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Briefs: Electronics & Computers
A breadboard version of a transmitter for radio communication at a carrier frequency of 32 GHz (which is in the Ka band) utilizes a vector modulator operating at a carrier frequency of...
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Briefs: Electronics & Computers
A circuit that can function as a phase switch, frequency mixer, or frequency multiplier operates over a broad frequency range in the vicinity of 100 GHz. Among the most notable...
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Briefs: Electronics & Computers
SiC Optically Modulated Field-Effect Transistor
An optically modulated field-effect transistor (OFET) based on a silicon carbide junction field-effect transistor (JFET) is under study as, potentially, a prototype of devices that could be useful for detecting ultraviolet light. The SiC OFET is an experimental device that is one of several devices,...
Briefs: Manufacturing & Prototyping
Systems requirements for complex spacecraft drive design requirements that lead to structures, components, and/or enclosures of a multi-material and multifunctional design. The...
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Briefs: Manufacturing & Prototyping
Wick structures fabricated by machining of titanium porous material are essential components of lightweight titanium/ water heat pipes of a type now being developed for operation at temperatures up to...
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Briefs: Materials
Gadolinia-doped ceria, or GDC, (Gd0.4Ce0.6O2–δ, where the value of δ in this material varies, depending on the temperature and oxygen concentration in the atmosphere in which it is...
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Briefs: Energy
A proposed system for exploiting the ocean thermal gradient to generate power would be based on the thawing-expansion/ freezing-contraction behavior of a wax or perhaps another suitable phase-change...
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Briefs: Unmanned Systems
A proposed system would exploit the ocean thermal gradient for recharging the batteries in a battery-powered unmanned underwater vehicle [UUV (essentially, a small exploratory submarine...
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Briefs: Mechanical & Fluid Systems
Two hydrogen generators based on reactions involving magnesium and steam have been proposed as means for generating the fuel (hydrogen gas) for such fuel-cell power systems as those...
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Briefs: Medical
A method of sensitive detection of bacterial spores within delays of no more than a few hours has been developed to provide an alternative to a prior three-day NASA standard culture-based assay. A...
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Briefs: Medical
A method of rapid detection of bacterial spores is based on the discovery that a heat shock consisting of exposure to a temperature of 100 °C for 10 minutes causes the complete...
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Briefs: Photonics/Optics
An established method of room-temperature interferometric null testing of mirrors having simple shapes (e.g., flat, spherical, or spheroidal) has been augmented to enable measurement of...
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Briefs: Physical Sciences
Microleaks for inlets of mass spectrometers used to analyze atmospheric gases can be fabricated in silicon wafers by means of photolithography, etching, and other techniques that are commonly...
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Briefs: Physical Sciences
Series-coupled pairs of whispering-gallery-mode optical microresonators have been demonstrated as prototypes of stable, narrow-band-pass photonic filters. Characteristics that are generally...
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Briefs: Information Technology
An improved method of model-based diagnosis of a complex engineering system is embodied in an algorithm that involves considerably less computation than do prior such algorithms. This...
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Briefs: Information Technology
A computationally efficient method has been developed to enable optimization of the placement of sensors for the purpose of diagnosis of a complex engineering system (e.g., an aircraft or...
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Briefs: Information Technology
Truncation Depth Rule-of-Thumb for Convolutional Codes
In this innovation, it is shown that a commonly used rule of thumb (that the truncation depth of a convolutional code should be five times the memory length, m, of the code) is accurate only for rate 1/2 codes. In fact, the truncation depth should be 2.5 m/(1 – r), where r is the code rate....
Briefs: Photonics/Optics
A proposed metrology system would be incorporated into a proposed telescope that would include focusing optics on a rigid bench connected via a deployable mast to another rigid bench...
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Briefs: Photonics/Optics
Formation Flying of Components of a Large Space Telescope
A conceptual space telescope having an aperture tens of meters wide and a focal length of hundreds of meters would be implemented as a group of six separate optical modules flying in formation: a primary-membrane-mirror module, a relay-mirror module, a focal-plane-assembly module containing...
Briefs: Photonics/Optics
Laser Metrology Heterodyne Phase-Locked Loop
A method reduces sensitivity to noise in a signal from a laser heterodyne interferometer. The phase-locked loop (PLL) removes glitches that occur in a zero-crossing detector's output [that can happen if the signal-to-noise ratio (SNR) of the heterodyne signal is low] by the use of an internal oscillator...
Briefs: Photonics/Optics
Crystalline whispering gallery mode resonators (CWGMRs) made of crystals with axial symmetry have ordinary and extraordinary families of optical modes. These modes have substantially...
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Briefs: Electronics & Computers
Spatial Modulation Improves Performance in CTIS
Suitably formulated spatial modulation of a scene imaged by a computed-tomography imaging spectrometer (CTIS) has been found to be useful as a means of improving the imaging performance of the CTIS. As used here, “spatial modulation” signifies the imposition of additional, artificial structure on...
Application Briefs: Motion Control
Just a few years ago, the use of computational fluid dynamics (CFD) in most aerospace companies was restricted to pure research or troubleshooting problems with existing designs. But in the past...
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Briefs: Green Design & Manufacturing
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Articles: Robotics, Automation & Control
When it comes to choosing a flowmetering device, some users assume “one size fits all.” In reality, there are significant differences between flowmeter types, and each design has its unique “pros and cons.”...
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Briefs: Electronics & Computers
Oxide Fiber Cathode Materials for Rechargeable Lithium Cells
LiCoO2 and LiNiO2 fibers have been investigated as alternatives to LiCoO2 and LiNiO2 powders used as lithium-intercalation compounds in cathodes of rechargeable lithium-ion electrochemical cells. In making such a cathode, LiCoO2 or LiNiO2 powder is mixed with a binder [e.g.,...
Articles: Motion Control
For over a hundred years, machine parts composed of mechanical carbon have provided an alternative solution in applications where temperature and atmosphere conditions prevent the use of...
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Briefs: Energy
Electromagnetically Clean Solar Arrays
The term “electromagnetically clean solar array” (EMCSA) refers to a panel that contains a planar array of solar photovoltaic cells. The cells are laminated with shielding, narrow-current-loop wiring, and structural supports. EMCSAs could be useful in applications that require limited electromagnetic interference.
Application Briefs: Aerospace
Just a few years ago, the use of computational fluid dynamics (CFD) in most aerospace companies was restricted to pure research or troubleshooting problems with existing designs. But in the past...
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