Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632083
Y. Balboul, F. Mrabti, Najiba El Amrani El Idrissi
The frequency reuse technique adopted in the LTE (long term evolution) target a high bitrate and QoS but is hampered by the significant increase of the number of users. In this work, to improve the downlink radio link, we will use, in the inner-cell, the frequency reuse and LP-OFDM modulation. In the cell-edge we will use the frequency reuse and OFDM modulation supported by the coordination with adjacent cells. Matlab simulation of different scenarios showed an improvement in bit error rate at the receiver. As a result For inner-cell the use of LP-OFDM with iterative receiver, results in an increase of gain of about 2 dB for SNR (Signal to Noise Ratio) higher than 3 dB. For the cell-edge, combining multiple physical resources, improves significantly the transmission conditions with a gain of 3 dB with 2 PRB (physical resource block) and a gain greater than 6 dB with 3 PRB allocations. The results are processed according to the Monte Carlo criteria.
{"title":"LTE — Improving quality reception in downlink radio resources links","authors":"Y. Balboul, F. Mrabti, Najiba El Amrani El Idrissi","doi":"10.1109/ICTEL.2013.6632083","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632083","url":null,"abstract":"The frequency reuse technique adopted in the LTE (long term evolution) target a high bitrate and QoS but is hampered by the significant increase of the number of users. In this work, to improve the downlink radio link, we will use, in the inner-cell, the frequency reuse and LP-OFDM modulation. In the cell-edge we will use the frequency reuse and OFDM modulation supported by the coordination with adjacent cells. Matlab simulation of different scenarios showed an improvement in bit error rate at the receiver. As a result For inner-cell the use of LP-OFDM with iterative receiver, results in an increase of gain of about 2 dB for SNR (Signal to Noise Ratio) higher than 3 dB. For the cell-edge, combining multiple physical resources, improves significantly the transmission conditions with a gain of 3 dB with 2 PRB (physical resource block) and a gain greater than 6 dB with 3 PRB allocations. The results are processed according to the Monte Carlo criteria.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"195 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123009224","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632066
Ke Wang, Chi Zhang, Lei Cao, Yongyu Chang, Dacheng Yang
Heterogeneous network (HetNet) has been studied earlier in the context of LTE. But lately, there are also some discussions about HetNet in HSPA. Cross-tier interference (CTI) is an annoying issue to be investigated in the co-channel HSPA HetNet (CHH) scenario. In this paper, we will focus on the downlink CTI problem in CHH and propose a solution to mitigate it. Our scheme involves the macro muting (MM) in which macro NodeB will mute itself at some certain sub-frames to reduce the CTI level in the system. We also enhance the MM scheme by introducing the adaptive CQI hysteresis (ACH) mechanism to avoid the issue that the low power node (LPN) in HetNet may use the improper CQI for transmitting when MM is implemented. Simulation results will show the benefits of our proposed scheme.
{"title":"Cross-tier interference coordination of macro muting based on adaptive CQI hysteresis in HSPA heterogeneous network","authors":"Ke Wang, Chi Zhang, Lei Cao, Yongyu Chang, Dacheng Yang","doi":"10.1109/ICTEL.2013.6632066","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632066","url":null,"abstract":"Heterogeneous network (HetNet) has been studied earlier in the context of LTE. But lately, there are also some discussions about HetNet in HSPA. Cross-tier interference (CTI) is an annoying issue to be investigated in the co-channel HSPA HetNet (CHH) scenario. In this paper, we will focus on the downlink CTI problem in CHH and propose a solution to mitigate it. Our scheme involves the macro muting (MM) in which macro NodeB will mute itself at some certain sub-frames to reduce the CTI level in the system. We also enhance the MM scheme by introducing the adaptive CQI hysteresis (ACH) mechanism to avoid the issue that the low power node (LPN) in HetNet may use the improper CQI for transmitting when MM is implemented. Simulation results will show the benefits of our proposed scheme.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134312974","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632072
M. Manna, Walid M. Qaja, J. Chambers
In this paper we present a modified quasiorthogonal space-time block coding (M QO-STBC) scheme with full diversity and code gain distance (CGD) for use in asynchronous relay networks. We implement an orthogonal frequency division multiplexing (OFDM) scheme with cyclic prefix (CP) at the source to mitigate the effects of random delays between the relay nodes and the destination caused by asynchronism. The modified code is structured by using a proper signal rotation and set partitioning of two quasi-orthogonal codebooks. Furthermore, the best two relays are selected from a set of M available relays based on the end-to-end instantaneous path gains. Simulation results show that the OFDM-based scheme can significantly enhance the performance of the system under imperfect synchronization. Simulations also shows that the relay selection improved the reliability of the link as compared to a conventional system.
{"title":"OFDM-based modified quasi-orthogonal space-time scheme for use in asynchronous cooperative networks with relay selection","authors":"M. Manna, Walid M. Qaja, J. Chambers","doi":"10.1109/ICTEL.2013.6632072","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632072","url":null,"abstract":"In this paper we present a modified quasiorthogonal space-time block coding (M QO-STBC) scheme with full diversity and code gain distance (CGD) for use in asynchronous relay networks. We implement an orthogonal frequency division multiplexing (OFDM) scheme with cyclic prefix (CP) at the source to mitigate the effects of random delays between the relay nodes and the destination caused by asynchronism. The modified code is structured by using a proper signal rotation and set partitioning of two quasi-orthogonal codebooks. Furthermore, the best two relays are selected from a set of M available relays based on the end-to-end instantaneous path gains. Simulation results show that the OFDM-based scheme can significantly enhance the performance of the system under imperfect synchronization. Simulations also shows that the relay selection improved the reliability of the link as compared to a conventional system.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134334686","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632121
Tarik Moataz, Abdullatif Shikfa, N. Cuppens-Boulahia, F. Cuppens
Searchable encryption is a promising primitive in the context of outsourced data storage and in particular cloud computing. Current constructions lack searching capabilities beyond exact search on keywords and are thus less efficient than plaintext algorithm that take into account the meaning and return results corresponding to semantically close keywords. We thus advocate for the need of semantic search over encrypted data. We study the state of the art in stemming algorithms and in searchable encryption and propose the first semantic symmetric searchable encryption constructions. This improvement over searchable encryption has similar security as the prior work of Curtmola et al. on symmetric searchable encryption.
{"title":"Semantic search over encrypted data","authors":"Tarik Moataz, Abdullatif Shikfa, N. Cuppens-Boulahia, F. Cuppens","doi":"10.1109/ICTEL.2013.6632121","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632121","url":null,"abstract":"Searchable encryption is a promising primitive in the context of outsourced data storage and in particular cloud computing. Current constructions lack searching capabilities beyond exact search on keywords and are thus less efficient than plaintext algorithm that take into account the meaning and return results corresponding to semantically close keywords. We thus advocate for the need of semantic search over encrypted data. We study the state of the art in stemming algorithms and in searchable encryption and propose the first semantic symmetric searchable encryption constructions. This improvement over searchable encryption has similar security as the prior work of Curtmola et al. on symmetric searchable encryption.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"363 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115976894","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632141
R. Mesleh, H. Elgala, T. Little
Thermal management is a significant issue in the design of high power light emitting diodes (LEDs). In this letter, the effect of practical changes in the LED junction temperature on the performance of indoor optical wireless (OW) communication system based orthogonal frequency division multiplexing (OFDM) modulation is studied and analyzed. Junction temperature changes occur due to variations in the drive current, ambient temperature and by self-heating due to electrical power dissipation. The changes in junction temperature affect the LED forward voltage, the output luminous flux and the LED dominant wavelength. The effects of these changes on the performance of DC-biased (DCO) and asymmetrically clipped (ACO) OW OFDM systems are studied. While it is shown that the changes in the dominant wavelength are insignificant, it will be shown that significant performance degradation may occur due to small variations of LED forward voltage and luminous flux.
{"title":"On the performance degradation of optical wireless OFDM communication systems due to changes in the LED junction temperature","authors":"R. Mesleh, H. Elgala, T. Little","doi":"10.1109/ICTEL.2013.6632141","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632141","url":null,"abstract":"Thermal management is a significant issue in the design of high power light emitting diodes (LEDs). In this letter, the effect of practical changes in the LED junction temperature on the performance of indoor optical wireless (OW) communication system based orthogonal frequency division multiplexing (OFDM) modulation is studied and analyzed. Junction temperature changes occur due to variations in the drive current, ambient temperature and by self-heating due to electrical power dissipation. The changes in junction temperature affect the LED forward voltage, the output luminous flux and the LED dominant wavelength. The effects of these changes on the performance of DC-biased (DCO) and asymmetrically clipped (ACO) OW OFDM systems are studied. While it is shown that the changes in the dominant wavelength are insignificant, it will be shown that significant performance degradation may occur due to small variations of LED forward voltage and luminous flux.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114672154","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632147
R. Kwan
Radio Resource Management (RRM) and Self-Organizing Network (SON) are two very important aspects of today's wireless cellular networks. Among them lies the fundamental notion of cell load. An accurate estimation of the cell load facilitates optimal operations of RRM/SON algorithms. In the case when frequency-domain power control (FDPC) is employed in mitigating intercell interference, transmit power spectral density can be non-uniform by design. Thus, it is no longer relevant to define the cell load simply in terms of frequency resource utilization as in existing literatures. In this paper, load estimation methods are proposed in the context of FDPC for LTE downlink, and an numerical illustration is provided.
{"title":"On downlink load estimation for LTE in the context of self-organizing networks","authors":"R. Kwan","doi":"10.1109/ICTEL.2013.6632147","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632147","url":null,"abstract":"Radio Resource Management (RRM) and Self-Organizing Network (SON) are two very important aspects of today's wireless cellular networks. Among them lies the fundamental notion of cell load. An accurate estimation of the cell load facilitates optimal operations of RRM/SON algorithms. In the case when frequency-domain power control (FDPC) is employed in mitigating intercell interference, transmit power spectral density can be non-uniform by design. Thus, it is no longer relevant to define the cell load simply in terms of frequency resource utilization as in existing literatures. In this paper, load estimation methods are proposed in the context of FDPC for LTE downlink, and an numerical illustration is provided.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"180 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116457126","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632077
M. Lasanen, Marc Aubree, C. Cassan, A. Conte, J. David, S. Elayoubi, Timo Galkin, V. Grigore, S. Masson, J. Lees, H. Louahlia-Gualous, D. Marquet, Z. Mokhti, L. Nuaymi, H. Scheck, L. Smalen
Reducing the overall environmental impact of mobile radio networks is a central factor in achieving improved mobile services whilst at the same time enabling a growing telecommunications industry in emerging markets. The OPERA-Net-2 (Optimising Power Efficiency in Mobile Radio Networks 2) project concentrates on this challenge, addressing both energy and material efficiencies of 3G, 4G and heterogeneous networks, while also considering the use of renewable energy sources. This paper presents an insight into the project after its first year and discusses research trends in `green communications networks' for the future.
{"title":"Environmental friendly mobile radio networks: Approaches of the European OPERA-Net 2 project","authors":"M. Lasanen, Marc Aubree, C. Cassan, A. Conte, J. David, S. Elayoubi, Timo Galkin, V. Grigore, S. Masson, J. Lees, H. Louahlia-Gualous, D. Marquet, Z. Mokhti, L. Nuaymi, H. Scheck, L. Smalen","doi":"10.1109/ICTEL.2013.6632077","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632077","url":null,"abstract":"Reducing the overall environmental impact of mobile radio networks is a central factor in achieving improved mobile services whilst at the same time enabling a growing telecommunications industry in emerging markets. The OPERA-Net-2 (Optimising Power Efficiency in Mobile Radio Networks 2) project concentrates on this challenge, addressing both energy and material efficiencies of 3G, 4G and heterogeneous networks, while also considering the use of renewable energy sources. This paper presents an insight into the project after its first year and discusses research trends in `green communications networks' for the future.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117026879","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632085
L. Kanaris, Akis Kokkinis, A. Liotta, M. Raspopoulos, S. Stavrou
This work proposes a novel methodology for the evaluation of indoor positioning systems, by adopting a binomial distribution approach during the evaluation process. The positioning accuracy achieved by any Real Time Localisation System (RTLS) is affected by various critical factors, such as the network infrastructure, the implemented positioning algorithms, the environment complexity, the dynamic changes that occur, the device diversity etc. The aim of the suggested methodology is to allow the evaluation of the expected accuracy of a deployed positioning system, under its actual operating conditions. The data collected by the binomial experiment is statistically processed, in order for the evaluator to calculate the strength of his evidence, and finally decide whether the declared accuracy can actually be met or not. The proposed approach, due to its robustness, can be of significant value in device diversity scenarios, organic and dynamic environments.
{"title":"A binomial distribution approach for the evaluation of indoor positioning systems","authors":"L. Kanaris, Akis Kokkinis, A. Liotta, M. Raspopoulos, S. Stavrou","doi":"10.1109/ICTEL.2013.6632085","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632085","url":null,"abstract":"This work proposes a novel methodology for the evaluation of indoor positioning systems, by adopting a binomial distribution approach during the evaluation process. The positioning accuracy achieved by any Real Time Localisation System (RTLS) is affected by various critical factors, such as the network infrastructure, the implemented positioning algorithms, the environment complexity, the dynamic changes that occur, the device diversity etc. The aim of the suggested methodology is to allow the evaluation of the expected accuracy of a deployed positioning system, under its actual operating conditions. The data collected by the binomial experiment is statistically processed, in order for the evaluator to calculate the strength of his evidence, and finally decide whether the declared accuracy can actually be met or not. The proposed approach, due to its robustness, can be of significant value in device diversity scenarios, organic and dynamic environments.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121445658","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632149
Chafika Tata, M. Kadoch
This paper proposes a new Bandwidth Constraints Model for MPLS networks, called CAM (Courteous Allocation Model). CAM allocates added bandwidth to lower classes of traffic without affecting the high priority traffic. Simulations are performed to compare CAM with the two basic Constraints Models, namely, MAM (Maximum Allocation Model) and RDM (Russian Dolls Model). The results show that our model gives significant improvement in terms of delay, throughput and packets loss.
{"title":"CAM: Courteous bandwidth constraints allocation model","authors":"Chafika Tata, M. Kadoch","doi":"10.1109/ICTEL.2013.6632149","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632149","url":null,"abstract":"This paper proposes a new Bandwidth Constraints Model for MPLS networks, called CAM (Courteous Allocation Model). CAM allocates added bandwidth to lower classes of traffic without affecting the high priority traffic. Simulations are performed to compare CAM with the two basic Constraints Models, namely, MAM (Maximum Allocation Model) and RDM (Russian Dolls Model). The results show that our model gives significant improvement in terms of delay, throughput and packets loss.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129731483","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 : 2013-05-06DOI: 10.1109/ICTEL.2013.6632124
J. Dromard, R. Khatoun, L. Khoukhi
Most trust and reputation systems in wireless mesh networks are based on the intrusion detection system (IDS) Watchdog. This IDS enables nodes to detect whether their next node on a path flow forwards correctly packets or not by overhearing its transmissions. However, as Watchdog does not consider the packet loss ratio, it can lead to false positives. Indeed, a node can accuse another node of misbehaving whereas in reality it suffers from link loss. In order to overcome this issue, we propose an extension scheme to the Watchdog IDS which enables a node to determine whether it does not overhear its next node due to packet loss issue or due to misbehavior. To reach this goal, we assume that malicious nodes drop both acknowledgements and forwarded packets with different frequencies. Thus, our scheme compares the distribution of a node's acknowledgment with its distribution of forwarded packets of data to detect misbehaving nodes. Furthermore, we extend our scheme so that it enables a node to monitor both its next node and its previous node on a flow path.
{"title":"A Watchdog extension scheme considering packet loss for a reputation system in wireless mesh network","authors":"J. Dromard, R. Khatoun, L. Khoukhi","doi":"10.1109/ICTEL.2013.6632124","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632124","url":null,"abstract":"Most trust and reputation systems in wireless mesh networks are based on the intrusion detection system (IDS) Watchdog. This IDS enables nodes to detect whether their next node on a path flow forwards correctly packets or not by overhearing its transmissions. However, as Watchdog does not consider the packet loss ratio, it can lead to false positives. Indeed, a node can accuse another node of misbehaving whereas in reality it suffers from link loss. In order to overcome this issue, we propose an extension scheme to the Watchdog IDS which enables a node to determine whether it does not overhear its next node due to packet loss issue or due to misbehavior. To reach this goal, we assume that malicious nodes drop both acknowledgements and forwarded packets with different frequencies. Thus, our scheme compares the distribution of a node's acknowledgment with its distribution of forwarded packets of data to detect misbehaving nodes. Furthermore, we extend our scheme so that it enables a node to monitor both its next node and its previous node on a flow path.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127399308","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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