Briefs: Physical Sciences

An improved method of making an electronic oscillator track the frequency of an atomic-clock resonance transition is based on fitting a theoretical nonlinear curve to measurements at...

Briefs: Physical Sciences

Leak detection and location remain a common problem in NASA and industry, where gas leaks can create hazardous conditions if not quickly detected and corrected. In order to...

Briefs: Physical Sciences
Submonolayer Quantum Dot Infrared Photodetector

A method has been developed for inserting submonolayer (SML) quantum dots (QDs) or SML QD stacks, instead of conventional Stranski-Krastanov (S-K) QDs, into the active region of intersubband photodetectors. A typical configuration would be InAs SML QDs embedded in thin layers of GaAs, surrounded by...

Briefs: Physical Sciences
Ionization-Assisted Getter Pumping for Ultra-Stable Trapped Ion Frequency Standards

A method eliminates (or recovers from) residual methane buildup in getter-pumped atomic frequency standard systems by applying ionizing assistance. Ultra-high stability trapped ion frequency standards for applications requiring very high reliability, and/or low...

Briefs: Physical Sciences
Phase-Array Approach to Optical Whispering Gallery Modulators

This technology leverages the well-defined orbital number of a whispering gallery modulator (WGM) to expand the range of applications for such resonators. This property rigidly connects the phase variation of the field in this mode with the azimuthal angle between the coupling...

Briefs: Physical Sciences
Fiber-Optic Continuous Liquid Sensor for Cryogenic Propellant Gauging

An innovative fiber-optic sensor has been developed for low-thrust-level settled mass gauging with measurement uncertainty

Briefs: Physical Sciences
Measurement of the Length of an Optical Trap

NASA Glenn has been involved in developing optical trapping and optical micromanipulation techniques in order to develop a tool that can be used to probe, characterize, and assemble nano and microscale materials to create microscale sensors for harsh flight environments. In order to be able to...

Briefs: Physical Sciences
Mode Tracker for Mode-Hop-Free Operation of a Laser

A mode-tracking system that includes a mode-controlling subsystem has been incorporated into an external-cavity (EC) quantum cascade laser that operates in a mid-infrared wavelength range. The mode-tracking system makes it possible to perform mode-hop-free wavelength scans, as needed for...

Briefs: Information Technology
Physical Invariants of Intelligence

A program of research is dedicated to development of a mathematical formalism that could provide, among other things, means by which living systems could be distinguished from non-living ones. A major issue that arises in this research is the following question: What invariants of mathematical models of the...

Briefs: Information Technology
Rocket-Plume Spectroscopy Simulation for Hydrocarbon-Fueled Rocket Engines

The UV-Vis spectroscopic system for plume diagnostics monitors rocket engine health by using several analytical tools developed at Stennis Space Center (SSC), including the rocket plume spectroscopy simulation code (RPSSC), to identify and quantify the alloys from the...

Briefs: Information Technology
Research on Spoken Dialogue Systems

Research in the field of spoken dialogue systems has been performed with the goal of making such systems more robust and easier to use in demanding situations. The term “spoken dialogue systems” signifies unified software systems containing speech-recognition, speech-synthesis, dialogue management, and...

Briefs: Information Technology
Injecting Errors for Testing Built-in Test Software

Two algorithms have been conceived to enable automated, thorough testing of Built-in test (BIT) software. The first algorithm applies to BIT routines that define pass/fail criteria based on values of data read from such hardware devices as memories, input ports, or registers. This algorithm...

Briefs: Information Technology
Guidance and Control System for a Satellite Constellation

A distributed guidance and control algorithm was developed for a constellation of satellites. The system repositions satellites as required, regulates satellites to desired orbits, and prevents collisions.

Briefs: Mechanical & Fluid Systems
Dedicated Deployable Aerobraking Structure

A dedicated deployable aerobraking structure concept was developed that significantly increases the effective area of a spacecraft during aerobraking by up to a factor of 5 or more (depending on spacecraft size) without substantially increasing total spacecraft mass. Increasing the effective aerobraking...

Briefs: Electronics & Computers
Portable Health Algorithms Test System

A document discusses the Portable Health Algorithms Test (PHALT) System, which has been designed as a means for evolving the maturity and credibility of algorithms developed to assess the health of aerospace systems. Comprising an integrated hardware-software environment, the PHALT system allows systems...

Briefs: Electronics & Computers
Technique for Performing Dielectric Property Measurements at Microwave Frequencies

A paper discusses the need to perform accurate dielectric property measurements on larger sized samples, particularly liquids at microwave frequencies. These types of measurements cannot be obtained using conventional cavity perturbation methods, particularly for...

Briefs: Mechanical & Fluid Systems

Progress has been made in the development of a family of robotic land vehicles having modular and minimalist design features chosen to impart a combination of robustness, reliability, and...

Briefs: Robotics, Automation & Control
Compact, Lightweight Servo-Controllable Brakes

Compact, lightweight servo-controllable brakes capable of high torques are being developed for incorporation into robot joints. A brake of this type is based partly on the capstan effect of tension elements, which is described by the well known equation

Briefs: Mechanical & Fluid Systems
Robotic Arm Manipulator Using Active Control for Sample Acquisition and Transfer, and Passive Mode for Surface Compliance

A robotic arm that consists of three joints with four degrees of freedom (DOF) has been developed. It can carry an end-effector to acquire and transfer samples by using active control and comply with surface topology in a...

Articles: Energy

In just the last few years, innovation in alternative-energy technologies have gained significant footholds in product development lifecycles and are rapidly changing our individual...

News: Energy

Researchers at the University of Leeds have found an energy-efficient way to make hydrogen out of used vegetable oils discarded by restaurants and other establishments. The process generates some of...

News: Green Design & Manufacturing

Researchers at the University of Maryland are developing a new "thermally elastic" metal alloy for use in advanced refrigeration and air conditioning systems. The technology...

Articles: Green Design & Manufacturing
Optimized Power Devices Enable Energy Efficient Solar Inverters and Micro-Converters

As the demand for greener appliances and consumer products soars across the globe, and energy savings becomes a global phenomenon (and necessity) in residential and commercial environments, solar and wind power technologies have begun to proliferate in cities...

Question of the Week
Should brain scans be admissible as legal evidence?

This week's question concerns brain scans and the legal system. In 2008 a judge in India convicted a woman of murdering her fiancee based partly on brain scan evidence that gauged her ability to remember details of the crime. And in the US, fMRI scans have already found their way into...

News: Energy

The latest e-zine from Green Design & Manufacturing is here! The premiere issue of Solar and Wind Power features articles, tech briefs, application stories, and more regarding alternative energy...

Videos: Energy

A new solar concentrator from Ph.D. student Jason Karp of the University of California, San Diego collects sunlight with thousands of small lenses imprinted on a common sheet. All these lenses couple...

Briefs: Energy
Most wind farms consist of horizontal axis wind turbines (HAWTs), but an alternative paradigm for wind energy extraction is found in vertical axis wind turbine (VAWT) designs. A single spatially-isolated VAWT has a significantly lower power coefficient.
Briefs: Energy
In recent years, better stabilizer formulations for ethylene vinyl-acetate have been developed, giving more confidence in the long-term stability of PV packaging materials. Because of this, some manufacturers have stopped using Ce-doped glass. National Renewable Energy Laboratory researchers studied Ce-free glass.
Question of the Week
Was the discovery of Russian spies still operating in the US surprising?

This week's question concerns the recent discovery of Russian spies still operating in the US. In June, authorities uncovered a Russian spy ring of 10 individuals operating in New York and Cambridge. Last week, the US and Russian governments completed a "spy swap" in...

Videos