Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281621
M. Raynal, K. Vidyasankar
Sequential consistency is a consistency criterion for concurrent objects stating that the execution of a multiprocess program is correct if it could have been produced by executing the program on a mono-processor system, preserving the order of the operations of each individual process. Several protocols implementing sequential consistency on top of asynchronous distributed systems have been proposed. They assume that the processes access the shared objects through basic read and write operations. We consider the case where the processes can invoke multiobject operations which can read or write several objects in a single operation atomically. It proposes a particularly simple protocol that guarantees sequentially consistent executions in such a context. The previous sequential consistency protocols, in addition to considering only unary operations, assume either full replication or a central manager storing copies of all the objects. In contrast, the proposed protocol has the noteworthy feature that each object has a separate manager. Interestingly, this provides the protocol with a versatility dimension that allows deriving simple protocols providing sequential consistency or atomic consistency when each operation is on a single object.
{"title":"A distributed implementation of sequential consistency with multi-object operations","authors":"M. Raynal, K. Vidyasankar","doi":"10.1109/ICDCS.2004.1281621","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281621","url":null,"abstract":"Sequential consistency is a consistency criterion for concurrent objects stating that the execution of a multiprocess program is correct if it could have been produced by executing the program on a mono-processor system, preserving the order of the operations of each individual process. Several protocols implementing sequential consistency on top of asynchronous distributed systems have been proposed. They assume that the processes access the shared objects through basic read and write operations. We consider the case where the processes can invoke multiobject operations which can read or write several objects in a single operation atomically. It proposes a particularly simple protocol that guarantees sequentially consistent executions in such a context. The previous sequential consistency protocols, in addition to considering only unary operations, assume either full replication or a central manager storing copies of all the objects. In contrast, the proposed protocol has the noteworthy feature that each object has a separate manager. Interestingly, this provides the protocol with a versatility dimension that allows deriving simple protocols providing sequential consistency or atomic consistency when each operation is on a single object.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121264562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281632
Takuya Tojo, T. Enokido, M. Takizawa
In group communications, multiple processes first establish a group and then each process sends a message to multiple processes while receiving messages from multiple processes in the group. In addition, messages are required to be causally/totally delivered to each process. Due to the limited computation and communication resource, processes cannot send and receive as messages as the processes would like. We newly propose a notification-based data transmission procedure with two-phase slow start (TPSS) to efficiently exchange multimedia messages in a group so as to satisfy QoS requirement. In TPSS, the transmission rate of a process is increased by transmitting redundant data so that no data is lost even if some packets are lost.
{"title":"Notification-based QoS control protocol for multimedia group communication in high-speed networks","authors":"Takuya Tojo, T. Enokido, M. Takizawa","doi":"10.1109/ICDCS.2004.1281632","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281632","url":null,"abstract":"In group communications, multiple processes first establish a group and then each process sends a message to multiple processes while receiving messages from multiple processes in the group. In addition, messages are required to be causally/totally delivered to each process. Due to the limited computation and communication resource, processes cannot send and receive as messages as the processes would like. We newly propose a notification-based data transmission procedure with two-phase slow start (TPSS) to efficiently exchange multimedia messages in a group so as to satisfy QoS requirement. In TPSS, the transmission rate of a process is increased by transmitting redundant data so that no data is lost even if some packets are lost.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"C-26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126481820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281644
S. Ayyorgun, R. Cruz
We propose a new service model based on service curves, which has a loss aspect. In this model, instead of forcing all the packets to meet their deadlines assigned via a service curve, we allow some packets to be dropped. Specifically, the new model is based on guaranteeing at least a certain fraction of the all packets to meet their deadlines assigned via a service curve. The proposed model is composable. We find a necessary and sufficient condition to employ for an efficient connection admission control at a multiplexer to deliver the services according to the new model, via a graph-theoretic approach. A scheduling algorithm to deliver the services as specified by the new service model, at a multiplexer, also exists.
{"title":"A service-curve model with loss and a multiplexing problem","authors":"S. Ayyorgun, R. Cruz","doi":"10.1109/ICDCS.2004.1281644","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281644","url":null,"abstract":"We propose a new service model based on service curves, which has a loss aspect. In this model, instead of forcing all the packets to meet their deadlines assigned via a service curve, we allow some packets to be dropped. Specifically, the new model is based on guaranteeing at least a certain fraction of the all packets to meet their deadlines assigned via a service curve. The proposed model is composable. We find a necessary and sufficient condition to employ for an efficient connection admission control at a multiplexer to deliver the services according to the new model, via a graph-theoretic approach. A scheduling algorithm to deliver the services as specified by the new service model, at a multiplexer, also exists.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130982983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281610
T. Abdelzaher, Gautam H. Thaker, P. Lardieri
This paper generalizes the notion of utilization bounds for schedulability of aperiodic tasks to the case of distributed resource systems. In the basic model, aperiodically arriving tasks are processed by multiple stages of a resource pipeline within end-to-end deadlines. The authors consider a multidimensional space in which each dimension represents the instantaneous utilization of a single stage. A feasible region is derived in this space such that all tasks meet their deadlines as long as pipeline resource consumption remains within the feasible region. The feasible region is a multidimensional extension of the single-resource utilization bound giving rise to a bounding surface in the utilization space rather than a scalar bound. Extensions of the analysis are provided to nonindependent tasks and arbitrary task graphs. We evaluate the performance of admission control using simulation, as well as demonstrate the applicability of these results to task schedulability analysis in the total ship computing environment envisioned by the US navy.
{"title":"A feasible region for meeting aperiodic end-to-end deadlines in resource pipelines","authors":"T. Abdelzaher, Gautam H. Thaker, P. Lardieri","doi":"10.1109/ICDCS.2004.1281610","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281610","url":null,"abstract":"This paper generalizes the notion of utilization bounds for schedulability of aperiodic tasks to the case of distributed resource systems. In the basic model, aperiodically arriving tasks are processed by multiple stages of a resource pipeline within end-to-end deadlines. The authors consider a multidimensional space in which each dimension represents the instantaneous utilization of a single stage. A feasible region is derived in this space such that all tasks meet their deadlines as long as pipeline resource consumption remains within the feasible region. The feasible region is a multidimensional extension of the single-resource utilization bound giving rise to a bounding surface in the utilization space rather than a scalar bound. Extensions of the analysis are provided to nonindependent tasks and arbitrary task graphs. We evaluate the performance of admission control using simulation, as well as demonstrate the applicability of these results to task schedulability analysis in the total ship computing environment envisioned by the US navy.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"452 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125784172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281617
Qixiang Sun, H. Garcia-Molina
Most peer-to-peer (P2P) systems assume that all peers are cooperating for the benefit of the community. However in practice, there is a significant portion of peers who leech resources from the system without contributing any in return. We propose a simple selfish link-based incentive (SLIC) mechanism for unstructured P2P file sharing systems to create an incentive structure where in exchange for better service, peers are encouraged to share more data, give more capacity to handle other peers' queries, and establish more connections to improve the P2P overlay network. Our SLIC algorithm does not require nodes to be altruistic and does not rely on third parties to provide accurate information about other peers. We demonstrate, through simulation, that SLIC's locally selfish and greedy approach is sufficient for the system to evolve into a "good" state.
{"title":"SLIC: a selfish link-based incentive mechanism for unstructured peer-to-peer networks","authors":"Qixiang Sun, H. Garcia-Molina","doi":"10.1109/ICDCS.2004.1281617","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281617","url":null,"abstract":"Most peer-to-peer (P2P) systems assume that all peers are cooperating for the benefit of the community. However in practice, there is a significant portion of peers who leech resources from the system without contributing any in return. We propose a simple selfish link-based incentive (SLIC) mechanism for unstructured P2P file sharing systems to create an incentive structure where in exchange for better service, peers are encouraged to share more data, give more capacity to handle other peers' queries, and establish more connections to improve the P2P overlay network. Our SLIC algorithm does not require nodes to be altruistic and does not rely on third parties to provide accurate information about other peers. We demonstrate, through simulation, that SLIC's locally selfish and greedy approach is sufficient for the system to evolve into a \"good\" state.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124655233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281564
S. M. Pike, P. Sivilotti
Ideally, distributed algorithms isolate the side-effects of faults within local neighborhoods of impact. Failure locality quantifies this concept as the maximum radius of impact caused by a given fault. We present new locality results for the dining philosophers problem subject to crash failures. The optimal crash locality for dining is 0 in synchronous networks, but degrades to 2 in asynchronous networks. Using the eventually-perfect failure detector /spl diams/P , we construct the first known dining algorithms with crash locality 1 under partial synchrony. These algorithms close the failure-locality complexity gap and improve the crash tolerance of resource allocation algorithms in practical networks. We prove the optimality of our results with two fundamental theorems. First, no dining solution using /spl diams/P achieves locality 0. Second, /spl diams/P is the weakest failure detector in the Chandra-Toueg hierarchy to realize locality 1.
{"title":"Dining philosophers with crash locality 1","authors":"S. M. Pike, P. Sivilotti","doi":"10.1109/ICDCS.2004.1281564","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281564","url":null,"abstract":"Ideally, distributed algorithms isolate the side-effects of faults within local neighborhoods of impact. Failure locality quantifies this concept as the maximum radius of impact caused by a given fault. We present new locality results for the dining philosophers problem subject to crash failures. The optimal crash locality for dining is 0 in synchronous networks, but degrades to 2 in asynchronous networks. Using the eventually-perfect failure detector /spl diams/P , we construct the first known dining algorithms with crash locality 1 under partial synchrony. These algorithms close the failure-locality complexity gap and improve the crash tolerance of resource allocation algorithms in practical networks. We prove the optimality of our results with two fundamental theorems. First, no dining solution using /spl diams/P achieves locality 0. Second, /spl diams/P is the weakest failure detector in the Chandra-Toueg hierarchy to realize locality 1.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117060003","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}
We explore the use of compression methods to improve the middleware-based exchange of information in interactive or collaborative distributed applications. In such applications, good compression factors must be accompanied by compression speeds suitable for the data transfer rates sustainable across network links. Our approach combines methods that continuously monitor current network and processor resources and assess compression effectiveness, with techniques that automatically choose suitable compression techniques. The resulting network- and user-aware compression methods are evaluated experimentally across a range of network links and application data, the former ranging from low end links to homes, to wide-area Internet links, to high end links in intranets, the latter including both scientific (binary molecular dynamics data) and commercial (XML) data sets. Results attained demonstrate substantial improvements of this adaptive technique for data compression over non-adaptive approaches, where better compression methods are used when CPU loads are low and/or network links are slow, and where less effective and typically, faster compression techniques are used in high end network infrastructures.
{"title":"Efficient end to end data exchange using configurable compression","authors":"Y. Wiseman, K. Schwan, Patrick M. Widener","doi":"10.1145/1075395.1075396","DOIUrl":"https://doi.org/10.1145/1075395.1075396","url":null,"abstract":"We explore the use of compression methods to improve the middleware-based exchange of information in interactive or collaborative distributed applications. In such applications, good compression factors must be accompanied by compression speeds suitable for the data transfer rates sustainable across network links. Our approach combines methods that continuously monitor current network and processor resources and assess compression effectiveness, with techniques that automatically choose suitable compression techniques. The resulting network- and user-aware compression methods are evaluated experimentally across a range of network links and application data, the former ranging from low end links to homes, to wide-area Internet links, to high end links in intranets, the latter including both scientific (binary molecular dynamics data) and commercial (XML) data sets. Results attained demonstrate substantial improvements of this adaptive technique for data compression over non-adaptive approaches, where better compression methods are used when CPU loads are low and/or network links are slow, and where less effective and typically, faster compression techniques are used in high end network infrastructures.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124464704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281614
SungJin Choi, MaengSoon Baik, C. Hwang
Location management and message delivery protocol is fundamental to the further development of mobile agent systems in a multiregion mobile agent computing environment in order to control mobile agents and guarantee message delivery between them. However, previous works have some problems when they are applied to a multiregion mobile agent computing environment. First, the cost of location management and message delivery is increased relatively. Second, a following problem arises. Finally, cloned mobile agents and parent & child mobile agents don't get dealt with respect to location management and message delivery. We present a HB (home-blackboard) protocol which is a new location management and message delivery protocol for mobile agents in a multiregion mobile agent computing environment. We have implemented the HB protocol. The HB protocol decreases the cost of location management and message delivery and solves the following problem with low communication cost. In addition, the HB protocol deals with the location management and message delivery of cloned and parent & child mobile agents, so that it guarantees message delivery of these mobile agents.
{"title":"Location management & message delivery protocol in multi-region mobile agent computing environment","authors":"SungJin Choi, MaengSoon Baik, C. Hwang","doi":"10.1109/ICDCS.2004.1281614","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281614","url":null,"abstract":"Location management and message delivery protocol is fundamental to the further development of mobile agent systems in a multiregion mobile agent computing environment in order to control mobile agents and guarantee message delivery between them. However, previous works have some problems when they are applied to a multiregion mobile agent computing environment. First, the cost of location management and message delivery is increased relatively. Second, a following problem arises. Finally, cloned mobile agents and parent & child mobile agents don't get dealt with respect to location management and message delivery. We present a HB (home-blackboard) protocol which is a new location management and message delivery protocol for mobile agents in a multiregion mobile agent computing environment. We have implemented the HB protocol. The HB protocol decreases the cost of location management and message delivery and solves the following problem with low communication cost. In addition, the HB protocol deals with the location management and message delivery of cloned and parent & child mobile agents, so that it guarantees message delivery of these mobile agents.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114601725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281586
Chen Wang, Li Xiao, Yunhao Liu, Pei Zheng
To improve the scalability of Gnutella-like unstructured peer-to-peer (P2P) networks, a uniform index caching (UIC) mechanism was suggested in some earlier work. In UIC, query results are cached in all peers along the inverse query path such that the same query of other peers can be replied from their nearby-cached results. However, our experiments show that the UIC method causes a large amount of duplicated and unnecessary caching of items among neighboring peers. Aiming at improving the search efficiency, we propose a distributed caching mechanism, which distributes the cache results among neighboring peers. Furthermore, based on the distributed caching mechanism, an adaptive search approach is built which selectively forwards the query to the peers with a high probability of providing the desired cache results. All the enhancements above are defined in a protocol called distributed caching and adaptive search (DiCAS). In the DiCAS enhanced Gnutella network, all the peers are logically divided into multiple layers, with the character that all the peers in the same layer have the same group ID. The query flooding is restricted in one layer with the matched group ID. Our simulation study shows that, with the help of the index caching and search space division, the DiCAS protocol can significantly reduce the network search traffic in unstructured P2P systems without degrading query success rate.
{"title":"Distributed caching and adaptive search in multilayer P2P networks","authors":"Chen Wang, Li Xiao, Yunhao Liu, Pei Zheng","doi":"10.1109/ICDCS.2004.1281586","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281586","url":null,"abstract":"To improve the scalability of Gnutella-like unstructured peer-to-peer (P2P) networks, a uniform index caching (UIC) mechanism was suggested in some earlier work. In UIC, query results are cached in all peers along the inverse query path such that the same query of other peers can be replied from their nearby-cached results. However, our experiments show that the UIC method causes a large amount of duplicated and unnecessary caching of items among neighboring peers. Aiming at improving the search efficiency, we propose a distributed caching mechanism, which distributes the cache results among neighboring peers. Furthermore, based on the distributed caching mechanism, an adaptive search approach is built which selectively forwards the query to the peers with a high probability of providing the desired cache results. All the enhancements above are defined in a protocol called distributed caching and adaptive search (DiCAS). In the DiCAS enhanced Gnutella network, all the peers are logically divided into multiple layers, with the character that all the peers in the same layer have the same group ID. The query flooding is restricted in one layer with the matched group ID. Our simulation study shows that, with the help of the index caching and search space division, the DiCAS protocol can significantly reduce the network search traffic in unstructured P2P systems without degrading query success rate.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125620349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-03-24DOI: 10.1109/ICDCS.2004.1281578
E. Babkin, A. Sevastianov, A. Shutov, A. Zhdankin
The general principles and implementation details of a graph-oriented transformation of RDF models are described. The approach suggested allows for facilitating the semantic interoperability of data circulated in a distributed software system based on loosely coupled components.
{"title":"An approach to programmable RDF-model transformations","authors":"E. Babkin, A. Sevastianov, A. Shutov, A. Zhdankin","doi":"10.1109/ICDCS.2004.1281578","DOIUrl":"https://doi.org/10.1109/ICDCS.2004.1281578","url":null,"abstract":"The general principles and implementation details of a graph-oriented transformation of RDF models are described. The approach suggested allows for facilitating the semantic interoperability of data circulated in a distributed software system based on loosely coupled components.","PeriodicalId":348300,"journal":{"name":"24th International Conference on Distributed Computing Systems, 2004. Proceedings.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131470412","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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