12 research outputs found
System configuration and executive requirements specifications for reusable shuttle and space station/base
System configuration and executive requirements specifications for reusable shuttle and space station/bas
SIMULATION OF A MULTIPROCESSOR COMPUTER SYSTEM
The introduction of computers and software engineering in telephone
switching systems has dictated the need for powerful design aids
for such complex systems. Among these design aids simulators -
real-time environment simulators and flat-level simulators - have
been found particularly useful in stored program controlled switching
systems design and evaluation. However, both types of simulators
suffer from certain disadvantages.
An alternative methodology to the simulation of stored program
controlled switching systems is proposed in this research. The
methodology is based on the development of a process-based multilevel
hierarchically structured software simulator. This methodology
eliminates the disadvantages of environment and flat-level simulators.
It enables the modelling of the system in a 1 to 1 transformation
process retaining the sub-systems interfaces and, hence, making it
easier to see the resemblance between the model and modelled system
and to incorporate design modifications and/or additions in the
simulator.
This methodology has been applied in building a simulation package
for the System X family of exchanges. The Processor Utility Sub-system
used to control the exchanges is first simulated, verified and validated.
The application sub-systems models are then added one level higher_,
resulting in an open-ended simulator having sub-systems models at
different levels of detail and capable of simulating any member of the
System X family of exchanges. The viability of the methodology is
demonstrated by conducting experiments to tune the real-time operating
system and by simulating a particular exchange - The Digital Main
Network Switching Centre - in order to determine its performance
characteristics.The General Electric Company Ltd,
GEC Hirst Research Cent,
Wemble
Software test and evaluation study phase I and II : survey and analysis
Issued as Final report, Project no. G-36-661 (continues G-36-636; includes A-2568
FBI fingerprint identification automation study. AIDS 3 evaluation report. Volume 3: Operational feasibility
An evaluation is presented which is defined as the adequacy of system design with known functional and performance requirements. The proposed Rockwell International AIDS 3 card, document and data flow are presented to summarize the concepts involved and the relationships between functions. The analysis and evaluation includes a study of system capability, processing rates, search requirements and response accuracy as well as a consideration of operational components and hardware integration. Results indicate that the AIDS 3 System concept is operationally feasible if production capacity is slightly enhanced but that operational complexity, hardware integration and a lack of conceptual data pertinent to some of the functions are areas of concern
Data bases and data base systems related to NASA's aerospace program. A bibliography with indexes
This bibliography lists 1778 reports, articles, and other documents introduced into the NASA scientific and technical information system, 1975 through 1980
Earth resources technology satellite. Volume 14 - Ground data handling system design
NASA Ground Data Handling system design for ERT
Performance of Computer Systems; Proceedings of the 4th International Symposium on Modelling and Performance Evaluation of Computer Systems, Vienna, Austria, February 6-8, 1979
These proceedings are a collection of contributions to computer system performance, selected by the usual refereeing process from papers submitted to the symposium, as well as a few invited papers representing significant novel contributions made during the last year. They represent the thrust and vitality of the subject as well as its capacity to identify important basic problems and major application areas. The main methodological problems appear in the underlying queueing theoretic aspects, in the deterministic analysis of waiting time phenomena, in workload characterization and representation, in the algorithmic aspects of model processing, and in the analysis of measurement data. Major areas for applications are computer architectures, data bases, computer networks, and capacity planning.
The international importance of the area of computer system performance was well reflected at the symposium by participants from 19 countries. The mixture of participants was also evident in the institutions which they represented: 35% from universities, 25% from governmental research organizations, but also 30% from industry and 10% from non-research government bodies. This proves that the area is reaching a stage of maturity where it can contribute directly to progress in practical problems
Fourth NASA Goddard Conference on Mass Storage Systems and Technologies
This report contains copies of all those technical papers received in time for publication just prior to the Fourth Goddard Conference on Mass Storage and Technologies, held March 28-30, 1995, at the University of Maryland, University College Conference Center, in College Park, Maryland. This series of conferences continues to serve as a unique medium for the exchange of information on topics relating to the ingestion and management of substantial amounts of data and the attendant problems involved. This year's discussion topics include new storage technology, stability of recorded media, performance studies, storage system solutions, the National Information infrastructure (Infobahn), the future for storage technology, and lessons learned from various projects. There also will be an update on the IEEE Mass Storage System Reference Model Version 5, on which the final vote was taken in July 1994
The Multispectral Imaging Science Working Group. Volume 3: Appendices
The status and technology requirements for using multispectral sensor imagery in geographic, hydrologic, and geologic applications are examined. Critical issues in image and information science are identified