24,754 research outputs found
RETURNS TO SCHOOLING: SKILLS ACCUMULATION OR INFORMATION REVELATION?
This paper explores the degree to which imperfect information in the labour market regarding worker quality is likely to impact employment opportunities, as well as the wages associated with those opportunities. The primary purpose of this paper is to provide preliminary empirical evidence that market imperfections exist in South Africa's labour market, that those imperfections could be based on asymmetric private information, and that market participants pursue information gathering and revelation strategies to help mitigate the negative effects of the information asymmetries.Information asymmetry, signalling, screening, returns education
Tunable magnetization damping in transition metal ternary alloys
We show that magnetization damping in Permalloy, Ni80Fe20 (``Py''), can be
enhanced sufficiently to reduce post-switching magnetization precession to an
acceptable level by alloying with the transition metal osmium (Os). The damping
increases monotonically upon raising the Os-concentration in Py, at least up to
9% of Os. Other effects of alloying with Os are suppression of magnetization
and enhancement of in-plane anisotropy. Magnetization damping also increases
significantly upon alloying with the five other transition metals included in
this study (4d-elements: Nb, Ru, Rh; 5d-elements: Ta, Pt) but never as strongly
as with Os.Comment: 4 pages, submitted to Appl. Phys. Let
Development of techniques to improve bladder materials and test methods Final report, May 18, 1966 - May 17, 1968
Process parameters for fabricating flexible Teflon films, crystallinity determinations, and techniques for electroplating Teflon films with lea
Polymers for spacecraft hardware Monthly technical progress report, 10 Feb. 1967 - 1 Mar. 1967
Test program for polymeric products with spacecraft application
A Renormalization Group for Hamiltonians: Numerical Results
We describe a renormalization group transformation that is related to the
breakup of golden invariant tori in Hamiltonian systems with two degrees of
freedom. This transformation applies to a large class of Hamiltonians, is
conceptually simple, and allows for accurate numerical computations. In a
numerical implementation, we find a nontrivial fixed point and determine the
corresponding critical index and scaling. Our computed values for various
universal constants are in good agreement with existing data for
area-preserving maps. We also discuss the flow associated with the nontrivial
fixed point.Comment: 11 Pages, 2 Figures. For future updates, check
ftp://ftp.ma.utexas.edu/pub/papers/koch
Merger of Black Holes in the Galactic Center
We present the results of three body simulations focused on understanding the
fates of intermediate mass black holes (IBH) that drift within the central 0.5
pc of the Galaxy. In particular, we modeled the interactions between pairs of
black holes as they orbit a central blac k hole of mass
. The simulations performed assume a
Schwarzschild geometry and account for Chandrasekhar dynamical friction as well
as acceleration resulting from energy lost due to gravitational radiation.
We found the branching ratio for one of the orbiting IBHs to merge with the
CBH was 0.95 and is independent of the inner IBH's initial eccentricity as well
as the rate of sinking. This, coupled with an infall rate of yrs
for an IBH to drift into the Galactic center, results in an IBH-CBH merger
every Myrs. Lastly we found that the IBH-IBH-CBH triple body
system ``resets'' itself, in the sense that a system with an inner I BH with an
initially circular orbit generally left behind an IBH with a large
eccentricity, whereas a system in which the inner IBH had a high eccentricity
() usually left a remnant with low eccentricity. Branching ratios
for different outcomes are also similar in the two cases.Comment: Official paper to appear in November 2008 issue of Ap
On piezophase effects in mechanically loaded atomic scale Josephson junctions
The response of an intrinsic Josephson contact to externally applied stress
is considered within the framework of the dislocation-induced atomic scale
Josephson effect. The predicted quasi-periodic (Fraunhofer-like)stress-strain
and stress-current patterns should manifest themselves for experimentally
accessible values of applied stresses in intrinsically defected (e.g.,twinned)
crystals.Comment: REVTEX (epsf style), 2 EPS figure
A universal ionization threshold for strongly driven Rydberg states
We observe a universal ionization threshold for microwave driven one-electron
Rydberg states of H, Li, Na, and Rb, in an {\em ab initio} numerical treatment
without adjustable parameters. This sheds new light on old experimental data,
and widens the scene for Anderson localization in light matter interaction.Comment: 4 pages, 1 figur
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