A discrete-event simulation model, and a computer program that implements the model, have been developed as means of analyzing a spiral software-development process. This model can be tailored to specific development environments for use by software project managers in making quantitative...

By studying the Orbital Express mission, modeling the spacecraft and scenarios, and testing the system, a technique has been developed that uses recursive decomposition to represent procedural actions declaratively, schemalevel uncertainty reasoning to make uncertainty reasoning tractable, and lightweight, natural...

An algorithm that includes a collection of several subalgorithms has been devised as a means of synthesizing still other algorithms (which could include computer code) that utilize hashing to determine whether an element (typically, a number or other datum) is a member of a set (typically, a...

In contemporary spectrometers the wavelength selection is obtained through a dispersing optical element and a linear detector. The introduction of micro-cantilevers with fast response time, used as micro-shutters, allows the possibility to adopt a single sensing detector.

A scaleable technique based on ink-jet technology fabricates polymer microparticles with best-in-class size distribution. It is suitable for a variety of particle morphologies such as solid, porous, and microcapsules filled with gases, liquids, or a combination. Drugs or...

No protocol exists to determine whether life found on other planets or in space is indigenous to its locale, or is the result of contamination from probes sent by Earth. NASA seeks such a protocol in anticipation of manned exploration of Mars. The protocol is...

A company seeks a weight-saving alternative to sheets and wires of copper and aluminum that can operate at specific frequencies. The company wants to replace conductive casings, conductors, wires, grounding plates, and similar electronics structures with other...

Dr. Robert Braun began his NASA career at Langley Research Center in Virginia in 1987 after receiving a B.S in Aerospace Engineering from Penn State University. While at Langley, he worked on a number of advanced space systems concept and flight programs including the Mars Pathfinder, Mars Microbe, and Mars Surveyor 2001...

This week's question concerns the world-renowned Australian scientist Professor Frank Fenner - who helped to wipe out smallpox - and his prediction that humans will probably be extinct within 100 years. His reasoning includes overpopulation, environmental destruction, and climate change. Fenner stated that homo...

This week's question concerns our online "personas". While social networking sites such as Twitter and Facebook encourage members to use their real identities, a recent study on the usage habits on these sites has shown there's little correlation between how people act on...

This week’s question concerns the EPA’s regulation of greenhouse gas emissions. Last Thursday, the US Senate failed to pass legislation that would have prevented the Environmental Protection Agency (EPA) from regulating CO2 emissions from large factories, electric power companies, and automobiles. What do...

This week's question concerns a recent news item about how a Utah woman injured by a motorist while following a Google Maps route has filed a lawsuit claiming Google supplied unsafe directions (the motorist is also named in the lawsuit). The woman used her phone to download...