Showing papers on "Data access published in 1979"

The data access and transfer support in a local heterogeneous network (HMINET)

Abstract: The following paper presents a local heterogeneous network, the HMINET. The adopted software architecture identifies a data access and transfer level. The higher level applications afford a mechanism for data access and transfer to alleviate the effects of the incompatibilities and the differences between the data management systems. The paper describes the major problems and design decisions we adopted for the Data Access and Transfer System (DATS).

Data storage and access apparatus

Abstract: Data storage and access apparatus for multi-dimensional data processing. The apparatus includes a storage shift register array (SSRA) to permit data storage and one or more storage/access shift register arrays (S/A SRA) to permit data storage and data access.

A constructive approach to reliable synchronization code

Abstract: This paper describes a new approach to developing reliable software for communication between parallel processes. The basis of this approach is the shared use of abstract data objects, and the separation of synchronization-related software from the software performing the actual data access. The paper presents a language in which synchronization behavior for abstract data objects can be specified independently of other kinds of behavior. Specifications written in this language can be used as a basis for constructing the required synchronization software automatically. Also discussed is the use of such specifications in verifying properties of programs which make use of the abstract objects for interprocess communication.

Information retrieval with APL by adaptive index and user guidance

Abstract: A system is described applicable for information retrieval and update both in formatted and unformatted files containing non-numerical data. It uses a new reference-string indexing technique which supports partial-match queries and similar-record search. The reference-string index is adapted to data usage or data. Those parts of records which are estimated by the program to be specified very often in queries are included as reference strings and inverted. For data access in the retrieval phase, the specified attribute values and their logical expressions are transformed into a logical expression between reference strings. Primary and secondary (index) data are stored as external files using auxiliary processors for access. The retrieval and update functions are combined with the user-guidance component used to describe data (dictionary), to teach system use, and to assist as a permanently available Help feature. As an internal structure it uses a semantic net to navigate the user from general to more specific information. A new interesting feature is the use of selected reference strings and selected combinations of them as a more detailed data description extracted automatically from the data or even data usage.

An experimental evaluation of data abstraction

Abstract: An experiment was conducted to evaluate the use of data abstraction and to assess its effects on program modification. Programs developed using data-abstraction were found to be substantially larger than equivalent programs developed without it, and the larger abstract-data programs were more difficult to modify. No significant differences in programming error rates were found between programs with or without abstract datatypes. A subtle violation of one of data abstraction's primary objectives, hiding data representation details, was observed. Programmers showed a strong tendency to include application-specific processing within procedures given data access privileges.

Scotch and Sodas: Semantically Oriented Data Access and Storage for a Medical Record DBMS

Abstract: This paper describes current research directed toward a system that will allow health professionals simplified access to patient medical data for patient care and clinical research. A prototype medical record database management system has been implemented for a large database of patient records collected at an HMO. A menu-selection technique is used by the health professional for question-type specification, and natural language phrases involving medical terminology are used for specification of selection criteria. The data is semantically structured and encoded in an attempt to provide comprehensive and efficient retrieval of relevant information. A sample system interaction is described.