May 2004

Briefs : Medical
FEA Software Enables Study of Tissue Ablation Dynamics

Regulatory agencies such as the US FDA must examine new medical devices to ensure that they are safe and effective. Sometimes, devices work successfully despite the fact that the mechanism of how they work isn't fully understood. In these cases, the FDA performs basic research to fill in...

Briefs : Electronics & Computers
Scalable Architecture for Multihop Wireless ad Hoc Networks

A scalable architecture for wireless digital data and voice communications via ad hoc networks has been proposed. Although the details of the architecture and of its implementation in hardware and software have yet to be developed, the broad outlines of the architecture are fairly...

Briefs : Electronics & Computers
Improved Thermoplastic/Iron-Particle Transformer Cores

A method of fabricating improved transformer cores from composites of thermoplastic matrices and iron-particles has been invented. Relative to commercially available laminated-iron-alloy transformer cores, the cores fabricated by this method weigh less and are less expensive. Relative to...

Briefs : Electronics & Computers
Cooperative Lander-Surface/Aerial Microflyer Missions for Mars Exploration

Concepts are being investigated for exploratory missions to Mars based on "Bioinspired Engineering of Exploration Systems" (BEES), which is a guiding principle of this effort to develop biomorphic explorers. The novelty lies in the use of a robust telecom architecture for...

Briefs : Electronics & Computers
Reduction of Phase Ambiguity in an Offset-QPSK Receiver

Proposed modifications of an offset quadri-phase-shift keying (offset- QPSK) transmitter and receiver would reduce the amount of signal processing that must be done in the receiver to resolve the QPSK fourfold phase ambiguity. Resolution of the phase ambiguity is necessary in order to...

Briefs : Electronics & Computers
Eight-Channel Continuous Timer

A custom laboratory electronic timer circuit measures the durations of successive cycles of nominally highly stable input clock signals in as many as eight channels, for the purpose of statistically quantifying the small instabilities of these signals. The measurement data generated by this timer are sent to a...

Briefs : Electronics & Computers
Radar for Monitoring Hurricanes From Geostationary Orbit

A document describes a scanning Doppler radar system to be placed in a geostationary orbit for monitoring the three-dimensional structures of hurricanes, cyclones, and severe storms in general. The system would operate at a frequency of 35 GHz. It would include a large deployable spherical...

Briefs : Physical Sciences
Time-Transfer System for Two Orbiting Spacecraft

A report describes the time-transfer system of the Gravity Recovery and Climate Experiment (GRACE), in which information on the distribution of Earth mass is extracted from position and time measurements for two spacecraft about 200 km apart in a circular, nearly polar orbit. Each spacecraft...

Briefs : Physical Sciences
Calculating Mass Diffusion in High-Pressure Binary Fluids

A comprehensive mathematical model of mass diffusion has been developed for binary fluids at high pressures, including critical and supercritical pressures. Heretofore, diverse expressions, valid for limited parameter ranges, have been used to correlate high-pressure binary mass-...

Briefs : Physical Sciences
Current Pulses Momentarily Enhance Thermoelectric Cooling

The rates of cooling afforded by thermoelectric (Peltier) devices can be increased for short times by applying pulses of electric current greater than the currents that yield maximum steady-state cooling. It has been proposed to utilize such momentary enhancements of cooling in...

Briefs : Physical Sciences
Improved Cryostat for Cooling a Wide Panel

An improved cryostat has been developed for cooling a wide panel evenly over its surface to a temperature of -423 °F (≈-253 °C) by use of liquid helium. Originally, the cryostat was to be used in measuring apparent strains in wide aluminum/ lithium panels as functions of temperature in order to...

Briefs : Software
Making the Monte Carlo Approach Easier and Faster

Originally introduced by Nicholas Metropolis during the Manhattan Project, Monte Carlo methods today have very broad and extensive use in various areas of science and technology. Random number generators (RNGs) are a core part of any Monte Carlo method, having a significant impact on the overall...

Briefs : Information Technology
Higher-Order Finite Elements for Computing Thermal Radiation

Two variants of the finite-element method have been developed for use in computational simulations of radiative transfers of heat among diffuse gray surfaces. Both variants involve the use of higher-order finite elements, across which temperatures and radiative quantities are assumed...

Briefs : Information Technology
Automation of Design Engineering Processes

A method, and a computer program that helps to implement the method, have been developed to automate and systematize the retention and retrieval of all the written records generated during the process of designing a complex engineering system. It cannot be emphasized strongly enough that “all the...

Briefs : Materials
Curing Composite Materials Using Lower-Energy Electron Beams

In an improved method of fabricating composite-material structures by laying up prepreg tapes (tapes of fiber reinforcement impregnated by uncured matrix materials) and then curing them, one cures the layups by use of beams of electrons having kinetic energies in the range of 200 to...

Briefs : Materials
Aluminum-Alloy-Matrix/Alumina-Reinforcement Composites

Isotropic composites of aluminum alloy matrices reinforced with particulate alumina have been developed as lightweight, high-specific-strength, less expensive alternatives to nickel-base and ferrous superalloys. These composites feature a specific gravity of about 3.45 g/cm3 and specific...

Briefs : Materials
Fibrous-Ceramic/Aerogel Composite Insulating Tiles

Fibrous-ceramic/aerogel composite tiles have been invented to afford combinations of thermal-insulation and mechanical properties superior to those attainable by making tiles of fibrous ceramics alone or aerogels alone. These lightweight tiles can be tailored to a variety of applications that...

Briefs : Materials
Urethane/Silicone Adhesives for Bonding Flexing Metal Parts

Adhesives that are blends of commercially available urethane and silicone adhesives have been found to be useful for bonding metal parts that flex somewhat during use. These urethane/silicone adhesives are formulated for the specific metal parts to be bonded. The bonds formed by these...

Briefs : Software
Windows®-Based Software Models Cyclic Oxidation Behavior

Oxidation of high-temperature aerospace materials is a universal issue for combustion-path components in turbine or rocket engines. In addition to the question of the consumption of material due to growth of protective scale at use temperatures, there is also the question of cyclic...

Briefs : Software
Software for Analyzing Sequences of Flow-Related Images

Spotlight is a computer program for analysis of sequences of images generated in combustion and fluid physics experiments. Spotlight can perform analysis of a single image in an interactive mode or a sequence of images in an automated fashion. The primary type of analysis is tracking of...

Briefs : Information Technology
Increasing Accuracy in Computed Inviscid Boundary Conditions

A technique has been devised to increase the accuracy of computational simulations of flows of inviscid fluids by increasing the accuracy with which surface boundary conditions are represented. This technique is expected to be especially beneficial for computational aeroacoustics,...

Briefs : Mechanical & Fluid Systems
Polyethylene Natural-Gas Valves Designed With Finite-Element Analysis

In response to a growing industry trend toward corrosion- and maintenance-free natural-gas valves, Kerotest designed POLYBALL™™ 1/2" to 12" standard- and full-port valves made of medium- and high-density polyethylene. The valves also had to meet or exceed ASME B16.40, ASTM...

Briefs : Manufacturing & Prototyping
Low-Temperature Plasma Functionalization of Carbon Nanotubes

A low-temperature plasma process has been devised for attaching specified molecular groups to carbon nanotubes in order to impart desired chemical and/or physical properties to the...

Briefs : Photonics/Optics
Lightweight, Flexible, Thin, Integrated Solar-Power Packs

Lightweight, flexible, thin, one-piece, solar-power packs are undergoing development. Each power pack of this type is a complete, modular, integrated power-supply system comprising three power subsystems that, in conventional practice, have been constructed as separate units and connected...

Briefs : Photonics/Optics
Fresnel Lenses for Wide- Aperture Optical Receivers

Wide-aperture receivers for free-space optical communication systems would utilize Fresnel lenses instead of conventional telescope lenses, according to a proposal. Fresnel lenses weigh and...

Briefs : Materials
Embedded Heaters for Joining or Separating Plastic Parts

A proposed thermal-bonding technique would make it possible to join or separate thermoplastic parts quickly and efficiently. The technique would eliminate the need for conventional...

Briefs : Photonics/Optics
Laser Sensor-Based System for Automated Inspection of Jet Engine Blades

A system has been developed to replace manual measurement of small jet engine blades during safety and performance inspections. The high-speed, automated system consists...

Briefs : Manufacturing & Prototyping
Ordered Nanostructures Made Using Chaperonin Polypeptides

A recently invented method of fabricating periodic or otherwise ordered nanostructures involves the use of chaperonin polypeptides. The method is intended to serve as a potentially...

Briefs : Photonics/Optics
Hand-Held Color Meters Based on Interference Filters

Small, inexpensive, hand-held optoelectronic color-measuring devices based on metal-film/dielectric-film interference filters are undergoing development. These color meters could be...

Briefs : Mechanical & Fluid Systems
Two-Stage Solenoid

A proposed design for a solenoid-based electromechanical actuator would provide greater starting force than does a comparable conventional design. As used here, "starting force" signifies the magnetic force exerted by the actuator at one end of its stroke when the gap in its magnetic circuit is the widest. A solenoid of...

Briefs : Electronics & Computers
Ambient-Light-Canceling Camera Using Subtraction of Frames

The ambient-light-canceling camera (ALCC) is a proposed near-infrared electronic camera that would utilize a combination of (1) synchronized illumination during alternate frame periods and (2) subtraction of readouts from consecutive frames to obtain images without a background component...

Briefs : Photonics/Optics
Dual-Frequency Airborne Scanning Rain Radar Antenna System

A compact, dual-frequency, dual-polarization, wide-angle-scanning antenna system has been developed as part of an airborne instrument for measuring rainfall. This system is an...

Briefs : Mechanical & Fluid Systems
Improved Ball-and-Socket Docking Mechanism

A proposed docking mechanism would form a ball-and-socket joint in the docked condition. The mechanism could tolerate significant initial misalignment because it would include an alignment cone that...

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