Pub Date : 2001-11-25DOI: 10.1109/GLOCOM.2001.966324
S. Yasukawa, J. Nishikido, K. Hisashi
Advances in wireless broadband communications have continued steadily over the last few years. Both cellular operators and ISP, together with the relevant standardization bodies (e.g. 3GPP, IETF), are eagerly looking at the possibility of employing IP and its mobility and security extensions within their wireless networks. Mobile IPv6 is the most promising technology for developing such an all-IP mobile architecture. There are still several performance defects in this protocol for supporting QoS of real-time wireless traffic, however, because only simple route optimization methods and handoff mechanisms have been proposed. Therefore, innovative route optimization and handoff mechanisms that can handle the quality of service (QoS) of real-time wireless traffic must be developed. A scalable mobility and QoS support mechanism is proposed in this paper. This method optimizes the routing path between a corresponding node and a mobile node by checking the home address' binding cache entry prior to data transmission using RSVP signaling messages. Thus, prior bandwidth reservations at intermediate nodes along the optimal routing path can be achieved. This method also creates a Scalable and flexible routing path that can adapt its routing topology dynamically to account for both changing membership and changing routes. This routing path is constructed by using RSVP's resource reservation capability. Therefore, a fast and smooth handoff for the mobile node can be achieved, while guaranteeing the QoS of real-time traffic. Our proposed schemes are scalable and can be applied to future large-scale mobile IP networks.
{"title":"Scalable mobility and QoS support mechanism for IPv6-based real-time wireless Internet traffic","authors":"S. Yasukawa, J. Nishikido, K. Hisashi","doi":"10.1109/GLOCOM.2001.966324","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.966324","url":null,"abstract":"Advances in wireless broadband communications have continued steadily over the last few years. Both cellular operators and ISP, together with the relevant standardization bodies (e.g. 3GPP, IETF), are eagerly looking at the possibility of employing IP and its mobility and security extensions within their wireless networks. Mobile IPv6 is the most promising technology for developing such an all-IP mobile architecture. There are still several performance defects in this protocol for supporting QoS of real-time wireless traffic, however, because only simple route optimization methods and handoff mechanisms have been proposed. Therefore, innovative route optimization and handoff mechanisms that can handle the quality of service (QoS) of real-time wireless traffic must be developed. A scalable mobility and QoS support mechanism is proposed in this paper. This method optimizes the routing path between a corresponding node and a mobile node by checking the home address' binding cache entry prior to data transmission using RSVP signaling messages. Thus, prior bandwidth reservations at intermediate nodes along the optimal routing path can be achieved. This method also creates a Scalable and flexible routing path that can adapt its routing topology dynamically to account for both changing membership and changing routes. This routing path is constructed by using RSVP's resource reservation capability. Therefore, a fast and smooth handoff for the mobile node can be achieved, while guaranteeing the QoS of real-time traffic. Our proposed schemes are scalable and can be applied to future large-scale mobile IP networks.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121713412","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.966347
Gang Wu, Masugi Inoue, Homare Murakami, Yoshihiro Hase
This paper presents a 156 Mbps ultrahigh-speed wireless LAN in the 38 GHz millimeter (mm)-wave band. The system is the third prototype developed at the Communications Research Laboratory since 1998. Compared with the previous prototypes, the system has the following characteristics: higher speed (156 Mbps), smaller size (volume of radio transceiver < 1000 cc), larger service area (two overlapping basic service sets), and longer transmission distance (the protocol can support a distance of more than two hundred meters). The development is focused on the physical layer and data link control layer, and thus a GMSK-based mm-wave transceiver and an enhanced RS-ISMA (reservation-based slotted idle signal multiple access) are the key development points. This paper covers the prototype system's design, configuration, and implementation.
{"title":"156 Mbps ultrahigh-speed wireless LAN prototype in the 38 GHz band","authors":"Gang Wu, Masugi Inoue, Homare Murakami, Yoshihiro Hase","doi":"10.1109/GLOCOM.2001.966347","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.966347","url":null,"abstract":"This paper presents a 156 Mbps ultrahigh-speed wireless LAN in the 38 GHz millimeter (mm)-wave band. The system is the third prototype developed at the Communications Research Laboratory since 1998. Compared with the previous prototypes, the system has the following characteristics: higher speed (156 Mbps), smaller size (volume of radio transceiver < 1000 cc), larger service area (two overlapping basic service sets), and longer transmission distance (the protocol can support a distance of more than two hundred meters). The development is focused on the physical layer and data link control layer, and thus a GMSK-based mm-wave transceiver and an enhanced RS-ISMA (reservation-based slotted idle signal multiple access) are the key development points. This paper covers the prototype system's design, configuration, and implementation.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115931413","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.965540
K. Quirk
To extend the battery life of a Martian surface unit it is desired to minimize the energy consumed by the surface to orbit communications transceiver. The performance of three different transmission schemes are evaluated in terms of the energy-per-bit required by the transmit power amplifier to achieve a desired energy-per-bit at the receiver. A fixed-power variable-rate transmission scheme is shown to provide the largest savings in energy. Using this as the basis for selecting a multiple access system, a code division multiple access system is presented and its performance is analyzed.
{"title":"An energy efficient CDMA scheme for in-situ communications on Mars","authors":"K. Quirk","doi":"10.1109/GLOCOM.2001.965540","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.965540","url":null,"abstract":"To extend the battery life of a Martian surface unit it is desired to minimize the energy consumed by the surface to orbit communications transceiver. The performance of three different transmission schemes are evaluated in terms of the energy-per-bit required by the transmit power amplifier to achieve a desired energy-per-bit at the receiver. A fixed-power variable-rate transmission scheme is shown to provide the largest savings in energy. Using this as the basis for selecting a multiple access system, a code division multiple access system is presented and its performance is analyzed.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131362906","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.966017
Jung-Won Kim, N. Bambos
In this paper, we investigate power control algorithms for wireless networks utilizing groupwise serial multiuser detection (GSMD), which has recently emerged as an important technology for supporting multirate services over wireless channels. Under GSMD, users are clustered according to their transmission rate/power. Higher rate/power users are detected first, and their signals arc cancelled out before detection of lower rate/power ones, in a sequential manner. We investigate power control algorithms with active link protection for GSMD technologies, which can obtain significant performance gains by utilizing multiuser detection.
{"title":"Power control for multirate wireless networks with groupwise serial multiuser detection","authors":"Jung-Won Kim, N. Bambos","doi":"10.1109/GLOCOM.2001.966017","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.966017","url":null,"abstract":"In this paper, we investigate power control algorithms for wireless networks utilizing groupwise serial multiuser detection (GSMD), which has recently emerged as an important technology for supporting multirate services over wireless channels. Under GSMD, users are clustered according to their transmission rate/power. Higher rate/power users are detected first, and their signals arc cancelled out before detection of lower rate/power ones, in a sequential manner. We investigate power control algorithms with active link protection for GSMD technologies, which can obtain significant performance gains by utilizing multiuser detection.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"160 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132079878","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.966301
Juphil Cho, S. Y. Lee, K. Ahn, H. Baik
Blind equalization of transmission channels is important in communications areas and signal processing applications because it does not need a training sequence, nor does it require a priori channel information. Recently, Tong et al., (1994, 1995), proposed solutions for this problem by exploiting the diversity induced by antenna array or time oversampling, leading to the second order statistics techniques, for example, subspace method, prediction error method, and so on. The linear prediction error method is perhaps the most attractive in practice due to its being insensitive to blind equalizer length mismatch as well as for its simple adaptive filter implementation. Unfortunately, the previous one-step ahead prediction error method is known to be limited in arbitrary delay. In this paper, we induce the optimal delay, and propose an adaptive blind equalizer with multistep linear prediction using the RLS- and LMS-type algorithm. Simulation results are presented to demonstrate the proposed algorithm and to compare it with existing algorithms.
{"title":"Least squares approach to ZF blind equalization using multistep prediction","authors":"Juphil Cho, S. Y. Lee, K. Ahn, H. Baik","doi":"10.1109/GLOCOM.2001.966301","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.966301","url":null,"abstract":"Blind equalization of transmission channels is important in communications areas and signal processing applications because it does not need a training sequence, nor does it require a priori channel information. Recently, Tong et al., (1994, 1995), proposed solutions for this problem by exploiting the diversity induced by antenna array or time oversampling, leading to the second order statistics techniques, for example, subspace method, prediction error method, and so on. The linear prediction error method is perhaps the most attractive in practice due to its being insensitive to blind equalizer length mismatch as well as for its simple adaptive filter implementation. Unfortunately, the previous one-step ahead prediction error method is known to be limited in arbitrary delay. In this paper, we induce the optimal delay, and propose an adaptive blind equalizer with multistep linear prediction using the RLS- and LMS-type algorithm. Simulation results are presented to demonstrate the proposed algorithm and to compare it with existing algorithms.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132109267","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.965101
Yanni Chen, K. Parhi
This paper presents a very low complexity block turbo decoder composed of extended Hamming codes. New efficient complexity reduction algorithms are proposed including simplifying the extrinsic information computation and soft inputs updating algorithm. For performance evaluation, [eHamming (32,26,4)]/sup 2/ and [eHamming (64,57,4)]/sup 2/ block turbo code transmitted over an AWGN channel using BPSK modulation are considered. Extra 0.3 dB to 0.4 dB coding gain is obtained if compared with the scheme proposed in Pyndiah et al., (1996), and the hardware overhead is negligible. The complexity of our new block turbo decoder is about ten times less than that of the near-optimum block turbo decoder with a performance degradation of only 0.5 dB. Other schemes such as reduction of test patterns in the Chase algorithm and memory saving techniques are also presented.
{"title":"A very low complexity block turbo decoder composed of extended Hamming codes","authors":"Yanni Chen, K. Parhi","doi":"10.1109/GLOCOM.2001.965101","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.965101","url":null,"abstract":"This paper presents a very low complexity block turbo decoder composed of extended Hamming codes. New efficient complexity reduction algorithms are proposed including simplifying the extrinsic information computation and soft inputs updating algorithm. For performance evaluation, [eHamming (32,26,4)]/sup 2/ and [eHamming (64,57,4)]/sup 2/ block turbo code transmitted over an AWGN channel using BPSK modulation are considered. Extra 0.3 dB to 0.4 dB coding gain is obtained if compared with the scheme proposed in Pyndiah et al., (1996), and the hardware overhead is negligible. The complexity of our new block turbo decoder is about ten times less than that of the near-optimum block turbo decoder with a performance degradation of only 0.5 dB. Other schemes such as reduction of test patterns in the Chase algorithm and memory saving techniques are also presented.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132208445","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.965660
D. Dardari
This paper presents an analytical model for the evaluation of nonlinear effects in the presence of Gaussian input signals with arbitrary spectrum. A simple relationship between the output signal power spectrum and the nonlinear device characteristic is given. The signal-to-distortion ratio (SDR) is also derived to show the impact of in-band and out-of-band distortion. The methodology is applied to estimate the accuracy of third and fifth-order models for a typical MMIC RF power amplifier.
{"title":"Spectral properties and signal-to-distortion ratio of arbitrary spectrum Gaussian signals in the presence of nonlinearities","authors":"D. Dardari","doi":"10.1109/GLOCOM.2001.965660","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.965660","url":null,"abstract":"This paper presents an analytical model for the evaluation of nonlinear effects in the presence of Gaussian input signals with arbitrary spectrum. A simple relationship between the output signal power spectrum and the nonlinear device characteristic is given. The signal-to-distortion ratio (SDR) is also derived to show the impact of in-band and out-of-band distortion. The methodology is applied to estimate the accuracy of third and fifth-order models for a typical MMIC RF power amplifier.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131246329","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.965651
J. Sýkora
A constant envelope space-time modulation seems to be an attractive option especially for very high frequency and mobile applications because of its resistance to nonlinear distortion. The paper first analyzes the mean squared distance of the constant envelope space-time modulated signal in a Rayleigh slowly flat fading spatial diversity channel with independent coefficients. It is shown that the distance evaluation depends on both the modulator trellis and the distance evaluation trellis. The latter has special properties regarding its free paths. These properties, a critical path and the distance increments behavior, are the basis for the space-time trellis code design. The paper identifies the trellis code design rules minimizing the mean squared distance. The critical path is shown to be the determining factor.
{"title":"Constant envelope space-time modulation trellis code design for Rayleigh flat fading channel","authors":"J. Sýkora","doi":"10.1109/GLOCOM.2001.965651","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.965651","url":null,"abstract":"A constant envelope space-time modulation seems to be an attractive option especially for very high frequency and mobile applications because of its resistance to nonlinear distortion. The paper first analyzes the mean squared distance of the constant envelope space-time modulated signal in a Rayleigh slowly flat fading spatial diversity channel with independent coefficients. It is shown that the distance evaluation depends on both the modulator trellis and the distance evaluation trellis. The latter has special properties regarding its free paths. These properties, a critical path and the distance increments behavior, are the basis for the space-time trellis code design. The paper identifies the trellis code design rules minimizing the mean squared distance. The critical path is shown to be the determining factor.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130999453","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.965885
V. Sharma, P. Purkayastha
We study the stability and performance of a system involving several TCP connections passing through a tandem of RED controlled queues each of which has an incoming exogenous stream. The exogenous stream, which represents the superposition of all incoming UDP connections into a queue, has been modeled as an MMPP stream. We consider both the TCP Tahoe and the TCP Reno versions. We provide the conditions for stability of the system and closed form expressions for the throughput of the TCP connections and the mean sojourn times of the TCP and the exogenous streams. A decomposition approach has been used to simplify computations. These results have implications for bandwidth reservation and providing QoS in the Internet.
{"title":"Performance analysis of TCP connections with RED control and exogenous traffic","authors":"V. Sharma, P. Purkayastha","doi":"10.1109/GLOCOM.2001.965885","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.965885","url":null,"abstract":"We study the stability and performance of a system involving several TCP connections passing through a tandem of RED controlled queues each of which has an incoming exogenous stream. The exogenous stream, which represents the superposition of all incoming UDP connections into a queue, has been modeled as an MMPP stream. We consider both the TCP Tahoe and the TCP Reno versions. We provide the conditions for stability of the system and closed form expressions for the throughput of the TCP connections and the mean sojourn times of the TCP and the exogenous streams. A decomposition approach has been used to simplify computations. These results have implications for bandwidth reservation and providing QoS in the Internet.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131004443","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 : 2001-11-25DOI: 10.1109/GLOCOM.2001.965156
M. O. Damen, N. Beaulieu
Space-time coding is an established technique for combating the impairments of wireless channels by means of the transmit diversity which is obtained by coding the information symbols over M transmit antennas and T symbol periods. Many existing space-time codes have good performance over the wireless channel, however, they offer small data rates compared to the actual capacity of the multi-antenna system. We study some M/spl times/T space-time block codes, for M=2,3,4 and T=2,4, with a rate of M symbols per channel use and a transmit diversity of T over a quasi-static or fast fading channel when using rotated versions of a multidimensional quadratic amplitude modulation with spectral efficiency of 2 bits per symbol. An extension to constellations with a higher spectral efficiency is also considered. We generalize the proposed codes to any number of transmit antennae M and any number of symbol periods T, such that we transmit at a rate of M symbols per channel use, and achieve a transmit diversity of T in fast fading.
{"title":"A study of some space-time codes with rates beyond one symbol per channel use","authors":"M. O. Damen, N. Beaulieu","doi":"10.1109/GLOCOM.2001.965156","DOIUrl":"https://doi.org/10.1109/GLOCOM.2001.965156","url":null,"abstract":"Space-time coding is an established technique for combating the impairments of wireless channels by means of the transmit diversity which is obtained by coding the information symbols over M transmit antennas and T symbol periods. Many existing space-time codes have good performance over the wireless channel, however, they offer small data rates compared to the actual capacity of the multi-antenna system. We study some M/spl times/T space-time block codes, for M=2,3,4 and T=2,4, with a rate of M symbols per channel use and a transmit diversity of T over a quasi-static or fast fading channel when using rotated versions of a multidimensional quadratic amplitude modulation with spectral efficiency of 2 bits per symbol. An extension to constellations with a higher spectral efficiency is also considered. We generalize the proposed codes to any number of transmit antennae M and any number of symbol periods T, such that we transmit at a rate of M symbols per channel use, and achieve a transmit diversity of T in fast fading.","PeriodicalId":346622,"journal":{"name":"GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131199388","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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