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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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At least 1,243 records · Page 69
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

Low-Carbon Natural Gas for Transportation: Well-to-Wheels Emissions and Potential Market Assessment in California

This report improves on the understanding of the long-term technology potential of low-carbon natural gas (LCNG) supply pathways by exploring transportation market adoption potential through 2035 in California. Techno-economic assessments of each pathway are developed to compare the capacity, cost, and greenhouse gas (GHG) emissions of select LCNG production pathways. The study analyzes the use of fuel from these pathways in light-, medium-, and heavy-duty vehicle applications. Economic and life-cycle GHG emissions analysis suggest that landfill gas resources are an attractive and relatively abundant resource in terms of cost and GHG reduction potential, followed by waste water treatment plants and biomass with gasification and methanation. Total LCNG production potential is on the order of total natural gas demand anticipated in a success scenario for future natural gas vehicle adoption by 2035 across light-, medium-, and heavy-duty vehicle markets (110 trillion Btu/year).

03 NATURAL GAS↗
DOE OSTI2019

High-Resolution Regional Wave Hindcast for the U.S. Alaska Coast

Regional long-term wave hindcast with state-of-art third-generation models is essential for characterization of regional wave resources. This report summarizes modeling efforts for the simulation of the wave climate along southern Alaska, which used an unstructured, nested-grid modeling approach that incorporates a global-regional nested grid using WAVEWATCH III ® and the high-resolution SWAN (Simulating Waves Nearshore) model. Wave resource and wave bulk parameters were simulated for a 32-year period from 1979 to 2010 and were subsequently validated with wave buoy data in the model domain. Error statistics of model skills were calculated at all buoy stations. Overall, model results, both resource and bulk parameters, match observations well. The model hindcast was able to reproduce the seasonal variation of the sea state with large waves that occur in the winter and early spring months when wind forcing is strong and the calm sea state during the summer when wind forcing is weak. The hindcast also considers the effect of sea ice on wave growth, which affects the southern Bering Sea. The hindcast results, including resource and bulk parameters, were archived at every model grid point for the entire model domain at three-hour intervals. In addition, spectral results were saved at National Data Buoy Center buoy stations and selected virtual buoy locations at hourly intervals. The nested-grid modeling framework employed in this study provides a powerful and efficient modeling approach for accurately simulating wave climate at regional and long-term temporal scales with sufficiently fine resolutions in the nearshore region.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

The Development of Catalysts for Upgrading of Pyrolysis Vapor for Refinery Feedstocks and Intermediates: Cooperative Research and Development, CRADA Number CRD-12-00497 (Final Report)

Fast pyrolysis of biomass with vapor phase upgrading (VPU) can produce refinery feedstocks or intermediates that can meet the Department of Energy’s goal of cost-competitive hydrocarbon fuels by 2017. A key technical barrier for this technology is the lack of selective, cost effective catalysts that can produce high yields of fuel-appropriate hydrocarbons from the pyrolysis vapors. In overcoming this barrier, it will be important to engage leading catalyst development companies to devote their resources and expertise to the development of these materials. Thus, we propose a Cooperative Research and Development Agreement (CRADA) between the National Renewable Energy Laboratory (NREL), a world leader in biomass pyrolysis research and Johnson Matthey (JM), a world leader in the production of advanced catalyst materials to develop and test novel catalysts for efficient VPU. Through its Intercat Inc. subsidiary in Savannah, Ga., Johnson Matthey is internationally recognized as a leader in zeolite-based vapor phase upgrading in refinery duties and an emerging developer of biomass conversion technologies. The research and development efforts described in the proposed work will build upon existing collaborations between NREL and JM and play to the strengths of both institutions. NREL will analyze the composition of pyrolysis vapors as an input to catalyst design, screen and test catalysts, characterize the resulting oil and conduct techno-economic analysis. Catalyst samples will be produced and funded by JM. JM will design and synthesize catalysts, characterize fresh and used catalysts and develop catalyst supports needed to achieve commercially meaningful lifetimes. The project will span catalyst development and testing from the fundamental stage using quantum mechanical modeling and chemical reaction analysis to catalyst screening to integrated pilot studies.

09 BIOMASS FUELS↗
NASA NTRS1973

Terrain type recognition using ERTS-1 MSS images

For the automatic recognition of earth resources from ERTS-1 digital tapes, both multispectral and spatial pattern recognition techniques are important. Recognition of terrain types is based on spatial signatures that become evident by processing small portions of an image through selected algorithms. An investigation of spatial signatures that are applicable to ERTS-1 MSS images is described. Artifacts in the spatial signatures seem to be related to the multispectral scanner. A method for suppressing such artifacts is presented. Finally, results of terrain type recognition for one ERTS-1 image are presented.

Gramenopoulos, N.↗
NASA NTRS1975

Tug fleet and ground operations schedules and controls. Volume 1: Executive summary

This study presents Tug Fleet and Ground Operations Schedules and Controls plan. This plan was developed and optimized out of a combination of individual Tug program phased subplans, special emphasis studies, contingency analyses and sensitivity analyses. The subplans cover the Tug program phases: (1) Tug operational, (2) Interim Upper Stage (IUS)/Tug fleet utilization, (3) and IUS/Tug payload integration, (4) Tug site activation, (5) IUS/Tug transition, (6) Tug acquisition. Resource requirements (facility, GSE, TSE, software, manpower, logistics) are provided in each subplan, as are appropriate Tug processing flows, active and total IUS and Tug fleet requirements, fleet management and Tug payload integration concepts, facility selection recommendations, site activation and IUS to Tug transition requirements. The impact of operational concepts on Tug acquisition is assessed and the impact of operating Tugs out of KSC and WTR is analyzed and presented showing WTR as a delta. Finally, cost estimates for fleet management and ground operations of the DDT&E and operational phases of the Tug program are given.

Source record↗
NASA NTRS1976

LANDSAT follow-on: A report by the applications survey groups. Volume 1: Executive summary

Attempts at operational usage of the LANDSAT imagery by non NASA users are studied with particular emphasis on profitable use of the imagery, as contrasted with investigations concerned with research and development of a technology. An evaluation is given of the functional capabilities of the LANDSAT follow-on and ground systems designs in terms of user requirements and desiderata for data measurements, products, and parameters. Applications survey groups (ASGs) were formed for mineral and petroleum exploration, inland water resources, land inventory, and agriculture. The members were drawn from all segments of the user community: Federal agencies, state and local governments or agencies (or from associations of such constituencies), industry and universities. They were selected so that in aggregate they would be able to adequately assess the state-of-the-art in their technical areas and represent this in the ASG deliberations.

Billingsley, F. C.↗
NASA NTRS1980

Remote sensing in the coastal and marine environment. Proceedings of the US North Atlantic Regional Workshop

Presentations were grouped in the following categories: (1) a technical orientation of Earth resources remote sensing including data sources and processing; (2) a review of the present status of remote sensing technology applicable to the coastal and marine environment; (3) a description of data and information needs of selected coastal and marine activities; and (4) an outline of plans for marine monitoring systems for the east coast and a concept for an east coast remote sensing facility. Also discussed were user needs and remote sensing potentials in the areas of coastal processes and management, commercial and recreational fisheries, and marine physical processes.

Zaitzeff, J. B.↗
NASA NTRS1984

Operational awareness in future space transportation system concepts and technology selections

An analysis of operations for a two-stage, fully reusable future space transportation system has been performed, and the results are discussed. The value of conducting an analysis of operations in the conceptual design phase to produce a highly productive system was demonstrated by obtaining estimated reductions in resources and ground turnaround time and comparing them with estimated mature Shuttle program requirements. Cooperative efforts by users, future vehicle designers, and operations analysts during the conceptual design phase are shown to produce an efficient vehicle design with broad market potential. The synergistic effects of vehicle design configuration, subsystems, and procedures can enhance productivity of the transportation system as measured by flexibility, availability, and viability. Advanced technologies and subsystems beneficial to such a system are identified.

Eide, D. G.↗
NASA NTRS1987

Attention in aviation

The relevance of four principles or mechanisms of human attention to the design of aviation systems and the performance of pilots in multitask environments, including workload prediction and measurement, control-display integration, and the use of voice and head-up displays is discussed. The principles are: the mental energy that supplies task performance (resources), the resulting cross-talk between tasks as they are made more similar (confusion), the combination of different task elements (integration), and the way in which one task is processed and another is ignored (selection or tunneling). The introduction of greater levels of complexity into the validation of attentional theories in order to approach the demands of the cockpit or ATC console is proposed.

Wickens, Christopher D.↗
DOE OSTI2019

Toward Greener and More Sustainable Manufacture of Bauxite-Derived Adsorbents for Water Defluoridation

The bauxite-derived adsorbent, activated alumina (AA), has a current annual global market of over 600 million USD, and of this, more than one-third of AA is used for defluoridation of fluoride-bearing water. The commonly used Bayer process for production of AA suffers from thermodynamic inefficiency, thereby raising costs, and also causes significant environmental damage. Here, we evaluate three other bauxite-derived adsorbents as alternatives to AA for water defluoridation: Mildly processed bauxite, thermally activated bauxite, and acid-treated thermally activated bauxite (ATAB). We first determine the energy intensity and resource efficiency of these three new adsorbents throughout their (future, anticipated) manufacturing processes and compare their defluoridation performance in the laboratory. Then, we quantify the carbon footprints of the three adsorbents via the product life-cycle approach, from their manufacturing to their applications in defluoridation. The results reveal that these three adsorbents exhibit less energy intensity and higher resource efficiency, thereby lowering their carbon footprints by 2-20×, relative to an equivalent amount of AA. We also estimate the operating costs of manufacturing and potential revenues from carbon offsets for each of the three adsorbents. Replacement of about 33 000 tonnes per year of AA currently used for wastewater treatment with equivalent ATAB could annually reduce annual manufacturing costs by 4.7 million USD and additionally generate 79 200 tonnes CO 2 offsets. Finally, this study supports decision-making on selecting a greener and more sustainable approach for wastewater defluoridation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

SPSP Phase III Recruiting, Selecting, and Developing Secure Power Systems Professionals: Individual and Team Performance Guidelines

The pending retirement of significant numbers of power system experts and a continuing trend of increasing complexity in modern power systems prompted the U.S. Department of Energy (DOE) to establish the three-phase Secure Power Systems Professional (SPSP) project. The project developed resources for job definition and competency analysis along with tools to guide assessment and curriculum design and to help identify and develop required knowledge, skills, and abilities in technical and operational aspects of power systems cybersecurity. The Secure Power Systems Professional Phase III final report was released last year which an appendix of Individual and Team Performance Guidelines. This new report is that appendix broken out as a standalone document to assist utilities in recruiting and developing Secure Power Systems Professionals at their site. Individual/Team Performance Guidelines were developed for each of the four job roles: the secure power systems engineer, incident responder, intrusion analyst, and security operator. They enable an “at-a-glance” view of the multidisciplinary and collaborative nature of SPSP job roles, for which skill sets were studied and then mapped to stories of critical incidents or vignettes. This afforded an enumeration of tasks required of each job role to effectively perform responsibilities and to meet bestpractice goals for that operation. Assignment of these tasks among the job roles, either as an individual responsibility or a collaborative responsibility, was validated during a job performance model analysis. The analysis identified 13 master vignettes from the collection of critical incident stories, many of which shared a common set of job responsibilities and tasks that were grouped into four vignette categories according to the task requirement for effective response to each event.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2024

Beyond Capacity Credits: Adaptive Stress Period Planning for Evolving Power Systems

This paper combines and applies concepts from several researchers to outline an alternative framework to plan power systems for resource adequacy needs, which we call Adaptive Stress Period Planning (ASPP). It first provides background information regarding least-cost planning objectives and the challenge of balancing an increasing need for model representation with computational intensity as power systems evolve in complexity. Next, it motivates the opportunity for a new paradigm by outlining challenges of frameworks in use today that rely on aggregate capacity heuristics (i.e., capacity credits and planning reserve margins). Subsequently, it lays out main process details of ASPP, which more directly represents spatial and temporal dynamics of power systems in a capacity expansion model with a process to adaptively select risk periods. The paper concludes with a summary of the approach, its benefits, and opportunities for future work.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2026

Plant-Nitrifier Interactions in Topsoil and Subsoil

Plants can influence soil microbes through resource acquisition and interference competition, with consequences for ecosystem function such as nitrification. However, how plants alter soil conditions to influence nitrifiers and nitrification rates remains poorly understood, especially in the subsoil. Here, coupling the 15N isotopic pool dilution technique, high throughput sequencing and in situ soil O2 monitoring, we investigated how a deep-rooted perennial grass, miscanthus, versus an adjacent shallow-rooted turfgrass reference shapes nitrifier assembly and function along 1 m soil profiles. In topsoil, the suppression of ammonia (NH3) oxidizing archaea (AOA) and gross nitrification rates in miscanthus relative to the reference likely resulted from nitrifiers being outcompeted by plant roots and heterotrophic bacteria for ammonium (NH4+). The stronger tripartite competition under miscanthus may have been caused in part by the lower soil organic matter (SOM) content, which supported lower gross nitrogen (N) mineralization, the major soil process that produces NH4+. In contrast, below 10 cm soil depth, significantly greater gross nitrification rates were observed in miscanthus compared to the reference. This was likely driven by the significantly lower oxygen (O2) in miscanthus than reference subsoil, which selected against aerobic heterotrophic bacteria but in favor of AOA. Overall, we found that plants can regulate AOA community structure and function through different mechanisms in topsoil and subsoil, with suppression of nitrification in topsoil and enhancement of nitrification in subsoil.

Field Data↗
NASA NTRS1972

Selected bibliography on the modeling and control of plant processes

A bibliography of information pertinent to the problem of simulating plants is presented. Detailed simulations of constituent pieces are necessary to justify simple models which may be used for analysis. Thus, this area of study is necessary to support the Earth Resources Program. The report sums up the present state of the problem of simulating vegetation. This area holds the hope of major benefits to mankind through understanding the ecology of a region and in improving agricultural yield.

Viswanathan, M. M.↗
NASA NTRS1985

Selective broadcast interconnection - A novel scheme for fiber-optic local-area networks

A passive, unswitched scheme is introduced for directly interconnecting N stations, each of which has C transmitters and receivers. Implementations using fiber optics with spatial multiplexing and optionally wavelength multiplexing are discussed. This scheme utilizes the same resources as standard topologies with C parallel buses but outperforms them in two respects: (1) the aggregate throughput is proportional to C squared rather than to C; and (2) the power of each transmitter need reach only N/C, instead of N, receivers.

Marhic, M. E.↗
DOE OSTI2015

Life cycle assessment and residue leaching: The importance of parameter, scenario and leaching data selection

Highlights: • Relevance of metal leaching in waste management system LCAs was assessed. • Toxic impacts from leaching could not be disregarded. • Uncertainty of toxicity, due to background activities, determines LCA outcomes. • Parameters such as pH and L/S affect LCA results. • Data modelling consistency and coverage within an LCA are crucial. - Abstract: Residues from industrial processes and waste management systems (WMSs) have been increasingly reutilised, leading to landfilling rate reductions and the optimisation of mineral resource utilisation in society. Life cycle assessment (LCA) is a holistic methodology allowing for the analysis of systems and products and can be applied to waste management systems to identify environmental benefits and critical aspects thereof. From an LCA perspective, residue utilisation provides benefits such as avoiding the production and depletion of primary materials, but it can lead to environmental burdens, due to the potential leaching of toxic substances. In waste LCA studies where residue utilisation is included, leaching has generally been neglected. In this study, municipal solid waste incineration bottom ash (MSWI BA) was used as a case study into three LCA scenarios having different system boundaries. The importance of data quality and parameter selection in the overall LCA results was evaluated, and an innovative method to assess metal transport into the environment was applied, in order to determine emissions to the soil and water compartments for use in an LCA. It was found that toxic impacts as a result of leaching were dominant in systems including only MSWI BA utilisation, while leaching appeared negligible in larger scenarios including the entire waste system. However, leaching could not be disregarded a priori, due to large uncertainties characterising other activities in the scenario (e.g. electricity production). Based on the analysis of relevant parameters relative to leaching, and on general results of the study, recommendations are provided regarding the use of leaching data in LCA studies.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Leaching Behavior of Rare Earth Elements in Fort Union Lignite Coals of North America

Rare earth elements are crucial materials in an incredible array of consumer goods, energy system components and military defense applications. However, the global production and entire value chain for rare earth elements is dominated by China, with the U.S. currently 100% import reliant for these critical materials. Traditional mineral ores including those previously mined in the U.S., however, have several challenges. Chief among these is that the content of the most critical and valuable of the rare earths are deficient, making mining uneconomical. Further, the supply of these most critical rare earths is nearly 100% produced in China from a single resource that is only projected to last another 10 to 20 years. The U.S. currently considers the rare earths market an issue of national security. It is imperative that alternative domestic sources of rare earths be identified and methods developed to produce them. Recently, coal and coal byproducts have been identified as one of these promising alternative resources. This paper details the results of a study on characterization of North Dakota lignite and lignite-related feedstocks as an assessment of their feasibility for rare earth element recovery. The abundance, distribution and modes of occurrence of the rare earth elements in the samples collected were determined in this initial study to inform the selection of appropriate extraction and concentration methods to recover the rare earth elements. Materials investigated include the lignite coals, clay-rich sediments associated with the coal seams, and materials associated with a lignite beneficiation system and power plant. The results show that high rare earth element levels exist both in lignite coals and associated sediments. The form of the rare earth elements in the clay materials is primarily as ultra-fine mineral grains. In the lignite coals, approximately 80-95% of the rare earths content is organically associated, primarily as coordination complexes.

Laudal, Daniel A.↗
DOE OSTI2017

A novel strategy for producing compost with enhanced biopesticide properties through solid-state fermentation of biowaste and inoculation with Bacillus thuringiensis

Highlights: • Bacillus thuringiensis (Bt) growth on non-sterile OFMSW has been demonstrated. • Bt-enriched compost can be produced from non-sterile biowaste. • Non-sterile OFMSW can be valorized through semi-continuous SSF and Bt inoculation. • The self-sustained inoculation procedure proposed will enhance process economics. - Abstract: In the framework of a circular economy, organic solid wastes are considered to be resources useful for obtaining value-added products. Among other potential uses, biodegradable wastes from agricultural, industrial, and domestic sources are being studied to obtain biopesticides through solid-state fermentation (SSF), mainly at the laboratory scale. The suitability of biowaste (source-selected organic fraction of municipal solid waste) for use as a substrate for Bacillus thuringiensis (Bt) growth under non-sterile conditions in a 10 L SSF reactor was determined in this study. An operational strategy for setting up a semi-continuous process yielding a stabilised organic compost-like material enriched with Bt suitable for use as a soil amendment was developed. Concentrations of 1.7·10{sup 7}–2.2·10{sup 7} and 1.3·10{sup 7}–2.1·10{sup 7} CFU g{sup −1} DM for Bt viable cells and spores, respectively, were obtained in the final material. As the results confirmed, Bt-enriched compost-like material with potential biopesticide properties can be produced from non-sterile biowaste.

09 BIOMASS FUELS↗