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Cavern leaching at SPR associated with 2017 oil sales and exchanges

Chojnicki, Kirsten

In 2017 small-scale drawdowns at the Strategic Petroleum Reserve (SPR) supported oil sales for the Bipartisan Budget Act of 2015 and the 21st Century Cures Act of 2015 as well as exchanges supporting relief efforts for hurricane Harvey. These drawdowns may affect cavern stability and available drawdowns, thus is important to assess the leaching effects on the cavern shape. Cavern shape estimates from the SANSMIC solution mining code suggest the shapes of 28 caverns were altered in 2017 to varying degrees depending on the total volume of water injected, the initial cavern shape and the distance between the hanging string depth and the oil-brine interface depth. A flaring of the cavern floor occurred in 13 caverns, a geomechanically unfavorable outcome that may require operational changes to preserve cavern integrity. Of the three caverns with post-sale sonars, SANSMIC predictions compared favorably to two but underpredicted the third.

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TYPE SAND Report YEAR 2019
DOIOSTI

Integral Experiment Request 230 CED-2 Summary Report

Harms, Gary A.; Zerkle, Michael L.; Clarity, Justin B.; Heinrichs, David P.

A method is described to test the effect of increased moderation on the 7uPCX critical arrays using the existing assembly hardware. The proposed experiments will allow the exploration of the assembly fuel-to-water ratio out to, and possibly beyond, optimum moderation in the assembly. A significant result reported below is that the total uncertainty in the benchmark keff in some of these experiments is reduced by about a factor of two compared to the uncertainties obtained in the fully-reflected experiments done to date.

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TYPE Other Report YEAR 2019
DOIOSTI

SCEMA: A high channel density electronics module for fast waveform capture

Journal of Instrumentation

Brown, J.; Brubaker, E.; Steele, J.; Nishimura, K.

The development of fast, highly pixelated photodetectors with single-photon sensitivity has the potential to enable a variety of new radiation detection concepts. Systems that desire to employ these detectors without loss of information demand waveform digitization with high sampling rates. Switched capacitor arrays provide a low-cost, low-power, compact solution to fast readout with high channel density. The Sandia Laboratories Compact Electronics for Modular Acquisition (SCEMA) was developed to meet these demands. A single module employs two domino ring sampling switched capacitor arrays (DRS4) [1] to provide 16 channels of up to 5 GS/s waveform digitization. This paper presents an overview of the board design and function. Calibration procedures for the module are discussed. Finally, temporal resolution tests are presented demonstrating the module's viability as readout for high fidelity temporal measurements of single photons in suitable photodetectors.

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TYPE Journal Article YEAR 2019
DOIOSTIScopus

Hardware MPI message matching: Insights into MPI matching behavior to inform design: Hardware MPI message matching

Concurrency and Computation. Practice and Experience

Ferreira, Kurt; Grant, Ryan; Levenhagen, Michael; Levy, Scott L.N.; Groves, Taylor

Here, this paper explores key differences of MPI match lists for several important United States Department of Energy (DOE) applications and proxy applications. This understanding is critical in determining the most promising hardware matching design for any given high-speed network. The results of MPI match list studies for the major open-source MPI implementations, MPICH and Open MPI, are presented, and we modify an MPI simulator, LogGOPSim, to provide match list statistics. These results are discussed in the context of several different potential design approaches to MPI matching–capable hardware. The data illustrate the requirements for different hardware designs in terms of performance and memory capacity. Finally, this paper's contributions are the collection and analysis of data to help inform hardware designers of common MPI requirements and highlight the difficulties in determining these requirements by only examining a single MPI implementation.

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TYPE Journal Article YEAR 2019
DOIOSTI
Results 25001–25100 of 99,299
Results 25001–25100 of 99,299