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DeeDS towards a distributed and active real-time database system

S. F. Andler, J. Hansson, J. Eriksson, J. Mellin, M. Berndtsson, B. Eftring
1996 SIGMOD record  
Each critical transaction will have a contingency plan with reduced computational requirements, which is invoked when the original transaction cannot meet its deadline.  ...  The DeeDS prototype represents a unique integration of several advanced concepts such as active functionality, distribution, and real-time database systems with hard and soft deadlines.  ... 
doi:10.1145/381854.381881 fatcat:byp757baj5di5lqyrvxgnbwu3e

An Overview of Real-Time Database Systems [chapter]

Ben Kao, Hector Garcia-Molina
1994 Real Time Computing  
The resulting integrated system, which provides database operations with real-time constraints is generally called a real-time database system RTDBS 1 .  ...  However, as a part of a real-time system, whose tasks" are associated with time constraints, a RTDBS, has the added burden of ensuring some degree of con dence in meeting the system's timing requirements  ...  So far we h a ve assumed that real-time constraints are speci ed on the transactions. Korth et. al. 32 propose a di erent model with which deadlines are associated with consistency constraints.  ... 
doi:10.1007/978-3-642-88049-0_13 dblp:conf/nato/KaoG92 fatcat:k6m5p2owbvgrxd6zb2226vmf5u

Research issues in real-time database systems Survey paper

O Ulusoy
1995 Information Sciences  
Efficient database management algorithms for accessing and manipulating data are required to satisfy timing constraints of supported applications.  ...  Some new criteria need to be developed to involve timing constraints of real-time applications in many database systems design issues, such as transaction/query processing, data buffering, CPU, and IO  ...  Three basic concepts explored in this project are active database management, timing constraints, and contingency plans.  ... 
doi:10.1016/0020-0255(95)00130-1 fatcat:xpbewsfa3vb3jlbzxinnqehldy

A Compressed Technique to Optimize the Processing of Real Time Data in Centralized and Client-Server Data Base Systems

Amit Sinha, Rajendra Kr. Isaac
2015 International Journal of Computer Applications  
It depends on various constraints of architecture such as data size, bandwidth speed, network latency and machine configuration etc.  ...  Varshney, L.R., (2014), On code design for simultaneous energy and information transfer,  ...  LITERATURE REVIEW Nandanwar et al (2013) said that time constraint was the main factor in real time operating system and it affected the deadline of the process.  ... 
doi:10.5120/20179-2392 fatcat:mdyteunconfqfewpljf7sxxeui

MRDB: a Multi-user Real-time DataBase testbed

Son, Young-Kuk Kim, Beckinger
1994 Proceedings of the Twenty-Seventh Hawaii International Conference on System Sciences HICSS-94  
Transactions in real-time database systems should be scheduled considering both data consistency and timing constraints.  ...  In addition, a real-time database must adapt to changes in the operating environment and guarantee the completion of critical tasks.  ...  Conventional database systems, however, do not stress the notion of time constraints or deadlines with respect to transactions.  ... 
doi:10.1109/hicss.1994.323229 fatcat:bekqllo5sbbohoos5dx77lxzgy

Task Scheduling Algorithms for Fault Tolerance in Real-Time Embedded Systems [chapter]

Nagarajan Kandasamy, John P. Hayes, Brian T. Murray
2000 Dependable Network Computing  
We conclude with a brief discussion of scheduling and fault-tolerance issues related to safety-critical embedded systems.  ...  , timing accuracy, and quality of service.  ...  However, it is difficult to guarantee deadlines using dynamic scheduling techniques in the case of complex tasks with precedence, synchronization, and exclusion constraints executing in a distributed environment  ... 
doi:10.1007/978-1-4615-4549-1_18 fatcat:t7i43wk7uza4tapn4xx4sfeigy

Transaction processing in distributed active real-time database systems

Özgür Ulusoy
1998 Journal of Systems and Software  
An active real-time database system (ARTDBS) is designed to provide timely response to the critical situations that are de®ned on database states.  ...  The performance metric used in the evaluations is the fraction of transactions that violate their timing constraints.  ...  Three basic concepts explored in this project are active database management, timing constraints, and contingency plans.  ... 
doi:10.1016/s0164-1212(98)10013-4 fatcat:giyuzk2lzngqvavsixgtctcibi

Supporting the requirements for multi-level secure and real-time databases in distributed environments [chapter]

Sang H. Son, Craig Chaney
1998 IFIP Advances in Information and Communication Technology  
Conflicts in database systems with both real-time and security requirements can sometimes be unresolvable.  ...  In order to help the designers, we developed a tool that scans a database specification and finds all unresolvable conflicts.  ...  The resulting integrated system, which provides database operations with real-time constraints is generally called a real-time database system.  ... 
doi:10.1007/978-0-387-35285-5_5 fatcat:uwnjcebkabhgdo7xfg6dtmnmya

Scheduling algorithms and operating systems support for real-time systems

K. Ramamritham, J.A. Stankovic
1994 Proceedings of the IEEE  
and present several exemplars of each.  ...  This paper summarizes the state of the real-time field in the areas of scheduling and operating system kernels.  ...  , and developing and performing experimental studies on real-time distributed database protocols.  ... 
doi:10.1109/5.259426 fatcat:pxwm26c4wvgdfczwql6blmvwky

TerraSAR-X Mission Planning System: Automated Command Generation for Spacecraft Operations

E. Maurer, F. Mrowka, A. Braun, M.P. Geyer, C. Lenzen, Y. Wasser, M. Wickler
2010 IEEE Transactions on Geoscience and Remote Sensing  
The purpose of this paper is to describe the concepts and the TerraSAR-X realization of the Mission Planning System.  ...  The user community requesting SAR products is composed of commercial and scientific partners as documented in a Public-Private-Partnership (PPP) agreement.  ...  Experience from the TerraSAR-X mission revealed that a direct and flexible access to the MPS database is necessary in spacecraft and ground contingency cases.  ... 
doi:10.1109/tgrs.2009.2033469 fatcat:ajserbiblnelxo7ov5tj5qrqra

IEEE Transactions on Geoscience and Remote Sensing publication information

2010 IEEE Transactions on Geoscience and Remote Sensing  
The purpose of this paper is to describe the concepts and the TerraSAR-X realization of the Mission Planning System.  ...  The user community requesting SAR products is composed of commercial and scientific partners as documented in a Public-Private-Partnership (PPP) agreement.  ...  Experience from the TerraSAR-X mission revealed that a direct and flexible access to the MPS database is necessary in spacecraft and ground contingency cases.  ... 
doi:10.1109/tgrs.2010.2040699 fatcat:ntvl3x4ijbcbligdexc3wel22u

REaltime ACtive Heterogeneous Systems - Where Did We Reach After REACH? [chapter]

Thomas Kudraß
2010 Lecture Notes in Computer Science  
During that time the Database and Distributed Systems group (DVS) led by Alejandro Buchmann has made lots of contributions to the development of those ideas by many research projects.  ...  This paper gives a survey of the deployment of ideas from the area of real-time, active and heterogeneous database systems in the years from 1991 to 2010 as they have been embraced by IT industry.  ...  Many of the problems and the ideas we discussed in that time appeared in application scenarios and IT trends I encountered later.  ... 
doi:10.1007/978-3-642-17226-7_3 fatcat:tuezftccdneqhiojq6rjwu74yi

An Autonomous Spacecraft Agent Prototype [chapter]

Barney Pell, Douglas E. Bernard, Steve A. Chien, Erann Gat, Nicola Muscettola, P. Pandurang Nayak, Michael D. Wagner, Brian C. Williams
1998 Autonomous Agents  
This architecture integrates traditional real-time monitoring and control with constraintbased planning and scheduling, robust multi-threaded execution, and model-based diagnosis and recon guration.  ...  We implemented a prototype autonomous spacecraft agent within the architecture and demonstrated the prototype in the context of a challenging autonomous mission scenario on a simulated spacecraft.  ...  ACKNOWLEDGMENTS The research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA and at the NASA Ames Research Center.  ... 
doi:10.1007/978-1-4615-5735-7_4 fatcat:rg73ii2rejdkhe5ths6esdr43m

An autonomous spacecraft agent prototype

Barney Pell, Douglas E. Bernard, Steve A. Chien, Erann Gat, Nicola Muscettola, P. Pandurang Nayak, Michael D. Wagner, Brian C. Williams
1997 Proceedings of the first international conference on Autonomous agents - AGENTS '97  
This architecture integrates traditional real-time monitoring and control with constraintbased planning and scheduling, robust multi-threaded execution, and model-based diagnosis and recon guration.  ...  We implemented a prototype autonomous spacecraft agent within the architecture and demonstrated the prototype in the context of a challenging autonomous mission scenario on a simulated spacecraft.  ...  ACKNOWLEDGMENTS The research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA and at the NASA Ames Research Center.  ... 
doi:10.1145/267658.267724 dblp:conf/agents/PellBCGMNWW97 fatcat:yrm4kc6cejat7cjrq6pox3gza4

Characterizing IS Development Projects [chapter]

Kees Slooten, Bert Hodes
1996 Method Engineering  
The relationship between project context and project situation is described by defining a number of contingency factors and components of a project approach.  ...  Relationships between contingency factors and the components of the project approach are analyzed for nine non-standard projects of the systems development department of a bank organization.  ...  CONTINGENCIES AND CONSTRAINTS The contingency model The contingency model of this research is based on the situated method engineering approach of figure 1.  ... 
doi:10.1007/978-0-387-35080-6_3 fatcat:dloqv6s4dngplp4pqoywckmbwm
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