Pub Date : 1996-10-15DOI: 10.1109/PIMRC.1996.568481
Y. Akaiwa, H. Furukawa, T. Onishi
Channel segregation, a distributed dynamic channel assignment method is applied to small cell systems in order to avoid intermodulation interference (IMI). Computer simulation is made to investigate the channel selection pattern achieved with this scheme for the assumed systems affected by IMI. The obtained channel selection patterns are shown to be free from any possible IMIs caused by the 3rd order products of the selected channels.
{"title":"Application of channel segregation for automatic channel selection free from intermodulation interference","authors":"Y. Akaiwa, H. Furukawa, T. Onishi","doi":"10.1109/PIMRC.1996.568481","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568481","url":null,"abstract":"Channel segregation, a distributed dynamic channel assignment method is applied to small cell systems in order to avoid intermodulation interference (IMI). Computer simulation is made to investigate the channel selection pattern achieved with this scheme for the assumed systems affected by IMI. The obtained channel selection patterns are shown to be free from any possible IMIs caused by the 3rd order products of the selected channels.","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":"129437498","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.1996.567478
C. Apostolas, R. Tafazolli, B. Evans
We describe the main principles governing the ETSI-RES 10 HIPERLAN standard for the deployment of ad-hoc wireless local area networks. Focusing on the requirements for supporting delay sensitive services, we compare the performance of the multiple access method adopted in HIPERLAN (called EY-NPMA), to that of a dynamic TDMA access technique.
{"title":"Comparison between elimination yield non pre-emptive priority multiple access (EY-NPMA) and dynamic TDMA (D-TDMA)","authors":"C. Apostolas, R. Tafazolli, B. Evans","doi":"10.1109/PIMRC.1996.567478","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567478","url":null,"abstract":"We describe the main principles governing the ETSI-RES 10 HIPERLAN standard for the deployment of ad-hoc wireless local area networks. Focusing on the requirements for supporting delay sensitive services, we compare the performance of the multiple access method adopted in HIPERLAN (called EY-NPMA), to that of a dynamic TDMA access technique.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"14 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":"129140472","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.1996.567531
J. Wey, Wei-Pang Yang, Yi-Bing Lin
The signaling traffic between access managers (AMs) and home location register (HLR) are SS7 signaling messages in the personal access communication system (PACS) system. These signaling messages are for the transportation of subscriber unit (SU) registration, call origination, and call delivery, and also for authentication in these procedures. The signaling traffic is referred to mobility management traffic. In addition, the performance of mobility management traffic plays an essential role in the performance of the whole PACS system network. In this paper, we propose an M/G/1 traffic analysis on the PACS mobility traffic between AMs and HLR by using the mobile, business, and residential subscriber profiles. In addition, four performance metrics are investigated to observe the mobility characteristics with various subscriber profiles, which include waiting times at the AM and HLR average query response times, average update response times, and the expected numbers of messages per second exchanged between the AM and HLR. Finally, some observations and comments are made for the PACS system.
在PACS (personal access communication system)系统中，AMs (access manager)和HLR (home location register)之间的信令流量是SS7信令消息。这些信令消息用于传输用户单元(SU)注册、呼叫发起和呼叫传递，也用于这些过程中的身份验证。信令业务称为移动性管理业务。此外，移动管理业务的性能对整个PACS系统网络的性能起着至关重要的作用。在本文中，我们提出了一种基于移动、商业和住宅用户配置文件的AMs和HLR之间的PACS移动流量的M/G/1流量分析方法。此外，还研究了四个性能指标，以观察不同订阅者配置文件的移动性特征，其中包括AM和HLR的等待时间、平均查询响应时间、平均更新响应时间以及AM和HLR之间每秒交换的预期消息数。最后，对PACS系统提出了一些看法和评价。
{"title":"Mobility traffic analysis for PACS using various subscriber profiles","authors":"J. Wey, Wei-Pang Yang, Yi-Bing Lin","doi":"10.1109/PIMRC.1996.567531","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567531","url":null,"abstract":"The signaling traffic between access managers (AMs) and home location register (HLR) are SS7 signaling messages in the personal access communication system (PACS) system. These signaling messages are for the transportation of subscriber unit (SU) registration, call origination, and call delivery, and also for authentication in these procedures. The signaling traffic is referred to mobility management traffic. In addition, the performance of mobility management traffic plays an essential role in the performance of the whole PACS system network. In this paper, we propose an M/G/1 traffic analysis on the PACS mobility traffic between AMs and HLR by using the mobile, business, and residential subscriber profiles. In addition, four performance metrics are investigated to observe the mobility characteristics with various subscriber profiles, which include waiting times at the AM and HLR average query response times, average update response times, and the expected numbers of messages per second exchanged between the AM and HLR. Finally, some observations and comments are made for the PACS system.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"82 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":"123953922","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.1996.568452
A. Pouttu, M. Juntti
The performance of three sub-optimal soft decision metrics with slow frequency hopping non-coherent M-ary FSK is compared. The channel is considered as an AWGN channel with partial band interference. The coding scheme chosen for the comparison is binary convolutional (7,1/3) code. Normalized energy metrics provide good performance in noise interference channels. Clamped average energy metrics give good performance in partial band tone interference thus suggesting good performance in overlay systems.
{"title":"Performance simulations of coded slow frequency hopping M-ary FSK with sub-optimal soft decision metrics in partial band interference","authors":"A. Pouttu, M. Juntti","doi":"10.1109/PIMRC.1996.568452","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568452","url":null,"abstract":"The performance of three sub-optimal soft decision metrics with slow frequency hopping non-coherent M-ary FSK is compared. The channel is considered as an AWGN channel with partial band interference. The coding scheme chosen for the comparison is binary convolutional (7,1/3) code. Normalized energy metrics provide good performance in noise interference channels. Clamped average energy metrics give good performance in partial band tone interference thus suggesting good performance in overlay systems.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"57 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":"123366552","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.1996.567509
I. Bar-David, R. Krishnamoorthy
The design and performance of indoor communication systems are strongly dependent on the delay spread in the impulse response of the channel. The delay spread is due to the abundance of the multipath reflections in the indoor environment. Judicious system design can derive benefit from the availability of the multipath signal to improve the system performance. Such potential improvement is due mainly to the fact that the various multipath components are very weakly dependent on each other, while fading, and a natural temporal diversity situation occurs. For system performance evaluation it is desirable to have an estimate of how the delay spread varies while the received power decreases with increasing transmitter-receiver distance. The simplest possible model that retains the essentials of a dense multipath environment is proposed and analyzed. It assumes that the direct path is blocked and that only scattered signals are received. A small ellipse of focal distance r/sub min/ about the transmitter and receiver is assumed to be free of scatterers. The scatterers are assumed to be Lambertian uncorrelated point-scatterers, uniformly distributed in 2-dimensional space. Secondary reflections are neglected and primary reflections are assumed not to be hampered by the presence of the other point scatterers. This is basically the wide sense stationary uncorrelated scatterers (WSSUS) model often used in communications analysis.
{"title":"Delay spread profiles and receiver performance in a dense multipath environment","authors":"I. Bar-David, R. Krishnamoorthy","doi":"10.1109/PIMRC.1996.567509","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567509","url":null,"abstract":"The design and performance of indoor communication systems are strongly dependent on the delay spread in the impulse response of the channel. The delay spread is due to the abundance of the multipath reflections in the indoor environment. Judicious system design can derive benefit from the availability of the multipath signal to improve the system performance. Such potential improvement is due mainly to the fact that the various multipath components are very weakly dependent on each other, while fading, and a natural temporal diversity situation occurs. For system performance evaluation it is desirable to have an estimate of how the delay spread varies while the received power decreases with increasing transmitter-receiver distance. The simplest possible model that retains the essentials of a dense multipath environment is proposed and analyzed. It assumes that the direct path is blocked and that only scattered signals are received. A small ellipse of focal distance r/sub min/ about the transmitter and receiver is assumed to be free of scatterers. The scatterers are assumed to be Lambertian uncorrelated point-scatterers, uniformly distributed in 2-dimensional space. Secondary reflections are neglected and primary reflections are assumed not to be hampered by the presence of the other point scatterers. This is basically the wide sense stationary uncorrelated scatterers (WSSUS) model often used in communications analysis.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"16 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":"121675780","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.1996.568459
J. S. Lee, L. Miller
The reliability of a CDMA cellular system reverse link is formulated as the probability that the link SNR is above the required threshold, accounting for multiple users, multipath receptions, signal and multipath fading, and Rake multipath diversity processing. Calculations of reliability show the gains obtained through RAKE processing, and the necessity of this processing when multipaths exist. It is shown that when multipath interference and link reliability requirements are accounted for, the number of CDMA users can be much smaller than that predicted using median SNR values.
{"title":"The effect of path diversity (RAKE) on link reliability in CDMA cellular systems-a realistic assessment of system capacity","authors":"J. S. Lee, L. Miller","doi":"10.1109/PIMRC.1996.568459","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568459","url":null,"abstract":"The reliability of a CDMA cellular system reverse link is formulated as the probability that the link SNR is above the required threshold, accounting for multiple users, multipath receptions, signal and multipath fading, and Rake multipath diversity processing. Calculations of reliability show the gains obtained through RAKE processing, and the necessity of this processing when multipaths exist. It is shown that when multipath interference and link reliability requirements are accounted for, the number of CDMA users can be much smaller than that predicted using median SNR values.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"59 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":"127695617","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.1996.568469
A. Iera, S. Marano, A. Molinaro
Wireless-PCS systems, through the introduction of new conception control functions, aim to respond to the user expectation of high performing services and the need for flexibility in the management of disparate categories of multimedia and multi-requirement applications supported by the networks. This paper contributes to the ongoing research work in this scenario by describing some proposals for the handling of multimedia teleservices both at the transport and control level, across the wired and wireless sides of an ATM-based wireless PCS system. Admission control on both sides, mobility management in the fixed side and resource allocation renegotiation are topics on which the study focuses.
{"title":"On the management of end-to-end multimedia and multibearer connections in a personal communications system","authors":"A. Iera, S. Marano, A. Molinaro","doi":"10.1109/PIMRC.1996.568469","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568469","url":null,"abstract":"Wireless-PCS systems, through the introduction of new conception control functions, aim to respond to the user expectation of high performing services and the need for flexibility in the management of disparate categories of multimedia and multi-requirement applications supported by the networks. This paper contributes to the ongoing research work in this scenario by describing some proposals for the handling of multimedia teleservices both at the transport and control level, across the wired and wireless sides of an ATM-based wireless PCS system. Admission control on both sides, mobility management in the fixed side and resource allocation renegotiation are topics on which the study focuses.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"77 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":"125743736","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.1996.567519
J. Wigard, P. Mogensen
To evaluate the performance of a mobile radio system, both network and link quality aspects have to be evaluated. A network simulator is often used to find the influence of different system parameters, such as DTX, frequency hopping and power control. To complete the evaluation, a link simulator has to be integrated in the network simulator, so that each radio link can be simulated. An obvious method to integrate the radio link quality aspects with the network simulator is to use the output of the network part of the simulator as input for an integrated link simulator. This will however lead to time consuming simulations, In this paper a simpler method is presented, which leads to a shorter simulation time. The output of the network part of the simulator, expressed in signal to interference (C/I) values, is used as input for look-up tables, which lead to a BER and a frame erasure rate (FER) for each radio link. These look-up tables are depending on the hopping pattern and channel profile and they are also receiver dependent. The results of the mapping method are good, except for a few situations, where the prediction of the BER goes wrong. This happens when sequential hopping with a few frequencies is used and the speed of the mobile user is low. In general the presented predictions are within 1 dB (FER) and within 0.2 dB (BER).
{"title":"A simple mapping from C/I to FER and BER for a GSM type of air-interface","authors":"J. Wigard, P. Mogensen","doi":"10.1109/PIMRC.1996.567519","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567519","url":null,"abstract":"To evaluate the performance of a mobile radio system, both network and link quality aspects have to be evaluated. A network simulator is often used to find the influence of different system parameters, such as DTX, frequency hopping and power control. To complete the evaluation, a link simulator has to be integrated in the network simulator, so that each radio link can be simulated. An obvious method to integrate the radio link quality aspects with the network simulator is to use the output of the network part of the simulator as input for an integrated link simulator. This will however lead to time consuming simulations, In this paper a simpler method is presented, which leads to a shorter simulation time. The output of the network part of the simulator, expressed in signal to interference (C/I) values, is used as input for look-up tables, which lead to a BER and a frame erasure rate (FER) for each radio link. These look-up tables are depending on the hopping pattern and channel profile and they are also receiver dependent. The results of the mapping method are good, except for a few situations, where the prediction of the BER goes wrong. This happens when sequential hopping with a few frequencies is used and the speed of the mobile user is low. In general the presented predictions are within 1 dB (FER) and within 0.2 dB (BER).","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"1 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":"131359812","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.1996.568453
F. M. Assis, M. Alencar
This paper presents a comparison of performance for FH-CDMA systems using either algebraic geometric (AG) or Reed-Solomon (RS) codes, for error correction. The performance measures of interest are the achievable region and the channel throughput. The achievable rate region is defined as the set of all pairs of code rate and number of users for which communication is possible, with error probability below a fixed value. The throughput measures the expected number of successful codeword transmissions per unit bandwidth.
{"title":"Comparing algebraic geometric and Reed-Solomon codes for FH-CDMA applications","authors":"F. M. Assis, M. Alencar","doi":"10.1109/PIMRC.1996.568453","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.568453","url":null,"abstract":"This paper presents a comparison of performance for FH-CDMA systems using either algebraic geometric (AG) or Reed-Solomon (RS) codes, for error correction. The performance measures of interest are the achievable region and the channel throughput. The achievable rate region is defined as the set of all pairs of code rate and number of users for which communication is possible, with error probability below a fixed value. The throughput measures the expected number of successful codeword transmissions per unit bandwidth.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"18 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":"132220062","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.1996.567464
R. Jain, S. Rajagopalan, L. Chang
Current cellular subscribers have a geographic phone number (e.g. in AMPS and US digital cellular systems) or a number which contains the network provider's identity (e.g. in GSM), and whenever subscribers register or receive (and possibly, originate) a call, a home location register (HLR) database has to be queried. A special feature of next generation wireless access service will be to support PCS and wireless subscribers with portable personal numbers, or non-geographic phone numbers (NGPN), that do not indicate the service provider or HLR database serving the user. In addition the global title translation (GTT) function that converts the subscriber's number to an HLR database address may not be available when the wired backbone is an ATM network. Thus a key function required will be to translate an NGPN to the ID of the HLR which serves the subscriber, a process we call NGPN translation. (Note that the same functionality is also needed for subscribers with local, portable phone numbers.) We discuss the requirements of NGPN translation and some alternative schemes. We propose a scheme for fast, efficient, scalable and flexible NGPN translation which applies ideas of dynamic hashing, caching, and indirection. The scheme uses a hash function in the visiting location registers (VLR) (or serving SCP) and a set of distributed translation servers which store the NGPN-to-HLR mapping.
{"title":"A hashing scheme for phone number portability in PCS systems with ATM backbones","authors":"R. Jain, S. Rajagopalan, L. Chang","doi":"10.1109/PIMRC.1996.567464","DOIUrl":"https://doi.org/10.1109/PIMRC.1996.567464","url":null,"abstract":"Current cellular subscribers have a geographic phone number (e.g. in AMPS and US digital cellular systems) or a number which contains the network provider's identity (e.g. in GSM), and whenever subscribers register or receive (and possibly, originate) a call, a home location register (HLR) database has to be queried. A special feature of next generation wireless access service will be to support PCS and wireless subscribers with portable personal numbers, or non-geographic phone numbers (NGPN), that do not indicate the service provider or HLR database serving the user. In addition the global title translation (GTT) function that converts the subscriber's number to an HLR database address may not be available when the wired backbone is an ATM network. Thus a key function required will be to translate an NGPN to the ID of the HLR which serves the subscriber, a process we call NGPN translation. (Note that the same functionality is also needed for subscribers with local, portable phone numbers.) We discuss the requirements of NGPN translation and some alternative schemes. We propose a scheme for fast, efficient, scalable and flexible NGPN translation which applies ideas of dynamic hashing, caching, and indirection. The scheme uses a hash function in the visiting location registers (VLR) (or serving SCP) and a set of distributed translation servers which store the NGPN-to-HLR mapping.","PeriodicalId":206655,"journal":{"name":"Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications","volume":"66 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":"130066378","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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