Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021735
R. Chang, King P. Fung
Firewall support for UDP traffic today is still insecure and inadequate. We propose in this paper a transport layer proxy (TLP) to provide a secure UDP firewall traversal service on the transport layer (the TLP supports TCP as well). For each UDP association with endpoints separated by a TLP server, the TLP server performs user-level or host-level authentication, packet filtering, packet relaying, optional network address translation, session logging, timing-out of idle association, and other security-related functions. The core of the TLP is a two-step TLP binding procedure that makes a UDP association stateful between a TLP client and a TLP server. This binding procedure supports Active UDP Open, Passive UDP Open, and Source-Specific UDP Open, which a local program may perform on a UDP socket.
{"title":"Transport layer proxy for stateful UDP packet filtering","authors":"R. Chang, King P. Fung","doi":"10.1109/ISCC.2002.1021735","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021735","url":null,"abstract":"Firewall support for UDP traffic today is still insecure and inadequate. We propose in this paper a transport layer proxy (TLP) to provide a secure UDP firewall traversal service on the transport layer (the TLP supports TCP as well). For each UDP association with endpoints separated by a TLP server, the TLP server performs user-level or host-level authentication, packet filtering, packet relaying, optional network address translation, session logging, timing-out of idle association, and other security-related functions. The core of the TLP is a two-step TLP binding procedure that makes a UDP association stateful between a TLP client and a TLP server. This binding procedure supports Active UDP Open, Passive UDP Open, and Source-Specific UDP Open, which a local program may perform on a UDP socket.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116878462","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021772
L. Grieco, S. Mascolo, R. Ferorelli
Due to the fundamental end-to-end design principle of the TCP/IP for which the network cannot supply any explicit feedback, today the TCP congestion control algorithm implements an additive increase multiplicative decrease (AIMD) algorithm. It is widely recognized that the AIMD mechanism is at the core of the stability of end-to-end congestion control. In this paper we describe a new mechanism we call additive increase adaptive decrease (AIAD). The key concept of the adaptive decrease mechanism is to adapt congestion window reductions to the bandwidth available at the time the congestion is experienced. We propose Westwood++ TCP as an implementation of the AIAD paradigm, and we consider Reno TCP as an example of the AIMD mechanism for comparison. We derive a mathematical model of the throughput of the AIAD mechanism that shows that Westwood++ is stable, is friendly to Reno and increases the fairness in bandwidth utilization. To confirm the validity of the theoretical model Internet measurements are reported.
{"title":"Additive increase adaptive decrease congestion control: a mathematical model and its experimental validation","authors":"L. Grieco, S. Mascolo, R. Ferorelli","doi":"10.1109/ISCC.2002.1021772","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021772","url":null,"abstract":"Due to the fundamental end-to-end design principle of the TCP/IP for which the network cannot supply any explicit feedback, today the TCP congestion control algorithm implements an additive increase multiplicative decrease (AIMD) algorithm. It is widely recognized that the AIMD mechanism is at the core of the stability of end-to-end congestion control. In this paper we describe a new mechanism we call additive increase adaptive decrease (AIAD). The key concept of the adaptive decrease mechanism is to adapt congestion window reductions to the bandwidth available at the time the congestion is experienced. We propose Westwood++ TCP as an implementation of the AIAD paradigm, and we consider Reno TCP as an example of the AIMD mechanism for comparison. We derive a mathematical model of the throughput of the AIAD mechanism that shows that Westwood++ is stable, is friendly to Reno and increases the fairness in bandwidth utilization. To confirm the validity of the theoretical model Internet measurements are reported.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128255645","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021718
A. Puliafito, O. Tomarchio
Since its appearance, mobile agent technology has been considered as a new and flexible paradigm for distributed application development. However because of code mobility, this paradigm produces new threats to security too, which are of central importance when proposing this technology for commercial applications. We show the security services which have been specifically designed and developed for the MAP agent system. Early performance measurements show how the overhead needed by the security mechanisms introduced can be acceptable if compared with the functionalities provided.
{"title":"Design and development of a practical security model for a mobile agent system","authors":"A. Puliafito, O. Tomarchio","doi":"10.1109/ISCC.2002.1021718","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021718","url":null,"abstract":"Since its appearance, mobile agent technology has been considered as a new and flexible paradigm for distributed application development. However because of code mobility, this paradigm produces new threats to security too, which are of central importance when proposing this technology for commercial applications. We show the security services which have been specifically designed and developed for the MAP agent system. Early performance measurements show how the overhead needed by the security mechanisms introduced can be acceptable if compared with the functionalities provided.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129237283","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021679
D. Dolev, O. Mokryn, Y. Shavitt, Innocenty Sukhov
The competition on clients attention requires sites to update their content frequently. As a result, a large percentage of Web pages are semi-dynamic, i.e., change quite often and stay static between changes. The cost of maintaining consistency for such pages discourages caching solutions. We suggest here an integrated architecture for the scalable delivery of frequently changing hot pages. Our scheme enables sites to dynamically select whether to cyclically multicast a hot page or to unicast it, and to switch between multicast and unicast mechanisms in a transparent way. Our scheme defines a new protocol, called h.t.t.p.m. In addition, it uses currently deployed protocols, and dynamically directs browsers seeking for a URL to multicast channels, while using existing DNS mechanisms. Thus, we enable sites to deliver content to a growing number of users at less cost and during denial of service attacks, while reducing load on core links. We report simulation results that demonstrate the advantages of the integrated architecture, and its significant impact on server and network load, as well as clients delay.
{"title":"An integrated architecture for the scalable delivery of semi-dynamic Web content","authors":"D. Dolev, O. Mokryn, Y. Shavitt, Innocenty Sukhov","doi":"10.1109/ISCC.2002.1021679","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021679","url":null,"abstract":"The competition on clients attention requires sites to update their content frequently. As a result, a large percentage of Web pages are semi-dynamic, i.e., change quite often and stay static between changes. The cost of maintaining consistency for such pages discourages caching solutions. We suggest here an integrated architecture for the scalable delivery of frequently changing hot pages. Our scheme enables sites to dynamically select whether to cyclically multicast a hot page or to unicast it, and to switch between multicast and unicast mechanisms in a transparent way. Our scheme defines a new protocol, called h.t.t.p.m. In addition, it uses currently deployed protocols, and dynamically directs browsers seeking for a URL to multicast channels, while using existing DNS mechanisms. Thus, we enable sites to deliver content to a growing number of users at less cost and during denial of service attacks, while reducing load on core links. We report simulation results that demonstrate the advantages of the integrated architecture, and its significant impact on server and network load, as well as clients delay.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114067089","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021767
S. Garg, Martin Kappes, M. Mani
In this paper we describe the "wireless access server (WAS)". WAS is targeted towards providing QoS and access control features for wireless LAN, specifically 802.11 networks. It is well known that these aspects have significant deficiencies in the widely deployed 802.11 networks. Our work is complementary to the proposed drafts by IEEE's 802.11e and 802.11i Working Groups, which also aim to alleviate some of the limitations in QoS and security. We describe the architecture and components of the server and outline the QoS and access control functionality it provides.
{"title":"Wireless access server for quality of service and location based access control in 802.11 networks","authors":"S. Garg, Martin Kappes, M. Mani","doi":"10.1109/ISCC.2002.1021767","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021767","url":null,"abstract":"In this paper we describe the \"wireless access server (WAS)\". WAS is targeted towards providing QoS and access control features for wireless LAN, specifically 802.11 networks. It is well known that these aspects have significant deficiencies in the widely deployed 802.11 networks. Our work is complementary to the proposed drafts by IEEE's 802.11e and 802.11i Working Groups, which also aim to alleviate some of the limitations in QoS and security. We describe the architecture and components of the server and outline the QoS and access control functionality it provides.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114320503","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021752
D. Hsu
A fiber-optical code-division multiple-access (FO-CDMA) scheme, which is based on spectral coding, is proposed. The spectral coding is based on the pseudo-orthogonality of FO-CDMA codes properly written in the fiber Bragg grating (FBG) devices. A pair of maximal-length sequence codes is used to exemplify the coding and correlation processing among FO-CDMA user codes. Cooperating with TDMA and the tunable FBG coding devices, it can support more users without mass-deploying coding devices. Instead of making a direct correlation operation, we configure an FBG decoder scheme on the basis of orthogonal correlation functions of nearly orthogonal m-sequence codes. With the devised FBG decoder architecture, an intended receiver user that operates on the defined orthogonal correlation functions will reject any interfering user and obtain a complete orthogonality between the FO-CDMA users in the system. We also show that this devised system can provide a simple error detecting function.
{"title":"Tunable fiber Bragg grating-based a pair of m-sequence coding for optical CDMA","authors":"D. Hsu","doi":"10.1109/ISCC.2002.1021752","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021752","url":null,"abstract":"A fiber-optical code-division multiple-access (FO-CDMA) scheme, which is based on spectral coding, is proposed. The spectral coding is based on the pseudo-orthogonality of FO-CDMA codes properly written in the fiber Bragg grating (FBG) devices. A pair of maximal-length sequence codes is used to exemplify the coding and correlation processing among FO-CDMA user codes. Cooperating with TDMA and the tunable FBG coding devices, it can support more users without mass-deploying coding devices. Instead of making a direct correlation operation, we configure an FBG decoder scheme on the basis of orthogonal correlation functions of nearly orthogonal m-sequence codes. With the devised FBG decoder architecture, an intended receiver user that operates on the defined orthogonal correlation functions will reject any interfering user and obtain a complete orthogonality between the FO-CDMA users in the system. We also show that this devised system can provide a simple error detecting function.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"111 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113991718","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021685
S. Guan, W. Liu, K. Ong
A self-modifiable color Petri net model (SMCPN) that has multimedia synchronization capability is proposed in this paper. By introducing color tokens associated with basic commands, this model can handle user interaction flexibility. By combining numbers with the color tokens, SMCPN allows iteration to be modeled and hence is able to reduce the graph sizes of synchronous playback models while allowing greater details to be shown. SMCPN can also be used in the design and modeling of a multimedia tool with Memex functions like forward, backward, and trail history functions in a Web browser.
{"title":"An extendible Petri net model for Memex-like applications","authors":"S. Guan, W. Liu, K. Ong","doi":"10.1109/ISCC.2002.1021685","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021685","url":null,"abstract":"A self-modifiable color Petri net model (SMCPN) that has multimedia synchronization capability is proposed in this paper. By introducing color tokens associated with basic commands, this model can handle user interaction flexibility. By combining numbers with the color tokens, SMCPN allows iteration to be modeled and hence is able to reduce the graph sizes of synchronous playback models while allowing greater details to be shown. SMCPN can also be used in the design and modeling of a multimedia tool with Memex functions like forward, backward, and trail history functions in a Web browser.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124127151","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021765
M. Moghaddam, S. M. Safavi
Today's Internet can only support "best effort" traffic while with fast emerging multimedia services, it will become clear that the future Internet architecture will have to support various applications with different quality of service (QoS) requirements. The Differentiated Services (DiffServ) model allows the support of QoS Differentiated Services on an IP backbone network. The DiffServ model provides service classification by means of the Differentiated Service (DS) field in the IP header and the per hop behavior (PHB) observable behavior at the node. In this paper we propose a fuzzy based DiffServ model to implement the Differentiated Services in the Internet. In the proposed model we use a fuzzy meter which is based on a dynamic rate leaky bucket (LB) mechanism. Furthermore we use random early discard (RED) mechanism to provide low loss probability for Assured Services. Simulation results show that the proposed fuzzy DiffServ model has better performance than the conventional DiffServ model with leaky bucket meter.
{"title":"A new FLC based model for Differentiated Services","authors":"M. Moghaddam, S. M. Safavi","doi":"10.1109/ISCC.2002.1021765","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021765","url":null,"abstract":"Today's Internet can only support \"best effort\" traffic while with fast emerging multimedia services, it will become clear that the future Internet architecture will have to support various applications with different quality of service (QoS) requirements. The Differentiated Services (DiffServ) model allows the support of QoS Differentiated Services on an IP backbone network. The DiffServ model provides service classification by means of the Differentiated Service (DS) field in the IP header and the per hop behavior (PHB) observable behavior at the node. In this paper we propose a fuzzy based DiffServ model to implement the Differentiated Services in the Internet. In the proposed model we use a fuzzy meter which is based on a dynamic rate leaky bucket (LB) mechanism. Furthermore we use random early discard (RED) mechanism to provide low loss probability for Assured Services. Simulation results show that the proposed fuzzy DiffServ model has better performance than the conventional DiffServ model with leaky bucket meter.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131356255","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021678
D. Deniz, N. O. Mohamed
A broadband network (e.g. ATM or B-ISDN) node with m-channels of equal capacity and two types of customer arrivals under the complete sharing (CS) call admission control (CAC) strategy is analyzed. The two customer arrival types are; narrowband (n-type) which requires 1 channel (basic bandwidth unit, BBU) and wideband, (w-type) which requires b/sub w/ /spl ges/ 1 channels of the m available BBUs. W-type customers are queued in an infinite buffer while n-type customers are served in a "blocked calls cleared" fashion. Neuts' (1994) matrix analytic approach is used in analyzing the system. Neuts presents the solution to the system equations for the case of w-type customers requiring only 1 channel. In this work, this approach is generalized to include the case of w-type customers requiring b/sub w/ > 1 channels. Numerical examples for the blocking probability, the mean waiting time in the queue and the mean server utilization are presented. The analytic results are validated through system simulation. It is shown that both results are in good agreement. Evaluation and computation techniques applicable to the problem are also discussed.
{"title":"Performance evaluation of a CAC strategy for broadband networks","authors":"D. Deniz, N. O. Mohamed","doi":"10.1109/ISCC.2002.1021678","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021678","url":null,"abstract":"A broadband network (e.g. ATM or B-ISDN) node with m-channels of equal capacity and two types of customer arrivals under the complete sharing (CS) call admission control (CAC) strategy is analyzed. The two customer arrival types are; narrowband (n-type) which requires 1 channel (basic bandwidth unit, BBU) and wideband, (w-type) which requires b/sub w/ /spl ges/ 1 channels of the m available BBUs. W-type customers are queued in an infinite buffer while n-type customers are served in a \"blocked calls cleared\" fashion. Neuts' (1994) matrix analytic approach is used in analyzing the system. Neuts presents the solution to the system equations for the case of w-type customers requiring only 1 channel. In this work, this approach is generalized to include the case of w-type customers requiring b/sub w/ > 1 channels. Numerical examples for the blocking probability, the mean waiting time in the queue and the mean server utilization are presented. The analytic results are validated through system simulation. It is shown that both results are in good agreement. Evaluation and computation techniques applicable to the problem are also discussed.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132657129","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 : 2002-07-01DOI: 10.1109/ISCC.2002.1021663
G. Albertengo, Stefano Petroianni
The simulation of complex telecommunication systems, such as satellite-based networks, is seldom sufficient to understand fully their real behavior and to evaluate the quality of service (QoS) perceived by their users. The mean opinion score (MOS) method, widely used to evaluate the perceived QoS, requires the use of a working system, and this is usually not the case for satellites, when studying new protocols and/or new system architectures. A simulator able to replicate in real time the behavior of the system under examination would be very useful: we call it an emulator. This paper describes an emulator for IP data traffic on a single beam GEO satellite, with TDM/TDMA radio links and on-board circuit switch. The emulator has been implemented in the CNIT Radio Communication Laboratory at Politecnico di Torino.
{"title":"On the emulation of geostationary Earth orbit satellite systems","authors":"G. Albertengo, Stefano Petroianni","doi":"10.1109/ISCC.2002.1021663","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021663","url":null,"abstract":"The simulation of complex telecommunication systems, such as satellite-based networks, is seldom sufficient to understand fully their real behavior and to evaluate the quality of service (QoS) perceived by their users. The mean opinion score (MOS) method, widely used to evaluate the perceived QoS, requires the use of a working system, and this is usually not the case for satellites, when studying new protocols and/or new system architectures. A simulator able to replicate in real time the behavior of the system under examination would be very useful: we call it an emulator. This paper describes an emulator for IP data traffic on a single beam GEO satellite, with TDM/TDMA radio links and on-board circuit switch. The emulator has been implemented in the CNIT Radio Communication Laboratory at Politecnico di Torino.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131334374","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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