Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936254
J. Mwangoka, P. Marques, Jonathan Rodriguez
The regulatory scenario in Europe is very diverse, and hence innovative solutions to address harmonization and coexistence issues become crucial for the successful exploitation of the TV white spaces (TVWS) among member states. This paper introduces the approach of the European Commission funded COGEU (COgnitive radio systems for efficient sharing of TV white spaces in EUropean context) project in exploiting the TVWS. COGEU proposes a bicameral (national) geolocation database separating bands for commons usage and for secondary spectrum trading. The commons bands are for access without the need for guaranteed quality of service (QoS), while secondary trading bands are for access with a need for guaranteed QoS. Temporary exclusive rights for operating in the TVWS may be bought from a broker. Details of the operation of the broker are given with examples on usage scenarios.
{"title":"Exploiting TV white spaces in Europe: The COGEU approach","authors":"J. Mwangoka, P. Marques, Jonathan Rodriguez","doi":"10.1109/DYSPAN.2011.5936254","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936254","url":null,"abstract":"The regulatory scenario in Europe is very diverse, and hence innovative solutions to address harmonization and coexistence issues become crucial for the successful exploitation of the TV white spaces (TVWS) among member states. This paper introduces the approach of the European Commission funded COGEU (COgnitive radio systems for efficient sharing of TV white spaces in EUropean context) project in exploiting the TVWS. COGEU proposes a bicameral (national) geolocation database separating bands for commons usage and for secondary spectrum trading. The commons bands are for access without the need for guaranteed quality of service (QoS), while secondary trading bands are for access with a need for guaranteed QoS. Temporary exclusive rights for operating in the TVWS may be bought from a broker. Details of the operation of the broker are given with examples on usage scenarios.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127883509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936250
H. Harada, H. Fujii, S. Miura, H. Kayama, Y. Okano, T. Imai
An important and widely used detection technique is cyclostationarity-based feature detection because the method does not require prior information such as the signal bandwidth or frame format, and time and frequency synchronization are likewise not required. The problem with conventional cyclostationarity-based feature detection is that the detection probability of weak signals degrades if multiple signals with different received-power levels are captured simultaneously. One way to address this problem is to use a multiple signal identification method in which appropriate notches suppress the effects of other signals. In this paper, we evaluate a multiple signal identification method based on test bed experiments. In order to evaluate the method in a realistic environment as a field test, a spatial channel emulator and an antenna of a mock terminal are applied to the test bed. The results reveal the effectiveness of the methodology in realistic spectrum sharing scenarios.
{"title":"Experimental evaluation of cyclostationarity-based multiple signal identification method by using spatial channel emulator","authors":"H. Harada, H. Fujii, S. Miura, H. Kayama, Y. Okano, T. Imai","doi":"10.1109/DYSPAN.2011.5936250","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936250","url":null,"abstract":"An important and widely used detection technique is cyclostationarity-based feature detection because the method does not require prior information such as the signal bandwidth or frame format, and time and frequency synchronization are likewise not required. The problem with conventional cyclostationarity-based feature detection is that the detection probability of weak signals degrades if multiple signals with different received-power levels are captured simultaneously. One way to address this problem is to use a multiple signal identification method in which appropriate notches suppress the effects of other signals. In this paper, we evaluate a multiple signal identification method based on test bed experiments. In order to evaluate the method in a realistic environment as a field test, a spatial channel emulator and an antenna of a mock terminal are applied to the test bed. The results reveal the effectiveness of the methodology in realistic spectrum sharing scenarios.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123648207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936260
H. Zhou, T. Ratnarajah, Ying-Chang Liang
We consider a peer-to-peer cognitive radio (CR) network with single primary user and multiple secondary users. We propose an interference alignment technique for this network, and show that desired secondary user performances can be archived without degrading the primary user performance for both single and multiple antenna networks. For the multiple antenna networks, we optimize both the precoding vectors and power allocation to enhance the secondary user rates using a gradient method. Numerical results are given for primary and secondary users rates, which show that the proposed precoding vectors and power allocation algorithm enhance the performance of the CR network. Hence the proposed interference alignment scheme significantly enhances the spectrum efficiency.
{"title":"On secondary network interference alignment in cognitive radio","authors":"H. Zhou, T. Ratnarajah, Ying-Chang Liang","doi":"10.1109/DYSPAN.2011.5936260","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936260","url":null,"abstract":"We consider a peer-to-peer cognitive radio (CR) network with single primary user and multiple secondary users. We propose an interference alignment technique for this network, and show that desired secondary user performances can be archived without degrading the primary user performance for both single and multiple antenna networks. For the multiple antenna networks, we optimize both the precoding vectors and power allocation to enhance the secondary user rates using a gradient method. Numerical results are given for primary and secondary users rates, which show that the proposed precoding vectors and power allocation algorithm enhance the performance of the CR network. Hence the proposed interference alignment scheme significantly enhances the spectrum efficiency.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127737175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936262
Y. Miar, T. Aboulnasr, A. Yongaçoğlu, T. Aboulnasr
Four simplified discrete Fourier transform (SDFT)-based spectrum sensing methods are introduced for power spectral density (PSD) estimation for cognitive radio (CR). The SDFT-based spectrum sensing techniques are less computationally complex than DFT techniques since no multiplications are required in the time-to-frequency domain conversion process. The simulation results and mathematical analyses indicate that the performance of the SDFT-based spectrum sensing method is comparable to that of the DFT-based one when the received signal spectrum is lightly occupied.
{"title":"Simplified DFT: A novel method for wideband spectrum sensing in cognitive radio","authors":"Y. Miar, T. Aboulnasr, A. Yongaçoğlu, T. Aboulnasr","doi":"10.1109/DYSPAN.2011.5936262","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936262","url":null,"abstract":"Four simplified discrete Fourier transform (SDFT)-based spectrum sensing methods are introduced for power spectral density (PSD) estimation for cognitive radio (CR). The SDFT-based spectrum sensing techniques are less computationally complex than DFT techniques since no multiplications are required in the time-to-frequency domain conversion process. The simulation results and mathematical analyses indicate that the performance of the SDFT-based spectrum sensing method is comparable to that of the DFT-based one when the received signal spectrum is lightly occupied.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121047865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936267
C. Bonnet, D. Câmara, R. Ghaddab, A. Hayar, L. Iacobelli, F. Kaltenberger, R. Knopp, B. Mercier, N. Nikaein, D. Nussbaum, E. Yilmaz, B. Zayen
This demonstration1 highlights the capabilities of the OpenAirInterface platform in terms of Agile RF spectrum-access and rapidly-deployable networking technologies. With respect to application scenarios, the latter target broadband public-safety communications. We demonstrate the real-time baseband and RF capabilities of the platform components as well as the methodologies used for large-scale system emulation on PC-based computing platforms.
{"title":"OpenAirInterface and agile spectrum access","authors":"C. Bonnet, D. Câmara, R. Ghaddab, A. Hayar, L. Iacobelli, F. Kaltenberger, R. Knopp, B. Mercier, N. Nikaein, D. Nussbaum, E. Yilmaz, B. Zayen","doi":"10.1109/DYSPAN.2011.5936267","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936267","url":null,"abstract":"This demonstration1 highlights the capabilities of the OpenAirInterface platform in terms of Agile RF spectrum-access and rapidly-deployable networking technologies. With respect to application scenarios, the latter target broadband public-safety communications. We demonstrate the real-time baseband and RF capabilities of the platform components as well as the methodologies used for large-scale system emulation on PC-based computing platforms.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120867222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936259
J. C. O'Sullivan, Paolo Di Francesco, Uchenna K. Anyanwu, L. Dasilva, A. B. Mackenzie
This paper presents the implementation and experimental evaluation of a MAC protocol designed to overcome some of the limitations of affordable and widely-deployed software defined radio hardware. We propose a modified Aloha-based MAC protocol with implicit acknowledgements to mitigate the impact of intra-flow collisions in multi-hop wireless communications. We experimentally observe a significant improvement in throughput and delay through simple modifications to the MAC protocol, tailoring it to the timing constraints of the USRP1.
{"title":"Multi-hop MAC implementations for affordable SDR hardware","authors":"J. C. O'Sullivan, Paolo Di Francesco, Uchenna K. Anyanwu, L. Dasilva, A. B. Mackenzie","doi":"10.1109/DYSPAN.2011.5936259","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936259","url":null,"abstract":"This paper presents the implementation and experimental evaluation of a MAC protocol designed to overcome some of the limitations of affordable and widely-deployed software defined radio hardware. We propose a modified Aloha-based MAC protocol with implicit acknowledgements to mitigate the impact of intra-flow collisions in multi-hop wireless communications. We experimentally observe a significant improvement in throughput and delay through simple modifications to the MAC protocol, tailoring it to the timing constraints of the USRP1.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121470331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936199
Anil Kumar Chorppath, T. Alpcan, H. Boche
Multi-carrier wireless schemes and systems such as Orthogonal Frequency Division Multiplexing (OFDM), cognitive radios, and femtocells play an important role for efficient power and spectrum utilization. In uplink transmissions of these systems, independent and autonomous mobile users may act selfishly in order to get a higher share of available resources, which is encountered by a pricing mechanism that penalizes the interference they create. Specifically, the mobile users strategically decide on their power levels to minimize their cost which is the difference between their utilities based on Shannon capacity and payments. The base station acts as a mechanism designer to ensure that certain global objectives are satisfied when allocating resources. In this paper, we consider two such objectives: one is sum of user utility maximization and the other one is operator revenue maximization based on the prices charged to users, which coincidentally acts as the coupling factor between user and designer optimization problems. We analyze first the single carrier case as a starting point, which we immediately extend to multi carriers. We next formulate the operator revenue maximization problem using the same framework. Numerical simulations illustrate the mechanism developed and show the convergence of power and price levels of the users.
{"title":"Pricing mechanisms for multi-carrier wireless systems","authors":"Anil Kumar Chorppath, T. Alpcan, H. Boche","doi":"10.1109/DYSPAN.2011.5936199","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936199","url":null,"abstract":"Multi-carrier wireless schemes and systems such as Orthogonal Frequency Division Multiplexing (OFDM), cognitive radios, and femtocells play an important role for efficient power and spectrum utilization. In uplink transmissions of these systems, independent and autonomous mobile users may act selfishly in order to get a higher share of available resources, which is encountered by a pricing mechanism that penalizes the interference they create. Specifically, the mobile users strategically decide on their power levels to minimize their cost which is the difference between their utilities based on Shannon capacity and payments. The base station acts as a mechanism designer to ensure that certain global objectives are satisfied when allocating resources. In this paper, we consider two such objectives: one is sum of user utility maximization and the other one is operator revenue maximization based on the prices charged to users, which coincidentally acts as the coupling factor between user and designer optimization problems. We analyze first the single carrier case as a starting point, which we immediately extend to multi carriers. We next formulate the operator revenue maximization problem using the same framework. Numerical simulations illustrate the mechanism developed and show the convergence of power and price levels of the users.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116889827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936241
C. Sum, F. Kojima, H. Harada
This paper presents the overview on coexistence of homogeneous and heterogeneous systems for the IEEE 802.15.4g Smart Utility Network (SUN), a low rate wireless personal area network (WPAN) standard for advanced utility service. The 802.15.4g specifies three alternative physical (PHY) layer designs, thus having multiple homogeneous systems within the SUN system. The three homogeneous systems are allocated across shared frequency bands dependent on different regulatory domains. Besides coexistence for homogeneous systems, the SUN system is also sharing several frequency bands with multiple heterogeneous systems across various other 802 standards. Understanding the details of these coexisting dissimilar systems is an essential step to creating a harmonious radio environment. Therefore, this paper provides the outline of the coexisting homogeneous and heterogeneous systems, as well as the corresponding frequency bands that are allocated in different regulatory domains. Secondly, the overview on the coexistence mechanisms applicable in the 802.15.4g system is presented. Thirdly, coexistence analysis is performed on two dissimilar systems, where the performance degradation of a victim system is evaluated in the presence of an interferer. As a collective result, it is shown that with victim-interferer separation of beyond approximately 30m, dissimilar systems are able to coexist even without higher layer coexistence mechanisms.
{"title":"Coexistence of homogeneous and heterogeneous systems for IEEE 802.15.4g smart utility networks","authors":"C. Sum, F. Kojima, H. Harada","doi":"10.1109/DYSPAN.2011.5936241","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936241","url":null,"abstract":"This paper presents the overview on coexistence of homogeneous and heterogeneous systems for the IEEE 802.15.4g Smart Utility Network (SUN), a low rate wireless personal area network (WPAN) standard for advanced utility service. The 802.15.4g specifies three alternative physical (PHY) layer designs, thus having multiple homogeneous systems within the SUN system. The three homogeneous systems are allocated across shared frequency bands dependent on different regulatory domains. Besides coexistence for homogeneous systems, the SUN system is also sharing several frequency bands with multiple heterogeneous systems across various other 802 standards. Understanding the details of these coexisting dissimilar systems is an essential step to creating a harmonious radio environment. Therefore, this paper provides the outline of the coexisting homogeneous and heterogeneous systems, as well as the corresponding frequency bands that are allocated in different regulatory domains. Secondly, the overview on the coexistence mechanisms applicable in the 802.15.4g system is presented. Thirdly, coexistence analysis is performed on two dissimilar systems, where the performance degradation of a victim system is evaluated in the presence of an interferer. As a collective result, it is shown that with victim-interferer separation of beyond approximately 30m, dissimilar systems are able to coexist even without higher layer coexistence mechanisms.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133666155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936238
Andrew Stirling
Current approaches to managing spectrum are polarized and inflexible. They underplay the value that license exemption and opportunistic access could deliver. This paper describes how new geolocation database technology could enable the use of hybrid models combining the advantages of licensing with those of license exemption. It considers how such models could help accelerate infrastructure investment for wireless broadband access, as well as facilitating innovation in wireless technology and services.
{"title":"Exploiting hybrid models for spectrum access: Building on the capabilities of geolocation databases","authors":"Andrew Stirling","doi":"10.1109/DYSPAN.2011.5936238","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936238","url":null,"abstract":"Current approaches to managing spectrum are polarized and inflexible. They underplay the value that license exemption and opportunistic access could deliver. This paper describes how new geolocation database technology could enable the use of hybrid models combining the advantages of licensing with those of license exemption. It considers how such models could help accelerate infrastructure investment for wireless broadband access, as well as facilitating innovation in wireless technology and services.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132172013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-03DOI: 10.1109/DYSPAN.2011.5936239
Juan D. Deaton, R. Irwin, L. Dasilva
As early as 2014, wireless network operators' spectral capacity will be overwhelmed by the demand brought on by new devices and applications. To augment capacity and meet this demand, operators may choose to deploy a Dynamic Spectrum Access (DSA) overlay. The signaling and functionality required by such an overlay have not yet been fully considered in the architecture of the planned Long Term Evolution Advanced (LTE+) networks. This paper presents a Spectrum Accountability framework to be integrated into LTE+ architectures, defining specific element functionality, protocol interfaces, and signaling flow diagrams required to enforce the rights and responsibilities of primary and secondary users. We also quantify, through simulation, the benefits of using DSA channels to augment capacity. The framework proposed here may serve as a guide in the development of future LTE+ network standards that account for DSA.
{"title":"The effects of a Dynamic Spectrum Access overlay in LTE-Advanced networks","authors":"Juan D. Deaton, R. Irwin, L. Dasilva","doi":"10.1109/DYSPAN.2011.5936239","DOIUrl":"https://doi.org/10.1109/DYSPAN.2011.5936239","url":null,"abstract":"As early as 2014, wireless network operators' spectral capacity will be overwhelmed by the demand brought on by new devices and applications. To augment capacity and meet this demand, operators may choose to deploy a Dynamic Spectrum Access (DSA) overlay. The signaling and functionality required by such an overlay have not yet been fully considered in the architecture of the planned Long Term Evolution Advanced (LTE+) networks. This paper presents a Spectrum Accountability framework to be integrated into LTE+ architectures, defining specific element functionality, protocol interfaces, and signaling flow diagrams required to enforce the rights and responsibilities of primary and secondary users. We also quantify, through simulation, the benefits of using DSA channels to augment capacity. The framework proposed here may serve as a guide in the development of future LTE+ network standards that account for DSA.","PeriodicalId":119856,"journal":{"name":"2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134266410","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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