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Active Aircraft Pylon Noise Control System
Unmanned Aerial Systems Traffic Management
Method of Bonding Dissimilar Materials
Sonar Inspection Robot System
Applying the Dynamic Inertia Measurement Method to Full-Scale Aerospace Vehicles
Method and Apparatus for Measuring Surface Air Pressure
Fully Premixed, Low-Emission, High-Pressure, Multi-Fuel Burner
Self-Healing Wire Insulation
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Report on User's Guidefor Monthly Vector Wind Profile Model

A report briefly describes a user's guide for a computer program that constructs vector wind profiles on the basis of a statistical model. The monthly vector wind profiles are meant to be used (1) to estimate wind-dispersion-related dispersions of critical aerodynamic loads and corresponding aerospace-ascent-vehicle design parameters and (2) to analyze effects of monthly wind-profile dispersions on ascent trajectories and to design ascent autopilot systems to correct for these effects. The user's guide is also said to list output data to aid the user in the verification of test output.

Posted in: Briefs, TSP, Physical Sciences

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Sizes of Surface and Capped InxGa1-xAs/GaAs Quantum Dots

A report describes an experimental study of the sizes and concentrations of capped (buried) and surface In0.6Ga0.4As/GaAs quantum dots that were grown by metal-organic vapor deposition under the same conditions except for the inclusion or exclusion of capping. [InxGa1-xAs/GaAs quantum dots are lens-shaped islands (typically a few nanometers thick and tens of nanometers in diameter) of InxGa1-xAs grown on a GaAs substrate. As used here, "capping" signifies the growth of a layer of GaAs over the InxGa1-xAs islands.] In the experiments, the sizes of the capped In0.6Ga0.4As/GaAs islands were measured by transmission electron microscopy (TEM).

Posted in: Briefs, TSP, Physical Sciences

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Fuel Cell Would Generate Power From Martian Atmosphere

A report proposes the development of a thin-film fuel cell that would generate electric power from two minor constituents of the Martian atmosphere — O2 and CO. These compounds are generated continuously by photolysis of CO2, the major constituent. The fuel cell would include a cathode and an anode made of catalysts suitable for the selective low-temperature electrochemical reduction of O2 and oxidation of CO, respectively. It would also include a hygroscopic gel electrolyte.

Posted in: Briefs, TSP, Physical Sciences

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Improved Automate System for Transferring Liquid Helium

Consumption of liquid helium would be reduced by optimizing use of vapor for precooling.An improved automated system for transferring liquid helium from a supply tank to an end-use cryostat has been proposed. Like automated systems developed previously for the same purpose, this system would reduce the time that must be spent by technicians in replenishing cryostats in equipment required to operate for times longer than cryostat holding times. However, relative to prior automated liquid-helium-transfer systems, this system would operate in a more nearly optimum manner so as to reduce the consumption of liquid helium. Examples of equipment with which this system could be used include apparatuses for long-duration scientific experiments and large cooled electromagnets in medical imaging systems

Posted in: Briefs, Physical Sciences

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Algorithm for Computing Dynamics of Molecules

Equations of motion are solved more efficiently.The Newton-Euler Inverse Mass Operator (NEIMO) algorithm and software that implements the algorithm have been developed to reduce the amount of time needed to perform computational simulations of the dynamics of macromolecules. The NEIMO algorithm and the associated software are intended, in particular, for simulations of molecular motions at a space-time mesoscale, defined here as a length scale ranging from nanometers to micrometers and a time scale ranging from microseconds to milliseconds. Older molecular-dynamics algorithms and computer programs are not suitable for mesoscale simulations because they were formulated for the time scales, of the order of a microsecond or less, characteristic of such high-frequency degrees of freedom as stretching of molecular bonds.

Posted in: Briefs, TSP, Physical Sciences

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Improving Thin Foil X-Ray Mirrors

Resolution and diameter would be increased.A proposal has been made to develop improved thin foil, replicated conical mirrors for use in x-ray astrophysics. In the NASA astrophysical programs in which such mirrors are used, they are required to be lightweight, and to offer moderate angular resolution and high throughput to afford required sensitivity in the photon-energy band from 0.1 to 20 keV. In the proposed improvement program, emphasis would be placed on increasing resolution and diameter:

Posted in: Briefs, Physical Sciences

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First-Generation Integrated Free-Flying Micro-Spacecraft

The concept of free-flying micro-spacecraft was to develop a miniature spacecraft system fully integrated with a scientific sensor. A fleet of such tiny spacecraft would be deployed in space for multi-probe measurements of a three-dimensional phenomenon and to separate the spatial/temporal variations of that phenomenon. They would measure a parameter of interest, process the data onboard, and communicate the data in real time.

Posted in: Briefs, TSP, Physical Sciences

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