4,992 research outputs found
Adobe Flash as a medium for online experimentation: a test of reaction time measurement capabilities
Adobe Flash can be used to run complex psychological experiments over the Web. We examined the reliability of using Flash to measure reaction times (RTs) using a simple binary-choice task implemented both in Flash and in a Linux-based system known to record RTs with millisecond accuracy. Twenty-four participants were tested in the laboratory using both implementations; they also completed the Flash version on computers of their own choice outside the lab. RTs from the trials run on Flash outside the lab were approximately 20 msec slower than those from trials run on Flash in the lab, which in turn were approximately 10 msec slower than RTs from the trials run on the Linux-based system (baseline condition). RT SDs were similar in all conditions, suggesting that although Flash may overestimate RTs slightly, it does not appear to add significant noise to the data recorded
THE ROLE OF IMPORTS IN THE CHANGING NATURE OF THE U.S. FARM MACHINERY INDUSTRY
Agribusiness, International Relations/Trade,
Cutting simulation with consideration of the material hardening in the Shear Zone of AISI1045
By the use of high energy synchrotron X-ray diffraction it was possible to determine the stress state in the chip formation zone during orthogonal cutting of AISI1045. The analysis of the diffractograms showed a hardening of the material during the movement through the shear zone. For this reason nano indentation experiments on prepared chips have been carried out. With these experiments, the material hardening has been confirmed. The nano indentation experiments were reproduced by FEM simulations and it was possible to determine flow curves of the hardened material above the shear zone based on existing flow curves of AISI1045. Thus, cutting simulations have been carried out, which considered the material hardening in the shear zone. The simulation results were then compared with the results of the in-situ strain measurements
The frequency of antlerless females among Svalbard reindeer
The distribution of females with no, one and two antlers was recorded during July 1994 in Svalbard reindeer, Rangifer tarandus platyrhynchus, and compared wirh 1974 data from Reimers (1993) and Larsen (1977). On Reinsdyrflya, 50% of the females were anrlerless, 16% one antlered and 34% rwo antlered. In Nordenskiold Land, 2% of the females were antlerless, 1% one antlered and 97% two antlered. These percentages have not changed since Reimers' study in 1974 in Reinsdyrflya (Chi square 2= 1.16, P > 0.05) and Nordenskiold Land (Chi square 2 = 1.69, P > 0.05). The reason for the high frequency of anrlerless females on Reinsdyrflya is not understood
Classical heisenberg antiferromagnet away from the pyrochlore lattice limit: entropic versus energetic selection
The stability of the disordered ground state of the classical Heisenberg
pyrochlore antiferromagnet is studied within extensive Monte Carlo simulations
by introducing an additional exchange interaction that interpolates
between the pyrochlore lattice () and the face-centered cubic lattice
(). It is found that for as low as , the system is
long range ordered : the disordered ground state of the pyrochlore
antiferromagnet is unstable when introducing very small deviations from the
pure limit. Furthermore, it is found that the selected phase is a
collinear state energetically greater than the incommensurate phase suggested
by a mean field analysis. To our knowledge this is the first example where
entropic selection prevails over the energetic one.Comment: 5 (two-column revtex4) pages, 1 table, 7 ps/eps figures. Submitted to
Phys. Rev.
Observations of Chemically Enriched QSO Absorbers near z ~ 2.3 Galaxies: Galaxy-Formation Feedback Signatures in the IGM
We present a study of galaxies and intergalactic gas toward the z=2.73 quasar
HS1700+6416, to explore the effects of galaxy formation feedback on the IGM.
Our observations and ionization simulations indicate that the volume within
100-200 h_71^{-1} physical kpc of high-redshift galaxies contains very small,
dense, and metal-rich absorption-line regions. These systems often contain
shock-heated gas seen in OVI, and may exhibit [Si/C] abundance enhancements
suggestive of Type II supernova enrichment. We argue that the absorbers
resemble thin sheets or bubbles, whose physical properties can be explained
with a simple model of radiatively efficient shocks propegating through the
IGM. Their high metallicities suggest that these shocks are being expelled
from--rather than falling into--star forming galaxies. There is a dropoff in
the IGM gas density at galaxy impact parameters beyond ~300 physical kpc that
may trace boundaries of gas structures where the galaxies reside. The local
heavy-element enhancement covers 100-200 kpc; beyond this the observed
abundances blend into the general IGM. Supernova-driven winds or dynamical
stripping of interstellar gas appears to affect the IGM near massive galaxies,
even at R>~100 kpc. However, these feedback systems represent only a few
percent of the Lya forest mass at z~2.5. Their mass could be larger if the more
numerous metal-poor CIV systems at >~200 kpc are tepid remnants of very
powerful winds. Based on present observations it is not clear that this
scenario is to be favored over one involving pre-enrichment by smaller galaxies
at z>~6.Comment: Accepted for publication in the Astrophysical Journal. 26 pages
emulateapj, incl. 5 pages tables, 15 figure
Pyrochlore Antiferromagnet: A Three-Dimensional Quantum Spin Liquid
The quantum pyrochlore antiferromagnet is studied by perturbative expansions
and exact diagonalization of small clusters. We find that the ground state is a
spin-liquid state: The spin-spin correlation functions decay exponentially with
distance and the correlation length never exceeds the interatomic distance. The
calculated magnetic neutron diffraction cross section is in very good agreement
with experiments performed on Y(Sc)Mn2. The low energy excitations are
singlet-singlet ones, with a finite spin gap.Comment: 4 pages, 4 figure
Entrepreneurial Career Development: Using Human Capital, Social Capital, and Distance Education to Achieve Success
Individuals, especially women, must be increasingly entrepreneurial in the twenty-first century in order to achieve success. It is also important for women to take an entrepreneurial approach to career development. The first key component of an entrepreneurial approach to career development is investing in human capital. Continuous investment in human capital increases earning power, opens doors to professional opportunities, and contributes to career advancement. The second key component of an entrepreneurial approach to career development is investing in social capital. Women can increase their chances for professional success by developing networks that connect them to key individuals, assignments, and resources within and outside of organizations. Distance education is the third key component of entrepreneurial career development. Today, distance-delivered courses and programs create new educational opportunities that women and men can use to invest in their human and social capital as well as their potential. This paper presents the three keys to entrepreneurial career development along with evidence that supports the increasing importance for women to enhance their career success by embracing entrepreneurial strategies designed to leverage the connections among human capital, social capital, and distance education
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