Briefs: Photonics/Optics

A proposed optoelectronic system based on imaging-lidar and differential-altimetry techniques would generate data equivalent to a height map of a surface area. Originally conceived for use in...

Briefs: Electronics & Computers

Complementary metal oxide/semiconductor (CMOS) image sensors would be capable of operation in a time-delayed-integration (TDI) mode. Heretofore, the only semiconductor electronic image...

Briefs: Physical Sciences

A proposed method of compressing image data would exploit the well-known capability of a converging lens to generate the Fourier transform of an image by purely optical means, in much...

Briefs: Physical Sciences

In an alternative to the optical image-compression method of the preceding article, the Fourier transform of the input image would be formed on the output plane by white-light holography,...

Briefs: Information Technology

Algorithms have been developed to enable a robotic vision system to recognize, in real time (at a rate between 0.5 and 2 frames per second), known objects lying on the ground. In...

Briefs: Information Technology

DVQ (which stands for "digital video quality") is a metric for evaluating the visual quality of digitized video images. Other video-quality metrics have been proposed, but it appears that each of...

Briefs: Software
Infrastructure Software for Mining Image Data Bases

Diamond Eye is a computer program that enables a user equipped with only a personal computer, web-browser software, and a network connection to analyze large collections of scientific image data. The system is based on a distributed applet/server architecture that provides platform-independent...

Briefs: Software
Software for Rapid Processing and Display of Earth Data

Digital Earth Workbench is a computer program that facilitates retrieval of Earth-related imagery and viewing of the imagery on either an ordinary computer video screen or a virtual-reality (head-tracked stereoscopic) display system. Examples of imagery that can be processed by

this...

Briefs: Electronics & Computers

A novel micromachined incandescent light source has been designed and fabricated to operate at temperatures exceeding 2,500 K. The high-temperature, tungsten filament-based source has a high-brightness,...

Briefs: Electronics & Computers
Automatic Bias Compensation in GPS Receivers

A technique of automatic bias compensation has been devised to correct errors caused by variations among electronic components in Global Positioning System (GPS) receivers that use the coarse/acquisition (C/A) GPS code. Even though there are large government and commercial markets for such GPS...

Briefs: Electronics & Computers

Theoretical calculations verified by experiments have shown that suitably designed ribbons made of alumina can serve as low-loss dielectric waveguides for electromagnetic radiation at...

Briefs: Software
Multithreading Program for Retrieval of Optical Phase Fields

A multithreading computer program performs phase-retrieval and -unwrapping calculations to extract accurate image phase maps from noisy image magnitude fields generated by adaptive optics. [As used here, "phase retrieval" signifies the calculation of phase map modulo 2µ, while...

Briefs: Software
Software for Analyzing Earth/Spacecraft Radio Interference

The Spectral Analysis Tool (SAT) computer program assists in analysis of interference between radio signals in Earth/spacecraft communications. SAT provides an easy-to-use interactive graphical interface with a menu for selecting among the following utility subprograms: an editor for...

Briefs: Materials

"Smart coatings" denotes a class of high-temperature-resistant, multilayer, thin (total thickness < 10 µm) films that contain predominantly planar layers of sensor circuitry...

Briefs: Materials
Aggregate-Search Approach for Planning and Scheduling

Several algorithms developed for use in automated planning and scheduling of sets of interdependent activities employ aggregation techniques to increase the efficiency of searching for temporal assignments that are legal in the sense that they do not violate constraints. In the...

Briefs: Materials

Some success has been achieved in a development program directed toward improving the mechanical properties of electroformed copper-alloy structural components. Typical of such components are...

Briefs: Mechanical & Fluid Systems

Experiments have shown that an assembly of multiple free-piston Stirling engines can be designed and constructed in such a way as to both (1) make the vibrations of the engines...

Briefs: Mechanical & Fluid Systems

An important secondary topic addressed in the research and development effort described in the preceding article is the use of artificial neural networks to improve the monitoring...

Briefs: Mechanical & Fluid Systems

A special-purpose grinding tool and fixtures have been developed for reworking an edge of a seal surface on a nozzle-throat-support housing in a rocket engine (see Figure 1) to...

Briefs: Information Technology

Cascade error projection (CEP) is an improved learning algorithm for artificial neural networks. CEP is reliable and suitable for efficient implementation in very-large-scale integrated...

Briefs: Information Technology

The Thermal Expert System (TEXSYS) computer program exerts real-time control over a complicated thermal-regulatory system that includes evaporators, condensers, a pump, valves, and sensors....

Briefs: Physical Sciences

Biomorphic gliders are small robotic microflyers proposed for use in scientific exploration of planetary atmospheres and terrains that capture some key features of insect and bird flight. Biomorphic gliders as biomorphic...

Briefs: Physical Sciences

A process and a laboratory setup to implement the process (see figure) have been devised to enable the acquisition of time-resolved data on the thermal decomposition of a specimen of...

Briefs: Physical Sciences

Laser thermogravimetric analysis (laser TGA) is a technique that yields time-resolved data on the thermal decomposition of a specimen of a solid material exposed to a heat flux comparable to the...

Briefs: Mechanical & Fluid Systems
Stable Microwave-Beam-Riding Spacecraft

The work considers passive dynamic stability of sail craft, propelled by microwave beams. Such systems are under consideration as low-cost means of interstellar travel. Sail-craft shapes offering passive dynamic (neutral) stability are identified. Passive stability is a key mission-enabling attribute. Very...

Briefs: Physical Sciences
Ultralight Balloon Systems for Exploring Uranus and Neptune

A report proposes ultralight balloon systems to carry a 10-kg payload, including scientific instruments for exploring the atmospheres of Uranus and Neptune. The system masses to be transported to those planets would be kept low by not transporting balloon-inflating gases. Each...

Briefs: Materials
Foaming in Place for Outer-Space Applications

A report discusses the adaptation of foaming-in-place techniques and materials to outer-space applications. Foaming in place is used commercially in terrestrial sealing, insulating, bonding, and retrofitting applications. The room-temperature outer-space versions of foaming in place are...

Briefs: Photonics/Optics

A new design for a complementary metal oxide/semiconductor (CMOS) snapshot imaging device of the photodiode-based, active-pixel-sensor (APS) type calls for features to prevent...

Briefs: Motion Control
Advanced, Lightweight, Low-Power-Consumption Actuator Brake

An advanced, lightweight, low-power consumption brake has been developed to satisfy NASA's special requirements for use on actuators during spaceflight. This brake can increase the stopping, holding, and parking ability of a spacecraft while reducing its electrical power consumption....

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