Resource discovery is an important problem in unstructured peer-to-peer networks as there is no centralized index where to search for information about resources. The solution for the problem is to use a search algorithm that locates the resources based on the local information about the network. Efficient data sharing in a peer-to-peer system is complicated by uneven node failure, unreliable network connectivity and limited bandwidth. A well-known technique for improving availability is replication. If multiple copies of data exist on independent nodes, then the chances of at least one copy being accessible are increased. Replication increases robustness. In this paper, we present a novel technique based on Q-learning for replicating objects to other nodes.
{"title":"Autonomous Data Replication Using Q-Learning for Unstructured P2P Networks","authors":"S. Thampi, K. C. Sekaran","doi":"10.1109/NCA.2007.11","DOIUrl":"https://doi.org/10.1109/NCA.2007.11","url":null,"abstract":"Resource discovery is an important problem in unstructured peer-to-peer networks as there is no centralized index where to search for information about resources. The solution for the problem is to use a search algorithm that locates the resources based on the local information about the network. Efficient data sharing in a peer-to-peer system is complicated by uneven node failure, unreliable network connectivity and limited bandwidth. A well-known technique for improving availability is replication. If multiple copies of data exist on independent nodes, then the chances of at least one copy being accessible are increased. Replication increases robustness. In this paper, we present a novel technique based on Q-learning for replicating objects to other nodes.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121245450","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}
Wireless sensor networks are a new emerging area where swarm intelligence can be applied with interesting implications. In fact, a strong analogy between unicellular organism colonies and wireless sensor networks can be emphasized: a sensor network can be viewed as a "colony" of simple, scarce resource nodes that, autonomously, are able only to perform simple tasks, but all together can accomplish very complex problems. In this paper we propose a routing protocol with interesting properties: self organization, fault tolerance and environmental adaptation. The proposed protocol was inspired by the well known behavior (in artificial life studies) of "Slime Mold". Such colony of unicellular organisms organizes itself in clusters by pheromone generation and evaporation mechanisms. In a similar manner our protocol manages the data traffic in clusters towards the sink nodes using the gradient concept and reaching high levels of autonomy. We analyze the proposed protocol to examine the performances and the adaptation properties using simulation techniques.
{"title":"A Swarm-based Routing Protocol for Wireless Sensor Networks","authors":"M. Paone, L. Paladina, Dario Bruneo, A. Puliafito","doi":"10.1109/NCA.2007.2","DOIUrl":"https://doi.org/10.1109/NCA.2007.2","url":null,"abstract":"Wireless sensor networks are a new emerging area where swarm intelligence can be applied with interesting implications. In fact, a strong analogy between unicellular organism colonies and wireless sensor networks can be emphasized: a sensor network can be viewed as a \"colony\" of simple, scarce resource nodes that, autonomously, are able only to perform simple tasks, but all together can accomplish very complex problems. In this paper we propose a routing protocol with interesting properties: self organization, fault tolerance and environmental adaptation. The proposed protocol was inspired by the well known behavior (in artificial life studies) of \"Slime Mold\". Such colony of unicellular organisms organizes itself in clusters by pheromone generation and evaporation mechanisms. In a similar manner our protocol manages the data traffic in clusters towards the sink nodes using the gradient concept and reaching high levels of autonomy. We analyze the proposed protocol to examine the performances and the adaptation properties using simulation techniques.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127560051","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}
Leonardo B. Oliveira, Diego F. Aranha, Eduardo Morais, Felipe Daguano, Julio López Hernandez, R. Dahab
After a few years of intense research, wireless sensor networks (WSNs) still demand new secure and cryptographic schemes. On the other hand, the advent of cryptography from pairings has enabled a wide range of novel cryptosystems. In this work we present TinyTate, the first known implementation of pairings for sensor nodes based on the 8-bit/7.3828-MHz ATmega128L microcontroller (e.g., MICA2 and MICAz motes). We then conclude that cryptography from pairings is indeed viable in resource-constrained nodes.
{"title":"TinyTate: Computing the Tate Pairing in Resource-Constrained Sensor Nodes","authors":"Leonardo B. Oliveira, Diego F. Aranha, Eduardo Morais, Felipe Daguano, Julio López Hernandez, R. Dahab","doi":"10.1109/NCA.2007.48","DOIUrl":"https://doi.org/10.1109/NCA.2007.48","url":null,"abstract":"After a few years of intense research, wireless sensor networks (WSNs) still demand new secure and cryptographic schemes. On the other hand, the advent of cryptography from pairings has enabled a wide range of novel cryptosystems. In this work we present TinyTate, the first known implementation of pairings for sensor nodes based on the 8-bit/7.3828-MHz ATmega128L microcontroller (e.g., MICA2 and MICAz motes). We then conclude that cryptography from pairings is indeed viable in resource-constrained nodes.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131168898","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}
Providing processes with an eventual leader service is an important issue when one has to design and implement a middleware layer on top of a failure-prone asynchronous distributed system. This invited lecture investigates this problem. It first shows that such a service cannot be built if the underlying system is fully asynchronous. Then, the paper visits several additional behavioral assumptions that have been proposed in the literature to cope with this impossibility and presents corresponding eventual leader election protocols. This lecture can be seen as a guided tour of the eventual leader service problem, whose aim is to benefit researchers and system engineers working in distributed middleware built on top of asynchronous networks.
{"title":"Eventual Leader Service in Unreliable Asynchronous Systems: Why? How?","authors":"M. Raynal","doi":"10.1109/NCA.2007.19","DOIUrl":"https://doi.org/10.1109/NCA.2007.19","url":null,"abstract":"Providing processes with an eventual leader service is an important issue when one has to design and implement a middleware layer on top of a failure-prone asynchronous distributed system. This invited lecture investigates this problem. It first shows that such a service cannot be built if the underlying system is fully asynchronous. Then, the paper visits several additional behavioral assumptions that have been proposed in the literature to cope with this impossibility and presents corresponding eventual leader election protocols. This lecture can be seen as a guided tour of the eventual leader service problem, whose aim is to benefit researchers and system engineers working in distributed middleware built on top of asynchronous networks.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122927666","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}
Providing high quality-of-service using a single reserved path easily suffers from single link failures. This paper provides a scalable solution, TPmax-R, to tolerate single link failures. TPmax-R is based on an existing method, AvoidPBO-R. TPmax-R reduces the communication cost incurred by AvoidPBO-R to a scalable level. Instead of broadcasting routing information of all the flows in the network, TPmax-R source nodes communicate only link-based information to each other. TPmax-R pairs a reserved primary path with a well chosen unreserved backup path. Conflicts that might occur in the event of failure are predicted and backup paths are chosen to avoid these conflicts. By carefully planning the backup paths, the resulting service quality provided to the flows after re-routing is expected to be very close to that before the failure. Initial simulations show that TPmax-R provides competitive service quality after the failure while using less overhead.
{"title":"Scalable Communication for High Performance and Inexpensive Reliable QoS using Relaxed Recovery","authors":"I. Chen, M. Ito","doi":"10.1109/NCA.2007.38","DOIUrl":"https://doi.org/10.1109/NCA.2007.38","url":null,"abstract":"Providing high quality-of-service using a single reserved path easily suffers from single link failures. This paper provides a scalable solution, TPmax-R, to tolerate single link failures. TPmax-R is based on an existing method, AvoidPBO-R. TPmax-R reduces the communication cost incurred by AvoidPBO-R to a scalable level. Instead of broadcasting routing information of all the flows in the network, TPmax-R source nodes communicate only link-based information to each other. TPmax-R pairs a reserved primary path with a well chosen unreserved backup path. Conflicts that might occur in the event of failure are predicted and backup paths are chosen to avoid these conflicts. By carefully planning the backup paths, the resulting service quality provided to the flows after re-routing is expected to be very close to that before the failure. Initial simulations show that TPmax-R provides competitive service quality after the failure while using less overhead.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117227225","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}
To flexibly explore the trade-offs between storage space and access efficiency in reliable data storage systems, we describe two classes of erasure resilient coding schemes: basic and generalized pyramid codes. The basic pyramid codes can be simply derived from any existing codes, and thus all known efficient encoding/decoding techniques directly apply. The generalized pyramid codes are radically advanced new codes, which can further improve access efficiency and/or reliability upon the basic pyramid codes. We also establish a necessary condition for any failure pattern to be ever recoverable, and show that the generalized pyramid codes are optimal in failure recovery (i.e., the necessary condition is also sufficient, and any failure pattern that is ever recoverable can indeed be recovered).
{"title":"Pyramid Codes: Flexible Schemes to Trade Space for Access Efficiency in Reliable Data Storage Systems","authors":"Cheng Huang, Minghua Chen, Jin Li","doi":"10.1145/2435204.2435207","DOIUrl":"https://doi.org/10.1145/2435204.2435207","url":null,"abstract":"To flexibly explore the trade-offs between storage space and access efficiency in reliable data storage systems, we describe two classes of erasure resilient coding schemes: basic and generalized pyramid codes. The basic pyramid codes can be simply derived from any existing codes, and thus all known efficient encoding/decoding techniques directly apply. The generalized pyramid codes are radically advanced new codes, which can further improve access efficiency and/or reliability upon the basic pyramid codes. We also establish a necessary condition for any failure pattern to be ever recoverable, and show that the generalized pyramid codes are optimal in failure recovery (i.e., the necessary condition is also sufficient, and any failure pattern that is ever recoverable can indeed be recovered).","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131785037","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}
Radhika Niranjan, Ada Gavrilovska, K. Schwan, Priyanka Tembey
Our research addresses "information appliances' used in modern large-scale distributed systems to: (1) virtualize their data flows by applying actions such as filtering, format translation, etc., and (2) separate such actions from enterprise applications' business logic, to make it easier for future service-oriented codes to inter-operate in diverse and dynamic environments. Our specific contribution is the enrichment of runtimes of these appliances with methods for QoS-awareness, thereby giving them the ability to deliver desired levels of QoS even under sudden requirement changes - IQ-appliances. For experimental evaluation, we prototype an IQ-appliance. Measurements demonstrate the feasibility and utility of the approach.
{"title":"Towards IQ-Appliances: Quality-awareness in Information Virtualization","authors":"Radhika Niranjan, Ada Gavrilovska, K. Schwan, Priyanka Tembey","doi":"10.1109/NCA.2007.49","DOIUrl":"https://doi.org/10.1109/NCA.2007.49","url":null,"abstract":"Our research addresses \"information appliances' used in modern large-scale distributed systems to: (1) virtualize their data flows by applying actions such as filtering, format translation, etc., and (2) separate such actions from enterprise applications' business logic, to make it easier for future service-oriented codes to inter-operate in diverse and dynamic environments. Our specific contribution is the enrichment of runtimes of these appliances with methods for QoS-awareness, thereby giving them the ability to deliver desired levels of QoS even under sudden requirement changes - IQ-appliances. For experimental evaluation, we prototype an IQ-appliance. Measurements demonstrate the feasibility and utility of the approach.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123667607","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}
One of the main issues in content-based publish/subscribe (CBPS) systems is how to dynamically determine groups of similar subscriptions to be adopted for exploiting efficient multicast techniques while guaranteeing at the same time the expressiveness of the subscription scheme. In this work, we propose a distributed mechanism which aims at satisfying important requirements of CBPS systems, that are: i) to guarantee the expressiveness of the subscription languages typical of the content-based paradigm, ii) to exploit efficient events dissemination, iii) to maintain the system scalability in terms of nodes and subscriptions, iv) to start an adaptive system reconfiguration despite new incoming subscriptions. One of the main feature of the proposed mechanism is the use of the system state knowledge sharing by system nodes, with the goal of limiting the system overhead in terms of computing, bandwidth and storage resources. Through a set of simulations we demonstrate the efficiency of the proposed solution.
{"title":"Distributed subscriptions clustering with limited knowledge sharing for content-based publish/subscribe systems","authors":"E. Casalicchio, F. Morabito","doi":"10.1109/NCA.2007.16","DOIUrl":"https://doi.org/10.1109/NCA.2007.16","url":null,"abstract":"One of the main issues in content-based publish/subscribe (CBPS) systems is how to dynamically determine groups of similar subscriptions to be adopted for exploiting efficient multicast techniques while guaranteeing at the same time the expressiveness of the subscription scheme. In this work, we propose a distributed mechanism which aims at satisfying important requirements of CBPS systems, that are: i) to guarantee the expressiveness of the subscription languages typical of the content-based paradigm, ii) to exploit efficient events dissemination, iii) to maintain the system scalability in terms of nodes and subscriptions, iv) to start an adaptive system reconfiguration despite new incoming subscriptions. One of the main feature of the proposed mechanism is the use of the system state knowledge sharing by system nodes, with the goal of limiting the system overhead in terms of computing, bandwidth and storage resources. Through a set of simulations we demonstrate the efficiency of the proposed solution.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129442572","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}
Diego Sevilla Ruiz, José M. García, A. Gómez-Skarmeta
The design and implementation of distributed High Performance Computing (HPC) applications is becoming harder as the scale and number of distributed resources and application is growing. Programming abstractions, libraries and frameworks are needed to better overcome that complexity. Moreover, when Quality of Service (QoS) requirements such as load balancing, efficient resource usage and fault tolerance have to be met, the resulting code is harder to develop, maintain, and reuse, as the code for providing the QoS requirements gets normally mixed with the functionality code. Component Technology, on the other hand, allows a better modularity and reusability of applications and even a better support for the development of distributed applications, as those applications can be partitioned in terms of components installed and running (deployed) in the different hosts participating in the system. Components also have requirements in forms of the aforementioned non-functional aspects. In our approach, the code for ensuring these aspects can be automatically generated based on the requirements stated by components and applications, thus leveraging the component implementer of having to deal with these non-functional aspects. In this paper we present the characteristics and the convenience of the generated code for dealing with load balancing, distribution, and fault-tolerance aspects in the context of CORBA-LC. CORBA-LC is a lightweight distributed reflective component model based on CORBA that imposes a peer network model in which the whole network acts as a repository for managing and assigning the whole set of resources: components, CPU cycles, memory, etc.
{"title":"Aspect-Oriented Programing Techniques to support Distribution, Fault Tolerance, and Load Balancing in the CORBA-LC Component Model","authors":"Diego Sevilla Ruiz, José M. García, A. Gómez-Skarmeta","doi":"10.1109/NCA.2007.8","DOIUrl":"https://doi.org/10.1109/NCA.2007.8","url":null,"abstract":"The design and implementation of distributed High Performance Computing (HPC) applications is becoming harder as the scale and number of distributed resources and application is growing. Programming abstractions, libraries and frameworks are needed to better overcome that complexity. Moreover, when Quality of Service (QoS) requirements such as load balancing, efficient resource usage and fault tolerance have to be met, the resulting code is harder to develop, maintain, and reuse, as the code for providing the QoS requirements gets normally mixed with the functionality code. Component Technology, on the other hand, allows a better modularity and reusability of applications and even a better support for the development of distributed applications, as those applications can be partitioned in terms of components installed and running (deployed) in the different hosts participating in the system. Components also have requirements in forms of the aforementioned non-functional aspects. In our approach, the code for ensuring these aspects can be automatically generated based on the requirements stated by components and applications, thus leveraging the component implementer of having to deal with these non-functional aspects. In this paper we present the characteristics and the convenience of the generated code for dealing with load balancing, distribution, and fault-tolerance aspects in the context of CORBA-LC. CORBA-LC is a lightweight distributed reflective component model based on CORBA that imposes a peer network model in which the whole network acts as a repository for managing and assigning the whole set of resources: components, CPU cycles, memory, etc.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121376834","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 assessment of routing protocols for wireless networks is a difficult task, because of the networks' highly dynamic behavior and the absence of benchmarks. However, some of these networks, such as intermittent wireless sensors networks, periodic or cyclic networks, and low earth orbit (LEO) satellites systems, have more predictable dynamics, as the temporal variations in the network topology are somehow deterministic, which may make them easier to study. The graph theoretic model - the evolving graphs - was proposed to help capture the dynamic behavior of these networks, in view of the construction of least cost routing and other algorithms. Our recent experiments showed that evolving graphs have all the potentials to be an effective and powerful tool in the development of routing protocols for dynamic networks. In this paper, we evaluated the shortest journey evolving graph algorithm when used in a routing protocol for MANETs. We use the NS2 network simulator to compare this first implementation to the four well known protocols, namely AODV, DSR, DSDV, and OLSR. In this paper we present simulation results on the energy consumption of the nodes. We also included other EG protocol, namely EGForemost, in the experiments.
{"title":"On the Evaluation of Shortest Journeys in Dynamic Networks","authors":"Afonso Ferreira, A. Goldman, Julian Monteiro","doi":"10.1109/NCA.2007.35","DOIUrl":"https://doi.org/10.1109/NCA.2007.35","url":null,"abstract":"The assessment of routing protocols for wireless networks is a difficult task, because of the networks' highly dynamic behavior and the absence of benchmarks. However, some of these networks, such as intermittent wireless sensors networks, periodic or cyclic networks, and low earth orbit (LEO) satellites systems, have more predictable dynamics, as the temporal variations in the network topology are somehow deterministic, which may make them easier to study. The graph theoretic model - the evolving graphs - was proposed to help capture the dynamic behavior of these networks, in view of the construction of least cost routing and other algorithms. Our recent experiments showed that evolving graphs have all the potentials to be an effective and powerful tool in the development of routing protocols for dynamic networks. In this paper, we evaluated the shortest journey evolving graph algorithm when used in a routing protocol for MANETs. We use the NS2 network simulator to compare this first implementation to the four well known protocols, namely AODV, DSR, DSDV, and OLSR. In this paper we present simulation results on the energy consumption of the nodes. We also included other EG protocol, namely EGForemost, in the experiments.","PeriodicalId":135395,"journal":{"name":"Sixth IEEE International Symposium on Network Computing and Applications (NCA 2007)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115901097","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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