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Self-Supervised Dynamical Systems

Mathematical models describe coupled motor and mental dynamics. Some progress has been made in a continuing effort to develop mathematical models of the behaviors of multi- agent systems known in biology, economics, and sociology (e.g., systems ranging from single or a few biomolecules to many interacting higher organisms). This effort at an earlier stage was reported in "Characteristics of Dynamics of Intelligent Systems" (NPO- 21037), NASA Tech Briefs, Vol. 26, No. 12 (December 2002), page 48.

Posted in: Information Sciences, Briefs, TSP

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Integrated Formulation of Beacon-Based Exception Analysis for Multimissions

BEAM has become a broadly applicable, highly capable means of automated diagnosis. Further work on beacon-based exception analysis for multimissions (BEAM), a method of real-time, automated diagnosis of a complex electromechanical systems, has greatly expanded its capability and suitability of application. This expanded formulation, which fully integrates physical models and symbolic analysis, is described architecturally in the figure.

Posted in: Information Sciences, Briefs, TSP

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Compact System Detects Potentially Explosive Gas Mixtures

This system can be used in environments too severe for conventional leak detectors. The figure depicts selected aspects of a "smart" microelectronic-based hazardous-gas-detection system that simultaneously measures concentrations of hydrogen and oxygen. Unlike conventional gas-leak-detection systems built around mass spectrometers, this system is not restricted to operation in relatively mild and controlled laboratory or shop environments; instead, this system can operate over a range of temperatures and pressures. Also, in comparison with conventional mass-spectrometer-based leak-detection systems, this system is more robust and compact, weighs less, and consumes less power.

Posted in: Physical Sciences, Briefs, TSP

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Artifacts for Calibration of Submicron Width Measurements

Dimensional tolerances as small as 1 nm should be possible. Artifacts that are fabricated with the help of molecular-beam epitaxy (MBE) are undergoing development for use as dimensional calibration standards with submicron widths. Such standards are needed for calibrating instruments (principally, scanning electron microscopes and scanning probe microscopes) for measuring the widths of features in advanced integrated circuits. Dimensional calibration standards fabricated by an older process that involves lithography and etching of trenches in (110) surfaces of single-crystal silicon are generally reproducible to within dimensional tolerances of about 15 nm. It is anticipated that when the artifacts of the present type are fully developed, their critical dimensions will be reproducible to within 1 nm. These artifacts are expected to find increasing use in the semiconductor-device and integrated-circuit industries as the width tolerances on semiconductor devices shrink to a few nanometers during the next few years.

Posted in: Information Sciences, Briefs, TSP

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Designing Facilities for Collaborative Operations

A methodology is emerging from efforts to design a mission operations facility. A methodology for designing operational facilities for collaboration by multiple experts has begun to take shape as an outgrowth of a project to design such facilities for scientific operations of the planned 2003 Mars Exploration Rover (MER) mission. The methodology could also be applicable to the design of military "situation rooms" and other facilities for terrestrial missions.

Posted in: Information Sciences, Briefs, TSP

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Optimal Feedback Control of Thermal Networks

A systematic approach to design has been devised. An improved approach to the mathematical modeling of feedback control of thermal networks has been devised. Heretofore software for feedback control of thermal networks has been developed by time-consuming trial-and-error methods that depend on engineers' expertise. In contrast, the present approach is a systematic means of developing algorithms for feedback control that is optimal in the sense that it combines performance with low cost of implementation. An additional advantage of the present approach is that a thermal engineer need not be expert in control theory.

Posted in: Information Sciences, Briefs, TSP

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"Virtual Cockpit Window" for a Windowless Aerospacecraft

A software system processes navigational and sensory information in real time to generate a three- dimensional- appearing image of the external environment for viewing by crewmembers of a windowless aerospacecraft. The design of the particular aerospacecraft (the X-38) is such that the addition of a real transparent cockpit window to the airframe would have resulted in unacceptably large increases in weight and cost.

Posted in: Information Sciences, Briefs

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