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Large-Scale System Monitoring Experiences and Recommendations

Ahlgren, V.; Andersson, S.; Brandt, James M.; Cardo, N.; Chunduri, S.; Enos, J.; Fields, P.; Gentile, Ann C.; Gerber, R.; Gienger, M.; Greenseid, J.; Greiner, A.; Hadri, B.; He, Y.; Hoppe, D.; Kaila, U.; Kelly, K.; Klein, M.; Kristiansen, A.; Leak, S.; Mason, M.; Foulk, James W.; Piccinali, J-G; Repik, Jason J.; Rogers, J.; Salminen, S.; Showerman, M.; Whitney, C.; Williams, J.

Abstract not provided.

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TYPE Conference Poster YEAR 2018
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Mechanical Properties of Woven Composites at Ambient Temperature

Jin, Helena; Lu, Wei-Yang; Nissen, April E.H.; Nelson, Kevin; Briggs, Timothy

This report describes the mechanical characterization of six types of woven composites that Sandia National Laboratories are interested in. These six composites have various combinations of two types of fibers (Carbon-IM7 and Glass-S2) and three types of resins (UF-3362, TC275-1, TC350-1). In this work, two sets of experiments were conducted: quasi-static loading with displacement rate of 2 mm/min (1.3x10^(-3) in/s) and high rate loading with displacement of 5.08 m/s (200 in/s). Quasi-static experiments were performed at three loading orientations of 0°, 45°, 90° for all the six composites to fully characterize their mechanical properties. The elastic properties Young's modulus and Poisson's ratio, as well as ultimate stress and strain were obtained from the quasi-static experiments. The high strain rate experiments were performed only on glass fiber composites along 0° angle of loading. The high rate experiments were mainly to study how the strain rate affects the ultimate stress of the glass-fiber composites with different resins.

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TYPE SAND Report YEAR 2018
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Bi-fidelity approximation for uncertainty quantification and sensitivity analysis of irradiated particle-laden turbulence

Geraci, Gianluca; Fairbanks, Hillary; Jofre, Lluis; Iaccarino, Gianluca; Doostan, Alireza

Efficiently performing predictive studies of irradiated particle-laden turbulent flows has the potential of providing significant contributions towards better understanding and optimizing, for example, concentrated solar power systems. As there are many uncertainties inherent in such flows, conducting uncertainty quantification analyses is fundamental to improve the predictive capabilities of the numerical simulations. For largescale, multi-physics problems exhibiting high-dimensional uncertainty, characterizing the stochastic solution presents a significant computational challenge as many methods require a large number of high-fidelity, forward model solves. This requirement results in the need for a possibly infeasible number of simulations when a typical converged high-fidelity simulation requires intensive computational resources. To reduce the cost of quantifying high-dimensional uncertainties, we investigate the application of a non-intrusive, bi-fidelity approximation to estimate statistics of quantities of interest associated with an irradiated particle-laden turbulent flow. This method relies on exploiting the low-rank structure of the solution to accelerate the stochastic sampling and approximation processes by means of cheaper-to-run, lower fidelity representations. The application of this bi-fidelity approximation results in accurate estimates of the QoI statistics while requiring a small number of high-fidelity model evaluations. It also enables efficient computation of sensitivity analyses which highlight that epistemic uncertainty plays an important role in the solution of irradiated, particle-laden turbulent flow.

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TYPE Other Report YEAR 2018
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Mechanical Characterization of Woven Composites at Different Temperatures

Jin, Helena; Briggs, Timothy; Nissen, April E.H.; Nelson, Kevin

This work is to characterize the mechanical properties of the selected composites along both on- and off- fiber axes at the ambient loading condition (+25°C), as well as at the cold (-54°C), and high temperatures (+71°C). A series of tensile experiments were conducted at different material orientations of 0°, 22.5°, 45°, 67.5°, 90° to measure the ultimate strength and strain $σ_{f}, ϵ_{f}$, and material engineering constants, including Young's modulus Ε and Poisson's ratio ν. The composite materials in this study were one carbon composite carbon (AS4C/UF3662) and one E-galss (E-glass/UF3662) composite. They both had the same resin of UF 3362, but with different fibers of carbon AS4C and E-glass. The mechanical loading in this study was limited to the quasi-static loading of 2 mm/min (1.3x10^(-3) in/s), which was equivalent to 5x10(-4) strain rate. These experimental data of the mechanical properties of composites at different loading directions and temperatures were summarized and compared. These experimental results provided database for design engineers to optimize structures through ply angle modifications and for analysts to better predict the component performance.

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TYPE SAND Report YEAR 2018
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Characterization of Cement-Geomaterial Interfaces for Subsurface Applications

Steen, McKalee

Subsurface seals and wellbores are central to oil and gas production, as well as the containment of subsurface fluids (e.g. methane or CO2 storage). Studying the evolution of cement-geomaterial interfaces of such systems is important to further our understanding of the fundamental physics and chemistry that underpins catastrophic wellbore seal failure. The objective of this study is to characterize cementitious and geomaterials through pore structure analysis and geochemical modeling. A variety of methods exist to characterize the pore structures and mineralogy of porous systems like cements and subsurface host rocks. This study will utilize traditional porosimetry techniques such as BET and IP, as well as more advanced methods using electron image analysis, to gain a more accurate understanding of pore geometries. The results of this study can help further the understanding of how cementitious materials will evolve, and can be used as inputs to field scale models used to predict wellbore behavior over time.

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TYPE Other Report YEAR 2018
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Standoff Over the LRSO: Assessing the long-range stand-off missile's impact on strategic stability

Heimer, Brandon W.

Mutual vulnerability to strategic forces seems to remain the de facto foundation for strategic stability across the U.S.-Russia and U.S.-China dyadic relationships; This work has suggested the bomber force tasked with delivering the LRSO is characterized by relatively long flight times and rich signature sets which make its use inconsistent with the requirements for a disarming first-strike. Therefore, the LRSO would not be expected to disrupt mutual vulnerability by making a disarming strike more possible or attractive; Even if a stealthy air-launched cruise missile is paired with a stealth bomber aircraft, the signatures associated with bomber generation and aerial refueling from non-stealth tanker aircraft make it unlikely the LRSO could be launched against a peer or near-peer nation-state without advance warning; To the extent a nuclear armed air-launched cruise missile deters would-be U.S. adversaries from nuclear use, maintaining a survivable weapon system is crucial for maintaining that stable deterrent effect. A modern stand-off weapon and stealth delivery platform increase the probability this capability will be maintained in the future against other nations' increasingly capable A2/AD systems; The LRSO has been touted as a flexible option to deter, or conduct should deterrence fail, limited nuclear strikes pursuant to Russia's reported "escalate-to-deescalate" doctrine. The concept of limited nuclear use is still intensely debated, and there is no guarantee that escalation could be controlled even with tailored LRSO employment; The challenge of warhead discrimination has not historically led to a nuclear response to a cruise missile launch, but there is no guarantee that cannot change. Having accurate military intelligence coupled with discerning analysis of the context in which cruise missiles are employed (e.g., how escalated is the conflict, how many missiles have been launched, have there been signatures of strategic force mobilization, or has the nuclear threshold been crossed?) will likely be essential for reducing the danger of misperception. Developing norms and/or communication channels in the aforementioned dyadic relationships may also further these ends. In sum, this work has identified and analyzed many of the major arguments in the debate regarding the LRSO's impact on strategic stability. During this study and survey of other nation's conceptions of strategic stability, it became clear that the LRSO is neither inherently stabilizing or destabilizing; rather, it is one instrument in addition to unambiguous U.S. policy, clear messaging, and signaling of intent that may promote stability by reducing the risk of miscalculation and unintended escalation.

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TYPE Other Report YEAR 2018
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HERMES Outdoor Shot Series 10268-313: Data Analysis as a Model for Output Voltage and Current Estimates for HERMES Shots; a User Perspective

Renk, Timothy J.

The primary subject of this Report is the description and characterization of results (voltages, currents, radiation dose and dose-rates) from the HERMES accelerator operated in the Outdoor Mode. The shots described range from 10266 – 10313, and were taken in late 2016. In the course of determining the most accurate estimates of voltage and current, a prescriptive procedure is developed to process the raw data posted to the HERMES database. The current estimates are tied to voltage determination using the MITL theory of Mendel, as modified by Schumer and Ottinger. The converter currents are accurately recorded due to newly calibrated monitors at the converter location. Additional historical information about the development of the HERMES current monitor set is included to enhance the archival value of this Report. The evolution of the TLD faceplate profile from non-peaked center to center-peaked is discussed, with hypotheses as to the cause. The prescriptive procedure discussed herein is accurate as of the day of printing. Should the prescription be modified and updated, this Report would also need updating.

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TYPE SAND Report YEAR 2018
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Rapid high-fidelity aerothermal responses with quantified uncertainties via reduced-order modeling

Carlberg, Kevin T.; Howard, Micah; Freno, Brian A.

This project will enable high-fidelity aerothermal simulations of hypersonic vehicles to be employed (1) to generate large databases with quantified uncertainties and (2) for rapid interactive simulation. The databases will increase the volume/quality of A4H data; rapid interactive simulation can enable arbitrary conditions/designs to be simulated on demand. We will achieve this by applying reduced-order-modeling techniques to aerothermal simulations.

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TYPE Other Report YEAR 2018
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Summary of Observations from the 2017 Federal Radiological Monitoring and Assessment Center (FRMAC) Laboratory Analysis Training and Capstone Event

Fournier, Sean D.; Shanks, Sonoya T.; Allen, Mark B.; Leonard, Elliott

On August 15th thru 17th, 2017 the Federal Radiological Monitoring and Assessment Center (FRMAC) Laboratory Analysis division, the FRMAC Fly Away Laboratory (FAL), the FRMAC Assessment division, and the Mobile Environmental Response Laboratory (MERL) held a training and capstone event for staff from the Environmental Protection Agency (EPA), Remote Sensing Laboratory (RSL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories (SNL). LAB-100, "Sample Control Training", LAB-200 "QA Specialist Training", and LAB-300 "Laboratory Analysis Manager Training" was given the first two days of the event. The purpose of the training and capstone event was to meet training requirements for billeted FRMAC Lab Analysis staff from RSL, LLNL, and SNL as well as raise awareness of the FRMAC Lab Analysis process with EPA staff as part of a Federal Emergency Management Agency — Nuclear Incident Response Team (FEMA-NIRT) laboratory standardization project. An objective of the standardization project was to help improve the transition of operations from DOE to EPA during a response. To do this effectively, detailed knowledge of the FRMAC Lab Analysis process by the EPA is needed. This training provided a good opportunity for this knowledge transfer. A capstone was held after the two-day training event to allow participants to practice the skills they learned in a realistic scenario. A scenario that was previously developed for a quarterly Consequence Management drill (i.e. Dark Phoenix) was used as the basis for the capstone, with laboratory analysis focused injects used to drive the exercise play. Each position within the FRMAC Lab Analysis Division exercised to specific objectives and helped to uncover gaps in the established processes. The lessons learned during this capstone are broken out in the following categories: Sample Control, In-Situ Gamma Spectroscopy, Analysis Request Forms (ARF), Shipping, QA/QC, Fly Away Laboratory (FAL), and Management.

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TYPE Other Report YEAR 2018
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Fast Approximate Union Volume in High Dimensions with Line Samples

Mitchell, Scott A.; Awad, Muhammad A.; Ebeida, Mohamed; Swiler, Laura P.

The classical problem of calculating the volume of the union of d-dimensional balls is known as "Union Volume." We present line-sampling approximation algorithms for Union Volume. Our methods may be extended to other Boolean operations, such as setminus; or to other shapes, such as hyper-rectangles. The deterministic, exact approaches for Union Volume do not scale well to high dimensions. However, we adapt several of these exact approaches to approximation algorithms based on sampling. We perform local sampling within each ball using lines. We have several variations, depending on how the overlapping volume is partitioned, and depending on whether radial, axis-aligned, or other line patterns are used. Our variations fall within the family of Monte Carlo sampling, and hence have about the same theoretical convergence rate, 1 /$\sqrt{M}$, where M is the number of samples. In our limited experiments, line-sampling proved more accurate per unit work than point samples, because a line sample provides more information, and the analytic equation for a sphere makes the calculation almost as fast. We performed a limited empirical study of the efficiency of these variations. We suggest a more extensive study for future work. We speculate that different ball arrangements, differentiated by the distribution of overlaps in terms of volume and degree, will benefit the most from patterns of line samples that preferentially capture those overlaps. Acknowledgement We thank Karl Bringman for explaining his BF-ApproxUnion (ApproxUnion) algorithm [3] to us. We thank Josiah Manson for pointing out that spoke darts oversample the center and we might get a better answer by uniform sampling. We thank Vijay Natarajan for suggesting random chord sampling. The authors are grateful to Brian Adams, Keith Dalbey, and Vicente Romero for useful technical discussions. This work was sponsored by the Laboratory Directed Research and Development (LDRD) Program at Sandia National Laboratories. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research (ASCR), Applied Mathematics Program. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and 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.

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TYPE SAND Report YEAR 2018
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Lessons from Past Nuclear Disarmament: What Worked What Did Not

Forden, Geoffrey

This report studies the efforts of the international community and the United States to verif)/ the denuclearization of various countries: Ukraine, South Africa, Iraq, Taiwan, and Libya. In doing so, it considers the verification of nuclear warhead destruction and the accounting of nuclear materials. Each case study contributes to the understanding we have of which verification procedures worked and which did not and what factors contributed to that success and which did not. The most important factor contributing to successful verification is the cooperation of the subject country. If a country has made the strategic decision to cooperate, then it is possible that verification can be successful. If the country chooses not to cooperate, verification might rest on random and unpredictable events. This unpredictability of verification is politically unacceptable. Even if verification is judged to be successful by the implementing agencies, outsiders can cast doubts on it by pointing out small and potentially unavoidable errors in material amounts verified. It is vitally important to systematically preserve forensic evidence, especially shipping and receiving records to avoid just such issues. Historically, such records are the most important evidence in verifying denuclearization. Technology is far less important than forensic analysis of records. It does play a supporting role in verifying some declarations but there can be an enormous delay in drawing conclusions caused by the necessity to analyze statistically large samples of materials. The confidence one gets from such analysis can be delayed well past the time it is politically significant. The most important advance in technology would be to accelerate that sample analysis process.

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TYPE SAND Report YEAR 2018
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Formulas For Plane Wave Coupling To A Transmission Line Above Ground With Terminating Loads

Warne, Larry K.; Campione, Salvatore

This report considers plane wave coupling to a transmission line consisting of a wire above a conducting ground. Comparisons are made for the two types of available source models, along with a discussion about the decomposition of the line currents. Simple circuit models are constructed for the terminating impedances at the ends of the line including radiation effects. Results from the transmission line with these loads show good agreement with full wave simulations.

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TYPE SAND Report YEAR 2018
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Causal Analysis Report for NA-SS-SNL-8000-2018-0002 Electrical shock: Wind Turbine Nacelle Lubbock TX

Wright, Emily D.

A Sandia National Laboratories Member of the Workforce (MOW) experienced contact with electrical energy while performing work on an oil filter pump electrical system in the al wind turbine nacelle at Sandia National Laboratories Scaled Wind Turbine Facility (SWiFT). The Department of Energy (DOE) Sandia National Laboratories (SNL) Scaled Wind Farm Technology (SWiFT) facility does research and development (R&D) work in collaboration with Texas Tech University. The SWiFT facility includes three turbines for performing wind plant and turbine technology research in support of DOE's Wind Energy Technology Office. The current work ongoing at the site is primarily related to commissioning the three turbines to support ongoing DOE customer needs and requests. It was during the performance of commissioning tests of the hydraulic systems in the a1 turbine that a Sandia MOW experienced contact with electrical energy. There were multiple root and contributing causes that ultimately resulted in the electrical energy contact. These causes are summarized and aligned to their corrective actions in the corrective action plan table provided in Section 7(c). The purpose of this narrative section is to provide additional information and context

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TYPE Other Report YEAR 2018
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Hearst Health Prize for Excellence in Population Health

Thomas, Jennifer L.

Sandia National Laboratories (SNL) Employee Health Services (EHS) is committed to promoting healthy, vibrant lives and embracing health. Since 1986, EHS has built a comprehensive, evidence-based program designed to measure and assess health risk prevalence, provide targeted and customizable services to address health risks, incentivize healthy behaviors, improve productivity, enhance quality of life, and lower healthcare costs for participants via collaboration between on-site and community-based providers. This unique partnership provides a broad scope of services that may not be available to employees solely through their health benefit plan, and allows a supportive, convenient approach that has proven enhanced health outcomes. EHS impacts over 12,000 SNL employees in Albuquerque, New Mexico. Corporate wellness is as important as ever as health issues and healthcare costs continue to rise. We use the 8-15-80 model as the foundation for our health program strategy: prevent or improve 8 modifiable behaviors and risks that contribute to 15 chronic health conditions that account for 80% of healthcare spending on chronic illnesses worldwide. We utilize patient-centered, cost-effective, community-connected care by providing free onsite services including the NCQA-recognized/AAAHC-accredited medical clinic, health management, preventive health, behavioral health, physical therapy, medical case management, acute care, emergency medical services, and more. These programs and services are an employer-paid benefit open to all SNL employees. The organization combines best practices, accredited programs, and top health care providers to bring employees the most comprehensive approach to health care.

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TYPE Other Report YEAR 2018
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Updated Verification and Validation Assessment for VERA

Mattie, Patrick

The Virtual Environment for Reactor Applications (VERA) code suite is assessed in terms of capability and credibility against the Consortium for Advanced Simulation of Light Water Reactors (CASL) Verification and Validation Plan (presented herein) in the context of three selected challenge problems: CRUD-Induced Power Shift (CIPS), Departure from Nucleate Boiling (DNB), and Pellet-Clad Interaction (PCI). Capability refers to evidence of required functionality for capturing phenomena of interest while credibility refers to the evidence that provides confidence in the calculated results. For this assessment, each challenge problem defines a set of phenomenological requirements against which the VERA software is assessed. This approach, in turn, enables the focused assessment of only those capabilities relevant to the challenge problem. The evaluation of VERA against the challenge problem requirements represents a capability assessment. The mechanism for assessment is the Sandia-developed Predictive Capability Maturity Model (PCMM) that, for this assessment, evaluates VERA on 8 major criteria: (1) Representation and Geometric Fidelity, (2) Physics and Material Model Fidelity, (3) Software Quality Assurance and Engineering, (4) Code Verification, (5) Solution Verification, (6) Separate Effects Model Validation, (7) Integral Effects Model Validation, and (8) Uncertainty Quantification. For each attribute, a maturity score from zero to three is assigned in the context of each challenge problem. The evaluation of these eight elements constitutes the credibility assessment for VERA.

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TYPE Other Report YEAR 2018
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DC Microgrid Protection: Review and Challenges

Augustine, Sijo; Quiroz, Jimmy E.; Reno, Matthew J.; Brahma, Sukumar

Successful system protection is critical to the feasibility of the DC microgrid system. This work focused on identifying the types of faults, challenges of protection, different fault detection schemes, and devices pertinent to DC microgrid systems. One of the main challenges of DC microgrid protection is the lack of guidelines and standards. The various parameters that improve the design of protection schemes were identified and discussed. Due to the absence of physical inertia, the resistive nature of the line impedance affects fault clearing time and system stability during faults. Therefore, the effectiveness of protection coordination systems with communication were also explored. A detailed literature review was done to identify possible grounding schemes and protection devices needed to ensure seamless power flow of grid-connected DC microgrids. Ultimately, it was identified that more analyses and experimentation are needed to develop optimized fault detection schemes with reduced fault clearing time.

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TYPE SAND Report YEAR 2018
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Instructions for the Installation and Testing on a Windows System of the Sandia Automatic Report Generator

Perrinel, Meriadeg; Pebay, Philippe P.; Clay, Robert L.

This report is a sequel to [PC18], where we provided the detailed installation and testing instructions of Sandia's currently-being-developed Automatic Report Generator (ARG), for both Linux and macOS target platforms. In the current report, we extend these instructions to the case of Windows systems.

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TYPE SAND Report YEAR 2018
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A Wolter Imager on the Z Machine to Diagnose Warm X-ray Sources

Fein, Jeffrey R.; Ampleford, David J.; Vogel, Julia; Kozioziemski, Bernie; Walton, Christopher; Wu, Ming; Ames, Andrew; Ayers, J.; Ball, Christopher R.; Bell, Perry; Bourdon, Christopher; Bradley, David; Bruni, R.; Gard, Paul D.; Kilaru, K.; Lake, Patrick; Maurer, Andrew J.; Pickworth, Louisa; Pivovaroff, Michael; Ramsey, Brian; Roberts, Oliver; Romaine, Suzanne; Sullivan, Michael A.; Kirtley, Christopher K.

Abstract not provided.

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TYPE Presentation YEAR 2018
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Framework for The Analysis of US Permanent Geologic Disposal Options for Radioactive Waste

Bonano, Evaristo J.

The U.S. study of permanent geologic disposal options of spent nuclear fuel (SNF) and high-level radioactive waste (HLW) provided a technical basis for informing policy decisions regarding strategies for the management and disposal of radioactive waste requiring geologic isolation through the evaluation of potential impacts of waste forms on the feasibility and performance of representative generic concepts for geologic disposal. The goal of the study was to help inform relevant policy questions including: Is a "one-size-fits-all" repository a good strategic option for disposal? Do different waste types and forms perform differently enough in different disposal concepts that they warrant different treatment? Do some disposal concepts perform significantly better with or without specific waste types or forms?

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TYPE Other Report YEAR 2018
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Optimal Floating Vertical-Axis Wind Turbine Platform Identification Design and Cost Estimation

Ennis, Brandon L.

This report houses the deliverables provided by Stress Engineering Services on the floating platform design identification studies and the detailed final design iterations. The results were obtained under contract to and in partnership with Sandia to iterate between the platform design and the aero-hydro-elastic load simulations of the coupled vertical-axis wind turbine system. Through the analysis summarized in this report, a tension-leg platform with multiple columns was identified as the optimal platform when considering cost and performance. The detailed design and cost estimate of this platform architecture was produced in the final phase of study which is also described within this report.

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TYPE SAND Report YEAR 2018
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Results 28201–28400 of 99,299
Results 28201–28400 of 99,299