ParVox is a distributed visualization system consisting of a rendering core running on a parallel computer and a graphic user interface program (GUI) running on a Unix...

Briefs: Physical Sciences
Properties of Ni/Zr Melts Related to Formability of Glasses

A report describes a study of the relationships between (1) the viscosities and specific volumes of Ni/Zr melts and (2) the formability of Ni/Zr-alloy metallic glasses. Experiments were performed on electrostatically levitated, radiantly heated molten specimens of two compound-forming...

Briefs: Photonics/Optics
Optical Diagnostics of High-Pressure Liquid Fuel Sprays

A report describes experiments in which nonintrusive optical diagnostic techniques were applied to high-pressure fuel sprays in simulated advanced turbine-engine combustor environments. The experiments involved three different fuel injectors in two unique optically accessible combustors: a...

Briefs: Software
Software Detects Small Satellites in Spacecraft Imagery

A computer program processes images acquired at different times by instrumentation aboard a spacecraft to detect small satellites of asteroids and other planetary bodies. The program coregisters the images, removes instrument artifacts and images of background stars, and performs a...

An effective Lewis number has been defined for two-fluid mixtures under conditions of (1) supercritical temperature and pressure and (2) large gradients of temperature and composition. The...

Polyimides have been used widely in fiber-reinforced composite materials for aerospace components and in thin films for packaging of electronic circuitry. Typically, the synthesis of a...

Wide-angle, open-faced retroreflectors of a proposed type would be constructed by use of traditional corner-cube reflectors as building blocks. Wide-angle retroreflectors are...

Briefs: Mechanical & Fluid Systems
Push/Pull Four-Point-Bending Apparatus

The figure depicts an improved apparatus for three- or four-point bending tests of stripe specimens. In a bending test, the specimen is subjected to tension along its top surface and compression along...

A mathematical model has been developed to predict the behavior of mutually interacting drops of a first fluid surrounded by a second fluid, under quiescent conditions at...

Briefs: Physical Sciences
On the Validity of Using Assumed PDFs in Modeling Two-Phase Mixing

A report describes an investigation of the validity of using statistical methods based on single-point probability density functions (PDFs) in mathematical modeling of mixing between a turbulently flowing carrier gas and the vapor from liquid drops suspended in the gas. The...

A method for making a flow visible in a plane and determining in-plane velocities involves the digitization and digital processing of a sequence of monochrome video images of...

A process that involves reaction bonding makes it possible to form strong joints, with tailorable thicknesses and compositions, between high-temperature-resistant structural parts...

Briefs: Software
Easy-to-Use Software for Planning and Scheduling

The Automated Planning and Scheduling Environment (ASPEN) version 2 computer program comprises a modular, reconfigurable software framework and collection of software components that can be used for automated planning and scheduling in a variety of applications. ASPEN can automatically generate...

Briefs: Mechanical & Fluid Systems
Using Genetic Algorithms in Spacecraft Vibration Control

Three software products are being developed to help satisfy the needs of NASA and of private industry for reconfigurable active control systems to suppress vibrations in Reusable Launch Vehicles (RLVs) and other structures. These potentially highly marketable products are the...

Briefs: Software
Recursive and Adjacency Algorithms for Ranking Hypotheses

A library of computer programs has been developed to solve the problem of parametric ranking of a set of hypotheses on the basis of incomplete and/or uncertain information. In general, the ranking must be learned by use of training examples in which one observes the values of random...

Briefs: Materials
Diffusing Hf and Si Into Aluminide Bond Coats for TBCs

A process for making superior diffusion platinum-aluminide bond coats for plasma-sprayed or physical-vapor-deposited thermal-barrier coats (TBCs) on superalloy substrates has been devised. The novel aspect of the process lies in the use of several relatively inexpensive pack diffusion steps...

Briefs: Electronics & Computers
Study of Mixed-Norm Controllers for Suppressing Vibrations

A report describes a study of nominal-performance (H2), robust-performance (μ-synthesis), and mixed H2/μ methods for designing fixed-order controllers applied to an active-tendon control system for suppressing seismic vibrations in a structure. The study involves...

Two techniques have been proposed (see figure) for controlling the buoyancies and thus the altitudes of robotic lifting balloons (aerobots) that would carry scientific instruments...

A mathematical model has been developed for analyzing the steady-state performances of vortex pyrolysis reactors used to convert particles of raw biomass materials (usually small wood chips)...

A rectangular-constellation-based blind-equalization (RECBEQ) technique implemented by a real-time, recursive algorithm has been developed to improve the performances of radio...

A mathematical model has been developed to predict the behavior of an isolated drop of a first fluid surrounded by a second fluid, under quiescent conditions at supercritical...

Briefs: Physical Sciences
Ultrasonic Profiling of an Object

A computer-controlled ultrasonic C-scan instrumentation system that was developed primarily for use in finding defects inside solid material specimens can also be used to obtain three-dimensional profiles...

Several microwave-cavity devices at various stages of development are designed for heating material samples or process streams with uniform temperature-versus-time histories. These devices...

An improved method of synthesis of crystalline tin monoxide (SnO) powder for use in anodes of lithium-ion electrochemical power cells has been developed. The carbon used in anodes...

An improved solvent-extraction/infrared-analysis technique has been devised to replace an older technique for measuring very small concentrations of nonvolatile residues of...

Zn4Sb3 has been identified as a high-performance thermoelectric material. In p-type, Zn4Sb3 samples have exhibited the greatest dimensionless...

Briefs: Electronics & Computers
Snapshot CCD Camera With Microelectromechanical Shutter

A proposed charge-coupled-device (CCD) camera would be mechanically shuttered by a planar array of micromachined, electromechanically actuated shutters. This proposal has arisen as part of the solution to the problem of designing a visible/near-infrared imaging spectrometer using a...

Wiping devices that exploit fingerlike bending motions produced by electroactive polymeric (ionomeric) actuators are undergoing development. These wiping devices function similarly to...

Spectrum would be utilized more efficiently than in CDMA and FDMA.

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