Topic

A report discusses wind-tunnel tests of a scale model of a con- ceptual two-engine jet airplane designed to carry 10 passengers, have a range of 4,000 miles (≈6,400 km), cruise at a mach number of 2.0, and generate a low sonic boom [char- acterized by a shock overpressure of ≤ 0.5...

This report examines the simulation of eye move- ment and resulting stresses with mech- anical event simulation software to research retinal detachments, a condition that affects 25,000 people annually. The set-up of the bio- mechanical finite element model of the eye, as...

A report presents a study oriented toward optimization of synthetic jet actuators. [A syn- thetic jet actuator is a fluidic control device that partly resembles a loudspeaker. It typically comprises a piezo- electric actuator/ diaphragm situated in a cavity, facing an orifice or nozzle at the opposite end of...

A developmental instrumentation system rapidly acquires full Raman spectra of gas molecules. The system is based on the principle of multiplex coherent antistokes Raman spectroscopy (CARS) and incorporates improvements over prior multiplex CARS systems. Among the potential applications for systems...

Profile refractometry is a laser-based technique for measuring the index of refraction of a fluid as a function of time and position in a fluid. The technique was developed for use in quantifying the Soret effect in a binary fluid subject to an applied thermal gradient. (The Soret effect is the...

A technique for Fourier synthesis of optical pulses involves radio-frequency (RF) phase modulation of laser beams, Brillouin selective amplification of modulation sidebands, and, finally, generation of pulses through coherent superposition of (and thus interference among) the sidebands....

The Advanced Payload Transfer Measurement System (APTMS) comprises electromechanical sensors and sensor output-processing circuits. Designed specifically for measuring offsets between spacecraft payload trunnions and trunnion supports during ground-based payload-transfer operations, the APTMS could be...

Some improvements have been made to enhance the role of water as a test solvent for determining the amount of hydrocarbon nonvolatile residue (NVR) present on an item of hardware that is required to be totally or nearly devoid of such residue. Water is now used as an NVR-testing solvent...

Heat is the primary enemy of any electronic component. In order for an electronic device to have a long, problem-free life, cooling must be an important design consideration. The problem of cooling CPUs, in particular, has grown as processors have become more powerful. Water cooling systems...

This report examines design considerations in one of the most promising new areas of engineering – Micro Electro Mechanical Systems (MEMS). Designing and optimizing MEMS devices involves unique challenges, including analyzing the inter- dependent physical phenomena to which MEMS devices are sensitive and working...

A report presents additional information on the devices described in “Noise-Reducing Slots in Quantum-Well Infrared Photodetectors” (NPO-20518), NASA Tech Briefs, Vol. 25, No. 6 (June 2001), page 6a. To recapitulate: it was proposed that incorporation of suitably dimensioned crossed...

A report presents additional details about a class of massively parallel algorithms for finite-difference numerical solution of time-dependent partial differential equations (PDEs). Some aspects of these algorithms were described in two previous articles in NASA Tech Briefs; namely, “Massively Parallel...

Five-Axis, Three-Magnetic-Bearing Control Code (FATMaCC) is a C++-language computer program for controlling a magnetic thrust bearing in one degree of freedom and two magnetic radial bearings, each in two degrees of freedom. These bearings levitate a vertical-axis rotor for experiments on...

An artificial-intelligence computer program generates and evaluates plans for spacecraft missions subject to constraints associated with spacecraft designs. The input to the program includes spacecraft design parameters (e.g., slew rates and battery capacities) and mission parameters (e.g.,...

Generalized Timelines API is a computer program that provides (1) a means of representing arbitrary realworld state and resource information for use in planning, scheduling, and plan- and schedule-executing software and (2) an application-programming interface (API) that accelerates the...

A process for the fabrication of coated sapphire multimode optical fibers has been developed. Sapphire multimode optical fibers are suitable for use as embedded sensors for measuring mechanical and thermal stresses and strains in material specimens at temperatures up to about 1,500 °C.