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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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At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS1966

Traversing probe Patent

Flow meter for measuring stagnation pressure in boundary layer around high speed flight vehicle

Degeer, M. D.↗
NASA NTRS1972

Long range laser traversing system

A study was carried out to determine the feasibility of a man-portable receiver system for land survey, which would be capable of detecting the optical scatter due to molecular and aerosol constituents of the atmosphere from a vertical laser beam. Tests were run with a beacon and receiver separated by approximately one mile. The system was consistently able to detect the laser signal regardless of background conditions.

Caudill, L. O.↗
NASA NTRS1974

Long range laser traversing system

The relative azimuth bearing between first and second spaced terrestrial points which may be obscured from each other by intervening terrain is measured by placing at one of the points a laser source for projecting a collimated beam upwardly in the vertical plane. The collimated laser beam is detected at the second point by positioning the optical axis of a receiving instrument for the laser beam in such a manner that the beam intercepts the optical axis. In response to the optical axis intercepting the beam, the beam is deflected into two different ray paths by a beam splitter having an apex located on the optical axis. The energy in the ray paths is detected by separate photoresponsive elements that drive logic networks for proving indications of: (1) the optical axis intercepting the beam; (2) the beam being on the left of the optical axis and (3) the beam being on the right side of the optical axis.

Caudill, L. O.↗
NASA NTRS1975

Energy loss of relativistic electrons and positrons traversing cosmic matter

Questions of adiabatic expansion are considered along with aspects of Compton scattering, bremsstrahlung, electronic excitation, synchrotron radiation, and electron-positron pair production. It is found that, unless the intergalactic magnetic field is very small, synchrotron radiation will dominate all other energy loss processes at ultrahigh electron and positron energies. The dependence of the loss rates on the cosmic epoch is also discussed.

Gould, R. J.↗
NASA NTRS1976

Absorption cell - A modified multiple-traversal device

A modified White-type multiple-transversal absorption cell used with a 5-m Littrow spectrometer is described. It can be introduced at a focus of the radiation beam without altering the beam configuration. The conventional White cell consists of three mirrors of equal focal length, with a distance of two focal lengths separating one of the mirrors from a mirror pair. The modification in the design consists of the addition of two mirrors at a slant placed behind the solitary mirror of the conventional configuration. The mirror arrangement reproduces the configuration of the exit beam for any number of transversals of the cell.

Jennings, D. E.↗
NASA NTRS1979

Possible traversals of Jupiter's distant magnetic tail by Voyager and by Saturn

In the present paper, it is shown that in the spring and summer of 1981, both Voyager-2 and Saturn will cross the expected region of the tail or wake about 7000 to 8000 Jupiter radii downstream of Jupiter. Should Jupiter's tail be well defined at this distance, Saturn's magnetopause may vary significantly as Saturn moves across the tail.

Scarf, F. L.↗
NASA NTRS1983

Ionospheric plasma bubble encounters or F region bottomside traversals?

Data from in situ Atmospheric Explorer (AE) measurements and ground-based ionosonde measurements of the ion composition and concentration in the equatorial plasma bubbles are analyzed. The ionosonde produced data on the bottomside electron density (NE) profiles and aided in ascertaining the satellite measurements as being in the topside or bottomside of the F layer. The AE data were taken during low latitude evening conditions at various altitudes, and revealed ion compositions consistent with plasma bubbles originating at the altitude of the steep F region bottomside ionization gradient. The lifetimes of NO ions were observed to be short even if the ions were dominant in the regions where the bubbles form. Vertical distortions of tens of kilometers in the equatorial F region occurred in the unstable postsunset period to the extent that the bubble formation area and the bottomside plasma region became virtually indistinguishable.

Benson, R. F.↗
NASA NTRS1988

Fine-scale traverses in cumulate rocks, Stillwater Complex: A lunar analogue study

The objective was to document finite-scale compositional variations in cumulate rocks from the Stillwater Complex in Montana and to interpret these data in the context of planetary magma fractionation processes such as those operative during the formation of the Earth's Moon. This research problem involved collecting samples in the Stillwater Complex and analyzing them by electron microprobe, X-ray fluorescence (XRF), and instrumental neutron activation analysis (INAA). The electron microprobe is used to determine the compositions of cumulus and intercumulus phases in the rocks, the XRF is used to determine the bulk-rock major element and trace element (Y, Sr, Rb, Zr, Ni, and Cr) abundances, and the INAA lab. is used to determine the trace element (Sc, Co, Cr, Ni, Ta, Hf, U, Th, and the REE) abundances of mineral separates and bulk rocks.

Elthon, Donald↗
NASA NTRS1992

Manifold traversing as a model for learning control of autonomous robots

This paper describes a recipe for the construction of control systems that support complex machines such as multi-limbed/multi-fingered robots. The robot has to execute a task under varying environmental conditions and it has to react reasonably when previously unknown conditions are encountered. Its behavior should be learned and/or trained as opposed to being programmed. The paper describes one possible method for organizing the data that the robot has learned by various means. This framework can accept useful operator input even if it does not fully specify what to do, and can combine knowledge from autonomous, operator assisted and programmed experiences.

Szakaly, Zoltan F.↗
NASA NTRS1998

South-North and radial traverses through the interplanetary dust cloud

Identical in situ dust detectors are flown on board the Galileo and Ulysses spacecraft. They record impacts of micrometeoroids in the ecliptic plane at heliocentric distances from 0.7 to 5.4 AU and in a plane almost perpendicular to the ecliptic from -79 deg to +79 deg ecliptic latitude. The combination of both Ulysses and Galileo measurements yield information about the radial and latitudinal distributions of micron and sub-micron sized dust in the solar system. Two types of dust particles were found to dominate the dust flux in interplanetary space: (1) Interplanetary micrometeoroids covering a wide mass range from 10(exp -16) to 10(exp -6) gr are mostly recorded inside 3 AU, and at latitudes below 30 deg; and (2) Interstellar grains with masses between 10(exp -14) and 10(exp -12) gr have been positively identified outside 3 AU near the ecliptic plane and outside 1.8 AU at high ecliptic latitudes (> 50 deg). Interstellar grains move on hyperbolic trajectories through the planetary system and constitute the dominant dust flux (1.5 x 10(exp -4)/ sq m sec) in the outer solar system and at high ecliptic latitudes. In order to compare and analyze the Galileo and Ulysses data sets, a new model is developed based on Divine's (1993) "Five populations of interplanetary meteoroids" model. By using this model, which takes into account the measured velocities and the effect of radiation pressure on small particles, we define four populations of meteoroids on elliptical orbits plus one population on hyperbolic orbits that all can fit the micrometeoroid flux observed by Galileo and Ulysses.

Gruen, E.↗
NASA NTRS2002

Firewall Traversal for CORBA Applications Using an Implementation of Bidirectional IIOP in MICO

The Object Management Group (OMG) has added specifications to the General Inter-ORB Protocol (GIOP 1.2), specifically the Internet Inter-ORB Protocol (IIOP 1.2), that allow servers and clients on opposing sides of a firewall to reverse roles and still communicate freely. This addition to the GIOP specifications is referred to as Bidirectional GIOP. The implementation of these specifications as applied to communication over TCP/IP connections is referred to as 'Bidirectional Internet Inter-ORB Protocol' or BiDirIIOP. This paper details the implementation and testing of the BiDirIIOP Specification in an open source ORB, MICO, that did not previously support Bidirectional GIOP. It also provides simple contextual information and a description of the OMG GIOP/IIOP messaging protocols.

Griffin, Robert I.↗