Briefs: Physical Sciences
Doping-Induced Interband Gain in InAs/AlSb Quantum Wells

A paper describes a computational study of effects of doping in a quantum well (QW) comprising a 10-nm-thick layer of InAs sandwiched between two 21-nm-thick AlSb layers.

Briefs: Software
Tools for Designing and Analyzing Structures

Structural Design and Analysis Toolset is a collection of approximately 26 Microsoft Excel spreadsheet programs, each of which performs calculations within a different subdiscipline of structural design and analysis.

Briefs: Software
Interactive Display of Scenes With Annotations

ThreeDView was developed primarily as a component of the Science Activity Planner (SAP) software, wherein it is to be used to display annotated images of terrain acquired by exploratory robots on Mars and possibly other remote planets. The images can be generated from sets of multiple-texture image...

Briefs: Software
Solving Common Mathematical Problems

Mathematical Solutions Toolset is a collection of five software programs that rapidly solve some common mathematical problems.

Briefs: Software
Tools for Basic Statistical Analysis

Statistical Analysis Toolset is a collection of eight Microsoft Excel spreadsheet programs, each of which performs calculations pertaining to an aspect of statistical analysis.

Briefs: Test & Measurement
Program Calculates Forces in Bolted Structural Joints

A mathematical model of a structure is first created by approximating its load-bearing members with representative finite elements, then NASTRAN calculates the forces and moments that each finite element contributes to grid points located throughout the structure. The user selects the finite...

Since the 1930s, synchrotrons have become essential in the widely diverse fields of scientific research and engineering development, including chemistry, biology, material...

Briefs: Test & Measurement
Integrated Structural Analysis and Test Program

An integrated structural-analysis and structure-testing computer program is being developed in order to:

Automate repetitive processes in testing and analysis; Accelerate pre-test analysis; Accelerate reporting of tests; Facilitate planning of tests; Improve execution of tests; Create a...

Organic light-emitting diode (OLED) technology comprises organic thin films that, when placed between two conductors, can serve as a display. This technology requires very...

Briefs: Physical Sciences
Using Laser-Induced Incandescence To Measure Soot in Exhaust

An instrumentation system exploits laser-induced incandescence (LII) to measure the concentration of soot particles in an exhaust stream from an engine, furnace, or industrial process that burns hydrocarbon fuel. In comparison with LII soot-concentration-measuring systems that have...

This enhanced illumination design and analysis program, called LightTools® 5.1, enables easy and accurate modeling of sophisticated backlights for flat panel displays....

Although battery-powered computer based instruments are commonplace, they typically lack powerful processors capable of running sophisticated Windows 2000/XP-level...

Briefs: Electronics & Computers
Indoor Navigation Using Direction Sensor and Beacons

A system for indoor navigation of a mobile robot includes (1) modulated infrared beacons at known positions on the walls and ceiling of a room and (2) a cameralike sensor, comprising a wide angle lens with a position-sensitive photodetector at the focal plane, mounted in a known position and...

Briefs: Electronics & Computers
Automated Analysis, Classification, and Display of Waveforms

A computer program partly automates the analysis, classification, and display of waveforms represented by digital samples. In the original application for which the program was developed, the raw waveform data to be analyzed by the program are acquired from space shuttle auxiliary...

Briefs: Electronics & Computers
Fast-Acquisition/Weak-Signal-Tracking GPS Receiver for HEO

A report discusses the technical background and design of the Navigator Global Positioning System (GPS) receiver — a radiation-hardened receiver intended for use aboard spacecraft. Navigator is capable of weak signal acquisition and tracking as well as much faster acquisition of...

Briefs: Electronics & Computers
Signal Design for Improved Ranging Among Multiple Transceivers

"Ultra-BOC" (where "BOC" signifies "binary offset carrier") is the name of an improved generic design of microwave signals to be used by a group of spacecraft flying in formation to measure ranges and bearings among themselves and to exchange telemetry needed for these measurements....

Briefs: Electronics & Computers
High-Rate Digital Receiver Board

A high-rate digital receiver (HRDR) implemented as a peripheral component interface (PCI) board has been developed as a prototype of compact, general- purpose, inexpensive, potentially mass-producible data-acquisition interfaces between telemetry systems and personal computers. The installation of this board in a...

Virtually all businesses and industries are vulnerable to electric power disturbances such as outages, sags, swells, and harmonics. These problems are less of an...

Briefs: Mechanical & Fluid Systems
Carbon-Fiber Brush Heat Exchangers

Velvetlike and brushlike pads of carbon fibers have been proposed for use as mechanically compliant, highly thermally conductive interfaces for transferring heat. A pad of this type would be formed by attaching short carbon fibers to either or both of two objects that one desires to place in thermal contact...

An algorithm computes the velocity of wind from the readings of an instrument like the one described in "Three-Dimensional Venturi Sensor for Measuring Extreme Winds"...

Briefs: Information Technology
Feature-Identification and Data-Compression Software

A report discusses the continuing development of Windows Interface for Nominal Displacement Selection (WINDS), a computer program for automated analysis of images of the Sun and planets acquired by scientific instruments aboard spacecraft. WINDS is intended to afford capabilities for...

Briefs: Information Technology
Masked Proportional Routing

Masked proportional routing is an improved procedure for choosing links between adjacent nodes of a network for the purpose of transporting an entity from a source node (“A”) to a destination node (“B”)....

A class of end-cap compounds that increase the thermo-oxidative stability of polyimides of the polymerization of monomeric reactants (PMR) type has been extended. In addition, an...

Dendrimeric reporter compounds have been invented for use in sensing and amplifying electrochemical signals from molecular recognition events that involve many chemical and biological entities. These...

Briefs: Materials
Precious-Metal Salt Coatings for Detecting Hydrazines

Substrates coated with a precious metal salt KAuCl4 have been found to be useful for detecting hydrazine vapors in air at and above a concentration of the order of 0.01 parts per million (ppm). Upon exposure to air containing a sufficient amount of hydrazine for a sufficient time, the coating...

Nanocarpets — that is, carpets of carbon nanotubes — are undergoing development as means of trapping microscopic particles for scientific analysis. Examples of such particles include...

Briefs: Mechanical & Fluid Systems
Alternative Attitude Commanding and Control for Precise Spacecraft Landing

A report proposes an alternative method of control for precision landing on a remote planet. In the traditional method, the attitude of a spacecraft is required to track a commanded translational acceleration vector, which is generated at each time step by solving a...

Briefs: Physical Sciences
Helicity in Supercritical O₂/H₂ and C₇H₁₆/N₂ Mixing Layers

This report describes a study of databases produced by direct numerical simulation of mixing layers developing between opposing flows of two fluids under supercritical conditions, the purpose of the study being to elucidate chemical species-specific aspects of turbulence,...

A proposed toroidal or disklike dielectric optical resonator (dielectric optical cavity) would be made of an optically nonlinear material and would be optimized for use in parametric...

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