11,248 research outputs found
Monte Carlo simulation by computer for life-cycle costing
Prediction of behavior and support requirements during the entire life cycle of a system enables accurate cost estimates by using the Monte Carlo simulation by computer. The system reduces the ultimate cost to the procuring agency because it takes into consideration the costs of initial procurement, operation, and maintenance
Determination of the zeta potential for highly charged colloidal suspensions
We compute the electrostatic potential at the surface, or zeta potential
, of a charged particle embedded in a colloidal suspension using a
hybrid mesoscopic model. We show that for weakly perturbing electric fields,
the value of obtained at steady state during electrophoresis is
statistically indistinguishable from in thermodynamic equilibrium. We
quantify the effect of counterions concentration on . We also evaluate
the relevance of the lattice resolution for the calculation of and
discuss how to identify the effective electrostatic radius.Comment: 8 pages, 3 figures with 2 panel
Research into the feasibility of metal- and oxide-film capacitors
Thin film capacitors with up to twenty-two active layers have been deposited by RF sputtering. The materials were aluminum electrodes of 1200 to 1500 angstrom thickness and silica dielectric layers of 3000 to 6000 angstrom thickness. The best electrical characteristics were capacitances of nearly 0.1 microfarad for an active area of 1.25 square centimeters, dissipation factor of less than 0.01 over a frequency range of 0.5 to 100 kilohertz and energy density of approximately 70 millijoules per cubic centimeter of active deposited material at a working voltage of 40 volts. These aluminum-silica capacitors exhibit excellent electrical stability over a temperature range from -55 C to +300 C
THE POTENTIAL FOR FINANCIAL SAVINGS IN RURAL MOZAMBICAN HOUSEHOLDS
Many policy makers and businesses erroneously believe that rural populations, particularly in Africa, have no margin for savings over consumption needs. This study examines the potential for financial savings in rural Mozambican households by looking at the determinants of savings behavior. An econometric model for a household's saving behavior was estimated using data from 113 rural households from Nampula province in Mozambique. Results indicate that income, physical wealth, household size, and years of schooling affect a household's savings behavior. The study also finds that Mozambican rural households use their own grassroots associations for many financial services due to the lack of access to formal financial intermediaries.Consumer/Household Economics, Financial Economics,
Information requirements for guidance and control systems
Control or guidance system performance dependency on information handling by subsystem
Star Formation Histories of Nearby Elliptical Galaxies. II. Merger Remnant Sample
This work presents high spectroscopic observations of a sample of six
suspected merger remnants, selected primarily on the basis of H{\sc i} tidal
debris detections. Single stellar population analysis of these galaxies
indicates that their ages, metallicities, and -enhancement ratios are
consistent with those of a representative sample of nearby elliptical galaxies.
The expected stellar population of a recent merger remnant, young age combined
with low [/Fe], is not seen in any H{\sc i}-selected galaxy. However,
one galaxy (NGC~2534), is found to deviate from the -plane in the sense
expected for a merger remnant. Another galaxy (NGC~7332), selected by other
criteria, best matches the merger remnant expectations.Comment: 12 pages, 10 figures, accepted by A
Faraday waves on a viscoelastic liquid
We investigate Faraday waves on a viscoelastic liquid. Onset measurements and
a nonlinear phase diagram for the selected patterns are presented. By virtue of
the elasticity of the material a surface resonance synchronous to the external
drive competes with the usual subharmonic Faraday instability. Close to the
bicriticality the nonlinear wave interaction gives rise to a variety of novel
surface states: Localised patches of hexagons, hexagonal superlattices,
coexistence of hexagons and lines. Theoretical stability calculations and
qualitative resonance arguments support the experimental observations.Comment: 4 pages, 4figure
Rabi oscillations in a quantum dot-cavity system coupled to a non-zero temperature phonon bath
We study a quantum dot strongly coupled to a single high-finesse optical
microcavity mode. We use a rotating wave approximation method, commonly used in
ion-laser interactions, tegether with the Lamb-Dicke approximation to obtain an
analytic solution of this problem. The decay of Rabi oscillations because of
the electron-phonon coupling are studied at arbitrary temperature and
analytical expressions for the collapse and revival times are presented.
Analyses without the rotating wave approximation are presented by means of
investigating the energy spectrum.Comment: 7 pages, 5 figures; Revised versio
Design of Nonstructural Members in Accordance with AISI S220
AISI S220, the North American Standard for Cold-Formed Steel Framing - Nonstructural Members, was developed in 2011 to help clearly delineate and eliminate confusion between the requirements for cold-formed steel structural members and nonstructural members. This paper is intended as an introduction to this standard and as an illustrative guide for applying the provisions to the design of nonstructural members
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