simulation testing. This paper presents a scalable simulation testbed that attempts to mimic our previously designed small-scale hardware testbed for wireless multimedia sensor networks by tuning the simulation parameters to match the real-life measurements obtained via experimental testing. The proposed simulation testbed embeds the JPEG and JPEG2000 image compression algorithms and potentially allows for network-controlled image compression and transmission decisions. The simulation results show very close match to the small-scale experimental testing as well as to the hypothetical large-scale extensions that were based on the experimental results.
{"title":"A simulation testbed to jointly exploit multiple image compression techniques for wireless multimedia sensor networks","authors":"F. Awad, E. Taqieddin, M. Mowafi, O. Banimelhem, Amani AbuQdais","doi":"10.1109/ISWCS.2014.6933482","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933482","url":null,"abstract":"As the demand for large-scale wireless multimedia sensor networks increases, so does the need for well-designed protocols that optimize the utilization of available networks resources. This requires experimental testing for realistic performance evaluation and design tuning. However, experimental testing of large-scale wireless networks using hardware testbeds is usually very hard to perform due to the need for collecting and monitoring the performance metrics data for multiple sensor nodes all at the same time, especially the node's energy consumption data. On the other hand, pure simulation testing may not accurately replicate the real-life scenarios, especially those parameters that are related to the wireless signal behavior in special environments. Therefore, this work attempts to close this gap between experimental and simulation testing. This paper presents a scalable simulation testbed that attempts to mimic our previously designed small-scale hardware testbed for wireless multimedia sensor networks by tuning the simulation parameters to match the real-life measurements obtained via experimental testing. The proposed simulation testbed embeds the JPEG and JPEG2000 image compression algorithms and potentially allows for network-controlled image compression and transmission decisions. The simulation results show very close match to the small-scale experimental testing as well as to the hypothetical large-scale extensions that were based on the experimental results.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126007131","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933423
D. Alves, Renato B. Machado, D. B. D. Costa, A. P. Legg, B. Filho
We propose a dynamic hybrid antenna/relay selection scheme for multiple-access relay systems. The proposed scheme aims to boost the system throughput while keeping a good error performance. By using the channel state information, the destination node performs a dynamic selection between the signals provided by the multi-antenna relay, located in the inter-cell region, and the relay nodes geographically distributed over the cells. The multi-antenna relay and the single-antenna relay nodes employ the decode-remodulate-and-forward and amplify-and-forward protocols, respectively. Results reveal that the proposed scheme offers a good tradeoff between spectral efficiency and diversity gain, which is one of the main requirements for the next generation of wireless communications systems.
{"title":"A dynamic hybrid antenna/relay selection scheme for the multiple-access relay channel","authors":"D. Alves, Renato B. Machado, D. B. D. Costa, A. P. Legg, B. Filho","doi":"10.1109/ISWCS.2014.6933423","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933423","url":null,"abstract":"We propose a dynamic hybrid antenna/relay selection scheme for multiple-access relay systems. The proposed scheme aims to boost the system throughput while keeping a good error performance. By using the channel state information, the destination node performs a dynamic selection between the signals provided by the multi-antenna relay, located in the inter-cell region, and the relay nodes geographically distributed over the cells. The multi-antenna relay and the single-antenna relay nodes employ the decode-remodulate-and-forward and amplify-and-forward protocols, respectively. Results reveal that the proposed scheme offers a good tradeoff between spectral efficiency and diversity gain, which is one of the main requirements for the next generation of wireless communications systems.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123801015","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933371
D. Plets, W. Joseph, K. Vanhecke, G. Vermeeren, S. Aerts, M. Deruyck, L. Martens
In this paper, for the first time a tool is presented that allows the prediction of whole-body and localized Specific Absorption Rates (SARs) and absorbed doses for indoor network deployments. As an application, three scenarios are investigated, considering different network topologies for data traffic over WiFi and for phone call traffic over Universal Mobile Telecommunications System (UMTS). Also, the influence of phone call duration on the total absorbed dose is spatially and globally characterized. SARs and absorbed doses can be lowered when more base stations with a lower transmit power are installed. For the considered scenarios, a reduction by a factor 24 is observed for the downlink SAR in a WiFi deployment, and by a factor 2.4 for the uplink SAR in a UMTS deployment.
{"title":"Whole-body and localized SAR and dose prediction tool for indoor wireless network deployments","authors":"D. Plets, W. Joseph, K. Vanhecke, G. Vermeeren, S. Aerts, M. Deruyck, L. Martens","doi":"10.1109/ISWCS.2014.6933371","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933371","url":null,"abstract":"In this paper, for the first time a tool is presented that allows the prediction of whole-body and localized Specific Absorption Rates (SARs) and absorbed doses for indoor network deployments. As an application, three scenarios are investigated, considering different network topologies for data traffic over WiFi and for phone call traffic over Universal Mobile Telecommunications System (UMTS). Also, the influence of phone call duration on the total absorbed dose is spatially and globally characterized. SARs and absorbed doses can be lowered when more base stations with a lower transmit power are installed. For the considered scenarios, a reduction by a factor 24 is observed for the downlink SAR in a WiFi deployment, and by a factor 2.4 for the uplink SAR in a UMTS deployment.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115417383","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933452
Saloua Hendaoui, N. Zangar, S. Tabbane
LTE (Long Term Evolution) is a broadband wireless communication specified by the 3GPP (Third Generation Partnership Project) on the way towards fourth-generation mobile. User traffic can be classified into two main classes which are RT (Real Time) and NRT traffic. To respond to RT's QoS requirements, resource allocation steps must be as optimal as possible. In this paper, we propose a new concept of estimation of reception time to avoid scheduling packets that may eventually be dropped inside their destination. The main objective of this proposition is to reduce radio blocks' wasting. The behavior of the scheduler has been simulated to check its performance. Simulations prove that the proposed scheme overcome existed schedulers.
{"title":"QoS aware pre-emption: A new proposition for LTE downlink schedulers","authors":"Saloua Hendaoui, N. Zangar, S. Tabbane","doi":"10.1109/ISWCS.2014.6933452","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933452","url":null,"abstract":"LTE (Long Term Evolution) is a broadband wireless communication specified by the 3GPP (Third Generation Partnership Project) on the way towards fourth-generation mobile. User traffic can be classified into two main classes which are RT (Real Time) and NRT traffic. To respond to RT's QoS requirements, resource allocation steps must be as optimal as possible. In this paper, we propose a new concept of estimation of reception time to avoid scheduling packets that may eventually be dropped inside their destination. The main objective of this proposition is to reduce radio blocks' wasting. The behavior of the scheduler has been simulated to check its performance. Simulations prove that the proposed scheme overcome existed schedulers.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114201759","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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