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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CS4 Central Sands Irrigated Agricultural Field. This is the FLUXNET version of the carbon flux data for the site US-CS4 Central Sands Irrigated Agricultural Field produced by applying the standard ONEFlux (1F) software. Site Description - Heartland Farms Center-Pivot Irrigated Potato Field
This is the AmeriFlux version of the carbon flux data for the site US-CS6 Central Sands Irrigated Agricultural Field. Site Description - Worzella Farms Center-Pivot Irrigated Potato Field
This is the AmeriFlux version of the carbon flux data for the site US-CS8 Central Sands Irrigated Agricultural Field. Site Description - Worzella Farms Center-Pivot Irrigated Potato Field
This is the AmeriFlux version of the carbon flux data for the site US-UTN UFLUX Nephi. Site Description - This tower is located in between 3 agricultural pivots in a rural valley of Utah. It is within 100 meters of SCAN station 2137. Crops include soybeans, corn, and wheat. The tower was installed for a temporary project.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CS5 Central Sands Irrigated Agricultural Field. This is the FLUXNET version of the carbon flux data for the site US-CS5 Central Sands Irrigated Agricultural Field produced by applying the standard ONEFlux (1F) software. Site Description - Heartland Farms Center-Pivot Irrigated Potato Field
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CS6 Central Sands Irrigated Agricultural Field. This is the FLUXNET version of the carbon flux data for the site US-CS6 Central Sands Irrigated Agricultural Field produced by applying the standard ONEFlux (1F) software. Site Description - Worzella Farms Center-Pivot Irrigated Potato Field
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CS8 Central Sands Irrigated Agricultural Field. This is the FLUXNET version of the carbon flux data for the site US-CS8 Central Sands Irrigated Agricultural Field produced by applying the standard ONEFlux (1F) software. Site Description - Worzella Farms Center-Pivot Irrigated Potato Field
This is the AmeriFlux version of the carbon flux data for the site US-UTV UFLUX Desert View. Site Description - This station is located alongside a large pivot that irrigate alfalpha.
This is the AmeriFlux version of the carbon flux data for the site US-UR8 Yellow Jacket - UCRB. Site Description - This site is located in Yellow Jacket, Colorado, on a moderate slope. The area is irrigated using a center pivot system, with alfalfa being the dominant vegetation. The region experiences a temperate climate, characterized by cool to mild temperatures throughout the year and substantial annual precipitation, creating favorable conditions for agricultural activities.
This is the AmeriFlux version of the carbon flux data for the site US-UR1 Boulder - UCRB. Site Description - This site is located in Boulder, Wyoming, in a high-altitude grassland ecosystem. The region experiences cold winters and mild summers, with relatively low precipitation throughout the year. Snowfall is common during the winter months, contributing to the seasonal water availability. The landscape is primarily covered by grass vegetation, with some areas supported by a center pivot irrigation system, which helps sustain plant growth in the dry environment.
This is the AmeriFlux version of the carbon flux data for the site US-UR6 Napi - UCRB. Site Description - This site is located in Farmington, New Mexico, within a flat terrain and irrigated by a center pivot system. The region has a semi-arid climate, with warm summers and mild winters. The area is predominantly covered by alfalfa, which thrives in the irrigated conditions.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-UTV UFLUX Desert View. This is the FLUXNET version of the carbon flux data for the site US-UTV UFLUX Desert View produced by applying the standard ONEFlux (1F) software. Site Description - This station is located alongside a large pivot that irrigate alfalpha.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Ne2 Mead - irrigated maize-soybean rotation site. This is the FLUXNET version of the carbon flux data for the site US-Ne2 Mead - irrigated maize-soybean rotation site produced by applying the standard ONEFlux (1F) software. Site Description - The study site is one of three fields (all located within 1.6 km of each other) at the University of Nebraska Eastern Nebraska Research, Extension and Education Center near Mead, Nebraska. This site is irrigated with a center pivot system. Prior to the initiation of the study, the irrigated site had a 10-yr history of maize-soybean rotation under no-till management. A tillage operation (disking) was done just prior to the 2001 planting to homogenize the top 0.1 m of soil, incorporate P and K fertilizers, as well as previously accumulated surface residues. Since this tillage operation, the site has been under no-till management in a maize-soybean rotation (maize odd years and soybean even years). There was a brief period due to an intercomparison study from 2010 to 2013 when fall conservation tillage was performed and maize (not soybean) was planted in 2010 and 2012. The management reverted to a strictly no-till maize-soybean crop rotation after 2014.
Cross-correlation techniques have played a long-standing and pivotal role in seismic event monitoring. However, the performance of correlation-based detectors is challenged by nuisance seismicity, or nontarget signals. Such detections are a problem when the mission is to automatically map events to the correct source region. Using aftershocks of the 2014 $M_w$ 6.0 South Napa, California, earthquake, we demonstrate the effectiveness of utilizing a dynamic correlation processor framework in a generalized likelihood ratio test (GLRT) detector configuration to minimize nontarget detections. A GLRT maximizes a detection statistic with respect to one or more unknown parameters. In this case, the detection statistic is a template signal match against the waveform in a window sliding over a data stream, and the unknown parameter is an index variable indicating group membership of the template event or events. Detected events are assigned to the event group that yields the largest detection statistic. In this work, our results show that a GLRT detector will outperform a suite of independently operating correlation and subspace detectors in terms of having a lower nontarget detection rate at a given missed detection rate. We also show that a GLRT detector composed of a few high-rank subspace detectors has a slightly higher nontarget detection rate, but a significantly lower missed detection rate, than a GLRT detector composed of many low-rank subspace detectors. The high-rank GLRT configuration produced impressive results even with marginal data (single channel, single station, and very low time bandwidth product), which bodes well for the utility of building efficient aftershock classification systems and global monitoring systems at larger scales. However, future work is required to assess performance at the regional scale and to assess the performance of the system at detecting target events not used in the detector template creation.
PIP-II is an 800 MeV superconducting RF linac under development at Fermilab. As the new first stage in our accelerator chain, it will deliver high-power beam to multiple experiments simultaneously and thus drive Fermilab’s particle physics program for years to come. In a pivot for Fermilab, controls for PIP-II are based on EPICS instead of ACNET, the legacy control system for accelerators at the lab. This paper discusses the status of the EPICS controls work for PIP-II. We describe the EPICS tools selected for our system and the experience of operators new to EPICS. We introduce our continuous integration / continuous development environment. We also describe some efforts at cooperation between EPICS and ACNET, or efforts to move towards a unified interface that can apply to both control systems.
The implementation of High Pressure Rinse (HPR) not only ensures thorough cleaning of the inner high purity niobium surface of Superconducting Radio Frequency (SRF) cavities but also unlocks their full potential for achieving peak performance. By effectively removing contaminants and impurities, HPR sets the stage for enhanced superconducting properties, improved energy efficiency, and superior operational stability. A simulation tool has been developed, facilitating the accurate prediction of both the quality and effectiveness of the rinsing process before its execution in the cleanroom. This tool, the focus of this paper, stands as a pivotal advancement in optimizing Superconducting Radio Frequency (SRF) cavity preparation. Furthermore, our paper will also present correlations with cavity cold testing results, demonstrating the practical applicability and reliability of the simulation predictions in real-world scenarios.
Electrification of transport and other energy intensive activities is of growing importance as it provides an underpinning method to reduce carbon emissions. With an increase in reliance on renewable sources of energy and a reduction in the use of more predictable fossil fuels in both stationary and mobile applications, energy storage will play a pivotal role and batteries are currently the most widely adopted and versatile form. Therefore, understanding how batteries work, how they degrade, and how to optimize and manage their operation at large scales is critical to achieving emission reduction targets. The electric vehicle (EV) industry requires a considerable number of batteries even for a single vehicle, sometimes numbering in the thousands if smaller cells are used, and the dynamics and degradation of these systems, as well as large stationary power systems, is not that well understood. As increases in the efficiency of a single battery become diminishing for standard commercially available chemistries, gains made at the system level become more important and can potentially be realised more quickly compared with developing new chemistries. Mathematical models and simulations provide a way to address these challenging questions and can aid the engineer and designers of batteries and battery management systems to provide longer lasting and more efficient energy storage systems.
Mineral formation from ions in aqueous solutions begins with complex initial stages, where amorphous and liquid-like precursors play pivotal roles before crystalline growth occurs. Both classical and non-classical nucleation and growth theories, introduced in previous chapters, offer explanations, each with their own strengths and limitations, for the complex intermediate phases observed in experimental research. Analytical techniques play a critical role in detecting and characterizing precursor phases, offering valuable insights into nucleation and growth mechanisms across various temporal and spatial scales. In conclusion, molecular dynamics and modelling provide in-depth perspectives on these phases, allowing for a closer examination of their nucleation and growth mechanisms at the molecular level, and revealing the intricate processes that govern their behaviour.