Pub Date : 2013-07-01DOI: 10.1109/ISCC.2013.6755015
Tian Mi, Sanguthevar Rajasekaran
Numerous OLAP queries process selection operations of "top N", median, "top 5%", in data warehousing applications. Selection is a well-studied problem that has numerous applications in the management of data and databases since, typically, any complex data query can be reduced to a series of basic operations such as sorting and selection. The parallel selection has also become an important fundamental operation, especially after parallel databases were introduced. In this paper, we present a deterministic algorithm Recursive Sampling Selection (RSS) to solve the exact out-of-core selection problem, which we show needs no more than (2 + ε) passes (ε being a very small fraction). We have compared our RSS algorithm with two other algorithms in the literature, namely, the Deterministic Sampling Selection and QuickSelect on the Parallel Disks Systems. Our analysis shows that DSS is a (2 + ε)-pass algorithm when the total number of input elements N is a polynomial in the memory size M (i.e., N = Mc for some constant c). While, our proposed algorithm RSS runs in (2 + ε) passes without any assumptions. Experimental results indicate that both RSS and DSS outperform QuickSelect on the Parallel Disks Systems. Especially, the proposed algorithm RSS is more scalable and robust to handle big data when the input size is far greater than the core memory size, including the case of N ≫ Mc .
{"title":"A Two-Pass Exact Algorithm for Selection on Parallel Disk Systems.","authors":"Tian Mi, Sanguthevar Rajasekaran","doi":"10.1109/ISCC.2013.6755015","DOIUrl":"https://doi.org/10.1109/ISCC.2013.6755015","url":null,"abstract":"<p><p>Numerous OLAP queries process selection operations of \"top N\", median, \"top 5%\", in data warehousing applications. Selection is a well-studied problem that has numerous applications in the management of data and databases since, typically, any complex data query can be reduced to a series of basic operations such as sorting and selection. The parallel selection has also become an important fundamental operation, especially after parallel databases were introduced. In this paper, we present a deterministic algorithm <i>Recursive Sampling Selection (RSS)</i> to solve the exact out-of-core selection problem, which we show needs no more than (2 + <i>ε</i>) passes (<i>ε</i> being a very small fraction). We have compared our <i>RSS</i> algorithm with two other algorithms in the literature, namely, the <i>Deterministic Sampling Selection</i> and <i>QuickSelect</i> on the Parallel Disks Systems. Our analysis shows that <i>DSS</i> is a (2 + <i>ε</i>)-pass algorithm when the total number of input elements <i>N</i> is a polynomial in the memory size <i>M</i> (i.e., <i>N</i> = <i>M<sup>c</sup></i> for some constant <i>c</i>). While, our proposed algorithm <i>RSS</i> runs in (2 + <i>ε</i>) passes without any assumptions. Experimental results indicate that both <i>RSS</i> and <i>DSS</i> outperform <i>QuickSelect</i> on the Parallel Disks Systems. Especially, the proposed algorithm <i>RSS</i> is more scalable and robust to handle big data when the input size is far greater than the core memory size, including the case of <i>N</i> ≫ <i>M<sup>c</sup></i> .</p>","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"2013 ","pages":"000612-617"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/ISCC.2013.6755015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32795374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-06-27DOI: 10.1109/SCAC.1995.523689
H. Kim
We have introduced the trellis-coded M-ary (M=32) 4-dimensional (4-D) orthogonal modulation scheme. Here, a rate 4/5 convolutional encoder generates one of 32 possible symbols every T seconds. Then the signal mapping for 32 symbols is performed by a M-ary 4-D orthogonal modulator. The M-ary 4-D modulator employs the vectors which is derived by the optimization technique of signal waveforms in a 4-D sphere. The technique is used in maximizing the minimum Euclidean distance between a set of signal points on a multidimensional sphere. After combining coding with M-ary 4-D modulation, we have obtained a considerable improvement in the free minimum distance of the system. The new system achieves asymptotic coding gains up to 6.4 dB over the uncoded two-independent QPSK scheme and 3.4 dB over the two-independent 2-D TCM scheme.
{"title":"Trellis-coded M-ary orthogonal modulation","authors":"H. Kim","doi":"10.1109/SCAC.1995.523689","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523689","url":null,"abstract":"We have introduced the trellis-coded M-ary (M=32) 4-dimensional (4-D) orthogonal modulation scheme. Here, a rate 4/5 convolutional encoder generates one of 32 possible symbols every T seconds. Then the signal mapping for 32 symbols is performed by a M-ary 4-D orthogonal modulator. The M-ary 4-D modulator employs the vectors which is derived by the optimization technique of signal waveforms in a 4-D sphere. The technique is used in maximizing the minimum Euclidean distance between a set of signal points on a multidimensional sphere. After combining coding with M-ary 4-D modulation, we have obtained a considerable improvement in the free minimum distance of the system. The new system achieves asymptotic coding gains up to 6.4 dB over the uncoded two-independent QPSK scheme and 3.4 dB over the two-independent 2-D TCM scheme.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"37 1","pages":"364-367"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85616962","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523646
C. Kroll
The rapid increase of communication networks complexity force to the need of a common information pool for network operation, administration and management. Siemens Austria developed a network management information system in cooperation and under supervision of ESA. The resulting system based on object oriented techniques provides a powerful tool for network control and coordination in every day use. This paper focuses on the design and implementation process of the project.
{"title":"Object oriented network operation, administration and management","authors":"C. Kroll","doi":"10.1109/SCAC.1995.523646","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523646","url":null,"abstract":"The rapid increase of communication networks complexity force to the need of a common information pool for network operation, administration and management. Siemens Austria developed a network management information system in cooperation and under supervision of ESA. The resulting system based on object oriented techniques provides a powerful tool for network control and coordination in every day use. This paper focuses on the design and implementation process of the project.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"280 1","pages":"50-56"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77131845","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523663
C. Fuhrman, S. Chutani, H. Nussbaumer
N-modular redundancy (NMR) and N-version programming (NVP) are two popular fault tolerance techniques in which hardware and software redundancy is exploited to mask faults. Redundant hardware is used to improve fault tolerance rather than throughput. We introduce a scheme for combined hardware-software fault tolerance derived from NMR and NVP that shows how redundancy can also be used to improve throughput by grouping the execution of several tasks. Our scheme uses a dynamic task allocation algorithm with an optimistic execution policy where the number of task executions is kept close to the minimum required to produce fault-free results. For equivalent hardware and software resources, the proposed method is 50% to 100% more efficient in terms of throughput and latency.
{"title":"Hardware/software fault tolerance with multiple task modular redundancy","authors":"C. Fuhrman, S. Chutani, H. Nussbaumer","doi":"10.1109/SCAC.1995.523663","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523663","url":null,"abstract":"N-modular redundancy (NMR) and N-version programming (NVP) are two popular fault tolerance techniques in which hardware and software redundancy is exploited to mask faults. Redundant hardware is used to improve fault tolerance rather than throughput. We introduce a scheme for combined hardware-software fault tolerance derived from NMR and NVP that shows how redundancy can also be used to improve throughput by grouping the execution of several tasks. Our scheme uses a dynamic task allocation algorithm with an optimistic execution policy where the number of task executions is kept close to the minimum required to produce fault-free results. For equivalent hardware and software resources, the proposed method is 50% to 100% more efficient in terms of throughput and latency.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"61 1","pages":"171-177"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91282516","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523678
H. Sueyllam, M. A. Ismail, K. M. Ahmed
Separable algorithms are useful in casting image warping into a framework that is amenable to hardware implementation. Growing interest in this area has gained impetus from the widespread proliferation of advanced workstations and digital signal processors. Examples include realtime hardware for video effects among others. The central benefit of separable algorithms is the reduction in complexity of one dimensional resampling algorithms. When the input is restricted to be one-dimensional, efficient solutions are made possible for the image reconstruction and antialiasing components of resampling. Fant (1986) presented such a solution that is well suited for hardware implementation. Fant's algorithm, however, is inherently serial. We present an alternative but equivalent (in the sense of producing exactly the same output scan lines) algorithm, that is parallel. The new algorithm was inspired by Wolberg's algorithm (1990). The new algorithm adds some overhead to the hardware implementation of Fant's algorithm to be able to achieve parallelism.
{"title":"A parallel one dimensional resampling algorithm","authors":"H. Sueyllam, M. A. Ismail, K. M. Ahmed","doi":"10.1109/SCAC.1995.523678","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523678","url":null,"abstract":"Separable algorithms are useful in casting image warping into a framework that is amenable to hardware implementation. Growing interest in this area has gained impetus from the widespread proliferation of advanced workstations and digital signal processors. Examples include realtime hardware for video effects among others. The central benefit of separable algorithms is the reduction in complexity of one dimensional resampling algorithms. When the input is restricted to be one-dimensional, efficient solutions are made possible for the image reconstruction and antialiasing components of resampling. Fant (1986) presented such a solution that is well suited for hardware implementation. Fant's algorithm, however, is inherently serial. We present an alternative but equivalent (in the sense of producing exactly the same output scan lines) algorithm, that is parallel. The new algorithm was inspired by Wolberg's algorithm (1990). The new algorithm adds some overhead to the hardware implementation of Fant's algorithm to be able to achieve parallelism.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"133 1","pages":"277-281"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76114872","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523656
E. S. Tollar, J. M. Bennett
Standard measures do not adequately reflect the importance of the very large and significant outages that can now occur in the modern telecommunications networks. The impact measure developed originally at Bellcore that is the basis for the new T1A1 measure of network performance is described. We assumed a useful impact measure must: (a) appropriately order a set of outages by the severity of the outages, and (b) allow for meaningful comparisons of network performance on a yearly or quarterly basis. Comparisons of the new impact measure to some standard measures of reliability illustrate that the new measure provides a significant improvement in the ability to assess the severity of individual outages, and the performance of the network over a given time period. Also provided are examples consistent with network performance which illustrate that the new impact measure is more consistent with the actual assessment of the network performance than other proposed measures of reliability.
{"title":"Network outage impact measures for telecommunications","authors":"E. S. Tollar, J. M. Bennett","doi":"10.1109/SCAC.1995.523656","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523656","url":null,"abstract":"Standard measures do not adequately reflect the importance of the very large and significant outages that can now occur in the modern telecommunications networks. The impact measure developed originally at Bellcore that is the basis for the new T1A1 measure of network performance is described. We assumed a useful impact measure must: (a) appropriately order a set of outages by the severity of the outages, and (b) allow for meaningful comparisons of network performance on a yearly or quarterly basis. Comparisons of the new impact measure to some standard measures of reliability illustrate that the new measure provides a significant improvement in the ability to assess the severity of individual outages, and the performance of the network over a given time period. Also provided are examples consistent with network performance which illustrate that the new impact measure is more consistent with the actual assessment of the network performance than other proposed measures of reliability.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"41 1","pages":"120-126"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/SCAC.1995.523656","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72517811","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523671
Y. Sekercioglu, A. Pitsillides
High-speed LANs are beginning to migrate from shared media to switch based configurations (commonly based on ATM architectures). Because of the characteristics of ATM networks and nature of LAN traffic, there is a need for effective congestion control strategies to be developed in order to maintain the network utilization and throughput at optimum levels. We describe and report the simulation results of a novel congestion control strategy based on the principles of fuzzy logic control for the management of ABR traffic in ATM LANs. We propose that fuzzy logic control is an effective scheme for designing congestion control mechanisms in ATM LANs. Our simulations show that, proposed fuzzy backward congestion notification (FBCN) method is effective in minimizing cell losses at the switch queues and prevents time consuming packet retransmissions which can dramatically degrade the network throughput.
{"title":"Fuzzy control of ABR traffic flow in ATM LANs","authors":"Y. Sekercioglu, A. Pitsillides","doi":"10.1109/SCAC.1995.523671","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523671","url":null,"abstract":"High-speed LANs are beginning to migrate from shared media to switch based configurations (commonly based on ATM architectures). Because of the characteristics of ATM networks and nature of LAN traffic, there is a need for effective congestion control strategies to be developed in order to maintain the network utilization and throughput at optimum levels. We describe and report the simulation results of a novel congestion control strategy based on the principles of fuzzy logic control for the management of ABR traffic in ATM LANs. We propose that fuzzy logic control is an effective scheme for designing congestion control mechanisms in ATM LANs. Our simulations show that, proposed fuzzy backward congestion notification (FBCN) method is effective in minimizing cell losses at the switch queues and prevents time consuming packet retransmissions which can dramatically degrade the network throughput.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"99 1","pages":"227-232"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79489369","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523642
E. Chan, J. M. Ng, V. Lee, M. Chan, Chan-Hee Lee
The use of ATM networks in interconnecting LANs and MANs results in a bandwidth allocation problem due to the connectionless nature of most LAN/MAN traffic. A well known scheme is to use bandwidth advertising in which available bandwidth is broadcast to allow for users contention. This paper presents an enhancement over the basic scheme that will improve the burst loss rate significantly at high network loads.
{"title":"Bandwidth allocation for interconnecting LAN/MANs and ATM networks","authors":"E. Chan, J. M. Ng, V. Lee, M. Chan, Chan-Hee Lee","doi":"10.1109/SCAC.1995.523642","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523642","url":null,"abstract":"The use of ATM networks in interconnecting LANs and MANs results in a bandwidth allocation problem due to the connectionless nature of most LAN/MAN traffic. A well known scheme is to use bandwidth advertising in which available bandwidth is broadcast to allow for users contention. This paper presents an enhancement over the basic scheme that will improve the burst loss rate significantly at high network loads.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"28 1","pages":"23-28"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89529719","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523647
T. Apostolopoulos, V. C. Daskalou
This paper presents a prototype for management services which enables the performance monitoring and control of resources in a TCP/IP network. A time reference information model required to accomplish the different needs of performance management functions, is also described. This temporal model can be used not only to provide a diachronic view of the management information, but also to define a set of measures needed to observe the performance of network elements. The performance management application is implemented using a distributed architecture. It provides facilities to dynamically create aggregate managed objects, to collect the management information and to store the collected data in a database. The database schema is designed to follow the proposed time reference information model and also the structure of the MIB. Finally, the architecture of the prototype and the supported facilities are also illustrated in this paper.
{"title":"On the implementation of a prototype for performance management services","authors":"T. Apostolopoulos, V. C. Daskalou","doi":"10.1109/SCAC.1995.523647","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523647","url":null,"abstract":"This paper presents a prototype for management services which enables the performance monitoring and control of resources in a TCP/IP network. A time reference information model required to accomplish the different needs of performance management functions, is also described. This temporal model can be used not only to provide a diachronic view of the management information, but also to define a set of measures needed to observe the performance of network elements. The performance management application is implemented using a distributed architecture. It provides facilities to dynamically create aggregate managed objects, to collect the management information and to store the collected data in a database. The database schema is designed to follow the proposed time reference information model and also the structure of the MIB. Finally, the architecture of the prototype and the supported facilities are also illustrated in this paper.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"10 1","pages":"57-63"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89590772","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 : 1995-06-27DOI: 10.1109/SCAC.1995.523669
M. Hamdi, Lixin Wang
Multimedia services, teleconferencing, high performance visualization, and distributed supercomputing are expected to accelerate the demand for high-speed local and metropolitan area networks (LAN/MANs). In this paper, we propose a new MAC protocol, called fast reservation multiple access (FRMA), which is suitable for a folded bus high-speed MANs and LANs. Its main feature is a sample and fast reservation technique that allow stations to reserve transmission slots. The goal of the reservation is to maximize the throughput of the system and to ensure fairness among the attached stations. A complete description of the FRMA protocol and the associated nodes are given. Then, we show the performance of FRMA as a function of its throughput, mean delays, and fairness using simulation results. Our protocol is shown to achieve high throughput and small transmission delays while preserving the fairness of the whole network. Thus, the FRMA protocol seem to be an appropriate choice for future generation high-speed MANs and LANs.
{"title":"FRMA: a new high-speed metropolitan and local area network protocol","authors":"M. Hamdi, Lixin Wang","doi":"10.1109/SCAC.1995.523669","DOIUrl":"https://doi.org/10.1109/SCAC.1995.523669","url":null,"abstract":"Multimedia services, teleconferencing, high performance visualization, and distributed supercomputing are expected to accelerate the demand for high-speed local and metropolitan area networks (LAN/MANs). In this paper, we propose a new MAC protocol, called fast reservation multiple access (FRMA), which is suitable for a folded bus high-speed MANs and LANs. Its main feature is a sample and fast reservation technique that allow stations to reserve transmission slots. The goal of the reservation is to maximize the throughput of the system and to ensure fairness among the attached stations. A complete description of the FRMA protocol and the associated nodes are given. Then, we show the performance of FRMA as a function of its throughput, mean delays, and fairness using simulation results. Our protocol is shown to achieve high throughput and small transmission delays while preserving the fairness of the whole network. Thus, the FRMA protocol seem to be an appropriate choice for future generation high-speed MANs and LANs.","PeriodicalId":90699,"journal":{"name":"Proceedings. IEEE Symposium on Computers and Communications","volume":"33 1","pages":"213-219"},"PeriodicalIF":0.0,"publicationDate":"1995-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89822756","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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