Pub Date : 1996-05-27DOI: 10.1109/ICDCS.1996.507919
Wanqing Wu, Madalene Spezialetti, Rajiv Gupta
Distributed programs are often instrumented for collecting information to assist in analyzing the behavior of an application. However, the act of monitoring a process introduces intrusive overhead that delays the times at which actions occur in a monitored execution in comparison to the times at which they occur in an unmonitored execution. These delays can alter the actions of individual processes and the behavior of the system as a whole. The overall behavior of process scheduling is determined by the choices a scheduler makes in terms of when particular processes will be given access to the processor. Monitoring introduced delays can result in different scheduling choices being made which can in turn lead 20 changes in the behavior of processes throughout the distributed system. This paper presents intrusion removal techniques which are designed to accommodate monitoring delays in an attempt to minimize the intrusion on the scheduling and execution behavior of the monitored computation.
{"title":"On-line avoidance of the intrusive effects of monitoring on runtime scheduling decisions","authors":"Wanqing Wu, Madalene Spezialetti, Rajiv Gupta","doi":"10.1109/ICDCS.1996.507919","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507919","url":null,"abstract":"Distributed programs are often instrumented for collecting information to assist in analyzing the behavior of an application. However, the act of monitoring a process introduces intrusive overhead that delays the times at which actions occur in a monitored execution in comparison to the times at which they occur in an unmonitored execution. These delays can alter the actions of individual processes and the behavior of the system as a whole. The overall behavior of process scheduling is determined by the choices a scheduler makes in terms of when particular processes will be given access to the processor. Monitoring introduced delays can result in different scheduling choices being made which can in turn lead 20 changes in the behavior of processes throughout the distributed system. This paper presents intrusion removal techniques which are designed to accommodate monitoring delays in an attempt to minimize the intrusion on the scheduling and execution behavior of the monitored computation.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131535026","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507905
P. Keleher
This paper presents a detailed comparison of the relative importance of allowing concurrent writers versus the choice of the underlying consistency model. Our comparison is based on single- and multiple-writer versions of a lazy release consistent (LRC) protocol, and a single-writer sequentially consistent protocol, all implemented in the CVM software distributed shared memory system. We find that in our environment, which we believe to be representative of distributed systems today and in the near future, the consistency model has a much higher impact on overall performance than the choice of whether to allow concurrent writers. The multiple writer LRC protocol performs an average of 9% better than the single writer LRC protocol, but 34% better than the single-writer sequentially consistent protocol. Set against this, MW-LRC required an average of 72% memory overhead, compared to 10% overhead for the single-writer protocoIs.
{"title":"The relative importance of concurrent writers and weak consistency models","authors":"P. Keleher","doi":"10.1109/ICDCS.1996.507905","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507905","url":null,"abstract":"This paper presents a detailed comparison of the relative importance of allowing concurrent writers versus the choice of the underlying consistency model. Our comparison is based on single- and multiple-writer versions of a lazy release consistent (LRC) protocol, and a single-writer sequentially consistent protocol, all implemented in the CVM software distributed shared memory system. We find that in our environment, which we believe to be representative of distributed systems today and in the near future, the consistency model has a much higher impact on overall performance than the choice of whether to allow concurrent writers. The multiple writer LRC protocol performs an average of 9% better than the single writer LRC protocol, but 34% better than the single-writer sequentially consistent protocol. Set against this, MW-LRC required an average of 72% memory overhead, compared to 10% overhead for the single-writer protocoIs.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133746299","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507924
Lei Tang
We study the transaction atomicity problem for designing electronic payment protocols in distributed systems. We observe that the techniques that are used to guarantee transaction atomicity in a database system are not robust enough to guarantee transaction atomicity in an electronic payment system, in which a set of dishonest or malicious participants may exhibit unpredictable behavior and cause arbitrary failures. We present a new concept-verifiable transaction atomicity-for designing electronic payment protocols. We give formal specifications to the verifiable atomic commitment problem. Then we design a robust electronic currency system to meet the specifications and achieve the verifiable transaction atomicity.
{"title":"Verifiable transaction atomicity for electronic payment protocols","authors":"Lei Tang","doi":"10.1109/ICDCS.1996.507924","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507924","url":null,"abstract":"We study the transaction atomicity problem for designing electronic payment protocols in distributed systems. We observe that the techniques that are used to guarantee transaction atomicity in a database system are not robust enough to guarantee transaction atomicity in an electronic payment system, in which a set of dishonest or malicious participants may exhibit unpredictable behavior and cause arbitrary failures. We present a new concept-verifiable transaction atomicity-for designing electronic payment protocols. We give formal specifications to the verifiable atomic commitment problem. Then we design a robust electronic currency system to meet the specifications and achieve the verifiable transaction atomicity.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133243857","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507911
Seiji Murata, A. Shionozaki, M. Tokoro
Multimedia applications must incorporate real-time task processing over networks. In most cases, there are many receivers for each data stream. Thus, a multicast resource reservation protocol for ensuring timing constraints over the network is required. In this paper, a real-time multicast protocol, called RtMP (Real-time Multicast Protocol) is presented. RtMP provides flexible connection establishment by integrating the multicast routing mechanism and the resource reservation mechanism by defining a generic interface between them. RtMP also provides a mechanism that guarantees service level of established connections according to the sender list. An implementation of RtMP on the real-time OS RT-Mach is also described along with performance evaluation. Finally, a comparison of RtMP with other real-time multicast protocols is given and its efficiency is shown.
{"title":"Integrating routing and resource reservation mechanisms in real-time multicast protocols","authors":"Seiji Murata, A. Shionozaki, M. Tokoro","doi":"10.1109/ICDCS.1996.507911","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507911","url":null,"abstract":"Multimedia applications must incorporate real-time task processing over networks. In most cases, there are many receivers for each data stream. Thus, a multicast resource reservation protocol for ensuring timing constraints over the network is required. In this paper, a real-time multicast protocol, called RtMP (Real-time Multicast Protocol) is presented. RtMP provides flexible connection establishment by integrating the multicast routing mechanism and the resource reservation mechanism by defining a generic interface between them. RtMP also provides a mechanism that guarantees service level of established connections according to the sender list. An implementation of RtMP on the real-time OS RT-Mach is also described along with performance evaluation. Finally, a comparison of RtMP with other real-time multicast protocols is given and its efficiency is shown.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"191 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132633238","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507991
Wenheng Liu, Cho-Li Wang, V. Prasanna
In this paper we develop portable and scalable algorithms for performing irregular all-to-all communication in High Performance Computing (HPC) systems. To minimize the communication latency, the algorithm reduces the total number of messages transmitted, reduces the variance of the lengths of these messages, and overlaps the communication with computation. The performance of the algorithm is characterized using a simple model of HPC systems. Our implementations are performed using the Message Passing Interface (MPI) standard and they can be ported to various HPC platforms. The performance of our algorithms is evaluated on CM5, T3D and SP2. The results show the effectiveness of the techniques as well as the interplay between the architectural features, the machine size, and the variance of message lengths. The experiences of our study can be applied in other HPC systems to optimize the performance of collective communication operations.
{"title":"Portable and scalable algorithms for irregular all-to-all communication","authors":"Wenheng Liu, Cho-Li Wang, V. Prasanna","doi":"10.1109/ICDCS.1996.507991","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507991","url":null,"abstract":"In this paper we develop portable and scalable algorithms for performing irregular all-to-all communication in High Performance Computing (HPC) systems. To minimize the communication latency, the algorithm reduces the total number of messages transmitted, reduces the variance of the lengths of these messages, and overlaps the communication with computation. The performance of the algorithm is characterized using a simple model of HPC systems. Our implementations are performed using the Message Passing Interface (MPI) standard and they can be ported to various HPC platforms. The performance of our algorithms is evaluated on CM5, T3D and SP2. The results show the effectiveness of the techniques as well as the interplay between the architectural features, the machine size, and the variance of message lengths. The experiences of our study can be applied in other HPC systems to optimize the performance of collective communication operations.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117325604","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507987
P. Ferreira, M. Shapiro
We consider a shared store based on distributed shared memory (DSM) supporting persistence by reachability (PBR) a very simple data sharing model for a distributed system. This DSM+PBR model is based on distributed garbage collection (GC). Within a general model for DSM+PBR, we specify a distributed GC algorithm that is efficient and scalable. Its main features are: (i) independent collection of memory subsets (even when replicated), (ii) orthogonal from coherence, (iii) asynchrony, and (iv) a simple heuristic to collect cycles avoiding extra I/O costs. We briefly describe our implementation and show some performance results.
{"title":"Larchant: persistence by reachability in distributed shared memory through garbage collection","authors":"P. Ferreira, M. Shapiro","doi":"10.1109/ICDCS.1996.507987","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507987","url":null,"abstract":"We consider a shared store based on distributed shared memory (DSM) supporting persistence by reachability (PBR) a very simple data sharing model for a distributed system. This DSM+PBR model is based on distributed garbage collection (GC). Within a general model for DSM+PBR, we specify a distributed GC algorithm that is efficient and scalable. Its main features are: (i) independent collection of memory subsets (even when replicated), (ii) orthogonal from coherence, (iii) asynchrony, and (iv) a simple heuristic to collect cycles avoiding extra I/O costs. We briefly describe our implementation and show some performance results.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121748374","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.508005
D. D. Paoli, A. Goscinski, M. Hobbs, P. Joyce
We claim that both remote process creation and process migration are efficient mechanisms to be used in the improvement or development of high performance computer systems. In particular we demonstrate that the claims made by some researchers that process migration is too heavy to be used to support dynamic load balancing are unsubstantiated. We support our claim by presenting these two mechanisms available in the RHODOS distributed operating system, comparing and contrasting these mechanisms and reporting on their performance.
{"title":"Performance comparison of process migration with remote process creation mechanisms in RHODOS","authors":"D. D. Paoli, A. Goscinski, M. Hobbs, P. Joyce","doi":"10.1109/ICDCS.1996.508005","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.508005","url":null,"abstract":"We claim that both remote process creation and process migration are efficient mechanisms to be used in the improvement or development of high performance computer systems. In particular we demonstrate that the claims made by some researchers that process migration is too heavy to be used to support dynamic load balancing are unsubstantiated. We support our claim by presenting these two mechanisms available in the RHODOS distributed operating system, comparing and contrasting these mechanisms and reporting on their performance.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122038111","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.508021
R. Guerraoui, M. Larrea, A. Schiper
Non-blocking atomic commitment protocols enable a decision (commit or abort) to be reached at every correct participant, despite the failure of others. The cost for non-blocking implies however (1) a high number of messages and communication steps required to reach commit, and (2) a complicated termination protocol needed in the case of failure suspicions. In this paper, we present a non-blocking protocol, called MDSPC (Modular and Decentralized Three Phase Commit), which enables to trade resiliency against efficiency. As conveyed by our performance measures, MDSPC is faster than existing non-blocking protocols, and in the case of a broadcast network and a reasonable resiliency rate (e.g. 2 or 3) is almost as efficient as the classical (blocking) 2PC. The termination protocol of MDSPC is encapsulated inside a majority consensus protocol. This modularity leads to a simple structure of MDSPC and enables a precise characterization of its liveness in an asynchronous system with an unreliable failure detector.
{"title":"Reducing the cost for non-blocking in atomic commitment","authors":"R. Guerraoui, M. Larrea, A. Schiper","doi":"10.1109/ICDCS.1996.508021","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.508021","url":null,"abstract":"Non-blocking atomic commitment protocols enable a decision (commit or abort) to be reached at every correct participant, despite the failure of others. The cost for non-blocking implies however (1) a high number of messages and communication steps required to reach commit, and (2) a complicated termination protocol needed in the case of failure suspicions. In this paper, we present a non-blocking protocol, called MDSPC (Modular and Decentralized Three Phase Commit), which enables to trade resiliency against efficiency. As conveyed by our performance measures, MDSPC is faster than existing non-blocking protocols, and in the case of a broadcast network and a reasonable resiliency rate (e.g. 2 or 3) is almost as efficient as the classical (blocking) 2PC. The termination protocol of MDSPC is encapsulated inside a majority consensus protocol. This modularity leads to a simple structure of MDSPC and enables a precise characterization of its liveness in an asynchronous system with an unreliable failure detector.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127233149","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507932
Y. Huang, P. McKinley
We propose a protocol for the construction and maintenance of multipoint connections (MCs). The protocol is based on link-state routing: information regarding multipoint connections is broadcast to network switches, which perform all computations locally. The protocol is generic in that it can be used with MCs of different types, including symmetric MCs, receiver-only MCs, and asymmetric MCs. Results of a simulation study show that this generality can be achieved with negligible (in normal traffic periods) to moderate (in very busy periods) signaling overhead.
{"title":"A generic protocol for multipoint connections under link-state routing","authors":"Y. Huang, P. McKinley","doi":"10.1109/ICDCS.1996.507932","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507932","url":null,"abstract":"We propose a protocol for the construction and maintenance of multipoint connections (MCs). The protocol is based on link-state routing: information regarding multipoint connections is broadcast to network switches, which perform all computations locally. The protocol is generic in that it can be used with MCs of different types, including symmetric MCs, receiver-only MCs, and asymmetric MCs. Results of a simulation study show that this generality can be achieved with negligible (in normal traffic periods) to moderate (in very busy periods) signaling overhead.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126937610","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507897
Yukihiro Hamada, Feng Bao, Aohan Mei, Y. Igarashi
A directed graph G=(V, E) is called the n-rotator graph if V={a/sub 1/a/sub 2//spl middot//spl middot//spl middot/a/sub n/|a/sub 1/a/sub 2//spl middot//spl middot//spl middot/a/sub n/ is a permutation of 1, 2, /spl middot//spl middot//spl middot/, n} and E={(a/sub 1/a/sub 2//spl middot//spl middot//spl middot/a/sub n/, b/sub 1/b/sub 2//spl middot//spl middot//spl middot/b/sub n/) I for some 2/spl les/i/spl les/n, b/sub 1/b/sub 2//spl middot//spl middot//spl middot/b/sub n/=a/sub 2//spl middot//spl middot//spl middot/a/sub i/a/sub 1/a/sub i+1//spl middot//spl middot//spl middot/a/sub n/}. We show that for any pair of distinct nodes in the n-rotator graph, we can construct n-1 disjoint paths, each with length less than 2n, connecting the two nodes. By using these disjoint paths and information dispersal algorithm (IDA) by M.O. Rabin (1989), we design a file transmission scheme and analyse its reliability.
如果V={A /sub 1/ A /sub 2//spl中点//spl中点//spl中点/ A /sub n/| A /sub 1/ A /sub 2//spl中点//spl中点//spl中点/ A /sub n/是1,2，/spl中点//spl中点//spl中点//spl中点//spl中点/，n}和E={(A /sub 1/ A /sub 2//spl中点//spl中点//spl中点/b/sub n/， b/sub 1/b/sub 2//spl中点//spl中点/b/sub n/) I，则有向图G=(V, E)称为n-旋转图，B /sub 1/ B /sub 2//spl middot//spl middot//spl middot//spl middot/ B /sub n/=a/sub 2//spl middot//spl middot//spl middot//spl middot/a/sub i/a/sub 1//spl middot//spl middot/a/sub n/}。我们证明了对于n-rotator图中任意一对不同的节点，我们可以构造n-1条长度小于2n的不相交路径来连接这两个节点。利用这些不相交路径和M.O. Rabin(1989)的信息分散算法(IDA)，我们设计了一个文件传输方案并分析了其可靠性。
{"title":"Fault-tolerant file transmission by information dispersal algorithm in rotator graphs","authors":"Yukihiro Hamada, Feng Bao, Aohan Mei, Y. Igarashi","doi":"10.1109/ICDCS.1996.507897","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507897","url":null,"abstract":"A directed graph G=(V, E) is called the n-rotator graph if V={a/sub 1/a/sub 2//spl middot//spl middot//spl middot/a/sub n/|a/sub 1/a/sub 2//spl middot//spl middot//spl middot/a/sub n/ is a permutation of 1, 2, /spl middot//spl middot//spl middot/, n} and E={(a/sub 1/a/sub 2//spl middot//spl middot//spl middot/a/sub n/, b/sub 1/b/sub 2//spl middot//spl middot//spl middot/b/sub n/) I for some 2/spl les/i/spl les/n, b/sub 1/b/sub 2//spl middot//spl middot//spl middot/b/sub n/=a/sub 2//spl middot//spl middot//spl middot/a/sub i/a/sub 1/a/sub i+1//spl middot//spl middot//spl middot/a/sub n/}. We show that for any pair of distinct nodes in the n-rotator graph, we can construct n-1 disjoint paths, each with length less than 2n, connecting the two nodes. By using these disjoint paths and information dispersal algorithm (IDA) by M.O. Rabin (1989), we design a file transmission scheme and analyse its reliability.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123915173","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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