Pub Date : 2007-09-24DOI: 10.1109/ICCCN.2007.4317808
Souvik Ray, Zhao Zhang
Many P2P-based storage systems use distributed indexing service for searching documents. There are two security issues when the nodes providing the index service are compromised by adversaries. First, the adversaries may delete the indexes or stop the program of indexing service, making the affected documents disappear in the search infrastructure. Second, the adversaries may leak the locations of the storage nodes hosting certain documents, making those nodes the target of DOS attacks. We propose a protocol called SCUBE which addresses these attacks by using secret-sharing based threshold cryptography and the concept of virtual addresses. Our results show that SCUBE performs appreciably well under different attack scenarios and incurs nominal overhead. A working prototype of SCUBE has also been implemented and tested on the Planetlab testbed.
{"title":"SCUBE: A DoS-Resistant Distributed Search Protocol","authors":"Souvik Ray, Zhao Zhang","doi":"10.1109/ICCCN.2007.4317808","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317808","url":null,"abstract":"Many P2P-based storage systems use distributed indexing service for searching documents. There are two security issues when the nodes providing the index service are compromised by adversaries. First, the adversaries may delete the indexes or stop the program of indexing service, making the affected documents disappear in the search infrastructure. Second, the adversaries may leak the locations of the storage nodes hosting certain documents, making those nodes the target of DOS attacks. We propose a protocol called SCUBE which addresses these attacks by using secret-sharing based threshold cryptography and the concept of virtual addresses. Our results show that SCUBE performs appreciably well under different attack scenarios and incurs nominal overhead. A working prototype of SCUBE has also been implemented and tested on the Planetlab testbed.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127294730","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317856
Sergey Gorinsky, Christoph Jechlitschek
File transfer, web download, and many other applications are primarily interested in minimal delay achievable for their messages. In this paper, we investigate allocating the bottleneck link capacity to transmit messages efficiently but fairly. While SRPT (Shortest Remaining Processing Time) is an optimally efficient algorithm that minimizes average delay of messages, large messages might starve under SRPT in heavy load conditions. PS (Processor Sharing) and ViFi (Virtual Finish Time First) are fair but yield higher average delays than under SRPT. We explore the class of fair algorithms further and prove that no online algorithm in this class is optimally efficient. Then, we derive a fair algorithm SFS (Shortest Fair Sojourn) and report extensive experimental evidence that SFS is consistently more efficient than PS and even ViFi during either temporal overload or steady-state operation, with largest benefits achieved when average load is around the bottleneck link capacity. Furthermore, average delay under the fair SFS remains close to the minimum attained under the unfair SRPT.
{"title":"Fair Efficiency, or Low Average Delay without Starvation","authors":"Sergey Gorinsky, Christoph Jechlitschek","doi":"10.1109/ICCCN.2007.4317856","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317856","url":null,"abstract":"File transfer, web download, and many other applications are primarily interested in minimal delay achievable for their messages. In this paper, we investigate allocating the bottleneck link capacity to transmit messages efficiently but fairly. While SRPT (Shortest Remaining Processing Time) is an optimally efficient algorithm that minimizes average delay of messages, large messages might starve under SRPT in heavy load conditions. PS (Processor Sharing) and ViFi (Virtual Finish Time First) are fair but yield higher average delays than under SRPT. We explore the class of fair algorithms further and prove that no online algorithm in this class is optimally efficient. Then, we derive a fair algorithm SFS (Shortest Fair Sojourn) and report extensive experimental evidence that SFS is consistently more efficient than PS and even ViFi during either temporal overload or steady-state operation, with largest benefits achieved when average load is around the bottleneck link capacity. Furthermore, average delay under the fair SFS remains close to the minimum attained under the unfair SRPT.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114460893","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317976
Kai-Chieh Yang, G. Dane, K. El-Maleh
This paper proposes a metric to quantify the effect of the video frame loss according to their impact toward perceived temporal quality. This metric utilizes information obtained from pixel domain and particularly aims at measuring the temporal video quality degradation caused by both regular and irregular frame loss. As one application, the proposed temporal quality metric is used to evaluate the benefit of adaptive thresholding in frame skipping algorithms at the encoder. Temporal quality metric shows high prediction accuracy compared to subjective quality evaluation. Furthermore, it is shown by the experimental results that proposed temporal quality metric precisely differentiates between different frame skipping approaches and can be effectively used to evaluate them. With the help of the proposed quality metric, encoders can be designed to drop frames effectively with minimal perceptual video quality degradation.
{"title":"Temporal Quality Evaluation for Enhancing Compressed Video","authors":"Kai-Chieh Yang, G. Dane, K. El-Maleh","doi":"10.1109/ICCCN.2007.4317976","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317976","url":null,"abstract":"This paper proposes a metric to quantify the effect of the video frame loss according to their impact toward perceived temporal quality. This metric utilizes information obtained from pixel domain and particularly aims at measuring the temporal video quality degradation caused by both regular and irregular frame loss. As one application, the proposed temporal quality metric is used to evaluate the benefit of adaptive thresholding in frame skipping algorithms at the encoder. Temporal quality metric shows high prediction accuracy compared to subjective quality evaluation. Furthermore, it is shown by the experimental results that proposed temporal quality metric precisely differentiates between different frame skipping approaches and can be effectively used to evaluate them. With the help of the proposed quality metric, encoders can be designed to drop frames effectively with minimal perceptual video quality degradation.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121332516","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317993
Norbert Egi, A. Greenhalgh, M. Handley, Mickaël Hoerdt, L. Mathy, Tim Schooley
In this paper, we evaluate the performance of a software IP router forwarding plane inside the Xen virtual machine monitor environment with a view to identifying (some) design issues in Virtual Routers. To this end, we evaluate and compare the forwarding performance of two identical Linux software router configurations, run either above the Xen hypervisor or within vanilla Linux. Even with minimal sized packets, we show that the Xen DomO privileged domain offers near native forwarding performance at the condition that the sollicitation to unpriviledged domains stay minimal, whereas Xen unprivileged domains offer very poor performance in every cases. This shows that an important design principle for virtual router platforms must be to handle all forwarding, for all virtual routers, onto the same forwarding engine, in order to avoid much detrimental per-packet context switching.
{"title":"Evaluating Xen for Router Virtualization","authors":"Norbert Egi, A. Greenhalgh, M. Handley, Mickaël Hoerdt, L. Mathy, Tim Schooley","doi":"10.1109/ICCCN.2007.4317993","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317993","url":null,"abstract":"In this paper, we evaluate the performance of a software IP router forwarding plane inside the Xen virtual machine monitor environment with a view to identifying (some) design issues in Virtual Routers. To this end, we evaluate and compare the forwarding performance of two identical Linux software router configurations, run either above the Xen hypervisor or within vanilla Linux. Even with minimal sized packets, we show that the Xen DomO privileged domain offers near native forwarding performance at the condition that the sollicitation to unpriviledged domains stay minimal, whereas Xen unprivileged domains offer very poor performance in every cases. This shows that an important design principle for virtual router platforms must be to handle all forwarding, for all virtual routers, onto the same forwarding engine, in order to avoid much detrimental per-packet context switching.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126554760","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317910
Chao-Lieh Chen
We propose a dynamic fuzzy logic control (DFLC) for further enhancement of the IEEE 802.11e enhanced distributed channel access (EDCA) function. Although legacy IEEE 802.11 was enhanced by the 802.11e, in wireless networks real-time traffics over the IEEE 802.11e suffer unacceptable quality especially when network state is dynamic. We adopt fuzzy logic for tackling uncertainty in wireless networks. To deal with the dynamics in wireless networks, fuzzy rules with cognitive consequents are adopted. For streaming multimedia objects over wireless networks, the dynamic fuzzy controller tunes the backoff parameters of the EDCA function to meet the dynamic traffic specification (TSPEC), which is defined by upper layers. Moreover, to support cross-layer design, a cross-layer interface is provided to transport the TSPEC to the MAC layer. Analysis and experiments show that the dynamic fuzzy control provides realtime bandwidth allocation and at the same time preserves fairness.
{"title":"IEEE 802.11e EDCA QoS Provisioning with Dynamic Fuzzy Control and Cross-Layer Interface","authors":"Chao-Lieh Chen","doi":"10.1109/ICCCN.2007.4317910","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317910","url":null,"abstract":"We propose a dynamic fuzzy logic control (DFLC) for further enhancement of the IEEE 802.11e enhanced distributed channel access (EDCA) function. Although legacy IEEE 802.11 was enhanced by the 802.11e, in wireless networks real-time traffics over the IEEE 802.11e suffer unacceptable quality especially when network state is dynamic. We adopt fuzzy logic for tackling uncertainty in wireless networks. To deal with the dynamics in wireless networks, fuzzy rules with cognitive consequents are adopted. For streaming multimedia objects over wireless networks, the dynamic fuzzy controller tunes the backoff parameters of the EDCA function to meet the dynamic traffic specification (TSPEC), which is defined by upper layers. Moreover, to support cross-layer design, a cross-layer interface is provided to transport the TSPEC to the MAC layer. Analysis and experiments show that the dynamic fuzzy control provides realtime bandwidth allocation and at the same time preserves fairness.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126578376","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317883
G. Marias, S. Dritsas, M. Theoharidou, John Mallios, D. Gritzalis
Although VoIP provides new ways of communication, at the same time it offers new possibilities for transmitting bulk unsolicited messages and calls, enabling spam over internet telephony (SPIT). The VoIP prevailing protocol is SIP, which it is vulnerable to threats that allow SPIT to be deployed. In this paper we assess the risk of identified threats and vulnerabilities of the SIP protocol. Then, we conduct an analytical survey of already proposed anti-SPIT techniques and we evaluate their effectiveness, in terms of how they deal with the threats and vulnerabilities. Finally, we complete our evaluation by presenting a theoretical evaluation framework, based on additional qualitative and quantitative criteria.
{"title":"SIP Vulnerabilities and Anti-SPIT Mechanisms Assessment","authors":"G. Marias, S. Dritsas, M. Theoharidou, John Mallios, D. Gritzalis","doi":"10.1109/ICCCN.2007.4317883","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317883","url":null,"abstract":"Although VoIP provides new ways of communication, at the same time it offers new possibilities for transmitting bulk unsolicited messages and calls, enabling spam over internet telephony (SPIT). The VoIP prevailing protocol is SIP, which it is vulnerable to threats that allow SPIT to be deployed. In this paper we assess the risk of identified threats and vulnerabilities of the SIP protocol. Then, we conduct an analytical survey of already proposed anti-SPIT techniques and we evaluate their effectiveness, in terms of how they deal with the threats and vulnerabilities. Finally, we complete our evaluation by presenting a theoretical evaluation framework, based on additional qualitative and quantitative criteria.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132520594","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317891
Theodor Richardson, Chin-Tser Huang
Worms are a significant threat to network systems, both through resource consumption and malicious activity. This paper examines the spread of a class of hitlist-based worms that attempt to propagate by searching for address book files on the host system and using the host's mail program to spread to the addresses found. This threat becomes more severe when the worms are assumed to be polymorphic in nature - able to dynamically change their signature to elude capture. Because the method of propagation for these worms is predictable, it is possible to contain their spread through the use of honeytoken e-mail addresses in the client address book. Any e-mail received by the honeytoken address will be immediately recognized as malicious and can therefore be used to flag client machines as infected. This paper provides a complete description of a method to allow for better containment of this class of worms. The results of the proposed method are examined and compared to a previous method of capturing this type of worm.
{"title":"Containing Hitlist-Based Worms with Polymorphic Signatures","authors":"Theodor Richardson, Chin-Tser Huang","doi":"10.1109/ICCCN.2007.4317891","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317891","url":null,"abstract":"Worms are a significant threat to network systems, both through resource consumption and malicious activity. This paper examines the spread of a class of hitlist-based worms that attempt to propagate by searching for address book files on the host system and using the host's mail program to spread to the addresses found. This threat becomes more severe when the worms are assumed to be polymorphic in nature - able to dynamically change their signature to elude capture. Because the method of propagation for these worms is predictable, it is possible to contain their spread through the use of honeytoken e-mail addresses in the client address book. Any e-mail received by the honeytoken address will be immediately recognized as malicious and can therefore be used to flag client machines as infected. This paper provides a complete description of a method to allow for better containment of this class of worms. The results of the proposed method are examined and compared to a previous method of capturing this type of worm.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"115 15","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113945112","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317801
Kwan-Wu Chin
Deafness is a key problem. It erodes the performance gains provided by directional antennas, and introduces a new hidden terminal problem. To address deafness, and hence the hidden terminal problem, we propose SpotMAC. By exploiting narrow or pencil beams, SpotMAC achieves high spatial reuse, throughput and fairness. In addition, pencil beams simplify the collision avoidance process and constrain the hidden terminal problem to a linear topology which can be solved using an inverse RTS/CTS exchange. From extensive simulation studies, we confirm nodes using SpotMAC have several orders of magnitude higher throughput than those using the IEEE 802.11 MAC with omni-directional antenna.
{"title":"SpotMAC: A Pencil-Beam MAC for Wireless Mesh Networks","authors":"Kwan-Wu Chin","doi":"10.1109/ICCCN.2007.4317801","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317801","url":null,"abstract":"Deafness is a key problem. It erodes the performance gains provided by directional antennas, and introduces a new hidden terminal problem. To address deafness, and hence the hidden terminal problem, we propose SpotMAC. By exploiting narrow or pencil beams, SpotMAC achieves high spatial reuse, throughput and fairness. In addition, pencil beams simplify the collision avoidance process and constrain the hidden terminal problem to a linear topology which can be solved using an inverse RTS/CTS exchange. From extensive simulation studies, we confirm nodes using SpotMAC have several orders of magnitude higher throughput than those using the IEEE 802.11 MAC with omni-directional antenna.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128955774","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317822
O. Turkcu, S. Subramaniam
The blocking performance of limited-reconflgurable all-optical networks is investigated in this paper. Reconfigurability is achieved by reconflgurable optical add-drop multiplexers (ROADMs) and tunable transponders. An analytical model is developed adopting a share-per-node model for the sharing of transponders within a reconfigurable node. The set of wavelengths that can be added/dropped at a reconfigurable node depends on the constraints of ROADMs as well as the (possibly limited or narrowly) tunable transponders. The size of the wavelength set to which a transponder is tunable (tuning range), and the number of transponders are the key parameters that affect the blocking. A lightpath request can be established depending on the transponders' ability to tune to the available wavelengths along the route. We call this constraint as wavelength termination constraint. Both analytical and simulation results show that narrowly tunable transponders achieve a similar performance as widely tunable transponders. The effect of the number of transponders or the number of ports of a ROADM on blocking is also investigated.
{"title":"Blocking Analysis of Limited-Reconfigurable Optical Networks","authors":"O. Turkcu, S. Subramaniam","doi":"10.1109/ICCCN.2007.4317822","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317822","url":null,"abstract":"The blocking performance of limited-reconflgurable all-optical networks is investigated in this paper. Reconfigurability is achieved by reconflgurable optical add-drop multiplexers (ROADMs) and tunable transponders. An analytical model is developed adopting a share-per-node model for the sharing of transponders within a reconfigurable node. The set of wavelengths that can be added/dropped at a reconfigurable node depends on the constraints of ROADMs as well as the (possibly limited or narrowly) tunable transponders. The size of the wavelength set to which a transponder is tunable (tuning range), and the number of transponders are the key parameters that affect the blocking. A lightpath request can be established depending on the transponders' ability to tune to the available wavelengths along the route. We call this constraint as wavelength termination constraint. Both analytical and simulation results show that narrowly tunable transponders achieve a similar performance as widely tunable transponders. The effect of the number of transponders or the number of ports of a ROADM on blocking is also investigated.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128496726","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 : 2007-09-24DOI: 10.1109/ICCCN.2007.4317779
R. Kahn
All types of information may be structured as digital objects. These may be subject to rights, require privacy or demand security. Some may be inaccessible without permission (eg. Behind firewalls) may move from place to place, or exist at multiple locations. Some may need to be accessible for very long period of time. An overall framework in which to address these issues will be presented and their revelence to network operations and management will be discussed.
{"title":"Managing Digital Objects on the Internet","authors":"R. Kahn","doi":"10.1109/ICCCN.2007.4317779","DOIUrl":"https://doi.org/10.1109/ICCCN.2007.4317779","url":null,"abstract":"All types of information may be structured as digital objects. These may be subject to rights, require privacy or demand security. Some may be inaccessible without permission (eg. Behind firewalls) may move from place to place, or exist at multiple locations. Some may need to be accessible for very long period of time. An overall framework in which to address these issues will be presented and their revelence to network operations and management will be discussed.","PeriodicalId":388763,"journal":{"name":"2007 16th International Conference on Computer Communications and Networks","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115334506","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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