Pub Date : 2001-02-07DOI: 10.1109/EMPDP.2001.905077
G. Arnold, N. Eicker, T. Lippert, K. Schilling
We compare the performance of a simulation code for lattice quantum electrodynamics, running on the cluster computer ALiCE (Alpha-Linux-Cluster-Engine) and the Cray T3E-1200 system. We present results from simulations using the novel parallelized multicanonical hybrid Monte Carlo algorithm. We merge multicanonical simulation techniques with the hybrid Monte Carlo algorithm to achieve a parallel scheme, and thus to be able to fight the notorious metastabilities by use of high performance parallel computers. We demonstrate for this application field that ALiCE is superior to the Cray T3E-1200 by factors of about 1.3 to 2.
{"title":"Cluster computing vs. Cray T3E-a case study from numerical field theory","authors":"G. Arnold, N. Eicker, T. Lippert, K. Schilling","doi":"10.1109/EMPDP.2001.905077","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905077","url":null,"abstract":"We compare the performance of a simulation code for lattice quantum electrodynamics, running on the cluster computer ALiCE (Alpha-Linux-Cluster-Engine) and the Cray T3E-1200 system. We present results from simulations using the novel parallelized multicanonical hybrid Monte Carlo algorithm. We merge multicanonical simulation techniques with the hybrid Monte Carlo algorithm to achieve a parallel scheme, and thus to be able to fight the notorious metastabilities by use of high performance parallel computers. We demonstrate for this application field that ALiCE is superior to the Cray T3E-1200 by factors of about 1.3 to 2.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129646018","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905036
Tom Gross
Despite huge progress in information and communication technology it is often difficult to spontaneously contact persons who are at other locations. This is often due to the fact that important information about the persons at the other sites is missing. We therefore argue that users need awareness-they need to know if the potential communication or cooperation partners are present in the system, if they are available, how busy they are, and so forth. Furthermore, users need this information independently of their current location and adapted to their current context. In this paper we introduce the concept of ubiquitous awareness-a concept that provides users with context-specific information about the presence, availability, and tasks of other persons anytime and anywhere and at the same time allows the system to capture information about users. We present the PRAVTA prototype that exemplifies an implementation of this concept.
{"title":"Towards ubiquitous awareness: the PRAVTA prototype","authors":"Tom Gross","doi":"10.1109/EMPDP.2001.905036","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905036","url":null,"abstract":"Despite huge progress in information and communication technology it is often difficult to spontaneously contact persons who are at other locations. This is often due to the fact that important information about the persons at the other sites is missing. We therefore argue that users need awareness-they need to know if the potential communication or cooperation partners are present in the system, if they are available, how busy they are, and so forth. Furthermore, users need this information independently of their current location and adapted to their current context. In this paper we introduce the concept of ubiquitous awareness-a concept that provides users with context-specific information about the presence, availability, and tasks of other persons anytime and anywhere and at the same time allows the system to capture information about users. We present the PRAVTA prototype that exemplifies an implementation of this concept.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127019792","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905033
R. Baraglia, R. Perego, J. Hidalgo, J. Lanchares, F. Tirado
In this paper we investigate the design of a compact genetic algorithm to solve multi-FPGA partitioning problems. Nowadays Multi-FPGA systems are used for a great variety of applications such as dynamically reconfigurable hardware applications, digital circuit emulation, and numerical computation. Both a sequential and a parallel version of a compact genetic algorithm (cGA) have been designed and implemented on a cluster of workstations. The peculiarities of the cGA permits to save memory in order to address large multi-FPGA partitioning problems, while the exploitation of parallelism allows to reduce execution times. The good results achieved on several experiments conducted on different multi-FPGA partitioning instances show that this solution is viable to solve multi-FPGA partitioning problems.
{"title":"A parallel compact genetic algorithm for multi-FPGA partitioning","authors":"R. Baraglia, R. Perego, J. Hidalgo, J. Lanchares, F. Tirado","doi":"10.1109/EMPDP.2001.905033","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905033","url":null,"abstract":"In this paper we investigate the design of a compact genetic algorithm to solve multi-FPGA partitioning problems. Nowadays Multi-FPGA systems are used for a great variety of applications such as dynamically reconfigurable hardware applications, digital circuit emulation, and numerical computation. Both a sequential and a parallel version of a compact genetic algorithm (cGA) have been designed and implemented on a cluster of workstations. The peculiarities of the cGA permits to save memory in order to address large multi-FPGA partitioning problems, while the exploitation of parallelism allows to reduce execution times. The good results achieved on several experiments conducted on different multi-FPGA partitioning instances show that this solution is viable to solve multi-FPGA partitioning problems.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131852441","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905068
G. L. Shabgahi, J. Bass, S. Bennett
Voting algorithms have been widely used in the realisation of fault-tolerant systems. We propose a new software voting algorithm which uses the history record of redundant modules to compute the final output. Two versions for the novel algorithm are introduced In the first version any module result is assigned to a weighting value such that module results with higher history record value, are assigned to a higher weighing value than those with lower history record value. In the second version of the novel voter, those module results which have a history record value, less than the average record value, are allocated a weight of zero and removed from the contribution toward the voter output. Furthermore, a novel method for creation of a history record of modules is proposed. Empirical results show that both versions of the novel voter give higher safety performance than the Standard Weighted Average voter with permanent and transient errors.
{"title":"History-based weighted average voter: a novel software voting algorithm for fault-tolerant computer systems","authors":"G. L. Shabgahi, J. Bass, S. Bennett","doi":"10.1109/EMPDP.2001.905068","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905068","url":null,"abstract":"Voting algorithms have been widely used in the realisation of fault-tolerant systems. We propose a new software voting algorithm which uses the history record of redundant modules to compute the final output. Two versions for the novel algorithm are introduced In the first version any module result is assigned to a weighting value such that module results with higher history record value, are assigned to a higher weighing value than those with lower history record value. In the second version of the novel voter, those module results which have a history record value, less than the average record value, are allocated a weight of zero and removed from the contribution toward the voter output. Furthermore, a novel method for creation of a history record of modules is proposed. Empirical results show that both versions of the novel voter give higher safety performance than the Standard Weighted Average voter with permanent and transient errors.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128459644","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905025
P. Sage, P. Milligan, A. Bouridane
It is clear that writing software for parallel architectures is a non-trivial process. This has encouraged much research in an effort to provide tools to assist parallel software development. However, while these tools may cater for architecture-specific problems, they do little for the concept of parallel software engineering, as the end product is usually neither scaleable nor portable. The introduction of a level of abstraction in the expression of parallel algorithms can elevate the reasoning process above architectural constraints and assist the production of more flexible code. This paper outlines an object-oriented parallel algorithm development paradigm based on a task and channel notation, and examines the utilisation of Java TM technologies in the development of a distributed Java TM virtual machine architecture on which algorithms expressed in this notation may be executed dynamically.
{"title":"Dynamic code management on a Java multicomputer","authors":"P. Sage, P. Milligan, A. Bouridane","doi":"10.1109/EMPDP.2001.905025","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905025","url":null,"abstract":"It is clear that writing software for parallel architectures is a non-trivial process. This has encouraged much research in an effort to provide tools to assist parallel software development. However, while these tools may cater for architecture-specific problems, they do little for the concept of parallel software engineering, as the end product is usually neither scaleable nor portable. The introduction of a level of abstraction in the expression of parallel algorithms can elevate the reasoning process above architectural constraints and assist the production of more flexible code. This paper outlines an object-oriented parallel algorithm development paradigm based on a task and channel notation, and examines the utilisation of Java TM technologies in the development of a distributed Java TM virtual machine architecture on which algorithms expressed in this notation may be executed dynamically.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128744651","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905004
R. Trobec, Uros Jovanovic
Topological parameters and routing performances of regular d-neighbours topologies are analysed and discussed in this paper. Average and maximal distances between nodes are compared for hypercubes, 3D-tori, arrangement graphs and recently introduced d-meshes, an extended family of two-dimensional regular meshes of an arbitrary degree d and an isomorphic node neighbourhood. d-meshes are superior in node-to-node distances, in the expansion scalability and in the potential for a planar implementation.
{"title":"Regular d-neighbours topologies","authors":"R. Trobec, Uros Jovanovic","doi":"10.1109/EMPDP.2001.905004","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905004","url":null,"abstract":"Topological parameters and routing performances of regular d-neighbours topologies are analysed and discussed in this paper. Average and maximal distances between nodes are compared for hypercubes, 3D-tori, arrangement graphs and recently introduced d-meshes, an extended family of two-dimensional regular meshes of an arbitrary degree d and an isomorphic node neighbourhood. d-meshes are superior in node-to-node distances, in the expansion scalability and in the potential for a planar implementation.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116105888","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905054
J. Cuenca, D. Giménez, José González
Modeling the behaviour of linear algebra algorithms is very suitable for designing linear algebra software for high performance computers. This modelization would enable us to predict the execution time of the routines depending on a number of parameters. There are two groups of parameters, in the first, there are the parameters whose values can be chosen by the user: number of processors, processors grid configuration, distribution of data in the system, block size; and in the second, we have the parameters that specify the characteristics of a target architecture: arithmetic cost and start-up and word-sending cost of a communication operation. Thus, a linear algebra library could be designed in such a way that each routine takes the values of the parameters of the first group that provide the expected optimum execution time, and solves the problem. This library could, therefore be employed by a non-expert user to solve scientific or engineering problems, because the user does not need to determine the values of these parameters. The design methodology is analysed with one-sided block Jacobi methods to solve the symmetric eigenvalue problem. Variants for a logical ring and a logical rectangular mesh of processors are considered. An analytical model of the algorithm is developed, and the behaviour of the algorithm is analysed with message-passing using MPI in a SGI Origin 2000. With the parameters chosen by our model, the execution time is reduced from about 50% higher than the optimal to just 2%.
{"title":"Modeling the behaviour of linear algebra algorithms with message-passing","authors":"J. Cuenca, D. Giménez, José González","doi":"10.1109/EMPDP.2001.905054","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905054","url":null,"abstract":"Modeling the behaviour of linear algebra algorithms is very suitable for designing linear algebra software for high performance computers. This modelization would enable us to predict the execution time of the routines depending on a number of parameters. There are two groups of parameters, in the first, there are the parameters whose values can be chosen by the user: number of processors, processors grid configuration, distribution of data in the system, block size; and in the second, we have the parameters that specify the characteristics of a target architecture: arithmetic cost and start-up and word-sending cost of a communication operation. Thus, a linear algebra library could be designed in such a way that each routine takes the values of the parameters of the first group that provide the expected optimum execution time, and solves the problem. This library could, therefore be employed by a non-expert user to solve scientific or engineering problems, because the user does not need to determine the values of these parameters. The design methodology is analysed with one-sided block Jacobi methods to solve the symmetric eigenvalue problem. Variants for a logical ring and a logical rectangular mesh of processors are considered. An analytical model of the algorithm is developed, and the behaviour of the algorithm is analysed with message-passing using MPI in a SGI Origin 2000. With the parameters chosen by our model, the execution time is reduced from about 50% higher than the optimal to just 2%.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116772614","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905040
V. Getov, M. Williams, Quanming Lu, M. Thomas
The development of Java has seen increasing attention as the most popular platform for distributed computing. However, despite Java's advantages in the area of portability and rapid prototyping, its efficiency is unavoidably compromised through its commitment to portability. In this paper we present performance analysis and comparisons of evaluation results for both Java and C/Fortran on three different message-passing parallel platforms-a shared memory multi-processor (Sun E4000), a Linux cluster, and a distributed memory computer (IBM SP-2). The NAS Embarrassingly Parallel and Integer Sort benchmarks were selected for this evaluation. Both the original Fortran/C codes and Java versions of these two kernels were used for obtaining the performance measurements as part of our project. The evaluation results demonstrate the feasibility of message-passing computing with Java on a wide range of computer platforms. Depending on the system and the software components installed, significant impact on the message-passing performance will have the efficiency of the native MPI library and the version of the Java platform.
{"title":"Message-passing computing with Java: performance evaluation and comparisons","authors":"V. Getov, M. Williams, Quanming Lu, M. Thomas","doi":"10.1109/EMPDP.2001.905040","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905040","url":null,"abstract":"The development of Java has seen increasing attention as the most popular platform for distributed computing. However, despite Java's advantages in the area of portability and rapid prototyping, its efficiency is unavoidably compromised through its commitment to portability. In this paper we present performance analysis and comparisons of evaluation results for both Java and C/Fortran on three different message-passing parallel platforms-a shared memory multi-processor (Sun E4000), a Linux cluster, and a distributed memory computer (IBM SP-2). The NAS Embarrassingly Parallel and Integer Sort benchmarks were selected for this evaluation. Both the original Fortran/C codes and Java versions of these two kernels were used for obtaining the performance measurements as part of our project. The evaluation results demonstrate the feasibility of message-passing computing with Java on a wide range of computer platforms. Depending on the system and the software components installed, significant impact on the message-passing performance will have the efficiency of the native MPI library and the version of the Java platform.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130442282","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905042
E. Mehofer, Bernhard Scholz
In high-performance systems execution time is of crucial importance justifying advanced optimization techniques. Traditionally, optimization is based on static program analysis. The quality of program optimizations, however, can be substantially improved by utilizing runtime information. Probabilistic data-flow frameworks compute the probability with what data-flow facts may hold at some program point based on representative profile runs. Advanced optimizations can use this information in order to produce highly efficient code. In this paper we introduce a novel optimization technique in the context of High Performance Fortran (HPF) that is based on probabilistic data-flow information. We consider statically undefined attributes which play an important role for parallelization and compute for those attributes the probabilities to hold some specific value during runtime. For the most probable attribute values highly-optimized, specialized code is generated. In this way significantly better performance results can be achieved. The implementation of our optimization is done in the context of VFC, a source-to-source parallelizing compiler for HPF/F90.
{"title":"Probabilistic communication optimizations and parallelization for distributed-memory systems","authors":"E. Mehofer, Bernhard Scholz","doi":"10.1109/EMPDP.2001.905042","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905042","url":null,"abstract":"In high-performance systems execution time is of crucial importance justifying advanced optimization techniques. Traditionally, optimization is based on static program analysis. The quality of program optimizations, however, can be substantially improved by utilizing runtime information. Probabilistic data-flow frameworks compute the probability with what data-flow facts may hold at some program point based on representative profile runs. Advanced optimizations can use this information in order to produce highly efficient code. In this paper we introduce a novel optimization technique in the context of High Performance Fortran (HPF) that is based on probabilistic data-flow information. We consider statically undefined attributes which play an important role for parallelization and compute for those attributes the probabilities to hold some specific value during runtime. For the most probable attribute values highly-optimized, specialized code is generated. In this way significantly better performance results can be achieved. The implementation of our optimization is done in the context of VFC, a source-to-source parallelizing compiler for HPF/F90.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"447 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134311973","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 : 2001-02-07DOI: 10.1109/EMPDP.2001.905078
Jörg Schulz, C. Hochberger, D. Tavangarian
This paper presents a new algorithm to predict the communication performance for high performance parallel computing in wide area networks. Such a powerful prediction allows to balance the requirements of communication time and computation time. Such a system can be used in almost any wide area computing application. The major feature of this algorithm is the consideration of the human rhythm of life. Prediction values are calculated using a selected number of arguments, depending on daytime and weekday. Thus it is possible to give very accurate prediction values several weeks ahead. In this paper we discuss the usage of this method in the hypercomputer at the University of Restock. The prediction algorithm and monitoring tools are written in Java and can thus be used on almost any platform.
{"title":"Prediction of communication performance for wide area computing systems","authors":"Jörg Schulz, C. Hochberger, D. Tavangarian","doi":"10.1109/EMPDP.2001.905078","DOIUrl":"https://doi.org/10.1109/EMPDP.2001.905078","url":null,"abstract":"This paper presents a new algorithm to predict the communication performance for high performance parallel computing in wide area networks. Such a powerful prediction allows to balance the requirements of communication time and computation time. Such a system can be used in almost any wide area computing application. The major feature of this algorithm is the consideration of the human rhythm of life. Prediction values are calculated using a selected number of arguments, depending on daytime and weekday. Thus it is possible to give very accurate prediction values several weeks ahead. In this paper we discuss the usage of this method in the hypercomputer at the University of Restock. The prediction algorithm and monitoring tools are written in Java and can thus be used on almost any platform.","PeriodicalId":262971,"journal":{"name":"Proceedings Ninth Euromicro Workshop on Parallel and Distributed Processing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130110069","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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