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Meyer, D.

Publications and source records attributed to Meyer, D..

26 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2002

X2000 advanced avionics characterization study : Living in the modern world of difficult to predict processor performance

The characterization study has shown that adjustments in an application's data accesses can easily create a performance difference of three or more times in actual applications. In general, by iterating over a small portion of a data set rather than its entirety, execution can remain within cache thereby producing a performance increase. Additionally, the approaches used in performing I/O can make a major performance difference.

X2000 advanced avionics project↗
NASA NTRS1992

National Launch System cycle 1 loads and models data book

This document contains preliminary cycle 1 loads for the National Launch System (NLS) 1 and 2 vehicles. The loads provided and recommended as design loads represent the maximum load expected during prelaunch and flight regimes, i.e., limit loads, except that propellant tank ullage pressure has not been included. Ullage pressure should be added to the loads book values for cases where the addition results in higher loads. The loads must be multiplied by the appropriate factors of safety to determine the ultimate loads for which the structure must be capable.

Bugg, F.↗
NASA NTRS1990

Post-launch operations and data production

Postlaunch operations scheduled in connection with the October 5, 1990, launch of Space Shuttle Discovery with the Ulysses payload are detailed. A summary is presented of postlaunch events up to and including the separation of Ulysses from Discovery, providing a timeline for the upper-stage burn and spacecraft separation. A timeline is also provided for the payload switch-on. Initial in-orbit and routine operations are discussed and missions-operations organization, the data ground segment, and Ulysses data production are considered.

Beech, P.↗
NASA NTRS1988

Requirements for an EOS-oriented workstation

The determination of functional and performance requirements of a workstation specifically directed toward scientific users of the proposed NASA Earth Observing System information system is discussed. Image processing, user interface; data product visualization; and text processing are considered.

Kober, W.↗
NASA NTRS1987

Electron-spin-resonance studies of vapor-grown carbon fibers

The effects of annealing temperature and fiber diameter on the degree of disorder of vapor-grown carbon fibers were investigated by analyzing the electron-spin-resonance (ESR) line shapes of fibers annealed at six various temperatures up to 3375 K. The diameter of fibers, grown from methane gas, ranged from 10 to 140 microns with most fibers between 20 and 50 microns. It was found that the degree of disorder of vapor-grown fibers decreases upon annealing to higher temperature; standard angular deviation between the fiber axis and the crystallite basal planes could vary from 35 deg (for annealing temperature of 2275 K) to 12 deg (for 3375 K). With respect to fiber diameter, order parameters were found to be higher for fibers of smaller diameters.

Marshik, B.↗
NASA NTRS1985

Flowcharting with D-charts

A D-Chart is a style of flowchart using control symbols highly appropriate to modern structured programming languages. The intent of a D-Chart is to provide a clear and concise one-for-one mapping of control symbols to high-level language constructs for purposes of design and documentation. The notation lends itself to both high-level and code-level algorithmic description. The various issues that may arise when representing, in D-Chart style, algorithms expressed in the more popular high-level languages are addressed. In particular, the peculiarities of mapping control constructs for Ada, PASCAL, FORTRAN 77, C, PL/I, Jovial J73, HAL/S, and Algol are discussed.

Meyer, D.↗