Pub Date : 2014-10-23DOI: 10.1109/ISWCS.2014.6933309
S. Schedler, V. Kühn
In wireless communications, beamforming can be exploited to reduce the power consumption considerably. If multiple relay terminals are available, distributed beamforming might be an appropriate transmission scheme. However, due to individual power constraints for all of the relays, the classical beamforming solution can no longer be used to allocate transmit power. Within this paper, closed form expressions for the optimal Power Allocation (PA) at source and regenerative relays are provided as well as an iterative algorithm to identify relay nodes that have to transmit at full power. Furthermore, numerical results will be presented for comparison to alternative relaying strategies, such as single Relay Selection (RS) and distributed Space Time Block Code (STBC). The proposed solution outperforms all the alternative approaches in terms of power consumption as well as outage probability.
{"title":"Resource allocation for distributed beamforming with multiple relays and individual power constraints","authors":"S. Schedler, V. Kühn","doi":"10.1109/ISWCS.2014.6933309","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933309","url":null,"abstract":"In wireless communications, beamforming can be exploited to reduce the power consumption considerably. If multiple relay terminals are available, distributed beamforming might be an appropriate transmission scheme. However, due to individual power constraints for all of the relays, the classical beamforming solution can no longer be used to allocate transmit power. Within this paper, closed form expressions for the optimal Power Allocation (PA) at source and regenerative relays are provided as well as an iterative algorithm to identify relay nodes that have to transmit at full power. Furthermore, numerical results will be presented for comparison to alternative relaying strategies, such as single Relay Selection (RS) and distributed Space Time Block Code (STBC). The proposed solution outperforms all the alternative approaches in terms of power consumption as well as outage probability.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129580680","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":"145 1","pages":"0"},"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}
Pub Date : 2014-10-23DOI: 10.1109/ISWCS.2014.6933412
Soufien Kammoun, Jean-Baptiste Pothin, J. Cousin
Beacon placement is one of the most prominent factors that contributes to the good performance of a localization system. A common approach for assessing the quality of a placement is based on the concept of Dilution Of Precision, which states how errors in measurements will affect the localization estimation. This paper presents an extension of DOP for RSS-based systems. It formulates the beacon-placement problem as a dilution-minimization problem with additional tradeoff between uncovered areas and over radio-coverage areas. We also propose a new algorithm based on Constrained Simulated Annealing to take into account topological constraints. Simulations show the effectiveness of our approach.
{"title":"Beacon placement using simulated annealing for RSS-based localization systems","authors":"Soufien Kammoun, Jean-Baptiste Pothin, J. Cousin","doi":"10.1109/ISWCS.2014.6933412","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933412","url":null,"abstract":"Beacon placement is one of the most prominent factors that contributes to the good performance of a localization system. A common approach for assessing the quality of a placement is based on the concept of Dilution Of Precision, which states how errors in measurements will affect the localization estimation. This paper presents an extension of DOP for RSS-based systems. It formulates the beacon-placement problem as a dilution-minimization problem with additional tradeoff between uncovered areas and over radio-coverage areas. We also propose a new algorithm based on Constrained Simulated Annealing to take into account topological constraints. Simulations show the effectiveness of our approach.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124517738","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.2014.6933321
Ramtin Rabiee, K. H. Li
For a cognitive radio network (CRN), there are many studies on transmission throughput of secondary users (SUs) with a fixed status for the primary user (PU) during the test period. In this paper, we consider a medium-traffic primary network, in which the PU changes its state (either idle or active) at most once during the frame time. This instability degrades the detection performance of SUs as well as their transmission throughput. We first try to find a suitable distribution for observed energy of the received primary signal by SUs in order to analyze the transmission throughput of the secondary network with added reliability. We then introduce the throughput expression of this particular CRN, and evaluate it under some required detection constraints, using cooperative spectrum sensing over imperfect reporting channels. The throughput analysis will be conducted for both single- and double-threshold schemes.
{"title":"Throughput analysis of secondary network over a medium-traffic primary network using cooperative spectrum sensing","authors":"Ramtin Rabiee, K. H. Li","doi":"10.1109/ISWCS.2014.6933321","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933321","url":null,"abstract":"For a cognitive radio network (CRN), there are many studies on transmission throughput of secondary users (SUs) with a fixed status for the primary user (PU) during the test period. In this paper, we consider a medium-traffic primary network, in which the PU changes its state (either idle or active) at most once during the frame time. This instability degrades the detection performance of SUs as well as their transmission throughput. We first try to find a suitable distribution for observed energy of the received primary signal by SUs in order to analyze the transmission throughput of the secondary network with added reliability. We then introduce the throughput expression of this particular CRN, and evaluate it under some required detection constraints, using cooperative spectrum sensing over imperfect reporting channels. The throughput analysis will be conducted for both single- and double-threshold schemes.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"46 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121193235","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.2014.6933467
Fatemah A. Alsewaidi, D. Kaleshi, A. Doufexi
This paper studies Machine to Machine (M2M) communications over the Long Term Evolution-Advanced (LTE-A) operating at both 2.4 GHz and 800 MHz bands. We compare the legacy frequency with the recently proposed 800 MHz band because of its enhanced propagation characteristics in indoor and outdoor environments. The performance of Radio Access Network (RAN) in the Random Access Channel (RACH) in a macro-cell environment is evaluated by considering the Signal to Noise Ratio (SNR) level for each device and the limited resources in the Physical Downlink Control Channel (PDCCH). We analyze the effect of a number of system parameters on the M2M device performance. Our study shows that operating at the 800 MHz band is a tradeoff between access success probability and average access delay. The results show higher access success probability offered by 800 MHz as compared to the legacy 2.4 GHz, while the lower band results in higher average access delay.
{"title":"Performance comparison of LTE-A RAN operating in 800MHz and 2.4GHz bands for M2M communications","authors":"Fatemah A. Alsewaidi, D. Kaleshi, A. Doufexi","doi":"10.1109/ISWCS.2014.6933467","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933467","url":null,"abstract":"This paper studies Machine to Machine (M2M) communications over the Long Term Evolution-Advanced (LTE-A) operating at both 2.4 GHz and 800 MHz bands. We compare the legacy frequency with the recently proposed 800 MHz band because of its enhanced propagation characteristics in indoor and outdoor environments. The performance of Radio Access Network (RAN) in the Random Access Channel (RACH) in a macro-cell environment is evaluated by considering the Signal to Noise Ratio (SNR) level for each device and the limited resources in the Physical Downlink Control Channel (PDCCH). We analyze the effect of a number of system parameters on the M2M device performance. Our study shows that operating at the 800 MHz band is a tradeoff between access success probability and average access delay. The results show higher access success probability offered by 800 MHz as compared to the legacy 2.4 GHz, while the lower band results in higher average access delay.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128763297","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.2014.6933326
C. Abou-Rjeily
In this paper, we analyze the repetition coding and transmit laser selection schemes over multiple-input-multiple-output free-space optical communication systems with intensity modulation and direct detection over gamma-gamma atmospheric turbulence channels. We derive novel closed-form expressions for the outage probabilities achieved by the above schemes. Through an asymptotic analysis of the outage probabilities, we prove that both schemes achieve the same diversity order that is equal to the product of the number of transmit apertures, number of receive apertures and a channel related parameter. We also prove that the superiority of the transmit laser selection scheme over the repetition coding scheme resides in a coding gain that we quantify analytically in this work.
{"title":"Diversity orders and coding gains of repetition coding and transmit laser selection over MIMO free-space optical links","authors":"C. Abou-Rjeily","doi":"10.1109/ISWCS.2014.6933326","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933326","url":null,"abstract":"In this paper, we analyze the repetition coding and transmit laser selection schemes over multiple-input-multiple-output free-space optical communication systems with intensity modulation and direct detection over gamma-gamma atmospheric turbulence channels. We derive novel closed-form expressions for the outage probabilities achieved by the above schemes. Through an asymptotic analysis of the outage probabilities, we prove that both schemes achieve the same diversity order that is equal to the product of the number of transmit apertures, number of receive apertures and a channel related parameter. We also prove that the superiority of the transmit laser selection scheme over the repetition coding scheme resides in a coding gain that we quantify analytically in this work.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128850573","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.2014.6933455
Y. Medjahdi, Mustapha Amara, J. Louveaux
Interference modelling is an important problem necessary to design and deploy wireless communication systems. Orthogonal frequency division multiplexing (OFDM) is presented as the access technique to be used for future communication systems. Therefore, it is crucial to define a quick and reliable way of estimating signal to interference plus noise ratio (SINR) for multicarrier systems. The most used approach is based on the power spectral density where the out-of-band radiation of the interfering signal is computed. In this paper, we show the inaccuracy of this technique and evaluate its deviation compared to the exact value. We also derive tight lower bound expression for the SINR evaluation. We finally validate the expression through simulation results.1.
{"title":"SINR tight lower bound for asynchronous OFDM-based multiple-access networks","authors":"Y. Medjahdi, Mustapha Amara, J. Louveaux","doi":"10.1109/ISWCS.2014.6933455","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933455","url":null,"abstract":"Interference modelling is an important problem necessary to design and deploy wireless communication systems. Orthogonal frequency division multiplexing (OFDM) is presented as the access technique to be used for future communication systems. Therefore, it is crucial to define a quick and reliable way of estimating signal to interference plus noise ratio (SINR) for multicarrier systems. The most used approach is based on the power spectral density where the out-of-band radiation of the interfering signal is computed. In this paper, we show the inaccuracy of this technique and evaluate its deviation compared to the exact value. We also derive tight lower bound expression for the SINR evaluation. We finally validate the expression through simulation results.1.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115204407","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.2014.6933436
Màrius Caus, A. Pérez-Neira, M. Moretti, Adrian Kliks
This paper addresses the margin adaptive problem for the filter bank multicarrier (FBMC) modulation based on the offset QAM (OQAM), referred to as FBMC/OQAM. The analysis conducted in this paper reveals that due to the specific FBMC/OQAM transmission format the system has to deal with inter-user, inter-symbol and inter-carrier interference to solve the resource allocation problem. To manage the interference, the successive channel allocation method, originally proposed for the orthogonal frequency division multiplexing (OFDM), has been modified by organizing subcarriers in groups and assigning subcarriers to users in a block-wise fashion. Following this strategy and making some approximations we demonstrate that it is possible to pose a single problem that is valid for OFDM and FBMC/OQAM. In this case, numerical results show that FBMC/OQAM is more energy-efficient than OFDM because it requires less power to transmit the same information rate.
{"title":"A margin adaptive scheduling algorithm for FBMC/OQAM systems","authors":"Màrius Caus, A. Pérez-Neira, M. Moretti, Adrian Kliks","doi":"10.1109/ISWCS.2014.6933436","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933436","url":null,"abstract":"This paper addresses the margin adaptive problem for the filter bank multicarrier (FBMC) modulation based on the offset QAM (OQAM), referred to as FBMC/OQAM. The analysis conducted in this paper reveals that due to the specific FBMC/OQAM transmission format the system has to deal with inter-user, inter-symbol and inter-carrier interference to solve the resource allocation problem. To manage the interference, the successive channel allocation method, originally proposed for the orthogonal frequency division multiplexing (OFDM), has been modified by organizing subcarriers in groups and assigning subcarriers to users in a block-wise fashion. Following this strategy and making some approximations we demonstrate that it is possible to pose a single problem that is valid for OFDM and FBMC/OQAM. In this case, numerical results show that FBMC/OQAM is more energy-efficient than OFDM because it requires less power to transmit the same information rate.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127266291","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.2014.6933335
Rikke Apelfrojd, M. Sternad
Coordinated Multipoint (CoMP) transmission provides high theoretic gains in spectral efficiency, in particular with coherent linear Joint Transmission (JT) to multiple users. However, this requires high backhaul capacity. If the backhaul requirement cannot be met by the system, then CoMP gains decrease as the linear precoder matrix must be adjusted to include zeros. To minimize the loss of CoMP gains, all elements in the precoder should be adjusted as zeros are added to the precoder. We here propose a low complexity method for adjusting a precoder matrix when some elements are required to be zero, with respect to a robust MSE criterion. This is done by introducing penalties on specific precoder matrix elements. This generalized MSE criterion can then be used as a low complexity tool for optimizing e.g. with respect to sum-rate. Results show that this does indeed provide a better solution than if zeros are added separately. It is especially beneficial for cell edge users, i.e. for the same users that can gain the most from JT CoMP.
{"title":"Robust linear precoder for coordinated multipoint joint transmission under limited backhaul with imperfect CSI","authors":"Rikke Apelfrojd, M. Sternad","doi":"10.1109/ISWCS.2014.6933335","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933335","url":null,"abstract":"Coordinated Multipoint (CoMP) transmission provides high theoretic gains in spectral efficiency, in particular with coherent linear Joint Transmission (JT) to multiple users. However, this requires high backhaul capacity. If the backhaul requirement cannot be met by the system, then CoMP gains decrease as the linear precoder matrix must be adjusted to include zeros. To minimize the loss of CoMP gains, all elements in the precoder should be adjusted as zeros are added to the precoder. We here propose a low complexity method for adjusting a precoder matrix when some elements are required to be zero, with respect to a robust MSE criterion. This is done by introducing penalties on specific precoder matrix elements. This generalized MSE criterion can then be used as a low complexity tool for optimizing e.g. with respect to sum-rate. Results show that this does indeed provide a better solution than if zeros are added separately. It is especially beneficial for cell edge users, i.e. for the same users that can gain the most from JT CoMP.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131082521","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.2014.6933454
V. Stanivuk, Stefan Tomic, M. Narandzic, S. Nedic
This paper proposes 2×2 MIMO OQAM/FBMC receiver strategy based on successive interference cancellation (SIC) as an extension of the SISO approach which uses entirely real-valued formulation of the transmission system model]. Both increase of throughput and SNR gain are observed through appropriate maximum ratio combining (MRC) of the soft symbols pertaining to the receiver-end diversity branches. The 2×1 multi-user detection (MUD) case has been also addressed to certain extent. Additional gains, essentially related to SISO case, coming from the cooperative use of in-phase (I) and quadrature (Q) branches, primarily based on the quadrature noise components' independence, as well as from the explicit noise cancellation within the SIC framework, have also been outlined.
{"title":"Real-domain SIC for MIMO with FBMC waveforms","authors":"V. Stanivuk, Stefan Tomic, M. Narandzic, S. Nedic","doi":"10.1109/ISWCS.2014.6933454","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933454","url":null,"abstract":"This paper proposes 2×2 MIMO OQAM/FBMC receiver strategy based on successive interference cancellation (SIC) as an extension of the SISO approach which uses entirely real-valued formulation of the transmission system model]. Both increase of throughput and SNR gain are observed through appropriate maximum ratio combining (MRC) of the soft symbols pertaining to the receiver-end diversity branches. The 2×1 multi-user detection (MUD) case has been also addressed to certain extent. Additional gains, essentially related to SISO case, coming from the cooperative use of in-phase (I) and quadrature (Q) branches, primarily based on the quadrature noise components' independence, as well as from the explicit noise cancellation within the SIC framework, have also been outlined.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133918457","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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