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At least 919 records · Page 51

IRDS prototyping with applications to the representation of EA/RA models

The requirements and system overview for the Information Resources Dictionary System (IRDS) are described. A formal design specification for a scaled down IRDS implementation compatible with the proposed FIPS IRDS standard is contained. The major design objectives for this IRDS will include a menu driven user interface, implementation of basic IRDS operations, and PC compatibility. The IRDS was implemented using Smalltalk/5 object oriented programming system and an ATT 6300 personal computer running under MS-DOS 3.1. The difficulties encountered in using Smalltalk are discussed.

Lekkos, Anthony A.↗

Prototype of a magnetically suspended flywheel energy storage system

The authors describe recent progress in the development of a 500-Wh magnetically suspended flywheel stack energy storage system. The design of the system and a critical study of the noncontacting displacement transducers and their placement in the stack system are discussed. The storage system has been designed and constructed and is currently undergoing experimental analysis. The results acquired from the noncontacting displacement transducer study show that currently available transducers will not function as desired and that further research is essential.

Plant, David P.↗

Expanding the domain of a prototype expert system with an eye on future maintenance - The FIESTA case study

The methods by which an expert system architecture can support such key elements of domain expansion and maintenance as knowledge acquisition, representation, addition, and modification, are presently illustrated by the Fault Isolation Expert System for TDRSS Applications (FIESTA). FIESTA highlights such similarities between conventional software engineering and expert system development as the benefits that accrue to loose coupling, modularity, and documentation. A major difference, however, is the set of opportunities afforded automated end-user maintenance by expert system technology.

Happell, Nadine↗

A prototype autonomous agent for crew and equipment retrieval in space

The ground-based demonstration of Extra Vehicular Activity (EVA) Retriever, a voice-supervised, intelligent, free-flying robot, is designed to evaluate the capability to retrieve objects (astronauts, equipment, and tools) which have accidentally separated from the Space Station. The EVA Retriever software is required to autonomously plan and execute a target rendezvous, grapple, and return to base while avoiding stationary and moving obstacles. The software architecture incorporates a hierarchical decomposition of the control system that is horizontally partitioned into five major functional subsystems: perception, world model, reasoning, sensing, and acting. The design provides for supervised autonomy as the primary mode of operation with teleoperation as the backup mode. It is intended to be an evolutionary system improving in capability over time and as it earns crew trust through reliable operation.

Erickson, J. D.↗

Optical depth of molecular gas in starburst galaxies - Is M82 the prototype?

An attempt is made to survey the CO(2-1) emission toward the centers of 17 IR-luminous galaxies which have previously been detected in CO(1-0). These galaxies span a wide range of size and L(FIR)/L(B) ratio, many have multiple-wavelength studies establishing them as starbursts, and some bear a morphological resemblance to M 82. Nine galaxies are detected and useful upper limits are placed on the remaining eight. Using the CO(2-1)/CO(1-0) ratio of antenna temperature as a diagnostic of optical depth, it is found that all of the galaxies contain predominantly optically thick molecular gas. This implies that the phase of starburst during which the molecular gas is optically thin, currently witnessed in M 82, is either uncommon or short-lived.

Verter, F.↗

AdaNET phase 0 support for the AdaNET Dynamic Software Inventory (DSI) management system prototype. Catalog of available reusable software components

The Ada Software Repository is a public-domain collection of Ada software and information. The Ada Software Repository is one of several repositories located on the SIMTEL20 Defense Data Network host computer at White Sands Missile Range, and available to any host computer on the network since 26 November 1984. This repository provides a free source for Ada programs and information. The Ada Software Repository is divided into several subdirectories. These directories are organized by topic, and their names and a brief overview of their topics are contained. The Ada Software Repository on SIMTEL20 serves two basic roles: to promote the exchange and use (reusability) of Ada programs and tools (including components) and to promote Ada education.

Hanley, Lionel↗

A demonstration of CMOS VLSI circuit prototyping in support of the site facility using the 1.2 micron standard cell library developed by National Security Agency

Two silicon CMOS application specific integrated circuits (ASICs), a data generation chip, and a data checker chip were designed. The conversion of the data generator circuitry into a pair of CMOS ASIC chips using the 1.2 micron standard cell library is documented. The logic design of the data checker is discussed. The functions of the control circuitry is described. An accurate estimate of timing relationships is essential to make sure that the logic design performs correctly under practical conditions. Timing and delay information are examined.

Smith, Edwyn D.↗

Prototyping distributed simulation networks

Durra is a declarative language designed to support application-level programming. The use of Durra is illustrated to describe a simple distributed application: a simulation of a collection of networked vehicle simulators. It is shown how the language is used to describe the application, its components and structure, and how the runtime executive provides for the execution of the application.

Doubleday, Dennis L.↗

Software technology testbed softpanel prototype

The following subject areas are covered: analysis of using Ada for the development of real-time control systems for the Space Station; analysis of the functionality of the Application Generator; analysis of the User Support Environment criteria; analysis of the SSE tools and procedures which are to be used for the development of ground/flight software for the Space Station; analysis if the CBATS tutorial (an Ada tutorial package); analysis of Interleaf; analysis of the Integration, Test and Verification process of the Space Station; analysis of the DMS on-orbit flight architecture; analysis of the simulation architecture.

Source record↗

Deployment and testing of a second prototype expandable surgical chamber in microgravity

During microgravity exposure, two separate expandable surgical chambers were tested. Both chambers had been modified to fit the microgravity work station without extending over the sides of the table. Both chambers were attached to a portable laminar flow generator which served two purposes: to keep the chambers expanded during use; and to provide an operative area environment free of contamination. During the tests, the chambers were placed on various parts of a total body moulage to simulate management of several types of trauma. The tests consisted of cleansing contusions, debridement of burns, and suturing of lacerations. Also, indigo carmine dye was deliberately injected into the chamber during the tests to determine the ease of cleansing the chamber walls after contamination by escaping fluids. Upon completion of the tests, the expandable surgical chambers were deflated, folded, and placed in a flattened state back into their original containers for storage and later disposal. Results are briefly discussed.

Markham, Sanford M.↗

Prototyping a large-scale distributed system for the Great Observatories era - NASA Astrophysics Data System (ADS)

The NASA Astrophysics Data System (ADS) is a distributed information system intended to support research in the Great Observatories era, to simplify access to data, and to enable simultaneous analyses of multispectral data sets. Here, the user agent and interface, its functions, and system components are examined, and the system architecture and infrastructure is addressed. The present status of the system and related future activities are examined.

Shames, Peter↗

Supernova 1987 A - Prototype of low metallicity type III supernovae or peculiar exception?

New stellar evolution calculations for the SN 1987 A progenitor, including a small but appropriate amount of semiconvection and mixing induced by differential rotation, yield good agreement with many observational constraints, as the HRD position of the progenitor star, a previous red supergiant phase, and CNO surface abundances close to the values obtained with the IUE satellite. The HRD track and surface abundances in different evolutionary stages are found to reflect many general properties of massive stars in the LMC. The results indicate that the SN 1987 A progenitor may have been an average massive star in the LMC, and that blue supergiants may be common SN II progenitors in low metallicity galaxies.

Langer, N.↗

Prototype FAGE determination of NO2

A low pressure laser-excited-fluorescence technique for the direct determination of atmospheric NO2 has been developed. Using a frequency-doubled Nd-YAG pump laser and a signal collection time of 20 s (10 s each signal and background), a detection limit of 450 pptv is calculated under laboratory conditions. Improved sensitivities will be possible with a higher repetition rate laser and lower fluorescence cell pressures.

George, L. A.↗

The mini-dome Fresnel lens photovoltaic concentrator array - Current status of component and prototype panel testing

NASA Lewis and ENTECH have been developing a high-efficiency, lightweight space photovoltaic concentrator array. The emphasis of the program has shifted to fabrication and testing of the minidome Fresnel lens and other array components. Protototype lenses have been tested for optical efficiency, with results around 90 percent, and tracking error performance. The results of these tests have been very consistent with the predicted analytical performance. Work has also progressed in the fabrication of the array support structure. Recent advances in 30 percent efficient stacked cell technology will have a significant effect on the array performance. It is concluded that near-term array performance goals of 300 W/sq m and 100 W/kg are feasible.

Piszczor, M. F.↗

SHARP: Spacecraft Health Automated Reasoning Prototype

The planetary spacecraft mission OPS as applied to SHARP is studied. Knowledge systems involved in this study are detailed. SHARP development task and Voyager telecom link analysis were examined. It was concluded that artificial intelligence has a proven capability to deliver useful functions in a real time space flight operations environment. SHARP has precipitated major change in acceptance of automation at JPL. The potential payoff from automation using AI is substantial. SHARP, and other AI technology is being transferred into systems in development including mission operations automation, science data systems, and infrastructure applications.

Atkinson, David J.↗

JPL space station telerobotic engineering prototype development: Advanced telerobotics system technology

The objective of the Advanced Telerobotics System Technology Task is to develop/prototype advanced telerobotics supervisory and shared control to enhance Intra-Vehicular Activity (IVA) teleoperation in the Space Station. The technology provides enhanced telerobotics capabilities while operating within the expected constraints of computation limitations, time delay, and bus bandwidth. A local site operator interface has also been developed for specifying teleoperation and shared control modes as well as supervised autonomous macros for execution at the remote site. The primary objective of the task is to transfer the advanced technology to appropriate flight centers to enhance the baseline Station capabilities.

Backes, Paul G.↗

JPL space station telerobotic engineering prototype development FY 91 status/achievements

The topics covered are presented in view graph form and include: (1) streamlining intravehicular activity (IVA) teleoperation activities on the Space Station Freedom (SSF); (2) enhancing SSF utilization during the man-tended phase; (3) telerobotic ground remote operations (TGRO); and (4) advanced telerobotics system technology (shared control).

Zimmerman, Wayne↗