Briefs: Electronics & Computers

Interlayer Stripline Transition

A proposed multilayer metal-film/dielectric-plate laminate would serve as a passive radio-frequency (RF) interlayer stripline transition. This device is designed to provide RF coupling from (a) an input...

Briefs: Materials

Another Improved Method for Making Fuel-Cell Electrodes

An improved method of fabricating membrane electrode structures for methanol fuel cells is similar to the method described in the preceding article, except that in this method, the...

Briefs: Physical Sciences

Thermal and Mechanical Effects in Graded Composite Cylinders

"HOTCFGM-1D" denotes a collection of four computer programs, plus the underlying theory, for calculating thermomechanical and inertial effects in axisymmetric cylindrical...

Briefs: Electronics & Computers

Vertical-Bloch-Line Memories Containing Stacked Chips

Vertical-Bloch-line (VBL) memory devices of a proposed type would include stacks of VBL memory chips plus other components (see figure on next page). Each chip would be square,...

Briefs: Information Technology

Neural-Network Modeling of Flow Properties of an Object

A method of computational simulation of the aerodynamic- or hydrodynamic-flow performance features of objects involves the use of neural-network mathematical models implemented in...

Briefs: Materials

Electric-Arc and Electrochemical Texturing of Surfaces

Electric arcs and electrochemical etching can be used to impart microscopic textures to surfaces of metals. In electric-arc texturing, one strikes an arc between a water-cooled...

Briefs: Robotics, Automation & Control

Miniature Lambda Sensors for Engine-Control Systems

Small, lightweight sensors that exploit the unique characteristics of nanoceramics are being developed for use in measuring air/fuel ratios in the exhaust gas flows of advanced aircraft...

Briefs: Electronics & Computers

Broad-Band GaAs/AlₓGa₁₋ₓAs QWIPs

GaAs/Al_xGa_1-xAs quantum-well infrared photodetectors (QWIPs) with broad-band responses are undergoing development. The broad-band responses are obtained by varying the depths and...

Briefs: Physical Sciences

Sensor for Monitoring Concentration of Methanol in Water

A robust sensor based on the electrochemical oxidation of methanol has been developed for use in measuring the concentration of methanol dissolved in water. The sensor is expected to...

Briefs: Electronics & Computers

InₓGa₁₋ₓP/InₓGa₁₋ₓAs-on-Ge Solar Photovoltaic Cells

Monolithic, tandem two-junction In_xGa_1-xP/In_xGa_1-x As-on-Ge Solar Photovoltaic Cells are being developed. The cells are designed...

Briefs: Robotics, Automation & Control

Thermal Batteries Made With Nanostructured Material

Early experiments in a continuing research program have demonstrated that thermal batteries made from powdered solid electrode and electrolyte materials can be improved by use of smaller...

Briefs: Information Technology

Algorithm Accelerates Solution of Digraph Reliability Models

The SourceDoubls algorithm efficiently solves for singletons and doubletons of a digraph reliability model (defined below). In the case of a complex system of hardware and/or...

Briefs: Electronics & Computers

Lead Bromide Crystals Doped With Silver Bromide

Doping with silver bromide has been found to be an effective technique for enhancing the optical homogeneity and other qualities of single crystals of lead bromide. These crystals are grown...

Briefs: Robotics, Automation & Control

Solar Heating of Batteries in Cold Environments

According to a proposal for small electric-power systems that must operate in cold environments, heat released in the operation of solar photovoltaic arrays with solar concentrators would be...

Briefs: Physical Sciences

Programmable Multizone Directional-Solidification Furnaces

Programmable multizone furnaces with enhanced designs have been proposed for use in processing materials by directional solidification or, optionally, by related techniques of...

Briefs: Information Technology

Diagnosing Rotating Machinery Using Spectral Distribution Functions

A method for detecting and characterizing faults in a rotating machine involves analysis of selected aspects of the evolution of the spectral distribution function (SDF) of...

Briefs: Manufacturing & Prototyping

Software for Minimizing and Removing Burrs in Manufacturing

An integrated suite of computer programs is undergoing development to address issues pertaining to the formation of burrs — undesired projections of metal that are generated on...

Briefs: Robotics, Automation & Control

Liquid-Circulation System Keeps Aircrew Members Cool

Each member of the aircrew of an advanced fighter airplane wears a complex, multilayered ensemble that imposes a significant thermal burden by inhibiting normal transport of heat from the...

Briefs: Electronics & Computers

Improved Electrical Connections for Thin-Film Thermocouples

Improved electrical connections have been developed for thin-film thermocouples used to measure temperatures on the surfaces of ceramic-matrix composite-material specimens during...

Briefs: Materials

Improved Fabrication of Electrodes for Methanol Fuel Cells

A method of fabricating membrane electrode structures for methanol fuel cells involves, among other things, the use of improved sprayers to deposit inks containing catalytic metals...

Briefs: Physical Sciences

Scanning Surface-Plasmon Filters for Miniature Spectrometers

Scanning filters based on surface plasmons would be used as the adjustable wavelength-selective (band-pass) devices in a class of proposed miniature spectrometers. These filters...

Briefs: Mechanical & Fluid Systems

High-Altitude Flight Test of the Perseus B Airplane

The Perseus B remotely piloted vehicle (RPV) has achieved a record altitude for a single-engine, propeller-driven airplane of 60,260 ft (18,367 m) on June 27, 1998. The Perseus B is one of...

Briefs: Robotics, Automation & Control

Human-Powered Centrifuges and Stationary Exercise Stations

Human-powered machines that can be operated as centrifuges or as stationary exercise stations have been invented. These machines are suitable for a variety of terrestrial and...