3,225 research outputs found
Investigation of new concepts of adaptive devices Quarterly technical report, 3 Dec. 1968 - 2 Mar. 1969
Conduction mechanisms and transient behavior of memory device using semiconductor device
An investigation of the effects of radiation on silicon nitride insulated gate /MNS/ transistors Final report
Radiation effects on silicon nitride insulated gate field effect transistor
Investigation of new concepts of adaptive devices Quarterly technical report, 3 Mar. - 2 Jun. 1969
Charge decay processes in memory device and in new metal nitride semiconductor light-sensitive memory elemen
Estimating Multiattribute Spatial Choice Models
In this paper, an interactive computer program for estimating the parameters of spatial choice models with multiattribute utilities is presented. The models to be calibrated may be unconstrained, singly constrained, or doubly constrained random utility choice or entropy-maximizing interaction models. Utilities may be associated with choice alternatives (zones) or with the choices themselves (trips). The program maximizes the likelihood of the choice matrix (trip table) given observed choices (trips) using a combination of gradient search and Newton-Raphson iteration methods.
The paper contains a specification of the range of models that can be calibrated with the program and a description of its solution algorithm and organization, as well as an illustrative application and a listing of the source code
Tango Glide
[Verse 1]
Little Nancy Green and handsome Harry Brown, Could be found at evâry Tango ball in town, They were there from start until the veâry end They had âevry twist and bend First theyâd make a bow and skip the double twirl, Then theyâd Tango round and then another whirl, And when the orchestra began to play Nancy Green would softly say:
[Chorus]
Oh wonât you please play that Tango glide, That very name Tango makes my feet slide, I want to twirl, I want to whirl, Oh it is a daisy, Gee, it sets me crazy. Oh! Oh! That music is simply grand. When it is playâs I can hardly stand, Play it your best donât dare to rest. Oh, itâs tantalizing, Itâs just hypnotizing, When we do that Tango Glide.
[Verse 2]
When it comes to dancing that great Tango Dance, Take a tip from me and leave the rest to Nance, She would glide across that waxed and polished floor. Saying âlet us twirl some moreâ All the other couples would keep watching her step, Whit this murmur on their lips âWeâll get that yet,â And all those dancers present at the ball They would yell now one and all:
[Chorus
Numerical Investigation of Light Scattering off Split-Ring Resonators
Recently, split ring-resonators (SRR's) have been realized experimentally in
the near infrared (NIR) and optical regime. In this contribution we numerically
investigate light propagation through an array of metallic SRR's in the NIR and
optical regime and compare our results to experimental results.
We find numerical solutions to the time-harmonic Maxwell's equations by using
advanced finite-element-methods (FEM). The geometry of the problem is
discretized with unstructured tetrahedral meshes. Higher order, vectorial
elements (edge elements) are used as ansatz functions. Transparent boundary
conditions and periodic boundary conditions are implemented, which allow to
treat light scattering problems off periodic structures.
This simulation tool enables us to obtain transmission and reflection spectra
of plane waves which are incident onto the SRR array under arbitrary angles of
incidence, with arbitrary polarization, and with arbitrary
wavelength-dependencies of the permittivity tensor. We compare the computed
spectra to experimental results and investigate resonances of the system.Comment: 9 pages, 8 figures (see original publication for images with a better
resolution
Magnetic metamaterials at telecommunication and visible frequencies
Arrays of gold split-rings with 50-nm minimum feature size and with an LC
resonance at 200-THz frequency (1500-nm wavelength) are fabricated. For normal
incidence conditions, they exhibit a pronounced fundamental magnetic mode,
arising from a coupling via the electric component of the incident light. For
oblique incidence, a coupling via the magnetic component is demonstrated as
well. Moreover, we identify a novel higher-order magnetic resonance at around
370 THz (800-nm wavelength) that evolves out of the Mie resonance for oblique
incidence. Comparison with theory delivers good agreement and also shows that
the structures allow for a negative magnetic permeability.Comment: 4 pages, 3 figure
Intercomparison of Hantzsch and fiber-laser-induced-fluorescence formaldehyde measurements
Two gas-phase formaldehyde (HCHO) measurement techniques, a modified commercial wet-chemical instrument based on Hantzsch fluorimetry and a custom-built instrument based on fiber laser-induced fluorescence (FILIF), were deployed at the atmospheric simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) to compare the instruments' performances under a range of conditions. Thermolysis of para-HCHO and ozonolysis of 1-butene were used as HCHO sources, allowing for calculations of theoretical HCHO mixing ratios. Calculated HCHO mixing ratios are compared to measurements, and the two measurements are also compared. Experiments were repeated under dry and humid conditions (RH 60%) to investigate the possibility of a water artifact in the FILIF measurements. The ozonolysis of 1-butene also allowed for the investigation of an ozone artifact seen in some Hantzsch measurements in previous intercomparisons. Results show that under all conditions the two techniques are well correlated (R2 â„ 0.997), and linear regression statistics show measurements agree with within stated uncertainty (15% FILIF + 5% Hantzsch). No water or ozone artifacts are identified. While a slight curvature is observed in some Hantzsch vs. FILIF regressions, the potential for variable instrument sensitivity cannot be attributed to a single instrument at this time. Measurements at low concentrations highlight the need for a secondary method for testing the purity of air used in instrument zeroing and the need for further FILIF White cell outgassing experiments
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