We have studied “Cellular Robotic System (CEBOT)”, which consists of many kinds of units called “cell”. CEBOT is required to be able to carry out many sorts of tasks under various surroundings. But it is impossibl...
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We have studied “Cellular Robotic System (CEBOT)”, which consists of many kinds of units called “cell”. CEBOT is required to be able to carry out many sorts of tasks under various surroundings. But it is impossible for CEBOT to install all sorts of the task execution procedures. Then CEBOT should be able to generate task execution procedures for a new task by reconfigurating himself. In this paper, we propose a new kind of the distributed intelligence system which is based on the concept of CEBOT. This proposed intelligence system has the abilities of learning, reasoning, and self-organizing. As similar to the hardware structure of CEBOT, this system consists of various kinds of intelligence units called “knowledge-cell”. By using the knowledge-cells and the proposed algorithms, the system which can generate task procedures is realized. Some simulations are also shown for demonstrating the self-organization and self-evolution abilities of the distributed intelligence system.
Real-time database systems must maintain consistency while minimizing the number of transactions that miss the deadline. To satisfy both the consistency and real-time constraints, there is the need to integrate synchr...
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Real-time database systems must maintain consistency while minimizing the number of transactions that miss the deadline. To satisfy both the consistency and real-time constraints, there is the need to integrate synchr...
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Real-time database systems must maintain consistency while minimizing the number of transactions that miss the deadline. To satisfy both the consistency and real-time constraints, there is the need to integrate synchronization protocols with real-time priority scheduling protocols. This paper describes a prototyping environment for investigating distributed real-time database systems, and its use for performance evaluation of priority-based scheduling protocols for real-time database systems.
This paper discusses how existing and proposed database Language SQL and Remote database Access (RDA) standards can fulfill critical operational requirements for data management. SQL and RDA are but two components of ...
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This paper discusses how existing and proposed database Language SQL and Remote database Access (RDA) standards can fulfill critical operational requirements for data management. SQL and RDA are but two components of a family of data management standards needed to meet requirements for emerging distributed processing systems. Requirements for needed capabilities such as object-oriented database, distributed database, and database export/import are discussed.
This article presents a scheme called "Difference Table" for maintaining database snapshots stored at sites remote from a central database which are refreshed only upon user request. database snapshots are c...
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This article presents a scheme called "Difference Table" for maintaining database snapshots stored at sites remote from a central database which are refreshed only upon user request. database snapshots are currently in widespread use where a subset of the central database is extracted and transmitted to a local workstation and utilized for decision support. The Difference Table method checks each update to a central database table against the definition of the snapshot. If the update is relevant, its effect is stored in a difference table. On receiving the refresh request. the contents of the difference table are transmitted to the remote site where they update the snapshot. The Difference Table scheme allows a selective refresh of the snapshot. in the sense that only the changes to a snapshot since the last refresh are transmitted. We discuss the additional database tables and processes required to support the Difference Table scheme. Performance measures are developed, and both quantitative and qualitative comparisons are made to alternative methods such as full regeneration and the approach used by System R*. By most criteria and in many environments, the Difference Table scheme is preferable to these alternatives. It also has several attractive side benefits which are not available in alternative methods.
The existing heterogeneous distributed database management systems (HDDBMSs) which are business-oriented will not be able to adequate for many new and developing information processing applications. The important obje...
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This paper presents a distributed data base management system for serving high reliable supervisory control systems based on local area network. It is supposed that the distributed control system is built of the hosts...
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In this paper, the effects of two-phase locking on the performance of a distributed database management system are evaluated. In particular, the relationship between the average transaction response time for four conc...
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In this paper, the effects of two-phase locking on the performance of a distributed database management system are evaluated. In particular, the relationship between the average transaction response time for four concurrency control algorithms based on two-phase locking has been established with respect to the static degree of interference for a given multiprogramming level, database size, and transaction size. The increase in average probability of one lock request conflicting with another has been measured with respect to the static degree of interference and the percentage of aborted transactions has been measured for each algorithm. In addition, the impact of a number of parameters (e.g. data replication, lock predeclaration, time-out, local processing time, degree of locality of references, interarrival time, number of nodes and transmission time) on the performance of a distributed database management system in the presence of a concurrency control mechanism has also been measured. The study has been made using simulation and the SIMULA programming language.
This paper presents a distributed data base management system for serving high reliable supervisory control systems based on local area network. It is supposed that the distributed control system is built of the hosts...
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This paper presents a distributed data base management system for serving high reliable supervisory control systems based on local area network. It is supposed that the distributed control system is built of the hosts which can replace each other and the database management system is provided for services which aid the organization switch on function from the breakdown host to the working host.
The existing heterogeneous distributed database management systems (HDDBMSs) which are business-oriented will not be able to adequate for many new and developing information processing applications. The important obje...
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The existing heterogeneous distributed database management systems (HDDBMSs) which are business-oriented will not be able to adequate for many new and developing information processing applications. The important objectives of these applications include the processing of complex objects and intelligence. Our approach is integrating logic and object paradigm to provide knowledge representation and inference mechanism in HDDBMS. This paper decribes the knowledge representation in object-oriented heterogeneous distributed database system with semantic association -- OHDDB-DG1, presents the method of processing constraints and rules in the global language OSAL which is Object-oriented and of Semantic Association with Logic, and explains briefly the peculiarities of processing inheritance and recursive inference.
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