An unconventional and highly effective technique has been devised to reduce cyclic errors that arise in the operation of a displacement-measuring heterodyne optical interferometer. The cyclic errors are attributable largely to undesired small exchanges of power between light beams that...

A compact instrument includes a fiber-optic probe that utilizes the evanescent-wave interaction to measure the accumulation of a biofilm. This instrument is a prototype of instruments that could be used to effect continuous monitoring and provide early warning of biofilms associated with...

Some changes have been made in the fabrication of PSSA/ PVDF-based membrane/electrode assemblies for direct methanol fuel cells. The effect of the changes is to improve the electrochemical performances of the cells.

Better Elicitation and Communication of Arguments Underlying Software Engineering (BECAUSE) is a computer program that records and codifies the rationale that underlies decisions made in the course of developing software. To minimize the additional sensory, cognitive, and motor demands upon the...

Multi-Rover Integrated Science Understanding System (MISUS) is a computer program designed to coordinate the activities of multiple small, instrumented robotic vehicles (rovers) engaged in autonomous scientific exploration of the surface of Mars. MISUS includes a component that utilizes...

Virtual Procurement Office (VPO) is a Web-based application program designed for use by procurement professionals throughout NASA. Prior to the development of VPO, each of the 700+ NASA procurement pro- fessionals had to spend much time searching numerous locations on-line and off-line...

Health and Environ- mental Resource System (HERS) is a relational-database computer program with a graphical user interface that assists members of an envi- ronmental health organization in the collection, analysis,

and reporting of data pertaining to industrial hygiene, radiation...

Cisco IOS Manager (CIOSMAN) is a computer program that generates a graphical user interface for managing configuration files for an Internet-Protocol router. [In this context, “IOS” signifies the Cisco Internet- working Operating System and “router” signifies a system of...

An improved method of generating audible alarms has been invented for stressful environments in which there may be consid- erable background noise and where the intended recipients of the alarms also need to pay att- ention to sounds other than the alarms. An aircraft cockpit is a...

Connector test clamps (CTCs) are clamping electrical connectors designed for use in testing electrical continuity from the backshell of a connector at one end of a shielded electrical cable, through the cable shield, to the backshell at the other end of the cable. CTCs increase the...

During development and production, cell phones and other portable devices must be tested and calibrated with a power source that accurately simulates battery operation. To avoid erroneous calibration and false failure indications in devices under test (DUTs),...

The Perilog methods and software provide a suite of data-mining tools. Perilog retrieves and organizes data from any sequence of terms that are contextually associated (e.g., text, music, genetic sequences). Perilog data mining includes: (1) keyterm-in-context search; (2) flexible, model-based...

BEAM is a method of real-time, automated analysis and diagnosis applicable to a broad class of complex electromechanical systems, including spacecraft, aircraft, and process-control systems. Some aspects of its operation were described in “Reusable Software for Autonomous Diagnosis of Complex...

A generalized data processor, proposed for use in the reception of binaryphase-shift-keyed (BPSK) radio signals, provides preliminary estimates of the block and convolutionally encoded symbols that are meant to be con- veyed by the BPSK modulation. In a process denoted...

A prototype of a relatively inexpensive S-band transponder has been developed for use aboard a spacecraft as part of a NASA space- craft tracking and data network (STDN). The transponder design incorporates recent advances in digital processing of received radio signals. Notable features of...

A method of semi- automated ident- ification of biomaterials, now under development, is based on the use of a combination of neural-network and of self- organizing, molecular, and supervised-learning algorithms to analyze multispectral images. The method is...

Data is any company’s most valuable asset. Archiving systems are essential to ensuring that valuable data is preserved. A wide variety of technologies exists, but tape medium remains a popular choice for data backup due to its comparatively low cost and large capacity for data storage....

The fabrication of membrane/electrode assemblies (MEAs) for direct methanol fuel cells can be modified to make the cathodes hydro- phobic. These modifications improve the performances of the fuel cells, as explained below.

A class of developmental membrane electrolyte materials for methanol/air and hydrogen/air fuel cells is exemplified by a composite of (1) a melt-processable polymer [in particular, poly(vinylidene fluoride) (PVDF)] and (2) a solid proton conductor (in particular, cesium hydrogen...

Windows that absorb x rays and are transparent to visible light can be made by compression molding of tantalum oxide/polymer composite materials. The main x-ray-absorbing medium in these windows is tantalum instead of lead, which is the traditional main x-ray-absorbing medium. These composite windows have been...

Computational test cases have been selected from archived sets of data acquired some years ago in wind-tunnel experiments on a clipped delta wing equipped with a hydraulically actuated trailing-edge control surface. In some of the experiments, the wing was subjected to pitching...

Flight data gathered by use of the F-18 System Research Aircraft (SRA) based at Dryden Flight Research Center have been used to estimate stability and control derivatives for a baseline F-18 airplane. The data were obtained in the high-dynamic-pressure range of the F-18 flight envelope in an experiment...

Experiments have demonstrated the feasibility of generating fountains and fogs over a body of water (see Figure 1) by utilizing high-intensity ultrasound to induce acoustic streaming, cavitation, and atomization. The transducer used in the experiments had a 10-cm diameter and a 10-cm focal length, was...

An improved closed-loop, two-stage pulse-tube refrigerator provides 4 W of cooling power at a temperature of 15 K. The original intended application of this refrigerator is in preventing boiloff of liquid hydrogen from a propellant tank aboard a spacecraft. The basic refrigerator design can also be...

An easy-to-implement design concept shows promise for improving the performances of impact tool bits used in abrading surfaces, drilling, and coring of rock and rocklike materials. The concept is especially applicable to tools actuated with a combination of ultrasonic and sonic vibrations, as in the...

A report presents additional information about the Impairscope — an instrument for noninvasive meas- urement of fine neuromuscular control and, more particularly, for quantifying the degradation of neuromuscular performance under psychological stress. The instrument, previously called the...

Several groups of methods of enhanced bioproduction and extraction of taxanes have been invented. Taxanes (see figure) have exhibited potential as drugs for treatment of cancer and congenital polycystic kidney disease. One taxane — paclitaxel (more widely known under the trade name Taxol™) —...

A procedure has been devised for the use of steam to sterilize a water-purification cartridge, chrom- atographic column, or other closed packed column that is required to be kept filled with water and from which it is required to exclude air bubbles, which could impede flow. For the...

Materials and equipment for determining whether samples of potable water contain harmful microbes have been packaged in a kit. Designed for use aboard spacecraft, the kit is also suitable for terrestrial use in a laboratory or in the field. The kit holds the sample, nutrient, and waste liquids in a closed system.