5,901 research outputs found
Monolithically Patterned Wide-Narrow-Wide All-Graphene Devices
We investigate theoretically the performance advantages of all-graphene
nanoribbon field-effect transistors (GNRFETs) whose channel and source/drain
(contact) regions are patterned monolithically from a two-dimensional single
sheet of graphene. In our simulated devices, the source/drain and interconnect
regions are composed of wide graphene nanoribbon (GNR) sections that are
semimetallic, while the channel regions consist of narrow GNR sections that
open semiconducting bandgaps. Our simulation employs a fully atomistic model of
the device, contact and interfacial regions using tight-binding theory. The
electronic structures are coupled with a self-consistent three-dimensional
Poisson's equation to capture the nontrivial contact electrostatics, along with
a quantum kinetic formulation of transport based on non-equilibrium Green's
functions (NEGF). Although we only consider a specific device geometry, our
results establish several general performance advantages of such monolithic
devices (besides those related to fabrication and patterning), namely the
improved electrostatics, suppressed short-channel effects, and Ohmic contacts
at the narrow-to-wide interfaces.Comment: 9 pages, 11 figures, 2 table
Federal Subsidy for Laid-Off Workers' Health Insurance: A First Year's Report Card for the New COBRA Premium Assistance
Analyzes how the subsidy for laid-off workers' costs to continue their health coverage, included in the 2009 stimulus bill, affected enrollment. Considers determining factors, implications of health reform for extending the subsidy, and lessons learned
COBRA Subsidies for Laid-Off Workers: An Initial Report Card
Reviews the implementation of the government subsidy of COBRA health insurance premiums for laid-off workers in the 2009 stimulus package and its effects on COBRA enrollment and medical spending. Considers policy implications for access and affordability
Design of a fast computer-based partial discharge diagnostic system
Partial discharges cause progressive deterioration of insulating materials working in high voltage conditions and may lead ultimately to insulator failure. Experimental findings indicate that deterioration increases with the number of discharges and is consequently proportional to the magnitude and frequency of the applied voltage. In order to obtain a better understanding of the mechanisms of deterioration produced by partial discharges, instrumentation capable of individual pulse resolution is required. A new computer-based partial discharge detection system was designed and constructed to conduct long duration tests on sample capacitors. This system is capable of recording large number of pulses without dead time and producing valuable information related to amplitude, polarity, and charge content of the discharges. The operation of the system is automatic and no human supervision is required during the testing stage. Ceramic capacitors were tested at high voltage in long duration tests. The obtained results indicated that the charge content of partial discharges shift towards high levels of charge as the level of deterioration in the capacitor increases
Quantum measure and integration theory
This article begins with a review of quantum measure spaces. Quantum forms
and indefinite inner-product spaces are then discussed. The main part of the
paper introduces a quantum integral and derives some of its properties. The
quantum integral's form for simple functions is characterized and it is shown
that the quantum integral generalizes the Lebesgue integral. A bounded,
monotone convergence theorem for quantum integrals is obtained and it is shown
that a Radon-Nikodym type theorem does not hold for quantum measures. As an
example, a quantum-Lebesgue integral on the real line is considered.Comment: 28 page
Staying power : pastoral tenure in church planting
https://place.asburyseminary.edu/ecommonsatsdissertations/1594/thumbnail.jp
Dimensional Crossover of Dilute Neon inside Infinitely Long Single-Walled Carbon Nanotubes Viewed from Specific Heats
A simple formula for coordinates of carbon atoms in a unit cell of a
single-walled nanotube (SWNT) is presented and the potential of neon (Ne)
inside an infinitely long SWNT is analytically derived under the assumption of
pair-wise Lennard-Jones potential between Ne and carbon atoms. Specific heats
of dilute Ne inside infinitely long (5, 5), (10, 10), (15, 15) and (20, 20)
SWNT's are calculated at different temperatures. It is found that Ne inside
four kinds of nanotubes exhibits 3-dimensional (3D) gas behavior at high
temperature but different behaviors at low temperature: Ne inside (5, 5)
nanotube behaves as 1D gas but inside (10, 10), (15, 15), and (20, 20)
nanotubes behaves as 2D gas. Furthermore, at ultra low temperature, Ne inside
(5, 5) nanotube still displays 1D behavior but inside (10, 10), (15, 15), and
(20, 20) nanotubes behaves as lattice gas.Comment: 10 pages, 5 figure
Quasi-one dimensional fluids that exhibit higher dimensional behavior
Fluids confined within narrow channels exhibit a variety of phases and phase
transitions associated with their reduced dimensionality. In this review paper,
we illustrate the crossover from quasi-one dimensional to higher effective
dimensionality behavior of fluids adsorbed within different carbon nanotubes
geometries. In the single nanotube geometry, no phase transitions can occur at
finite temperature. Instead, we identify a crossover from a quasi-one
dimensional to a two dimensional behavior of the adsorbate. In bundles of
nanotubes, phase transitions at finite temperature arise from the transverse
coupling of interactions between channels.Comment: 8 pages, 5 figures, presented at CMT3
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