This algorithm provides a new way to improve the accuracy and asymptotic behavior of a low-dimensional system based on the proper orthogonal decomposition (POD). Given a data set representing the evolution of a system of partial differential equations (PDEs), such as the Navier-Stokes equations...

A method of parameterizing the coefficients of a dynamical system based of a proper orthogonal decomposition (POD) representing the flow dynamics of a viscous fluid has been introduced. (A brief description of POD is presented in the immediately preceding article.) The present...

The Tin Whisker Metal Vapor Arcing Risk Assessment Tool has been designed to evaluate the risk of metal vapor arcing and to help facilitate a decision toward a researched risk disposition. Users can evaluate a system without having to open up the hardware. This process allows for investigating components at...

A two-stage predictive method was developed for lossless compression of calibrated hyperspectral imagery. The first prediction stage uses a conventional linear predictor intended to exploit spatial and/or spectral dependencies in the data. The compressor tabulates counts of the...

Confidence-based Feature Acquisition (CFA) is a novel, supervised learning method for acquiring missing feature values when there is missing data at both training (learning) and test (deployment) time. To train a machine learning classifier, data is encoded with a series of input features describing each item....

Software has been developed to implement the ICER-3D algorithm. ICER-3D effects progressive, threedimensional (3D), wavelet-based compression of hyperspectral images. If a compressed data stream is truncated, the progressive nature of the algorithm enables reconstruction of hyperspectral data at...

A context-modeling subalgorithm has been developed as part of an algorithm that effects three-dimensional (3D) wavelet-based compression of hyperspectral image data. The context-modeling subalgorithm, hereafter denoted the context modeler, provides estimates of probability...

An efficient bit-interleaving algorithm for a turbo encoder differs from prior such algorithms in that it does not require memory to store permutation mappings and can work with constituent decoders that produce multiple bit reliabilities per decoding stage. The algorithm can be implemented in...

This new generalized approach to prognostics can provide an automated early failure prediction of an engineering system or its components, often in time to prevent occurrence of hard failures. This approach has been demonstrated in a proof-of-concept software prototype, shown to accurately...

A genetic programming (GP)-based, nonlinear modeling structure relates soil moisture with synthetic-apertureradar (SAR) images to present representative soil moisture estimates at the watershed scale. Surface soil moisture measurement is difficult to obtain over a large area due to a...

This work extends the lossless data compression technique described in “Fast Lossless Compression of Multispectral-Image Data,” (NPO- 42517) NASA Tech Briefs, Vol. 30, No. 8 (August 2006), page 26. The original technique was extended to include a...

An algorithm has been devised for predicting the behaviors of sparsely spatially distributed particles impinging on a solid surface in a rarefied atmosphere. Under the stated conditions, prior particle-transport models in which (1) dense distributions of particles are treated as continuum...

A portable system of electromechanical and electronic hardware and documentation has been developed as an automated means of instructing technicians in matters of safety and quality. The system enables elimination of most of the administrative tasks associated with traditional training. Customized, performance-...

A physical-based simulation has been developed for the Mars Exploration Rover (MER) mission that applies a slope-induced wheel-slippage to the rover location estimator. Using the digital elevation map from the stereo images, the computational method resolves the quasi-dynamic equations of motion that...

The Supply-Chain Optimization Tem - plate (SCOT) is an instructional guide for identifying, evaluating, and optimizing (including re-engineering) aerospace-oriented supply chains. The SCOT was derived from the Supply Chain Council’s Supply-Chain Operations Reference (SCC SCOR) Model, which is more generic and...

A method of quickly approximating the distance between two objects (one smaller, regarded as a point; the other larger and complexly shaped) has been devised for use in computationally simulating motions of the objects for the purpose of planning the motions to prevent collisions. The method is...

A document discusses the development of a finite element model for describing thermal transport through microcalorimeter arrays in order to assist in heat-sinking design. A fabricated multiabsorber transition edge sensor (PoST) was designed in order to reduce device wiring density by a factor of four.

Progressive Classification Using Support Vector MachinesAn algorithm for progressive classification of data, analogous to progressive rendering of images, makes it possible to compromise between speed and accuracy. This algorithm uses support vector machines (SVMs) to classify data. An SVM is...

A simple 2D M×N matrix involving sample preparation enables the microanalyst to peer below the noise floor of element percentages reported by the SEM/EDX (scanning electron microscopy/energy dispersive x-ray) analysis, thus yielding more meaningful...

A short document discusses the general problem of mathematical modeling of the three-dimensional rotational dynamics of rigid bodies and of the use of Euler parameters to eliminate the singularities occasioned by the use of Euler angles in such modeling. The document goes on to characterize a Hamiltonian...

An improved active learning method has been devised for training data classifiers. One example of a data classifier is the algorithm used by the United States Postal Service since the 1960s to recognize scans of handwritten digits for processing zip codes. Active learning algorithms enable rapid training...

An algorithm for progressive classification of data, analogous to progressive rendering of images, makes it possible to compromise between speed and accuracy. This algorithm uses support vector machines (SVMs) to classify data. An SVM is a machine learning algorithm that builds a mathematical...

A Shack-Hartmann sensor (SHS) is an optical instrument consisting of a lenslet array and a camera. It is widely used for wavefront sensing in optical testing and astronomical adaptive optics. The camera is placed at the focal point of the lenslet array and...

A paper presents further results of continuing research reported in several previous NASA Tech Briefs articles, the two most recent being “Stochastic Representations of Chaos Using Terminal Attractors” (NPO-41519), [Vol. 30, No. 5 (May 2006), page 57] and “Physical Principle for...

The NASA Exploration Systems Mission Directorate (ESMD) IRKM-P tightly couples risk management and knowledge management processes and tools to produce an effective “modern” work environment. IRKM-P objectives include: (1) to learn lessons from past and current programs (Apollo, Space...