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Guidance on the Technology Performance Level (TPL) Assessment Methodology

Roberts, Jesse D.; Bull, Diana L.; Weber, Jochem; Babarit, Aurelien; Costello, Ronan; Neilson, Kim; Kennedy, Ben; Malins, Robert J.; Dykes, Katherine

This document presents the revised Technology Performance Level (TPL) assessment methodology. There are three parts to this revised methodology 1) the Stakeholder Needs and Assessment Guidance (this document), 2) the Technical Submission form, 3) the TPL scoring spreadsheet. The TPL assessment is designed to give a technology neutral or agnostic assessment of any wave energy converter technology. The focus of the TPL is on the performance of the technology in meeting the customer’s needs. The original TPL is described in [1, 2] and those references also detail the critical differences in the nature of the TPL when compared to the more widely used technology readiness level (TRL). (Wave energy TRL is described in [3]). The revised TPL is particularly intended to be useful to investors and also to assist technology developers to conduct comprehensive assessments in a way that is meaningful and attractive to investors. The revised TPL assessment methodology has been derived through a structured Systems Engineering approach. This was a formal process which involved analyzing customer and stakeholder needs through the discipline of Systems Engineering. The results of the process confirmed the high level of completeness of the original methodology presented in [1] (as used in the Wave Energy Prize judging) and now add a significantly increased level of detail in the assessment and an improved more investment focused structure. The revised TPL also incorporates the feedback of the Wave Energy Prize judges.

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Technology Performance Level (TPL) Scoring Tool

Roberts, Jesse D.; Bull, Diana L.; Weber, Jochem; Costello, Ronan; Babarit, Aurelien; Neilson, Kim; Bittencourt, Claudio; Kennedy, Ben

Three different ways of combining scores are used in the revised formulation. These are arithmetic mean, geometric mean and multiplication with normalisation. Arithmetic mean is used when combining scores that measure similar attributes, e.g. used for combining costs. The arithmetic mean has the property that it is similar to a logical OR, e.g. when combining costs it does not matter what the individual costs are only what the combined cost is. Geometric mean and Multiplication are used when combining scores that measure disparate attributes. Multiplication is similar to a logical AND, it is used to combine ‘must haves.’ As a result, this method is more punitive than the geometric mean; to get a good score in the combined result it is necessary to have a good score in ALL of the inputs. e.g. the different types of survivability are ‘must haves.’ On balance, the revised TPL is probably less punitive than the previous spreadsheet, multiplication is used sparingly as a method of combining scores. This is in line with the feedback of the Wave Energy Prize judges.

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Statistical Approach for Determining the Sandia Array Performance Model Coefficients that Considers String-Level Mismatch

Jones, Christian B.; Hansen, Clifford; King, Bruce H.

Commonly used performance models, such as PVsyst, Sandia Array Performance Model (SAPM), and PV LIB, treat the PV array as being constructed of identical modules. Each of the models attempts to account for mismatch losses by applying a simple percent reduction factor to the overall estimated power. The present work attempted to reduce uncertainty of mismatch losses by determining a representative set of performance coefficients for the SAPM that were developed from a characterization of a sample of modules. This approach was compared with current practice, where only a single module’s thermal and electrical properties are testing. However, the results indicate that minimal to no improvements in model predictions were achieved.

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Solid-state-based analog of optomechanics

Journal of the Optical Society of America. Part B, Optical Physics

Naumann, Nicolas L.; Droenner, Leon; Carmele, Alexander; Chow, Weng W.; Kabuss, Julia

In this study, we investigate a semiconductor quantum dot as a microscopic analog of a basic optomechanical setup. We show that optomechanical features can be reproduced by the solid-state platform, arising from parallels of the underlying interaction processes, which in the optomechanical case is the radiation pressure coupling and in the semiconductor case the electron–phonon coupling. We discuss bistabilities, lasing, and phonon damping, and recover the same qualitative behaviors for the semiconductor and the optomechanical cases expected for low driving strengths. However, in contrast to the optomechanical case, distinct signatures of higher order processes arise in the semiconductor model.

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(Active) Learning on Groups of Data with Information-Theoretic Estimators

Sutherland, Dougal; Kegelmeyer, William P.; Hutchinson, Robert L.

A wide range of machine learning problems, including astronomical inference about galaxy clusters, scene classification, parametric statistical inference, and predictions of public opinion, can be well-modeled as learning a function on (samples from) distributions. This project explores problems in learning such functions via kernel methods, particularly for large-scale problems. When learning from large numbers of distributions, the computation of typical methods scales between quadratically and cubically, and so they are not amenable to large datasets. We investigate the approach of approximate embeddings into Euclidean spaces such that inner products in the embedding space approximate kernel values between the source distributions. We first improve the understanding of the workhorse methods of random Fourier features: we show that of the two approaches in common usage, one is strictly superior. We then present a new embedding for a class of information-theoretic distribution distances, and evaluate it and existing embeddings on several real-world applications.

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Evaluating the Opportunities for Multi-Level Memory – An ASC 2016 L2 Milestone

Voskuilen, Gwendolyn R.; Rodrigues, Arun; Frank, Michael P.; Hammond, Simon

The next two Advanced Technology platforms for the ASC program will feature complex memory hierarchies – in the Trinity supercomputer being deployed in 2016, Intel’s Knights Landing processors will feature 16GB of on-package, high-bandwidth memory, combined with a larger capacity DDR4 memory and in 2018, the Sierra machine deployed at Lawrence Livermore National Laboratory will feature powerful compute nodes containing POWER9 processors with large capacity memories and an array of coherent GPU accelerators also with high bandwidth memories.

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Well Integrity for Natural Gas Storage in Depleted Reservoirs and Aquifers

Bauer, Stephen J.; Blankenship, Douglas A.; Roberts, Barry L.

The 2015-2016 Aliso Canyon/Porter Ranch natural gas well blowout emitted approximately 100,000 tonnes of natural gas (mostly methane, CH4) over four months. The blowout impacted thousands of nearby residents, who were displaced from their homes. The high visibility of the event has led to increased scrutiny of the safety of natural gas storage at the Aliso Canyon facility, as well as broader concern for natural gas storage integrity throughout the country. This report presents the findings of the DOE National Laboratories Well Integrity Work Group efforts in the four tasks. In addition to documenting the work of the Work Group, this report presents high priority recommendations to improve well integrity and reduce the likelihood and consequences of subsurface natural gas leaks.

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Optimization of Isentropic Compression Loads on Current-Adder Pulsed Power Accelerator Architectures

Reisman, David; Waisman, Eduardo M.; Stoltzfus, Brian; Stygar, William A.; Cuneo, Michael E.; Haill, Thomas A.; Davis, Jean-Paul; Brown, Justin L.; Seagle, Christopher T.; Spielman, Rick B.

The Thor pulsed power generator is being developed at Sandia National Laboratories. The design consists of up to 288 decoupled and transit time isolated capacitor-switch units, called “bricks”, that can be individually triggered to achieve a high degree of pulse tailoring for magnetically-driven isentropic compression experiments (ICE). The connecting transmission lines are impedance matched to the bricks, allowing the capacitor energy to be efficiently delivered to an ICE strip-line load with peak pressures of over 100 GPa. Thor will drive experiments to explore equation of state, material strength, and phase transition properties of a wide variety of materials. We present an optimization process for producing tailored current pulses, a requirement for many material studies, on the Thor generator. This technique, which is unique to the novel “current-adder” architecture used by Thor, entirely avoids the iterative use of complex circuit models to converge to the desired electrical pulse. We describe the optimization procedure for the Thor design and show results for various materials of interest. Also, we discuss the extension of these concepts to the megajoule-class Neptune machine design. Given this design, we are able to design shockless ramp-driven experiments in the 1 TPa range of material pressure.

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Frontier Observatory for Research in Geothermal Energy: Phase 1 Topical Report Fallon, NV

Blankenship, Douglas A.

The Department of Energy (DOE) Frontier Observatory for Research in Geothermal Energy (FORGE) is to be a dedicated site where the subsurface scientific and engineering community can develop, test, and improve technologies and techniques for the creation of cost-effective and sustainable enhanced geothermal systems (EGS) in a controlled, ideal environment. The establishment of FORGE will facilitate development of an understanding of the key mechanisms controlling a successful EGS. Execution of FORGE is occurring in three phases with five distinct sub-phases (1, 2A, 2B, 2C, and 3). This report focuses on Phase 1 activities. During Phase 1, critical technical and logistical tasks necessary to demonstrate the viability of the Fallon FORGE Project site were completed and the commitment and capability of the Fallon FORGE team to execute FORGE was demonstrated. As part of Phase 1, the Fallon FORGE Team provided an assessment of available relevant data and integrated these geologic and geophysical data to develop a conceptual 3-D geologic model of the proposed test location. Additionally, the team prepared relevant operational plans for full FORGE implementation, provided relevant site data to the science and engineering community, engaged in outreach and communications with interested stakeholders, and performed a review of the environmental and permitting activities needed to allow FORGE to progress through Phase 3. The results of these activities are provided as Appendices to this report. The Fallon FORGE Team is diverse, with deep roots in geothermal science and engineering. The institutions and key personnel that comprise the Fallon FORGE Team provide a breadth of geoscience and geoengineering capabilities, a strong and productive history in geothermal research and applications, and the capability and experience to manage projects with the complexity anticipated for FORGE. Fallon FORGE Team members include the U.S. Navy, Ormat Nevada Inc., Sandia National Laboratories (SNL), Lawrence Berkeley National Laboratory (LBNL), the United States Geological Survey (USGS), the University of Nevada, Reno (UNR), GeothermEx/Schlumberger (GeothelinEx), and Itasca Consulting Group (Itasca). The site owners (through direct land ownership or via applicable permits)—the U.S. Navy and Ormat Nevada Inc.—are deeply committed to expanding the development of geothermal resources and are fully supportive of FORGE operations taking place on their lands.

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Frontier Observatory for Research in Geothermal Energy: Phase 1 Topical Report West Flank of Coso, CA

Blankenship, Douglas A.

The Department of Energy (DOE) Frontier Observatory for Research in Geothermal Energy (FORGE) is to be a dedicated site where the subsurface scientific and engineering community can develop, test, and improve technologies and techniques for the creation of cost-effective and sustainable enhanced geothermal systems (EGS) in a controlled, ideal environment. The establishment of FORGE will facilitate development of an understanding of the key mechanisms controlling a successful EGS. Execution of FORGE is occurring in three phases with five distinct sub-phases (1, 2A, 2B, 2C, and 3). This report focuses on Phase 1 activities.

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Institutional Transformation (IX) 2.5 Building Module Help Manual

Villa, Daniel L.

The Institutional Transformation (IX) building module is a software tool developed at Sandia National Laboratories to evaluate energy conservation measures (ECMs) on hundreds of DOE-2 building energy models simultaneously. In IX, ECMs can be designed through parameterizing DOE-2 building models and doing further processing via visual basic for applications subroutines. IX provides the functionality to handle multiple building models for different years, which enables incrementally changing a site of hundreds of buildings over time. It also enables evaluation of the effects of changing climate, comparisons between data and modeling results, and energy use of centralized utility buildings (CUBs). IX consists of a Microsoft Excel® user interface, Microsoft Access® database, and Microsoft Excel® CUB build utility whose functionalities are described in detail in this report. In addition to descriptions of the user interfaces, descriptions of every ECM already designed in IX is included.

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A bound on electromagnetic penetration through a slot aperture with backing cavity

Warne, Larry K.; Jorgenson, Roy E.; Williams, Jeffery T.; Basilio, Lorena I.; Coats, Rebecca S.; Campione, Salvatore; Chen, Kenneth C.; Langston, William L.

This report examines bounds on the penetrant power through ports of entry into a conductive cavity. We first replace the cavity by a load and consider the maximum power transfer properties of an antenna or an aperture. We consider how limitations on the load quality factor place limits on received power. For general frequency ranges we model the backing region by means of a uniformly distributed matched load along a slot aperture and adjust its value for maximum power transfer. This result is derived in closed form using a transmission line model for the aperture. This result illustrates the reduction in received power for low frequencies with finitely conducting wall materials. At high frequencies it approaches the receiving cross section of a linear array having the slot length dimension. Next we examine a slot aperture in a conducting rectangular enclosure and determine how the cavity wall losses and resulting quality factor limit the penetrant power. Detailed simulations and experimental measurements are compared with each other and with the bounding results to assess the accuracy of the bounds. These comparisons also indicate limitations on the accuracy of the models due to perturbing influences in construction, such as bolted joints.

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Intermediate Scale Testing Recommendation Report

Hansen, Francis D.; Sobolik, Steven; Stauffer, Phil H.

A summary of recommendations for near-term intermediate-scale testing pertaining to a salt repository is provided in this report. Each proposal was asked to implement a phased progression, initiating with test plan production in FY 2017 and early-stage testing, if possible. Beyond 2017, testing is anticipated to progress to an underground setting and involve intermediate-scale field activities. Each test concept was presented at the June 6th 2016 meeting in Las Vegas NV and a team of DOE-NE, DOE-EM, and National Laboratory staff discussed the rnerits of each proposal. Discussions among managers and researchers in the weeks following the meeting led to selection of a path forward for phased testing that includes a series of small diarneter borehole tests designed to illuminate thermomechanical processes and potential vapor and brine transport. These tests are intended to be implemented at the WIPP facility and involve collaboration between SNL, LANL, and LBL. This document summarizes the test concepts generated by the te s of researchers and decisions made subsequent to the June 6th meeting.

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Recorded Information Management Records Move Project

Rhodes, Tracy

Throughout the history of Sandia National Laboratories, both federal and corporate records have been stored in 12 structures in remote areas of the lab, none of which are compliant storage facilities under federal regulations. Upon inspection by the National Archives and Records Administration (NARA), findings were levied against Sandia along with recommendations on correcting the issues. The RM Department anticipated over 38,000 boxes of legacy records in Sandia’s current holdings. The current storage areas present an abundance of unknown issues and risks associated with the move project. Along with the large amount of records, and media types, this project faces issues with over 50 years of ever changing filing systems and human error pertaining to data entry, boxes being processed and destroyed. This document presents the final data and results pertaining to the Recorded Information Management Department corrective actions in a well laid out project plan that accommodated safety, security, environmental concerns and of course the records.

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Fukushima Daiichi Radionuclide Inventories

Cardoni, Jeffrey; Jankovsky, Zachary K.

Radionuclide inventories are generated to permit detailed analyses of the Fukushima Daiichi meltdowns. This is necessary information for severe accident calculations, dose calculations, and source term and consequence analyses. Inventories are calculated using SCALE6 and compared to values predicted by international researchers supporting the OECD/NEA's Benchmark Study on the Accident at Fukushima Daiichi Nuclear Power Station (BSAF). Both sets of inventory information are acceptable for best-estimate analyses of the Fukushima reactors. Consistent nuclear information for severe accident codes, including radionuclide class masses and core decay powers, are also derived from the SCALE6 analyses. Key nuclide activity ratios are calculated as functions of burnup and nuclear data in order to explore the utility for nuclear forensics and support future decommissioning efforts.

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Simulation of Optical Phenomena in the Upper Atmosphere

Woods, Mark C.; Sailor, William C.

This SAND report investigates the electron transport equation in the upper atmosphere and how it relates to auroral light emissions. The electron transport problem is a very stiff boundary value problem, so standard numerical methods such as symmetric collocation and shooting methods will not succeed unless if the boundary conditions are altered with unrealistic assumptions. We show this to be unnecessary and demon- strate a method in which the fast and slow modes of the boundary value problem are essentially decoupled. This allows for an upwind finite difference method to be applied to each mode as is appropriate. This greatly reduces the number of points needed in the mesh, and we demonstrate how this eliminates the need to define new boundary conditions. This method can be verified by showing that under certain restrictive as- sumptions, the electron transport equation has an exact solution that can be written as an integral. The connection between electron transport and the aurora is made explicit and a kinetic model for calculating auroral light emissions is given.

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Results 39801–40000 of 99,299
Results 39801–40000 of 99,299