387 research outputs found
Viper cabin-fuselage structural design concept with engine installation and wing structural design
This report describes the process and considerations in designing the cabin, nose, drive shaft, and wing assemblies for the 'Viper' concept aircraft. Interfaces of these assemblies, as well as interfaces with the sections of the aircraft aft of the cabin, are also discussed. The results of the design process are included. The goal of this project is to provide a structural design which complies with FAR 23 requirements regarding occupant safety, emergency landing loads, and maneuvering loads. The design must also address the interfaces of the various systems in the cabin, nose, and wing, including the drive shaft, venting, vacuum, electrical, fuel, and control systems. Interfaces between the cabin assembly and the wing carrythrough and empennage assemblies were required, as well. In the design of the wing assemblies, consistency with the existing cabin design was required. The major areas considered in this report are materials and construction, loading, maintenance, environmental considerations, wing assembly fatigue, and weight. The first three areas are developed separately for the nose, cabin, drive shaft, and wing assemblies, while the last three are discussed for the entire design. For each assembly, loading calculations were performed to determine the proper sizing of major load carrying components. Table 1.0 lists the resulting margins of safety for these key components, along with the types of the loads involved, and the page number upon which they are discussed
Bioturbation artifacts in zero-age sediments
Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 24 (2009): PA4212, doi:10.1029/2008PA001727.Most seafloor sediments are dated with radiocarbon, and the sediment is assumed to be zero-age (modern) when the signal of atmospheric testing of nuclear weapons is present (Fraction modern (Fm) > 1). Using a simple mass balance, we show that even with Fm > 1, half of the planktonic foraminifera at the seafloor can be centuries old, because of bioturbation. This calculation, and data from four core sites in the western North Atlantic indicate that, first, during some part of the Little Ice Age (LIA) there may have been more Antarctic Bottom Water than today in the deep western North Atlantic. Alternatively, bioturbation may have introduced much older benthic foraminifera into surface sediments. Second, paleo-based warming of Sargasso Sea surface waters since the LIA must lag the actual warming because of bioturbation of older and colder foraminifera.This work was funded in part by the Gary Comer Foundation and by NSF grant 0214144. A portion of this work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344
Two-pion correlations in Au+Au collisions at 10.8 GeV/c per nucleon
Two-particle correlation functions for positive and negative pions have been
measured in Au+Au collisions at 10.8~GeV/c per nucleon. The data were analyzed
using one- and three-dimensional correlation functions. From the results of the
three-dimensional fit the phase space density of pions was calculated. It is
consistent with local thermal equilibrium.Comment: 5 pages RevTeX (including 3 Figures
Proton and Pion Production in Au+Au Collisions at 10.8A GeV/c
We present proton and pion tranverse momentum spectra and rapidity
distributions for Au+Au collisions at 10.8A GeV/c. The proton spectra exhibit
collective transverse flow effects. Evidence of the influence of the Coulomb
interaction from the fireball is found in the pion transverse momentum spectra.
The data are compared with the predictions of the RQMD event generator.Comment: plain tex (revtex), 24 pages Submitted to Phys. Rev.
Directed flow of antiprotons in Au+Au collisions at AGS
Directed flow of antiprotons is studied in Au+Au collisions at a beam
momentum of 11.5A GeV/c. It is shown that antiproton directed flow is
anti-correlated to proton flow. The measured transverse momentum dependence of
the antiproton flow is compared with predictions of the RQMD event generator.Comment: 16 pages, 6 figure
Two-Proton Correlations from 14.6A GeV/c Si+Pb and 11.5A GeV/c Au+Au Central Collisions
Two-proton correlation functions have been measured in Si+Pb collisions at
14.6A GeV/c and Au+Au collisions at 11.5A GeV/c by the E814/E877 collaboration.
Data are compared with predictions of the transport model RQMD and the source
size is inferred from this comparison. Our analysis shows that, for both
reactions, the characteristic size of the system at freeze-out exceeds the size
of the projectile, suggesting that the fireball created in the collision has
expanded. For Au+Au reactions, the observed centrality dependence of the
two-proton correlation function implies that more central collisions lead to a
larger source sizes.Comment: RevTex, 12 pages, 5 figure
Charged Particle Pseudorapidity Distributions in Au+Al, Cu, Au, and U Collisions at 10.8 AGeV/c
We present the results of an analysis of charged particle pseudorapidity
distributions in the central region in collisions of a Au projectile with Al,
Cu, Au, and U targets at an incident energy of 10.8~GeV/c per nucleon. The
pseudorapidity distributions are presented as a function of transverse energy
produced in the target or central pseudorapidity regions. The correlation
between charged multiplicity and transverse energy measured in the central
region, as well as the target and projectile regions is also presented. We give
results for transverse energy per charged particle as a function of
pseudorapidity and centrality.Comment: 31 pages + 12 figures (compressed and uuencoded by uufiles), LATEX,
Submitted to PR
Proton and Pion Production Relative to the Reaction Plane in Au + Au Collisions at AGS Energies
Results are presented of an analysis of proton and charged pion azimuthal
distributions measured with respect to the reaction plane in Au + Au collisions
at a beam momentum of about 11 AGeV/c. The azimuthal anisotropy is studied as a
function of particle rapidity and transverse momentum for different
centralities of the collisions. The triple differential (in rapidity,
transverse momentum, and azimuthal angle) distributions are reconstructed. A
comparison of the results with a previous analysis of charged particle and
transverse energy flow as well as with model predictions is presented.Comment: 23 pages (LaTeX), 12 figure
Hadron yields and spectra in Au+Au collisions at the AGS
Inclusive double differential multiplicities and rapidity density
distributions of hadrons are presented for 10.8 A GeV/c Au+Au collisions as
measured at the AGS by the E877 collaboration. The results indicate that large
amounts of stopping and collective transverse flow effects are present. The
data are also compared to the results from the lighter Si+Al system.Comment: 12 pages, latex, 10 figures, submitted to Nuclear Physics A (Quark
Matter 1996 Proceedings
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Easter lily growth and development
Production and marketing of the lily crop involves bulb growers, wholesale florists (jobbers), greenhouse forcers, and research horticulturists whose success depends in great measure on their knowledge of bulb physiology.
Our knowledge of the growth and development of the Easter lily and its storage and forcing requirements has increased greatly in the last 25 years, but the influences of field and climatic factors on yield and forcing performance have not been studied fully. Field, greenhouse, and controlled-environment facilities were used to determine plant/temperature relations in the phasic development of the Easter lily crop and its climatic adaptation. Weather monitoring (soil and air temperature) and plant growth analysis were used to evaluate the feasibility of predicting bulb yield, dormancy, maturity, and greenhouse forcing performance. The modifying influence of cultural practices on climate responses further illustrates the complexity of predictive instruments.Published July 1985. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
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