Optimal Matching in Julia Using Distributed Computing: Time Use Data (ATUS)

We have extended the multi-slice method of computating many-beam lattice images of perfect crystals to calculations for imperfect crystals using the artificial superlattice approach. Electron waves scattered from faulted regions of crystals are distributed continuously in reciprocal space, and all these waves interact dynamically with each other to give diffuse scattering patterns.In the computation, this continuous distribution can be sampled only at a finite number of regularly spaced points in reciprocal space, and thus finer sampling gives an improved approximation. The larger cell also allows us to defocus the objective lens further before adjacent defect images overlap, producing spurious computational Fourier images. However, smaller cells allow us to sample the direct space cell more finely; since the two-dimensional arrays in our program are limited to 128X128 and the sampling interval shoud be less than 1/2Å (and preferably only 1/4Å), superlattice sizes are limited to 40 to 60Å. Apart from finding a compromis superlattice cell size, computing time must be conserved.

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A New Numerical Model for Electron-Probe Analysis at High Depth Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016491x ◽

1996 ◽

Vol 54 ◽

pp. 490-491

Author(s):

P.-F. Staub ◽

C. Bonnelle ◽

F. Vergand ◽

P. Jonnard

Keyword(s):

Electron Probe ◽

Surface Segregation ◽

Depth Distribution ◽

Computing Time ◽

Depth Resolution ◽

Physical Parameters ◽

Electron Probe Analysis ◽

Interface Phases ◽

Excitation Conditions ◽

High Depth

Characterizing dimensionally and chemically nanometric structures such as surface segregation or interface phases can be performed efficiently using electron probe (EP) techniques at very low excitation conditions, i.e. using small incident energies (0.5<E0<5 keV) and low incident overvoltages (1<U0<1.7). In such extreme conditions, classical analytical EP models are generally pushed to their validity limits in terms of accuracy and physical consistency, and Monte-Carlo simulations are not convenient solutions as routine tools, because of their cost in computing time. In this context, we have developed an intermediate procedure, called IntriX, in which the ionization depth distributions Φ(ρz) are numerically reconstructed by integration of basic macroscopic physical parameters describing the electron beam/matter interaction, all of them being available under pre-established analytical forms. IntriX’s procedure consists in dividing the ionization depth distribution into three separate contributions:

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Age at Full-Time Use Predicts Language Outcomes Better Than Age of Surgery in Children Who Use Cochlear Implants

American Journal of Audiology ◽

10.1044/2019_aja-19-0073 ◽

2019 ◽

Vol 28 (4) ◽

pp. 986-992 ◽

Cited By ~ 2

Author(s):

Lisa R. Park ◽

Erika B. Gagnon ◽

Erin Thompson ◽

Kevin D. Brown

Keyword(s):

Cochlear Implants ◽

Time Use ◽

Expressive Language ◽

Normal Hearing ◽

Full Time ◽

Language Outcomes ◽

Age At Surgery ◽

Device Placement ◽

Device Use ◽

Better Than

Purpose The aims of this study were to (a) determine a metric for describing full-time use (FTU), (b) establish whether age at FTU in children with cochlear implants (CIs) predicts language at 3 years of age better than age at surgery, and (c) describe the extent of FTU and length of time it took to establish FTU in this population. Method This retrospective analysis examined receptive and expressive language outcomes at 3 years of age for 40 children with CIs. Multiple linear regression analyses were run with age at surgery and age at FTU as predictor variables. FTU definitions included 8 hr of device use and 80% of average waking hours for a typically developing child. Descriptive statistics were used to describe the establishment and degree of FTU. Results Although 8 hr of daily wear is typically considered FTU in the literature, the 80% hearing hours percentage metric accounts for more variability in outcomes. For both receptive and expressive language, age at FTU was found to be a better predictor of outcomes than age at surgery. It took an average of 17 months for children in this cohort to establish FTU, and only 52.5% reached this milestone by the time they were 3 years old. Conclusions Children with normal hearing can access spoken language whenever they are awake, and the amount of time young children are awake increases with age. A metric that incorporates the percentage of time that children with CIs have access to sound as compared to their same-aged peers with normal hearing accounts for more variability in outcomes than using an arbitrary number of hours. Although early FTU is not possible without surgery occurring at a young age, device placement does not guarantee use and does not predict language outcomes as well as age at FTU.

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