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Huang, Andy

Publications and source records attributed to Huang, Andy.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Robustness and Validation of Model and Digital Twins Deployment

For digital twins (DTs) to become a central fixture in mission critical systems, a better understanding is required of potential modes of failure, quantification of uncertainty, and the ability to explain a model’s behavior. These aspects are particularly important as the performance of a digital twin will evolve during model development and deployment for real-world operations.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2020

Prediction of Circuit Response to an Electromagnetic Environment (ASC IC FY2020 Milestone 7179)

This report covers the work performed in support of the ASC Integrated Codes FY20 Milestone 7179. For the Milestone, Sandia's Xyce analog circuit simulator was enhanced to enable a loose coupling to Sandia's EIGER electromagnetic (EM) simulation tool. A device was added to Xyce that takes as its input network parameters (representing the impedance response) and short-circuit current induced in a wire or other element, as calculated by an EM simulator such as EIGER. Simulations were performed in EIGER and in Xyce (using Harmonic Balance analysis) for a variety of linear and nonlinear circuit problems, including various op amp circuits. Results of those simulations are presented and future work is also discussed.

42 ENGINEERING↗
DOE OSTI2020

Charon User Manual (V.2.1) (Rev.01)

This manual gives usage information for the Charon semiconductor device simulator. Charon was developed to meet the modeling needs of Sandia National Laboratories and to improve on the capabilities of the commercial TCAD simulators; in particular, the additional capabilities are running very large simulations on parallel computers and modeling displacement damage and other radiation effects in significant detail. The parallel capabilities are based around the MPI interface which allows the code to be ported to a large number of parallel systems, including linux clusters and proprietary "big iron" systems found at the national laboratories and in large industrial settings.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2020

Gemma

Gemma is a linear electromagnetic code developed at Sandia National Laboratories based on the method of moments in the frequency domain, with the objective of supporting next-generation high-performance computing (HPC) platforms. Gemma provides full-wave computational electromagnetic modeling. As an example, Gemma models electromagnetic radiation (EMR) environments, including those resulting from radar (both hostile and friendly) and high-power-electromagnetic (HPEM) sources. Gemma refers to a suite of source code and scripts that aid in compiling, running, and testing the primary Gemma executable, which can be compiled for diverse platforms including CPUs, GPUs, and MICs by leveraging Sandia's Kokkos library.SAND2019-15221 M Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

Zinser, Brian↗
DOE OSTI2019

Analytic band-to-trap tunneling model including band offset for heterojunction devices

In this paper, we present an analytic band-to-trap tunneling model based on the open boundary scattering approach. The new model has three major advantages: (i) It includes not only the well-known electric field effect, but more importantly, the effect of heterojunction band offset. This feature allows us to simulate both electric field and band offset enhanced carrier recombination near a heterojunction in heterostructures. (ii) Its analytic form enables straightforward implementation into a parallel Technology Computer Aided Design device and circuit simulators. (iii) The developed method can be used for any potentials which can be approximated to a good degree such that the Schrödinger equation with open boundary conditions results in piecewise analytic wave functions. Simulation results of an InGaP/GaAs heterojunction bipolar transistor (HBT) reveal that the proposed model predicts significantly increased base currents, because the tunneling of holes in the base to traps in the emitter is greatly enhanced by the emitter-base band offset. Lastly, this finding, which is not captured by existing band-to-trap tunneling models, is consistent with the experimental observation for an InGaP/GaAs HBT after neutron irradiation.

36 MATERIALS SCIENCE↗