Showing papers on "Data access published in 1982"

Microprocessor Assisted Tuple Access, Decompression and Assembly for Statistical Database Systems

Abstract: A methodology is formulated for determining if a microprocessor-based specialized system is practical for the solution of a problem in an application. This methodology is followed in the description and justification of of a back-end system for use with a statistical database system. The functions to be performed by the back-end system include those related to attribute partitioning, compression, and data access. It is shown that the system designed (the Microprocessor Assist System) will be costeffective in increasing the performance of a statistical data management system.

A data processing network having a distributed data file access control

Abstract: Dynamic replication of data under distributed system control to control the utilization of resources in a multiprocessing, distributed data base system avoiding a central node maintained control, or synchronization by immediately conforming all copies of an updated data file, is achieved by a distributed access control of peer elements by which, 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 (10, 12, 14) and utilizing a status and control table (in SAC 60, 62, 64) at each node which describes that node's view of the status for shared data items at other nodes. Access, including copying and deletion permission, is granted, when a search of the local table discloses no conflict. If conflict is disclosed, messages are exchanged with all involved nodes until the local table discloses no conflict.

Database systems: Human factors in data access

Abstract: Database users make choices, form queries, and understand output. Good computer systems must accommodate the ways that humans best accomplish such tasks. Here we review relevant facts and principles from experimental studies of human information processing. We discuss known characteristics of human memory, language use, and problem solving, and suggest ways in which such knowledge can be applied to the design of systems that will render better service.

Optimal Performance of Inverted Files

Abstract: Many managerial users of information systems require access to data based upon nonunique data record qualifications or classifications. A class of computer file organizations, called inverted files, has been devised to efficiently support such data retrieval. Fundamental to the use of such a file or database organization is the selection of data elements or keys for creation of nonunique key indexes. These indexes provide rapid access to data records which are qualified by logical key expressions. This paper formulates this selection problem as a zero-one, nonlinear programming problem with constraints and describes an optimization algorithm. The model recognizes both known and ad hoc uses of data; complex, Boolean key queries; and index storage capacity and query response time constraints. Computational experience is similar to previous algorithms, which consider more restricted problem formulations.

Characteristics Of A Protocol For Exchanging Digital Image Information

Abstract: This paper will discuss requirements for a protocol for exchanging digital image information between users of possibly dissimilar equipment. The need for simplicity, flexibility and ease of data access will be outlined and several examples will be presented which illustrate how practical issues such as data block sizes and hardware compatibility impact these requirements. An additional requirement for users who must exchange physical media, perhaps on a one time basis through the mail, is that the data format contain sufficient descriptive information so the data may be utilized without reference to a published document. A companion paper describes one implementation of a standard magnetic tape format which meets these requirements.

Data Base Model for Distribution Facilities

Abstract: In this paper we describe an electric facilities data base model which: - Provides data for engineering analysis, accounting and map production. - provides efficient access to data by electric network or by area. - has been implemented at several utilities. The model presented in this paper in incorporated in two IBM programs: Interactive Geo-Facilities Graphic Support (IGGS) and Geo-Facility Data Base Support (GDBS). The programs - provide for the storage of geographic and alphanumeric information, including electric facilities and land features. - support selective updating and display of both the geographic and alphanumeric data using an interactive workstation.

Numerical database management system: a model

Abstract: Numerical databases arise in many scientific applications to keep track of large sparse and dense matrices. Unlike the many matrix data storage techniques available for incore manipulation, very large matrices are currently limited to a few compact storage schemes on secondary devices, due to the complex underlying data management facilities. This paper presents a model of an approach to numerical database management system that provides generalized facility for promoting physical data independence by relieving users from the need for knowledge of the physical data organization on the secondary devices.Each of the storage techniques for dense and sparse matrices is described by a physical schema and the tools for any numerical database description, mapping to storage and data access are provided by data language facilities. The feasibility of the model with regard to our prototype implementation of a generalized numerical database translator is also discussed.

Transportable natural-language interfaces: problems and techniques

Abstract: I will address the questions posed to the panel from wlthln the context of a project at SRI, TEAM [Grosz, 1982b], that is developing techniques for transportable natural-language interfaces. The goal of transportability is to enable nonspeciallsts to adapt a natural-language processing system for access to an existing conventional database. TEAM is designed to interact with two different kinds of users. During an acquisition dlalogue, a database expert (DBE) provides TEAM with information about the files and fields in the conventlonal database for which a natural-language interface is desired. (Typlcally this database already exists and is populated, but TEAM also provides facillties for creating small local databases.) This dlalogue results in extension of the language-processlng and data access components that make it possible for an end user to query the new database in natural language.

Graphic interaction with database systems

Abstract: Easy access to data “hidden” in a database is a prerequisite of a good interactive Computer Aided Design (CAD) program that relies on that data. Moreover, access must be seen to be easy by users of programs who have no prior experience of computing. A method of extracting and inserting data into a database is outlined, that allows the user to identify areas of interest simply by pointing at a graphical display. The system is known as QUEST (QUEry Stored Text) and forms part of a suite of programs for recording and retrieving information describing existing building stock. These applications elucidate results of research on user interfaces, graphics and data management systems at EdCAAD.

Control system of external storage device

Abstract: PURPOSE:To perform an data access with a high speed without giving an access to an undesired recording track, by storing a data block index tree data in the 1st storage device and at the same time storing a continuous and regular data access index data in the 2nd storage device respectively. CONSTITUTION:An instruction of an upper device is decoded through a control part 3 to control a track access control circuit 6, and a head 8 is positioned at the recording position of an optical disk 9 according to the contents of the 2nd or 1st storage device 2 or 1. When the head 8 is positioned at the continuous and regular data recording position, the access time is short each time to the disk 9 to increase the effect of the increment of other queuing time. To avoid this, the index data of the device 2 is used. When a data which is neither continuous nor regular is read, the head 8 is positioned on the track of the disk 9 by means of the index data of the device 1. Then the data is sent to an upper device through an interface circuit 4.

The Database System Simulator (DBSS): Data description and data access capabilities

Abstract: This paper presents a simulation sublanguage specifically attuned to the needs of database designers and analysts. This language consists of: (a) facilities for representing logical data structures and for mapping these onto an address space, and (b) data access commands which use these data structure facilities to simulate database traversal. Both the data structure facilities and the data access commands are patterned after the CODASYL data model, a widely known model for which many implementations exist. This paper illustrates the use of the DBSS commands with examples and explains their effect on the internal structure of the supporting facilities.

Information processing equipment

Abstract: PURPOSE:To handle a control data of a memory properly, by converting a data by a conversion or reverse conversion table in accordance with an address pointer access instruction, in a composite computer system. CONSTITUTION:When processors 111, 112 of processor modules 101, 102 transmits the discrimination between a data access instruction and an address pointer access instruction, to address conversion coupling devices 131, 132, the address point access instruction is received, and when the instruction is a read instruction, a read data by said instruction is converted by an address reverse conversion table, and in case the instruction is a write instruction, a write data is converted and controlled by an address conversion table. Accordingly, a control data of a memory is handled properly even by a processor on a different processor module.

Extended-address generator

Abstract: PURPOSE:To generate extended-address data by decreasing the amount of information in an address table, by adding CPU address data and another address data generated by the address table digitally within the specific range of the address data of a CPU. CONSTITUTION:Address data, consisting of n' bits is supplied from a CPU to the terminal 1 of an extended-address generator to obtain L-bit extended-address data at a terminal 4. This generator is provided with an adder 5, and l'-bit address table data supplied from an address table via terminals 2 and 3 and another address data from the CPU are added together digitally to output extended-address data from the terminal 4. The number m' of data couples in the address table used for extension is used for both instruction access and data access, and some or all of address data from the CPU are supplied to specific address detector 8 to switch gate circuits 6 and 7 for corresponding spaces.

Test set for computer peripheral coupling unit - uses microprocessor with ROM and RAM and validation circuit sequentially comparing ROM data with peripheral output

Abstract: The system utilises a simulator including a microprocessor with program and dynamic memories communicates using a bus with an interface control circuit. The interface receives data transmitted by the connecting unit under test and controls access to data contained in a data memory by use of a data access circuit. A logic validation circuit receives data from the data access circuit and also data to be written in to the peripheral unit, as provided by the connecting unit. The validation circuit sequentially compares the data to signal if an error is present. The validation circuit calculates the check signals using data contained in the data memory. This contains data and addresses to simulate partic. peripheral equipments including their mechanical and electromechanical characteristics.