Publications

Results 36001–36200 of 99,299

Search results

Jump to search filters

Thermal Analysis of Disposal of High-Level Nuclear Waste in a Generic Bedded Salt repository using the Semi-Analytical Method

Hadgu, Teklu; Matteo, Edward N.

An example case is presented for testing analytical thermal models. The example case represents thermal analysis of a generic repository in bedded salt at 500 m depth. The analysis is part of the study reported in Matteo et al. (2016). Ambient average ground surface temperature of 15°C, and a natural geothermal gradient of 25°C/km, were assumed to calculate temperature at the near field. For generic salt repository concept crushed salt backfill is assumed. For the semi-analytical analysis crushed salt thermal conductivity of 0.57 W/m-K was used. With time the crushed salt is expected to consolidate into intact salt. In this study a backfill thermal conductivity of 3.2 W/m-K (same as intact) is used for sensitivity analysis. Decay heat data for SRS glass is given in Table 1. The rest of the parameter values are shown below. Results of peak temperatures at the waste package surface are given in Table 2.

More Details
TYPE Other Report YEAR 2017
DOIOSTI

FPGA Authentication Methods

Brotz, Jay K.; Hymel, R.; Punnoose, Ratish J.; Mannos, Tom J.; Grant, Neil; Evans, Neil

One of the greatest challenges facing designers of equipment to be used in a nuclear arms control treaty is how to convince the other party in the treaty to trust its results and functionality. Whether the host provides equipment meant to prove treaty obligations and the inspector needs to gain that trust (commonly referred to as authentication), or the inspector provides this equipment and the host needs to gain this trust (commonly considered to be included in certification), one party generally has higher confidence in the equipment at the start of a treaty regime and the other party needs to gain that confidence prior to use. While we focus on authentication in this document—that is, the inspector gaining confidence in host-provided equipment—our conclusions will likely apply to host certification of inspector-provided equipment.

More Details
TYPE Other Report YEAR 2017
DOIOSTI

Scalability of Several Asynchronous Many-Task Models for In Situ Statistical Analysis

Pebay, Philippe P.; Bennett, Janine C.; Kolla, Hemanth; Borghesi, Giulio

This report is a sequel to [PB16], in which we provided a first progress report on research and development towards a scalable, asynchronous many-task, in situ statistical analysis engine using the Legion runtime system. This earlier work included a prototype implementation of a proposed solution, using a proxy mini-application as a surrogate for a full-scale scientific simulation code. The first scalability studies were conducted with the above on modestly-sized experimental clusters. In contrast, in the current work we have integrated our in situ analysis engines with a full-size scientific application (S3D, using the Legion-SPMD model), and have conducted nu- merical tests on the largest computational platform currently available for DOE science ap- plications. We also provide details regarding the design and development of a light-weight asynchronous collectives library. We describe how this library is utilized within our SPMD- Legion S3D workflow, and compare the data aggregation technique deployed herein to the approach taken within our previous work.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

A Unified Data-Driven Approach for Programming In Situ Analysis and Visualization: An Interim Report of Sandia Sub-Team Contributions

Bennett, Janine C.; Pebay, Philippe P.; Kolla, Hemanth; Borghesi, Giulio

As we look ahead to next generation high performance computing platforms, the placement and movement of data is becoming the key-limiting factor on both performance and energy efficiency. Furthermore, the increased quantities of data the systems are capable of generating, in conjunction with the insufficient rate of improvements in the supporting I/0 infrastructure, is forcing applications away from the off-line post-processing of data towards techniques based on in ,situ analysis and visualization. Together, these challenges are shaping how we will both design and develop effective, performant and energy-efficient software. In particular, the challenges highlight the need for data and data-centric operations to be fundamental in the reasoning about, and optimization of, scientific workflows on extreme-scale architectures.

More Details
TYPE Other Report YEAR 2017
DOIOSTI

Percept User Manual

Carnes, Brian R.; Kennon, Stephen R.

This document is the main user guide for the Sierra/Percept capabilities including the mesh_adapt and mesh_transfer tools. Basic capabilities for uniform mesh refinement (UMR) and mesh transfers are discussed. Examples are used to provide illustration. Future versions of this manual will include more advanced features such as geometry and mesh smoothing. Additionally, all the options for the mesh_adapt code will be described in detail. Capabilities for local adaptivity in the context of offline adaptivity will also be included. This page intentionally left blank.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

Enabling Diverse Software Stacks on Supercomputers using High Performance Virtual Clusters

Younge, Andrew J.; Pedretti, Kevin; Grant, Ryan; Brightwell, Ron

While large-scale simulations have been the hallmark of the High Performance Computing (HPC) community for decades, Large Scale Data Analytics (LSDA) workloads are gaining attention within the scientific community not only as a processing component to large HPC simulations, but also as standalone scientific tools for knowledge discovery. With the path towards Exascale, new HPC runtime systems are also emerging in a way that differs from classical distributed com- puting models. However, system software for such capabilities on the latest extreme-scale DOE supercomputing needs to be enhanced to more appropriately support these types of emerging soft- ware ecosystems. In this paper, we propose the use of Virtual Clusters on advanced supercomputing resources to enable systems to support not only HPC workloads, but also emerging big data stacks. Specifi- cally, we have deployed the KVM hypervisor within Cray's Compute Node Linux on a XC-series supercomputer testbed. We also use libvirt and QEMU to manage and provision VMs directly on compute nodes, leveraging Ethernet-over-Aries network emulation. To our knowledge, this is the first known use of KVM on a true MPP supercomputer. We investigate the overhead our solution using HPC benchmarks, both evaluating single-node performance as well as weak scaling of a 32-node virtual cluster. Overall, we find single node performance of our solution using KVM on a Cray is very efficient with near-native performance. However overhead increases by up to 20% as virtual cluster size increases, due to limitations of the Ethernet-over-Aries bridged network. Furthermore, we deploy Apache Spark with large data analysis workloads in a Virtual Cluster, ef- fectively demonstrating how diverse software ecosystems can be supported by High Performance Virtual Clusters.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

Autonomy and Complexity at Sandia Executive Summary of Academic Alliance Workshop on Autonomy and Complex Systems

Hayden, Nancy K.; Kleban, Stephen

Sandia has identified autonomy as a strategic initiative and an important area for providing national leadership. A key question is, “How might autonomy change how we think about the national security challenges we address and the kinds of solutions we deliver?” Three workshops at Sandia early in 2017 brought together internal stakeholders and potential academic partners in autonomy to address this question. The first focused on programmatic applications and needs. The second explored existing internal capabilities and research and development needs. This report summarizes the outcome of the third workshop, held March 3, 2017 in Albuquerque, NM, which engaged Academic Alliance partners in autonomy efforts at Sandia by discussing research needs and synergistic areas of interest within the complex systems and system modeling domains, and identifying opportunities for partnering on laboratory directed and other joint research opportunities.

More Details
TYPE Other Report YEAR 2017
DOIOSTI

PU-ICE Summary Information

Moore, Michael

The Generator Knowledge Report for the Plutonium Isentropic Compression Experiment Containment Systems (GK Report) provides information for the Plutonium Isentropic Compression Experiment (Pu- ICE) program to support waste management and characterization efforts. Attachment 3-18 presents generator knowledge (GK) information specific to the eighteenth Pu-ICE conducted in August 2015, also known as ‘Shot 18 (Aug 2015) and Pu-ICE Z-2841 (1).’ Shot 18 (Aug 2015) was generated on August 28, 2015 (1). Calculations based on the isotopic content of Shot 18 (Aug 2015) and the measured mass of the containment system demonstrate the post-shot containment system is low-level waste (LLW). Therefore, this containment system will be managed at Sandia National Laboratory/New Mexico (SNL/NM) as LLW. Attachment 3-18 provides documentation of the TRU concentration and documents the concentration of any hazardous constituents.

More Details
TYPE Other Report YEAR 2017
DOIOSTI

Corrosion Monitors for Embedded Evaluation

Robinson, Alex; Pfeifer, Kent B.; Casias, Adrian L.; Howell, Stephen W.; Sorensen, Neil R.; Missert, Nancy

We have developed and characterized novel in-situ corrosion sensors to monitor and quantify the corrosive potential and history of localized environments. Embedded corrosion sensors can provide information to aid health assessments of internal electrical components including connectors, microelectronics, wires, and other susceptible parts. When combined with other data (e.g. temperature and humidity), theory, and computational simulation, the reliability of monitored systems can be predicted with higher fidelity.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

County-Level Climate Uncertainty for Risk Assessments: Volume 25 Appendix X - Forecast Sea Ice Age

Backus, George A.; Lowry, Thomas S.; Jones, Shannon M.; La Jenkins, Tonya N.; Roberts, Barry L.; Malczynski, Leonard A.

This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

County-Level Climate Uncertainty for Risk Assessments: Volume 26 Appendix Y - Historical Ridging Rate

Backus, George A.; Lowry, Thomas S.; Jones, Shannon M.; La Jenkins, Tonya N.; Roberts, Barry L.; Malczynski, Leonard A.

This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

County-Level Climate Uncertainty for Risk Assessments: Volume 9 Appendix H - Forecast Precipitation

Backus, George A.; Lowry, Thomas S.; Jones, Shannon M.; La Jenkins, Tonya N.; Roberts, Barry L.; Malczynski, Leonard A.

This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

County-Level Climate Uncertainty for Risk Assessments: Volume 11, Appendix J - Forecast Evaporation

Backus, George A.; Lowry, Thomas S.; Jones, Shannon M.; La Jenkins, Tonya N.; Roberts, Barry L.; Malczynski, Leonard A.

This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

Installation of Groundwater Monitoring Wells TAV-MW15 and TAV-MW16

Lum, Clinton C.L.

This report documents the installation of two groundwater monitoring wells at the Technical Area V Groundwater (TAVG) Area of Concern at Sandia National Laboratories, New Mexico (SNL/NM). SNL/NM is 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-NA- 0003525. Well installation activities were conducted in accordance with the New Mexico Environment Department (NMED) Hazardous Waste Bureau (HWB)-approved work plan Revised Treatability Study Work Plan for In-Situ Bioremediation at the Technical Area-V Groundwater Area of Concern (Work Plan) (SNL/NM March 2016). The Work Plan was approved by NMED HWB prior to the start of field work (NMED May 2016). Project activities were performed from November 2016 through January 2017 by SNL/NM Environmental Restoration (ER) Operations personnel, and the SNL/NM drilling contractor Cascade Drilling LP. Drilling activities began with borehole drilling and sampling on November 30, 2016. Well construction and development fieldwork was completed on January 31, 2017. Land surveys to establish the location coordinates and elevations of the two wells were completed on March 23, 2017, and transmitted to SNL/NM personnel on April 17, 2017.

More Details
TYPE Other Report YEAR 2017
DOIOSTI

Contingency Contractor Optimization Phase 3 Sustainment Cost by JCA Implementation Guide

Durfee, Justin D.; Frazier, Christopher R.; Arguello, Bryan; Bandlow, Alisa; Gearhart, Jared L.; Jones, Katherine

This document provides implementation guidance for implementing personnel group FTE costs by JCA Tier 1 or 2 categories in the Contingency Contractor Optimization Tool – Engineering Prototype (CCOT-P). CCOT-P currently only allows FTE costs by personnel group to differ by mission. Changes will need to be made to the user interface inputs pages and the database

More Details
TYPE Other Report YEAR 2017
DOIOSTI

Fault Analysis and Detection in Microgrids with High PV Penetration

El Khatib, Mohamed; Hernandez-Alvidrez, Javier; Ellis, Abraham

In this report we focus on analyzing current-controlled PV inverters behaviour under faults in order to develop fault detection schemes for microgrids with high PV penetration. Inverter model suitable for steady state fault studies is presented and the impact of PV inverters on two protection elements is analyzed. The studied protection elements are superimposed quantities based directional element and negative sequence directional element. Additionally, several non-overcurrent fault detection schemes are discussed in this report for microgrids with high PV penetration. A detailed time-domain simulation study is presented to assess the performance of the presented fault detection schemes under different microgrid modes of operation.

More Details
TYPE SAND Report YEAR 2017
DOIOSTI

Impact of Expanded North Slope of Alaska Crude Oil Production on Oil Flows in the Contiguous United States (Summary)

Derosa, Sean; Flanagan, Tatiana P.

Crude oil produced on the North Slope of Alaska (NSA) is primarily transported on the Trans-Alaska Pipeline System (TAPS) to in-state refineries and the Valdez Marine Terminal in southern Alaska. From the Terminal, crude oil is loaded onto tankers and is transported to export markets or to three major locations along the U.S. West Coast: Anacortes-Ferndale area (Washington), San Francisco Bay area, and Los Angeles area. North Slope of Alaska production has decreased about 75% since the 1980s, which has reduced utilization of TAPS.

More Details
TYPE Other Report YEAR 2017
DOIOSTI

Impact of Expanded North Slope of Alaska Crude Oil Production on Crude Oil Flows in the Contiguous United States

Derosa, Sean; Flanagan, Tatiana P.

The National Transportation Fuels Model was used to simulate a hypothetical increase in North Slope of Alaska crude oil production. The results show that the magnitude of production utilized depends in part on the ability of crude oil and refined products infrastructure in the contiguous United States to absorb and adjust to the additional supply. Decisions about expanding North Slope production can use the National Transportation Fuels Model take into account the effects on crude oil flows in the contiguous United States.

More Details
TYPE Other Report YEAR 2017
DOIOSTI
Results 36001–36200 of 99,299
Results 36001–36200 of 99,299