Briefs: Physical Sciences
Real-Gas Effects on Binary Mixing Layers

This paper presents a computational study of real-gas effects on the mean flow and temporal stability of heptane/ nitrogen and oxygen/ hydrogen mixing layers at supercritical pressures. These layers consist of two counter- flowing free streams of different composition, temperature, and density. As in...

Briefs: Physical Sciences

Conventional commercial spectrometers or spectrophotometers are usually able to measure optical spectrum from a specified surface area at one...

Briefs: Physical Sciences
Reconditioned Test Equipment as a Key Driver in Reducing Life Cycle Support Costs

Previously owned test and measurement equipment has been purchased for over 50 years by the United States military, agencies of the Federal gov- ernment, and prime contractors that support these organizations. Yet, despite the significant amount of previously owned...

Briefs: Physical Sciences
Wedge Heat-Flux Indicators for Flash Thermography

Wedge indicators have been proposed for measuring thermal radiation that impinges on specimens illuminated by flash lamps for thermographic inspection. Heat fluxes measured by use of these indicators would be used, along with known thermal, radiative, and geometric properties of the specimens, to...

Briefs: Physical Sciences
Earth-Space Link Attenuation Estimation via Ground Radar Kdp

A method of predicting attenuation on microwave Earth/ spacecraft comm- unication links, over wide areas and under various atmospheric conditions, has been developed. In the area around the ground station locations, a nearly horizontally aimed polarimetric S-band ground radar measures...

Briefs: Physical Sciences
Update on Area Production in Mixing of Supercritical Fluids

The paper “Turbulence and Area Production in Binary-Species, Super- critical Transitional Mixing Layers” presents a more recent account of the research sum- marized at an earlier stage in “Area Production in Super- critical, Transitional Mixing Layers” (NPO-30425), NASA Tech...

Briefs: Physical Sciences
Dyakonov-Perel Effect on Spin Dephasing in n-Type GaAs

A paper presents a study of the contribution of the Dyakonov-Perel (DP) effect to spin dephasing in electron-donor-doped bulk GaAs in the presence of an applied steady, moderate magnetic field perpendicular to the growth axis of the GaAs crystal. (The DP effect is an electron-wave-...

Briefs: Photonics/Optics

Optical assemblies are used in an extensive range of technical applications to deliver a laser beam of a certain size, quality, and intensity to a region of space. While different...

Briefs: Photonics/Optics

Piezoelectric diffraction-based optoelectronic devices have been invented to satisfy requirements for switching signals quickly among alternative optical paths in optical communication...

Briefs: Photonics/Optics

A design concept has been proposed for an optomechanical apparatus that would implement a variable optical delay line with a fixed angle between its input and output light beams. The apparatus...

Briefs: Photonics/Optics

Mode-locked lasers of a proposed type would incorporate features of the design and operation of previously demonstrated miniature electro-optical modulators and erbium-doped glass lasers that contain...

Briefs: Photonics/Optics

A method of observing the interdiffusion of a pair of miscible liquids is based on the use of a common-path interferometer (CPI) to measure the spatially varying gradient of the...

Briefs: Photonics/Optics

A proposed method of implementing cross connections in an optical communication network is based on the use of a spatial light modulator (SLM) to form controlled diffraction patterns that...

Articles: Photonics/Optics

The advantages of cladding pumping fiber lasers were identified early in the research era of fiber laser technology. Essentially, fiber lasers allow efficient brightness conversion from the broad area pump laser diode into a...

Briefs: Mechanical & Fluid Systems

A compact, pneu- matically actuated filter shuttle has been invented to enable alternating imaging of a wind-tunnel model in two different spectral bands characteristic of the pressure and...

Briefs: Software
Software for Planning Scientific Activities on Mars

Mixed-Initiative Activity Plan Generator (MAPGEN) is a ground-based computer program for planning and scheduling the scientific activities of instrumented exploratory robotic vehicles, within the limitations of available resources onboard the vehicle. MAPGEN is a combination of two prior...

Briefs: Software
Software for Training in Pre-College Mathematics

The Intelligent Math Tutor (IMT) is a computer program for training students in pre-college and college-level mathe- matics courses, including fundamentals, intermediate algebra, college algebra, and trigonometry. The IMT can be executed on a server computer for access by students via the...

Briefs: Software
Software for Simulating a Complex Robot

RoboSim (Robot Simulation) is a computer program that simulates the poses and motions of the Robonaut — a developmental anthropomorphic robot that has a complex system of joints with 43 degrees of freedom and multiple modes of operation and control. RoboSim performs a full kinematic simulation of all...

Briefs: Software
Software Helps Retrieve Information Relevant to the User

The Adaptive Indexing and Retrieval Agent (ARNIE) is a code library, designed to be used by an application program, that assists human users in retrieving desired information in a hypertext setting. Using ARNIE, the program implements a comp- utational model for interactively learning what...

Briefs: Electronics & Computers

The new high-speed interconnect standards will dramatically change the way computer and communication systems are designed. Switch- based systems will be the winners in new high-performance designs,...

Briefs: Software
Software for Diagnosis of Multiple Coordinated Spacecraft

Distributed Real-Time Model-Based Diagnosis (DRMD) is a computer program for diagnosing faults in multiple spacecraft cooperating in a specific task (e.g., flying in formation to constitute an inter- ferometer). DRMD takes advantage of both (1) the superiority of model-based software for...

Briefs: Software
Software for Refining or Coarsening Computational Grids

A computer program performs calculations for refinement or coarsening of computational grids of the type called “structured” (signifying that they are geo- metrically regular and/or are specified by relatively simple algebraic expressions).

This program is designed to facilitate...

Briefs: Electronics & Computers

A computer-based simulation system creates a visual and haptic virtual environment for training a medical practitioner in laparoscopic surgery. Heretofore, it has been common practice to...

Briefs: Software
Software For Displaying Data From Planetary Rovers

Science Activity Planner (SAP) DownlinkBrowser is a computer program that assists in the visualization of processed telemetric data [principally images, image cubes (that is, multispectral images), and spectra] that have been transmitted to Earth from exploratory robotic vehicles (rovers) on...

Briefs: Electronics & Computers

The designs of microscopic toroidalcore inductors in integrated circuits of DC-to-DC voltage converters would be modified, according to a proposal, by filling the gaps in the cores...

Briefs: Electronics & Computers

Improved autoassociative neural networks, denoted nexi, have been proposed for use in controlling autonomous robots, including mobile exploratory robots of the biomorphic type. In comparison with...

Briefs: Electronics & Computers

A unique safety flasher powered by photovoltaic cells and ultracapacitors has been developed. Safety flashers are used wherever there are needs to mark actually or potentially...

Briefs: Mechanical & Fluid Systems
Continuous Tuning and Calibration of Vibratory Gyroscopes

A method of control and operation of an inertial reference unit (IRU) based on vibratory gyroscopes provides for continuously repeated cycles of tuning and calibration. The method is intended especially for application to an IRU containing vibratory gyroscopes that are integral parts of...

Briefs: Mechanical & Fluid Systems

The Morrison rotor, named after its inventor, is a hybrid rotor for use in a bearingless switched-reluctance electric motor. The motor is characterized as bearingless in the sense that it does...

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