Keyword: Computer simulation

Briefs: Information Technology

A method of automated computational fluid dynamics (CFD) has been invented for the generation of performance tables for an object subject to fluid flow. The method is applicable to...

Briefs: Information Technology
Improved Model of a Mercury Ring Damper

A short document discusses the general problem of mathematical modeling of the three-dimensional rotational dynamics of rigid bodies and of the use of Euler parameters to eliminate the singularities occasioned by the use of Euler angles in such modeling. The document goes on to characterize a Hamiltonian...

Briefs: Semiconductors & ICs

Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as...

Briefs: Semiconductors & ICs

Closely following the development reported in the article, "Low-Noise MMIC Amplifiers for 120 to 180 GHz" (NPO-42783), three new monolithic microwave integrated circuit (MMIC)...

Briefs: Physical Sciences

The multi-cone model is a computational model for estimating ionospheric delays of Global Positioning System (GPS) signals. It is a direct descendant of the conical-domain model, which...

Briefs: Materials

Devices that could be characterized as acoustically driven molecular sieves have been proposed for filtering water to remove all biological contaminants and all molecules larger...

Briefs: Electronics & Computers

A two-stage variable sample-rate conversion (SRC) system has been proposed as part of a digital signal-processing system in a digital communication radio receiver that utilizes a variety of...

Briefs: Software
DSN Simulator

The DSN Simulator (wherein “DSN” signifies NASA’s Deep Space Network) is an updated version of the software described in “DSN Array Simulator” (NPO-44506), Software Tech Briefs (Special supplement to NASA Tech Briefs), Vol. 32, No. 9 (September 2008), page 26. To recapitulate: This software is used for computational...

Briefs: Software

The conical-domain model is a computational model, now undergoing development, for estimating ionospheric delays of Global Positioning System (GPS) signals. Relative to the standard...

Briefs: Software

IceVal DatAssistant is software (see figure) that provides an automated, interactive solution for the management of data from research on aircraft icing. This software consists primarily of (1)...

Briefs: Software

In a proposed coding-and-modulation/ demodulation-and-decoding scheme for a free-space optical communication system, an error-correcting code of the low-density parity-check (LDPC) type would...

Application Briefs: Electronics & Computers

A lot has been written about Moore's Law and the potential limitations of semiconductor design and manufacturing in the future. Can we really continue to double the...

Articles: Medical

Kristina Irsch Wilmer Ophthalmological Institute, Johns Hopkins University
School of Medicine
Baltimore, MD

Amblyopia, commonly known as “lazy eye,” is the leading cause of vision loss in...

Briefs: Information Technology
Presentation Extensions of the SOAP

A set of extensions of the Satellite Orbit Analysis Program (SOAP) enables simultaneous and/or sequential presentation of information from multiple sources. SOAP is used in the aerospace community as a means of collaborative visualization and analysis of data on planned spacecraft missions. The following...

Application Briefs: Electronics & Computers
SGI® Altix® ICE system
Silicon Graphics, Inc. (SGI)
Sunnyvale, CA
800-800-7441
www.sgi.com

SGI has supplied NASA's Advanced Supercomputing facility at NASA Ames...

Application Briefs: Test & Measurement
Surface and roundness measurement systems
Taylor Hobson
West Chicago, IL
630-621-3099
www.taylor-hobson.com

NASA’s Marshall Space Flight...

Eye on Innovation: Software

When it comes to testing products for long-term durability, shock exposure survival, or accelerated life testing, the classic technique most engineers turn to is vibration testing with a...

Briefs: Photonics/Optics
Formation Flying of Components of a Large Space Telescope

A conceptual space telescope having an aperture tens of meters wide and a focal length of hundreds of meters would be implemented as a group of six separate optical modules flying in formation: a primary-membrane-mirror module, a relay-mirror module, a focal-plane-assembly module...

Briefs: Electronics & Computers
Wide-Band Radar for Measuring Thickness of Sea Ice

A wide-band penetrating radar system for measuring the thickness of sea ice is under development. The need for this or a similar system arises as follows: Spatial and temporal variations in the thickness of sea ice are important indicators of heat fluxes between the ocean and atmosphere and,...

Briefs: Mechanical & Fluid Systems
Improved Thermal Design of a Compression Mold

A compression tool used to make 1-in. (2.5-cm) diameter disks of high-temperature polymers was designed to be shorter and of larger diameter than conventional tools to reduce heat loss to the surrounding air, thus making more efficient use of applied heat. This system is less sensitive to the amount...

Articles: Software

In our annual poll of executives at leading analysis and simulation software companies, we posed questions dealing with virtual prototyping, multiphysics, the roles of the designer and analyst,...

Briefs: Photonics/Optics

Progress has been made toward solving some practical problems in the implementation of terahertz-to-optical frequency converters utilizing whispering-gallery-mode (WGM) resonators....

Briefs: Electronics & Computers

A method of utilizing information available in the constraints imposed by a low-density parity-check (LDPC) code has been proposed as a means of aiding the recovery of symbol...

Briefs: Information Technology
Providing Internet Access to High-Resolution Mars Images

The OnMars server is a computer program that provides Internet access to high-resolution Mars images, maps, and elevation data, all suitable for use in geographical information system (GIS) software for generating images, maps, and computational models of Mars. The OnMars server is an...

Briefs: Information Technology
Providing Internet Access to High-Resolution Lunar Images

The OnMoon server is a computer program that provides Internet access to high-resolution Lunar images, maps, and elevation data, all suitable for use in geographical information system (GIS) software for generating images, maps, and computational models of the Moon. The OnMoon server...

Briefs: Information Technology
Virtual Satellite

Virtual Satellite (VirtualSat) is a computer program that creates an environment that facilitates the development, verification, and validation of flight software for a single spacecraft or for multiple spacecraft flying in formation. In this environment, enhanced functionality and autonomy of navigation, guidance, and control...

Briefs: Physical Sciences
On-Orbit Multi-Field Wavefront Control With a Kalman Filter

A document describes a multi-field wavefront control (WFC) procedure for the James Webb Space Telescope (JWST) on-orbit optical telescope element (OTE) fine-phasing using wavefront measurements at the NIRCam pupil. The control is applied to JWST primary mirror (PM) segments and...

Briefs: Physical Sciences

A method of simplified computational modeling of oxidation of hydrocarbons is undergoing development. This is one of several developments needed to enable accurate computational simulation of...

Briefs: Software
Toward Better Modeling of Supercritical Turbulent Mixing

A study was done as part of an effort to develop computational models representing turbulent mixing under thermodynamic supercritical (here, high pressure) conditions. The question was whether the large-eddy simulation (LES) approach, developed previously for atmospheric-pressure...