1,723 research outputs found
An evaluation of the relative fire hazards of jet A and jet B for commercial flight
The relative fire hazards of Jet A and Jet B aircraft fuels are evaluated. The evaluation is based on a consideration of the presence of and/or the generation of flammable mixtures in fuel systems, the ignition characteristics, and the flame propagation rates for the two fuel types. Three distinct aircraft operating regimes where fuel type may be a factor in fire hazards are considered. These are: (1) ground handling and refueling, (2) flight, and (3) crash. The evaluation indicates that the overall fire hazards for Jet A are less than for Jet B fuel
Spectral emittance of soot
Spectral emittance of thin soot layers on transparent substrate
Nonsimultaneity and Futures Option Pricing: Simulation and Empirical Evidence
Empirical tests of option pricing models are joint tests of the 'correctness' of the model, the efficiency of the market and the simultaneity of price observations. Some degree of nonsimultaeity can be expected in all but the most liquid markets and is therefore evident in many non-US markets. Simulation results indicate that nonsimultaneity is potentially a significant problem in empirical tests of futures option pricing models. Empirical results using Australian data show that a five-minute window for matching transactions does not remove the nonsimultaneity bias for near-the-money and out-of-the money options. A more accurate matching may therefore be required. The nonsimultaneity bias is effectively removed if a five-minute window is employed for in-the-money options.Nonsimultaneity; Futures option; Mispricing
A new red giant-based distance modulus of 13.3 Mpc to the Antennae galaxies and its consequences
The Antennae galaxies are the closest example of an ongoing major galaxy
merger, and thereby represent a unique laboratory for furthering the
understanding of the formation of exotic objects (e.g., tidal dwarf galaxies,
ultra-luminous X-ray sources, super-stellar clusters, etc). In a previous paper
HST/WFPC2 observations were used to demonstrate that the Antennae system might
be at a distance considerably less than that conventionally assumed in the
literature. Here we report new, much deeper HST/ACS imaging that resolves the
composite stellar populations, and most importantly, reveals a well-defined red
giant branch. The tip of this red giant branch (TRGB) is unambiguously detected
at Io(TRGB)=26.65 +/- 0.09 mag. Adopting the most recent calibration of the
luminosity of the TRGB then yields a distance modulus for the Antennae of
(m-M)o= 30.62 +/- 0.17 corresponding to a distance of 13.3 +/- 1.0 Mpc. This is
consistent with our earlier result, once the different calibrations for the
standard candle are considered. We briefly discuss the implications of this now
well determined shorter distance.Comment: 11 pages, 3 figures, accepted for publication in the Ap
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