Keyword: Computer simulation

Briefs: Electronics & Computers
High-Power, High-Efficiency Ka-Band Space Traveling-Wave Tube

The L-3 Communications Model 999H traveling-wave tube (TWT) has been demonstrated to generate an output power of 144 W at 60-percent overall efficiency in continuous-wave operation over the frequency band from 31.8 to 32.3 GHz. The best TWT heretofore commercially available for...

Briefs: Mechanical & Fluid Systems
Staggering Inflation To Stabilize Attitude of a Solar Sail

A document presents computational simulation studies of a concept for stabilizing the attitude of a spacecraft during deployment of such structures as a solar sail or other structures supported by inflatable booms. Specifically, the solar sail considered in this paper is a square sail...

Briefs: Semiconductors & ICs

A research and development effort now underway is directed toward satisfying requirements for a new type of relatively inexpensive, lightweight, microwave antenna array and associated...

Briefs: Electronics & Computers

Hybrid deployable radio antennas and reflectors of a proposed type would feature rigid narrower apertures plus wider adjoining apertures comprising reflective surfaces supported by...

Briefs: Physical Sciences

Increasing the accuracy of storm-surge flood forecasts is essential for improving preparedness for hurricanes and other severe storms and, in particular, for optimizing...

Briefs: Information Technology

A method of sequence detection has been proposed to mitigate the effects of inter-slot interference and inter-symbol interference (both denoted "ISI") in the reception of M-ary...

Briefs: Electronics & Computers

The NASA Ames hyperwall is a display system designed to facilitate the visualization of sets of multivariate and multidimensional data like those generated in complex engineering and...

Briefs: Physical Sciences

A recently proposed boundary condition for atomistic computational modeling of semiconductor nanostructures (particularly, quantum dots) is an improved alternative to two prior...

Briefs: Information Technology

The spatial standard observer is a computational model that provides a measure of the visibility of a target in a uniform background image or of the visual discriminability of two images. Standard observers have...

Briefs: Information Technology

An alternative to an optimal method of automated classification of signals modulated with M-ary phase-shift-keying (M-ary PSK or MPSK) has been derived. The alternative method is approximate, but it...

Briefs: Software
Reconfigurable Software for Controlling Formation Flying

Software for a system to control the trajectories of multiple spacecraft flying in formation is being developed to reflect underlying concepts of (1) a decentralized approach to guidance and control and (2) reconfigurability of the control system, including reconfigurability of the...

Briefs: Software
Simulating Responses of Gravitational-Wave Instrumentation

Synthetic LISA is a computer program for simulating the responses of the instrumentation of the NASA/ESA Laser Interferometer Space Antenna (LISA) mission, the purpose of which is to detect and study gravitational waves. Synthetic LISA generates synthetic time series of the LISA...

Briefs: Software
Software for Simulating Air Traffic

Future Air Traffic Management Concepts Evaluation Tool (FACET) is a system of software for performing computational simulations for evaluating advanced concepts of advanced air-traffic management. FACET includes a program that generates a graphical user interface plus programs and databases that implement...

Briefs: Software

SAUSAGE (Still Another Utility for SAR Analysis that's General and Extensible) is a computer program for modeling (see figure) the performance of synthetic-aperture radar (SAR) or...

Briefs: Software

GeoFEST(P) is a computer program written for use in the QuakeSim project, which is devoted to development and improvement of means of computational simulation of earthquakes. GeoFEST(P)...

Briefs: Information Technology
Improved Solar-Radiation-Pressure Models for GPS Satellites

A report describes a series of computational models conceived as an improvement over prior models for determining effects of solar-radiation pressure on orbits of Global Positioning System (GPS) satellites. These models are based on fitting coefficients of Fourier functions of...

Briefs: Information Technology

Practical Simulator Network (PSimNet) is a set of data communication protocols designed especially for use in handling messages between computers that are engaging cooperatively in...

Briefs: Electronics & Computers

Resonant edge-slot (slotted-waveguide) array antennas can now be designed very accurately following a modern computational approach like that followed for some other microwave components....

Briefs: Software
DAVE-ML Utility Programs

DAVEtools is a set of Java archives (*.jar files) that embodies tools for manipulating flight-dynamics models that have been encoded in dynamic aerospace vehicle exchange markup language (DAVE-ML). [DAVE-ML is an application program, written in Extensible Markup Language (XML), for encoding complete computational models...

Briefs: Software
Simulation of Dropping of Cargo With Parachutes

Decelerator System Simulation (DSS) is a computer program for predicting and analyzing the dynamics of a load of cargo dropped with parachutes from an aircraft. A DSS simulation runs from the first motion in the aircraft until the payload reaches the ground. Intended for use in support of airdrop...

Briefs: Software
Updated Computational Model of Cosmic Rays Near Earth

An updated computational model of the galactic-cosmic-ray (GCR) environment in the vicinity of the Earth, Earth's Moon, and Mars has been developed, and updated software has been developed to implement the updated model. The GCR model and software in their original forms, developed during the...

Briefs: Mechanical & Fluid Systems
Using Plates To Represent Fillets in Finite-Element Modeling

A method that involves the use of fictitious plate elements denoted bridge plates has been developed for representing the stiffnesses of fillets in finiteelement calculations of deflections, stresses, and strains in structures. In the absence of this method, it would be necessary to...

Briefs: Medical

Cochlear implants have been used successfully to provide auditory information for bilaterally profoundly deaf patients. This is achieved by electrically...

Briefs: Electronics & Computers

A digital-signal- processing algorithm (somewhat arbitrarily) called “SUMPLE” has been devised as a means of aligning the outputs of multiple receiving radio antennas in a large...

Briefs: Software
Quantum Entanglement Molecular Absorption Spectrum Simulator

Quantum Entanglement Molecular Absorption Spectrum Simulator (QE-MASS) is a computer program for simulating twophoton molecular-absorption spectroscopy using quantum-entangled photons. More specifically, QE-MASS simulates the molecular absorption of two quantum-entangled photons...

Application Briefs: Robotics, Automation & Control

Stern Pinball of Melrose Park, IL, is the only manufacturer of coin-operated pinball machines in the world. Today, Stern’s pinball games are designed using...

Briefs: Semiconductors & ICs

The figure is a schematic diagram of a complementary metal oxide/semiconductor (CMOS) electronic circuit that performs one of three different logic functions, depending on the level of...

Briefs: Photonics/Optics
Using Quasiparticle Poisoning To Detect Photons

According to a proposal, a phenomenon associated with excitation of quasi- particles in certain superconducting quantum devices would be exploited as a means of detecting photons with exquisite sensitivity. The phenomenon could also be exploited to perform medium-resolution spectroscopy. The...

Briefs: Software
Simulating Humans as Integral Parts of Spacecraft Missions

The Collaborative-Virtual Environment Simulation Tool (C-VEST) software was developed for use in a NASA project entitled "3-D Interactive Digital Virtual Human." The project is oriented toward the use of a comprehensive suite of advanced software tools in computational simulations for...