Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286357
M. Bergmann, P. Romano, O. Koudelka, M. Wittig
Since space missions have been flown, a proper data return to Earth was inherently required. The complexity level and the number of space experiments have increased over the last decades. As a consequence, higher data rates have been required. The most limiting factor on achievable data rates for interplanetary communications is the distance. It imposes challenges on all parts of the communication system. Communication user and system requirements must be carefully defined to fulfill the mission needs. These requirements are expected to increase in the future. Hence, we studied 13 generic future ESA space mission scenarios comprising 5 Lunar missions, 5 Mars missions, and three missions to special targets (Lagrange point L2, NEO, and the Jovian satellite Europa) based on planned and already flown missions in order to derive communication user and system requirements. These requirements were classified, scaled, adapted and validated by calculations for these missions defined in [1]. Within this paper we will present how communication user and system requirements for future space science missions can be classified, scaled and applied. Therefore, after introducing a proper classification of communication requirements we will present recommendations by means of concrete examples assuming an Asteroid Sample Return mission scenario. Some practical hints will be provided as well.
{"title":"Generic communication user and system requirements for future space science missions","authors":"M. Bergmann, P. Romano, O. Koudelka, M. Wittig","doi":"10.1109/IWSSC.2009.5286357","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286357","url":null,"abstract":"Since space missions have been flown, a proper data return to Earth was inherently required. The complexity level and the number of space experiments have increased over the last decades. As a consequence, higher data rates have been required. The most limiting factor on achievable data rates for interplanetary communications is the distance. It imposes challenges on all parts of the communication system. Communication user and system requirements must be carefully defined to fulfill the mission needs. These requirements are expected to increase in the future. Hence, we studied 13 generic future ESA space mission scenarios comprising 5 Lunar missions, 5 Mars missions, and three missions to special targets (Lagrange point L2, NEO, and the Jovian satellite Europa) based on planned and already flown missions in order to derive communication user and system requirements. These requirements were classified, scaled, adapted and validated by calculations for these missions defined in [1]. Within this paper we will present how communication user and system requirements for future space science missions can be classified, scaled and applied. Therefore, after introducing a proper classification of communication requirements we will present recommendations by means of concrete examples assuming an Asteroid Sample Return mission scenario. Some practical hints will be provided as well.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127251485","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286384
Jaekyoung Ahn, Namgyu Cho, Do-Seob Ahn, Jonghwa Kim
The objective of this paper is to assess the economic feasibilities of International Mobile Telecommunication (IMT)-advanced satellite services in Korea. IMT-Advanced systems allow mobile services that are able to have an always-on access to a wide range of broadcasting and telecommunication networks including advanced mobile service with transparent devices. In this paper, economic aspects of a Fill-in Service and a Two-way S-DMB Service are analyzed; Revenues from the defined services are forecasted and capital expenditure as well as operating expenditure is estimated. To evaluate the profitability of IMT-advanced satellite services, the net present value (NPV), the internal rate of return (IRR) and economic spill-over effects are calculated. The results show that IMT-advanced satellite service is economically justifiable.
{"title":"A study on economic evaluation of IMT-Advanced satellite services in Korea","authors":"Jaekyoung Ahn, Namgyu Cho, Do-Seob Ahn, Jonghwa Kim","doi":"10.1109/IWSSC.2009.5286384","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286384","url":null,"abstract":"The objective of this paper is to assess the economic feasibilities of International Mobile Telecommunication (IMT)-advanced satellite services in Korea. IMT-Advanced systems allow mobile services that are able to have an always-on access to a wide range of broadcasting and telecommunication networks including advanced mobile service with transparent devices. In this paper, economic aspects of a Fill-in Service and a Two-way S-DMB Service are analyzed; Revenues from the defined services are forecasted and capital expenditure as well as operating expenditure is estimated. To evaluate the profitability of IMT-advanced satellite services, the net present value (NPV), the internal rate of return (IRR) and economic spill-over effects are calculated. The results show that IMT-advanced satellite service is economically justifiable.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"155 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126596012","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286350
Anju Pillai, Yim-Fun Hu, P. Chan, Roz Wyatt-Millington, P. Febvre, J. Rivera
This paper is focused on the design of an adaptive Connection Admission Control (CAC) framework for a Multimedia Broadcast Multicast Service (MBMS) compatible satellite system. The main feature of the proposed framework is the ability to maximize the resource utilization by adapting to the link conditions of the users. The link quality of the user may vary depending on the weather condition, user mobility and any other propagation factors. The framework also features the ability to admit a higher priority connection by pre-empting an existing lower priority connection for multimedia traffic with varying bandwidth requirements. The proposed CAC framework is simulated using MATLAB and the performance results are obtained for a mix of multimedia traffic classes such as videostreaming, webbrowsing, netted voice and email.
{"title":"Adaptive Admission Control for MBMS satellite system","authors":"Anju Pillai, Yim-Fun Hu, P. Chan, Roz Wyatt-Millington, P. Febvre, J. Rivera","doi":"10.1109/IWSSC.2009.5286350","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286350","url":null,"abstract":"This paper is focused on the design of an adaptive Connection Admission Control (CAC) framework for a Multimedia Broadcast Multicast Service (MBMS) compatible satellite system. The main feature of the proposed framework is the ability to maximize the resource utilization by adapting to the link conditions of the users. The link quality of the user may vary depending on the weather condition, user mobility and any other propagation factors. The framework also features the ability to admit a higher priority connection by pre-empting an existing lower priority connection for multimedia traffic with varying bandwidth requirements. The proposed CAC framework is simulated using MATLAB and the performance results are obtained for a mix of multimedia traffic classes such as videostreaming, webbrowsing, netted voice and email.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"3 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123637809","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286338
Efthymios Koutsogiannis, Giorgos Papastergiou, V. Tsaoussidis
Space communications enter a new era where a multihop architecture is being exploited and an increasing number of alternative communication paths may be available. Current space applications, such as CFDP for file transfer, rely on static routing and can not efficiently perform in these challenging environments. The most promising solution is the emerging Delay Tolerant Networking (DTN) Architecture and the accompanying Bundle Protocol which allow for reliable store-and-forward message switching, custody transfer and dynamic routing. However, a space-oriented file transfer protocol for DTN is required. In this work, we integrate CFDP with ION (a Bundle Protocol implementation produced by the Jet Propulsion Laboratory) and evaluate its performance in a DTN testbed.
{"title":"Evaluation of CCSDS file delivery protocol over Delay Tolerant Networks","authors":"Efthymios Koutsogiannis, Giorgos Papastergiou, V. Tsaoussidis","doi":"10.1109/IWSSC.2009.5286338","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286338","url":null,"abstract":"Space communications enter a new era where a multihop architecture is being exploited and an increasing number of alternative communication paths may be available. Current space applications, such as CFDP for file transfer, rely on static routing and can not efficiently perform in these challenging environments. The most promising solution is the emerging Delay Tolerant Networking (DTN) Architecture and the accompanying Bundle Protocol which allow for reliable store-and-forward message switching, custody transfer and dynamic routing. However, a space-oriented file transfer protocol for DTN is required. In this work, we integrate CFDP with ION (a Bundle Protocol implementation produced by the Jet Propulsion Laboratory) and evaluate its performance in a DTN testbed.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121644064","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286330
H. Skinnemoen, Alexandre Tosoni de Mentzingen
This paper investigates the latest status of DVB-RCS as well as the impact of the BRASIL project support for DVB-RCS in Latin America. We analyze the situation in general and specifically assess the situation for the next generation DVB-RCS work both in terms of input to the standardization process and in terms of impact of the future standard DVB-RCS system as it is currently know to be. The key focus is on how DVB-RCS best can continue to support the bridging of the digital divide.
{"title":"Latest impact of supporting DVB-RCS for rural America","authors":"H. Skinnemoen, Alexandre Tosoni de Mentzingen","doi":"10.1109/IWSSC.2009.5286330","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286330","url":null,"abstract":"This paper investigates the latest status of DVB-RCS as well as the impact of the BRASIL project support for DVB-RCS in Latin America. We analyze the situation in general and specifically assess the situation for the next generation DVB-RCS work both in terms of input to the standardization process and in terms of impact of the future standard DVB-RCS system as it is currently know to be. The key focus is on how DVB-RCS best can continue to support the bridging of the digital divide.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121847671","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286395
H. Gam, D. Oh, Do-Seob Ahn
This paper addresses the analysis of the interference produced between the Non-GSO satellite system and FS system operating in the same frequency. Simulations performed for two different downlink interference scenarios. The interference analysis results are given in terms of epfd and I/N. In the first scenario, simulation results show that the amount of interference that was calculated by proposed method is larger than typical method. This result can be used to define the effective criteria for protection FS system from aggregation interference by Non-GSO satellite system. The second scenario calculates the interference of Non-GSO satellite system earth station by the FS link according to radius of protection area. The presented results can be used to design FS systems minimizing interference to earth station.
{"title":"Effective method to assess the impact of interference between Non-GSO system and fixed service","authors":"H. Gam, D. Oh, Do-Seob Ahn","doi":"10.1109/IWSSC.2009.5286395","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286395","url":null,"abstract":"This paper addresses the analysis of the interference produced between the Non-GSO satellite system and FS system operating in the same frequency. Simulations performed for two different downlink interference scenarios. The interference analysis results are given in terms of epfd and I/N. In the first scenario, simulation results show that the amount of interference that was calculated by proposed method is larger than typical method. This result can be used to define the effective criteria for protection FS system from aggregation interference by Non-GSO satellite system. The second scenario calculates the interference of Non-GSO satellite system earth station by the FS link according to radius of protection area. The presented results can be used to design FS systems minimizing interference to earth station.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123211496","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286385
F. Stathopoulos, P. Constantinou, A. Panagopoulos
In this paper, we investigate how the aircraft flow field affects the laser beam wavefront in an optical point-topoint link. We study various flow fields highlighting the different distortions that are created. The subject of the manuscript is twofold. Firstly, we study the steady laminar incompressible flow around an ellipse and secondly we assume a sphere as a flying object and we present simulated results for various types of flow, from laminar to turbulent, as the speed of the sphere is increasing. Furthermore we examine the performance of the distortions along the altitude, when density is getting smaller. Employing the above methology, we have presented one ‘realistic’ simulation scenario of an aircraft that communicates through an optical link.
{"title":"Impact of various flow-fields on laser beam propagation","authors":"F. Stathopoulos, P. Constantinou, A. Panagopoulos","doi":"10.1109/IWSSC.2009.5286385","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286385","url":null,"abstract":"In this paper, we investigate how the aircraft flow field affects the laser beam wavefront in an optical point-topoint link. We study various flow fields highlighting the different distortions that are created. The subject of the manuscript is twofold. Firstly, we study the steady laminar incompressible flow around an ellipse and secondly we assume a sphere as a flying object and we present simulated results for various types of flow, from laminar to turbulent, as the speed of the sphere is increasing. Furthermore we examine the performance of the distortions along the altitude, when density is getting smaller. Employing the above methology, we have presented one ‘realistic’ simulation scenario of an aircraft that communicates through an optical link.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"396 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120976226","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286414
R. Schwarz, A. Knopp, B. Lankl
The impact of atmospheric impairments on the bandwidth efficiency of Multiple-Input Multiple-Output (MIMO) geostationary satellite links is investigated theoretically. In particular we analyze the impairments caused by precipitation because especially rain and wet snow are the most severe atmospheric impact factors degrading the channel capacity. We focus on Line-of-Sight (LOS) MIMO links that are shaped for optimum channel capacity. For that purpose the link optimization suggested in [1] is applied. Our investigations reveal to which extent the MIMO satellite channel capacity is affected by atmospheric signal attenuation and signal phase disturbances, which might reduce the number and strength of spatial subchannels (eigenmodes). Especially the impact of signal attenuation is investigated by means of probabilistic analyses, quantifying the amount and percentage of time which the link capacity degradation exceeds a particular value. Altogether we conclude that, although a loss of capacity cannot be avoided in general, MIMO systems outperform Single-Input Single-Output (SISO) designs by far, not only in terms of bandwidth efficiency but also in link reliability.
{"title":"The channel capacity of MIMO satellite links in a fading environment: A probabilistic analysis","authors":"R. Schwarz, A. Knopp, B. Lankl","doi":"10.1109/IWSSC.2009.5286414","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286414","url":null,"abstract":"The impact of atmospheric impairments on the bandwidth efficiency of Multiple-Input Multiple-Output (MIMO) geostationary satellite links is investigated theoretically. In particular we analyze the impairments caused by precipitation because especially rain and wet snow are the most severe atmospheric impact factors degrading the channel capacity. We focus on Line-of-Sight (LOS) MIMO links that are shaped for optimum channel capacity. For that purpose the link optimization suggested in [1] is applied. Our investigations reveal to which extent the MIMO satellite channel capacity is affected by atmospheric signal attenuation and signal phase disturbances, which might reduce the number and strength of spatial subchannels (eigenmodes). Especially the impact of signal attenuation is investigated by means of probabilistic analyses, quantifying the amount and percentage of time which the link capacity degradation exceeds a particular value. Altogether we conclude that, although a loss of capacity cannot be avoided in general, MIMO systems outperform Single-Input Single-Output (SISO) designs by far, not only in terms of bandwidth efficiency but also in link reliability.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128341929","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286369
Hui Luo, Y. Ma, B. Evans
This paper presents a novel spectrally efficient relaying scheme for satellite broadcast networks, where two selective decode-and-forward (SDF) relays are employed to improve the performance of satellite-to-destination link. In the proposed scheme, the satellite continuously transmits the signal through an allocated satellite frequency-band. The relaying stations operate in the half-duplex mode, and share the same frequency band with the satellite to improve the spectral efficiency. A log-likelihood detector is employed at both relays and the destination to conduct joint signal detection and co-channel interference cancellation. Computer simulations are carried out to compare the proposed scheme with the conventional orthogonal-relaying scheme in various channel environments. It is shown that the proposed scheme improves by 50% spectral efficiency for loss of 1.5 – 5 dB in performance at the high-Eb/No range (≫ 15 dB) for the uncoded communication, and for loss of 0.7 – 1.2 dB in performance at the high-Eb/No range (≫ 12 dB) for the coded case, respectively.
{"title":"A spectral efficient decode-and-forward relaying scheme for satellite broadcast networks","authors":"Hui Luo, Y. Ma, B. Evans","doi":"10.1109/IWSSC.2009.5286369","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286369","url":null,"abstract":"This paper presents a novel spectrally efficient relaying scheme for satellite broadcast networks, where two selective decode-and-forward (SDF) relays are employed to improve the performance of satellite-to-destination link. In the proposed scheme, the satellite continuously transmits the signal through an allocated satellite frequency-band. The relaying stations operate in the half-duplex mode, and share the same frequency band with the satellite to improve the spectral efficiency. A log-likelihood detector is employed at both relays and the destination to conduct joint signal detection and co-channel interference cancellation. Computer simulations are carried out to compare the proposed scheme with the conventional orthogonal-relaying scheme in various channel environments. It is shown that the proposed scheme improves by 50% spectral efficiency for loss of 1.5 – 5 dB in performance at the high-Eb/No range (≫ 15 dB) for the uncoded communication, and for loss of 0.7 – 1.2 dB in performance at the high-Eb/No range (≫ 12 dB) for the coded case, respectively.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133136631","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 : 2009-10-13DOI: 10.1109/IWSSC.2009.5286393
F. Nadeem, E. Leitgeb, M. S. Awan, G. Kandus
The benefits of Free space Optics (FSO) motivates to use it for future high data rate demanding communication applications. However, widespread growth of the technology has been hampered by reduced availability due to weather influences on the link. The alternate is to use back up RF link for improving the availability. But it requires intelligent switching back and forth between two links. The forward prediction of the received signal strength can greatly improve the performance of such hybrid network. The forward prediction approach has been analyzed using measured FSO attenuation data. The results are analyzed in terms of mean square error.
{"title":"Forward prediction of FSO received signal for FSO/RF hybrid network","authors":"F. Nadeem, E. Leitgeb, M. S. Awan, G. Kandus","doi":"10.1109/IWSSC.2009.5286393","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286393","url":null,"abstract":"The benefits of Free space Optics (FSO) motivates to use it for future high data rate demanding communication applications. However, widespread growth of the technology has been hampered by reduced availability due to weather influences on the link. The alternate is to use back up RF link for improving the availability. But it requires intelligent switching back and forth between two links. The forward prediction of the received signal strength can greatly improve the performance of such hybrid network. The forward prediction approach has been analyzed using measured FSO attenuation data. The results are analyzed in terms of mean square error.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134405385","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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