Time-division multiplexer Patent
Time division multiplexer with magnetic latching relays
Meyer, J. F.↗
SEARCH · Engineering Papers
Results for “J Division”
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
An experimental evaluation of head-up display formats
Three types of head-up display format are investigated. Type 1 is an unreferenced (conventional) flight director, type 2 is a ground referenced flight path display, and type 3 is a ground referenced director. Formats are generated by computer and presented by reflecting collimation against a simulated forward view in flight. Pilots, holding commercial licenses, fly approaches in the instrument flight mode and in a combined instrument and visual flight mode. The approaches are in wind shear with varied conditions of visibility, offset, and turbulence. The displays are equivalent in pure tracking but there is a slight advantage for the unreferenced director in poor conditions. Flight path displays are better for tracking in the combined flight mode, possibly because of poor director control laws and the division of attention between superimposed fields. Workloads is better for the type 2 displays. The flight path and referenced director displays are criticized for effects of symbol motion and field limiting. In the subjective judgment of pilots familiar with the director displays, they are rated clearly better than path displays, with a preference for the unreferenced director. There is a fair division of attention between superimposed fields.
Naish, J. M.↗
Apollo 17 photographic processing control document
The control parameters are defined which are to be used by the Photographic Technology Division for the processing of all films flown on Apollo Mission J-3. The procedures necessary for establishment of processing control are given along with information for denoting and solving any problem areas or conflicts which may occur prior to the mission.
Weinstein, M. S.↗
An application of pressure division for calibrating ionization gauges
Pressure-division system for vacuum ionization gauge calibration
PRESSURE APPARATUS↗
Model exospheres of the ringed planets
The theory of rotating ion exospheres in dipolar magnetic field geometries is used to predict certain effects of the rings on the inner plasmaspheres of the ringed planets Jupiter, Saturn, and Uranus. The analysis here assumes a purely ionospheric source. It is found that if rings affect only the trapped plasma, the cold plasma density at Saturn will be either reduced or increased by a factor of approximately 2 at L = 1.65, depending on whether the ring populates or empties the trapped trajectories. It is found that if all cold plasma particles on trapped orbits are absorbed and the rings are not a source of plasma, this simple exospheric theory can explain the ionospheric density profile inferred from the Pioneer 11 Saturn radio occultation experiment, in which a localized peak in the profile was observed on field lines threading the Guerin division between the C and D rings.
Luhmann, J. G.↗
Optical systems for digit-serial computation
High-accuracy optical systems for implementing digit-serial computations are discussed which incorporate parallelism and carry-free addition to achieve high processing speed. Employing on-line arithmetic, parallel calculations can be performed by the concurrent execution of operations. The algorithms are shown to be problem invariant and step invariant. Architectures using optical bistable devices and optical interconnects are discussed which can implement digit-serial addition, subtraction, multiplication, and division algorithms via the present approach.
Perlee, Caroline J.↗
An overview of MEMS-based micropropulsion development at JPL
Development of MEMS (Microelectromechanical Systems) micropropulsion at the Jet Propulsion Laboratory (JPL) is reviewed. This includes a vaporizing liquid micro-thruster for microspacecraft attitude control, a micro-ion emgine for microspacecraft primary propulsion or large spacecraft fine attitude control, as well as several valve studies, including a solenoid valve studied in collaboration with Moog Space Products Division, and a piezoelectric micro-valve.
MEMS micropropulsion↗
A Head Start to a Healthy Heart
Cambridge Heart, Inc., has licensed the only U.S. Food and Drug Administration-cleared tool to identify those at risk for sudden cardiac death (SCD). The Microvolt T-Wave Alternans Test(TM) was invented by Dr. Richard J. Cohen, a professor at the Harvard-Massachusetts Institute of Technology (MIT) Division of Health Sciences and Technology, with developmental support and funding from NASA's Johnson Space Center and the National Space Biomedical Research Institute (NSBRI) in Houston, Texas. In 1993, MIT licensed the technology to Cambridge Heart, Inc., a start-up company that Dr. Cohen helped to establish. Cambridge Heart's non-invasive technology measures T-wave alternans, a change from one heartbeat to the next that is too minute to be detected by a standard electrocardiogram. Cardiac patients with such a change in heartbeat regulation are faced with a much greater risk of ventricular arrhythmia and SCD than those without it. The company's ability to measure electrical alternans on a microvolt level has been clinically proven to be just as accurate as - and in some studies, more accurate than - more costly and somewhat risky, invasive procedures, such as electrophysiological testing.
Source record↗
Improving engineering system design by formal decomposition, sensitivity analysis, and optimization
A method for use in the design of a complex engineering system by decomposing the problem into a set of smaller subproblems is presented. Coupling of the subproblems is preserved by means of the sensitivity derivatives of the subproblem solution to the inputs received from the system. The method allows for the division of work among many people and computers.
Sobieski, J.↗
Baseband Processor for Communication Satellites
Baseband processing (BBP) system for advanced satellite communications successfully demonstrated. Provides increased data capacity through frequency-reusing multibeam antenna systems, using time-division multiple access (TDMA) and onboard satellite switching. Large numbers of thin-route trunking stations and user-based Earth terminals handled efficiently by satellite baseband switching. With BBP system, satellite routes data messages individually among locations anywhere in continental United States. Processes, controls, and routes message traffic among users. Time-division multiple access and baseband switching used.
Jirberg, Russell J.↗
Sensor network communications using space-division optical retro-reflectors for in-situ science applications
In this paper we present a peer-to-peer sensor network architecture using space-division optical retro-reflector to provide energy efficient communication services for in-situ science applications.
modulating retro-reflector in-situ science sensor ↗
Outer atmospheres of cool stars. I - The sharp division into solar-type and non-solar-type stars
Explore the source record for details and available documents.
Linsky, J. L.↗
Manned operations in the NASA MSC low- pressure chambers.
Man-rating of low-pressure chambers at Crew Systems Division and Structures and Mechanics Division of NASA Manned Spacecraft Center /MSC/ at Houston
LOW PRESSURE CHAMBER↗
High-speed wide band 20 x 20 microwave switch matrix
The use of a dynamic switching matrix for future communication satellites will significantly increase the communication channel capacity and improve the system capability and flexibility. This paper describes the design and development of a unique coupler crossbar 20 x 20 microwave switch matrix. This paper also presents the test results of the proof-of-concept model that meets the requirements for a high-speed satellite switched, time division multiple access (SS-TDMA) system.
Coban, E.↗
Marrying Social Media Approaches and Space Flight Control - Eight Years at SpaceOps
This paper shows how Marshall Space Flight Center's (MSFC) ISS Payload Operations Integration Center (POIC) is realizing the above goals via a) enhancements to the Console Log Tool (CoLT) first deployed in 2012 and b) the Communications Dashboard (CommDash) software suite deployed in 2017. In addition to technical discussion, the paper chronicles CommDash's role in emergence of an Agile development process and a Human Factors community of practice within MSFC's Payload Mission Operations Division (PMOD).
Scott, D. W.↗
Large Area Crop Inventory Experiment (LACIE). Bibliographic addenda, technical reports, papers, and memorandums published under supporting research and technology and other research, test, and evaluation contracts for the Earth observations division
There are no author-identified significant results in this report.
Aumann, J. B.↗
Carbon Monoxide Sensor
The fuel cell is a system which employs an electrochemical process to convert gases- J such as hydrogen and oxygen directly into electricity. Under NASA sponsorship, GE's Aircraft Equipment Division developed fuel cells to supply electrical power for the Gemini and Biosatellite spacecraft of the sixties and is currently working on advanced fuel cell development. This long-term effort has resulted in a series of spinoff applications using the same general technology for a variety of purposes, among them the recently marketed Dosimeter. The Dosimeter is designed to help users meet safety requirements for industrial atmospheres, as specified by the Occupational Safety and Health Administration and other regulatory agencies. The compact, pocket-sized sensor measures personnel exposure to carbon monoxide and provides both a visual and an audible alarm if the concentration of the gas exceeds present levels. The Dosimeter offers substantial improvement in measuring accuracy over earlier warning indicators.
Source record↗
The national land use data program of the US Geological Survey
The Land Use Data and Analysis (LUDA) Program which provides a systematic and comprehensive collection and analysis of land use and land cover data on a nationwide basis is described. Maps are compiled at about 1:125,000 scale showing present land use/cover at Level II of a land use/cover classification system developed by the U.S. Geological Survey in conjunction with other Federal and state agencies and other users. For each of the land use/cover maps produced at 1:125,000 scale, overlays are also compiled showing Federal land ownership, river basins and subbasins, counties, and census county subdivisions. The program utilizes the advanced technology of the Special Mapping Center of the U.S. Geological Survey, high altitude NASA photographs, aerial photographs acquired for the USGS Topographic Division's mapping program, and LANDSAT data in complementary ways.
Anderson, J. R.↗