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

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

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

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

Tango Glide

[Verse 1] Little Nancy Green and handsome Harry Brown, Could be found at ev’ry Tango ball in town, They were there from start until the ve’ry end They had ‘evry twist and bend First they’d make a bow and skip the double twirl, Then they’d Tango round and then another whirl, And when the orchestra began to play Nancy Green would softly say: [Chorus] Oh won’t 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 play’s I can hardly stand, Play it your best don’t dare to rest. Oh, it’s tantalizing, It’s 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 “let us twirl some more” All the other couples would keep watching her step, Whit this murmur on their lips “We’ll get that yet,” 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

Understanding the dynamics of photoionization-induced solitons in gas-filled hollow-core photonic crystal fibers

We present in detail our developed model [Saleh et al., Phys. Rev. Lett. 107] that governs pulse propagation in hollow-core photonic crystal fibers filled by an ionizing gas. By using perturbative methods, we find that the photoionization process induces the opposite phenomenon of the well-known Raman self-frequency red-shift of solitons in solid-core glass fibers, as was recently experimentally demonstrated [Hoelzer et al., Phys. Rev. Lett. 107]. This process is only limited by ionization losses, and leads to a constant acceleration of solitons in the time domain with a continuous blue-shift in the frequency domain. By applying the Gagnon-B\'{e}langer gauge transformation, multi-peak `inverted gravity-like' solitary waves are predicted. We also demonstrate that the pulse dynamics shows the ejection of solitons during propagation in such fibers, analogous to what happens in conventional solid-core fibers. Moreover, unconventional long-range non-local interactions between temporally distant solitons, unique of gas plasma systems, are predicted and studied. Finally, the effects of higher-order dispersion coefficients and the shock operator on the pulse dynamics are investigated, showing that the resonant radiation in the UV [Joly et al., Phys. Rev. Lett. 106] can be improved via plasma formation.Comment: 9 pages, 10 figure

Anti-microbial Use in Animals: How to Assess the Trade-offs

Antimicrobials are widely used in preventive and curative medicine in animals. Benefits from curative use are clear – it allows sick animals to be healthy with a gain in human welfare. The case for preventive use of antimicrobials is less clear cut with debates on the value of antimicrobials as growth promoters in the intensive livestock industries. The possible benefits from the use of antimicrobials need to be balanced against their cost and the increased risk of emergence of resistance due to their use in animals. The study examines the importance of animals in society and how the role and management of animals is changing including the use of antimicrobials. It proposes an economic framework to assess the trade-offs of anti-microbial use and examines the current level of data collection and analysis of these trade-offs. An exploratory review identifies a number of weaknesses. Rarely are we consistent in the frameworks applied to the economic assessment anti-microbial use in animals, which may well be due to gaps in data or the prejudices of the analysts. There is a need for more careful data collection that would allow information on (i) which species and production systems antimicrobials are used in, (ii) what active substance of antimicrobials and the application method and (iii) what dosage rates. The species need to include companion animals as well as the farmed animals as it is still not known how important direct versus indirect spread of resistance to humans is. In addition, research is needed on pricing antimicrobials used in animals to ensure that prices reflect production and marketing costs, the fixed costs of anti-microbial development and the externalities of resistance emergence. Overall, much work is needed to provide greater guidance to policy, and such work should be informed by rigorous data collection and analysis systems

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