4,819 research outputs found
Outsourcing the Human Resource Function: Environmental and Organizational Characteristics that Affect HR Performance
A theoretical model is presented that identifies environmental and organizational characteristics that affect human resource (HR) performance in an organization. Specifically, we address the issue of when and under what circumstances does HR outsourcing contribute value to the firm by attempting to identify environmental and organizational characteristics that affect HR department performance and how HR outsourcing mediates that relationship. We propose that supplier competition in the HR provider market has a direct effect on the amount of HR outsourcing which in turn has a direct effect on HR performance. Environmental uncertainty (primary, competitive, and supplier) is proposed to moderate the relationship between amount of HR outsourcing and HR performance while asset specificity is proposed to moderate the relationship between supplier competition and amount of HR outsourcing. An earlier version of this paper was presented at the Southwest Academy of Management meeting in Houston, Texas, March, 2003, and received the 2003 Irwin/McGraw-Hill Distinguished Paper Awar
zCOSMOS: A large VLT/VIMOS redshift survey covering 0 < z < 3 in the COSMOS field
zCOSMOS is a large-redshift survey that is being undertaken in the COSMOS field using 600 hr of observation
with the VIMOS spectrograph on the 8 m VLT. The survey is designed to characterize the environments of COSMOS
galaxies from the 100 kpc scales of galaxy groups up to the 100 Mpc scale of the cosmic web and to produce diagnostic
information on galaxies and active galactic nuclei. The zCOSMOS survey consists of two parts: (1) zCOSMOSbright,
a magnitude-limited I-band I_(AB) < 22.5 sample of about 20,000 galaxies with 0.1 < z < 1.2 covering the whole
1.7 deg^2 COSMOS ACS field, for which the survey parameters at z ~ 0.7 are designed to be directly comparable to
those of the 2dFGRS at z ~ 0.1; and (2) zCOSMOS-deep, a survey of approximately 10,000 galaxies selected through
color-selection criteria to have 1.4 < z < 3.0, within the central 1 deg^2. This paper describes the survey design and the
construction of the target catalogs and briefly outlines the observational program and the data pipeline. In the first
observing season, spectra of 1303 zCOSMOS-bright targets and 977 zCOSMOS-deep targets have been obtained.
These are briefly analyzed to demonstrate the characteristics that may be expected from zCOSMOS, and particularly
zCOSMOS-bright, when it is finally completed between 2008 and 2009. The power of combining spectroscopic and
photometric redshifts is demonstrated, especially in correctly identifying the emission line in single-line spectra and in
determining which of the less reliable spectroscopic redshifts are correct and which are incorrect. These techniques
bring the overall success rate in the zCOSMOS-bright so far to almost 90% and to above 97% in the 0.5 < z < 0.8
redshift range. Our zCOSMOS-deep spectra demonstrate the power of our selection techniques to isolate high-redshift
galaxies at 1.4 < z < 3.0 and of VIMOS to measure their redshifts using ultraviolet absorption lines
Bostonia. Volume 1
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
THE CANADA-FRANCE REDSHIFT SURVEY IX: HST Imaging of High-Redshift Field Galaxies
HST B and I images are presented of 32 CFRS galaxies with secure redshifts in
the range 0.5 < z < 1.2. These galaxies exhibit the same range of morphological
types as seen locally, i.e., ellipticals, spirals and irregulars. The galaxies
look far less regular in the images (rest-frame ultraviolet) than at longer
wavelengths, underlining the fact that optical images of galaxies at still
higher redshift should be interpreted with caution. Quantitative analyses of
the galaxies yield disk sizes, bulge fractions, and colors for each component.
At these redshifts, galaxy disks show clear evidence for surface brightness
evolution. The mean rest-frame central surface brightness of the disks of
normal late-type galaxies is mu_{AB}(B)=20.2 \pm 0.25 mag arcsec^{-2}, about
1.2 mag brighter than the Freeman (1970) value. Some degree of peculiarity is
measurable in 10 (30%) of the galaxies and 4 (13%) show clear signs of
interaction/mergers. There are 9 galaxies (30%) dominated by blue compact
components. These components, which appear to be related to star formation,
occur most often in peculiar/asymmetric galaxies (some of which appear to be
interacting), but a few are in otherwise normal galaxies. Thus, of the galaxies
bluer than present-day Sb, one-third are "blue nucleated galaxies", and half
are late-type galaxies with disks which are significantly brighter than normal
galaxies at z=0. Taken together, these two effects must be responsible for much
of the observed evolution of the luminosity function of blue galaxies.Comment: uuencoded compressed postscript, 8 pages, 1 table + 5 figures in a
separate part. Also available at http://www.astro.utoronto.ca/~lilly/CFRS/ .
Accepted for publication in ApJ Letter
The Canada-France Redshift Survey XII: Nature of emission-line field galaxy population up to z = 0.3
We present a spectroscopic study of the 138 field galaxies to a redshift z =
0.3 from the I-selected Canada-France Redshift Survey. 117(85%) spectra exhibit
at least H alpha in emission, the remaining 21(15%) are purely absorption-line
spectra. We focus our analysis on spectra with H alpha and H beta in emission,
accounting for about half of this low-z sample, which we classify using
emission-line ratio diagrams. Using photoionization models, we determine the
extreme boundaries of H II galaxies in these diagnostic diagrams, and
demonstrate that the emission-line ratios of a significant fraction of galaxies
require harder photoionization sources than massive O stars. We find that about
17% of the field galaxies have emission-line ratios consistent with active
galaxies, e.g., Seyfert 2 or LINERs. After correcting for stellar absorption
under the Balmer lines, we conclude that the fraction of such galaxies is at
least 8% of the field galaxy population at z < 0.3.Comment: uuencoded compressed latex file including tables but not figures,
yielding 14 pages. The full text and figures are also available at
http://www.dao.nrc.ca/DAO/SCIENCE/science.html ,
http://www.astro.utoronto.ca/~lilly/CFRS/papers.html , and by anonymous ftp
at ftp://ast.cam.ac.uk/pub/lt . Accepted by MNRA
Undoped Electron-Hole Bilayers in a GaAs/AlGaAs Double Quantum Well
We present the fabrication details of completely undoped electron-hole
bilayer devices in a GaAs/AlGaAs double quantum well heterostructure with a 30
nm barrier. These devices have independently tunable densities of the
two-dimensional electron gas and two-dimensional hole gas. We report
four-terminal transport measurements of the independently contacted electron
and hole layers with balanced densities from cm down
to cm at . The mobilities can exceed cm V s for electrons and
cm V s for holes.Comment: 3 pages, 3 figure
Coherent Propagation of Spin Helices in a Quantum-Well Confined Electron Gas
We use phase-resolved transient grating spectroscopy to measure the
propagation of spin helices in a high mobility -GaAs/AlGaAs quantum well
with an applied in-plane electric field. At relatively low fields helical modes
crossover from overdamped excitations where the spin-precession period exceeds
the spin lifetime, to a regime of coherent propagation where several
spin-precession periods can be observed. We demonstrate that the envelope of a
spin polarization packet reaches a current-driven velocity of 10 cm
s in an applied field of 70 V cm
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