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How reduced vacuum pumping capability in a coating chamber affects the laser damage resistance of HfO2/SiO2 antireflection and high reflection coatings

Proceedings of SPIE - The International Society for Optical Engineering

Field, Ella; Bellum, John C.; Kletecka, Damon

Optical coatings with the highest laser damage thresholds rely on clean conditions in the vacuum chamber during the coating deposition process. A low base pressure in the coating chamber, as well as the ability of the vacuum system to maintain the required pressure during deposition, are important aspects of limiting the amount of defects in an optical coating that could induce laser damage. Our large optics coating chamber at Sandia National Laboratories normally relies on three cryo pumps to maintain low pressures for e-beam coating processes. However, on occasion, one or more of the cryo pumps have been out of commission. In light of this circumstance, we explored how deposition under compromised vacuum conditions resulting from the use of only one or two cryo pumps affects the laser-induced damage thresholds of optical coatings. Finally, the coatings of this study consist of HfO2 and SiO2 layer materials and include antireflection coatings for 527 nm at normal incidence, and high reflection coatings for 527 nm, 45⁰ angle of incidence (AOI), in P-polarization (P-pol).

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A Photovoltaic System Payback Calculator

Riley, Daniel; Fleming, Jeffrey; Gallegos, Gerald R.

The Roof Asset Management Program (RAMP) is a DOE NNSA initiative to manage roof repairs and replacement at NNSA facilities. In some cases, installation of a photovoltaic system on new roofs may be possible and desired for financial reasons and to meet federal renewable energy goals. One method to quantify the financial benefits of PV systems is the payback period, or the length of time required for a PV system to generate energy value equivalent to the system's cost. Sandia Laboratories created a simple spreadsheet-based solar energy valuation tool for use by RAMP personnel to quickly evaluate the estimated payback period of prospective or installed photovoltaic systems.

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Simulation of Photovoltaic Power Output for Solar Integration Studies in the Southeast US

Hansen, Clifford; Martin, Curtis

We describe the method used to simulate one year of AC power at one-minute intervals for a large collection of hypothetical utility-scale photovoltaic plants of varying size, employing either fixed-tilt PV modules or single-axis tracking, and for distribution-connected photovoltaic (DPV) power systems assumed for a number of metropolitan areas. We also describe the simulation of an accompanying day-ahead forecast of hourly AC power for utility-scale plants and DPV systems such that forecast errors are consistent with errors reported for current forecasting methods. The results of these simulations are intended for use in a study that examines the possible effects of increased levels of photovoltaic (PV) generation bulk on power variability within the Tennessee Valley Authority (TVA) and Southern Company service territories.

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Contingency Contractor Optimization Phase 3 Sustainment Platform Requirements - Contingency Contractor Optimization Tool - Prototype

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

Sandia National Laboratories (Sandia) is in Phase 3 Sustainment of development of a prototype tool, currently referred to as the Contingency Contractor Optimization Tool - Prototype (CCOTP), under the direction of OSD Program Support. CCOT-P is intended to help provide senior Department of Defense (DoD) leaders with comprehensive insight into the global availability, readiness and capabilities of the Total Force Mix. The CCOT-P will allow senior decision makers to quickly and accurately assess the impacts, risks and mitigating strategies for proposed changes to force/capabilities assignments, apportionments and allocations options, focusing specifically on contingency contractor planning. During Phase 2 of the program, conducted during fiscal year 2012, Sandia developed an electronic storyboard prototype of the Contingency Contractor Optimization Tool that can be used for communication with senior decision makers and other Operational Contract Support (OCS) stakeholders. Phase 3 used feedback from demonstrations of the electronic storyboard prototype to develop an engineering prototype for planners to evaluate. Sandia worked with the DoD and Joint Chiefs of Staff strategic planning community to get feedback and input to ensure that the engineering prototype was developed to closely align with future planning needs. The intended deployment environment was also a key consideration as this prototype was developed. Initial release of the engineering prototype was done on servers at Sandia in the middle of Phase 3. In 2013, the tool was installed on a production pilot server managed by the OUSD(AT&L) eBusiness Center. The purpose of this document is to specify the CCOT-P engineering prototype platform requirements as of May 2016. Sandia developed the CCOT-P engineering prototype using common technologies to minimize the likelihood of deployment issues. CCOT-P engineering prototype was architected and designed to be as independent as possible of the major deployment components such as the server hardware, the server operating system, the database, and the web server. This document describes the platform requirements, the architecture, and the implementation details of the CCOT-P engineering prototype.

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Enabling Technologies for Ultra-Safe and Secure Modular Nuclear Energy

Mendez, Carmen M.; Rochau, Gary E.; Middleton, Bobby D.; Rodriguez, Salvador B.; Rodriguez, Carmelo; Schleicher, Robert

Sandia National Laboratories and General Atomics are pleased to respond to the Advanced Research Projects Agency-Energy (ARPA-e)’s request for information on innovative developments that may overcome various current reactor-technology limitations. The RFI is particularly interested in innovations that enable ultra-safe and secure modular nuclear energy systems. Our response addresses the specific features for reactor designs called out in the RFI, including a brief assessment of the current state of the technologies that would enable each feature and the methods by which they could be best incorporated into a reactor design.

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Energy Storage System Guide for Compliance with Safety Codes and Standards

Conover, David R.; Cole, Pam C.

Codes, standards and regulations (CSR) governing the design, construction, installation, commissioning and operation of the built environment are intended to protect the public health, safety and welfare. While these documents change over time to address new technology and new safety challenges there is generally some lag time between the introduction of a technology into the market and the time it is specifically covered in model codes and standards developed in the voluntary sector. After their development, there is also a timeframe of at least a year or two until they are adopted. Until existing model codes and standards are updated or new ones developed and then adopted, one seeking to deploy energy storage technologies or needing to verify an installation’s safety may be challenged in applying current CSRs to an energy storage system (ESS).

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Conducting a Nuclear Security Assessment

Leach, Janice; Snell, Mark K.

There are three general steps that make up a nuclear security assessment: 1. Develop data Libraries that indicate how effective the physical protection measures are both individually but also as parts of subsystems and actual systems. 2. Perform Path Analysis 3. Perform Scenario Analysis. Depending upon the nature and objectives of the assessment not all three of these steps may need to be performed; for example, at facilities with simple layouts there may not be a need to perform path analysis. Each of these steps is described within this report.

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An investigation of DTOcean foundation and anchor systems

Gomez, Steven P.; Jensen, Richard P.; Heath, Jason E.

This memo documents the mechanical loading analysis performed to date for the DTOcean program WP4 foundation and anchor systems submodule. FEA simulations were performed to validate design requirements defined by Python based analytic simulations of the WP4 program Naval Facilities Engineering Command (NAVFAC) tool. This FEA procedure focuses on worst case loading scenarios on direct mbedment anchor and suction caisson designs produced by WP4. These models include a steel casing and steel anchor with soft clay and dense sand surrounding the steel components respectively.

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Ganged Heliostat Modal Memo

Moya, Adam

This memo documents the methodology and results from the modal tests conducted on the ganged heliostat prototype in April of 2016. Modal tests were conducted on the ganged heliostat prototype constructed at the National Solar Thermal Test Facility (NSTTF) to describe the structures dynamics and examine how the first few modes of vibration may be excited during wind events. This memo documents the experimental test setup and results including natural frequencies and damping estimates for each test conducted along with some preliminary wind excitation analysis.

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Results 43401–43600 of 100,993
Results 43401–43600 of 100,993
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