The aim of human activity recognition is to identify what a user or a group of users are doing at a given point in time, for example travelling or working. Activity recognition plays an important role in mobile and ubiquitous computing both as a goal in itself and as an intermediate task in the design of advanced applications. Virtually all existing activity recognition systems for mobile phones base their predictions on location cues. This approach forces the user to disclose personal information such as her home or work area. In this paper, we present a novel activity recognition system called TRAcME (temporal recognition of activities for mobile environments) which recognises generic human activities from large windows of context, Allenpsilas temporal relations and anonymous landmarks. Unlike existing systems, TRAcME handles simultaneous activities and outputs activities which are consistent with each other at the scale of a userpsilas day.
{"title":"TRAcME: Temporal Activity Recognition Using Mobile Phone Data","authors":"Driss Choujaa, Naranker Dulay","doi":"10.1109/EUC.2008.33","DOIUrl":"https://doi.org/10.1109/EUC.2008.33","url":null,"abstract":"The aim of human activity recognition is to identify what a user or a group of users are doing at a given point in time, for example travelling or working. Activity recognition plays an important role in mobile and ubiquitous computing both as a goal in itself and as an intermediate task in the design of advanced applications. Virtually all existing activity recognition systems for mobile phones base their predictions on location cues. This approach forces the user to disclose personal information such as her home or work area. In this paper, we present a novel activity recognition system called TRAcME (temporal recognition of activities for mobile environments) which recognises generic human activities from large windows of context, Allenpsilas temporal relations and anonymous landmarks. Unlike existing systems, TRAcME handles simultaneous activities and outputs activities which are consistent with each other at the scale of a userpsilas day.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131968589","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 structured P2P networks, the heterogeneity of node capacity, the skewness in query pattern and the greedy routing strategy could result in the load imbalance problem. However, existing load balancing algorithms for structured P2P networks mainly focused on handling the heterogeneity among nodes and the skewed workload. To deal with the load imbalance issue caused by the greedy routing strategy, we propose a routing load dispersion (RLD) mechanism for structured P2P networks in this paper. The mechanism manages to disperse the routing load of queries among nodes so that more nodes have a chance to dedicate their capacities for routing. By dispersing the routing load, the RLD mechanism is able to make use of the free capacity in the network and avoid the congestion effectively. We also evaluate the RLD mechanism by extensive simulations and the simulation results demonstrate the effectiveness of RLD mechanism on congestion control under different workload and churn levels.
{"title":"The Effect of Routing-Load Dispersion on Congestion Control in Structured P2P Networks","authors":"Guowei Huang, Zhi Chen, Ying Wu, G. Wu","doi":"10.1109/EUC.2008.131","DOIUrl":"https://doi.org/10.1109/EUC.2008.131","url":null,"abstract":"In structured P2P networks, the heterogeneity of node capacity, the skewness in query pattern and the greedy routing strategy could result in the load imbalance problem. However, existing load balancing algorithms for structured P2P networks mainly focused on handling the heterogeneity among nodes and the skewed workload. To deal with the load imbalance issue caused by the greedy routing strategy, we propose a routing load dispersion (RLD) mechanism for structured P2P networks in this paper. The mechanism manages to disperse the routing load of queries among nodes so that more nodes have a chance to dedicate their capacities for routing. By dispersing the routing load, the RLD mechanism is able to make use of the free capacity in the network and avoid the congestion effectively. We also evaluate the RLD mechanism by extensive simulations and the simulation results demonstrate the effectiveness of RLD mechanism on congestion control under different workload and churn levels.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114803816","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}
R. Azarderakhsh, A. Reyhani-Masoleh, Zine-Eddine Abid
Key management is a major challenge to achieve security in wireless sensor networks. In most of the schemes presented for key management in wireless sensor networks, it is assumed that the sensor nodes have the same capability. The recent research has shown that the survivability of the network can be improved if sensor nodes are grouped in clusters in which a powerful cluster head assigned. However, to gain advantages of clustering in order to find an efficient key management scheme needs more research. In this paper, we investigate the key management in cluster-based wireless sensor networks using both private and public key cryptography. Our goal is to introduce a platform in which public key cryptography is used to establish a secure link between sensor nodes and gateways. Instead of pre-loading a large number of keys into the sensor nodes, each node requests a session key from the gateway to establish a secure link with its neighbors after clustering phase. The security analysis and performance evaluation show that the proposed scheme has significant saving in storage space, transmission overhead, and perfect resilience against node capture.
{"title":"A Key Management Scheme for Cluster Based Wireless Sensor Networks","authors":"R. Azarderakhsh, A. Reyhani-Masoleh, Zine-Eddine Abid","doi":"10.1109/EUC.2008.176","DOIUrl":"https://doi.org/10.1109/EUC.2008.176","url":null,"abstract":"Key management is a major challenge to achieve security in wireless sensor networks. In most of the schemes presented for key management in wireless sensor networks, it is assumed that the sensor nodes have the same capability. The recent research has shown that the survivability of the network can be improved if sensor nodes are grouped in clusters in which a powerful cluster head assigned. However, to gain advantages of clustering in order to find an efficient key management scheme needs more research. In this paper, we investigate the key management in cluster-based wireless sensor networks using both private and public key cryptography. Our goal is to introduce a platform in which public key cryptography is used to establish a secure link between sensor nodes and gateways. Instead of pre-loading a large number of keys into the sensor nodes, each node requests a session key from the gateway to establish a secure link with its neighbors after clustering phase. The security analysis and performance evaluation show that the proposed scheme has significant saving in storage space, transmission overhead, and perfect resilience against node capture.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116092049","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 EPCglobal Network is a network providing a shared view of the disposition of EPC-bearing objects between EPCglobal subscribers, within a relevant business context. In the EPCglobal Network, product data is distributed to several EPCISes(EPC Information Services) via movement of the product. The ONS (Object Naming Service) and the EPCISDS (EPCIS Discovery Service) are used to identify the distributed data for tracing the product. However, there is neither a standard scenario for access to the services when tracing the product nor a defined standard for EPCISDS. This paper suggests a novel architecture for tracing product data with EPCISDS and ONS. Our architecture provides a concrete substructure for product tracing services.
EPCglobal Network是一个网络，在相关的业务环境中，EPCglobal订户之间提供epc承载对象配置的共享视图。在EPC全球网络中，产品数据通过产品的移动分发到几个EPC信息服务(EPC Information Services)。使用ONS(对象命名服务)和EPCISDS (EPCIS发现服务)来识别分布式数据，以便跟踪产品。但是，在跟踪产品时既没有访问服务的标准场景，也没有为EPCISDS定义的标准。本文提出了一种利用EPCISDS和ONS跟踪产品数据的新体系结构。我们的体系结构为产品跟踪服务提供了具体的子结构。
{"title":"Discovery Architecture for the Tracing of Products in the EPCglobal Network","authors":"Gyeongtaek Lee, J. Shin, Dae-Won Park, H. Kwon","doi":"10.1109/EUC.2008.69","DOIUrl":"https://doi.org/10.1109/EUC.2008.69","url":null,"abstract":"The EPCglobal Network is a network providing a shared view of the disposition of EPC-bearing objects between EPCglobal subscribers, within a relevant business context. In the EPCglobal Network, product data is distributed to several EPCISes(EPC Information Services) via movement of the product. The ONS (Object Naming Service) and the EPCISDS (EPCIS Discovery Service) are used to identify the distributed data for tracing the product. However, there is neither a standard scenario for access to the services when tracing the product nor a defined standard for EPCISDS. This paper suggests a novel architecture for tracing product data with EPCISDS and ONS. Our architecture provides a concrete substructure for product tracing services.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"11 Suppl 12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116693800","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 present attacks on two improved key distribution protocol with perfect reparability that were presented at ICON 2000. First, we show that the two ldquoattacksrdquo described in their paper are trivial and do not count as attacks at all since they are well-known attacks that apply to any security system. Further, we describe several attacks on both improved protocols, and show that an illegitimate attacker could easily impersonate legitimate parties and have other parties think they are sharing keys with the impersonated party when in fact that party is not present at all.
{"title":"Attacks on Improved Key Distribution Protocols with Perfect Reparability","authors":"R. Phan, B. Goi","doi":"10.1109/EUC.2008.161","DOIUrl":"https://doi.org/10.1109/EUC.2008.161","url":null,"abstract":"In this paper, we present attacks on two improved key distribution protocol with perfect reparability that were presented at ICON 2000. First, we show that the two ldquoattacksrdquo described in their paper are trivial and do not count as attacks at all since they are well-known attacks that apply to any security system. Further, we describe several attacks on both improved protocols, and show that an illegitimate attacker could easily impersonate legitimate parties and have other parties think they are sharing keys with the impersonated party when in fact that party is not present at all.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"17 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123625772","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}
Service discovery, an essential building block of nomadic and ubiquitous computing applications, needs to be secured to be effectively deployed. Centralized and decentralized approaches have been proposed to this end. This paper analyzes the application layer secure matching function using a Markovian performance model in order to analyze the effects of DoS attacks in centralized and decentralized service discovery systems and to assess anti-clogging mechanisms as a protection against such attacks. This study highlights the determinant parameters that should be evaluated for ensuring a scalable and secure service discovery deployment.
{"title":"On the Impact of DoS Attacks on Secure Service Discovery","authors":"S. Trabelsi, G. Urvoy-Keller, Y. Roudier","doi":"10.1109/EUC.2008.182","DOIUrl":"https://doi.org/10.1109/EUC.2008.182","url":null,"abstract":"Service discovery, an essential building block of nomadic and ubiquitous computing applications, needs to be secured to be effectively deployed. Centralized and decentralized approaches have been proposed to this end. This paper analyzes the application layer secure matching function using a Markovian performance model in order to analyze the effects of DoS attacks in centralized and decentralized service discovery systems and to assess anti-clogging mechanisms as a protection against such attacks. This study highlights the determinant parameters that should be evaluated for ensuring a scalable and secure service discovery deployment.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130890964","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}
Yu Huang, X. Ma, Xianping Tao, Jiannong Cao, Jian Lu
Context-awareness is a key issue in pervasive computing. Context-aware applications are prone to the context consistency problem, where applications are confronted with conflicting contexts and cannot decide how to adapt themselves. In pervasive computing environments, users are often willing to accept certain degree of context inconsistency, as long as it can reduce the consistency maintenance cost, e.g., query delay and battery power. However, existing consistency maintenance schemes do not enable the users to make such tradeoffs. To this end, we propose the probabilistic consistency checking for pervasive context (PCCPC) algorithm. Detailed performance analysis shows that PCCPC enables the users to check consistency over arbitrarily specified ratio of context. We also conduct experiments to study the cost reduced by probabilistic checking. The analytical and the experimental results show that PCCPC enables the users to efficiently make tradeoffs between context consistency and the associated checking cost.
{"title":"A Probabilistic Approach to Consistency Checking for Pervasive Context","authors":"Yu Huang, X. Ma, Xianping Tao, Jiannong Cao, Jian Lu","doi":"10.1109/EUC.2008.129","DOIUrl":"https://doi.org/10.1109/EUC.2008.129","url":null,"abstract":"Context-awareness is a key issue in pervasive computing. Context-aware applications are prone to the context consistency problem, where applications are confronted with conflicting contexts and cannot decide how to adapt themselves. In pervasive computing environments, users are often willing to accept certain degree of context inconsistency, as long as it can reduce the consistency maintenance cost, e.g., query delay and battery power. However, existing consistency maintenance schemes do not enable the users to make such tradeoffs. To this end, we propose the probabilistic consistency checking for pervasive context (PCCPC) algorithm. Detailed performance analysis shows that PCCPC enables the users to check consistency over arbitrarily specified ratio of context. We also conduct experiments to study the cost reduced by probabilistic checking. The analytical and the experimental results show that PCCPC enables the users to efficiently make tradeoffs between context consistency and the associated checking cost.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130341037","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}
Sparse matrix vector multiplication (SpMxV) is a core operation in many engineering, scientific and financial applications. Due to the sparse nature of the underlying matrices, irregular memory access patterns and short row lengths often slow down the performance significantly. Past implementations of SpMxV have been reported to be run at 10% or less of the machine's peak capability. In this paper we present a novel hardware support called distTree for efficient SpMxV. It is shown that replacing the column indices of sparse matrices with extra hardware is achievable and yields an average speedup by a factor of two for the suite of benchmarks used. The matrix data set for the distTree is approximately 30% less than that for conventional CSR algorithms so that distTree is beneficial in terms of not only performance but also memory usage. Thorough analysis is done by looking at the correlation between the performance speedups and various matrices properties.
{"title":"Hardware Support for Efficient Sparse Matrix Vector Multiplication","authors":"A. Ku, J.Y. Kuo, Jingling Xue","doi":"10.1109/EUC.2008.154","DOIUrl":"https://doi.org/10.1109/EUC.2008.154","url":null,"abstract":"Sparse matrix vector multiplication (SpMxV) is a core operation in many engineering, scientific and financial applications. Due to the sparse nature of the underlying matrices, irregular memory access patterns and short row lengths often slow down the performance significantly. Past implementations of SpMxV have been reported to be run at 10% or less of the machine's peak capability. In this paper we present a novel hardware support called distTree for efficient SpMxV. It is shown that replacing the column indices of sparse matrices with extra hardware is achievable and yields an average speedup by a factor of two for the suite of benchmarks used. The matrix data set for the distTree is approximately 30% less than that for conventional CSR algorithms so that distTree is beneficial in terms of not only performance but also memory usage. Thorough analysis is done by looking at the correlation between the performance speedups and various matrices properties.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130464458","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}
With the great progress of information technologies, computers are embedded into everywhere to make our daily life convenient, efficient and invisible. In order to utilize this progress for learning, a scheduler system, a Ubiquitous Learning System (ULS) was proposed. ULS contributes a lot to improve studentpsilas learning efficiency. Yet improvement can still be made to the system by using sensor networks. In our new design, we embed various kinds of sensors, like temperature sensor, oxygen sensor, light sensor, into the environment. Based on the information collected by such sensors, decisions can be made by the control center to adjust the environment automatically for learner. Our research result reveals that the improved ULS not only benefited learners to acquire their learning habits but also improve their learning efficiency.
{"title":"An Improved Design of the Ubiquitous Learning System Based on Sensor Networks","authors":"M. Dong, Gongwei Zhang, K. Ota, Song Guo, M. Guo","doi":"10.1109/EUC.2008.169","DOIUrl":"https://doi.org/10.1109/EUC.2008.169","url":null,"abstract":"With the great progress of information technologies, computers are embedded into everywhere to make our daily life convenient, efficient and invisible. In order to utilize this progress for learning, a scheduler system, a Ubiquitous Learning System (ULS) was proposed. ULS contributes a lot to improve studentpsilas learning efficiency. Yet improvement can still be made to the system by using sensor networks. In our new design, we embed various kinds of sensors, like temperature sensor, oxygen sensor, light sensor, into the environment. Based on the information collected by such sensors, decisions can be made by the control center to adjust the environment automatically for learner. Our research result reveals that the improved ULS not only benefited learners to acquire their learning habits but also improve their learning efficiency.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125121968","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}
Compared with rapid technology advancements in multicore processors and rapid changes from computing-intensive to highly data-intensive applications, operating systems have been evolved very slowly for several decades. Application users are facing to two major challenges in today's computing environment. On the top level of the system hierarchy, private and shared caches are equipped for many cores to access concurrently, inevitably causing access conflicts to degrade execution performance. On the bottom level, the performance bottleneck of "memory wall" has been shifted to "disk wall" that is a serious bottleneck for many data- intensive applications. Since processor caches and disk storage are not in the major scope of operating system management, and their increasingly complex operations are not transparent to application users, the above mentioned performance issues have not been effectively addressed at any level of computer systems. We have made a continuous effort to enhance operating systems with two objectives: (1) to well utilize rich but complex resources of multicore processors and (2) to access disk data as fast as possible. At the multicore processor level, we are developing new resource allocation management to improve the effective caching capacity per core and/or per thread, and to minimize congestion in off-chip memory accesses by coordinating memory bandwidth sharing. At the storage level, we enable operating systems to effectively exploit "sequential locality" - for the same amount of data, sequential accesses are several orders of magnitude faster than random accesses in disks. In this talk, related research issues and challenges will be overviewed, and preliminary results will be presented.
{"title":"Research Issues and Challenges to Advance System Software for Multicore Processors and Data-Intensive Applications","authors":"Xiaodong Zhang","doi":"10.1109/EUC.2008.189","DOIUrl":"https://doi.org/10.1109/EUC.2008.189","url":null,"abstract":"Compared with rapid technology advancements in multicore processors and rapid changes from computing-intensive to highly data-intensive applications, operating systems have been evolved very slowly for several decades. Application users are facing to two major challenges in today's computing environment. On the top level of the system hierarchy, private and shared caches are equipped for many cores to access concurrently, inevitably causing access conflicts to degrade execution performance. On the bottom level, the performance bottleneck of \"memory wall\" has been shifted to \"disk wall\" that is a serious bottleneck for many data- intensive applications. Since processor caches and disk storage are not in the major scope of operating system management, and their increasingly complex operations are not transparent to application users, the above mentioned performance issues have not been effectively addressed at any level of computer systems. We have made a continuous effort to enhance operating systems with two objectives: (1) to well utilize rich but complex resources of multicore processors and (2) to access disk data as fast as possible. At the multicore processor level, we are developing new resource allocation management to improve the effective caching capacity per core and/or per thread, and to minimize congestion in off-chip memory accesses by coordinating memory bandwidth sharing. At the storage level, we enable operating systems to effectively exploit \"sequential locality\" - for the same amount of data, sequential accesses are several orders of magnitude faster than random accesses in disks. In this talk, related research issues and challenges will be overviewed, and preliminary results will be presented.","PeriodicalId":430277,"journal":{"name":"2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128421449","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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