Pub Date : 1995-05-15DOI: 10.1109/RTTAS.1995.516203
R. Rajkumar, M. Gagliardi, L. Sha
Distributed real-time systems are becoming more pervasive in many domains including process control, discrete manufacturing, defense systems, air traffic control, and online monitoring systems in medicine. The construction of such systems, however, is impeded by the lack of simple yet powerful programming models and the lack of efficient, scalable, dependable and analyzable interfaces and their implementations. We argue that these issues need to be resolved with powerful application-level toolkits similar to that provided by ISIS. We consider the inter-process communication requirements which form a fundamental block in the construction of distributed real-time systems. We propose the real-time publisher/subscriber model, a variation of group-based programming and anonymous communication techniques, as a model for distributed real-time inter-process communication which can address issues of programming ease, portability, scalability and analyzability. The model has been used successfully in building a software architecture for building upgradable real-time systems. We provide the programming interface, a detailed design and implementation details of this model along with some preliminary performance benchmarks. The results are encouraging in that the goals we seek look achievable.
{"title":"The real-time publisher/subscriber inter-process communication model for distributed real-time systems: design and implementation","authors":"R. Rajkumar, M. Gagliardi, L. Sha","doi":"10.1109/RTTAS.1995.516203","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516203","url":null,"abstract":"Distributed real-time systems are becoming more pervasive in many domains including process control, discrete manufacturing, defense systems, air traffic control, and online monitoring systems in medicine. The construction of such systems, however, is impeded by the lack of simple yet powerful programming models and the lack of efficient, scalable, dependable and analyzable interfaces and their implementations. We argue that these issues need to be resolved with powerful application-level toolkits similar to that provided by ISIS. We consider the inter-process communication requirements which form a fundamental block in the construction of distributed real-time systems. We propose the real-time publisher/subscriber model, a variation of group-based programming and anonymous communication techniques, as a model for distributed real-time inter-process communication which can address issues of programming ease, portability, scalability and analyzability. The model has been used successfully in building a software architecture for building upgradable real-time systems. We provide the programming interface, a detailed design and implementation details of this model along with some preliminary performance benchmarks. The results are encouraging in that the goals we seek look achievable.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114394443","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516207
D. Niehaus, J. Stankovic, K. Ramamritham
Building complex real-time systems requires languages and tools that permit careful specification of the system design as well as providing automatic calculation and analysis. If this design and analysis environment is well done, it should be able to accommodate modification of the system design through simple specification changes and then rerunning the analysis tools. A critical aspect of such an environment is simultaneous support for conflicting goals: design by layered abstractions which conceal implementation details, and accounting for those implementation details which are necessary to ascertain timing correctness. In this paper, we discuss the implementation of a system description language (SDL) that is part of an environment developed to address these problems. We have experimented with the SDL in several applications including a robotic pick-and-place circuit board assembly, flexible manufacturing, and a distributed real-time scheduling simulation. In each case, the SDL provided significant benefits with regard to ease of modification, timing analysis and automatic linking and loading of the target system.
{"title":"A real-time system description language","authors":"D. Niehaus, J. Stankovic, K. Ramamritham","doi":"10.1109/RTTAS.1995.516207","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516207","url":null,"abstract":"Building complex real-time systems requires languages and tools that permit careful specification of the system design as well as providing automatic calculation and analysis. If this design and analysis environment is well done, it should be able to accommodate modification of the system design through simple specification changes and then rerunning the analysis tools. A critical aspect of such an environment is simultaneous support for conflicting goals: design by layered abstractions which conceal implementation details, and accounting for those implementation details which are necessary to ascertain timing correctness. In this paper, we discuss the implementation of a system description language (SDL) that is part of an environment developed to address these problems. We have experimented with the SDL in several applications including a robotic pick-and-place circuit board assembly, flexible manufacturing, and a distributed real-time scheduling simulation. In each case, the SDL provided significant benefits with regard to ease of modification, timing analysis and automatic linking and loading of the target system.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"23 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113964140","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516190
Kevin A. Kettler, Daniel I. Katcher, J. Strosnider
Real-time scheduling theory attempts to guarantee that a real-time task set always meets its deadlines. Historically, there has existed a wide gap between real-time scheduling theory and the reality of applying the theory to task sets implemented via real-time operating systems (RTOSs). The paper provides a framework to account for implementation costs in real-time scheduling theory. In addition, an engineering methodology that allows users and developers to accurately model and evaluate RTOSs is presented. We use this methodology to model three different commercial real-time operating systems that are being used in multimedia applications. We show how to use the RTOS scheduling models to evaluate the performance and design of RTOSs.
{"title":"A modeling methodology for real-time/multimedia operating systems","authors":"Kevin A. Kettler, Daniel I. Katcher, J. Strosnider","doi":"10.1109/RTTAS.1995.516190","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516190","url":null,"abstract":"Real-time scheduling theory attempts to guarantee that a real-time task set always meets its deadlines. Historically, there has existed a wide gap between real-time scheduling theory and the reality of applying the theory to task sets implemented via real-time operating systems (RTOSs). The paper provides a framework to account for implementation costs in real-time scheduling theory. In addition, an engineering methodology that allows users and developers to accurately model and evaluate RTOSs is presented. We use this methodology to model three different commercial real-time operating systems that are being used in multimedia applications. We show how to use the RTOS scheduling models to evaluate the performance and design of RTOSs.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134548912","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516210
C. W. Mercer, R. Rajkumar
Real-time applications in dynamic systems such as multimedia systems may change their timing characteristics on the fly and may be created and terminated at any time. A priori resource allocation decisions may not hold throughout the lifetime of such applications because of changing user needs and interests. The ability to monitor and control system resources dynamically is fundamental to building flexible and dynamic multimedia systems. In this paper, we describe the mechanisms and tools we have built for monitoring and controlling operating system resource reserves in Real-Time Mach. The system supports a resource reservation abstraction called 'processor capacity reserves', and an interactive tool named 'rmon' uses these mechanisms to display the processor usage for each reserved activity in the system and to allow the user to change the processor reservation dynamically; it can also coordinate the reservation change requests with a separate quality-of-service manager which makes policy decisions regarding which requests are granted.
{"title":"An interactive interface and RT-Mach support for monitoring and controlling resource management","authors":"C. W. Mercer, R. Rajkumar","doi":"10.1109/RTTAS.1995.516210","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516210","url":null,"abstract":"Real-time applications in dynamic systems such as multimedia systems may change their timing characteristics on the fly and may be created and terminated at any time. A priori resource allocation decisions may not hold throughout the lifetime of such applications because of changing user needs and interests. The ability to monitor and control system resources dynamically is fundamental to building flexible and dynamic multimedia systems. In this paper, we describe the mechanisms and tools we have built for monitoring and controlling operating system resource reserves in Real-Time Mach. The system supports a resource reservation abstraction called 'processor capacity reserves', and an interactive tool named 'rmon' uses these mechanisms to display the processor usage for each reserved activity in the system and to allow the user to change the processor reservation dynamically; it can also coordinate the reservation change requests with a separate quality-of-service manager which makes policy decisions regarding which requests are granted.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127400062","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516202
J. Ng, Ge Nong
In order to support multimedia applications on top of a network, the underlying network must transfer the data which include text, graphics, images, audio, and video promptly and correctly. Recent development in high-speed local area networks such as FDDI is capable of supporting such applications. Moreover, there is a trend showing that different kinds of networks can be interconnected by ATM (asynchronous transfer mode) switches. In view of this, a series of simulation experiments have been conducted to investigate the effects of ATM switches for internetworks multimedia applications under different network parameters.
{"title":"Multimedia applications on FDDI networks connected by an ATM switch","authors":"J. Ng, Ge Nong","doi":"10.1109/RTTAS.1995.516202","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516202","url":null,"abstract":"In order to support multimedia applications on top of a network, the underlying network must transfer the data which include text, graphics, images, audio, and video promptly and correctly. Recent development in high-speed local area networks such as FDDI is capable of supporting such applications. Moreover, there is a trend showing that different kinds of networks can be interconnected by ATM (asynchronous transfer mode) switches. In view of this, a series of simulation experiments have been conducted to investigate the effects of ATM switches for internetworks multimedia applications under different network parameters.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"133 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116071272","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516197
D. Sides
The Johns Hopkins University Applied Physics Laboratory (JHU/APL), sponsored by the Oceanographer of the Navy and the Commander of the Submarine Development Squadron Twelve, has produced a real time data acquisition and display system to allow U.S. submarines to measure the in-situ ocean environment during standard patrol operations. The system is composed of a dynamically adaptable architecture that allows for a variety oceanographic data sensor sources in a "plug and play" fashion. This adaptability is carried throughout the system in terms of configuration management, data acquisition, calibration, processing and display of the available data. Faulted sensor packages can be replaced seamlessly, and previously unknown sensor types can be added, all with no software impact. At the heart of this architecture is the "Data Dictionary", a dynamically configurable data base that describes all aspects of the sensor data necessary to carry out the system objectives.
{"title":"A dynamically adaptable real time data acquisition and display system","authors":"D. Sides","doi":"10.1109/RTTAS.1995.516197","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516197","url":null,"abstract":"The Johns Hopkins University Applied Physics Laboratory (JHU/APL), sponsored by the Oceanographer of the Navy and the Commander of the Submarine Development Squadron Twelve, has produced a real time data acquisition and display system to allow U.S. submarines to measure the in-situ ocean environment during standard patrol operations. The system is composed of a dynamically adaptable architecture that allows for a variety oceanographic data sensor sources in a \"plug and play\" fashion. This adaptability is carried throughout the system in terms of configuration management, data acquisition, calibration, processing and display of the available data. Faulted sensor packages can be replaced seamlessly, and previously unknown sensor types can be added, all with no software impact. At the heart of this architecture is the \"Data Dictionary\", a dynamically configurable data base that describes all aspects of the sensor data necessary to carry out the system objectives.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132899183","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516191
S. Oikawa, H. Tokuda
Timing management for user-level real-time threads can be done with appropriate support of the kernel. When a specified time comes, the kernel makes a virtual processor to upcall a user-level scheduler for its timing management. Then, the timing management can suffer from the overhead of a user-level scheduler. The paper presents an efficient timing management mechanism for user-level real-time threads. By sharing user-level timers through the shared kernel/user structure and keeping the appropriate hints for them, redundant processing of them and events can be eliminated. The results of the performance evaluations show that the upcall performance of our user-level real-time threads is comparable to and more stable than that of kernel-provided real-time threads.
{"title":"Efficient timing management for user-level real-time threads","authors":"S. Oikawa, H. Tokuda","doi":"10.1109/RTTAS.1995.516191","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516191","url":null,"abstract":"Timing management for user-level real-time threads can be done with appropriate support of the kernel. When a specified time comes, the kernel makes a virtual processor to upcall a user-level scheduler for its timing management. Then, the timing management can suffer from the overhead of a user-level scheduler. The paper presents an efficient timing management mechanism for user-level real-time threads. By sharing user-level timers through the shared kernel/user structure and keeping the appropriate hints for them, redundant processing of them and events can be eliminated. The results of the performance evaluations show that the upcall performance of our user-level real-time threads is comparable to and more stable than that of kernel-provided real-time threads.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133754980","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516204
R. Games, A. Kanevsky, P. Krupp, L. Monk
Can general purpose commercial massively parallel processors (MPPs) be used for computationally intensive real-time applications that have traditionally required a custom arrangement of special-purpose computers and mainframes? If so, then the enormous lifecycle costs of many systems needed by, for instance, the Government could potentially be reduced. The components would be commercially available and continuing technological advances could more easily be incorporated into existing systems. Relevant applications have requirements not found in large-scale scientific computing, which has up to now provided most of the motivation for the development of MPPs. Perhaps the most important difference is the need for real-time processing. Depending on the application, multi-level security, fault tolerance and other features may also be necessary. There have already been hardware advances that may make such a high performance computing solution possible. However, daunting software challenges remain. We focus on one critical problem, the real-time scheduling of the communications between processing nodes. We discuss real-time MPP application benchmarks.
{"title":"Real-time communications scheduling for massively parallel processors","authors":"R. Games, A. Kanevsky, P. Krupp, L. Monk","doi":"10.1109/RTTAS.1995.516204","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516204","url":null,"abstract":"Can general purpose commercial massively parallel processors (MPPs) be used for computationally intensive real-time applications that have traditionally required a custom arrangement of special-purpose computers and mainframes? If so, then the enormous lifecycle costs of many systems needed by, for instance, the Government could potentially be reduced. The components would be commercially available and continuing technological advances could more easily be incorporated into existing systems. Relevant applications have requirements not found in large-scale scientific computing, which has up to now provided most of the motivation for the development of MPPs. Perhaps the most important difference is the need for real-time processing. Depending on the application, multi-level security, fault tolerance and other features may also be necessary. There have already been hardware advances that may make such a high performance computing solution possible. However, daunting software challenges remain. We focus on one critical problem, the real-time scheduling of the communications between processing nodes. We discuss real-time MPP application benchmarks.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116021338","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516222
S. Venglar, T. Urbanik, Jyh-Charn S. Liu
Due to the complexity of road traffic movements occurring within urban interchanges and increasing levels of demand, many diamond interchanges on roads are experiencing serious congestion. The closely spaced traffic signals with high volume turning traffic create a complex control scenario. The diamond interchange offers the unique opportunity to integrate many innovative technologies into a system that is small enough to be manageable, yet complex enough to present a challenging control environment. Developing a real time, multi modal, traffic adaptive interchange control system is a research objective of the Intelligent Vehicle Highway System (IVHS) Research Center of Excellence Program of the Texas Transportation Institute. This research effort will integrate a variety of technologies into a single control system that will increase traffic performance and demonstrate IVHS concepts in advanced traffic management systems. Through the use of video imaging equipment, traffic information processing, and real time optimization and control, road users will experience less delay, less congestion and fewer safety problems at diamond interchanges.
{"title":"Real-time optimization at diamond interchanges","authors":"S. Venglar, T. Urbanik, Jyh-Charn S. Liu","doi":"10.1109/RTTAS.1995.516222","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516222","url":null,"abstract":"Due to the complexity of road traffic movements occurring within urban interchanges and increasing levels of demand, many diamond interchanges on roads are experiencing serious congestion. The closely spaced traffic signals with high volume turning traffic create a complex control scenario. The diamond interchange offers the unique opportunity to integrate many innovative technologies into a system that is small enough to be manageable, yet complex enough to present a challenging control environment. Developing a real time, multi modal, traffic adaptive interchange control system is a research objective of the Intelligent Vehicle Highway System (IVHS) Research Center of Excellence Program of the Texas Transportation Institute. This research effort will integrate a variety of technologies into a single control system that will increase traffic performance and demonstrate IVHS concepts in advanced traffic management systems. Through the use of video imaging equipment, traffic information processing, and real time optimization and control, road users will experience less delay, less congestion and fewer safety problems at diamond interchanges.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121364364","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516213
Too-Seng Tia, Z. Deng, M. Shankar, M. Storch, Jun Sun, L.-C. Wu, J. Liu
Describes how the scheduling algorithms and schedulability analysis methods developed for periodic tasks can be extended to provide performance guarantees to semi-periodic tasks. Like periodic tasks, the requests in a semi-periodic task are released regularly. However, their computation times vary widely. We focus on systems where the total maximum utilization of the tasks on each processor is larger than one. Hence, according to the existing schedulability conditions for periodic tasks, we cannot guarantee that the semi-periodic tasks are schedulable, even though their total average utilization is very small. We describe two methods of providing probabilistic schedulability guarantees to the semi-periodic tasks. The first method, called probabilistic time-demand analysis, is a modification of the exact schedulability test for periodic tasks. The second method, called the transform-task method, transforms each task into a periodic task followed by a sporadic task. The transform-task method can provide an absolute guarantee to requests with shorter computation times and a probabilistic guarantee to the longer requests.
{"title":"Probabilistic performance guarantee for real-time tasks with varying computation times","authors":"Too-Seng Tia, Z. Deng, M. Shankar, M. Storch, Jun Sun, L.-C. Wu, J. Liu","doi":"10.1109/RTTAS.1995.516213","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516213","url":null,"abstract":"Describes how the scheduling algorithms and schedulability analysis methods developed for periodic tasks can be extended to provide performance guarantees to semi-periodic tasks. Like periodic tasks, the requests in a semi-periodic task are released regularly. However, their computation times vary widely. We focus on systems where the total maximum utilization of the tasks on each processor is larger than one. Hence, according to the existing schedulability conditions for periodic tasks, we cannot guarantee that the semi-periodic tasks are schedulable, even though their total average utilization is very small. We describe two methods of providing probabilistic schedulability guarantees to the semi-periodic tasks. The first method, called probabilistic time-demand analysis, is a modification of the exact schedulability test for periodic tasks. The second method, called the transform-task method, transforms each task into a periodic task followed by a sporadic task. The transform-task method can provide an absolute guarantee to requests with shorter computation times and a probabilistic guarantee to the longer requests.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"03 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127191810","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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