1,960,209 research outputs found
Pion Charge Exchange on Deuterium
We investigate quantum corrections to a classical intranuclear cascade
simulation of pion single charge exchange on the deuteron. In order to separate
various effects the orders of scattering need to be distinguished and, to that
end, we develop signals for each order of scattering corresponding to
quasi-free conditions. Quantum corrections are evaluated for double scattering
and are found to be large. Global agreement with the data is good.Comment: 30 pages, 12 figure
Dynamic tooth loads and stressing for high contact ratio spur gears
An analysis and computer program were developed for calculating the dynamic gear tooth loading and root stressing for high contact ratio gearing (HCRG) as well as LCRG. The analysis includes the effects of the variable tooth stiffness during the mesh, tooth profile modification, and gear errors. The calculation of the tooth root stressing caused by the dynamic gear tooth loads is based on a modified Heywood gear tooth stress analysis, which appears more universally applicable to both LCRG and HCRG. The computer program is presently being expanded to calculate the tooth contact stressing and PV values. Sample application of the gear program to equivalent LCRG (1.566 contact ratio) and HCRG (2.40 contact ratio) revealed the following: (1) the operating conditions and dynamic characteristics of the gear system an affect the gear tooth loading and root stressing, and therefore, life significantly; (2) the length of the profile modification affect the tooth loading and root stressing significantly, the amount depending on the applied load, speed, and contact ratio; and (3) the effect of variable tooth stiffness is small, shifting and increasing the response peaks slightly from those for constant tooth stiffness
Dual-mode operation of a neutron source, a concept
Pulsed neutron source operates in conjunction with a photomultiplier tube coupled to a gamma ray scintillation crystal. This allows measurements of gamma radiation from both inelastic scattering and thermal neutron capture in a single experiment
Method and apparatus for making a heat insulating and ablative structure Patent
Method and apparatus for fabrication of heat insulating and ablative reentry structur
On Axiomatization of Inconsistency Indicators for Pairwise Comparisons
We examine the notion of inconsistency in pairwise comparisons and propose an
axiomatization which is independent of any method of approximation or the
inconsistency indicator definition (e.g., Analytic Hierarchy Process, AHP). It
has been proven that the eigenvalue-based inconsistency (proposed as a part of
AHP) is incorrect.Comment: Enhanced text, with 21 pages and 3 figures, proves that arbitrarily
inaccurate pairwise matrices are considered acceptable by theories with a
inconsistency based on the principal eigenvalue (e.g., AHP). CPC (corner
pairwise comparisons) matrix is the crucial part of this study as it
invalidates any eigenvalue-based inconsistency. All comments are highly
appreciate
K-Electron-Capture-to-Positron-Emission Ratio in the Decays of ^(15)O and ^(19)Ne
The K/β^+ ratio in the decays of ^(19)Ne and ^(15)O have been measured as (9.6 ± 0.3) × 10^(-4) and (10.7 ± 0.6) × 10^(-4), respectively. A gas-flow proportional counter, operating in anticoincidence with the surrounding plastic scintillator, was used. Theoretical K/β^+ ratios for ^(19)Ne and ^(15)O were computed, using exchange-overlap corrections calculated by Vatai and, separately, exchange corrections extrapolated from the results of Bahcall for 14 ≤ Z ≤ 37. The experimental results were found to be in better agreement with Vatai's calculations
A system of regional agricultural land use mapping tested against small scale Apollo 9 color infrared photography of the Imperial Valley (California)
System of regional agricultural land use mapping tested against Apollo 9 color infrared photography of Imperial Valley, Calif
On the origin of surface states in a correlated local-moment film
The electronic quasiparticle structure of a ferromagnetic local moment film
is investigated within the framework of the s-f model. For the special case of
a single electron in an otherwise empty energy band being exchange coupled to a
fully ordered localised spin system the problem can be solved exactly and, for
the spin-down electron, some marked correlation effects can be found. We extend
our model to incorporate the influence of the surface on the electronic
structure. Therefore we modify the hopping integrals in the vicinity of the
surface. This leads to the existence of surface states, both for the spin-up
and the spin-down spectral density of states. The interplay between the
modification of the hopping integrals and the existence of surface states and
correlation effects is discussed in detail.Comment: 9 pages, 9 figures, accepted for publication in European Physical
Journal
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