Anti-spam technology has been developed to the third generation technology, behavior recognition technology. There are many traditional classification models, among which, decision tree model is the one most widely used, and has a good intelligibility. But the absolutely clear attributes does not always exist in real world. This paper proposed a fuzzy decision tree based method for spam behavior recognition. After preprocessing (data discretization, transformation and compression for continuous-value attributes), the attribute subordinating degree is more natural and reasonable to describe the characteristics of behavior. According to knowledge of the fuzzy decision tree by Fuzzy-ID3, spam can be detected and classified spam sender behavior patterns can by analyzed automatically.
{"title":"Fuzzy Decision Tree Based Inference Technology for Spam Behavior Recognition","authors":"Wang Meizhen, L. Zhitang, Zhong Sheng","doi":"10.1109/ISPA.2009.60","DOIUrl":"https://doi.org/10.1109/ISPA.2009.60","url":null,"abstract":"Anti-spam technology has been developed to the third generation technology, behavior recognition technology. There are many traditional classification models, among which, decision tree model is the one most widely used, and has a good intelligibility. But the absolutely clear attributes does not always exist in real world. This paper proposed a fuzzy decision tree based method for spam behavior recognition. After preprocessing (data discretization, transformation and compression for continuous-value attributes), the attribute subordinating degree is more natural and reasonable to describe the characteristics of behavior. According to knowledge of the fuzzy decision tree by Fuzzy-ID3, spam can be detected and classified spam sender behavior patterns can by analyzed automatically.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121020158","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}
Xiangzhen Kong, Jiwei Huang, Chuang Lin, P. Ungsunan
The virtual infrastructure has become more and more popular in the Grid and Cloud computing. With the aggrandizement scale, the management of the resources in virtual infrastructure faces a great technical challenge. To support the upper services effectively, it raises higher requirements for the performance, fault-tolerance and scalability of virtual infrastructure management systems. In this paper, we study the performance, fault-tolerance and scalability of virtual infrastructure management systems with the three typical structures, including centralized, hierarchical and peer-to-peer structures. We give the mathematical definition of the evaluation metrics and give detailed quantitative analysis, and then get several useful conclusions for enhancing the performance, fault-tolerance and scalability, based on the quantitative analysis. We believe that the results of this work will help system architects make informed choices for building virtual infrastructure.
{"title":"Performance, Fault-Tolerance and Scalability Analysis of Virtual Infrastructure Management System","authors":"Xiangzhen Kong, Jiwei Huang, Chuang Lin, P. Ungsunan","doi":"10.1109/ISPA.2009.24","DOIUrl":"https://doi.org/10.1109/ISPA.2009.24","url":null,"abstract":"The virtual infrastructure has become more and more popular in the Grid and Cloud computing. With the aggrandizement scale, the management of the resources in virtual infrastructure faces a great technical challenge. To support the upper services effectively, it raises higher requirements for the performance, fault-tolerance and scalability of virtual infrastructure management systems. In this paper, we study the performance, fault-tolerance and scalability of virtual infrastructure management systems with the three typical structures, including centralized, hierarchical and peer-to-peer structures. We give the mathematical definition of the evaluation metrics and give detailed quantitative analysis, and then get several useful conclusions for enhancing the performance, fault-tolerance and scalability, based on the quantitative analysis. We believe that the results of this work will help system architects make informed choices for building virtual infrastructure.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116381255","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}
In this paper, we propose a scheme that manages the computational resource of virtual machines that are used to host high performance computing applications. Different from the static configuration methodology employed by the state-of-art virtual machine monitors, in our scheme, the virtual machines are automatically configured according to the actual load generated by the applications. NPB, HPL and kernel compilation are chosen as representative high performance computing applications to run inside the virtual machine constructed using our scheme, and the performance of such applications are compared with that obtained from the statically configured virtual machines. The comparison indicates that besides the great flexibility it brings, the performance penalty resulted by our scheme is below 5% in most cases, and the performance of the application running inside the automatically configured virtual machine is even better than that running inside the statically configured ones in some cases.
{"title":"Virtual Machine Resource Management for High Performance Computing Applications","authors":"Zhiyuan Shao, Hai Jin, Yong Li","doi":"10.1109/ISPA.2009.52","DOIUrl":"https://doi.org/10.1109/ISPA.2009.52","url":null,"abstract":"In this paper, we propose a scheme that manages the computational resource of virtual machines that are used to host high performance computing applications. Different from the static configuration methodology employed by the state-of-art virtual machine monitors, in our scheme, the virtual machines are automatically configured according to the actual load generated by the applications. NPB, HPL and kernel compilation are chosen as representative high performance computing applications to run inside the virtual machine constructed using our scheme, and the performance of such applications are compared with that obtained from the statically configured virtual machines. The comparison indicates that besides the great flexibility it brings, the performance penalty resulted by our scheme is below 5% in most cases, and the performance of the application running inside the automatically configured virtual machine is even better than that running inside the statically configured ones in some cases.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122602873","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}
The large sized data sets are replicated in more than one site for the better availability to the nodes in a grid. Downloading the dataset from these replicated locations have practical difficulties, due to network traffic, congestion, frequent change-in performance of the servers, etc. In order to speed up the download, complex server selection techniques, network and server loads are used. However, consistent performance is not guaranteed due to the shared nature of network links of the load on them, which can vary unpredictably. In this paper, we present a bandwidth sensitive co-allocation scheme for parallel downloading in grid economics. Objective of the proposed technique aims to service grid applications efficiently and economically in data grids. With the consideration of cost factor, we present a novel mechanism for server selection, dynamic file decomposition and co-allocation. Under considerations in costs, our mechanism for selections of servers with various techniques combined is able to significantly attenuate economic costs. We compared our scheme with the existing schemes and the preliminary results show notable improvement in overall completion time of data transfer.
{"title":"Bandwidth Sensitive Co-allocation Scheme for Parallel Downloading in Data Grid","authors":"Ching-Hsien Hsu, Chia-Wei Chu, Chih-Hsun Chou","doi":"10.1109/ISPA.2009.101","DOIUrl":"https://doi.org/10.1109/ISPA.2009.101","url":null,"abstract":"The large sized data sets are replicated in more than one site for the better availability to the nodes in a grid. Downloading the dataset from these replicated locations have practical difficulties, due to network traffic, congestion, frequent change-in performance of the servers, etc. In order to speed up the download, complex server selection techniques, network and server loads are used. However, consistent performance is not guaranteed due to the shared nature of network links of the load on them, which can vary unpredictably. In this paper, we present a bandwidth sensitive co-allocation scheme for parallel downloading in grid economics. Objective of the proposed technique aims to service grid applications efficiently and economically in data grids. With the consideration of cost factor, we present a novel mechanism for server selection, dynamic file decomposition and co-allocation. Under considerations in costs, our mechanism for selections of servers with various techniques combined is able to significantly attenuate economic costs. We compared our scheme with the existing schemes and the preliminary results show notable improvement in overall completion time of data transfer.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122055446","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}
Wei Chen, Hongyi Lu, Li Shen, Zhiying Wang, Nong Xiao
Abstract— Dynamic binary translation (DBT) converts codes written for a source instruction set architecture (ISA) into optimized code for a target ISA. DBT has emerged as an important tool with real world applications. Interpretation is always adopted to handle the non-hotspot code in a two-stage DBT system. An important consideration in such DBT systems is the interpretation overhead. We investigate that repeated redecoding operations are the bottleneck of interpretation overhead. We propose interpreted code cache (Pcache), a hardware assist to save the information of the decoded instruction for reuse. We analyze and model Pcache performance via simulation on a DBT system simulator. Results from SPEC2000 integer benchmarks show that Pcache could significantly reduce redecoding operations and the overhead of interpretation in a DBT system. The speedup of interpretation is up to 17.12 on average with assist of Pcache. We also analyze the extra overhead caused by Pcache, which is neglectable compared to the performance gains.
{"title":"Using Pcache to Speedup Interpretation in Dynamic Binary Translation","authors":"Wei Chen, Hongyi Lu, Li Shen, Zhiying Wang, Nong Xiao","doi":"10.1109/ISPA.2009.83","DOIUrl":"https://doi.org/10.1109/ISPA.2009.83","url":null,"abstract":"Abstract— Dynamic binary translation (DBT) converts codes written for a source instruction set architecture (ISA) into optimized code for a target ISA. DBT has emerged as an important tool with real world applications. Interpretation is always adopted to handle the non-hotspot code in a two-stage DBT system. An important consideration in such DBT systems is the interpretation overhead. We investigate that repeated redecoding operations are the bottleneck of interpretation overhead. We propose interpreted code cache (Pcache), a hardware assist to save the information of the decoded instruction for reuse. We analyze and model Pcache performance via simulation on a DBT system simulator. Results from SPEC2000 integer benchmarks show that Pcache could significantly reduce redecoding operations and the overhead of interpretation in a DBT system. The speedup of interpretation is up to 17.12 on average with assist of Pcache. We also analyze the extra overhead caused by Pcache, which is neglectable compared to the performance gains.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122188181","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}
The task scheduling model and algorithm is very important to achieve high performance for message passing programs. The SPG (Subtask Precedence Graph) model abstracts a task as a set of communication and computation sections so it can explore the dependence among subtasks precisely. The TSSF (Task Section based Scheduling Framework ) is designed to show how to generate subtasks and how to schedule subtasks on to different processors. Based on the SPG model and the TSSF Framework, two TSD(Task Section Duplication based) algorithms, SMU(Searching-Marking- Unmarking) and Scalable SMU are described in detail to show how to get multiple parallel executing paths based on task section duplication. Compared with four typical traditional task scheduling algorithms, the simulation results show that our algorithms outperform other algorithms significantly
{"title":"Optimizing Message Passing Programs Based on Task Section Duplication","authors":"Yin Ye, Zhihui Du, Song Hao","doi":"10.1109/ISPA.2009.98","DOIUrl":"https://doi.org/10.1109/ISPA.2009.98","url":null,"abstract":"The task scheduling model and algorithm is very important to achieve high performance for message passing programs. The SPG (Subtask Precedence Graph) model abstracts a task as a set of communication and computation sections so it can explore the dependence among subtasks precisely. The TSSF (Task Section based Scheduling Framework ) is designed to show how to generate subtasks and how to schedule subtasks on to different processors. Based on the SPG model and the TSSF Framework, two TSD(Task Section Duplication based) algorithms, SMU(Searching-Marking- Unmarking) and Scalable SMU are described in detail to show how to get multiple parallel executing paths based on task section duplication. Compared with four typical traditional task scheduling algorithms, the simulation results show that our algorithms outperform other algorithms significantly","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129935513","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}
Jie Jiang, L. Fang, Jun Wen, Guofu Wu, He-ying Zhang
In energy constrained wireless sensor networks, node scheduling is an effective approach to improving the energy efficiency and prolonging the network lifetime. In this paper, we propose a distributed, lightweight, and location-unaware scheduling scheme for randomly deployed wireless sensor networks. The basic idea of the scheduling scheme is to organize sensor nodes into disjoint node sets, which work alternately to extend network lifetime effectively. This scheme neither incurs any communication overhead nor relies on expensive localization services. Also we have done thorough mathematical analysis and extensive simulations on the scheme using Poisson point process, a realistic deployment model in large scale randomly deployed sensor networks. Theoretic analysis reveals the internal relationship among the required coverage performance, expected network lifetime, node deployment intensity and failure probability. Impact of normally and uniformly distributed time asynchrony on network coverage quality is also investigated. Simulation results demonstrate that the proposed scheme is resilient to time asynchrony among random sensor nodes.
{"title":"Random Scheduling for Wireless Sensor Networks","authors":"Jie Jiang, L. Fang, Jun Wen, Guofu Wu, He-ying Zhang","doi":"10.1109/ISPA.2009.50","DOIUrl":"https://doi.org/10.1109/ISPA.2009.50","url":null,"abstract":"In energy constrained wireless sensor networks, node scheduling is an effective approach to improving the energy efficiency and prolonging the network lifetime. In this paper, we propose a distributed, lightweight, and location-unaware scheduling scheme for randomly deployed wireless sensor networks. The basic idea of the scheduling scheme is to organize sensor nodes into disjoint node sets, which work alternately to extend network lifetime effectively. This scheme neither incurs any communication overhead nor relies on expensive localization services. Also we have done thorough mathematical analysis and extensive simulations on the scheme using Poisson point process, a realistic deployment model in large scale randomly deployed sensor networks. Theoretic analysis reveals the internal relationship among the required coverage performance, expected network lifetime, node deployment intensity and failure probability. Impact of normally and uniformly distributed time asynchrony on network coverage quality is also investigated. Simulation results demonstrate that the proposed scheme is resilient to time asynchrony among random sensor nodes.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123921776","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}
Many parallel computer systems installed in computing centers worldwide, which adopts backfilling based job scheduling policies, require that users should provide estimated job execution time when submitting a job to the system. This paper presents an approach, taking advantage of the estimated job execution time, to effectively allocating processors to jobs submitted to a heterogeneous computing grid. The proposed adaptive processor allocation approach was evaluated with simulation studies under various workload and processor speed conditions. The results indicate that the adaptive processor allocation approach can effectively improve the overall system performance, in terms of jobs’ average turnaround time, from two to four times under different conditions, compared to currently used methods.
{"title":"Adaptive Processor Allocation with Estimated Job Execution Time in Heterogeneous Computing Grid","authors":"Kuo-Chan Huang, Kuan-Po Lai, Hsi-Ya Chang","doi":"10.1109/ISPA.2009.46","DOIUrl":"https://doi.org/10.1109/ISPA.2009.46","url":null,"abstract":"Many parallel computer systems installed in computing centers worldwide, which adopts backfilling based job scheduling policies, require that users should provide estimated job execution time when submitting a job to the system. This paper presents an approach, taking advantage of the estimated job execution time, to effectively allocating processors to jobs submitted to a heterogeneous computing grid. The proposed adaptive processor allocation approach was evaluated with simulation studies under various workload and processor speed conditions. The results indicate that the adaptive processor allocation approach can effectively improve the overall system performance, in terms of jobs’ average turnaround time, from two to four times under different conditions, compared to currently used methods.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"416 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124174571","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}
This paper provides a new data fusion mechanism based on regulation and reliability to solve the data conflict problems of multi-source heterogeneous data fusion in traffic information engineering. This mechanism evaluates each data source on historical reliability and data source QoS (Quality of Service), and then gives its reliability result. Users’ reliability on the data source is calculated and dynamically adjusted, then new reliability data of the data source is given, finally the conflict data is fused. The validation of experiment result indicates that the method enhances accuracy and adoption ratio of the collected data in real time greatly.
{"title":"Multi-Source Traffic Data Fusion Method Based on Regulation and Reliability","authors":"Xinhong Wu, Hai Jin","doi":"10.1109/ISPA.2009.15","DOIUrl":"https://doi.org/10.1109/ISPA.2009.15","url":null,"abstract":"This paper provides a new data fusion mechanism based on regulation and reliability to solve the data conflict problems of multi-source heterogeneous data fusion in traffic information engineering. This mechanism evaluates each data source on historical reliability and data source QoS (Quality of Service), and then gives its reliability result. Users’ reliability on the data source is calculated and dynamically adjusted, then new reliability data of the data source is given, finally the conflict data is fused. The validation of experiment result indicates that the method enhances accuracy and adoption ratio of the collected data in real time greatly.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114818369","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 wireless sensor networks (WSNs), how to design routing protocols is very important to gather data efficiently so that the life of the network can be prolonged. A usual concept to collect data by a sink node is to transfer data from sensor nodes to the sink node by multi-hop. However, it gives rise to two problems. The first one is that core sensor nodes being more frequently used to gather data run out of energy sooner than other sensor nodes. As a result, the network loses its service ability, regardless of a large amount of residual energy of the other nodes. The second one is that the network generates unnecessary traffic during data transmission for choosing a proper data sending path. To resolves the problems, we, in this paper, propose a designated path scheme for energy-balanced data aggregation in WSNs. The proposed scheme pre-determines a set of paths and runs them in round-robin fashion so that all the nodes can participate in the workload of gathering data and transferring them to the sink node. With our analytical performance analysis, we show that our designated path scheme is more energy efficient and can prolong the life time of the network, compared with the existing two data–centric routing schemes, i.e., directed diffusion and hierarchical data aggregation (HDA).
{"title":"A Designated Path Scheme for Energy-Efficient Data Aggregation in Wireless Sensor Networks","authors":"Yong-Ki Kim, Rabindra Bista, Jae-Woo Chang","doi":"10.1109/ISPA.2009.91","DOIUrl":"https://doi.org/10.1109/ISPA.2009.91","url":null,"abstract":"For wireless sensor networks (WSNs), how to design routing protocols is very important to gather data efficiently so that the life of the network can be prolonged. A usual concept to collect data by a sink node is to transfer data from sensor nodes to the sink node by multi-hop. However, it gives rise to two problems. The first one is that core sensor nodes being more frequently used to gather data run out of energy sooner than other sensor nodes. As a result, the network loses its service ability, regardless of a large amount of residual energy of the other nodes. The second one is that the network generates unnecessary traffic during data transmission for choosing a proper data sending path. To resolves the problems, we, in this paper, propose a designated path scheme for energy-balanced data aggregation in WSNs. The proposed scheme pre-determines a set of paths and runs them in round-robin fashion so that all the nodes can participate in the workload of gathering data and transferring them to the sink node. With our analytical performance analysis, we show that our designated path scheme is more energy efficient and can prolong the life time of the network, compared with the existing two data–centric routing schemes, i.e., directed diffusion and hierarchical data aggregation (HDA).","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127852816","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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