June 2005

Briefs: Information Technology
Fuzzy/Neural Software Estimates Costs of Rocket-Engine Tests

The Highly Accurate Cost Estimating Model (HACEM) is a software system for estimating the costs of testing rocket engines and components at Stennis Space Center.

Briefs: Information Technology
Real-Time Principal-Component Analysis

A recently written computer program implements dominant-element-based gradient descent and dynamic initial learning rate (DOGEDYN), which was described in "Method of Real-Time Principal-Component Analysis" (NPO-40034) NASA Tech Briefs, Vol. 29, No. 1 (January 2005), page 59.

Briefs: Information Technology
NASA Records Database

The NASA Records Database, comprising a Web-based application program and a database, is used to administer an archive of paper records at Stennis Space Center. The system begins with an electronic form, into which a user enters information about records that the user is sending to the archive.

Briefs: Information Technology
Decision Support for Emergency Operations Centers

The Flood Disaster Mitigation Decision Support System (DSS) is a computerized information system that allows regional emergency-operations government officials to make decisions regarding the dispatch of resources in response to flooding.

In the race to deliver drugs to market more quickly, biopharmaceutical companies need to classify and interpret data at unprecedented rates with tools that eliminate...

Briefs: Medical
Microwave Treatment of Prostate Cancer and Hyperplasia

Microwave ablation in the form of microwave energy applied to a heart muscle by a coaxial catheter inserted in a vein in the groin area can be used to heat and kill diseased heart cells. A microwave catheter has been developed to provide deep myocardial ablation to treat ventricular...

Briefs: Materials
Modifications of a Composite-Material Combustion Chamber

Two short reports discuss modifications of a small, lightweight combustion chamber that comprises a carbon/carbon composite outer shell and an iridium/rhenium inner liner. The first report discusses chamber design modifications made as results of hot-fire tests and post-test...

Briefs: Materials
Development of Carbon-Nanotube/Polymer Composites

A report presents a short discussion of one company's effort to develop composites of carbon nanotubes in epoxy and other polymer matrices.

Briefs: Materials
Multicomponent, Rare-Earth-Doped Thermal-Barrier Coatings

Multicomponent, rare-earth-doped, perovskite-type thermal-barrier coating materials have been developed in an effort to obtain lower thermal conductivity, greater phase stability, and greater high-temperature capability, relative to those of the prior thermal-barrier coating material of...

Phenylethynyl containing reactive additive (PERA) compounds and mixtures have been found to be useful for improving the processability of oligomers, polymers, cooligomers, and copolymers...

Briefs: Test & Measurement
Wheel Electrometer System

The electrodes of this electrometer are embedded in a wheel of an exploratory robotic vehicle, utilizing the wheel motion to bring the electrodes into proximity or contact with the soil. Each electrode resides in one of two types of sensor modules: electric-field (ELF) or triboelectric (TRIBO). In either type, what is...

Briefs: Test & Measurement
Cryogenic High-Sensitivity Magnetometer

A proposed magnetometer for use in a cryogenic environment would be sensitive enough to measure a magnetic-flux density as small as a picogauss (10-16 Tesla). In contrast, a typical conventional flux-gate magnetometer cannot measure a magnetic-flux density smaller that about 1 microgauss (10-10 Tesla).

Aircraft and other vehicles are often kept in service beyond their original design lives. As they age, they become susceptible to system malfunctions and fatigue. Unlike future...

A technique has been devised for measuring the relative humidity levels in the protective helium/water vapor atmosphere in which the Declaration of Independence, the United States Constitution,...

The figure shows a prototype of a relatively inexpensive electronic monitoring apparatus that measures and records selected parameters of lightning induced transient voltages on...

Briefs: Physical Sciences
Thermal Imaging of Earth for Accurate Pointing of Deep-Space Antennas

A report discusses a proposal to use thermal (long-wavelength infrared) images of the Earth, as seen from spacecraft at interplanetary distances, for pointing antennas and telescopes toward the Earth for Ka-band and optical communications.

Briefs: Physical Sciences
Shock Waves in a Bose-Einstein Condensate

A paper presents a theoretical study of shock waves in a trapped Bose-Einstein condensate (BEC).

Devices called “solid-state ferroelectric-based sources” (SSFBSs) are under development as sources of electrons, ions, ultraviolet light, and x-rays for diverse applications in...

Briefs: Physical Sciences
Dusty-Plasma Particle Accelerator

A dusty-plasma apparatus is being investigated as means of accelerating nanometer- and micrometer-sized particles. Applications for the dusty-plasma particle accelerators fall into two classes:

Briefs: Physical Sciences
Code for Analyzing and Designing Spacecraft Power System Radiators

A specific application is for Stirlingcycle/linear-alternator electric-power systems coupled to radioisotope general-purpose heat sources. GPHRAD affords capabilities and options to account for thermophysical properties (thermal conductivity, density) of either metal-alloy or...

An improved miniature time-of-flight mass spectrometer has been developed in a continuing effort to minimize the sizes, weights, power demands, and costs of mass spectrometers for such...

An alternative method of controlled shifting of the center of mass has been proposed as a means of locomotion of a robot that comprises mostly a payload inside a hollow,...

Briefs: Semiconductors & ICs
Improved Method of Manufacturing SiC Devices

The phrase, "common-layered architecture for semiconductor silicon carbide" ("CLASSiC") denotes a method of batch fabrication of microelectromechanical and semiconductor devices from bulk silicon carbide. CLASSiC is the latest in a series of related methods developed in recent years in continuing...

Briefs: Semiconductors & ICs
LC Circuits for Diagnosing Embedded Piezoelectric Devices

A recently invented method of nonintrusively detecting faults in piezoelectric devices involves measurement of the resonance frequencies of inductor-capacitor (LC) resonant circuits. The method is intended especially to enable diagnosis of piezoelectric sensors, actuators, and...

Briefs: Software
Spacecraft Antenna Clusters for High EIRP

Several documents in a collection discuss a proposal to use clusters of appropriately phased, relatively small microwave antennas to obtain high levels of effective isotropically radiated power (EIRP) for transmission of data from spacecraft to Earth during exploration of distant planets. The advantages...

Briefs: Software
Decision Support for Emergency Operations Centers

The Flood Disaster Mitigation Decision Support System (DSS) is a computerized information system that allows regional emergency-operations government officials to make decisions regarding the dispatch of resources in response to flooding. The DSS implements a real-time model of inundation...

Briefs: Electronics & Computers
Modeling and Diagnostic Software for Liquefying-Fuel Rockets

A report presents a study of five modeling and diagnostic computer programs considered for use in an integrated vehicle health management (IVHM) system during testing of liquefying-fuel hybrid rocket engines in the Hybrid Combustion Facility (HCF) at NASA Ames Research Center.

Briefs: Electronics & Computers
Progress on a Multichannel, Dual-Mixer Stability Analyzer

Several documents describe aspects of the continuing development of a multichannel, dual-mixer system for simultaneous characterization of the instabilities of multiple precise, low noise oscillators.

Briefs: Electronics & Computers
Nanowire Thermoelectric Devices

Nanowire thermoelectric devices, now under development, are intended to take miniaturization a step beyond the prior state of the art to exploit the potential advantages afforded by shrinking some device...

Briefs: Mechanical & Fluid Systems
Fasteners for Printed Circuit Board Attachment

No matter how sophisticated or advanced, electronic components must be attached reliably and securely if they are to deliver optimum performance. Beyond this universal requirement, particular...

Briefs: Electronics & Computers
Patch Antenna Fed via Unequal-Crossed-Arm Aperture

A proposed rectangular-patch antenna for transmitting or receiving microwave circularly polarized (CP) radiation would be fed via a cross-shaped aperture that would have unequal arms and would, in turn, be fed at a single point via a microstrip transmission line. As a consequence of the...

Briefs: Manufacturing & Prototyping
Parylene C as a Sacrificial Material for Microfabrication

Although Parylene C cannot be patterned lithographically like photoresists, it nevertheless extends the range of processing options by offering a set of properties that are suitable for microfabrication and are complementary to those of photoresists. The compatibility of Parylene C with...

Briefs: Manufacturing & Prototyping
In Situ Electrochemical Deposition of Microscopic Wires

A method of fabrication of wires having micron and submicron dimensions is built around electrochemical deposition of the wires in their final positions between electrodes in integrated...

Thin, transparent layers comprising mats of carbon nanotubes have been proposed for providing lateral (that is, inplane) electrical conductivities for collecting electric currents...