Magazine

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Briefs: Physical Sciences
Pixelized Device Control Actuators for Large Adaptive Optics
A fully integrated, compact, adaptive space optic mirror assembly has been developed, incorporating new advances in ultralight, high- performance composite mirrors. The composite mirrors use Q-switch matrix architecture- based pixelized control (PMN-PT) actuators, which achieve high-...
Briefs: Semiconductors & ICs
Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as prototype...
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Briefs: Semiconductors & ICs
Closely following the development reported in the article, "Low-Noise MMIC Amplifiers for 120 to 180 GHz" (NPO-42783), three new monolithic microwave integrated circuit (MMIC)...
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Briefs: Electronics & Computers
Some logic circuits have been built and demonstrated to work substantially as intended, all as part of a continuing effort to exploit the high degrees of design flexibility and functionality of the...
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Briefs: Electronics & Computers
It is possible to synthesize a voltage-controlled negative-differential-resistance (NDR) device or circuit by use of a pair of complementary G4FETs (four-gate field-effect...
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Briefs: Materials
Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer
A film-growth process was developed for polycrystalline mercuric iodide that creates cost-effective, large-area detectors for high-energy charged-particle detection. A material, called a barrier film, is introduced onto the substrate before the normal mercuric iodide film growth...
Briefs: Physical Sciences
An improved method of designing complexly shaped inflatable shells to be assembled from gores was conceived for original application to the inflatable outer shell of a developmental...
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Briefs: Electronics & Computers
Electrically variable or programmable capacitors based on the unique properties of thin perovskite films are undergoing development. These capacitors show promise of overcoming two...
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Briefs: Electronics & Computers
Vector modulators are used to impose baseband modulation on RF signals, but non- ideal behavior limits the overall performance. The non-ideal behavior of the vector modulator is compensated...
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Briefs: Green Design & Manufacturing
Using Ozone To Clean and Passivate Oxygen-Handling Hardware
A proposed method of cleaning, passivating, and verifying the cleanliness of oxygen-handling hardware would extend the established art of cleaning by use of ozone. As used here, “cleaning” signifies ridding all exposed surfaces of combustible (in particular, carbon-based) contaminants....
Briefs: Materials
Two-Piece Screens for Decontaminating Granular Material
Two-piece screens have been designed specifically for use in filtering a granular material to remove contaminant particles that are significantly wider or longer than are the desired granules. In the original application for which the two-piece screens were conceived, the granular material is...
Briefs: Materials
Rectangular-waveguide inserts that are made of non-ferromagnetic metals and are sized and shaped to function as notch filters have been conceived as reference standards for use in the...
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Briefs: Mechanical & Fluid Systems
Ultra-Large Solar Sail
UltraSail is a next- generation ultra-large (km2 class) sail system. Analysis of the launch, deployment, stabilization, and control of these sails shows that high-payload-mass fractions for interplanetary and deep-space missions are possible. UltraSail combines propulsion and control systems developed for formation- flying...
Briefs: Mechanical & Fluid Systems
Teamed Robots for Exploration and Science in Steep Areas (TRESSA) is a system of three autonomous mobile robots that cooperate with each other to enable scientific exploration of steep...
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Briefs: Mechanical & Fluid Systems
Assemblies of tanks having shapes that conform to each other and/or conform to other proximate objects have been investigated for use in storing fuels and oxidizers in small available spaces in upper stages of...
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Briefs: Mechanical & Fluid Systems
Microfluidic Pumps Containing Teflon® AF Diaphragms
Microfluidic pumps and valves based on pneumatically actuated diaphragms made of Teflon® AF polymers are being developed for incorporation into laboratory-on-a-chip devices that must perform well over temperature ranges wider than those of prior diaphragm-based microfluidic pumps and valves....
Briefs: Physical Sciences
The concept of a transparent conveyor of small loose dielectric particles or small amounts of dielectric liquids has emerged as an outgrowth of an effort to develop efficient, reliable...
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Briefs: Physical Sciences
The multi-cone model is a computational model for estimating ionospheric delays of Global Positioning System (GPS) signals. It is a direct descendant of the conical-domain model, which was...
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Briefs: Physical Sciences
Progress Toward a Compact, Highly Stable Ion Clock
There was an update on the subject of two previous NASA Tech Briefs articles: “Compact, Highly Stable Ion Clock” (NPO-43075), Vol. 32, No. 5 (May 2008), page 63; and “Neon as a Buffer Gas for a Mercury-Ion Clock” (NPO-42919), Vol. 32, No. 7 (July 2008), page 62. To recapitulate: A...
Briefs: Physical Sciences
Systematic studies have been performed on the sensitivity of GaN HEMT (high electron mobility transistor) sensors using various gate electrode designs and operational parameters. The results here show...
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Briefs: Physical Sciences
On the Divergence of the Velocity Vector in Real-Gas Flow
A theoretical study was performed addressing the degree of applicability or inapplicability, to a real gas, of the occasionally stated belief that for an ideal gas, incompressibility is synonymous with a zero or very low Mach number. The measure of compressibility used in this study is the...
Briefs: Information Technology
Integrated Risk and Knowledge Management Program — IRKM-P
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...
Briefs: Information Technology
A method of constructing certain low-density parity-check (LDPC) codes by use of relatively simple loop-free coding modules has been developed. The subclasses of LDPC codes to which the...
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Briefs: Information Technology
Low-density parity-check (LDPC) codes characterized by minimum Hamming distances proportional to block sizes have been demonstrated. Like the codes mentioned in the immediately...
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Briefs: Electronics & Computers
MMICs With Radial Probe Transitions to Waveguides
A document presents an update on the innovation reported in “Integrated Radial Probe Transition From MMIC to Waveguide” (NPO-43957), NASA Tech Briefs Vol. 31, No. 5 (May 2007), page 38. To recapitulate: To enable operation or testing of a monolithic microwave integrated circuit (MMIC), it is...
Briefs: Electronics & Computers
Tests of Low-Noise MMIC Amplifier Module at 290 to 340 GHz
A document presents data from tests of a low-noise amplifier module operating in the frequency range from 290 to 340 GHz — said to be the highest-frequency low-noise, solid-state amplifier ever developed. The module comprised a three-stage monolithic microwave integrated circuit (MMIC)...
Briefs: Information Technology
Extending Newtonian Dynamics to Include Stochastic Processes
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...
Eye on Innovation: Manufacturing & Prototyping
Given the current economic conditions, companies must continue to deliver existing products as they develop the products of tomorrow, without increasing the engineering...
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Briefs: Physical Sciences
The acronym “CHAMP” (signifying “camera, hand lens, and microscope”) denotes any of several proposed optoelectronic instruments that would be capable of color imaging at working distances that...
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