16,076 research outputs found
SRB-3D Solid Rocket Booster performance prediction program. Volume 1: Engineering description/users information manual
The modified Solid Rocket Booster Performance Evaluation Model (SRB-3D) was developed as an extension to the internal ballistics module of the SRB-2 performance program. This manual contains the engineering description of SRB-3D which describes the approach used to develop the 3D concept and an explanation of the modifications which were necessary to implement these concepts
Tunneling between Dilute GaAs Hole Layers
We report interlayer tunneling measurements between very dilute
two-dimensional GaAs hole layers. Surprisingly, the shape and
temperature-dependence of the tunneling spectrum can be explained with a Fermi
liquid-based tunneling model, but the peak amplitude is much larger than
expected from the available hole band parameters. Data as a function of
parallel magnetic field reveal additional anomalous features, including a
recurrence of a zero-bias tunneling peak at very large fields. In a
perpendicular magnetic field, we observe a robust and narrow tunneling peak at
total filling factor , signaling the formation of a bilayer quantum
Hall ferromagnet.Comment: Revised to include additional data, new discussion
Performance analysis of grazing incidence imaging systems
An exact expression relating the coordinates of a point on the incident ray, a point of reflection from an arbitrary surface, and a point on the reflected ray is derived. The exact relation is then specialized for the case of grazing incidence, and first order and third order systematic analyses are carried out for a single reflective surface and then for a combination of two surfaces. The third order treatment yields a complete set of primary aberrations for single element and two element systems. The importance of a judicious choice for a coordinate system in showing field curvature to clearly be the predominant aberration for a two element system is discussed. The validity of the theory is verified through comparisons with the exact ray trace results for the case of the telescope
A preliminary discussion of gravitational physics experiments for the Spacelab era
An overview of past, present, and proposed future experiments in gravitational physics is given. These experiments are concerned with the measurement of relativistic gravity effects to test theories of gravitation. Certain experiments which could be performed on shuttle and Spacelab missions and the potential of Spacelab for gravitation physics research are discussed
On the (de)stabilizing effects of news shocks
This paper analyzes the impacts of news shocks on macroeconomic volatility. Whereas in any purely forward-looking model, such as the baseline New Keynesian model, anticipation amplifies volatility, we obtain ambiguous results when including a backward-looking component. In addition to these theoretical findings, we use the estimated model of Smets and Wouters (2003) to provide numerical evidence that news shocks increase the volatility of key macroeconomic variables in the euro area when compared to unanticipated shocks. --Anticipated shocks,business cycles,volatility
Rational expectations models with anticipated shocks and optimal policy: a general solution method and a new Keynesian example
The purpose of this paper is to show how to solve linear dynamic rational expectations models with anticipated shocks by using the generalized Schur decomposition method. Furthermore, we determine the optimal unrestricted and restricted policy responses to anticipated shocks. We demonstrate our solution method by means of a micro-founded hybrid New Keynesian model and show that anticipated cost-push shocks entail higher welfare losses than unanticipated shocks of equal size. --Anticipated Shocks,Optimal Monetary Policy,Rational Expectations,Generalized Schur Decomposition,Welfare Effects
Oil Price Shocks and Currency Denomination (A revised version of EWP 2005-01)
The paper analyzes the dynamic effects of anticipated price increases of imported raw materials upon two large open economies. It is assumed that the economies have an asymmetric macroeconomic structure on the supply side and are dependent upon a small third country for oil or raw materials imports. The dynamic behavior of several macroeconomic variables is discussed both under US dollar and Euro-currency denomination. It is shown that with Euro-currency denominated oil the stagnationary effects of oil price increases upon both the domestic and foreign economy are reduced. The paper also discusses several monetary policy responses to oil price shocks. --oil price shocks,international policy coordination,currency denomination
Solution of RE Models with Anticipated Shocks and Optimal Policy
The purpose of this paper is to solve linear dynamic rational expectations models with anticipated shocks by using the generalized Schur decomposition method. We also determine the optimal unrestricted and restricted policy responses to temporary as well as permanent shocks which both are anticipated by the public. In particular, our method is useful for the analysis of optimal monetary policy in New Keynesian dynamic general equilibrium models. --Anticipated Shocks,Optimal Monetary Policy,Rational Expectations,Generalized Schur Decomposition
First results of observations of transient pulsar SAXJ2103.5+4545 with the INTEGRAL observatory
We present preliminary results of observations of X-ray pulsar SAX
J2103.5+4545 with INTEGRAL observatory in Dec 2002. Maps of this sky region in
energy bands 3-10, 15-40, 40-100 and 100-200 keV are presented. The source is
significantly detected up to energies of keV. The hard X-ray flux in
the 15-100 energy band is variable, that could be connected with the orbital
phase of the binary system. We roughly reconstructed the source spectrum using
its comparison to that of Crab nebula. It is shown that the parameters of the
source spectrum in 18-150 keV energy range are compatible with that obtained
earlier by RXTE observatoryComment: 5 pages, 4 figures, accepted for publication in the Astronomy Letter
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