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At least 1,495 records · Page 83

Go/No-Go Decision Point 1 Report

To satisfy the G/NG point 1 we have employed GEOS hydraulic fracturing module to simulate one of the Diagnostic Fracture Injection Tests conducted at well 58-32. The hydraulic fracturing solver relies on a finite element discretization of the mechanics fully coupled to a finite volume discretization of the fluid flow. Fractures are explicitly modeled as lower dimensional manifolds and discretized by 2D elements sitting at the boundary of cell elements. We have calibrated our model to reproduce the DFIT corresponding to Zone 2 Cycle 4 of the injection tests that took place at well 58-32.

15 GEOTHERMAL ENERGY↗

Legal and Regulatory Status of Abandoned Mine Methane in Selected Countries: Considerations for Decision Makers

Methane, a greenhouse gas 21 times more potent than carbon dioxide, is a major contributor to global emissions of greenhouse gases. Globally, the coal mining industry accounts for 8% of total methane emissions. Coal mines capture methane mostly for safety reasons because methane can be dangerous for underground mining. However, after closure, underground coal mines continue to release methane into the atmosphere. This methane is known as Abandoned Mine Methane (AMM). Several countries have successfully developed an enabling environment that encourages AMM recovery and utilization. The experiences of Germany, the United Kingdom, Australia, and the United States can provide valuable lessons for other countries wishing to utilize the potential of AMM. The example of these countries shows that a proper legal and regulatory framework can facilitate utilization of methane from abandoned coal mines for the natural gas market, power generation, and development of combined heat and power.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Fossil Fuel Transitions Framework: Case studies of the decision-making process for energy and economic development pathways

The Net Zero World Initiative leverages expertise across U.S. government agencies and the U.S. Department of Energy’s (DOE) national laboratories, in partnership with other governments and philanthropies, to accelerate the decarbonization of global energy systems. This whole-of-government approach supports countries committed to raising their climate ambitions by co-creating and implementing highly tailored, actionable technical and investment strategies that put just and sustainable net-zero solutions within reach. The Net Zero World Initiative enables country partners to harness the convening power and technical expertise of U.S. and international industry, think tanks, and technical institutions.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Assessing the Value of Seismic Amplitude Versus Offset (AVO) Attributes for CO2 Storage Project Using a Bayesian Network Model for Decision Support

Attributes versus offset (AVO) are a set of measurements to analyze how the characteristics of reflected seismic waves change as a function of the offset. It can be useful for monitoring CO2 storage sites because the presence of leaked CO2 into the overlying aquifer can change the properties of the rocks and pore fluids composition that can alter the way seismic waves reflect and their amplitudes. The time-lapse changes in AVO attributes derived from repeat seismic surveys can help identify anomalies or shifts in the subsurface that could potentially be used as an indicator for CO2 leak detection. Our study leverages multiple seismic attributes derived from synthetic seismic data and Bayesian network model to quantify the probability of leak detection in the overlying aquifer above the storage reservoir. It helps to quantify the value of individual seismic attributes at multiple monitoring periods based upon their sensitivities.

Kumar, Abhash↗

The Screening Tool for Industrial Resilience: Risk-Informed Decision Making to Support Resilience Planning

The Screening Tool for Industrial Resilience (STIR) helps small and medium-sized manufacturing plants manage risk to their production. Developed by the Pacific Northwest National Laboratory under direction and funding from the Department of Energy’s Office of Manufacturing and Energy Supply Chains, the STIR helps manufacturers enhance their resilience to a variety of disruptive events, both natural and human-caused, that could interrupt normal operations. This report provides an overview of the STIR’s risk-informed, high-level approach to resilience planning, which identifies potential solutions that could enhance site resilience based on calculated major risk drivers.

97 MATHEMATICS AND COMPUTING↗

Towards AI Based Data Classification for Decision Making During Testing

During the development of high-consequence items, test systems should be capable of differentiating between test failures resulting from narrowly missing requirements versus those indicating potentially catastrophic faults. In many instances, classifying the data corresponds to simply identifying whether measured waveforms have approximately the anticipated shape. Cast in this light, the problem reduces to converting raw data into a form optimal for use with neural network classifiers. This manuscript investigates different means of representing raw data for image classification. Raw data plots and Short Time Fourier Transform (STFT) spectrograms are classified by both custom built, small-scale, Convolution Neural Networks (CNN) and open-source, multi-million parameter, pre-trained deep CNNs. In the case of time varying frequency content, the STFTs provide images with greater detail and can be accurately classified with simpler networks. This requires less memory and runs faster than classifying the raw data using the more sophisticated options—making STFTs optimal for applications with memory constraints. STFTs are not a panacea. In some cases the time-domain signal contains useful information that should not be discarded. Rather than using raw data or STFTs, the images can be constructed from both by using red and green channels of an RGB image to visualize the real and imaginary components of the transform, with the raw data occupying the blue channel.

97 MATHEMATICS AND COMPUTING↗

Decision and Control of Complex Systems – A Data-Drive Framework

During the project period, we have collaborated with other team members and developed novel algorithms for novelty detection, continual learning, and graph learning algorithms for dynamic systems. The results are documented in publications and meeting notes. Moreover, we leverage virtual collaboration tools (such as Basecamp, Microsoft Teams and Zoom) for technical exchanges. Our research on novelty detection was published at AAAI 2022 and Lecture Notes in Artificial Intelligence, Springer Nature. The newly developed algorithms were successfully applied to realistic cases, including thermal data from buildings at Pacific Northwest National Lab and microelectronic data provided by GlobalFoundries. Multiple publications have been produced from this project, in collaboration with other team members. Three PhD students were supported in this project to conduct their research.

42 ENGINEERING↗