Briefs: Software
RBK4 is a computer program for testing electronic components for susceptibility to single-event upsets (SEUs). RBK4 controls the computer on which it is executed to communicate with both the board holding the device under test (DUT), a power supply, and other laboratory instruments including custom...
Briefs: Physical Sciences
The Automated Adaptive Signal Processing (AASP) computer program extracts wind data from the outputs of Doppler-radar wind profilers (DRWPs). Unlike prior software used for this purpose, AASP does not rely on manual intervention to prevent a DRWP system from locking onto and tracking...
Briefs: Materials
Blends of refrigerant fluids have been developed as improved alternatives to conventional chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) refrigerants, which contribute to depletion of stratosphere ozone. Each blend of this type is a zeotropic or nearly azeotropic mixture of...
Briefs: Materials
The proposed rocket engine includes a combustion chamber actively cooled by liquid oxygen: Heat from the combustion chamber vaporizes the flowing liquid oxygen, and the absorption of latent heat of vaporization contributes to cooling of the combustion-chamber wall. The resulting high-vapor-quality (mostly vapor)...
Briefs: Materials
Ti3SiC2 has been proposed as a mate- rial for ohmic contacts on SiC-based electronic and microelectromechanical devices intended to operate at temperatures >600 °C and/or in corrosive environments. Although SiC is stable and devices made of SiC are capable of functioning at elevated...
Briefs: Mechanical & Fluid Systems
Improved designs have been conceived for lightweight tubes that can withstand the large (as much as 8 or 9 volume percent) freeze/thaw expansions and contractions of typical heat-transfer fluids like water and ammonia. Intended originally for radiators for rejecting waste heat from spacecraft, these...
Briefs: Mechanical & Fluid Systems
Simple mechanisms have been devised to facilitate the blowdown of large diesel engines. As explained below, these mechanisms reduce the amount of time and effort that must be expended to...
Briefs: Mechanical & Fluid Systems
Structural dynamics are often an important consideration when evaluating system characteristics. A concern related to structural dynamics is the analysis of flutter for a flight vehicle. The instability associated with flutter can be quite sensitive to the structural dynamics; therefore, analysis of...
Briefs: Information Technology
Compressed symbology is a product-identification method that was pioneered by NASA for tracking space-shuttle parts and is now being used to mark everything from groceries to automobile parts. Based on a system of two-dimensional marks applied to parts, compressed symbology was developed at NASA's...
Briefs: Physical Sciences
A report proposes a design concept for synthesizing a reflecting telescope with a large-aperture (diameter ≈100 m) primary mirror from a sparse arrangement of four smaller (diameter ≈10 m) primary mirrors. The telescope would be placed in orbit for viewing Earth with high resolution....
Briefs: Mechanical & Fluid Systems
Two reports summarize progress thus far in the continuing development of a spacecraft nuclear reactor, some or all of the fuel rods of which would not be loaded until the spacecraft was in orbit. (Keeping the fuel rods out of the reactor core before and during launch is intended to...
Briefs: Mechanical & Fluid Systems
A report proposes the development of two different mechanisms that would prevent inadvertent startup of reactors in nuclear-fission-based propulsion and power systems in future spacecraft. The purpose of this development is to contribute to safety by ensuring that radioactivity is kept to...
Briefs: Information Technology
A report discusses the potential application of artificial intelligence (AI) to planning, scheduling, and control of the optical configuration and other aspects of the operations of a large astronomical interferometer. Scientific demand and technical requirements necessitate...
Briefs: Electronics & Computers
A report proposes a method of cooperative modulation between (1) low-power radio transceivers associated with sensors geographically dispersed on a remote planet for relaying information between the sensors and an Earth station. The method, denoted node selection on orthogonal...
Briefs: Physical Sciences
A report proposes a method to increase the accuracy of Doppler measurements made at the beginnings and endings of Earth/spacecraft radio occultations. Such measurements can reveal structural details of occulting objects in outer space. Heretofore, one-way measurements have been...
Briefs: Materials
A brief report summarizes an investigation of less-toxic alternatives to toxic monopropellant fluids used in launch vehicles, upper stages, and spacecraft propulsion. The toxic fluids in question are (1) hydrazine and its derivatives, used, variously, as fuels or by themselves as...
Briefs: Electronics & Computers
A report describes an application-specific integrated circuit (ASIC) for controlling a power-switching metal oxide semiconductor field-effect transistor (MOSFET) in a spacecraft power-supply system. Denoted an SCA (for switch-control ASIC), this ASIC is designed to be radiation-hard and to...
Briefs: Mechanical & Fluid Systems
An improved technique of limited-precision arithmetic has been devised for use in convolutional filtering of image data prior to conversion of the data to binary form. Both...
Briefs: Electronics & Computers
The Meteorological Range Safety Support System/Eastern Range Dispersion Assessment System (MARSS/ERDAS) is a system of interconnected computer workstations designed to acquire, process, and disseminate nearly real-time meteorological data and outputs of mathematical models of the atmospheric...
Briefs: Software
The Reconstruction of Serial Sections (ROSS) computer program processes data from a series of tomograms to generate a three-dimensional (3D) representation of an object, and further processes data from the 3D representation to enable the viewing of any part of the object from any of an...
Briefs: Software
DARWIN is a computer program that provides access, via the Internet, to geographically dispersed NASA computer archives of both meta-data and raw test data from wind tunnels and raw simulation data from computational fluid dynamics (CFD) sites. DARWIN facilitates the manipulation and...
Briefs: Physical Sciences
A miniature, battery-powered, semiautonomous environmental monitoring instrument contains advanced meteorological sensors, a Global Positioning System (GPS) receiver for determining its position, radio-communication circuitry, and a controller that performs measurement, control, and data-communication...
Briefs: Electronics & Computers
An improved mathematical model enables the somewhat more accurate prediction of the spectral response of a mixer circuit (see figure) that comprises a twin-slot antenna coupled via coplanar...
Briefs: Electronics & Computers
An improved charge-termination technique has been developed to obtain a more accurate balance between charge and discharge of rechargeable lithium-ion-based electrochemical cells and batteries. The technique has been demonstrated experimentally and is now in use in a laboratory battery...
Briefs: Electronics & Computers
A suite of electronic test equipment has been developed for use in the measurement of key electrical characteristics of advanced, high-speed integrated circuits for communications,...
Briefs: Software
A software system has been developed for use in Earth operations centers communicating with a robotic exploratory vehicle (rover) on Mars. The software was designed for and field-tested on the Field Integrated Design and Operations rover — a prototype similar to rovers of the...
Briefs: Software
A computer program automatically generates topographical maps from data collected by scan-mode synthetic-aperture radar (scanSAR) during the Shuttle Radar Topography Mission (SRTM). A preprocessing subprogram subdivides the SAR data, along with ancillary spacecraft-motion, control,...
Briefs: Electronics & Computers
An algorithm that can discover potentially interesting objects in image data has been formulated and implemented in software. The algorithm is intended for applications in which the target objects are mathematically ill-defined and/or not known or specified in advance. Potential applications include...
Briefs: Electronics & Computers
An Automated Test Case Generator computer program generates parameter-based test cases for testing software and hardware systems. Given N parameters — each of which represents a kind of variation for testing — and a finite set of possible values for each parameter, the program generates individual...