Pub Date : 2011-12-01DOI: 10.1109/ISCIT.2011.6089717
P. Xiao, W. Yin, R. Tafazolli, S. Shaker
In this paper, we study an enhanced subspace based approach for the mitigation of multiple access interference (MAI) in direct-sequence code-division multiple-access (DS-CDMA) systems over frequency-selective channels. Blind multiuser detection based on signal subspace estimation is of special interest in mitigating MAI in CDMA systems since it is impractical to assume perfect knowledge of parameters such as spreading codes, time delays and amplitudes of all the users in a rapidly changing mobile environment. We develop a new blind multiuser detection scheme which only needs the priori knowledge of the signature waveform and timing of the user of interest. By exploiting the improper nature of multiple access interference (MAI) and intersymbol interference (ISI), the enhanced detector shows clear superiority to the conventional subspace-based blind multiuser detector. The performance advantages are shown to be more obvious in heavily loaded systems when the number of active users is large.
{"title":"Enhanced subspaced approach to interference mitigation","authors":"P. Xiao, W. Yin, R. Tafazolli, S. Shaker","doi":"10.1109/ISCIT.2011.6089717","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089717","url":null,"abstract":"In this paper, we study an enhanced subspace based approach for the mitigation of multiple access interference (MAI) in direct-sequence code-division multiple-access (DS-CDMA) systems over frequency-selective channels. Blind multiuser detection based on signal subspace estimation is of special interest in mitigating MAI in CDMA systems since it is impractical to assume perfect knowledge of parameters such as spreading codes, time delays and amplitudes of all the users in a rapidly changing mobile environment. We develop a new blind multiuser detection scheme which only needs the priori knowledge of the signature waveform and timing of the user of interest. By exploiting the improper nature of multiple access interference (MAI) and intersymbol interference (ISI), the enhanced detector shows clear superiority to the conventional subspace-based blind multiuser detector. The performance advantages are shown to be more obvious in heavily loaded systems when the number of active users is large.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124709702","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089744
O. C. Kwon, H. Oh, Hwangjun Song, GyeongCheol Lee
In this work, we present an effective QoS routing algorithm based on the IEEE 802.11 multi-rate for video streaming over mobile ad hoc networks. The proposed routing algorithm is designed to minimize the consumed timeslots while guaranteeing the required timeslots at all the pairs of adjacent nodes over the route and the contention neighbors of these nodes to support the route. Furthermore, the proposed routing algorithm can distribute the network loads well over the entire network. This technology is essential because video streaming applications require stringent QoS. Experimental results are presented to show the performance of the proposed routing algorithm.
{"title":"QoS routing algorithm consuming minimum overall timeslots for video streaming over MANET","authors":"O. C. Kwon, H. Oh, Hwangjun Song, GyeongCheol Lee","doi":"10.1109/ISCIT.2011.6089744","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089744","url":null,"abstract":"In this work, we present an effective QoS routing algorithm based on the IEEE 802.11 multi-rate for video streaming over mobile ad hoc networks. The proposed routing algorithm is designed to minimize the consumed timeslots while guaranteeing the required timeslots at all the pairs of adjacent nodes over the route and the contention neighbors of these nodes to support the route. Furthermore, the proposed routing algorithm can distribute the network loads well over the entire network. This technology is essential because video streaming applications require stringent QoS. Experimental results are presented to show the performance of the proposed routing algorithm.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129508235","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6092183
M. Hashizume, Yutaka Hata, H. Yotsuyanagi, Y. Miura
In this paper, we propose a supply current testable resistor string DAC of decoder type whose area overhead is small and a supply current test method. Open defects and short ones in the DAC can be detected by the test method with about 50% of the exhausted test vectors. It is shown by some experiments that most of the targeted defects in our testable DACs of 4 and 8 bits can be detected by the test method.
{"title":"A supply current testable register string DAC of decoder type","authors":"M. Hashizume, Yutaka Hata, H. Yotsuyanagi, Y. Miura","doi":"10.1109/ISCIT.2011.6092183","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092183","url":null,"abstract":"In this paper, we propose a supply current testable resistor string DAC of decoder type whose area overhead is small and a supply current test method. Open defects and short ones in the DAC can be detected by the test method with about 50% of the exhausted test vectors. It is shown by some experiments that most of the targeted defects in our testable DACs of 4 and 8 bits can be detected by the test method.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128332221","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089720
Xiaojing Huang, Y. Guo, Jay Au, Au
In many communications and signal processing applications, phase information carried on Gaussian distributed reference signals is often required for various purposes, such as the carrier frequency offset estimation in orthogonal frequency division multiplexing (OFDM) systems. The performance of phase estimation is usually measured by the mean square error (MSE) which is often infeasible to obtain. Instead, the Cramér-Rao Bound (CRB) and modified Cramér-Rao Bound (MCRB) are used to give lower MSE bounds for the phase estimation. This paper presents closed-form MSE approximations for estimating phase information from Gaussian reference signals, which provide better indications of the MSE performance than the MCRB. It is also shown that the MCRB is only attainable at high signal-to-noise ratios and with large number of observed signal samples. Simulated and analytical results are compared to demonstrate the accuracy and efficiency of the derived MSE formulas.
{"title":"Closed-form MSE performance for phase estimation from Gaussian reference signals","authors":"Xiaojing Huang, Y. Guo, Jay Au, Au","doi":"10.1109/ISCIT.2011.6089720","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089720","url":null,"abstract":"In many communications and signal processing applications, phase information carried on Gaussian distributed reference signals is often required for various purposes, such as the carrier frequency offset estimation in orthogonal frequency division multiplexing (OFDM) systems. The performance of phase estimation is usually measured by the mean square error (MSE) which is often infeasible to obtain. Instead, the Cramér-Rao Bound (CRB) and modified Cramér-Rao Bound (MCRB) are used to give lower MSE bounds for the phase estimation. This paper presents closed-form MSE approximations for estimating phase information from Gaussian reference signals, which provide better indications of the MSE performance than the MCRB. It is also shown that the MCRB is only attainable at high signal-to-noise ratios and with large number of observed signal samples. Simulated and analytical results are compared to demonstrate the accuracy and efficiency of the derived MSE formulas.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128469947","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6092160
K. Obaidullah, C. Siriteanu, S. Yoshizawa, Y. Miyanaga
For multiple-input/multiple-output (MIMO) wireless communications systems employing spatial multiplexing transmission we evaluate the convergence performance of genetic algorithm (GA)-based detection against the maximum-likelihood (ML) approach. We consider transmit-correlated Rayleigh and Rician fading with Laplacian power azimuth spectrum. The values of the azimuth spread (AS) and Rician K-factor are selected according to the measurement-based WINNER II channel models, for several relevant scenario types. We consider the effect on GA convergence speed and population size requirements of the following: number of antennas, modulation constellation size, scenario (i.e., AS and K values), and rank of the deterministic component of the channel matrix. We find that the GA population size needs to be carefully adjusted to the antenna geometry and modulation constellation in order to maintain fast convergence. On the other hand, changes in the channel fading type and geometry do not appear to affect GA convergence. GA is shown to achieve ML-like performance, possibly for lower complexity, i.e., more efficient hardware and power usage.
{"title":"Evaluation of genetic algorithm-based detection for correlated MIMO fading channels","authors":"K. Obaidullah, C. Siriteanu, S. Yoshizawa, Y. Miyanaga","doi":"10.1109/ISCIT.2011.6092160","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092160","url":null,"abstract":"For multiple-input/multiple-output (MIMO) wireless communications systems employing spatial multiplexing transmission we evaluate the convergence performance of genetic algorithm (GA)-based detection against the maximum-likelihood (ML) approach. We consider transmit-correlated Rayleigh and Rician fading with Laplacian power azimuth spectrum. The values of the azimuth spread (AS) and Rician K-factor are selected according to the measurement-based WINNER II channel models, for several relevant scenario types. We consider the effect on GA convergence speed and population size requirements of the following: number of antennas, modulation constellation size, scenario (i.e., AS and K values), and rank of the deterministic component of the channel matrix. We find that the GA population size needs to be carefully adjusted to the antenna geometry and modulation constellation in order to maintain fast convergence. On the other hand, changes in the channel fading type and geometry do not appear to affect GA convergence. GA is shown to achieve ML-like performance, possibly for lower complexity, i.e., more efficient hardware and power usage.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126739657","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089751
Masafumi Hashimoto, G. Hasegawa, M. Murata
A common strategy for energy saving for wireless network devices is to stay in sleep mode for as long as possible when no data is being transmitted or received. The timings of packet transmission and reception are not determined only by the behavior at the physical and the data link layers; they strongly depend on the behavior of the transport-layer protocols used by upper-layer applications. For effective energy saving, therefore, it is important to understand the relationships between the behavior of the transport-layer protocols and energy efficiency. One effective method for lengthening the idle interval is by transmitting and receiving multiple packets in groups, which is called burst transmission. In this paper, we analyze the energy consumption of TCP data transfer with burst transmission over a wireless LAN. By comparing the energy consumption with and without burst transmission, we show that burst transmission can reduce the energy consumption in TCP data transfer by approximately 60 %. We also discuss which part of wireless LAN devices should be improved for effective energy saving.
{"title":"Energy efficiency analysis of TCP with burst transmission over a wireless LAN","authors":"Masafumi Hashimoto, G. Hasegawa, M. Murata","doi":"10.1109/ISCIT.2011.6089751","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089751","url":null,"abstract":"A common strategy for energy saving for wireless network devices is to stay in sleep mode for as long as possible when no data is being transmitted or received. The timings of packet transmission and reception are not determined only by the behavior at the physical and the data link layers; they strongly depend on the behavior of the transport-layer protocols used by upper-layer applications. For effective energy saving, therefore, it is important to understand the relationships between the behavior of the transport-layer protocols and energy efficiency. One effective method for lengthening the idle interval is by transmitting and receiving multiple packets in groups, which is called burst transmission. In this paper, we analyze the energy consumption of TCP data transfer with burst transmission over a wireless LAN. By comparing the energy consumption with and without burst transmission, we show that burst transmission can reduce the energy consumption in TCP data transfer by approximately 60 %. We also discuss which part of wireless LAN devices should be improved for effective energy saving.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123366950","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6092150
Yan Wei, Zhifeng Zhao, Honggang Zhang
The information and communication technolo-gies(ICT)industry has emerged as one of the main future consumers of the world energy and the radio access network, specially BS(base station) consumes over 80%. Thus this paper focuses on the BS energy efficiency issues of heterogeneous cellular networks. We analyze the energy saving potential of adaptively turning on and off some BSs to minimize the number of working BSs, based on traffic data prediction through spatio-temporal compressive sensing. Simulation results prove the accuracy of the traffic forecasting and large energy efficiency improvement.
{"title":"Dynamic energy savings in heterogeneous cellular networks based on traffic prediction using compressive sensing","authors":"Yan Wei, Zhifeng Zhao, Honggang Zhang","doi":"10.1109/ISCIT.2011.6092150","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092150","url":null,"abstract":"The information and communication technolo-gies(ICT)industry has emerged as one of the main future consumers of the world energy and the radio access network, specially BS(base station) consumes over 80%. Thus this paper focuses on the BS energy efficiency issues of heterogeneous cellular networks. We analyze the energy saving potential of adaptively turning on and off some BSs to minimize the number of working BSs, based on traffic data prediction through spatio-temporal compressive sensing. Simulation results prove the accuracy of the traffic forecasting and large energy efficiency improvement.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122410547","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089745
Xiaochun Wu, Fengyu Zhang, Chunming Wu, Qiang Yang
Network virtualization, through building multiple virtual networks on top of a shared substrate, provides a potential strategy for addressing the ossification of the Internet and encourages network innovation. Traffic clustering is the base and key technology in network virtu-alization. This paper presents a two-layer traffic clustering algorithm. In the first layer, different types of user traffic are clustered into LDR and HDR according to their time characteristics, in the second layer, a revised K-means algorithm is introduced to further classify the traffic in HDR set, the result is used to match the user specified virtual network construction parameters to traffic clustering parameters which will provide finer bandwidth management capability for SPs. Numerical results obtained from experimental show that the result of clustering is dynamically and universally adaptive to the different types of traffic. The proposed two-layer traffic clustering scheme contributes to the constructing of virtual networks.
{"title":"A two-layer traffic clustering framework for network virtualization","authors":"Xiaochun Wu, Fengyu Zhang, Chunming Wu, Qiang Yang","doi":"10.1109/ISCIT.2011.6089745","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089745","url":null,"abstract":"Network virtualization, through building multiple virtual networks on top of a shared substrate, provides a potential strategy for addressing the ossification of the Internet and encourages network innovation. Traffic clustering is the base and key technology in network virtu-alization. This paper presents a two-layer traffic clustering algorithm. In the first layer, different types of user traffic are clustered into LDR and HDR according to their time characteristics, in the second layer, a revised K-means algorithm is introduced to further classify the traffic in HDR set, the result is used to match the user specified virtual network construction parameters to traffic clustering parameters which will provide finer bandwidth management capability for SPs. Numerical results obtained from experimental show that the result of clustering is dynamically and universally adaptive to the different types of traffic. The proposed two-layer traffic clustering scheme contributes to the constructing of virtual networks.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134246468","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089715
Lie Jiang, Li Yu, Zilong Chen
Inspired by the idea of cross-layer analysis and Network Calculus theory, an analytical model for wireless network, which combines the essential knowledge of both, is proposed in this paper by mapping the characteristic of network layer, link layer and physical layer into concatenation of a sequence of Network Calculus components. In addition, the effect of terminal mobility has been considered in our modeling. The proposed model is applied to derive the service curve of wireless network, which consequently enables the calculation of delay and backlog performances under different terminal moving speeds. Simulation results verify the fact that our model provides an accurate performance analysis of wireless network concerning the impact of terminal mobility.
{"title":"Mobility performance analysis in wireless network based on a cross-layer network calculus model","authors":"Lie Jiang, Li Yu, Zilong Chen","doi":"10.1109/ISCIT.2011.6089715","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089715","url":null,"abstract":"Inspired by the idea of cross-layer analysis and Network Calculus theory, an analytical model for wireless network, which combines the essential knowledge of both, is proposed in this paper by mapping the characteristic of network layer, link layer and physical layer into concatenation of a sequence of Network Calculus components. In addition, the effect of terminal mobility has been considered in our modeling. The proposed model is applied to derive the service curve of wireless network, which consequently enables the calculation of delay and backlog performances under different terminal moving speeds. Simulation results verify the fact that our model provides an accurate performance analysis of wireless network concerning the impact of terminal mobility.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115692185","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089716
Miaomiao Hua, Lida Dong
Wireless Highway Addressable Remote Transducer (HART) uses Time Division Multiple Access (TDMA) and channel hopping to communicate between devices. So it is important to keep high accurate time synchronization for a wireless network. This paper proposes a closed-loop adjusting strategy for time synchronization (CATS) which deals with the dramatic variation of oscillator drift rates. CATS is based on double sampling periods, i.e., a synchronization period and an adjusting period. The variation of relative drift rate between different nodes is estimated in the synchronization period. The closed-loop control law is carried out in the adjusting period, which is derived from the estimator of relative drift rate variation. The experimental results indicate that CATS achieves almost the same accuracy as the flooding time synchronization protocol (FTSP) with the regression table of 8(FTSP-8), and it outperforms FTSP-16. Furthermore, it's revealed that CATS achieves lower computational complexity and stronger environmental adaptation than FTSP does.
{"title":"A closed-loop adjusting strategy for wireless HART time synchronization","authors":"Miaomiao Hua, Lida Dong","doi":"10.1109/ISCIT.2011.6089716","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089716","url":null,"abstract":"Wireless Highway Addressable Remote Transducer (HART) uses Time Division Multiple Access (TDMA) and channel hopping to communicate between devices. So it is important to keep high accurate time synchronization for a wireless network. This paper proposes a closed-loop adjusting strategy for time synchronization (CATS) which deals with the dramatic variation of oscillator drift rates. CATS is based on double sampling periods, i.e., a synchronization period and an adjusting period. The variation of relative drift rate between different nodes is estimated in the synchronization period. The closed-loop control law is carried out in the adjusting period, which is derived from the estimator of relative drift rate variation. The experimental results indicate that CATS achieves almost the same accuracy as the flooding time synchronization protocol (FTSP) with the regression table of 8(FTSP-8), and it outperforms FTSP-16. Furthermore, it's revealed that CATS achieves lower computational complexity and stronger environmental adaptation than FTSP does.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115740325","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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