SEARCH · Engineering Papers

Results for “task management”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,801 records · Page 100

All sources NASA NTRS DOE OSTI

DOE OSTI2018

Aluminum Clad Spent Nuclear Fuel Task 2: Oxide Layer Radiolytic Gas Generation Resolution Experiment Test Plan

This document presents the test plan for Task 2 of the Aluminum Clad Spent Nuclear Fuel Long Term Dry Storage Technical Issues Action Plan. This task’s overarching goal is the resolution of gas generation resulting from the radiolytic degradation of the oxide layers on aluminum. The uncertainty associated with the build-up of gaseous radiolytic products inside the ASNF storage canisters is one of the dominant technical challenges associated with long term dry storage of aluminum clad fuel. The objectives of the Task 2 test plan are to: 1. Understand how radiation chemistry inside the ASNF dry storage canister impacts extended dry storage performance. 2. Understand the radiation induced mechanisms governing the production of radiolytic gases and alteration of gas composition within a canister. 3. Correlate the observed changes in material properties of ASNF with the radiolytic degradation of aluminum oxide in fill environments of variable moisture and gas composition. 4. Compile a predictive kinetic modeling tool, to provide quantitative mechanistic insight into the in-cask radiation chemistry of ASNF. 5. Interface with the canister modeling activity of Task 3 to deliver degradation rates for package performance of both sealed and vented scenarios.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2013

Discovery of the First Leaking Double-Shell Tank - Hanford Tank 241-AY-102

Full text - Long Abstract. A routine video inspection of the annulus region of double-shell tank 241-A Y-102 in August of 2012 indicated the presence material in the annulus space between the primary and secondary liners. A comparison was made to previous inspections performed in 2006 and 2007. which indicated that a change had occurred. The material was observed at two locations on the floor of the annulus and one location at the top of the annulus region where the primary and secondary top knuckles meet (RPP-ASMT-53793). Subsequent inspections were performed. leading to additional material observed on the floor of the annulus space in a region that had not previously been inspected (WRPS-PER-2012-1363). The annulus Continuous Air Monitor (CAM) was still operational and was not indicating elevated radiation levels in the annulus region. When the camera from the inspections was recovered. it also did not indicate increased radiation above minimum contamination levels (WRPS-PER-2012-1363). A formal leak assessment team was established August 10, 2012 to review tank 241-AY-102 construction and operating histories and to determine whether the material observed in the annulus had resulted from a leak in the primary tank. The team consisted of individuals from Engineering. Base Operations and Environmental Protection. As this was a first-of-its-kind task. a method for obtaining a sample of the material in the annulus was needed. The consistency of the material was unknown.and the location of a majority of the material was not conducive to using the sampling devices that were currently available at Hanford. A subcontractor was tasked with the development fabrication.and testing of a sampling device that would be able to obtain multiple samples from the material on the annulus floor. as well as the material originating from a refractory air-slot near the floor of the annulus space. This sampler would need to be able to collect and dispense the material it collected into a sample jar retrieval device for transportation of the material to the 222-S laboratory on the Hanford site for analysis. The subcontractor agency fabricated a remote underground sampler by modifying off-the-shelf robotics and parts. Limited testing of the sampler was conducted using a mock-up of the tank annulus and one simulated material type -a salt block. The mock-up testing indicated that the sampler would be able to maneuver within the confined space and that the device worked with full functionality. A total of six weeks had passed from initiation to implementation of the new sampler in the 241-AY-102 tank annulus. Initial sample material was obtained from the annulus floor using the Off-Riser Sampler System that has been used at Hanford tor years to obtain material from the primary tanks. This could be used at the location near Riser 83 since the material was collected directly from the annulus floor and not from a location on the wall or behind a pipe, as was needed from the two locations near Riser 90. After obtaining a small sample of the material on the annulus floor.this sampler sustained terminal damage due to conduit pipes it had to transverse in order to collect and recover material from this location. Several issues were also encountered during deployment of the new sampler into the annulus near Riser 90. These included: Difficulty fitting the sampler down the 12-inch riser into the annulus due to a small tolerance in the size of the sampler; Failure of sampler components and functions during deployment including the camera. pneumatics.and bearing seals; Delays in the field due to supporting equipment issues including cables. cameras. and scaffolding; and, Low recovery of sample material obtained for analysis. The complications that occurred during deployment and use of the new sampler during the sampling event ultimately resulted in lower recovery of material from these locations in the annulus than was obtained using the Off-Riser Sampler System and limited the analyses that could be performed for determining the origin of the material. Following completion of the sample analyses and the assessment of its construction history and use. there was a consensus among the leak assessment team members that two of the three materials sampled from the annulus floor region were the result of waste leaking from a breach in the primary tank. The probable leak cause was identified as corrosion at high temperatures in a tank whose containment margins had been reduced due to construction difficulties (RPP-ASMT-53793). A formal Lessons Learned was created concerning designing equipment tor unique purposes under time constraints. This document was published in OPEXShare on May 20. 2013. It highlighted some of the issues that arose with the subcontractor sampler development and provided recommendations to prevent a recurrence should this task need to be performed again in the future. The document can be found at http://msa.hanford.gov/opex/lesson.cfm/2013/5/20/3481/AY-102-Annulus-Sampler-Designing-Equipment-for-Unique-Purposes-under-Time-Constraints/.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2024

Summary of Developing a Hanford Grout Modeling Framework Initial Workshop

The “Development of the Hanford Grout Modeling Framework” project as part of the Network of National Laboratories for Environmental Management and Stewardship (NNLEMS) funding program is underway. An initial project team workshop was held in Richland, WA on June 4 and 5, 2024 with participants from PNNL, SRNL, SNL, WRPS and CRESP (VU and UCF). The workshop covered an overview of the current state of the art in grout modeling tools provided by the team. Based on a focus on liquid waste immobilization grout and encapsulation grout for solid wastes and tank closure grout at Hanford, the team identified preliminary conceptual models for these three applications which will be used to form the basis of the Hanford Grout Modeling Framework. The key processes that can drive mechanisms impacting the grout performance were identified for each test case. The programmatic plan was also identified with five core Themes being selected that will form the focus of the project. Within each theme, individual tasks for Year 1 were planned in support of the development of an updated Hanford Grout Modeling Framework. This report presents a summary of the information presented during the workshop.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2023

Integrated End-to-end Performance Prediction and Diagnosis for Extreme Scientific Workflows

This report details recent progress for the ASCR funded project “Integrated End-to-end Performance Prediction and Diagnosis for Extreme Scientific Workflows”. We refer to the project as IPPD/2, reflecting the 2017 renewal under expanded scope and partners In IPPD/2, we increased our research scope to include data motion. We are focusing on three major aspects: a) observe how data is generated, distributed, and used; b) analyze how data is (repeatedly) consumed with a focus both on repeated patterns and anomalies; and c) explore how to optimize data motion. This new work on data motion will augment and complement IPPD/2’s research that focused on the computational aspects of tasks. We leverage and extend our existing tools and demonstrate our work on the Belle II workflow suite as well as on workflows from NSLS-II. The highlights of our work are as follows: Provenance for Workflows: Provenance is used to provide information enabling quality control, re-run computational workflows, and reproduce results. IPPD/2 has been building a scalable provenance management system that enables the capture of provenance from the high-level workflow through all relevant system levels in one integrated environment. Leveraging this work, our recent efforts have included using provenance as an enabling technique. Workload characterization: Leveraging provenance and analysis, we characterize data movement within network, storage, and memory over a variety of workloads. This characterization enables an understanding by performance analysts and application developers of the range of behaviors that could be expected. Performance Prediction for Workflows: The goal of modeling distributed workflows is to understand performance bottlenecks and enable more intelligent task scheduling to optimize selected metrics of interest (e.g., task throughput or output data rate). IPPD/2 has utilized both analytical and AI/ML modeling methodologies for performance modeling. Advanced Scheduling and Fault Modeling for Workflows: Scheduling of large-scale scientific workflows on geographically distributed resources is a challenging problem. To improve workflow throughput, we combined novel scheduling algorithms with task predictions from performance modeling and fault modeling. Dynamically Alleviating Bottlenecks in Workflows: Exploiting our provenance, analysis, and modeling efforts, we have explored and developed several techniques for dynamically detecting and alleviating bottlenecks in data movement. In particular, we have spent considerable effort demonstrating our techniques on production-like workflow configurations.

97 MATHEMATICS AND COMPUTING↗

NASA NTRS1992

A principled approach to the measurement of situation awareness in commercial aviation

The issue of how to support situation awareness among crews of modern commercial aircraft is becoming especially important with the introduction of automation in the form of sophisticated flight management computers and expert systems designed to assist the crew. In this paper, cognitive theories are discussed that have relevance for the definition and measurement of situation awareness. These theories suggest that comprehension of the flow of events is an active process that is limited by the modularity of attention and memory constraints, but can be enhanced by expert knowledge and strategies. Three implications of this perspective for assessing and improving situation awareness are considered: (1) Scenario variations are proposed that tax awareness by placing demands on attention; (2) Experimental tasks and probes are described for assessing the cognitive processes that underlie situation awareness; and (3) The use of computer-based human performance models to augment the measures of situation awareness derived from performance data is explored. Finally, two potential example applications of the proposed assessment techniques are described, one concerning spatial awareness using wide field of view displays and the other emphasizing fault management in aircraft systems.

Tenney, Yvette J.↗

DOE OSTI2017

Virtual machine provisioning, code management, and data movement design for the Fermilab HEPCloud Facility

The Fermilab HEPCloud Facility Project has as its goal to extend the current Fermilab facility interface to provide transparent access to disparate resources including commercial and community clouds, grid federations, and HPC centers. This facility enables experiments to perform the full spectrum of computing tasks, including data-intensive simulation and reconstruction. We have evaluated the use of the commercial cloud to provide elasticity to respond to peaks of demand without overprovisioning local resources. Full scale data-intensive workflows have been successfully completed on Amazon Web Services for two High Energy Physics Experiments, CMS and NOνA, at the scale of 58000 simultaneous cores. This paper describes the significant improvements that were made to the virtual machine provisioning system, code caching system, and data movement system to accomplish this work. The virtual image provisioning and contextualization service was extended to multiple AWS regions, and to support experiment-specific data configurations. A prototype Decision Engine was written to determine the optimal availability zone and instance type to run on, minimizing cost and job interruptions. We have deployed a scalable on-demand caching service to deliver code and database information to jobs running on the commercial cloud. It uses the frontiersquid server and CERN VM File System (CVMFS) clients on EC2 instances and utilizes various services provided by AWS to build the infrastructure (stack). We discuss the architecture and load testing benchmarks on the squid servers. We also describe various approaches that were evaluated to transport experimental data to and from the cloud, and the optimal solutions that were used for the bulk of the data transport. Finally, we summarize lessons learned from this scale test, and our future plans to expand and improve the Fermilab HEP Cloud Facility.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

NASA NTRS1988

Space station integrated propulsion and fluid systems study. Space station program fluid management systems databook

Commonality and integration of propulsion and fluid systems associated with the Space Station elements are being evaluated. The Space Station elements consist of the core station, which includes habitation and laboratory modules, nodes, airlocks, and trusswork; and associated vehicles, platforms, experiments, and payloads. The program is being performed as two discrete tasks. Task 1 investigated the components of the Space Station architecture to determine the feasibility and practicality of commonality and integration among the various propulsion elements. This task was completed. Task 2 is examining integration and commonality among fluid systems which were identified by the Phase B Space Station contractors as being part of the initial operating capability (IOC) and growth Space Station architectures. Requirements and descriptions for reference fluid systems were compiled from Space Station documentation and other sources. The fluid systems being examined are: an experiment gas supply system, an oxygen/hydrogen supply system, an integrated water system, the integrated nitrogen system, and the integrated waste fluids system. Definitions and descriptions of alternate systems were developed, along with analyses and discussions of their benefits and detriments. This databook includes fluid systems descriptions, requirements, schematic diagrams, component lists, and discussions of the fluid systems. In addition, cost comparison are used in some cases to determine the optimum system for a specific task.

Bicknell, B.↗

NASA NTRS1988

A design for a ground-based data management system

An initial design for a ground-based data management system which includes intelligent data abstraction and cataloging is described. The large quantity of data on some current and future NASA missions leads to significant problems in providing scientists with quick access to relevant data. Human screening of data for potential relevance to a particular study is time-consuming and costly. Intelligent databases can provide automatic screening when given relevent scientific parameters and constraints. The data management system would provide, at a minimum, information of availability of the range of data, the type available, specific time periods covered together with data quality information, and related sources of data. The system would inform the user about the primary types of screening, analysis, and methods of presentation available to the user. The system would then aid the user with performing the desired tasks, in such a way that the user need only specify the scientific parameters and objectives, and not worry about specific details for running a particular program. The design contains modules for data abstraction, catalog plan abstraction, a user-friendly interface, and expert systems for data handling, data evaluation, and application analysis. The emphasis is on developing general facilities for data representation, description, analysis, and presentation that will be easily used by scientists directly, thus bypassing the knowledge acquisition bottleneck. Expert system technology is used for many different aspects of the data management system, including the direct user interface, the interface to the data analysis routines, and the analysis of instrument status.

Lambird, Barbara A.↗

DOE OSTI2023

Efficient Probabilistic Prediction and Uncertainty Quantification of Tropical Cyclone–Driven Storm Tides and Inundation

Abstract This study proposes and assesses a methodology to obtain high-quality probabilistic predictions and uncertainty information of near-landfall tropical cyclone–driven (TC-driven) storm tide and inundation with limited time and resources. Forecasts of TC track, intensity, and size are perturbed according to quasi-random Korobov sequences of historical forecast errors with assumed Gaussian and uniform statistical distributions. These perturbations are run in an ensemble of hydrodynamic storm tide model simulations. The resulting set of maximum water surface elevations are dimensionality reduced using Karhunen–Loève expansions and then used as a training set to develop a polynomial chaos (PC) surrogate model from which global sensitivities and probabilistic predictions can be extracted. The maximum water surface elevation is extrapolated over dry points incorporating energy head loss with distance to properly train the surrogate for predicting inundation. We find that the surrogate constructed with third-order PCs using elastic net penalized regression with leave-one-out cross validation provides the most robust fit across training and test sets. Probabilistic predictions of maximum water surface elevation and inundation area by the surrogate model at 48-h lead time for three past U.S. landfalling hurricanes (Irma in 2017, Florence in 2018, and Laura in 2020) are found to be reliable when compared to best track hindcast simulation results, even when trained with as few as 19 samples. The maximum water surface elevation is most sensitive to perpendicular track-offset errors for all three storms. Laura is also highly sensitive to storm size and has the least reliable prediction. Significance Statement The purpose of this study is to develop and evaluate a methodology that can be used to provide high-quality probabilistic predictions of hurricane-induced storm tide and inundation with limited time and resources. This is important for emergency management purposes during or after the landfall of hurricanes. Our results show that sampling forecast errors using quasi-random sequences combined with machine learning techniques that fit polynomial functions to the data are well suited to this task. The polynomial functions also have the benefit of producing exact sensitivity indices of storm tide and inundation to the forecasted hurricane properties such as path, intensity, and size, which can be used for uncertainty estimation. The code implementing the presented methodology is publicly available on GitHub.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2016

Alternate Retrieval A-105 Application Assessment Report

This report summarizes the historical development of the Confined Sluicing End Effector (CSEE) technology as well scarification technology. We also summarize the systems integration and deployment of that technology in the Gunite and Associated Tanks (GAAT) at the Oak Ridge Reservation where the retrieval system successfully removed the remaining sludge and heel in the eight tanks for tank closure and disposition. We also summarize the lessons learned from the deployment at Oak Ridge. Simulant development and testing have been key activities for any waste retrieval effort as many of the physical properties of the waste are unknown; therefore, this report discusses a bounding series of simulants that helps to reduce uncertainty for operations. These simulants have been developed for potential Hanford waste retrieval deployment. The potential key attributes for retrieval, based upon information provided by Washington River Protection Services (WRPS), of single-shell tank A-105 are discussed along with the potential application of CSEE technology to the challenges presented by the unique nature of A-105. These unique features include a major tear in the bottom of the tank, which necessitates technologies other than past practice sluicing to be deployed to prevent further intrusion of waste into the vadose zone. In addition, significant in-tank hardware makes A-105 particular challenging. However, there appear to be a number of parameters that should be investigated through additional testing or review of prior testing that may demonstrate the applicability of the CSEE technology to A-105. Testing of the Waste Retrieval End Effector (WREE), which was based on the original CSEE design, to demonstrate the ability to remove sludge and hardpan from Tank 241-C-106 will be reviewed to determine relevance to the Tank A-105 retrieval. There may be new requirements for the deployment system that accesses the tank with the CSEE because the tank bottom may not be flat, requiring the ability to maneuver the CSEE to maintain the appropriate stand-off distance from the CSEE and the tank bottom. Finally, we provide a set of recommendations, a set of task descriptions, and a range of estimated costs for a demonstration of the technology by the end of FY17. These tasks are summarized as: Complete system-level functional requirements; Procure or access the capacity to perform; Generate simulant development and simulant testing; Develop CSEE functionality; Develop demonstration plan; Perform demonstration; Analyze and document testing results; Perform project management and engineering.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2021

Cardinality-Regularized Hawkes-Granger Model

We propose a new sparse Granger-causal learning framework for temporal event data. We focus on a specific class of point processes called the Hawkes process. We begin by pointing out that most of the existing sparse causal learning algorithms for the Hawkes process suffer from a singularity in maximum likelihood estimation. As a result, their sparse solutions can appear only as numerical artifacts. In this paper, we propose a mathematically well-defined sparse causal learning framework based on a cardinality-regularized Hawkes process, which remedies the pathological issues of existing approaches. We leverage the proposed algorithm for the task of instance-wise causal event analysis, where sparsity plays a critical role. We validate the proposed framework with two real use-cases, one from the power grid and the other from the cloud data center management domain.

Ide, Tsuyoshi↗

DOE OSTI2023

Code for BALDR Study 07.05 v.1.0.0

SAND2024-01293O The Code for BALDR Study 07.05 software reproduces results from the BALDR study concerning "A Semi-Supervised Learning Method to Produce Explainable Radioisotope Proportion Estimates for NaI-based Synthetic and Measured Gamma Spectra." The code for BALDR Study 07.05 can reproduce a scientific study following the step numbers within the file names. Using synthetic and measured data to find the best model for the radioisotope proportion estimation task of interest, the study generated results for inclusion in a paper. The high-level methods involved are neural networks, semi-supervised learning, and out-of-distribution detection. 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.

Morrow, Tyler↗

NASA NTRS1973

Water recovery and solid waste processing for aerospace and domestic applications

The work is described accomplished in compiling information needed to establish the current water supply and waste water processing requirements for dwellings, and for developing a preliminary design for a waste water to potable water management system. Data generated was used in formulation of design criteria for the preliminary design of the waste water to potable water recycling system. The system as defined was sized for a group of 500 dwelling units. Study tasks summarized include: water consumption, nature of domestic water, consumer appliances for low water consumption, water quality monitoring, baseline concept, and current and projected costs.

Murawczyk, C.↗

NASA NTRS1990

Evaluation of the Trajectory Operations Applications Software Task (TOAST). Volume 2: Interview transcripts

The Trajectory Operations Applications Software Task (TOAST) is a software development project whose purpose is to provide trajectory operation pre-mission and real-time support for the Space Shuttle. The purpose of the evaluation was to evaluate TOAST as an Application Manager - to assess current and planned capabilities, compare capabilities to commercially-available off the shelf (COTS) software, and analyze requirements of MCC and Flight Analysis Design System (FADS) for TOAST implementation. As a major part of the data gathering for the evaluation, interviews were conducted with NASA and contractor personnel. Real-time and flight design users, orbit navigation users, the TOAST developers, and management were interviewed. Code reviews and demonstrations were also held. Each of these interviews was videotaped and transcribed as appropriate. Transcripts were edited and are presented chronologically.

Perkins, Sharon↗

NASA NTRS2008

Human Factors in Training

Future space missions will be significantly longer than current Shuttle missions and new systems will be more complex than current systems. Increasing communication delays between crews and Earth-based support means that astronauts need to be prepared to handle the unexpected on their own. As crews become more autonomous, their potential span of control and required expertise must grow to match their autonomy. It is not possible to train for every eventuality ahead of time on the ground, or to maintain trained skills across long intervals of disuse. To adequately prepare NASA personnel for these challenges, new training approaches, methodologies, and tools are required. This research project aims at developing these training capabilities. Training efforts in FY07 strongly focused on crew medical training, but also began exploring how Space Flight Resource Management training for Mission Operations Directorate (MOD) Flight Controllers could be integrated with systems training for optimal Mission Control Center operations. Beginning in January 2008, the training research effort will include team training prototypes and tools. The Training Task addresses Program risks that lie at the intersection of the following three risks identified by the Project: 1) Risk associated with poor task design; 2) Risk of error due to inadequate information; 3) Risk associated with reduced safety and efficiency due to poor human factors design.

Barshi, Immanuel↗

NASA NTRSDate not supplied

SafeMAP: Safe Multi-Agent Planning Framework Based on Dynamic Probabilistic Risk Assessment

This paper proposes a risk-aware framework for Safe Multi-Agent Planning (SafeMAP) that unifies disparate models for multi-agent systems in a Markovian process that allows for simultaneous system health monitoring, decision making under uncertainty, and multi-agent system collaboration. As operations beyond low earth orbit mature, there is an increased need for autonomous cyber-physical systems with onboard decision making capabilities. Multi-agent cyber-physical systems in particular offer the potential of increased efficiency, resiliency, and mission capabilities for future applications such as multi-rover terrain operations, distributed satellite operations, and management of smart lunar habitats. SafeMAP utilizes physics-based models of each agent and the relevant components, probability models of the environment and component operational states, and reward models for mission-specific objectives such as scientific task completion or resource consumption. The output of SafeMAP is a set of mission plans that satisfy the mission objective under specified risk/reward constraints. A readable interpretation of each of these generated mission plans is provided as an additional output. SafeMAP has been demonstrated on a simulated case study involving a four-rover system performing surface mapping operations and science tasks. Results of this paper demonstrate SafeMAP’s ability to generate explainable mission plans that satisfy the mission objective while minimizing risk under nominal and off-nominal conditions.

Mohammad Hejase↗

NASA NTRSDate not supplied

SafeMAP: Safe Multi-Agent Planning framework based on Dynamic Probabilistic Risk Assessment

Mohammad Hejase↗

NASA NTRSDate not supplied

Modeling NASA’s Procedural Requirement Processes - Implications for Digital Future

The National Aeronautics and Space Administration (NASA) has an ongoing Digital Transformation effort and to leverage and showcase the power of Digital Transformation, an effort is underway to develop an integrated, datacentric, model representing NASA’s key process requirements. The task was divided into three phases: As Is modeling, Analysis, and To Be Planning. As part of this effort, a team has completed the first Phase I of the modeling task and is nearing completion of the second phase. This effort will capture the key elements as requirements, responsibilities, allocations, roles, products, and associated lifecycle elements. The scope of modeling included NASA’s NPR 7120.5 (Project and Program Management), NPR 7123.1 (Systems Engineering) and NPRs 8705.2 (Risk classification for Robotic Missions) and 8705.4 (Human-Rating Requirements for Space Missions). This paper will summarize the approach, scope, parsing patterns applied, metamodel, and associated workflows for the As-Is modeling. It will also summarize the results and insights gleaned during that phase, including the review process. These insights have informed the analysis and will be discussed. The analysis modeling phase will also be summarized including how the stakeholders were engaged, how the common elements were handled and dispositioned, and will also describe some of the plans for the future of NASA NPDs and NPRs.

Systems Engineering↗

Refine your search to explore more results.