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Briefs: Photonics/Optics
An atom laser now undergoing development simultaneously generates two pulsed beams of correlated 87Rb atoms. (An atom laser is a source of atoms in beams characterized by coherent matter waves,...
Briefs: Photonics/Optics
A rugged, tunable extended-cavity diode laser (ECDL) has been developed to satisfy stringent requirements for frequency stability, notably including low sensitivity to vibration. This laser is...
Briefs: Physical Sciences
Balloon for Long-Duration, High-Altitude Flight at Venus
A document describes a 5.5-m-diameter, helium-filled balloon designed for carrying a scientific payload having a mass of 44 kg for at least six days at an altitude of about 55 km in the atmosphere of Venus. The requirement for floating at nearly constant altitude dictates the choice of a...
Briefs: Electronics & Computers
Wide-Temperature-Range Integrated Operational Amplifier
A document discusses a silicon-oninsulator (SOI) complementary metal oxide/ semiconductor (CMOS) integrated- circuit operational amplifier to be replicated and incorporated into sensor and actuator systems of Mars- explorer robots. This amplifier is designed to function at a supply potential...
Briefs: Medical
Wearable Environmental and Physiological Sensing Unit
The wearable environmental and physiological sensing unit (WEPS) is a prototype of systems to be worn by emergency workers (e.g., firefighters and members of hazardous-material response teams) to increase their level of safety. The WEPS includes sensors that measure a few key physiological and...
Briefs: Physical Sciences
A focus-diverse phase-retrieval algorithm has been shown to perform adequately for the purpose of image-based wavefront sensing when (1) broadband light (typically spanning the visible...
Briefs: Physical Sciences
A phase-diverse iterative-transform phase-retrieval algorithm enables high-spatial-frequency, high-dynamic-range, image-based wavefront sensing. [The terms "phase-diverse," "phase...
Briefs: Physical Sciences
In an alternative hardware design for an apparatus used in image-based wavefront sensing, defocus diversity is introduced by means of fixed lenses that are mounted in a filter wheel (see...
Briefs: Electronics & Computers
Smooth phase interpolated keying (SPIK) is an improved method of computing smooth phase-modulation waveforms for radio communication systems that convey digital information. SPIK is applicable to a variety of...
Briefs: Electronics & Computers
Maintaining Stability During a Conducted-Ripple EMC Test
An improved technique, and electronic circuitry to implement the technique, have been developed for a military-standard electromagnetic-compatibility (EMC) test in which one analyzes susceptibility to low-frequency ripple conducted into the equipment under test via a DC power line. In the...
Briefs: Electronics & Computers
Photodiode Preamplifier for Preamplifier for Weak Signals
An improved preamplifier circuit has been designed for processing the output of an avalanche photodiode (APD) that is used in a high-resolution laser ranging system to detect laser pulses returning from a target. The improved circuit stands in contrast to prior such circuits in which the APD...
Briefs: Electronics & Computers
Advanced High-Definition Video Cameras
A product line of high-definition color video cameras, now under development, offers a superior combination of desirable characteristics, including high frame rates, high resolutions, low power consumption, and compactness. Several of the cameras feature a 3,840 × 2,160-pixel format with progressive scanning...
Briefs: Semiconductors & ICs
Circuit for Full Charging of Series Lithium-Ion Cells
An advanced charger has been proposed for a battery that comprises several lithium-ion cells in series. The proposal is directed toward charging the cells in as nearly an optimum manner as possible despite unit-to-unit differences among the nominally identical cells.
Briefs: Semiconductors & ICs
Analog Nonvolatile Computer Memory Circuits
In nonvolatile random-access memory (RAM) circuits of a proposed type, digital data would be stored in analog form in ferroelectric field-effect transistors (FFETs). This type of memory circuit would offer advantages over prior volatile and nonvolatile types:
Briefs: Software
World Wind 3D Earth Viewing
World Wind allows users to zoom from satellite altitude down to any place on Earth, leveraging high-resolution LandSat imagery and SRTM (Shuttle Radar Topography Mission) elevation data to experience Earth in visually rich 3D. In addition to Earth, World Wind can also visualize other planets, and there are already...
Briefs: Software
JavaGenes Molecular Evolution
JavaGenes is a general-purpose, evolutionary software system written in Java. It implements several versions of a genetic algorithm, simulated annealing, stochastic hill climbing, and other search techniques. This software has been used to evolve molecules, atomic force field parameters, digital circuits, Earth...
Briefs: Materials
Accounting for Uncertainties in Strengths of SiC MEMS Parts
A methodology has been devised for accounting for uncertainties in the strengths of silicon carbide structural components of microelectromechanical systems (MEMS). The methodology enables prediction of the probabilistic strengths of complexly shaped MEMS parts using data from tests of...
Briefs: Materials
Lithium Dinitramide as an Additive in Lithium Power Cells
Lithium dinitramide, LiN(NO2)2 has shown promise as an additive to nonaqueous electrolytes in rechargeable and non-rechargeable lithium-ion-based electrochemical power cells. Such non-aqueous electrolytes consist of lithium salts dissolved in mixtures of organic ethers, esters, carbonates,...
Briefs: Materials
Ion-conducting polymers that are hybrids of organic and inorganic moieties and that are suitable for forming into solid electrolyte membranes have been invented in an effort to improve upon the...
Briefs: Materials
MoO3 has shown promise as a cathode material that can extend the upper limit of operating temperature of rechargeable lithium thin-film electrochemical cells. Cells of this type are...
Briefs: Mechanical & Fluid Systems
A streamliner motorcycle designed and built by Sierra Design Engineering and BUB Enterprises achieved a new world-record speed of 350.884 miles per hour last year at the Bonneville Salt...
Briefs: Manufacturing & Prototyping
A counterrotating-shoulder mechanism has been proposed as an alternative to the mechanism and fixtures used in conventional friction stir welding. The mechanism would internally react...
Briefs: Manufacturing & Prototyping
A method of detecting mechanical failure induced by variation in temperature at an adhesive bond between two materials that have different coefficients of thermal expansion (CTEs)...
Briefs: Medical
Antibodies that bind to preselected regions of the urokinase molecule have been developed. These antibodies can be used to measure small quantities of each of three molecular forms of urokinase that...
Briefs: Medical
Understanding and Counteracting Fatigue in Flight Crews
The materials included in the collection of documents describe the research of the NASA Ames Fatigue Countermeasures Group (FCG), which examines the extent to which fatigue, sleep loss, and circadian disruption affect flight-crew performance. The group was formed in 1980 — in response to a...
Briefs: Physical Sciences
A system of active optics that includes a wavefront sensor and a deformable mirror has been demonstrated to be an effective means of partly correcting wavefront aberrations...
Briefs: Photonics/Optics
Recirculation of Laser Power in an Atomic Fountain
A new technique for laser-cooling atoms in a cesium atomic fountain frequency standard relies on recirculation of laser light through the atom-collection region of the fountain. The recirculation, accomplished by means of reflections from multiple fixed beam-splitter cubes, is such that each of two...
Briefs: Photonics/Optics
A simplified method of generating a beam of light having a relatively high value of angular momentum (see figure) involves the use of a compact apparatus consisting mainly of a laser, a...
Briefs: Photonics/Optics
Two interferometric quantum-nondemolition (QND) devices have been proposed: (1) a polarization-independent device and (2) a polarization-preserving device. The...
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