27,342 research outputs found
Multiple pass reimaging optical system
An optical imaging system for enabling nonabsorbed light imaged onto a photodetective surface to be collected and reimaged one or more times onto that surface in register with the original image. The system includes an objective lens, one or more imaging lenses, one or more retroreflectors and perhaps a prism for providing optical matching of the imaging lens focal planes to the photo detective surface
Seismicity investigations in the Cascade Mountains and vicinity, Oregon, 1 May 1969 - 30 April 1970
Seismicity in Cascade Mountains and vicinity, Orego
Extension and application of a sequential estimator
Improved sequential estimation technique for nonlinear time varying system
Development of Replacement Heifers using Combinations of Three Forage Types and Feed Supplements (with or without Broiler Litter)
The proper management of replacement heifers is an essential component of successful cow/calf operations. The level of management and nutrition applied to replacement heifers as calves and yearlings can impact their subsequent reproductive performance and productivity
Analytical study of a free-wing/free-trimmer concept
The free-wing/free-trimmer is a NASA-Conceived extension of the free-wing concept intended to permit the use of high-lift flaps. Wing pitching moments are balanced by a smaller, external surface attached by a boom or equivalent structure. The external trimmer is, itself, a miniature free wing, and pitch control of the wing-trimmer assembly is effected through a trailing-edge control tab on the trimmer surface. The longitudinal behavior of representative small free-wing/free-trimmer aircraft was analyzed. Aft-mounted trimmer surfaces are found to be superior to forward trimmers, although the permissible trimmer moment arm is limited, in both cases, by adverse dynamic effects. Aft-trimmer configurations provide excellent gust alleviation and meet fundamental stick-fixed stability criteria while exceeding the lift capabilities of pure free-wing configurations
Analysis of the linearity characteristics, tape recorders and compensation effects in the FM/FM telemetry system
Linearity characteristics, tape recorder effects, and tape speed compensation effects in FM/FM TELEMETRY syste
Semiclassical charged black holes with a quantized massive scalar field
Semiclassical perturbations to the Reissner-Nordstrom metric caused by the
presence of a quantized massive scalar field with arbitrary curvature coupling
are found to first order in \epsilon = \hbar/M^2. The DeWitt-Schwinger
approximation is used to determine the vacuum stress-energy tensor of the
massive scalar field. When the semiclassical perturbation are taken into
account, we find extreme black holes will have a charge-to-mass ratio that
exceeds unity, as measured at infinity. The effects of the perturbations on the
black hole temperature (surface gravity) are studied in detail, with particular
emphasis on near extreme ``bare'' states that might become precisely zero
temperature ``dressed'' semiclassical black hole states. We find that for
minimally or conformally coupled scalar fields there are no zero temperature
solutions among the perturbed black holes.Comment: 19 pages; 1 figure; ReVTe
Atomic and Molecular Opacities for Brown Dwarf and Giant Planet Atmospheres
We present a comprehensive description of the theory and practice of opacity
calculations from the infrared to the ultraviolet needed to generate models of
the atmospheres of brown dwarfs and extrasolar giant planets. Methods for using
existing line lists and spectroscopic databases in disparate formats are
presented and plots of the resulting absorptive opacities versus wavelength for
the most important molecules and atoms at representative temperature/pressure
points are provided. Electronic, ro-vibrational, bound-free, bound-bound,
free-free, and collision-induced transitions and monochromatic opacities are
derived, discussed, and analyzed. The species addressed include the alkali
metals, iron, heavy metal oxides, metal hydrides, , , , ,
, , , and representative grains. [Abridged]Comment: 28 pages of text, plus 22 figures, accepted to the Astrophysical
Journal Supplement Series, replaced with more compact emulateapj versio
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Modification of cellulose normally synthesizied by cellulose-producing microorganisms
The present invention involves a process for screening for and isolating spontaneously occurring or induced cellulose II-producing microorganisms. The process comprises a series of steps in various embodiments. Initially, cellulose-producing microorganisms from a first culture are plated out on a nutrient agar plate. The nutrient agar plate is then incubated to facilitate formation of colonies from single microorganisms. Samples of liquid nutrient medium are then inoculated with microorganisms from colonies having a smooth configuration, as compared to the usual rough colony configuration. The inoculated samples are then aerobically incubated to facilitate microorganism proliferation and pellicle formation. From these incubated samples are selected microorganisms, which, after a cultivation period, have proliferated but not formed a pellicle. Said selected microorganisms produce cellulose II instead of the cellulose I produced by pellicle-forming organisms.Board of Regents, University of Texas Syste
Cosmological Supergravity from a Massive Superparticle and Super Cosmological Black Holes
We describe in superspace a classical theory of two dimensional
dilaton supergravity with a cosmological constant, both with and without
coupling to a massive superparticle. We give general exact non-trivial
superspace solutions for the compensator superfield that describes the
supergravity in both cases. We then use these compensator solutions to
construct models of two-dimensional supersymmetric cosmological black holes.Comment: 20 pages, Late
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