Pub Date : 1997-08-05DOI: 10.1109/HPDC.1997.626400
A. Asthana, J. Sienicki, M. Srivastava
Kaleido is a system for flexible concurrent processing of multimedia flows where applications are decomposed into building blocks called "active buffers" whose computation and I/O requirements are characterized so as to allow reservation of CPU and bandwidth resources. The input and output ports of active buffers in a Kaleido application are connected by channels. The active buffers in an application may themselves be mapped either to a single compute node, or to multiple compute nodes connected by a network. The Kaleido runtime system software transparently handles the resulting local and remote channels by providing the abstraction of a distributed "active backplane". This "active backplane" also allows dynamic applications whose functional partitioning among compute nodes can be adapted to network, server, and terminal resources. The paper also describes I/O-centric hardware extensions that we have developed for efficient handling of concurrent multimedia streams in Kaleido.
{"title":"Kaleido: an environment for composing networked multimedia applications","authors":"A. Asthana, J. Sienicki, M. Srivastava","doi":"10.1109/HPDC.1997.626400","DOIUrl":"https://doi.org/10.1109/HPDC.1997.626400","url":null,"abstract":"Kaleido is a system for flexible concurrent processing of multimedia flows where applications are decomposed into building blocks called \"active buffers\" whose computation and I/O requirements are characterized so as to allow reservation of CPU and bandwidth resources. The input and output ports of active buffers in a Kaleido application are connected by channels. The active buffers in an application may themselves be mapped either to a single compute node, or to multiple compute nodes connected by a network. The Kaleido runtime system software transparently handles the resulting local and remote channels by providing the abstraction of a distributed \"active backplane\". This \"active backplane\" also allows dynamic applications whose functional partitioning among compute nodes can be adapted to network, server, and terminal resources. The paper also describes I/O-centric hardware extensions that we have developed for efficient handling of concurrent multimedia streams in Kaleido.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121749960","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 : 1997-08-05DOI: 10.1109/HPDC.1997.626436
D. A. Evensky, A. Gentile, L. Camp, R. Armstrong
Lilith is a general purpose tool to provide highly scalable, easy distribution of user code across a heterogeneous computing platform. Lilith's principal task is to span a heterogeneous tree of machines executing user-defined code in a scalable and secure fashion. Lilith will be used for controlling user processes as well as general system administrative tasks. Lilith is written in Java, taking advantage of Java's platform independence and intent to move code across networks. The design of Lilith provides hooks for experimenting with tree-spanning algorithms and security schemes. We present the Lilith Object model, security scheme, and implementation, and present timing results demonstrating Lilith's scalable behavior.
{"title":"Lilith: Scalable execution of user code for distributed computing","authors":"D. A. Evensky, A. Gentile, L. Camp, R. Armstrong","doi":"10.1109/HPDC.1997.626436","DOIUrl":"https://doi.org/10.1109/HPDC.1997.626436","url":null,"abstract":"Lilith is a general purpose tool to provide highly scalable, easy distribution of user code across a heterogeneous computing platform. Lilith's principal task is to span a heterogeneous tree of machines executing user-defined code in a scalable and secure fashion. Lilith will be used for controlling user processes as well as general system administrative tasks. Lilith is written in Java, taking advantage of Java's platform independence and intent to move code across networks. The design of Lilith provides hooks for experimenting with tree-spanning algorithms and security schemes. We present the Lilith Object model, security scheme, and implementation, and present timing results demonstrating Lilith's scalable behavior.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121099372","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 : 1997-08-05DOI: 10.1109/HPDC.1997.626445
Steven M. Fitzgerald, Ian T Foster, C. Kesselman, G. Laszewski, Warren Smith, S. Tuecke
High-performance execution in distributed computing environments often requires careful selection and configuration not only of computers, networks, and other resources but also of the protocols and algorithms used by applications. Selection and configuration in turn require access to accurate, up-to-date information on the structure and state of available resources. Unfortunately no standard mechanism exists for organizing or accessing such information. Consequently different tools and applications adopt ad hoc mechanisms, or they compromise their portability and performance by using default configurations. We propose a Metacomputing Directory Service that provides efficient and scalable access to diverse, dynamic, and distributed information about resource structure and state. We define an extensible data model to represent required information and present a scalable, high-performance, distributed implementation. The data representation and application programming interface are adopted from the Lightweight Directory Access Protocol; the data model and implementation are new. We use the Globus distributed computing toolkit to illustrate how this directory service enables the development of more flexible and efficient distributed computing services and applications.
{"title":"A directory service for configuring high-performance distributed computations","authors":"Steven M. Fitzgerald, Ian T Foster, C. Kesselman, G. Laszewski, Warren Smith, S. Tuecke","doi":"10.1109/HPDC.1997.626445","DOIUrl":"https://doi.org/10.1109/HPDC.1997.626445","url":null,"abstract":"High-performance execution in distributed computing environments often requires careful selection and configuration not only of computers, networks, and other resources but also of the protocols and algorithms used by applications. Selection and configuration in turn require access to accurate, up-to-date information on the structure and state of available resources. Unfortunately no standard mechanism exists for organizing or accessing such information. Consequently different tools and applications adopt ad hoc mechanisms, or they compromise their portability and performance by using default configurations. We propose a Metacomputing Directory Service that provides efficient and scalable access to diverse, dynamic, and distributed information about resource structure and state. We define an extensible data model to represent required information and present a scalable, high-performance, distributed implementation. The data representation and application programming interface are adopted from the Lightweight Directory Access Protocol; the data model and implementation are new. We use the Globus distributed computing toolkit to illustrate how this directory service enables the development of more flexible and efficient distributed computing services and applications.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132702721","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 : 1997-08-05DOI: 10.1109/HPDC.1997.626686
Mark Hayden, R. V. Renesse
Layering of communication protocols offers many well-known advantages but typically leads to performance inefficiencies. We present a model for layering, and point out where the performance problems occur in stacks of layers using this model. We then investigate the common execution paths in these stacks and how to identify them. These paths are optimized using three techniques: optimizing the computation, compressing protocol headers, and delaying processing. All of the optimizations can be automated in a compiler with the help of minor annotations by the protocol designer. We describe the performance that we obtain after implementing the optimizations by hand on a full-scale system.
{"title":"Optimizing layered communication protocols","authors":"Mark Hayden, R. V. Renesse","doi":"10.1109/HPDC.1997.626686","DOIUrl":"https://doi.org/10.1109/HPDC.1997.626686","url":null,"abstract":"Layering of communication protocols offers many well-known advantages but typically leads to performance inefficiencies. We present a model for layering, and point out where the performance problems occur in stacks of layers using this model. We then investigate the common execution paths in these stacks and how to identify them. These paths are optimized using three techniques: optimizing the computation, compressing protocol headers, and delaying processing. All of the optimizations can be automated in a compiler with the help of minor annotations by the protocol designer. We describe the performance that we obtain after implementing the optimizations by hand on a full-scale system.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126620630","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 : 1997-08-05DOI: 10.1109/HPDC.1997.622360
K. Keahey, Dennis Gannon
This paper describes PARDIS, a system containing explicit support for interoperability of PARallel DIStributed applications. PARDIS is based on the Common Object Request Broker Architecture (CORBA). Like CORBA, it provides interoperability between heterogeneous components by specifying their interfaces in a meta-language, the CORBA IDL, which call be translated into the language of interacting components. However, PARDIS extends the CORBA object model by introducing SPMD objects representing data-parallel computations. SPMD objects allow the request broker to interact directly with the distributed resources of a parallel application. This capability ensures request delivery to all the computing threads of a parallel application and allows the request broker to transfer distributed arguments directly between the computing threads of the client and the server. To support this kind of argument transfer, PARDIS defines a distributed argument type-distributed sequence-a generalization of CORBA sequence representing distributed data structures of parallel applications. In this paper we will give a brief description of basic component interaction in PARDIS and give an account of the rationale and support for SPMD objects and distributed sequences. We will then describe two ways of implementing argument transfer in invocations on SPMD objects and evaluate and compare their performance.
{"title":"PARDIS: A parallel approach to CORBA","authors":"K. Keahey, Dennis Gannon","doi":"10.1109/HPDC.1997.622360","DOIUrl":"https://doi.org/10.1109/HPDC.1997.622360","url":null,"abstract":"This paper describes PARDIS, a system containing explicit support for interoperability of PARallel DIStributed applications. PARDIS is based on the Common Object Request Broker Architecture (CORBA). Like CORBA, it provides interoperability between heterogeneous components by specifying their interfaces in a meta-language, the CORBA IDL, which call be translated into the language of interacting components. However, PARDIS extends the CORBA object model by introducing SPMD objects representing data-parallel computations. SPMD objects allow the request broker to interact directly with the distributed resources of a parallel application. This capability ensures request delivery to all the computing threads of a parallel application and allows the request broker to transfer distributed arguments directly between the computing threads of the client and the server. To support this kind of argument transfer, PARDIS defines a distributed argument type-distributed sequence-a generalization of CORBA sequence representing distributed data structures of parallel applications. In this paper we will give a brief description of basic component interaction in PARDIS and give an account of the rationale and support for SPMD objects and distributed sequences. We will then describe two ways of implementing argument transfer in invocations on SPMD objects and evaluate and compare their performance.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126345087","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 : 1997-08-05DOI: 10.1109/HPDC.1997.622363
S. Singhal, B. Q. Nguyen, R. Redpath, Jimmy Nguyen, Michael Fraenkel
Faster networks, faster processors, and standardized protocols have enabled the emergence of interactive applications running over commercial networks such as the Internet. In such applications, multiple users interact with one another by exchanging real-time information such as user position and orientation in a virtual world, live and recorded audio, video, and text. These applications include interactive shopping, team training, virtual meeting rooms, and multi-player games. However, to date, these interactive systems have supported a limited number of information types, offered limited scalability, and have failed to account for a heterogeneous network and processor environment. In this paper, we describe the design and implementation of InVerse, an infrastructure that supports real-time interactive applications on the Internet. InVerse provides a common backplane for disseminating and managing multiple real-time data streams. Within this general-purpose structure, the InVerse system maximizes scalability by implementing a hybrid communications architecture that adapts itself to available network bandwidth, observed network latency, installed network security measures, and available services such as multicast.
{"title":"InVerse: Designing an interactive universe architecture for scalability and extensibility","authors":"S. Singhal, B. Q. Nguyen, R. Redpath, Jimmy Nguyen, Michael Fraenkel","doi":"10.1109/HPDC.1997.622363","DOIUrl":"https://doi.org/10.1109/HPDC.1997.622363","url":null,"abstract":"Faster networks, faster processors, and standardized protocols have enabled the emergence of interactive applications running over commercial networks such as the Internet. In such applications, multiple users interact with one another by exchanging real-time information such as user position and orientation in a virtual world, live and recorded audio, video, and text. These applications include interactive shopping, team training, virtual meeting rooms, and multi-player games. However, to date, these interactive systems have supported a limited number of information types, offered limited scalability, and have failed to account for a heterogeneous network and processor environment. In this paper, we describe the design and implementation of InVerse, an infrastructure that supports real-time interactive applications on the Internet. InVerse provides a common backplane for disseminating and managing multiple real-time data streams. Within this general-purpose structure, the InVerse system maximizes scalability by implementing a hybrid communications architecture that adapts itself to available network bandwidth, observed network latency, installed network security measures, and available services such as multicast.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130697714","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 : 1997-08-05DOI: 10.1109/HPDC.1997.622362
R. Armstrong, P. Wyckoff, C. Yam, M. Bui-Pham, Nancy Brown
Algorithms for generalized particle methods are discussed in the context of high-performance parallel distributed computing. An object-oriented framework for such methods is presented along with the implementation of several very different scientific particle-based applications using the POET framework.
{"title":"Frame-based components for generalized particle methods","authors":"R. Armstrong, P. Wyckoff, C. Yam, M. Bui-Pham, Nancy Brown","doi":"10.1109/HPDC.1997.622362","DOIUrl":"https://doi.org/10.1109/HPDC.1997.622362","url":null,"abstract":"Algorithms for generalized particle methods are discussed in the context of high-performance parallel distributed computing. An object-oriented framework for such methods is presented along with the implementation of several very different scientific particle-based applications using the POET framework.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116012623","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 : 1997-08-05DOI: 10.1109/HPDC.1997.622365
R. Simon, A. Sood
An important class of multimedia applications involve real-time distributed collaboration or distributed control. This paper examines some of the issues in network support for this class of applications and presents Collaborative Load-Balanced Routing (CLBR), a new technique for routing and call establishment of distributed collaborative and control multimedia applications. CLBR substantially reduces the overhead of communication establishment in the network between two-party distributed multimedia applications. This is achieved through an adaptive load-balancing and single source single pass approach to routing and call establishment. A large scale simulation study comparing CLBR to other types of uni-cast routing shows that this speed up can be achieved without any corresponding decrease in the networks ability to support new communication requests.
{"title":"Load-balanced routing for collaborative multimedia communication","authors":"R. Simon, A. Sood","doi":"10.1109/HPDC.1997.622365","DOIUrl":"https://doi.org/10.1109/HPDC.1997.622365","url":null,"abstract":"An important class of multimedia applications involve real-time distributed collaboration or distributed control. This paper examines some of the issues in network support for this class of applications and presents Collaborative Load-Balanced Routing (CLBR), a new technique for routing and call establishment of distributed collaborative and control multimedia applications. CLBR substantially reduces the overhead of communication establishment in the network between two-party distributed multimedia applications. This is achieved through an adaptive load-balancing and single source single pass approach to routing and call establishment. A large scale simulation study comparing CLBR to other types of uni-cast routing shows that this speed up can be achieved without any corresponding decrease in the networks ability to support new communication requests.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127313132","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 : 1997-08-05DOI: 10.1109/HPDC.1997.622364
T. Disz, I. Judson, R. Olson, R. Stevens
With the growing presence of multimedia-enabled systems, we will see an integration of collaborative computing concepts into future scientific and technical workplaces. Desktop teleconferencing is common today, while more complex teleconferencing technology that relies on the availability of multipoint-enabled tools is starting to become available on PCs. A critical problem when using these collaborative tools is archiving multistream, multipoint meetings and making the content available to others. Ideally, one would like the ability to capture, record, play back, index, annotate, and distribute multimedia stream data as easily as we currently handle text or still-image data. The Argonne Voyager project is exploring and developing media server technology needed to provide such a flexible, virtual multipoint recording/playback capability. In this article we describe the motivating requirements, architecture, implementation, operation, performance, and related work.
{"title":"The Argonne Voyager multimedia server","authors":"T. Disz, I. Judson, R. Olson, R. Stevens","doi":"10.1109/HPDC.1997.622364","DOIUrl":"https://doi.org/10.1109/HPDC.1997.622364","url":null,"abstract":"With the growing presence of multimedia-enabled systems, we will see an integration of collaborative computing concepts into future scientific and technical workplaces. Desktop teleconferencing is common today, while more complex teleconferencing technology that relies on the availability of multipoint-enabled tools is starting to become available on PCs. A critical problem when using these collaborative tools is archiving multistream, multipoint meetings and making the content available to others. Ideally, one would like the ability to capture, record, play back, index, annotate, and distribute multimedia stream data as easily as we currently handle text or still-image data. The Argonne Voyager project is exploring and developing media server technology needed to provide such a flexible, virtual multipoint recording/playback capability. In this article we describe the motivating requirements, architecture, implementation, operation, performance, and related work.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116940702","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 : 1997-08-05DOI: 10.1109/HPDC.1997.626687
Charles McMillan
In discussions of ASCI, the high-profile procurements of large computers frequently figure prominently. However, from the outset of the ASCI program, applications have been recognized as the driver. These applications feature complex, multi-physics simulations of natural phenomena that generate massive data sets as output. As we have moved from computing systems dominated by parallel vector processing to massively parallel processing we have designed new applications from the ground up to take advantage of the new capabilities. Early payoffs from this effort include running problems that are one to two orders of magnitude larger than any we have been able to run in the past. With these larger problems, we are begining the computational exploration of domains in physics, chemistry and engineering that were previously closed. As we write these codes, issues associated with languages, debuggers and visualization tools have quickly risen to the surface. The process of running large problems has strained the computational infrastructure almost to the breaking point but indicates the direction for future work.
{"title":"ASCI applications","authors":"Charles McMillan","doi":"10.1109/HPDC.1997.626687","DOIUrl":"https://doi.org/10.1109/HPDC.1997.626687","url":null,"abstract":"In discussions of ASCI, the high-profile procurements of large computers frequently figure prominently. However, from the outset of the ASCI program, applications have been recognized as the driver. These applications feature complex, multi-physics simulations of natural phenomena that generate massive data sets as output. As we have moved from computing systems dominated by parallel vector processing to massively parallel processing we have designed new applications from the ground up to take advantage of the new capabilities. Early payoffs from this effort include running problems that are one to two orders of magnitude larger than any we have been able to run in the past. With these larger problems, we are begining the computational exploration of domains in physics, chemistry and engineering that were previously closed. As we write these codes, issues associated with languages, debuggers and visualization tools have quickly risen to the surface. The process of running large problems has strained the computational infrastructure almost to the breaking point but indicates the direction for future work.","PeriodicalId":243171,"journal":{"name":"Proceedings. The Sixth IEEE International Symposium on High Performance Distributed Computing (Cat. No.97TB100183)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132015181","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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