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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Computer program, SPAN-C, measures the dry heat thermal sterilization process applied to a planetary capsule and calculates the time required for heat application, steady state conditions, and cooling. The program is based on the logarithmic survival of micro-organisms. Temperature profiles must be input on cards.
Computer program, SPAN, measures the dry heat thermal sterilization process applied to a planetary capsule and calculates the time required for heat application, steady state conditions, and cooling. The program is based on the logarithmic survival of micro-organisms. Temperature profiles must be input on tape.
Space flight offers the opportunity to study linear bioaccelerometers (vestibular maculas) in the virtual absence of a primary stimulus, gravitational acceleration. Macular research in space is particularly important to NASA because the bioaccelerometers are proving to be weighted neural networks in which information is distributed for parallel processing. Neural networks are plastic and highly adaptive to new environments. Combined morphological-physiological studies of maculas fixed in space and following flight should reveal macular adaptive responses to microgravity, and their time-course. Ground-based research, already begun, using computer-assisted, 3-dimensional reconstruction of macular terminal fields will lead to development of computer models of functioning maculas. This research should continue in conjunction with physiological studies, including work with multichannel electrodes. The results of such a combined effort could usher in a new era in understanding vestibular function on Earth and in space. They can also provide a rational basis for counter-measures to space motion sickness, which may prove troublesome as space voyager encounter new gravitational fields on planets, or must re-adapt to 1 g upon return to earth.
A mid-fidelity computational fluid dynamics tool called RotCFD - specifically developed to aid in rotorcraft conceptual design efforts - has been applied to the study of rotor wake interactions of civil tiltrotor aircraft in the immediate vicinity of vertiport/airport ground infrastructure. This issue has grown in importance as previous NASA studies have suggested that civil tiltrotor aircraft can potentially have a significant impact on commercial transport aviation. Current NASA reference designs for such civil tiltrotor aircraft are focused on a size category of 90-120 passengers. Notional concepts of operations include simultaneous non-interfering flight into and out of congested airports having vertiports, that is, prepared VTOL takeoff and landing zones, or underutilized short runways for STOL operation. Such large gross-weight vehicles will be generating very high induced velocities. Inevitably, the interaction of the rotor wake with ground infrastructure such as terminals/jetways must be considered both from an operational as well as design perspective.
Terminal reentry and dynamics evaluation computer program for small particles, using point-mass calculation during initial phase and determining drag coefficient
Algorithm computes streamwise position of terminal aerodynamic shock in inlet of engine of supersonic airplane. Signal representative of position of shock must be available to propulsion-control system of airplane to ensure proper operation of inlet. Algorithm computes position of shock with resolution much finer than spacing between transducers and requires neither increase in number of transducers nor other changes in pressure-measuring equipment.
Control and performance monitoring of NASA's High Burst Rate Link Evaluation Terminal (HBR-LET) is accomplished by using several software control modules. Different software modules are responsible for controlling remote radio frequency (RF) instrumentation, supporting communication between a host and a remote computer, controlling the output power of the Link Evaluation Terminal and data display. Remote commanding of microwave RF instrumentation and the LET digital ground terminal allows computer control of various experiments, including bit error rate measurements. Computer communication allows system operators to transmit and receive from the Advanced Communications Technology Satellite (ACTS). Finally, the output power control software dynamically controls the uplink output power of the terminal to compensate for signal loss due to rain fade. Included is a discussion of each software module and its applications.
FEMoM3DR is a computer code written in FORTRAN 77 to compute radiation characteristics of antennas on 3D body using combined Finite Element Method (FEM)/Method of Moments (MoM) technique. The code is written to handle different feeding structures like coaxial line, rectangular waveguide, and circular waveguide. This code uses the tetrahedral elements, with vector edge basis functions for FEM and triangular elements with roof-top basis functions for MoM. By virtue of FEM, this code can handle any arbitrary shaped three dimensional bodies with inhomogeneous lossy materials; and due to MoM the computational domain can be terminated in any arbitrary shape. The User's Manual is written to make the user acquainted with the operation of the code. The user is assumed to be familiar with the FORTRAN 77 language and the operating environment of the computers on which the code is intended to run.
Compact test set integrated in computer-aided design system. Test set performs functional tests on very-large-scale integrated (VLSI) circuits. Makes tests from points within VLSI chip as well as at input and output pins. Used for quality control and design; in latter capacity, checks internal logic functions on chip and feed results directly to computer-aided design system for correction. Also simulates operation of chip design before chip is made. VLSI Tester contains three power supplies, control logic, and standard multibus circuit board in aluminum chassis. Chassis fits under platform of microprobe station. Multibus board links tester to interactive terminals and to host computer.
Progress on the Mesoscale and Severe Storms (MASS) data management and analysis system is described. An interactive atmospheric data base management software package to convert four types of data (Sounding, Single Level, Grid, Image) into standard random access formats is implemented and integrated with the MASS AVE80 Series general purpose plotting and graphics display data analysis software package. An interactive analysis and display graphics software package (AVE80) to analyze large volumes of conventional and satellite derived meteorological data is enhanced to provide imaging/color graphics display utilizing color video hardware integrated into the MASS computer system. Local and remote smart-terminal capability is provided by installing APPLE III computer systems within individual scientist offices and integrated with the MASS system, thus providing color video display, graphics, and characters display of the four data types.
Spaceflight offers the unique opportunity to study linear bioaccelerometers (vestibular maculas) in the virtual absence of a primary stimulus, gravitational acceleration. Combined morphological-physiological studies of maculas fixed in space and following flight should reveal macular adaptive responses to microgravity, and their time-course. Ground-based research, already begun, using computer-assisted, three-dimensional reconstructions of macular terminal fields will lead to development of computer models of functioning maculas. This research should continue in conjunction with physiological studies, including work with multichannel electrodes.
The paper considers the utility of having remote terminals on a Landsat image processing system and the development of efficient data transfer strategies such as data compression. The approach is to link an image processing terminal (located in a mobile van) to a multiuser host computer via the Communications Technology Satellite and a leased phone line. The host computer will share time between the remote state users and local users. The terminal includes a minicomputer, a color video display, and a communications interface, and the user has access to all of the resources of the host facility via the data link. While at present the terminal acts in the display-only mode, the computing capability of the terminal can be varied from display-only up to a stand-alone image processing system. An analysis of trade-offs between data link and remote terminal capacities is described with attention to the evaluation of the system by state users and the selection of a system architecture suitable to unique needs.
A joint NASA Dryden Flight Research Facility and Johnson Space Center program was conducted to determine the feasibility of the autonomous recovery of a spacecraft using a ram-air parafoil system for the final stages of entry from space that included a precision landing. The feasibility of this system was studied using a flight model of a spacecraft in the generic shape of a flattened biconic which weighed approximately 150 lb and was flown under a commercially available, ram-air parachute. Key elements of the vehicle included the Global Positioning System guidance for navigation, flight control computer, ultrasonic sensing for terminal altitude, electronic compass, and onboard data recording. A flight test program was used to develop and refine the vehicle. This vehicle completed an autonomous flight from an altitude of 10,000 ft and a lateral offset of 1.7 miles which resulted in a precision flare and landing into the wind at a predetermined location. At times, the autonomous flight was conducted in the presence of winds approximately equal to vehicle airspeed. Several techniques for computing the winds postflight were evaluated. Future program objectives are also presented.
A joint NASA Dryden Flight Research Facility and Johnson Space Center program was conducted to determine the feasibility of the autonomous recovery of a spacecraft using a ram-air parafoil system for the final stages of entry from space that included a precision landing. The feasibility of this system was studied using a flight model of a spacecraft in the generic shape of a flattened biconic that weighed approximately 150 lb and was flown under a commercially available, ram-air parachute. Key elements of the vehicle included the Global Positioning System guidance for navigation, flight control computer, ultrasonic sensing for terminal altitude, electronic compass, and onboard data recording. A flight test program was used to develop and refine the vehicle. This vehicle completed an autonomous flight from an altitude of 10,000 ft and a lateral offset of 1.7 miles that resulted in a precision flare and landing into the wind at a predetermined location. At times, the autonomous flight was conducted in the presence of winds approximately equal to vehicle airspeed. Several novel techniques for computing the winds postflight were evaluated. Future program objectives are also presented.
AMTRAN II on-line remote terminal for IBM 1620 computer to improve man-machine communication
Random-search algorithm employs local and global properties to solve two-point boundary value problem in Pontryagin maximum principle for either fixed or variable end-time problems. Mixed boundary value problem is transformed to an initial value problem. Mapping between initial and terminal values utilizes hybrid computer.
The author has identified the following significant results. Increase in radiance values is directly related to decrease in vegetative biomass, though not in a linear manner. Should the relationship hold true over an entire growing season, this would allow an extremely rapid evaluation of range condition. Computer access by remote terminal would allow production of this type of range condition evaluation in near real time, which is essential if grazing practice decisions are to be made based on satellite imagery acquisition. Negating the manipulation of photographic products appears to be the logical way to provide satellite imagery data to the user in near real time. There appears to be a direct linear relationship between radiance values of bands 4 and 5 and increase in total inorganic ions (6 ions) of lakes in the Sand hills region. Consistent ion concentration of lakes during the year could allow their radiance values to serve as a means of equating radiance values from image to image.
A combined thermochemical cycle analysis computer program was designed. Input to the combined program is the same as input to the thermochemical cycle analysis program except that the extent of the reactions need not be specified. The combined program is designed to be run interactively from a computer time-sharing terminal. This mode of operation allows correction or modification of the cycle to take place during cycle analysis. A group of 13 thermochemical cycles was used to test the combined program.