Approximately 74% of queries in peer-to-peer file sharing systems return no results, wasting both network bandwidth and computational resources. Considering the popularity of this application, this is a significant problem. We propose to improve the accuracy of query routing by improving how file collections are described and defining how peers organize into groups. Our basic approach is to improve the precision of collection description by having each peer partition its collection and describe each collection independently. Experimental results on real peer-to-peer file sharing data shows that our techniques can reduce routing cost to peer groups by 40% with near-perfect load balance.
{"title":"Improving Conjunctive Query Routing in Unstructured P2P Networks","authors":"Wai Gen Yee, L. Nguyen, O. Frieder","doi":"10.1109/NCA.2010.26","DOIUrl":"https://doi.org/10.1109/NCA.2010.26","url":null,"abstract":"Approximately 74% of queries in peer-to-peer file sharing systems return no results, wasting both network bandwidth and computational resources. Considering the popularity of this application, this is a significant problem. We propose to improve the accuracy of query routing by improving how file collections are described and defining how peers organize into groups. Our basic approach is to improve the precision of collection description by having each peer partition its collection and describe each collection independently. Experimental results on real peer-to-peer file sharing data shows that our techniques can reduce routing cost to peer groups by 40% with near-perfect load balance.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116725098","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}
Malware is code that has malicious intent and is designed for malicious purpose such as stealing confidential data, or obtaining root privileges on a system. The current approach to deal with malware threats such as virus and spyware is to use host based anti-malware software. However, this approach leads to many vulnerable machines since many users don't update their software, their virus signatures, and some even disable their software to avoid the system performance degradation caused by these software. Host based security software require a good deal of administration, with consistent needs for reconfiguration, management, and report analysis. With security administrators supporting an ever growing number of users, such an approach has become impractical. In this paper, we present a novel network based malware detection architecture that uses host security vectors to protect host machines without any intervention from hosts. This architecture provides another layer of security and can complement existing host based solutions. Only central detection server needs to be actively managed instead of individual hosts - hence providing more manageable solution for large IT infrastructures.
{"title":"A Network Based Approach to Malware Detection in Large IT Infrastructures","authors":"B. Kumar, C. Katsinis","doi":"10.1109/NCA.2010.33","DOIUrl":"https://doi.org/10.1109/NCA.2010.33","url":null,"abstract":"Malware is code that has malicious intent and is designed for malicious purpose such as stealing confidential data, or obtaining root privileges on a system. The current approach to deal with malware threats such as virus and spyware is to use host based anti-malware software. However, this approach leads to many vulnerable machines since many users don't update their software, their virus signatures, and some even disable their software to avoid the system performance degradation caused by these software. Host based security software require a good deal of administration, with consistent needs for reconfiguration, management, and report analysis. With security administrators supporting an ever growing number of users, such an approach has become impractical. In this paper, we present a novel network based malware detection architecture that uses host security vectors to protect host machines without any intervention from hosts. This architecture provides another layer of security and can complement existing host based solutions. Only central detection server needs to be actively managed instead of individual hosts - hence providing more manageable solution for large IT infrastructures.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132284632","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}
Existing data management schemes in clouds are mainly based on Google File System (GFS) and MapReduce. Problems arise when data partitioning among numerous available nodes therein. This research paper explores new methods of partitioning and distributing data, that is, resource virtualization in cloud computing. Loosely-coupled associative computing techniques, which have so far not been considered for clouds, can provide the break through needed for their data management. Applications based on associative computing models can efficiently utilize the underlying hardware to scale up and down the system resources dynamically. In doing so, the main hurdle towards providing scalable partitioning and distribution of data in the clouds is removed, bringing forth a vastly superior solution for virtualizing data intensive applications and the system infrastructure to support pay on per-use basis.
现有的云数据管理方案主要基于Google File System (GFS)和MapReduce。当数据在其中的许多可用节点之间进行分区时，就会出现问题。本文探讨了云计算中数据分区和分布的新方法，即资源虚拟化。松耦合的关联计算技术迄今尚未被考虑用于云计算，但它可以为云数据管理提供所需的突破。基于关联计算模型的应用程序可以有效地利用底层硬件来动态地扩展和缩减系统资源。通过这样做，消除了在云中提供可伸缩分区和数据分发的主要障碍，为虚拟化数据密集型应用程序和系统基础设施提供了一个非常优越的解决方案，以支持按使用付费。
{"title":"Under the Cloud: A Novel Content Addressable Data Framework for Cloud Parallelization to Create and Virtualize New Breeds of Cloud Applications","authors":"Amir H. Basirat, A. Amin, Asad I. Khan","doi":"10.1109/NCA.2010.29","DOIUrl":"https://doi.org/10.1109/NCA.2010.29","url":null,"abstract":"Existing data management schemes in clouds are mainly based on Google File System (GFS) and MapReduce. Problems arise when data partitioning among numerous available nodes therein. This research paper explores new methods of partitioning and distributing data, that is, resource virtualization in cloud computing. Loosely-coupled associative computing techniques, which have so far not been considered for clouds, can provide the break through needed for their data management. Applications based on associative computing models can efficiently utilize the underlying hardware to scale up and down the system resources dynamically. In doing so, the main hurdle towards providing scalable partitioning and distribution of data in the clouds is removed, bringing forth a vastly superior solution for virtualizing data intensive applications and the system infrastructure to support pay on per-use basis.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115094681","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}
L. Arantes, Pierre Sens, Gaël Thomas, D. Conan, Léon Lim
Mobile ad-hoc networks, MANETs, are self-organized and very dynamic systems where processes have no global knowledge of the system. In this paper, we propose a model that characterizes the dynamics of MANETs in the sense that it considers that paths between nodes are dynamically built and the system can have infinitely many processes but the network may present finite stable partitions. We also propose an algorithm that implements an eventually perfect partition participant detector PD which eventually detects the participant nodes of stable partitions.
{"title":"Partition Participant Detector with Dynamic Paths in Mobile Networks","authors":"L. Arantes, Pierre Sens, Gaël Thomas, D. Conan, Léon Lim","doi":"10.1109/NCA.2010.40","DOIUrl":"https://doi.org/10.1109/NCA.2010.40","url":null,"abstract":"Mobile ad-hoc networks, MANETs, are self-organized and very dynamic systems where processes have no global knowledge of the system. In this paper, we propose a model that characterizes the dynamics of MANETs in the sense that it considers that paths between nodes are dynamically built and the system can have infinitely many processes but the network may present finite stable partitions. We also propose an algorithm that implements an eventually perfect partition participant detector PD which eventually detects the participant nodes of stable partitions.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"3 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132273507","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}
Joseph A. Cooley, R. Khazan, Benjamin Fuller, G. Pickard
We have designed and implemented a general- purpose cryptographic building block, called GROK, for securing communication among groups of entities in networks composed of high-latency, low-bandwidth, intermittently connected links. During the process, we solved a number of non-trivial system problems. This paper describes these problems and our solutions, and motivates and justifies these solutions from three viewpoints: usability, efficiency, and security. The solutions described in this paper have been tempered by securing a widely-used group-oriented application, group text chat. We implemented a prototype extension to a popular text chat client called Pidgin and evaluated it in a real-world scenario. Based on our experiences, these solutions are useful to designers of group-oriented systems specifically, and secure systems in general.
{"title":"GROK: A Practical System for Securing Group Communications","authors":"Joseph A. Cooley, R. Khazan, Benjamin Fuller, G. Pickard","doi":"10.1109/NCA.2010.20","DOIUrl":"https://doi.org/10.1109/NCA.2010.20","url":null,"abstract":"We have designed and implemented a general- purpose cryptographic building block, called GROK, for securing communication among groups of entities in networks composed of high-latency, low-bandwidth, intermittently connected links. During the process, we solved a number of non-trivial system problems. This paper describes these problems and our solutions, and motivates and justifies these solutions from three viewpoints: usability, efficiency, and security. The solutions described in this paper have been tempered by securing a widely-used group-oriented application, group text chat. We implemented a prototype extension to a popular text chat client called Pidgin and evaluated it in a real-world scenario. Based on our experiences, these solutions are useful to designers of group-oriented systems specifically, and secure systems in general.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127317223","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}
Performance management and dependability are two of the fundamental issues in business-critical applications. The ability to detect the occurrence of performance failures and anomalies has raised the attention of researchers in the last years. It is in fact a difficult problem, since a visible change in the performance can result from some natural cause (e.g., workload variations, upgrades) or by some internal anomaly or fault that may end up in a performance failure or application crash. Distinguish between the two scenarios is the goal of the framework presented in this paper. Our framework is targeted for web-based and component-based applications. It makes use of AOP-based monitoring, data correlation techniques and time-series alignment algorithms to spot the occurrence of performance anomalies avoiding false alarms due to workload variations. The paper includes some experimental results that show the effectiveness of our techniques under the occurrence of dynamic workloads and some fault-load situations.
{"title":"Detection of Performance Anomalies in Web-Based Applications","authors":"J. Magalhães, L. Silva","doi":"10.1109/NCA.2010.15","DOIUrl":"https://doi.org/10.1109/NCA.2010.15","url":null,"abstract":"Performance management and dependability are two of the fundamental issues in business-critical applications. The ability to detect the occurrence of performance failures and anomalies has raised the attention of researchers in the last years. It is in fact a difficult problem, since a visible change in the performance can result from some natural cause (e.g., workload variations, upgrades) or by some internal anomaly or fault that may end up in a performance failure or application crash. Distinguish between the two scenarios is the goal of the framework presented in this paper. Our framework is targeted for web-based and component-based applications. It makes use of AOP-based monitoring, data correlation techniques and time-series alignment algorithms to spot the occurrence of performance anomalies avoiding false alarms due to workload variations. The paper includes some experimental results that show the effectiveness of our techniques under the occurrence of dynamic workloads and some fault-load situations.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"123 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127060343","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}
Aiding the efficient collaboration and coordination of rescue teams is a difficult task especially in a mountainous region. Challenges emerge from quickly alerting and debriefing rescuers, to deploying them effectively, and also coordinating and monitoring them in the rural search domain. Knowing the exact location of the rescuers and vehicles involved in a mountain search and rescue mission is a key element for the successful progress of the mission and aids the mission coordinator, who usually stays at the headquarters, to take fast and informed decisions. In this paper we present the devised Location Awareness Rescue System that targets the aforementioned challenges, and provides location information and updates of the rescuers in a real time manner as they are deployed in the rescue domain overlaid onto interactive maps. The results from our tests show that our system is a proficient presence management solution that can provide precise location information by recovering from any periodic or total connectivity loss, and also improve and support mountain rescue teams leading to more effective and successful missions.
{"title":"Location Awareness Rescue System: Support for Mountain Rescue Teams","authors":"Panagiotis Georgopoulos, B. McCarthy, C. Edwards","doi":"10.1109/NCA.2010.44","DOIUrl":"https://doi.org/10.1109/NCA.2010.44","url":null,"abstract":"Aiding the efficient collaboration and coordination of rescue teams is a difficult task especially in a mountainous region. Challenges emerge from quickly alerting and debriefing rescuers, to deploying them effectively, and also coordinating and monitoring them in the rural search domain. Knowing the exact location of the rescuers and vehicles involved in a mountain search and rescue mission is a key element for the successful progress of the mission and aids the mission coordinator, who usually stays at the headquarters, to take fast and informed decisions. In this paper we present the devised Location Awareness Rescue System that targets the aforementioned challenges, and provides location information and updates of the rescuers in a real time manner as they are deployed in the rescue domain overlaid onto interactive maps. The results from our tests show that our system is a proficient presence management solution that can provide precise location information by recovering from any periodic or total connectivity loss, and also improve and support mountain rescue teams leading to more effective and successful missions.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123705150","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}
For a non IT expert to use services in the Cloud is more natural to negotiate the QoS with the provider in terms of service-level metrics --e.g. job deadlines-- instead of resource-level metrics --e.g. CPU MHz. However, current infrastructures only support resource-level metrics --e.g. CPU share and memory allocation-- and there is not a well-known mechanism to translate from service-level metrics to resource-level metrics. Moreover, the lack of precise information regarding the requirements of the services leads to an inefficient resource allocation --usually, providers allocate whole resources to prevent SLA violations. According to this, we propose a novel mechanism to overcome this translation problem using an online prediction system which includes a fast analytical predictor and an adaptive machine learning based predictor. We also show how a deadline scheduler could use these predictions to help providers to make the most of their resources. Our evaluation shows: i) that fast algorithms are able to make predictions with an 11% and 17% of relative error for the CPU and memory respectively; ii) the potential of using accurate predictions in the scheduling compared to simple yet well-known schedulers.
{"title":"Prediction of Job Resource Requirements for Deadline Schedulers to Manage High-Level SLAs on the Cloud","authors":"Gemma Reig, Javier Alonso, Jordi Guitart","doi":"10.1109/NCA.2010.28","DOIUrl":"https://doi.org/10.1109/NCA.2010.28","url":null,"abstract":"For a non IT expert to use services in the Cloud is more natural to negotiate the QoS with the provider in terms of service-level metrics --e.g. job deadlines-- instead of resource-level metrics --e.g. CPU MHz. However, current infrastructures only support resource-level metrics --e.g. CPU share and memory allocation-- and there is not a well-known mechanism to translate from service-level metrics to resource-level metrics. Moreover, the lack of precise information regarding the requirements of the services leads to an inefficient resource allocation --usually, providers allocate whole resources to prevent SLA violations. According to this, we propose a novel mechanism to overcome this translation problem using an online prediction system which includes a fast analytical predictor and an adaptive machine learning based predictor. We also show how a deadline scheduler could use these predictions to help providers to make the most of their resources. Our evaluation shows: i) that fast algorithms are able to make predictions with an 11% and 17% of relative error for the CPU and memory respectively; ii) the potential of using accurate predictions in the scheduling compared to simple yet well-known schedulers.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123039933","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}
B. Kuehne, J. C. Estrella, M. Peixoto, T. C. Tavares, R. Santana, M. J. Santana
This project presents modeling, prototyping and results of the middleware developed for Web service dynamic selection in Web services composition named DWSC-M (Dynamic Web Service Composition Middleware). DWSC-M’s main focus is to choose what Web services will be part of the composite Web services in runtime. The choose is made considering aspects of QoS - Quality of Service. To evalute this approach two algorithms for Web Services selection has been proposed and implemented: the first one uses Random Selection (RS) and the second one uses Euclidean Distance (ED) for the selection of services and considers for this purpose the QoS atributes requested by a client.
{"title":"Dynamic Web Service Composition Middleware: A New Approach for QoS Guarantees","authors":"B. Kuehne, J. C. Estrella, M. Peixoto, T. C. Tavares, R. Santana, M. J. Santana","doi":"10.1109/NCA.2010.30","DOIUrl":"https://doi.org/10.1109/NCA.2010.30","url":null,"abstract":"This project presents modeling, prototyping and results of the middleware developed for Web service dynamic selection in Web services composition named DWSC-M (Dynamic Web Service Composition Middleware). DWSC-M’s main focus is to choose what Web services will be part of the composite Web services in runtime. The choose is made considering aspects of QoS - Quality of Service. To evalute this approach two algorithms for Web Services selection has been proposed and implemented: the first one uses Random Selection (RS) and the second one uses Euclidean Distance (ED) for the selection of services and considers for this purpose the QoS atributes requested by a client.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124839376","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}
Fabien Chaix, D. Avresky, N. Zergainoh, M. Nicolaidis
Future applications will require processors with many cores communicating through a regular interconnection network. Meanwhile, as the Deep submicron technology fore- shadows highly defective chips era, fault-tolerant designs become compulsory. In particular, the fault tolerance of a core interconnect is critical, and inevitably increases its complexity. In this paper, we present a novel adaptive routing algorithm that is able to route messages in the presence of any set of multiple nodes and links failures, as long as a path exists. Compared to the existing solutions, the proposed algorithm provides fault tolerance without using any routing table. It is scalable and can be applied to multicore chips with a 2D mesh core interconnect of any size. The algorithm is deadlock-free and avoids infinite looping in fault-free and faulty 2D meshes, based on Virtual Networks and Virtual Channels. We simulated the proposed algorithm using the worst case scenario, regarding the traffic patterns and the failure rate up to 40%. Experimentation results confirmed that the algorithm tolerates multiple failures even in the most extreme failure patterns. Additionally, we monitored the trade off between the fault tolerance and the average latency for faulty cases, as measurement of the performance degradation. The algorithm detects the interconnects partitioning and enables "preferred paths" for streaming applications.
{"title":"Fault-Tolerant Deadlock-Free Adaptive Routing for Any Set of Link and Node Failures in Multi-cores Systems","authors":"Fabien Chaix, D. Avresky, N. Zergainoh, M. Nicolaidis","doi":"10.1109/NCA.2010.14","DOIUrl":"https://doi.org/10.1109/NCA.2010.14","url":null,"abstract":"Future applications will require processors with many cores communicating through a regular interconnection network. Meanwhile, as the Deep submicron technology fore- shadows highly defective chips era, fault-tolerant designs become compulsory. In particular, the fault tolerance of a core interconnect is critical, and inevitably increases its complexity. In this paper, we present a novel adaptive routing algorithm that is able to route messages in the presence of any set of multiple nodes and links failures, as long as a path exists. Compared to the existing solutions, the proposed algorithm provides fault tolerance without using any routing table. It is scalable and can be applied to multicore chips with a 2D mesh core interconnect of any size. The algorithm is deadlock-free and avoids infinite looping in fault-free and faulty 2D meshes, based on Virtual Networks and Virtual Channels. We simulated the proposed algorithm using the worst case scenario, regarding the traffic patterns and the failure rate up to 40%. Experimentation results confirmed that the algorithm tolerates multiple failures even in the most extreme failure patterns. Additionally, we monitored the trade off between the fault tolerance and the average latency for faulty cases, as measurement of the performance degradation. The algorithm detects the interconnects partitioning and enables \"preferred paths\" for streaming applications.","PeriodicalId":276374,"journal":{"name":"2010 Ninth IEEE International Symposium on Network Computing and Applications","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129572076","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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