Pub Date : 1996-10-15DOI: 10.1109/PIMRC.1996.567421
Jee-Wey Wang, J. Wen
A new protocol called non-collision packet reservation multiple access (NC-PRMA) is introduced. Two kinds of duplexing schemes, frequency division duplexing (FDD) and shared time division duplexing (STDD), are taken into account. For the FDD scheme, each speech terminal is modeled as a two-state Markov process, whereas for the STDD scheme, each two-way conversation is characterized by a three-state Markov process. After modeling the offered traffic, the system performance measures, including channel throughput, mean access delay, and packet dropping probability are evaluated. In particular, the system capacities of both schemes are emphasized. The system capacity, denoted by M/sub 0.01/ is defined as the maximum number of conversations which can be supported under the constraint of packet dropping probability being no more than 1%. It is shown that the values of M/sub 0.01/ for the FDD and STDD schemes are about 38 and 45, respectively. This indicates that the STDD scheme achieves a significant improvement in system capacity relative to the FDD scheme. In addition, the numerical and simulation results show that our analytical approach yields reasonable accurate results.
{"title":"Performance comparisons of STDD and FDD schemes for TDMA systems using NC-PRMA protocol","authors":"Jee-Wey Wang, J. Wen","doi":"10.1109/PIMRC.1996.567421","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567421","url":null,"abstract":"A new protocol called non-collision packet reservation multiple access (NC-PRMA) is introduced. Two kinds of duplexing schemes, frequency division duplexing (FDD) and shared time division duplexing (STDD), are taken into account. For the FDD scheme, each speech terminal is modeled as a two-state Markov process, whereas for the STDD scheme, each two-way conversation is characterized by a three-state Markov process. After modeling the offered traffic, the system performance measures, including channel throughput, mean access delay, and packet dropping probability are evaluated. In particular, the system capacities of both schemes are emphasized. The system capacity, denoted by M/sub 0.01/ is defined as the maximum number of conversations which can be supported under the constraint of packet dropping probability being no more than 1%. It is shown that the values of M/sub 0.01/ for the FDD and STDD schemes are about 38 and 45, respectively. This indicates that the STDD scheme achieves a significant improvement in system capacity relative to the FDD scheme. In addition, the numerical and simulation results show that our analytical approach yields reasonable accurate results.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126657339","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.567436
O. Ucan
In this paper, to improve bandwidth efficiency and error performance, partial response signaling (PRS) and trellis coded modulation (TCM) are combined together and named as QPR-TCM. The emphasis in this paper is on the jitter and error performance of QPR-TCM and neural network equivalent models in the fading environment with ideal channel state information (CSI) and no side information exist on the phase noise process. Analytical upper bounds are derived using Chernoff bounding technique, combined with the modified generating functional approach. One interesting result is that the bit error probability upper bounds of the proposed scheme is better than 4QAM-TCM for SNR values greater than a threshold, which have the best error performance till now. Neural network models of QPR-TCM schemes are introduced for the first time in the literature for fading channels and the bit error event curves are derived using the back propagation algorithm. It is shown that neuro-computing results confirm the analytical approach.
{"title":"Jitter and error performance analysis of QPR-TCM and neural network equivalent systems over mobile satellite channels","authors":"O. Ucan","doi":"10.1109/PIMRC.1996.567436","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567436","url":null,"abstract":"In this paper, to improve bandwidth efficiency and error performance, partial response signaling (PRS) and trellis coded modulation (TCM) are combined together and named as QPR-TCM. The emphasis in this paper is on the jitter and error performance of QPR-TCM and neural network equivalent models in the fading environment with ideal channel state information (CSI) and no side information exist on the phase noise process. Analytical upper bounds are derived using Chernoff bounding technique, combined with the modified generating functional approach. One interesting result is that the bit error probability upper bounds of the proposed scheme is better than 4QAM-TCM for SNR values greater than a threshold, which have the best error performance till now. Neural network models of QPR-TCM schemes are introduced for the first time in the literature for fading channels and the bit error event curves are derived using the back propagation algorithm. It is shown that neuro-computing results confirm the analytical approach.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126371974","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.567501
W.C.-Y. Lee
Multi-dimensional mobile communication is a key technology for the future. Multi-dimension stands for a broad category of systems; multi-information media, multi-transmission media, and multi-layered networks. In the future, wireless communications, including mobile communications, will become an on-going, rapidly changing technology. Network providers will develop an ideal broadband multi-dimensional network. The mobile communication system will become a component of the overall network. Service providers will purchase the right of accessing the network, and their business services will no longer have any restrictions. The information providers will also provide subscribers with information through service providers. We are moving into a global information economy.
{"title":"Future vision for wireless communications","authors":"W.C.-Y. Lee","doi":"10.1109/PIMRC.1996.567501","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567501","url":null,"abstract":"Multi-dimensional mobile communication is a key technology for the future. Multi-dimension stands for a broad category of systems; multi-information media, multi-transmission media, and multi-layered networks. In the future, wireless communications, including mobile communications, will become an on-going, rapidly changing technology. Network providers will develop an ideal broadband multi-dimensional network. The mobile communication system will become a component of the overall network. Service providers will purchase the right of accessing the network, and their business services will no longer have any restrictions. The information providers will also provide subscribers with information through service providers. We are moving into a global information economy.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126433222","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.568479
Tan-Hsu Tan, Wen-Whei Chang
Errors encountered in digital mobile radio channels are not independent but exhibit varying degrees of statistical dependencies. In many mobile applications, Gilbert's (1960) finite-state Markov chain model has been shown to adequately characterize the bursty-noise binary channels. An estimation method based on the simulated annealing algorithm is proposed for computing the model. Parameters from the sample error sequences. Experimental results indicate that the simulated annealing method yields more accurate identification at a faster convergence rate for comparison with the gradient iterative method.
{"title":"Estimation of Gilbert's model parameters using the simulated annealing method","authors":"Tan-Hsu Tan, Wen-Whei Chang","doi":"10.1109/PIMRC.1996.568479","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568479","url":null,"abstract":"Errors encountered in digital mobile radio channels are not independent but exhibit varying degrees of statistical dependencies. In many mobile applications, Gilbert's (1960) finite-state Markov chain model has been shown to adequately characterize the bursty-noise binary channels. An estimation method based on the simulated annealing algorithm is proposed for computing the model. Parameters from the sample error sequences. Experimental results indicate that the simulated annealing method yields more accurate identification at a faster convergence rate for comparison with the gradient iterative method.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122320810","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.568393
K. Ban, M. Katayama, T. Yamazato, A. Ogawa
In multipath fading channels, the direct-sequence spread spectrum (DS/SS) technique is often employed because of the capability to resolve signals from different paths and realize path diversity at the receiver. This advantage of DS/SS, however, is only when the time difference of propagation delay between paths is greater than a chip duration. In indoor communications, the delay spread is often very small and the above condition on the delay and chip duration is no longer satisfied, and this performance improvement by the path diversity with conventional DS/SS systems cannot be expected. In this paper we propose a new diversity technique for indoor wireless communication systems where delay spread is smaller than a chip duration. In this system, the transmitter sends signals at the same time from multiple antennas with intentional time delays, which allow a receiver to distinguish and combine the signals from different antennas.
{"title":"The DS/CDMA system using transmission diversity for indoor wireless communications","authors":"K. Ban, M. Katayama, T. Yamazato, A. Ogawa","doi":"10.1109/PIMRC.1996.568393","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568393","url":null,"abstract":"In multipath fading channels, the direct-sequence spread spectrum (DS/SS) technique is often employed because of the capability to resolve signals from different paths and realize path diversity at the receiver. This advantage of DS/SS, however, is only when the time difference of propagation delay between paths is greater than a chip duration. In indoor communications, the delay spread is often very small and the above condition on the delay and chip duration is no longer satisfied, and this performance improvement by the path diversity with conventional DS/SS systems cannot be expected. In this paper we propose a new diversity technique for indoor wireless communication systems where delay spread is smaller than a chip duration. In this system, the transmitter sends signals at the same time from multiple antennas with intentional time delays, which allow a receiver to distinguish and combine the signals from different antennas.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116117106","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.568436
M. Katakura, S. Tanabe, I. Matsumoto, K. Saijo, A. Yoshizawa, Y. Mogi
This paper presents an analog base band processor for dual-mode code division multiple access (CDMA)/FM cellular phone systems. The processor interfaces between the intermediate-section and the digital processing circuitry of the telephone. By employing an unique filter circuitry technology, the precise and stable CDMA/FM filter characteristics in the RX/TX blocks have been realized with a trimming-free procedure. This analog base band processor has been designed and fabricated by using a 0.8 /spl mu/m pure bipolar process named ECLA with npn type transistors performance with f/sub T/ as high as 14 GHz. By such technologies, its power consumption is reduced to as low as 132 mW at the CDMA RX/TX mode.
本文提出了一种用于双模码分多址/调频蜂窝电话系统的模拟基带处理器。处理器是电话中间部分和数字处理电路之间的接口。采用一种独特的滤波电路技术，在RX/TX模块中实现了精确稳定的CDMA/FM滤波特性。该模拟基带处理器采用0.8 /spl μ l /m纯双极工艺ECLA设计制作，具有npn型晶体管性能，f/sub / T/高达14 GHz。通过这些技术，在CDMA RX/TX模式下，其功耗降至132兆瓦。
{"title":"Analog base band processor with trimming-free filters for CDMA/FM cellular phone systems","authors":"M. Katakura, S. Tanabe, I. Matsumoto, K. Saijo, A. Yoshizawa, Y. Mogi","doi":"10.1109/PIMRC.1996.568436","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568436","url":null,"abstract":"This paper presents an analog base band processor for dual-mode code division multiple access (CDMA)/FM cellular phone systems. The processor interfaces between the intermediate-section and the digital processing circuitry of the telephone. By employing an unique filter circuitry technology, the precise and stable CDMA/FM filter characteristics in the RX/TX blocks have been realized with a trimming-free procedure. This analog base band processor has been designed and fabricated by using a 0.8 /spl mu/m pure bipolar process named ECLA with npn type transistors performance with f/sub T/ as high as 14 GHz. By such technologies, its power consumption is reduced to as low as 132 mW at the CDMA RX/TX mode.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116129624","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.568466
Songchar Jiang, L. Lin, W. Weng
This paper proposes a performance evaluation approach for integrated voice and data services on CDMA wireless LANs. For random access schemes, dynamic behavior of a CDMA channel implies that we must be cautious in choosing an evaluation model which has to include the effect of dynamic error rates. The approach shown in this paper is to employ a Poisson error model which takes the occurrence of errors as a Poisson process and the occurring rate is dependent on the channel traffic. Based on this assumption, a continuous-time Markov chain model can be further developed to evaluate the throughput and delay performance. This approach can certainly apply to evaluation of many random access protocols.
{"title":"An evaluation model for integrated services on CDMA wireless LANs","authors":"Songchar Jiang, L. Lin, W. Weng","doi":"10.1109/PIMRC.1996.568466","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568466","url":null,"abstract":"This paper proposes a performance evaluation approach for integrated voice and data services on CDMA wireless LANs. For random access schemes, dynamic behavior of a CDMA channel implies that we must be cautious in choosing an evaluation model which has to include the effect of dynamic error rates. The approach shown in this paper is to employ a Poisson error model which takes the occurrence of errors as a Poisson process and the occurring rate is dependent on the channel traffic. Based on this assumption, a continuous-time Markov chain model can be further developed to evaluate the throughput and delay performance. This approach can certainly apply to evaluation of many random access protocols.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116231620","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.567491
P. Lehne, M. Pettersen
Diversity measurements have been performed in microcellular environments where DECT typically might be implemented. The intention has been to investigate how well different implementations of antenna space diversity can combat the problems DECT experiences in multipath environments. Diversity with 2 antennas and selection/switching based on signal level and on delay spread has been investigated, and the effect on the delay spread statistics has been studied. Measurements have been performed in three different types of scenarios; both radio base station (RBS) and portable part (PP) indoors (indoor case), RBS outdoors and PP indoors (outdoor to indoor case) and both RBS and PP outdoors (outdoor case). For the indoor case the delay spread values were small. The most severe time dispersion was observed in the outdoor to indoor case, where delay spread values exceeded 100 ns in almost 50% of the cases. In the outdoor scenario delay spread values above 100 ns were observed for approximately 10% of the cases. It seemed that for both the outdoor, and outdoor to indoor cases, where the time dispersion may cause problems for DECT performance, the diversity algorithm should be based on some other selection/switching criterion than signal level, preferably BER or some other quality criterion. In the indoor environment, signal level as a selection/switching criterion should be sufficient. The work presented in this paper is part of an investigation of DECT performance in environments which DECT has not been originally designed for, to possibly extend the usage of DECT for RLL applications and as a public access system.
{"title":"Space diversity measurements for DECT in indoor and outdoor microcells","authors":"P. Lehne, M. Pettersen","doi":"10.1109/PIMRC.1996.567491","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567491","url":null,"abstract":"Diversity measurements have been performed in microcellular environments where DECT typically might be implemented. The intention has been to investigate how well different implementations of antenna space diversity can combat the problems DECT experiences in multipath environments. Diversity with 2 antennas and selection/switching based on signal level and on delay spread has been investigated, and the effect on the delay spread statistics has been studied. Measurements have been performed in three different types of scenarios; both radio base station (RBS) and portable part (PP) indoors (indoor case), RBS outdoors and PP indoors (outdoor to indoor case) and both RBS and PP outdoors (outdoor case). For the indoor case the delay spread values were small. The most severe time dispersion was observed in the outdoor to indoor case, where delay spread values exceeded 100 ns in almost 50% of the cases. In the outdoor scenario delay spread values above 100 ns were observed for approximately 10% of the cases. It seemed that for both the outdoor, and outdoor to indoor cases, where the time dispersion may cause problems for DECT performance, the diversity algorithm should be based on some other selection/switching criterion than signal level, preferably BER or some other quality criterion. In the indoor environment, signal level as a selection/switching criterion should be sufficient. The work presented in this paper is part of an investigation of DECT performance in environments which DECT has not been originally designed for, to possibly extend the usage of DECT for RLL applications and as a public access system.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125625321","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.567547
M. Choy, Ambuj K. Singh
The efficiency of channel assignment in a cellular telephone system is considered using the measures of successful channel assignment ratio as well as response time. Existing paradigms of mutual exclusion and dining philosophers from distributed systems are used to synthesize new algorithms that optimize both measures. The results are verified by extensive simulations.
{"title":"Efficient distributed algorithms for dynamic channel assignment","authors":"M. Choy, Ambuj K. Singh","doi":"10.1109/PIMRC.1996.567547","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567547","url":null,"abstract":"The efficiency of channel assignment in a cellular telephone system is considered using the measures of successful channel assignment ratio as well as response time. Existing paradigms of mutual exclusion and dining philosophers from distributed systems are used to synthesize new algorithms that optimize both measures. The results are verified by extensive simulations.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122790192","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 : 1996-10-15DOI: 10.1109/PIMRC.1996.567539
M. Nofal, Yaser Abd-Allah, A. Attia, K. El-Nahla, M. Kamal
A simulation study of a generic broadband integrated network is introduced. The network provides a wide range of services to multiple classes of users with different quality and transmission rate requirements. In order to achieve the performance objectives, a variety of service protocols are used. These include serving all users on a blocked calls cleared basis, modifying the transmission rate according to the available speed, introducing queuing facilities to wideband messages as well as combination of them. Using a computer simulation model, numerical results for the network performance under such protocols are presented and discussed.
{"title":"A simulation study of generic broadband wireless integrated networks","authors":"M. Nofal, Yaser Abd-Allah, A. Attia, K. El-Nahla, M. Kamal","doi":"10.1109/PIMRC.1996.567539","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567539","url":null,"abstract":"A simulation study of a generic broadband integrated network is introduced. The network provides a wide range of services to multiple classes of users with different quality and transmission rate requirements. In order to achieve the performance objectives, a variety of service protocols are used. These include serving all users on a blocked calls cleared basis, modifying the transmission rate according to the available speed, introducing queuing facilities to wideband messages as well as combination of them. Using a computer simulation model, numerical results for the network performance under such protocols are presented and discussed.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"268 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122835597","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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