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Search Publications by: Zachary H. Levine (Fed)

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Displaying 51 - 75 of 296

Non-Uniqueness in Dual-Energy CT with Beam Hardening

September 13, 2017
Author(s)
Zachary H. Levine
Purpose: The goal is to determine whether dual-energy computed tomography (CT) leads to a unique reconstruction into two basis materials. Methods and Materials: The beam hardening equation is simplified to the single voxel case. The simplified equation is

Continuous-feed optical sorting of aerosol particles

June 15, 2016
Author(s)
John J. Curry, Zachary H. Levine
We consider the problem of sorting, by size, spherical particles of order 100 nm radius. The scheme we analyze consists of a heterogeneous stream of spherical particles flowing at an oblique angle across a Gaussian mode optical standing wave. Sorting is

Towards Estimating the Uncertainty Associated with 3D Geometry Reconstructions from Medical Image Data

May 23, 2016
Author(s)
Zachary H. Levine, Karim O. Genc, Stephen M. Luke, Todd Pietiela, Ross T. Cotton, Benjamin Ache, Phillipe G. Young, Marc Horner, Kevin C. Townsand
3D image based modeling for visualization, physics-based simulation or additive manufacturing, is becoming more common within R&D labs in academia, government and commercial industry. Computed Tomography (CT) is a common imaging modality used to obtain the

National Institute of Standards and Technology measurement service of the optical properties of biomedical phantoms: Current status

March 24, 2016
Author(s)
Paul Lemaillet, Catherine C. Cooksey, Zachary H. Levine, Adam L. Pintar, Jeeseong Hwang, David W. Allen
The National Institute for Standards and Technology (NIST) has maintained scales of reflectance and transmittance over several decades. Those scales are primarily intended for the regular transmittance, mirrors, and solid surface scattering diffusers. The

Adapting the Poisson-Influenced K-Means Algorithm for a Larger User Base

November 19, 2015
Author(s)
Brian P. Morris, Zachary H. Levine
A superconducting transition edge sensor (TES) can be a useful tool for counting the number of photons in a highly attenuated pulse of light, but it requires calibration for its outputs to be interpretable as photon numbers. The Poisson-Influenced K-Means

Absolute Calibration of a Variable Attenuator Using Few-Photon Pulses

June 12, 2015
Author(s)
Zachary H. Levine, Boris L. Glebov, Adam L. Pintar, Alan L. Migdall
We demonstrate the ability to calibrate a variable optical attenuator directly at the few photon level using a Superconducting Transition Edge Sensor (TES). Because of the inherent linearity of photon number resolving detection, no ex- ternal calibrations

Photon-number uncertainty in a superconducting transition-edge sensor beyond resolved-photon-number determination

September 10, 2014
Author(s)
Zachary H. Levine, Boris L. Glebov, Alan L. Migdall, Thomas Gerrits, Brice R. Calkins, Adriana E. Lita, Sae Woo Nam
As part of an effort to extend fundamental single-photon measurements into the macroscopic regime, we explore how best to assign photon-number uncertainties to output waveforms of a superconducting Transition Edge Sensor (TES) and how those assignments