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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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In October 2019, reports emerged that the Trump administration was considering a withdrawal from the Open Skies Treaty. According to media sources, President Trump has already signed a memorandum to leave the treaty, but the United States has not yet officially initiated the six-month withdrawal process. This article discusses 5 reasons why the U.S. should not withdraw.
Embodiments provide a system and method for reasoning about the optimality of a configuration parameter of a distributed system. During operation, the system obtains a multi-layer graph for a system with a plurality of components, wherein the multi-layer graph comprises a configuration subgraph, a vulnerability subgraph, and a dependency subgraph. The system determines, based on the multi-layer graph, constraint relationships associated with configuration parameters for the components, wherein the constraint relationships include security constraints and functionality constraints. The system computes an unsatisfiable core which comprises a set of mutually incompatible constraints. The system resolves, based on a strategy and over multiple iterations, the unsatisfiable core by analyzing one pair of mutually incompatible constraints per a respective iteration, to obtain a new unsatisfiable core which comprises a smaller number of mutually incompatible constraints than the computed unsatisfiable core or a previously computed unsatisfiable core from a most recent iteration.
Report provides recommendations and best practices concerning fair and reasonable price determination in federal energy performance contracts (EPCs), which include energy savings performance contracts (ESPCs) and utility energy service contracts (UESCs). It reflects the experiences, lessons learned, and best practices of agencies implementing EPCs, and is consistent with FEMP’s training on this subject. This is an update to the 2015 revision.
This white paper identifies the following recommendations for states as they consider issues related to electric vehicle supply equipment program income under the National Electric Vehicle Infrastructure program and other programs covered by National Electric Vehicle Infrastructure Standards and Requirements in the U.S. Code of Federal Regulations (23 CFR 680): 1. Conduct value analysis for better outcomes 2. Promote pricing transparency
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Throughout the world, especially in dense urban environments, the quality of life is being negatively impacted by ever growing commute time. Travel, beyond commuting, is increasingly driven by door-to-door challenges ? not just gate-to-gate considerations. Air Mobility may be an approach to address these challenges, as it can effectively convert our 2D mobility system to a 3D mobility system, vastly increasing mobility options.
As the volume of text-based Earth science research grows, it is increasingly possible to discover latent relationships in the literature. However, traditional methodologies are restricted by limited computational capabilities and intractable problem spaces. Advancements in natural language processing (NLP) have allowed us to use an extensive Earth science corpus to create a domain-specific word vector model, Es2Vec, which we have used to surface latent relationships between Earth science concepts and generate improved keyword tags. Earth science metadata keyword assignment is a challenging problem. Dataset curators select appropriate keywords from the Global Change Master Directory (GCMD) set of keywords. The keywords an are integral part of the search and discovery of these datasets. Hence, the selection of keywords is crucial to increasing the discoverability of datasets. Utilizing machine learning techniques, we provide users with automated keyword suggestions to complement manual selection. We trained a machine learning model that leverages the semantic embedding ability of Word2Vec models to process abstracts and suggest relevant keywords. A user interface tool we built to assist data curators in the assignment of such keywords is also described.
DRF helps realize the full potential of future air mobility to advance human society. This information discovery and exchange ecosystem enables the transportation of people and cargo to places previously not served or underserved by aviation.
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Provides three themes where DRF can support wildfire opportunities.
Eric Isaacs, director of Argonne National Laboratory and a physicist by training, spoke to recipients of the U.S. Department of Energy Office of Science Graduate Fellowships. Among the topics: Why choose a career in science and tech? More info on the fellowships, which are offered every year: http://scgf.orau.gov/index.html August 9, 2010
In current nuclear power plants (NPPs) a large amount of condition-based data which can be used to assess and monitor component health and performance. Assessing component health from such data can be performed with a large variety of methods. While the analysis of numeric data can be performed with several methods, the extraction of information from textual data remains a challenge. Currently employed natural language processing (NLP) methods do not really provide quantitative information that might be contained in IRs. In addition, the integration of numeric and textual data to identify possible causal relationships between data elements is still an unresolved challenge. This paper presents an approach to extract information from textual (e.g., incident or maintenance reports) and numeric data that relies on model based system engineer (MBSE) models. MBSE are diagrams designed to represent system and component dependencies (from both a form and functional point of view). In our approach, MBSE models emulate system engineer knowledge about component/system architecture. NLP methods are employed to perform syntactic and semantic analyses. Syntactic analysis analyzes the grammatical structure of a sentence while semantic analysis is designed to analyze the logic structure of a sentence. An innovative element of our approach is that semantic analysis uses MBSE models to identify links between textual elements. Similarly, numeric data is directly linked to elements of the MBSE models in order to map which functions are being monitored.
Abstract not provided.
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Plasma Focus (PF) devices as well as other similar pulsed discharge devices requires a variety of diagnostics for their proper control and optimization, including the voltage between electrodes, the time derivative of the discharge current, detection of X-rays and neutron emissions, and pulsed laser images (Shadow, Schlieren, interferograms). This article discusses the problem of the time reference of all these outputs and proposes specific techniques for synchronizing them based on sound physical grounds. The foundations of synchronization criterion are verified in several experiments on PF devices.
In this research work, cost-effective structural material synthesis routes have been adopted in the form of thermal cycling designed and applied on a low-cost material (AISI 1010 steel). The main synthesis route consists of two-step thermal cycling (designed with respect to iron–carbon phase diagram) combining short-duration holding in upper critical and intercritical temperature regimes and different cooling conditions (forced air cooling and ice-brine quenching). Accordingly, the adopted hierarchical design approach (from nanoscale onwards) with a combination of hard and soft phases (to attain an adequate balance between mutually exclusive strength and ductility properties) results in origin of a novel microstructure. The microstructure consists of dislocation-enriched martensite regions (possessing plate and lath morphologies in 1:4 ratio) containing nanosized cementite particles and α-ferrite regions containing submicroscopic cementite particles. As a consequence, an excellent combination of strength (UTS = 905 MPa) and ductility (%Elongation = 17) is achieved in the synthesized material.