Pub Date : 2006-07-31DOI: 10.1109/ISCN.2006.1662501
M. Settembre, M. Puleri, S. Garritano, P. Testa, R. Albanese, M. Mancini, V. L. Curto
The challenge for broadband fixed wireless access (BFWA) systems, which represent an attractive solution for broadband access in the last mile and for wireless backhauling applications in the "middle mile", lies in providing high data rates and quality of service (QoS). Such requirements mainly derive from the need to provide new bandwidth consuming multimedia services and applications, efficient handling of IP traffic, effective use of the limited radio spectrum and a greater backhaul capacity to support the increased number of users per cell site. IEEE 802.16 family of standards and its associated consortium WiMAX are gaining more and more interest in the telecommunication areas as broadband fixed wireless access solution with possible extension in nomadic and mobile area. Its main leverages are an efficient handling of IP traffic, the support of channel adaptivity and advanced QoS management. This paper aims at defining a new packet-based scheduling strategy for an IEEE 802.16 system supporting variable length MAC protocol data units (PDUs) and adaptive coding and modulation while fulfilling QoS requirements. A performance analysis of the proposed scheduler is presented and discussed in terms of packet transfer delay, MAC overhead and average throughput
{"title":"Performance analysis of an efficient packet-based IEEE 802.16 MAC supporting adaptive modulation and coding","authors":"M. Settembre, M. Puleri, S. Garritano, P. Testa, R. Albanese, M. Mancini, V. L. Curto","doi":"10.1109/ISCN.2006.1662501","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662501","url":null,"abstract":"The challenge for broadband fixed wireless access (BFWA) systems, which represent an attractive solution for broadband access in the last mile and for wireless backhauling applications in the \"middle mile\", lies in providing high data rates and quality of service (QoS). Such requirements mainly derive from the need to provide new bandwidth consuming multimedia services and applications, efficient handling of IP traffic, effective use of the limited radio spectrum and a greater backhaul capacity to support the increased number of users per cell site. IEEE 802.16 family of standards and its associated consortium WiMAX are gaining more and more interest in the telecommunication areas as broadband fixed wireless access solution with possible extension in nomadic and mobile area. Its main leverages are an efficient handling of IP traffic, the support of channel adaptivity and advanced QoS management. This paper aims at defining a new packet-based scheduling strategy for an IEEE 802.16 system supporting variable length MAC protocol data units (PDUs) and adaptive coding and modulation while fulfilling QoS requirements. A performance analysis of the proposed scheduler is presented and discussed in terms of packet transfer delay, MAC overhead and average throughput","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"499 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115662843","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662544
Grigorios Plitsis
Chaos engineering for wireless communications is an emerging field of research. There are certain advantages that chaotic dynamics could offer to conventional wireless access systems such as increased security and encryption, low-power communication, and hardware simplicity. This paper describes how chaotic spreading could be used in broadband wireless access systems such as IEEE 802.11b by replacing the spreading sequences with chaotic ones and thus improving the performance under narrowband sinusoidal jammer and Bluetooth interference. The results are being presented with the use of link level simulations. It also describes how quadrature chaos shift keying (QCSK) could be used for wireless sensor networks (WSNs) as the simplicity of hardware when using chaos in communication protocols could successfully lead to cubic millimeter scale sensor nodes and presents the performance of QCSK under narrowband sinusoidal jammer with the use of mathematical models
{"title":"Performance of the application of chaotic signals in IEEE 802.11b and wireless sensor networks","authors":"Grigorios Plitsis","doi":"10.1109/ISCN.2006.1662544","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662544","url":null,"abstract":"Chaos engineering for wireless communications is an emerging field of research. There are certain advantages that chaotic dynamics could offer to conventional wireless access systems such as increased security and encryption, low-power communication, and hardware simplicity. This paper describes how chaotic spreading could be used in broadband wireless access systems such as IEEE 802.11b by replacing the spreading sequences with chaotic ones and thus improving the performance under narrowband sinusoidal jammer and Bluetooth interference. The results are being presented with the use of link level simulations. It also describes how quadrature chaos shift keying (QCSK) could be used for wireless sensor networks (WSNs) as the simplicity of hardware when using chaos in communication protocols could successfully lead to cubic millimeter scale sensor nodes and presents the performance of QCSK under narrowband sinusoidal jammer with the use of mathematical models","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116924213","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662534
R. Dragos, M. Collier
We propose a new family of fair, work conserving traffic scheduling mechanisms that imitate the behavior of the human heart in the cardiovascular system. The algorithms have MAX (where MAX is the maximum packet size) fairness and O(log N) complexity and thus compare favorably with existing algorithms. The algorithms are simple enough to be implemented in hardware
{"title":"Heart-like fair queuing algorithms (HLFQA)","authors":"R. Dragos, M. Collier","doi":"10.1109/ISCN.2006.1662534","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662534","url":null,"abstract":"We propose a new family of fair, work conserving traffic scheduling mechanisms that imitate the behavior of the human heart in the cardiovascular system. The algorithms have MAX (where MAX is the maximum packet size) fairness and O(log N) complexity and thus compare favorably with existing algorithms. The algorithms are simple enough to be implemented in hardware","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122317107","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662520
Gulsum Zeynep Gurkas Aydin, A. Zaim, M. Aydin
Rapidly growing 802.11 wireless local area networks continue to gain popularity in business and computer industry. This growing popularity and usage also caused many improvements on both physical layer and security mechanisms. In this study we investigated the performance of wireless local area networks (WLANs) and security mechanisms available for WLANs. These security mechanisms are wired equivalent privacy (WEP), Wi-Fi protected access (WPA) and 802.11i (WPA2). To examine the impacts of encryption and integrity protection mechanisms provided by WEP, WPA and WPA2, we developed a simulation software. In the first part of our study we tested the performance of IEEE 802.11b, 802.11g and 802.11i networks without security. In the second part we implemented the security mechanisms and investigated the impacts of these security mechanisms on the performance of wireless local area networks
{"title":"Security Mechanisms And Their Performance Impacts On Wireless Local Area Networks","authors":"Gulsum Zeynep Gurkas Aydin, A. Zaim, M. Aydin","doi":"10.1109/ISCN.2006.1662520","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662520","url":null,"abstract":"Rapidly growing 802.11 wireless local area networks continue to gain popularity in business and computer industry. This growing popularity and usage also caused many improvements on both physical layer and security mechanisms. In this study we investigated the performance of wireless local area networks (WLANs) and security mechanisms available for WLANs. These security mechanisms are wired equivalent privacy (WEP), Wi-Fi protected access (WPA) and 802.11i (WPA2). To examine the impacts of encryption and integrity protection mechanisms provided by WEP, WPA and WPA2, we developed a simulation software. In the first part of our study we tested the performance of IEEE 802.11b, 802.11g and 802.11i networks without security. In the second part we implemented the security mechanisms and investigated the impacts of these security mechanisms on the performance of wireless local area networks","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122479450","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662527
N. Rikli, Khaled Al-Omran
A wavelength-routed (WR) optical network using an adaptive burst size (ABS) optical burst switching (OBS) scheme is to be considered. The aim is to improve the offered QoS and offer distinctive class-of-service (CoS) separation for various network conditions in an adaptive way. Specifically, a hybrid triggering policy is suggested to achieve the required network performance, such as average packet loss, average packet delay, and average network utilization, under both light and heavy traffic conditions. Performance results under dynamic and bursty traffic conditions are presented and analyzed
{"title":"Effects of the triggering policy on the performance of an adaptive WR-OBS network with QoS support","authors":"N. Rikli, Khaled Al-Omran","doi":"10.1109/ISCN.2006.1662527","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662527","url":null,"abstract":"A wavelength-routed (WR) optical network using an adaptive burst size (ABS) optical burst switching (OBS) scheme is to be considered. The aim is to improve the offered QoS and offer distinctive class-of-service (CoS) separation for various network conditions in an adaptive way. Specifically, a hybrid triggering policy is suggested to achieve the required network performance, such as average packet loss, average packet delay, and average network utilization, under both light and heavy traffic conditions. Performance results under dynamic and bursty traffic conditions are presented and analyzed","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127032200","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662542
A. Alagoz, Öznur Özkasap, M. Çağlar
We propose an efficient cooperative content distribution protocol in which the cooperation among participants is based on a peer-to-peer (P2P) paradigm. Our main contribution to P2P content distribution is the use of an epidemic communication approach. Since epidemic algorithms are easy to use, robust and adaptive to dynamic conditions, they have found several application areas in distributed systems such as failure detection, data aggregation and database replication. However, they have not been used in cooperative content distribution before. In addition to the use of epidemic algorithms for state exchange among peers, we propose some methods in order to increase utilization of system resources during distribution of the files. We demonstrate effectiveness and scalability of the protocol through our simulation model
{"title":"SeCond: a system for epidemic peer-to-peer content distribution","authors":"A. Alagoz, Öznur Özkasap, M. Çağlar","doi":"10.1109/ISCN.2006.1662542","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662542","url":null,"abstract":"We propose an efficient cooperative content distribution protocol in which the cooperation among participants is based on a peer-to-peer (P2P) paradigm. Our main contribution to P2P content distribution is the use of an epidemic communication approach. Since epidemic algorithms are easy to use, robust and adaptive to dynamic conditions, they have found several application areas in distributed systems such as failure detection, data aggregation and database replication. However, they have not been used in cooperative content distribution before. In addition to the use of epidemic algorithms for state exchange among peers, we propose some methods in order to increase utilization of system resources during distribution of the files. We demonstrate effectiveness and scalability of the protocol through our simulation model","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115781219","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662535
A. Shiibashi, Takeyuki Yajima, Xiaodong Lu, K. Mori
Both high performance and high reliability are necessary for the automatic fare collection system. The IC card ticket system, developed in order to improve the passengers' satisfaction and to reduce the maintenance costs, cannot avoid the requirements, either. However, this new system has a problem; high performance on wireless communications lowers reliability. The solutions are the "autonomous decentralized architecture," the "autonomous decentralized algorithm," and the "autonomous decentralized data consistency technology." This paper introduces the "autonomous decentralized data consistency technology" for high reliability and evaluates the effectiveness by the functional reliability, which depends on how many times this technology runs and how many data the IC card contains. The results show the decentralized processes competitive to the centralized processes under the particular conditions. These conditions are made use of the practical "Suica" system at East Japan Railway Company and the system is running satisfactorily, without any fatal errors
{"title":"The evaluation of high reliability in an autonomous decentralized IC card ticket system","authors":"A. Shiibashi, Takeyuki Yajima, Xiaodong Lu, K. Mori","doi":"10.1109/ISCN.2006.1662535","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662535","url":null,"abstract":"Both high performance and high reliability are necessary for the automatic fare collection system. The IC card ticket system, developed in order to improve the passengers' satisfaction and to reduce the maintenance costs, cannot avoid the requirements, either. However, this new system has a problem; high performance on wireless communications lowers reliability. The solutions are the \"autonomous decentralized architecture,\" the \"autonomous decentralized algorithm,\" and the \"autonomous decentralized data consistency technology.\" This paper introduces the \"autonomous decentralized data consistency technology\" for high reliability and evaluates the effectiveness by the functional reliability, which depends on how many times this technology runs and how many data the IC card contains. The results show the decentralized processes competitive to the centralized processes under the particular conditions. These conditions are made use of the practical \"Suica\" system at East Japan Railway Company and the system is running satisfactorily, without any fatal errors","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133248747","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662523
Dilek Demirel Isci, Fatih Alagöz, M. Çaglayan
Acknowledgment based transport protocols such as TCP have low performance in satellite links, which are characterized by high latencies and high bit error rates. Low performance of TCP in satellite links is due to the fact that TCP packet losses are assumed to be the cause of congestion in the network, which turns out to be an invalid assumption for satellite links. TCP performance enhancing proxies (PEPs) are widely used to overcome the limitations of TCP over satellite links. However, when end-to-end security mechanisms, such as IPSEC, are used, TCP PEP mechanisms can not be used. IPSEC encrypts and/or authenticates the packet header fields that the PEP needs to read or modify. We propose a novel mechanism to integrate IPSEC with TCP PEPs. In our approach, a cryptographic hash of flow identification information is generated and stored in the IP header. The TCP sequence number is also stored in the IP header. Using the hash value and sequence numbers, the PEP is able to match packets and corresponding acknowledgements to regulate the flow. This approach is applicable to PEP mechanisms that need read access to the IP and TCP headers
{"title":"IPSEC over satellite links: a new flow identification method","authors":"Dilek Demirel Isci, Fatih Alagöz, M. Çaglayan","doi":"10.1109/ISCN.2006.1662523","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662523","url":null,"abstract":"Acknowledgment based transport protocols such as TCP have low performance in satellite links, which are characterized by high latencies and high bit error rates. Low performance of TCP in satellite links is due to the fact that TCP packet losses are assumed to be the cause of congestion in the network, which turns out to be an invalid assumption for satellite links. TCP performance enhancing proxies (PEPs) are widely used to overcome the limitations of TCP over satellite links. However, when end-to-end security mechanisms, such as IPSEC, are used, TCP PEP mechanisms can not be used. IPSEC encrypts and/or authenticates the packet header fields that the PEP needs to read or modify. We propose a novel mechanism to integrate IPSEC with TCP PEPs. In our approach, a cryptographic hash of flow identification information is generated and stored in the IP header. The TCP sequence number is also stored in the IP header. Using the hash value and sequence numbers, the PEP is able to match packets and corresponding acknowledgements to regulate the flow. This approach is applicable to PEP mechanisms that need read access to the IP and TCP headers","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133770668","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662545
U. Demir, Özlem Aktaş
Network conditions generally cause errors on network packets. Correction of these errors is in the subject of "forward error correction." Forward error correction is divided into two categories: bit-level forward error correction and packet-level forward error correction. These two categories are unfamiliar. The aim of this study is to make a literature comparison of two alternative packet-level forward error correction codes: Raptor and Reed Solomon. Nowadays when packet-level error correction codes are mentioned, these two techniques are remembered. Reed Solomon FEC codes are found on the Internet and are tested with different network conditions. Raptor codes are commercial and not used broadly yet. But several new technologies (MBMS, DVB and etc.) uses Raptor. This study shows the cases, where Raptor and Reed Solomon are appropriate to use
{"title":"Raptor versus Reed Solomon forward error correction codes","authors":"U. Demir, Özlem Aktaş","doi":"10.1109/ISCN.2006.1662545","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662545","url":null,"abstract":"Network conditions generally cause errors on network packets. Correction of these errors is in the subject of \"forward error correction.\" Forward error correction is divided into two categories: bit-level forward error correction and packet-level forward error correction. These two categories are unfamiliar. The aim of this study is to make a literature comparison of two alternative packet-level forward error correction codes: Raptor and Reed Solomon. Nowadays when packet-level error correction codes are mentioned, these two techniques are remembered. Reed Solomon FEC codes are found on the Internet and are tested with different network conditions. Raptor codes are commercial and not used broadly yet. But several new technologies (MBMS, DVB and etc.) uses Raptor. This study shows the cases, where Raptor and Reed Solomon are appropriate to use","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128388861","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 : 2006-07-31DOI: 10.1109/ISCN.2006.1662517
I. Candan, M. Salamah
In this paper, a time-threshold based multi-guard bandwidth allocation scheme for voice calls is presented. The main idea of the new scheme is based on monitoring the elapsed real time of handoff calls and according to a time threshold (te), a handoff call is either slightly-prioritized or fully-prioritised. A slightly-prioritized handoff call has higher priority than a new call and lower priority than a fully-prioritized handoff call. Also in this paper, the performances of different bandwidth allocation schemes are measured using a crucial general performance metric Z. Z, which is a performance/cost ratio, is a function of the new call blocking probability, handoff call dropping probability and system utilization all together. The results indicate that our scheme outperforms other traditional schemes in terms of performance/cost ratio, and maintains its superiority under different network circumstances
{"title":"A time-threshold based multi-guard bandwidth allocation scheme for cellular networks","authors":"I. Candan, M. Salamah","doi":"10.1109/ISCN.2006.1662517","DOIUrl":"https://doi.org/10.1109/ISCN.2006.1662517","url":null,"abstract":"In this paper, a time-threshold based multi-guard bandwidth allocation scheme for voice calls is presented. The main idea of the new scheme is based on monitoring the elapsed real time of handoff calls and according to a time threshold (te), a handoff call is either slightly-prioritized or fully-prioritised. A slightly-prioritized handoff call has higher priority than a new call and lower priority than a fully-prioritized handoff call. Also in this paper, the performances of different bandwidth allocation schemes are measured using a crucial general performance metric Z. Z, which is a performance/cost ratio, is a function of the new call blocking probability, handoff call dropping probability and system utilization all together. The results indicate that our scheme outperforms other traditional schemes in terms of performance/cost ratio, and maintains its superiority under different network circumstances","PeriodicalId":304528,"journal":{"name":"2006 International Symposium on Computer Networks","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126557681","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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