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What can simulation test beds teach us about social science? Results of the ground truth program

Computational and Mathematical Organization Theory

Naugle, Asmeret B.; Krofcheck, Daniel J.; Warrender, Christina E.; Lakkaraju, Kiran; Swiler, Laura P.; Verzi, Stephen J.; Emery, Benjamin; Murdock, Jaimie; Bernard, Michael; Romero, Vicente J.

The ground truth program used simulations as test beds for social science research methods. The simulations had known ground truth and were capable of producing large amounts of data. This allowed research teams to run experiments and ask questions of these simulations similar to social scientists studying real-world systems, and enabled robust evaluation of their causal inference, prediction, and prescription capabilities. We tested three hypotheses about research effectiveness using data from the ground truth program, specifically looking at the influence of complexity, causal understanding, and data collection on performance. We found some evidence that system complexity and causal understanding influenced research performance, but no evidence that data availability contributed. The ground truth program may be the first robust coupling of simulation test beds with an experimental framework capable of teasing out factors that determine the success of social science research.

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Data Science and Machine Learning for Genome Security

Verzi, Stephen J.; Krishnakumar, Raga; Levin, Drew; Krofcheck, Daniel J.; Williams, Kelly P.

This report describes research conducted to use data science and machine learning methods to distinguish targeted genome editing versus natural mutation and sequencer machine noise. Genome editing capabilities have been around for more than 20 years, and the efficiencies of these techniques has improved dramatically in the last 5+ years, notably with the rise of CRISPR-Cas technology. Whether or not a specific genome has been the target of an edit is concern for U.S. national security. The research detailed in this report provides first steps to address this concern. A large amount of data is necessary in our research, thus we invested considerable time collecting and processing it. We use an ensemble of decision tree and deep neural network machine learning methods as well as anomaly detection to detect genome edits given either whole exome or genome DNA reads. The edit detection results we obtained with our algorithms tested against samples held out during training of our methods are significantly better than random guessing, achieving high F1 and recall scores as well as with precision overall.

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Synthetic threat injection using digital twin informed augmentation

Proceedings of SPIE - The International Society for Optical Engineering

Krofcheck, Daniel J.; John, Esther W.L.; Galloway, Hugh; Sorensen, Asael H.; Jameson, Carter D.; Aubry, Connor; Prasadan, Arvind; Forrest, Robert

The growing x-ray detection burden for vehicles at Ports of Entry in the US requires the development of efficient and reliable algorithms to assist human operator in detecting contraband. Developing algorithms for large-scale non-intrusive inspection (NII) that both meet operational performance requirements and are extensible for use in an evolving environment requires large volumes and varieties of training data, yet collecting and labeling data for these enivornments is prohibitively costly and time consuming. Given these, generating synthetic data to augment algorithm training has been a focus of recent research. Here we discuss the use of synthetic imagery in an object detection framework, and describe a simulation based approach to determining domain-informed threat image projection (TIP) augmentation.

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A Framework to Model and Analyze Electric Grid Cascading Failures to Identify Critical Nodes

2022 17th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2022

Pierre, Brian J.; Krofcheck, Daniel J.; Munoz-Ramos, Karina; Arguello, Bryan

The goal of this work is to identify critical nodes in a bulk electric system for grid resilience to a specified threat. We present a cascading outage framework and an analytical framework for identifying electric grid failure trends and critical components. We create thousands of threat scenarios to be modeled in a dynamic electric grid cascading outage model. Each threat scenario determines which major grid components are removed from service due to the threat. The cascading outage model runs transient dynamic simulations which allow for secondary transients to affect the relays/protection leading to cascading outages. The results of the cascading model feed an analytics model to identify trends and critical components whose failure is more likely to cause serious systemic effects. Information on which system components are most critical to electric grid resilience can significantly assist grid planning and reduce grid consequences of large-scale disasters.

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Resilient adjudication in non-intrusive inspection with hierarchical object and anomaly detection

Proceedings of SPIE - The International Society for Optical Engineering

Krofcheck, Daniel J.; John, Esther W.L.; Galloway, Hugh; Sorensen, Asael H.; Jameson, Carter D.; Aubry, Connor; Prasadan, Arvind; Galasso, Jennifer; Goodman, Eric; Forrest, Robert

Large scale non-intrusive inspection (NII) of commercial vehicles is being adopted in the U.S. at a pace and scale that will result in a commensurate growth in adjudication burdens at land ports of entry. The use of computer vision and machine learning models to augment human operator capabilities is critical in this sector to ensure the flow of commerce and to maintain efficient and reliable security operations. The development of models for this scale and speed requires novel approaches to object detection and novel adjudication pipelines. Here we propose a notional combination of existing object detection tools using a novel ensembling framework to demonstrate the potential for hierarchical and recursive operations. Further, we explore the combination of object detection with image similarity as an adjacent capability to provide post-hoc oversight to the detection framework. The experiments described herein, while notional and intended for illustrative purposes, demonstrate that the judicious combination of diverse algorithms can result in a resilient workflow for the NII environment.

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Results 1–25 of 32
Results 1–25 of 32