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Developments at the Advanced Design Technologies Testbed

A report presents background and historical information, as of August 1998, on the Advanced Design Technologies Testbed (ADTT) at Ames Research Center. The ADTT is characterized as an activity initiated to facilitate improvements in aerospace design processes; provide a proving ground for product-development methods and computational software and hardware; develop "bridging" methods, software, and hardware that can facilitate integrated solutions to design problems; and disseminate lessons learned to the aerospace and information-technology communities.

Posted in: Information Sciences, Briefs

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Acoustical Applications of the HHT Method

A document discusses applications of a method based on the Huang-Hilbert transform (HHT). The method was described, without the HHT name, in "Analyzing Time Series Using EMD and Hilbert Spectra" (GSC-13817), NASA Tech Briefs, Vol. 24, No. 10 (October 2000), page 63. To recapitulate: The method is especially suitable for analyzing time-series data that represent nonstationary and nonlinear physical phenomena. The method involves the empirical mode decomposition (EMD), in which a complicated signal is decomposed into a finite number of functions, called "intrinsic mode functions" (IMFs), that admit well-behaved Hilbert transforms. The HHT consists of the combination of EMD and Hilbert spectral analysis.

Posted in: Information Sciences, Briefs

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Microstrip Antenna Arrays on Multilayer LCP Substrates

Antennas, feedlines, and switches are embedded in and on flexible sheets. A research and development effort now underway is directed toward satisfying requirements for a new type of relatively inexpensive, lightweight, microwave antenna array and associated circuitry packaged in a thin, flexible sheet that can readily be mounted on a curved or flat rigid or semi-rigid surface. A representative package of this type consists of microwave antenna circuitry embedded in and/or on a multilayer liquid- crystal polymer (LCP) substrate. The circuitry typically includes an array of printed metal microstrip patch antenna elements and their feedlines on one or more of the LCP layer(s). The circuitry can also include such components as electrostatically actuated microelectromechanical systems (MEMS) switches for connecting and disconnecting antenna elements and feedlines. In addition, the circuitry can include switchable phase shifters described below.

Posted in: Semiconductors & ICs, Briefs, TSP

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Detecting Moving Targets by Use of Soliton Resonances

Faint targets moving uniformly would be distinguished from background clutter. A proposed method of detecting moving targets in scenes that include cluttered or noisy backgrounds is based on a soliton-resonance mathematical model. The model is derived from asymptotic solutions of the cubic Schroedinger equation for a one-dimensional system excited by a position-and-time- dependent externally applied potential. The cubic Schroedinger equation has general significance for time-dependent dispersive waves. It has been used to approximate several phenomena in classical as well as quantum physics, including modulated beams in nonlinear optics, and superfluids (in particular, Bose-Einstein condensates). In the proposed method, one would take advantage of resonant interactions between (1) a soliton excited by the position-and-time-dependent potential associated with a moving target and (2) "eigen-solitons," which represent dispersive waves and are solutions of the cubic Schroedinger equation for a time-independent potential.

Posted in: Information Sciences, Briefs, TSP

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Finite-Element Methods for Real-Time Simulation of Surgery

Some accuracy is traded for computational speed. Two finite-element methods have been developed for mathematical modeling of the time-dependent behaviors of deformable objects and, more specifically, the mechanical responses of soft tissues and organs in contact with surgical tools. These methods may afford the computational efficiency needed to satisfy the requirement to obtain computational results in real time for simulating surgical procedures as described in "Simulation System for Training in Laparoscopic Surgery" (NPO-21192) on page 31 in this issue of NASA Tech Briefs.

Posted in: Information Sciences, Briefs, TSP

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Incorporating Intelligent Energy Savings and Predictive Maintenance in a Soft Start

Electric motors consume approximately one quarter of the electricity in the U.S. and are the main motive force in our commercial buildings, industrial facilities, and appliances. Everyone knows reducing energy consumption has become a priority for the U.S. Many new methods of reducing electricity are being considered, including new electric motor efficiency technologies.

Posted in: Features, Motion Control, Articles

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Slide Guide Used in Fluorescence Microscope

In the USA and other developed countries, cancer is responsible for 25% of all deaths. In spite of the most recent advances in cancer research, by far the best curative treatment for the disease is early detection. Such technology revolves around quick identification of malignant cells, necessitating clean, crisp images for oncologists. The CellTracks Analyzer II by Immunicon (Huntington Valley, PA) is a semi-automated fluorescence microscope system used to count and characterize fluorescently labeled cells that are immuno-magnetically selected and aligned. The SEBS-B type miniature slide guide, from NB Corp. of America (Wood Dale, IL), is tapped as part of the microscope’s system of axes.

Posted in: Applications, Motion Control, Application Briefs

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