Briefs : Electronics & Computers
Airborne Multichannel Swept-Tuned Spectrum Analyzer

Two airborne spectrum analyzers were developed for acquiring dynamic data, characterized by frequencies up to 25 kHz, from a hypersonic-crossflow-transition experiment aboard the air-launched Pegasus® space booster rocket (see Figure 1). Real-time transmission of time histories of...

Briefs : Electronics & Computers
Improved Eye-Tracking Apparatus

A previously developed apparatus that tracks the orientation of the human eye has been modified to make it less susceptible to error induced by ambient infrared light. The apparatus is a commercial product intended primarily for use as a computer-control interface for a person who is physically unable to use a...

Briefs : Test & Measurement
Algorithm for Calibrating an Imaging Interferometer

An algorithm has been devised to greatly simplify and improve the calibration and the reduction of systematic noise of an imaging interferometer or other similar interferometric instrument. Prior to the advent of this algorithm, such calibration was achieved by means of a conventional...

Briefs : Test & Measurement
Miniature Birefringence-Measuring System

A miniature birefringence-measuring system has been developed for use in investigating extensional flows of non-Newtonian polymers in microgravity. The system could also be used on Earth to perform general optical-retardation and dichroism measurements, to measure stresses with high sensitivity, to...

Briefs : Information Technology
Software Collects Planning and Scheduling Requirements

Interim User's Requirements Collection (IURC) is a software system that generates an interactive graphical user interface that enables users of the International Space Station (ISS) to specify their payload-planning and -scheduling requirements via the World Wide Web (WWW). IURC...

Briefs : Information Technology
Software for Ground Processing of Data From Landsat 7

Three computer programs have been developed for ground processing of Enhanced Thematic Mapper Plus (ETM+) data from Landsat 7. The three programs and their functions are the following:

Briefs : Materials
Plasma CVD of Boron Carbide by Pulsed Secondary Discharge

An improved method of plasma chemical-vapor deposition (CVD) of a thin film of boron carbide has been devised. Boron carbide is useful because it is hard, is electrically insulating, withstands high temperature, and resists chemical attack. Plasma CVD of boron carbide involves the thermal...

Briefs : Mechanical & Fluid Systems
Magnetic Couplings for Gas-Driven Catapults

A proposed magnetic-coupling scheme would afford additional degrees of freedom to optimize the designs of gas-driven catapults or launchers. The scheme could be applied to gas guns in diverse applications, including launching spacecraft or aircraft, propelling various objects at high speeds along the...

Briefs : Mechanical & Fluid Systems
Differential-Pressure Relief Valve

A relief valve has been designed to limit the differential pressure between two fluids that are not allowed to be mixed. This valve offers advantages over both simple check valves and simple relief valves. A simple relief valve vents a fluid at the preset absolute relief pressure, but offers no means for...

Briefs : Mechanical & Fluid Systems
Vortex-Fired Liquid-Fuel Rocket Combustion Chambers

Liquid-fuel rocket engines that utilize vortex flow fields to keep combustion-chamber walls cool have been investigated in computational simulations and experiments. In an engine of this type, the vortex flow establishes radial gradients of pressure and density that cause the lower-density hot...

Briefs : Mechanical & Fluid Systems
Systems for Dynamic Control of Growth of Protein Crystals

Computer-controlled laboratory apparatuses for real-time monitoring and control of the growth of protein crystals are undergoing development. By use of an apparatus of this type, one can monitor and control several parameters that affect the growth of protein crystals; these parameters...

Briefs : Medical
In Situ Activation of Microencapsulated Drugs

In a new method of delivering drugs to target sites in a human body, (1) the drugs would be stored in inactive forms in timed-release microcapsules that would be injected, then (2) the drugs would be activated by exposing the target sites to suitable forms of penetrating energy that could include...

Briefs : Physical Sciences
Spaceborne Telescope for Communication, Ranging, and Imaging

A report describes a program to develop a multi-function telescope to be carried aboard spacecraft of the planned X2000 series of planetary missions. [A related multi-function telescope was described in "Telescope for Imaging and Laser Communication" (NPO-20388), NASA Tech...

Briefs : Physical Sciences
Dislocation-Induced Changes in InxGa1 -xAs Quantum Dots

A report describes an experimental investigation that revealed a previously unknown type of spatial alignment of quantum dots (QDs) in InxGa1 -xAs/GaAs multilayer structures. Multilayer arrays of QDs (in the form of nanometer-sized...

Briefs : Physical Sciences
Solitons on WDM Beams in a Nonlinear Optical Fiber

This paper sets the ultimate limit on the maximum amount of optical data pulses that can be sent through a single fiber in a given period under the wavelength-division-multiplexed (WDM) format. The discovery in 1973 that optical soliton on a single wavelength beam can exist in fiber is one of...