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Coramin is a package that provides tools for developing tailored algorithms for mixed-integer nonlinear programming problems. This software includes the ability to: - Generate convex or piecewise relaxations of nonlinear optimization problems, addressing bilinear, quadratic, and convex/concave univariate functions - Perform optimization-based bounds tightening on all or subsets of the problem variables - Generate polyhedral envelopes for multi-linear functions
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  • Software/Code
The Compadre Toolkit solves a minimization problem, that once solved allows a user to reconstruct a function from sample data collected from a cloud of data sites. The solution to this minimization can also be used to assemble a linear system that can be solved numerically using some other software. The minimization problem the toolkit solves is to find the optimal finite polynomial in a user specified finite dimensional space with regards to minimizing an objective function which measures a linear sampling functional applied to the polynomial, compared to the same sampling functional applied to the source function, weighted by a positive kernel that has compact support.
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  • Software/Code
This program a new physical insight regarding efforts to evaluate electrochemical catalysts being developed for electrochemical energy conversion and storage. In particular, we ask: The methodology described here offers a solution to the problem of how to conduct Tafel analysis, which is used in determining electrocatalyst performance, in a quantitative manner, rather than through the qualitative guesswork it currently requires. This enables the measurement of electrocatalyst Tafel slopes and their associated parameters in a way that avoids the introduction of researcher bias, a problem to which current methods of Tafel fitting are prone. This procedure should significantly improve the ability of researchers working in the field of electrochemical energy conversion to rate and compare the catalyst materials being developed, advancing the characterization toolkit available to experimental electrochemists. This work is born out of our general hypothesis that it should be possible to determine the proper regions for unambiguously fitting Tafel data by applying some set of physical constraints that link aspects of a Tafel plot to its corresponding J-V polarization curve. This algorithm applies such constraints and achieves the extraction of Tafel slopes in a wholly quantifiable and reliable fashion. Verification of this approach is achieved by pairing the theory with experiment, as the algorithm was tested using experimentally acquired data of three distinct, electrochemical reactions: platinum hydrogen evolution, iridium-catalyzed oxygen evolution, and platinum-catalyzed dioxygen reduction. For each of these cases, the algorithm predicts the same Tafel slope as those reported in long-established bodies of electrochemical literature, results suggesting the general applicability of this method for determining electrocatalyst Tafel slopes.
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The Advanced Terrestrial Simulator (formerly sometimes known as the Arctic Terrestrial Simulator) is a code for solving ecosystem-based, integrated, distributed hydrology. Capabilities are largely based on solving various forms of Richards equation coupled to a surface flow equation, along with the needed sources and sinks for ecosystem and climate models. This can (but need not) include thermal processes (especially ice for frozen soils), evapo-transpiration, albedo-driven surface energy balances, snow, biogeochemistry, plant dynamics, deformation, transport, and much more. Preferred citation (including correct author order): Ethan Coon, Markus Berndt, Ahmad Jan, Daniil Svyatsky, Adam Atchley, Eugene Kikinzon, Dylan Harp, Gianmarco Manzini, Eitan Shelef, Konstantin Lipnikov, Rao Garimella, Chonggang Xu, David Moulton, Satish Karra, Scott Painter, Elchin Jafarov, and Sergi Molins. 2019. Advanced Terrestrial Simulator. Next Generation Ecosystem Experiments Arctic Data Collection, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, USA. Version [xxx]. DOI link: https://doi.org/10.11578/dc.20190911.1
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Keras layers for end-to-end learning on molecular structure. Based on Keras, Tensorflow, and RDKit. Source code used in the study Message-passing neural networks for high-throughput polymer screening
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  • Software/Code
eZeeKonfigurator is a web application and supporting tools for configuring Zeek (formerly Bro) systems. Zeek is an open-source tool developed at LBNL that's used to secure computer networks. A recent version of Zeek introduced the configuration framework, where changes can be made while the system is running. However, the provided method is difficult to operationalize, as it requires a set of text files to be deployed and updated across all the Zeek systems. eZeeKonfigurator provides an easy-to-use web interface to this. Users can view and modify options in a web application, and then those changes are deployed to the desired Zeek systems. Additionally, users benefit from additional features, such as: * Logging and auditing, to determine who made what change and when * Automated expiration of changes (e.g. an exception is added for 2 weeks, after which time it will be removed) * Validation of changes and verification that the change has been applied * Fine-grained role-based access
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PTFREAD is an Excel Add-In used to post-process MELCOR plotfile data for plotting and animation of MELCOR results.
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Skybright is a utility to estimate the sky brightness in images of the sky taken by optical astronomical telescopes. It uses a simple three component model, including airglow, scattered moonlight, and twilight. The code is derived from an extraction of the sky estimation code in obstac, the telescope scheduling code used by the Dark Energy Survey (written by the same author).
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  • Software/Code
This software uses averaged weighted estimators to classify instances and then explicate the individual decision process in classification. The software has state of the art performance in accuracy, while maintaining full explainability. It does this by calculating hierarchically averaged probabilities for a large class of feature combinations and updating them ‘on-the-fly’. On the fly updating also allows the model to be accurate, relative to the total dataset, maintaining accuracy in real-time, without a need to retrain the classifier.
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  • Software/Code
Brief Description for Public Release: A collection of general code samples demonstrating issues encountered with using OpenMP4.5 (and some CUDA) during efforts to port codes to a GPU platform using IBM XL. These independent examples include both C++ and FORTRAN language usage, along with attempts to use OpenMP and CUDA in an interoperable manner. This suite of code samples is meant to supplement the examples provided by openmp.org at https://github.com/OpenMP/Examples, especially in regards to FORTRAN language support and OpenMP/CUDA interoperability.
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  • Software/Code
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