Pub Date : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762697
Ihsan Shahwan, Ali Muhammed, Muath A. Obaidat, R. Dorsinville
Scheduling is a fundamental component in resource (bandwidth and power) management in NG wireless networks and plays the main role in providing QoS requirements such as delay, throughput and packet loss for different classes of service in 802.16d networks. In this paper we propose a novel scheduling algorithm Strict Priority Based Adaptive modulation and Coding (SP_AMC_Based) that can grantee QoS between different connections belong to different users by the means of cross layer design between MAC and PHY layers in the process of bandwidth allocation to the contrary of most existing protocols that are base solely on MAC layer. Without loss of generality, the protocol serves a number of users with different connections (flows) that have different QoS requirements. The scheduler considers user current channel condition, connection QoS requirement and packet delay to select a user to be scheduled. The proposed scheduling algorithm is investigated through simulation and performance comparison with WFQ[1] scheduler. The results show a better performance of the proposed scheduler compared with WFQ algorithm.
{"title":"WiMax: Cross layer bandwidth allocation Strict Priority Based Adaptive Modulation and Coding","authors":"Ihsan Shahwan, Ali Muhammed, Muath A. Obaidat, R. Dorsinville","doi":"10.1109/ICCITECHNOL.2011.5762697","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762697","url":null,"abstract":"Scheduling is a fundamental component in resource (bandwidth and power) management in NG wireless networks and plays the main role in providing QoS requirements such as delay, throughput and packet loss for different classes of service in 802.16d networks. In this paper we propose a novel scheduling algorithm Strict Priority Based Adaptive modulation and Coding (SP_AMC_Based) that can grantee QoS between different connections belong to different users by the means of cross layer design between MAC and PHY layers in the process of bandwidth allocation to the contrary of most existing protocols that are base solely on MAC layer. Without loss of generality, the protocol serves a number of users with different connections (flows) that have different QoS requirements. The scheduler considers user current channel condition, connection QoS requirement and packet delay to select a user to be scheduled. The proposed scheduling algorithm is investigated through simulation and performance comparison with WFQ[1] scheduler. The results show a better performance of the proposed scheduler compared with WFQ algorithm.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121441823","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762701
M. Ummy, N. Madamopoulos, R. Dorsinville
We propose and demonstrate a simple compact, inexpensive, SOA-based, multi-wavelength tunable (C- to L-band) fiber laser. A C-band design SOA is used, yet multi-wavelength operation either at the C or L-band region is accomplished by exploiting the gain compression phenomena of the SOA. We demonstrate that the wavelength tunability can be achieved either by inserting a variable attenuator inside the cavity of the laser or by changing the reflectivity of the mirrors. We exploit two different kinds of loop mirrors, a Sagnac and a Lyot-Sagnac loop mirror, which perform multiple functions. Stable multi-wavelength operation is achieved at room temperature without temperature compensation techniques, with measured power and the wavelength stability within < ±0.5 dB and ±0.1 nm, respectively.
{"title":"Tunable multi-wavelength SOA based linear cavity fiber laser source for optical communications applications","authors":"M. Ummy, N. Madamopoulos, R. Dorsinville","doi":"10.1109/ICCITECHNOL.2011.5762701","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762701","url":null,"abstract":"We propose and demonstrate a simple compact, inexpensive, SOA-based, multi-wavelength tunable (C- to L-band) fiber laser. A C-band design SOA is used, yet multi-wavelength operation either at the C or L-band region is accomplished by exploiting the gain compression phenomena of the SOA. We demonstrate that the wavelength tunability can be achieved either by inserting a variable attenuator inside the cavity of the laser or by changing the reflectivity of the mirrors. We exploit two different kinds of loop mirrors, a Sagnac and a Lyot-Sagnac loop mirror, which perform multiple functions. Stable multi-wavelength operation is achieved at room temperature without temperature compensation techniques, with measured power and the wavelength stability within < ±0.5 dB and ±0.1 nm, respectively.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114369914","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762659
Samir Mohammad, Patrick Martin, W. Powley
Numerous approaches to storing XML data in relational databases have been proposed that take advantage of the maturity of relational database management systems. Index structures to support these approaches have been developed to speed-up XML query processing. Typical drawbacks of these approaches include the lack of support for twig queries and the large storage requirements for the index structures. In this paper we propose a novel index structure that is compact and effectively supports processing of XML twig queries. Experimental results show that our approach achieves lower response time than similar approaches while using less space to store the XML data.
{"title":"Relational universal index structure for evaluating XML twig queries","authors":"Samir Mohammad, Patrick Martin, W. Powley","doi":"10.1109/ICCITECHNOL.2011.5762659","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762659","url":null,"abstract":"Numerous approaches to storing XML data in relational databases have been proposed that take advantage of the maturity of relational database management systems. Index structures to support these approaches have been developed to speed-up XML query processing. Typical drawbacks of these approaches include the lack of support for twig queries and the large storage requirements for the index structures. In this paper we propose a novel index structure that is compact and effectively supports processing of XML twig queries. Experimental results show that our approach achieves lower response time than similar approaches while using less space to store the XML data.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123032463","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762675
Nashat Abughalieh, K. Steenhaut, A. Nowé
Wireless Sensor Networks (WSNs) consist of a set of small devices with limited energy resources, reduced processing capabilities and a radio frequency communication unit with limited transmission power. In some applications, wireless channels between nodes are prone to high noise and interference, where Automatic Repeat Request (ARQ) techniques are inefficient for the power loss in packets retransmissions. Error Correcting Codes (ECC) can be used to reduce the number of retransmissions. The high processing power and processing time of ECC powerful decoders make it unsuitable to be implemented in sensor nodes. Simple ECC techniques come with high redundancy in the transmitted packets and low correction ability. In this paper we present a powerful ECC technique for sensor networks based on Parallel Concatenation Turbo Codes. The soft-decision iterative decoder is implemented at the base station and a low power turbo encoder and error correction circuit are implemented at the sensor nodes. This approach enhances the reliability of the network communications, while being energy- and delay efficient. We also tested effect of increasing number of communication hops and variant interleaver memory sizes.
{"title":"Adaptive Parallel Concatenation Turbo Codes for Wireless Sensor Networks","authors":"Nashat Abughalieh, K. Steenhaut, A. Nowé","doi":"10.1109/ICCITECHNOL.2011.5762675","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762675","url":null,"abstract":"Wireless Sensor Networks (WSNs) consist of a set of small devices with limited energy resources, reduced processing capabilities and a radio frequency communication unit with limited transmission power. In some applications, wireless channels between nodes are prone to high noise and interference, where Automatic Repeat Request (ARQ) techniques are inefficient for the power loss in packets retransmissions. Error Correcting Codes (ECC) can be used to reduce the number of retransmissions. The high processing power and processing time of ECC powerful decoders make it unsuitable to be implemented in sensor nodes. Simple ECC techniques come with high redundancy in the transmitted packets and low correction ability. In this paper we present a powerful ECC technique for sensor networks based on Parallel Concatenation Turbo Codes. The soft-decision iterative decoder is implemented at the base station and a low power turbo encoder and error correction circuit are implemented at the sensor nodes. This approach enhances the reliability of the network communications, while being energy- and delay efficient. We also tested effect of increasing number of communication hops and variant interleaver memory sizes.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125094507","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762673
H. Higaki
Various ad-hoc routing protocols have been proposed for wireless networks with dense distribution of wireless nodes. For support of multihop transmission in sparse wireless networks, some DTN (delay-tolerant network) routing have been proposed. However, it is difficult to get better tradeoff between communication overhead and reachability of data messages in DTN routing. This paper proposes a novel DTN routing protocol with help of satellite navigation system mounted on vehicles for vehicular ad-hoc networks (VANETs). By transmission of data messages along a driving route detected by the navigation system and recovery from the deviation due to next-hop detection failure, the proposed routing achieves high reachability though no copies of data messages are transmitted.
{"title":"Navigation system based DTN routing in sparse vehicular networks","authors":"H. Higaki","doi":"10.1109/ICCITECHNOL.2011.5762673","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762673","url":null,"abstract":"Various ad-hoc routing protocols have been proposed for wireless networks with dense distribution of wireless nodes. For support of multihop transmission in sparse wireless networks, some DTN (delay-tolerant network) routing have been proposed. However, it is difficult to get better tradeoff between communication overhead and reachability of data messages in DTN routing. This paper proposes a novel DTN routing protocol with help of satellite navigation system mounted on vehicles for vehicular ad-hoc networks (VANETs). By transmission of data messages along a driving route detected by the navigation system and recovery from the deviation due to next-hop detection failure, the proposed routing achieves high reachability though no copies of data messages are transmitted.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128739424","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762699
M. Karam, H. Safa, H. Mneimneh, J. Dargham, H. Mcheick
Web development frameworks (WDFs) that incorporate both Workflow paradigms and the Model View Controller (MVC) [8] are known as WMVC-WFDs. Such frameworks guide the developer in generating the flow of control between the various components. Despite the pressing need for a visual environment to help developers manage the overwhelming number workflows during development, we have not come across any work that addresses this legitimate concern. In this work we describe, in the context of Ruby on Rail (ROR), an abstract model for the visual generation and management of workflows in WMVC-based web application.
结合了工作流范例和模型-视图-控制器(MVC)[8]的Web开发框架(wdf)被称为wmvc - wfd。这样的框架指导开发人员生成不同组件之间的控制流。尽管迫切需要一个可视化的环境来帮助开发人员在开发过程中管理大量的工作流，但我们还没有遇到任何解决这个合理问题的工作。在这项工作中，我们在Ruby on Rail (ROR)的背景下描述了一个抽象模型，用于在基于wmvc的web应用程序中可视化地生成和管理工作流。
{"title":"Visual management of workflows in web development frameworks","authors":"M. Karam, H. Safa, H. Mneimneh, J. Dargham, H. Mcheick","doi":"10.1109/ICCITECHNOL.2011.5762699","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762699","url":null,"abstract":"Web development frameworks (WDFs) that incorporate both Workflow paradigms and the Model View Controller (MVC) [8] are known as WMVC-WFDs. Such frameworks guide the developer in generating the flow of control between the various components. Despite the pressing need for a visual environment to help developers manage the overwhelming number workflows during development, we have not come across any work that addresses this legitimate concern. In this work we describe, in the context of Ruby on Rail (ROR), an abstract model for the visual generation and management of workflows in WMVC-based web application.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125737572","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762680
H. Ramadhan, A. Al-Hosni
A web usage mining and visualization tool for analyzing the efficiency of design and structure of index pages is presented. The tool uses visual views to identify optimal locations for links and classes of links in a page. The tool automatically generates the recommended redesign of the page. Measures used to accomplish that are visit frequencies, time spent, and a combined time and visit approach. Experimental evaluation reported tends to support the usefulness of the tool in achieving its objectives.
{"title":"A visual system for automatically recommending alternative link structures for web pages","authors":"H. Ramadhan, A. Al-Hosni","doi":"10.1109/ICCITECHNOL.2011.5762680","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762680","url":null,"abstract":"A web usage mining and visualization tool for analyzing the efficiency of design and structure of index pages is presented. The tool uses visual views to identify optimal locations for links and classes of links in a page. The tool automatically generates the recommended redesign of the page. Measures used to accomplish that are visit frequencies, time spent, and a combined time and visit approach. Experimental evaluation reported tends to support the usefulness of the tool in achieving its objectives.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130489217","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762677
Entisar S. Alkayal, F. Essa
Many factors affect resource management in computational Grid such as heterogeneous resources, scalability and performance. Computational Grid has adopted web services technology to deal with environmental heterogeneity and to enhance interoperability and scalability. In this paper, we present a Service Oriented Manager (SOM) that can be implemented to manage heterogeneous resources in computational Grid. SOM is designed depending on web service technology to adapt robust, scalable and interoperability requirements by the Grid system. SOM is implemented and evaluated to measure its benefits.
{"title":"Service Oriented Manager in Grid system","authors":"Entisar S. Alkayal, F. Essa","doi":"10.1109/ICCITECHNOL.2011.5762677","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762677","url":null,"abstract":"Many factors affect resource management in computational Grid such as heterogeneous resources, scalability and performance. Computational Grid has adopted web services technology to deal with environmental heterogeneity and to enhance interoperability and scalability. In this paper, we present a Service Oriented Manager (SOM) that can be implemented to manage heterogeneous resources in computational Grid. SOM is designed depending on web service technology to adapt robust, scalable and interoperability requirements by the Grid system. SOM is implemented and evaluated to measure its benefits.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129510401","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762689
R. Qashi, Martin Bogdan, K. Hanssgen
There are real challenges in both the IEEE 802.11 wireless local area network (WLAN) protocol and the medium access control (MAC)-functions providing the required quality-of-service, high throughput and minimum latencies. The IEEE 802.11 layer supports both the distributed coordination function (DCF) and the enhanced DCF (EDCF). The different access categories (AC) within the EDCF can enhance the quality of WLAN. In the current work, two scenarios are investigated; both use the same parameters from the physical (PHY) and MAC layers. In comparison to the DCF, our results show that EDCF offers a significant enhancement for real-time applications (e.g. audio- and video-streaming).
{"title":"Evaluating the QoS of WLANs for the IEEE 802.11 EDCF in real-time applications","authors":"R. Qashi, Martin Bogdan, K. Hanssgen","doi":"10.1109/ICCITECHNOL.2011.5762689","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762689","url":null,"abstract":"There are real challenges in both the IEEE 802.11 wireless local area network (WLAN) protocol and the medium access control (MAC)-functions providing the required quality-of-service, high throughput and minimum latencies. The IEEE 802.11 layer supports both the distributed coordination function (DCF) and the enhanced DCF (EDCF). The different access categories (AC) within the EDCF can enhance the quality of WLAN. In the current work, two scenarios are investigated; both use the same parameters from the physical (PHY) and MAC layers. In comparison to the DCF, our results show that EDCF offers a significant enhancement for real-time applications (e.g. audio- and video-streaming).","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116143145","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 : 2011-03-29DOI: 10.1109/ICCITECHNOL.2011.5762702
M. Slavik, I. Mahgoub
Multi-hop wireless broadcast is a critical component in ad-hoc wireless networks. Vehicular Ad-hoc Networks (VANET) in particular utilize broadcast as a primary communication mechanism in many applications. Such networks exhibit situations of very high node densities so it is important that the broadcast protocols used to support applications on these networks scale well to high densities. This work evaluates existing broadcast protocols in terms of this scalability using both a high-level simulation assuming an ideal medium (WiBDAT) and a standard detailed wireless simulation (JiST/SWANS). Four broadcast methods and protocols, each having been used as a forwarding node selection algorithm in VANET, are chosen for evaluation: stochastic broadcast, distance method, Advanced Adaptive Gossiping (AAG), and Multi-Point Relaying (MPR). Results show a distinct performance difference in terms of rebroadcast efficiency at high densities. Protocols using network topology information, AAG and MPR, become inefficient at high densities. Stochastic broadcast and the distance method, which use neighbor count directly to calculate retransmit thresholds, are shown to be highly adaptive to node density.
{"title":"On the scalability of wireless multi-hop broadcast protocols with respect to density in VANET","authors":"M. Slavik, I. Mahgoub","doi":"10.1109/ICCITECHNOL.2011.5762702","DOIUrl":"https://doi.org/10.1109/ICCITECHNOL.2011.5762702","url":null,"abstract":"Multi-hop wireless broadcast is a critical component in ad-hoc wireless networks. Vehicular Ad-hoc Networks (VANET) in particular utilize broadcast as a primary communication mechanism in many applications. Such networks exhibit situations of very high node densities so it is important that the broadcast protocols used to support applications on these networks scale well to high densities. This work evaluates existing broadcast protocols in terms of this scalability using both a high-level simulation assuming an ideal medium (WiBDAT) and a standard detailed wireless simulation (JiST/SWANS). Four broadcast methods and protocols, each having been used as a forwarding node selection algorithm in VANET, are chosen for evaluation: stochastic broadcast, distance method, Advanced Adaptive Gossiping (AAG), and Multi-Point Relaying (MPR). Results show a distinct performance difference in terms of rebroadcast efficiency at high densities. Protocols using network topology information, AAG and MPR, become inefficient at high densities. Stochastic broadcast and the distance method, which use neighbor count directly to calculate retransmit thresholds, are shown to be highly adaptive to node density.","PeriodicalId":211631,"journal":{"name":"2011 International Conference on Communications and Information Technology (ICCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133969492","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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