Showing papers on "Data access published in 1981"

Method for the dynamic replication of data under distributed system control to control utilization of resources in a multiprocessing, distributed data base system

Abstract: A method for dynamic replication of data under distributed system control to control the utilization of resources in a multiprocessing, distributed data base system. Previously, systems providing for data replication at nodes of a multiprocessing, distributed data base system required that a central node maintain control, or that replicated data be synchronized by immediately conforming all copies of an updated data item. By this invention, requests for access to data of a specified currency are permitted and conformation of updated data is selectively deferred by use of a control procedure implemented at each node and utilizing a status and control (SAC) filed at each node which describes that node's view of the status for shared data items at other nodes.

The implementation of GERM, an entity-relationship data base management system

Abstract: The implementation of GERM, a data base management system based on the Entity-Relationship model, is presented. GERM is an end-user system providing complete facilities for interactive data base management, including retrieval, browsing, update, definition and reporting. The system has a modular design with the functional components arranged hierarchically. This paper discusses two specific areas, utility components and data access components. The data access components are layered, each approaching data access at a different level of abstraction. An example retrieval request is used to demonstrate how the components interact.

Use of a Relational Database to Support Clinical Research: Application in a Diabetes Program

Abstract: A database has been established to support conduct of clinical research and monitor delivery of medical care for 1200 diabetic patients as part of the Michigan Diabetes Research and Training Center (MDRTC). Use of an intelligent microcomputer to enter and retrieve the data and use of a relational database management system (DBMS) to store and manage data have provided a flexible, efficient method of achieving both support of small projects and monitoring overall activity of the Diabetes Center Unit (DCU). Simplicity of access to data, efficiency in providing data for unanticipated requests, ease of manipulations of relations, security and “logical data independence” were important factors in choosing a relational DBMS. The ability to interface with an interactive statistical program and a graphics program is a major advantage of this system. Out database currently provides support for the operation and analysis of several ongoing research projects.

IV. Clinical Consultation Systems, Medical Decision Support Systems and Clinical Research Data Bases: B. Clinical Research Data Bases: Use of a Relational Database to Support Clinical Research: Application in a Diabetes Program

Abstract: A database has been established to support conduct of clinical research and monitor delivery of medical care for 1200 diabetic patients as part of the Michigan Diabetes Research and Training Center (MDRTC). Use of an intelligent microcomputer to enter and retrieve the data and use of a relational database management system (DBMS) to store and manage data have provided a flexible, efficient method of achieving both support of small projects and monitoring overall activity of the Diabetes Center Unit (DCU). Simplicity of access to data, efficiency in providing data for unanticipated requests, ease of manipulations of relations, security and “logical data independence” were important factors in choosing a relational DBMS. The ability to interface with an interactive statistical program and a graphics program is a major advantage of this system. Out database currently provides support for the operation and analysis of several ongoing research projects.

Collector of process working data

Abstract: PURPOSE:To resolve the cause of an error at an early stage and to recover a system to the preceding non-error state of the system, by selectively collecting the execution career of each program and adding a means to regenerate the working state of program when an error is caused. CONSTITUTION:A basic processing part 1 of a processor of a computer that performs the extraction, decoding and execution of an instruction is connected to a main storage device 2 and a process working data collector 4 each. The working data fetching part 5 of the collector 4 fetches the data access information to extract the access timing with the part 1 gives an access to the device 2 in the form of an operand of the instruction plus the execution mode of the computer, and then feeds the access information to a process working data selecting part 6 along with a selection request signal. The part 6 checks the data access information based on the data access information plus the process working data selection information given from outside and selects the data which is supplied and delivered to and from the device 2 when the process is executed to feed the data to a process working data storing part 7. The part 7 assembles the selected information to store it and adds a means to regenerate the working state of the process.

A general semantic analyser for data base access

Abstract: The paper discusses the design principles and current status of a natural language front end for access to data bases. This Is based on the use, first, of a semantically-oriented question analyser exploiting general, language-wide semantic categories and patterns, rather than data base-specific ones; and, second, of a data base-oriented translation component for obtaining search specifications from the meaning representations for questions derived by the analyser. This approach is motivated by the desire to reduce the effort of providing data base-specific material for the front end, by the belief that a general analyser is well suited to the "casual" data base user, and by the assumption that the rich semantic apparatus used will be both adequate as a means of analysis and appropriate as a tool for linking the characterisations of input and data language items. The paper describes this approach in more detail, with emphasis on the existing, tested, analyser.

Programmed project management in pennsylvania: statewide data access (abridgment)

Abstract: One aspect of the Pennsylvania Department of Transportation's commitment to provide a vastly improved transportation program to the commonwealth is the implementation of responsible and practical management systems. One of these systems, the project management system (PMS), is making major contributions in the area of planning and scheduling the use of dwindling resources that must be used efficiently to maintain and restore an extremely large highway system. PMS is a computerized information management system that integrates project-related data from the engineering and planning communities with accounting data from the financial community. These data are stored in a common data base and are accessed by users located in the department's central office and the 11 engineering districts. PMS has enabled people in various branches of the department to obtain consistent information on all projects because everyone has access to the same data base. The project-related and accounting-related data maintained in PMS enable it to track the physical and fiscal progress of the projects on the department's program. PMS employs on-line updating to make changes in the project data. It also serves, therefore, as a powerful communications tool because a change made anywhere in the state is instantly available to all other system users. (Author)

Data transfer control system of multiprocessor system

Abstract: PURPOSE:To transmit data between one processor and another processor in the data access mode and transfer data between one processor and plural processors in the data copy mode, by using the common bus for the data access mode and the data copy mode divisionally CONSTITUTION:In data transfer in the copy mode, when processor 1a of the highest priority level is selected, all other processors 1b, 1c and 1d read data of common bus 4 simultaneously and write the read data to respective designated memory areas When this data transfer is completed, processor 1b of the next higher priority level is selected, and all processors 1a, 1b and 1d read the data of common bus 4 simultaneously Similar operations are performed after this; and when data transfer for all processors 1a-1d is completed, the mode is returned to the data access mode again

Paging as a "language processing" task

Abstract: This paper examines "language processing" approach to paging where the of the programming language compiler or interpreter is responsible for generating the necessary control code for the page management of a program. We explore this idea for APL and describe an approach to incorporating in a program the necessary paging functions. The semantics of APL computation are examined to observe how paging operations can be incorporated into the computation. We discuss a model of data access in APL that exhibits storage use for both scalar and page references. A data structure that encodes the logical use of data from an array is introduced. We find that ordering computations efficiently and computing paging needs can be determined by simple transformations on this structure. This analysis leads us to an efficient method for paging an APL computation. Our approach builds on previous studies for efficiently executing APL.

The Data Base Design Process

Abstract: The objective of data base design is to produce an integrated data base which is accurate and secure and which supports application systems in an efficient manner. Each of these characteristics—integration, integrity, security, and performance—must be addressed during the design process to assure the desired outcome. Integration is the result of specifying data base content and structure in response to the needs of more than one application area. Integrity is assured through controls on application systems that prevent data loss or improper modification. The use of procedures and dbms features that promote data sharing, while limiting access to data which are not shared, results in data base security. Finally, data base performance depends on both the efficiency of the physical realization of the data and the ability of the data base to satisfy processing requests in a timely manner.