Magazine

Several computer programs, denoted collectively as the "CFD Seal Analysis Industrial Codes," have been developed to enable rapid parametric analyses and optimization of designs of a variety of turbomachinery seals. These programs could be used to design the seals that will be needed in future...

Inventors at the Cornell Research Foundation have devised a method of selective metallization of high-temperature semiconductors to produce ohmic or rectifying contacts. The process consists of three phases: a lithographic step to define the areas of contact, preparation of the...

This program is designed as a real-time aid to analyze system health. The Propulsion Advisory Tool (PAT) is a knowledge-based computer program that monitors real-time data from more than 300 sensors in the space shuttle Main Propulsion System (MPS). The thermal conditions within...

A computer program estimates great-circle-arc (GARC) flightpaths of multiple aircraft, given time-tagged point locations from radar sightings of the aircraft. The problem of generating such estimates is called a "clustering" problem, and is solved in this instance by use of a neural-network...

An improved method of noncontact measurement of the surface tension of a molten material has been developed, partly to overcome the disadvantages of contact measurement techniques as described in the preceding article, "Noncontact Measurement of Resistivity of Molten Material"...

A report describes experiments on the concept described in "Real-Time Collision Avoidance for a Robot Arm" (NPO-19861), NASA Tech Briefs, Vol. 20, No. 12 (December 1996), page 98. Under this concept, collision-avoidance software processes data computed by model-based obstacle-detection software...

Micromachined planar arrays of detectors that could operate either as photodiodes or as bolometers have been proposed for use in detecting photons in applications in which broad spectral responses are required. The availability of either of the two modes would enable operation throughout the spectrum, from...

It is now possible to determine the electrical resistivity of a molten sample of a pure, electrically conductive material (a metal or semiconductor), without contact between the sample or any solid object. Once the electrical resistivity has been determined, the thermal conductivity can be...