Temporal Variation in the Interest-Rate Response to Money Announcements

A number of studies find significant temporal variation in the interest-rate response to money announcement surprises. An unresolved question, however, is whether the response changes immediately as different policy regimes are adopted, or whether the change is gradual reflecting the establishment of Federal Reserve credibility. This paper conducts tests that allow for both discrete shifts in the interest-rate response to money announcements and a gradual evolution in this response. The evidence is consistent with the hypothesis that temporal variation in the interest-rate response is limited to discrete shifts in October 1979, October 1982, arid February 1984.

cRIsp: Crowdsourcing Representation Information to Support Preservation

In this paper, we describe a new collaborative approach to the collection of representation information to ensure long term access to digital content. Representation information is essential for successful rendering of digital content in the future. Manual collection and maintenance of representation information has so far proven to be highly resource intensive and is compounded by the massive scale of the challenge, especially for repositories with no format limitations. This solution combats these challenges by drawing upon the wisdom and knowledge of the crowd to identify online sources of representation information, which are then collected, classified, and managed using existing tools. We suggest that nominations can be harvested and preserved by participating established web archives, which themselves could obviously benefit from such extensive collections. This is a low cost, low resource approach to collecting essential representation information of widespread relevance

Disorder effect in low dimensional superconductors

The quasiparticle density of states (DOS), the energy gap, the superfluid density $\rho_s$, and the localization effect in the s- and d-wave superconductors with non-magnetic impurity in two dimensions (2D) are studied numerically. For strong (unitary) scatters, we find that it is the range of the scattering potential rather than the symmetry of the superconducting pairing which is more important in explaining the impurity dependences of the specific heat and the superconducting transition temperature in Zn doped YBCO. The localization length is longer in the d-wave superconducting state than in the normal state, even in the vicinity of the Fermi energy.Comment: 2 pages, uuencoded compressed postscript file, IRC-940610

The Second Galex Ultraviolet Variability (GUVV-2) Catalog

We present the second Galaxy Evolution Explorer (GALEX) Ultraviolet Variability (GUVV-2) Catalog that contains information on 410 newly discovered time-variable sources gained through simultaneous near (NUV 1750-2750A) and far (FUV 1350-1750A) ultraviolet photometric observations. Source variability was determined by comparing the NUV and/or FUV fluxes derived from orbital exposures recorded during a series of multiple observational visits to 169 GALEX fields on the sky. These sources, which were contained within a sky-area of 161 square deg, varied on average by amplitudes of NUV = 0.6 mag and FUV = 0.9 mag during these observations. Of the 114 variable sources in the catalog with previously known identifications, 67 can be categorized as being active galaxies (QSO's, Seyfert 1 or BL Lac objects). The next largest groups of UV variables are RR Lyrae stars, X-ray sources and novae. By using a combination of UV and visible color-color plots we have been able to tentatively identify 36 possible RR Lyrae and/or Delta Scuti type stars, as well as 35 probable AGN's, many of which may be previously unidentified QSO's or blazars. Finally, we show data for 3 particular variable objects: the contact binary system of SDSS J141818.97+525006.7, the eclipsing dwarf nova system of IY UMa and the highly variable unidentified source SDSS J104325.06+563258.1.Comment: Astronomical Journal accepte

GALEX ultraviolet observations of stellar variability in the Hyades and Pleiades clusters

We present GALEX near ultraviolet (NUV:1750 - 2750A) and far ultraviolet (FUV: 1350 - 1750A) imaging observations of two 1.2 degree diameter fields in the Hyades and Pleiades open clusters in order to detect possible UV variability of the member stars. We have performed a detailed software search for short-term UV flux variability during these observations of the approx 400 sources detected in each of the Hyades and Pleiades fields to identify flare-like (dMe) stellar objects. This search resulted in the detection of 16 UV variable sources, of which 13 can be directly associated with probable M-type stars. The other UV sources are G-type stars and one newly discovered RR Lyrae star, USNOB1.0 1069-0046050, of period 0.624 day and distance 4.5-7.0 kpc. Light curves of photon flux versus time are shown for 7 flare events recorded on six probable dMe stars. UV energies for these flares span the range 2E27 to 5E29 erg, with a corresponding NUV variability change of 1.82 mag. Only one of these flare events (on the star Cl* Melotte 25 LH129) can definitely be associated with an origin on a member the Hyades cluster itself. Finally, many of our M-type candidates show long periods of enhanced UV activity but without the associated rapid increase in flux that is normally associated with a flare event. However, the total UV energy output during such periods of increased activity is greater than that of many short-term UV flares. These intervals of enhanced low-level UV activity concur with the idea that, even in quiescence, the UV emission from dMe stars may be related to a superposition of many small flare events possessing a wide range of energies.Comment: PASP Submitte

Calculating the inherent visual structure of a landscape (inherent viewshed) using high-throughput computing

This paper describes a method of calculating the inherent visibility at all locations in a landscape (‘total viewshed’) by making use of redundant computer cycles. This approach uses a simplified viewshed program that is suitable for use within a distributed environment, in this case managed by the Condor system. Distributing the calculation in this way reduced the calculation time of our example from an estimated 34 days to slightly over 25 hours using a cluster of 43 workstations. Finally, we discuss the example ‘total viewshed’ raster for the Avebury region, and briefly highlight some of its implications

Asset Building in Low-Income Communities of Color, Part 1

Examines practices and policies in states rated high on the Corporation for Enterprise Development's scorecard for asset building in poor communities of color. Analyzes socioeconomic, legislative, and other factors believed to support asset building