Briefs: Photonics/Optics

Coherent gradient sensing (CGS) is a diffraction-based, noncontact optical technique for measuring the slight curvature of a nearly flat thin film or specimen surface. CGS is especially...

Briefs: Electronics & Computers
Self-Checking Circuitry for Detecting Single-Event Latchups

High-performance electronic circuits would incorporate self-checking features for detection of radiation-induced single-event latchups (SELs), according to a proposal. The basic SEL-detection scheme calls for redundant circuitry and a current-voting scheme similar to voting schemes...

Briefs: Materials

Experiments have shown that improved hydride-forming negative electrodes for rechargeable nickel/metal hydride (Ni/MH) electrochemical cells can be made by substituting Ge for...

Briefs: Photonics/Optics

Voltage-tunable optical band-pass filters based on surface plasmon waves have been proposed. These filters would function at both visible and infrared wavelengths. Whereas...

Briefs: Photonics/Optics

A process for the growth of single-crystal (epitaxial) multilayer films has been developed at the Naval Surface Warfare Center, Dahlgren Division. This process is predicated on the preparation of a...

Briefs: Physical Sciences
Miniature Microscope Without Lenses

In a proposed optical microscope, the focusing optics of a conventional microscope would be supplanted by a combination of a microchannel filter and an advanced electronic image sensor. Elimination of focusing optics would eliminate the need for the time-consuming focusing operation, making it possible to...

Briefs: Photonics/Optics

The methods described are used with existing fiber optic technologies, and are based on several patents and on disclosures now before the U.S. Patent and Trademark Office. The patents are No....

Briefs: Physical Sciences
Microlenses for Calibrating Phase Doppler Particle Analyzers

Simple optical devices called "scattering reticles" have been invented for calibrating Phase Doppler Particle Analyzers (PDPAs), which are optical instruments that analyze scattered light to determine the sizes and velocities of droplets. A scattering reticle comprises a polymeric...

Briefs: Physical Sciences

The proposed electron microscope would function without the need for external vacuum pumps and thus have a significant reduction in size, mass, and power consumption, as compared to...

Briefs: Mechanical & Fluid Systems

Devices are proposed that would sublime solid propellants to generate small thrusts for maneuvering spacecraft with masses of no more than 15 kg. With solids rather than gases in propellant tanks, there would...

Briefs: Materials

Experiments have shown that improved hydride-forming negative electrodes for rechargeable nickel/metal hydride (Ni/MH) electrochemical cells can be made by substituting Sn for...

Briefs: Mechanical & Fluid Systems

The figure illustrates a device that flexes to allow rotation about a single axis through a total range of ±12°. This device was designed to offer the following advantages over commercial flexural pivots:

Briefs: Robotics, Automation & Control

Jewellike bearings have been devised to enhance the performance and safety of small rotary pumps that are used to increase or sustain flows of blood in cardiac patients. A pump of this type includes a...

Briefs: Photonics/Optics

The Boeing Company has developed fiber-laser-amplifier technology representing the latest in diode-laser-pumped systems, providing high output power, high brightness, tunability,...

Briefs: Electronics & Computers

A single-block fixture enables the rapid and accurate electrical characterization of planar microwave electronic components, by use of the through-reflect-line (TRL) technique, in...

Briefs: Physical Sciences

Easy-to-use high-temperature strain-sensor systems based on strain gauges made from Pd/Cr-alloy wires have been developed. These systems include strain-gauge units comprising Pd/Cr wires...

Briefs: Materials

Current production thermal-barrier coatings (TBCs) have been shown to be capable of reducing the average temperatures of metallic components by 50 to 80 °C and hot-spot temperature by...

Briefs: Electronics & Computers

Experiments have revealed that stable breakdown-voltage characteristics can be achieved in silicon carbide rectifiers. Stable breakdown-voltage characteristics are essential to the...

Briefs: Photonics/Optics

Semimonolithic resonant structures external to lasers have been proposed for use in optical frequency-conversion applications - for example, doubling the frequencies of laser beams....

Briefs: Materials

A probabilistic method has been developed for use in designing a composite-material structure to achieve a balance between maximum reliability and minimum cost. This method accounts...

Briefs: Electronics & Computers
Single-Event Latchup Protection of Integrated Circuits

Many commercially available advanced-technology CMOS and bipolar integrated circuits are susceptible to single-event latchup (SEL) effects caused by heavy ions or protons from cosmic rays or solar flares, making them unsuitable for satellite applications. Remanufacturing the integrated...

Briefs: Electronics & Computers

The term "inverse rectenna" may seem like an oxymoron at first glance. However, preliminary experiments have demonstrated that a rectenna of suitable design can be made to operate in...

Briefs: Mechanical & Fluid Systems

Detailed measurements of complex flow fields within the NASA Low Speed Centrifugal Compressor (LSCC) have been acquired. The measurement data provide insight into the fundamental...

Briefs: Electronics & Computers

As electronic circuits become more densely packaged and higher in power, maintaining them within permissible temperature ranges becomes a major issue. This is especially true in the case of...

Briefs: Electronics & Computers
SQUID-Based Asymmetric Planar Gradiometer

Berkeley Laboratory researchers have demonstrated a novel superconducting gradiometer that helps to reduce ambient magnetic field noise generated by relatively distant sources in favor of tiny magnetic signals generated by a local source. This is another step toward the operation of SQUID-based...

Briefs: Mechanical & Fluid Systems

Automatic valves have been proposed for shutting off flows of liquids when abnormally large accelerations occur. These valves could be used, for example, to prevent outflows of...

Briefs: Robotics, Automation & Control

Lightweight, inflatable robotic vehicles (rovers) that superficially resemble beach balls and that could be driven by wind and/or electric power are undergoing development. These rovers were...

Briefs: Electronics & Computers

An electronic system that comprises airborne and ground-based subsystems generates data for a global real-time interactive map (GRIM) that displays the current position and...

Briefs: Mechanical & Fluid Systems

The Spacecraft Autonomous Navigation System using GPS for Earth Orbiters (SANS-GEO) computer program is designed to perform the navigation calculations that will enable the New...

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