4,574 research outputs found
Study of advanced bladder technology, OF2 diborane Final report, 2 Sep. 1969 - 1 Jul. 1970
Development and characteristics of elastomeric materials for positive expulsion bladder
Satellite microwave observations of soil moisture variations
The electrically scanning microwave radiometer (ESMR) on the Nimbus 5 satellite was used to observe microwave emissions from vegetated and soil surfaces over an Illinois-Indiana study area, the Mississippi Valley, and the Great Salt Lake Desert in Utah. Analysis of microwave brightness temperatures (T sub B) and antecedent rainfall over these areas provided a way to monitor variations of near-surface soil moisture. Because vegetation absorbs microwave emission from the soil at the 1.55 cm wavelength of ESMR, relative soil moisture measurements can only be obtained over bare or sparsely vegetated soil. In general T sub B increased during rainfree periods as evaporation of water and drying of the surface soil occurs, and drops in T sub B are experienced after significant rainfall events wet the soil. Microwave observations from space are limited to coarse resolutions (10-25 km), but it may be possible in regions with sparse vegetation cover to estimate soil moisture conditions on a watershed or agricultural district basis, particularly since daily observations can be obtained
Treatment of metal surfaces for use with space storable propellants - A critical survey
Treatment of metallic surfaces for use with space storable propellant
Scientific Objectives for UV/Visible Astrophysics Investigations: A Summary of Responses by the Community (2012)
Following several recommendations presented by the Astrophysics Decadal
Survey 2010 centered around the need to define "a future ultraviolet-optical
space capability," on 2012 May 25, NASA issued a Request for Information (RFI)
seeking persuasive ultraviolet (UV) and visible wavelength astrophysics science
investigations. The goal was to develop a cohesive and compelling set of
science objectives that motivate and support the development of the next
generation of ultraviolet/visible space astrophysics missions. Responses were
due on 10 August 2012 when 34 submissions were received addressing a number of
potential science drivers. A UV/visible Mission RFI Workshop was held on 2012
September 20 where each of these submissions was summarized and discussed in
the context of each other. We present a scientific analysis of these
submissions and presentations and the pursuant measurement capability needs,
which could influence ultraviolet/visible technology development plans for the
rest of this decade. We also describe the process and requirements leading to
the inception of this community RFI, subsequent workshop and the expected
evolution of these ideas and concepts for the remainder of this decade.Comment: 22 pages, 1 figure, 3 table
Existence theorems in the geometrically non-linear 6-parametric theory of elastic plates
In this paper we show the existence of global minimizers for the
geometrically exact, non-linear equations of elastic plates, in the framework
of the general 6-parametric shell theory. A characteristic feature of this
model for shells is the appearance of two independent kinematic fields: the
translation vector field and the rotation tensor field (representing in total 6
independent scalar kinematic variables). For isotropic plates, we prove the
existence theorem by applying the direct methods of the calculus of variations.
Then, we generalize our existence result to the case of anisotropic plates. We
also present a detailed comparison with a previously established Cosserat plate
model.Comment: 19 pages, 1 figur
On Chromospheric Variations Modeling for Main-Sequence Stars of G and K Spectral Classes
We present a method of chromospheric flux simulation for 13 late-type
main-sequence stars. These Sun-like stars have well-determined cyclic flux
variations similar to 11 yr solar activity cycle. Our flux prediction is based
on chromospheric HK emission time series measurements from Mount Wilson
Observatory and comparable solar data. We show that solar three - component
modeling explains well the stellar observations. We find that the 10 - 20% of K
- stars disc surfaces are occupied by bright active regions.Comment: 8 pages, 2 figure
Evaluation of ozone difluoride as a liquid propellant additive Final report
Ozone difluoride evaluated as liquid propellant additiv
Simulation and Analysis Chain for Acoustic Ultra-high Energy Neutrino Detectors in Water
Acousticneutrinodetectionisapromisingapproachforlarge-scaleultra-highenergyneutrinodetectorsinwater.In
this article, a Monte Carlo simulation chain for acoustic neutrino detection
devices in water will be presented. The simulation chain covers the generation
of the acoustic pulse produced by a neutrino interaction and its propagation to
the sensors within the detector. Currently, ambient and transient noise models
for the Mediterranean Sea and simulations of the data acquisition hardware,
equivalent to the one used in ANTARES/AMADEUS, are implemented. A pre-selection
scheme for neutrino-like signals based on matched filtering is employed, as it
is used for on-line filtering. To simulate the whole processing chain for
experimental data, signal classification and acoustic source reconstruction
algorithms are integrated in an analysis chain. An overview of design and
capabilities of the simulation and analysis chain will be presented and
preliminary studies will be discussed.Comment: 6 pages, 5 figures, ARENA 2012. arXiv admin note: substantial text
overlap with arXiv:1304.057
GRAND MAL SEIZURE AFTER EXTRADURAL MORPHINE ANALGESIA
SUMMARY Following an elective Caesarean section under extradural anaesthesia, a 30-yr-old known epileptic woman (gravida 4, para 3) developed a tonic-clonic seizure, 6 h after the administration of morphine 3 mg into the extradural space. Possible aetiological factors are discusse
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