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Delay banking has been invented to enhance air-traffic management in a way that would increase the degree of fairness in assigning arrival, departure, and en-route delays and trajectory deviations to aircraft impacted by congestion in the national airspace system. In delay banking, an aircraft operator...

A combined frequency- time (CFT) spectral moment estimation technique has been devised for calculating rainfall velocity from measurement data acquired by a nadir-looking spaceborne Doppler weather radar system. Prior spectral moment estimation techniques used for this purpose are based...

Smectic A (SmA) materials can be used in non-mechanical, digital beam deflectors (DBDs) as fillers for passive birefringent prisms based on decoupled pairs of electrically controlled, liquid crystalline polarization rotators, like twisted nematic (TN) cells and passive deflectors. DBDs are used in...

Resonators usually are characterized with two partially dependent values: finesse (ℱ) and quality factor (Q). The finesse of an empty Fabry-Perot (FP) resonator is defined solely by the quality of its mirrors and is calculated asℱ = πR1/2/(1 – R).

USMC6 is a Fortran 90 computer program for post-processing in support of visualization of flows simulated by computational fluid dynamics (CFD). The name "USMC6" is partly an abbreviation of "TetrUSS — USM3D Solution Cutter," reflecting its origin as a post-processor for use with USM3D...

This software solves the Navier- Stokes equations for the incompressible driven cavity flow problem. The code uses second-order finite differencing on a staggered grid using the Chorin projection method. The resulting intermediate Poisson equation is efficiently solved using the fast Fourier...

This is an extension of the Flow Solver for Incompressible 2-D Drive Cavity software described in the preceding article. It solves the Navier- Stokes equations for incompressible flow using finite differencing on a uniform, staggered grid. There is a runtime choice of either central differencing or...

Cockpit Avionics Prototyping Environment (CAPE) is a computer program that simulates the functions of proposed upgraded avionics for a space shuttle. In CAPE, pre-existing space-shuttle-simulation programs are merged with a commercial-off-the-shelf (COTS) display-development program, yielding a...

Single-event upsets (SEUs) or "bitflips" are computer memory errors caused by radiation. BITFLIPS (Basic Instrumentation Tool for Fault Localized Injection of Probabilistic SEUs) is a computer program that deliberately injects SEUs into another computer program, while the latter is...

A computer program estimates the relative positions and orientations of two space structures from data on the angular positions and distances of fiducial objects on one structure as measured by a target-tracking electronic camera and laser range finders on another structure. The program...

A computer program related to the one described in the immediately preceding article estimates the relative position of two space structures that are hinged to each other. The input to the program consists of time-series data on distances, measured by two range finders at different...

The Commercial Modular Aero- Propulsion System Simulation (CMAPSS) is a computer program for simulating transient operation of a commercial turbofan engine that can generate as much as 90,000 lb (≈0.4 MN) of thrust. It includes a power-management system that enables simulation of open- or...