Pub Date : 1999-05-02DOI: 10.1109/ISORC.1999.776381
R. Schantz, J. Zinky, D. Karr, D. Bakken, James Megquier, J. Loyall
As networks and the use of communications within applications continue to grow and find more uses, so too does the demand for more control and manageability of various "system properties" through middleware. An important component supporting an integrated property architecture is the concept of an object gateway, which is a quality-of-service (QoS)-aware element transparently inserted at the transport layer between clients and objects to provide managed communication behavior for the particular property being supported. In this paper, we introduce the concept of a QoS-oriented gateway to integrate a variety of QoS enforcement and implementation mechanisms controlling the underlying distributed interactions. We discuss the functions performed by such a component in achieving the desired overall end-to-end QoS, and the design considerations underlying our current implementation. We conclude with experiences to date with two variations of the gateway: one controlling managed latency and throughput using bandwidth allocation, and one controlling dependability through the coordination of object replicas.
{"title":"An object-level gateway supporting integrated-property quality of service","authors":"R. Schantz, J. Zinky, D. Karr, D. Bakken, James Megquier, J. Loyall","doi":"10.1109/ISORC.1999.776381","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776381","url":null,"abstract":"As networks and the use of communications within applications continue to grow and find more uses, so too does the demand for more control and manageability of various \"system properties\" through middleware. An important component supporting an integrated property architecture is the concept of an object gateway, which is a quality-of-service (QoS)-aware element transparently inserted at the transport layer between clients and objects to provide managed communication behavior for the particular property being supported. In this paper, we introduce the concept of a QoS-oriented gateway to integrate a variety of QoS enforcement and implementation mechanisms controlling the underlying distributed interactions. We discuss the functions performed by such a component in achieving the desired overall end-to-end QoS, and the design considerations underlying our current implementation. We conclude with experiences to date with two variations of the gateway: one controlling managed latency and throughput using bandwidth allocation, and one controlling dependability through the coordination of object replicas.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124142217","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776378
S. Chatterjee, B. Sabata, Michael Brown
Describes SRI International's ERDoS (End-to-end Resource management of Distributed Systems) project. ERDoS is a distributed middleware with comprehensive resource management support, including application scheduling, resource allocation and graceful adaptation. We discuss how we have implemented this resource management as part of the Java Virtual Machine (JVM). We have also provided a resource management application programming interface (API) as a new Java class library. The ERDoS development environment enables nonprogrammers to create complex distributed applications by simply stringing together multiple Java methods. The ERDoS runtime environment utilizes a structuring algorithm to create a distributed Java application dynamically, and then provides allocation, scheduling and content-based, graceful, adaptive QoS support to these applications. We demonstrate the benefits of content-based adaptation and of dynamic structuring of distributed applications, using a set of video applications.
{"title":"Adaptive QoS support for distributed, Java-based applications","authors":"S. Chatterjee, B. Sabata, Michael Brown","doi":"10.1109/ISORC.1999.776378","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776378","url":null,"abstract":"Describes SRI International's ERDoS (End-to-end Resource management of Distributed Systems) project. ERDoS is a distributed middleware with comprehensive resource management support, including application scheduling, resource allocation and graceful adaptation. We discuss how we have implemented this resource management as part of the Java Virtual Machine (JVM). We have also provided a resource management application programming interface (API) as a new Java class library. The ERDoS development environment enables nonprogrammers to create complex distributed applications by simply stringing together multiple Java methods. The ERDoS runtime environment utilizes a structuring algorithm to create a distributed Java application dynamically, and then provides allocation, scheduling and content-based, graceful, adaptive QoS support to these applications. We demonstrate the benefits of content-based adaptation and of dynamic structuring of distributed applications, using a set of video applications.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132947180","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776379
D. Tien, O. Villin, C. Bac
Multimedia applications require support for quality of service (QoS). The need for reusable and maintainable code also means that these kinds of applications are developed in a distributed object system. To address the support of QoS in middleware, we propose a lightweight model to manage QoS constraints in this kind of environment. This model is based on two types of objects: micro-QoS managers (/spl mu/QoS-Mngrs) and resource managers (R-Mngrs). A /spl mu/QoS-Mngr is associated with an application, and it handles the QoS contract, the QoS mapping and the QoS monitoring. Each R-Mngr is responsible for QoS management for a specific resource, including admission control, real-time scheduling and monitoring. The /spl mu/QoS-Mngrs and the R-Mngrs co-operate, using the middleware, to ensure end-to-end QoS management. This paper focuses on the R-Mngrs and it gives an overview of our implementation on a CORBA platform in the context of a video-on-demand (VOD) application.
{"title":"Resource managers for QoS in CORBA","authors":"D. Tien, O. Villin, C. Bac","doi":"10.1109/ISORC.1999.776379","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776379","url":null,"abstract":"Multimedia applications require support for quality of service (QoS). The need for reusable and maintainable code also means that these kinds of applications are developed in a distributed object system. To address the support of QoS in middleware, we propose a lightweight model to manage QoS constraints in this kind of environment. This model is based on two types of objects: micro-QoS managers (/spl mu/QoS-Mngrs) and resource managers (R-Mngrs). A /spl mu/QoS-Mngr is associated with an application, and it handles the QoS contract, the QoS mapping and the QoS monitoring. Each R-Mngr is responsible for QoS management for a specific resource, including admission control, real-time scheduling and monitoring. The /spl mu/QoS-Mngrs and the R-Mngrs co-operate, using the middleware, to ensure end-to-end QoS management. This paper focuses on the R-Mngrs and it gives an overview of our implementation on a CORBA platform in the context of a video-on-demand (VOD) application.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121417931","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776349
Danilo Beuche, A. Guerrouat, Holger Papajewski, Wolfgang Schröder-Preikschat, O. Spinczyk, Ute Spinczyk
Deeply embedded systems are forced to operate under extreme resource constraints in terms of memory, CPU, time and power consumption. Automotive systems are a typical example: today's limousines can be considered as (large-scale) distributed systems on wheels. There are cars in daily operation consisting of over 60 networked processors (i.e. microcontrollers). Conservative estimations suggest that, in the near future, every car will be equipped with about 20 networked microcontrollers, on average. The complexity of these "decentralized computer architectures" can no longer be managed by the application alone. Dedicated embedded operating systems are required to ensure the manageability, adaptability, portability and efficiency of the software. Resource-sparing operations under (hard) real-time constraints must be the maxim. This paper discusses the design and implementation of PURE (Portable Universal Runtime Executive) for these classes of deeply embedded systems.
{"title":"The PURE family of object-oriented operating systems for deeply embedded systems","authors":"Danilo Beuche, A. Guerrouat, Holger Papajewski, Wolfgang Schröder-Preikschat, O. Spinczyk, Ute Spinczyk","doi":"10.1109/ISORC.1999.776349","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776349","url":null,"abstract":"Deeply embedded systems are forced to operate under extreme resource constraints in terms of memory, CPU, time and power consumption. Automotive systems are a typical example: today's limousines can be considered as (large-scale) distributed systems on wheels. There are cars in daily operation consisting of over 60 networked processors (i.e. microcontrollers). Conservative estimations suggest that, in the near future, every car will be equipped with about 20 networked microcontrollers, on average. The complexity of these \"decentralized computer architectures\" can no longer be managed by the application alone. Dedicated embedded operating systems are required to ensure the manageability, adaptability, portability and efficiency of the software. Resource-sparing operations under (hard) real-time constraints must be the maxim. This paper discusses the design and implementation of PURE (Portable Universal Runtime Executive) for these classes of deeply embedded systems.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115898701","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776392
Kwang-Rok Kim
The following fundamental issues in establishing sound architectures for object oriented (OO) real time (RT) distributed computing systems (DCSs) are briefly discussed: (1) How much is the fixed priority assignment relevant to the activities of distributed object designers? (2) Can the event-triggered architecture and the time-triggered architecture be combined into a unified architecture?.
{"title":"Questionable relevancy of fixed priority assignment in distributed object design","authors":"Kwang-Rok Kim","doi":"10.1109/ISORC.1999.776392","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776392","url":null,"abstract":"The following fundamental issues in establishing sound architectures for object oriented (OO) real time (RT) distributed computing systems (DCSs) are briefly discussed: (1) How much is the fixed priority assignment relevant to the activities of distributed object designers? (2) Can the event-triggered architecture and the time-triggered architecture be combined into a unified architecture?.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121593716","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776393
H. Kopetz
A real time system must produce the intended results at the intended points of real time determined by its environment, otherwise the system has failed (H. Kopetz, 1997). For the purpose of this discussion, we consider two types of environments that contain real time computer systems: (i) static environments, where the frequency of the service requests on the computer system are constrained by a priori known environmental characteristics; (ii) dynamic environments, where it is possible to specify peak-load-service-request rates probabilistically only, e.g., a military command and control system that has to adapt dynamically to the n priori unknown threats of the enemy. We feel that these two fundamentally different environments of distributed real time computer systems demand different system models and different implementation strategies.
{"title":"Which models and architectures of distributed real-time computing systems suit which application area?","authors":"H. Kopetz","doi":"10.1109/ISORC.1999.776393","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776393","url":null,"abstract":"A real time system must produce the intended results at the intended points of real time determined by its environment, otherwise the system has failed (H. Kopetz, 1997). For the purpose of this discussion, we consider two types of environments that contain real time computer systems: (i) static environments, where the frequency of the service requests on the computer system are constrained by a priori known environmental characteristics; (ii) dynamic environments, where it is possible to specify peak-load-service-request rates probabilistically only, e.g., a military command and control system that has to adapt dynamically to the n priori unknown threats of the enemy. We feel that these two fundamentally different environments of distributed real time computer systems demand different system models and different implementation strategies.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131757742","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776365
Yasunori Matsui, Seiji Kihara, A. Mitsuzawa, S. Moriai, H. Tokuda
Adaptive QoS systems are attractive for multimedia services that are accessed via the Internet or mobile computers. An important feature of an adaptive QoS system is that it allows application programs to specify the QoS level desired, and at the system to set the level according to the resources available. With an adaptive QoS system, the user should specify not only the target QoS, but also a QoS range to minimize the quality degradation resulting from resource shortages. The paper introduces QoSPath as an extensible object model for specifying, translating, and arbitrating QoS in adaptive QoS systems. The QoSPath model herein lets users and application programs specify their QoS preference by setting QoSPoints in a QoSPath, each of which specifies an objective QoS level against a subjective utility value. With the QoSPath model, a simple QoS preference can be specified by a few parameters, while more detailed specifications can be given by providing more information, thus the model offers both the simple and descriptive QoS specifications. It is designed to be flexible in that new QoS formats and translation modules can be easily defined with only a minimum knowledge of other parts of a system. It therefore separates the functions of QoS specification, translation/inverse-translation and arbitration.
{"title":"An extensible object model for QoS specification in adaptive QoS systems","authors":"Yasunori Matsui, Seiji Kihara, A. Mitsuzawa, S. Moriai, H. Tokuda","doi":"10.1109/ISORC.1999.776365","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776365","url":null,"abstract":"Adaptive QoS systems are attractive for multimedia services that are accessed via the Internet or mobile computers. An important feature of an adaptive QoS system is that it allows application programs to specify the QoS level desired, and at the system to set the level according to the resources available. With an adaptive QoS system, the user should specify not only the target QoS, but also a QoS range to minimize the quality degradation resulting from resource shortages. The paper introduces QoSPath as an extensible object model for specifying, translating, and arbitrating QoS in adaptive QoS systems. The QoSPath model herein lets users and application programs specify their QoS preference by setting QoSPoints in a QoSPath, each of which specifies an objective QoS level against a subjective utility value. With the QoSPath model, a simple QoS preference can be specified by a few parameters, while more detailed specifications can be given by providing more information, thus the model offers both the simple and descriptive QoS specifications. It is designed to be flexible in that new QoS formats and translation modules can be easily defined with only a minimum knowledge of other parts of a system. It therefore separates the functions of QoS specification, translation/inverse-translation and arbitration.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130463712","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776361
T. Nishiyama
The issue of software development productivity with new technology has increasingly become an important topic within our corporation. However, with the increase in size and complexity of software, and the continuous demand for developers to deliver software within tight schedules, developers cannot readily afford to take the extra time needed to learn and incorporate new technologies into their development process. The paper introduces the concept of a "Process Warehouse" whose aim is to aid in the efficient introduction and transfer of a particular target technology into a software organization. A framework for the Process Warehouse and suggested methods for preparing technical information for the Process Warehouse are described. This concept has been used successfully to introduce object oriented technology (OOT) into projects and will be used as a base to create a similar Process Warehouse that concentrates on embedded real time OOT issues in the near future.
{"title":"Using a \"Process Warehouse\" concept: a practical method for successful technology transfer","authors":"T. Nishiyama","doi":"10.1109/ISORC.1999.776361","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776361","url":null,"abstract":"The issue of software development productivity with new technology has increasingly become an important topic within our corporation. However, with the increase in size and complexity of software, and the continuous demand for developers to deliver software within tight schedules, developers cannot readily afford to take the extra time needed to learn and incorporate new technologies into their development process. The paper introduces the concept of a \"Process Warehouse\" whose aim is to aid in the efficient introduction and transfer of a particular target technology into a software organization. A framework for the Process Warehouse and suggested methods for preparing technical information for the Process Warehouse are described. This concept has been used successfully to introduce object oriented technology (OOT) into projects and will be used as a base to create a similar Process Warehouse that concentrates on embedded real time OOT issues in the near future.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125745675","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776396
C. Montez, J. Fraga, J. Farines, R. S. Oliveira
CORBA is an emerging middleware infrastructure with open standardization that is receiving a good acceptance since it allows easier programming of distributed objects. CORBA is being extended through the specification of interfaces and necessary abstractions to support applications with real time constraints. These new abstractions will enable a variety of programming models for real time applications. The paper presents an adaptive programming model for distributed real time applications using CORBA concepts. The model combines the time polymorphic invocation technique with the (m,k)-firm guarantee.
{"title":"An adaptive scheduling approach in real-time CORBA","authors":"C. Montez, J. Fraga, J. Farines, R. S. Oliveira","doi":"10.1109/ISORC.1999.776396","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776396","url":null,"abstract":"CORBA is an emerging middleware infrastructure with open standardization that is receiving a good acceptance since it allows easier programming of distributed objects. CORBA is being extended through the specification of interfaces and necessary abstractions to support applications with real time constraints. These new abstractions will enable a variety of programming models for real time applications. The paper presents an adaptive programming model for distributed real time applications using CORBA concepts. The model combines the time polymorphic invocation technique with the (m,k)-firm guarantee.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134198196","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 : 1999-05-02DOI: 10.1109/ISORC.1999.776398
E. Anceaume, G. Cabillic, Pascal Chevochot, I. Puaut
Typically, most distributed, dependable, real time systems designed in the past can only meet the particular requirements of the application domain to which they were targeted. This approach led to specific, non flexible, dedicated and non reusable solutions, often based on specialized hardware. The paper presents an alternative approach where a flexible run time support for distributed dependable hard real time applications is built on top of off-the-shelf hardware. This support has been designed by considering three fundamental and complementary aspects: real time, to support applications that exhibit strict timing constraints; fault tolerance, to provide a high degree of reliability through the transparent provision of fault tolerant mechanisms; and flexibility, to allow the modifications of components of the run time support without having to rewrite it entirely, and to support a large range of application domains, real time kernels and hardware.
{"title":"A flexible run-time support for distributed dependable hard real-time applications","authors":"E. Anceaume, G. Cabillic, Pascal Chevochot, I. Puaut","doi":"10.1109/ISORC.1999.776398","DOIUrl":"https://doi.org/10.1109/ISORC.1999.776398","url":null,"abstract":"Typically, most distributed, dependable, real time systems designed in the past can only meet the particular requirements of the application domain to which they were targeted. This approach led to specific, non flexible, dedicated and non reusable solutions, often based on specialized hardware. The paper presents an alternative approach where a flexible run time support for distributed dependable hard real time applications is built on top of off-the-shelf hardware. This support has been designed by considering three fundamental and complementary aspects: real time, to support applications that exhibit strict timing constraints; fault tolerance, to provide a high degree of reliability through the transparent provision of fault tolerant mechanisms; and flexibility, to allow the modifications of components of the run time support without having to rewrite it entirely, and to support a large range of application domains, real time kernels and hardware.","PeriodicalId":211905,"journal":{"name":"Proceedings 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (ISORC'99) (Cat. No.99-61702)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124949495","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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