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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 1,297 records · Page 72
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

A New Multi-Scale State Estimation Framework for the Next Generation of Power Grid EMS

Accurate system state information under various operation conditions is a prerequisite for power grid monitoring and efficient control. To achieve that goal, a new multi-scale state estimation framework is proposed, paving the way for the development of next generation of energy management system (EMS). The developed framework consists of three key components, namely the static state estimation (SSE) module, the dynamic state estimation (DSE) module, the interfaces and switching logics between the two modules. Specifically, the singular spectrum analysis (SSA)-based change point detection approach is developed to monitor the system continuously. If no event is detected by the SSA, the robust SSE using both SCADA and PMU measurements is executed. Otherwise, the event is declared and the results from SSE are used to derive the initial condition for DSE. During the transient process, only PMU-based DSE is executed for system monitoring and it will be terminated when SSA does not detect any change point of the system. After that, the DSE results are forwarded for SSE initialization and bus voltage magnitude and angle estimations. Simulation results carried out on the IEEE 39-bus system demonstrate the effectiveness and benefits of the proposed framework.

Power system state estimation, energy management s↗
DOE OSTI2014

Controlling Hexavalent Americium – A Centerpiece to a Compact Nuclear Fuel Cycle

Closing the nuclear fuel cycle could be simplified by recovering the actinides U through Am as a group. This could be achieved by converting U, Np, Pu and Am to the hexavalent state. Uranium, Np and Pu are readily oxidized to the hexavalent state. Generation of hexavalent Am in acidic solutions is more difficult, as the standard reduction potential of the Am(VI) /Am(III) couple (+1.68 V in 1 M HClO4) is well outside of the electrochemical stability window of water. While the oxidation and separation of Am has been demonstrated under laboratory conditions, several issues could plague scale up and implementation of this separation with used fuel. Two primary concerns are considered. The first issue concerns the stability of the oxidized Am. The second involves the undesirable co-extraction of tetravalent f-elements with the hexavalent actinides. To address the first concern regarding Am redox instability, Am reduction will be monitored under a variety of different conditions to establish the means of improving the stability of Am(VI) in the organic phase. Identifying the components contributing most significantly to its reduction will allow thoughtful modification of the process. To address the second concern, we propose to apply branched chain extractants to separate hexavalent actinides from tetravalent f-elements. Both branched monoamide and organophosphorus extractants have demonstrated significant selectivity for UO22+ versus Th4+, with separation factors generally on the order of 100. The efforts of this two-pronged research program should represent a significant step forward in the development of aqueous separations approaches designed to recover the U-Am actinides based on the availability of the hexavalent oxidation state. For the purposes of this proposal, separations based on this approach will be called SAn(VI) separations, indicating the Separation of An(VI).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2016

Assessing Cumulative Impacts from Source Units within Hanford's Inner Area - 16546

The Central Plateau area at the Hanford Site has a complex mix of waste sites in several operable units, with many co-mingled source contamination and groundwater plumes. A key component of the evaluation process involves a planned assessment of the potential cumulative impacts resulting from co-mingled plumes and potential contribution from waste sites sources throughout the Inner Area, about 26 million square meters (10 square miles) area located in the middle of the Central Plateau. This assessment will evaluate the fate and transport of contamination at each waste site and remedial actions at those waste sites, providing an integrated vadose zone and groundwater fate and transport assessment. Although DOE's goal is to remediate the entire Inner Area to meet standard requirements in the National Contingency Plan (NCP), the complexity of the contamination including continuing contaminant sources in the Inner Area may not allow restoration of groundwater in a reasonable timeframe. DOE and regulatory agencies may need to evaluate the technical practicability of remedial actions and the potential for establishment of one or more waste management areas where drinking water standards can be obtained and maintained. The cumulative impacts evaluation is the tool to evaluate remedial action effects across source and groundwater operable units, contribute to technical impracticability evaluations, support remedial design and remedial process optimization efforts, identify additional monitoring requirements, and evaluate standard and conditional points of compliance for use considering all contaminant sources and groundwater plumes. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1981

Requirements of space-borne microwave radiometers for detecting soil moisture contents

A multilayer radiative transfer model for predicting the relationship between soil moisture content and microwave emission is summarized. Attention is also given to the performance of various microwave sensors for soil moisture retrieval; here, the requirements of a satellite sensor system for monitoring large-scale soil moisture conditions are discussed. These requirements are presented in terms of (1) the wavelength, (2) atmospheric contamination, (3) polarization, (4) frequency of observation, and (5) spatial resolution. Each parameter is discussed in terms of microwave response. Previous aircraft data with extensive ground truth information are used to support the theories proposed. Trade-offs between the parameters and an optimum sensor system for space monitoring soil moisture information are discussed.

Burke, H.-H. K.↗
DOE OSTI2021

Structures including a measurement coating and methods of forming the same

A structure includes a substrate and a coating applied over the substrate, the coating containing particles sized between 30 and 250 micrometers. A proportion of the particles to the carrier is between 40 and 70 by volume percentage. In response to excitation of the structure by a controllable excitation source, a first instrument monitors behavior of the particles to determine a first condition of the structure thereby. In response to an absence of excitation of the structure by the controllable excitation source, a second instrument monitors behavior of the particles to determine a second condition of the structure thereby.

Ely, George Ray↗
DOE OSTI2014

FutureGen 2.0 Monitoring Program: An Overview of the Monitoring Approach and Technologies Selected for Implementation

The FutureGen 2.0 Project will design and build a first-of-its-kind, near-zero emissions coal-fueled power plant with carbon capture and storage (CCS). To assess storage site performance and meet the regulatory requirements of the Class VI Underground Injection Control (UIC) Program for CO2 Geologic Sequestration, the FutureGen 2.0 project will implement a suite of monitoring technologies designed to 1) evaluate CO2 mass balance and 2) detect any unforeseen loss in CO2 containment. The monitoring program will include direct monitoring of the injection stream and reservoir, and early-leak-detection monitoring directly above the primary confining zone. It will also implement an adaptive monitoring strategy whereby monitoring results are continually evaluated and the monitoring network is modified as required, including the option to drill additional wells in out-years. Wells will be monitored for changes in CO2 concentration and formation pressure, and other geochemical/isotopic signatures that provide indication of CO2 or brine leakage. Indirect geophysical monitoring technologies that were selected for implementation include passive seismic, integrated surface deformation, time-lapse gravity, and pulsed neutron capture logging. Near-surface monitoring approaches that have been initiated include surficial aquifer and surface- water monitoring, soil-gas monitoring, atmospheric monitoring, and hyperspectral data acquisition for assessment of vegetation conditions. Initially, only the collection of baseline data sets is planned; the need for additional near- surface monitoring will be continually evaluated throughout the design and operational phases of the project, and selected approaches may be reinstituted if conditions warrant. Given the current conceptual understanding of the subsurface environment, early and appreciable impacts to near-surface environments are not expected.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Split-pane electrochromic window control based on an embedded photometric device with real-time daylighting computing

Well-designed electrochromic (EC) glazing control can improve the energy performance of buildings and visual comfort of occupants in highly glazed buildings. Here in this paper, we designed and demonstrated a compact integrated EC glazing automation system to control tint states of a split-pane EC window according to variations of sky conditions. The control is based on monitoring the luminance distribution of the sky and real-time lighting computation for a building interior, using an embedded photometric device (EPD). It optimizes tint states of EC glazing to offer sufficient daylight provision and temper discomfort glare for occupants, which potentially mitigates excessive solar heat gain. ’In-situ’ experiments were conducted in a full-scale testbed to demonstrate the daylighting performance under various sky conditions. Finally, experimental results showed 83% of the working time for work-plane illuminance (WPI) and 95% of the time for daylight glare probability (DGP) were constrained in comfort range (WPIϵ[500, 2000] lux, DGP ≤ 0.35) by the automated EC glazing (controlled by EPD) under clear skies; 68% of the time for WPI and 94% of the time for DGP in confined range under clear skies with thin clouds; 62% of the time for WPI and 85% of the time for DGP in confined range under partly cloudy skies.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2013

Real-time monitoring of high-gravity corn mash fermentation using in situ raman spectroscopy

In situ Raman spectroscopy was employed for real-time monitoring of simultaneous saccharification and fermentation (SSF) of corn mash by an industrial strain of Saccharomyces cerevisiae. An accurate univariate calibration model for ethanol was developed based on the very strong 883 cm -1 C-C stretching band. Multivariate partial least squares (PLS) calibration models for total starch, dextrins, maltotriose, maltose, glucose, and ethanol were developed using data from eight batch fermentations and validated using predictions for a separate batch. The starch, ethanol, and dextrins models showed significant prediction improvement when the calibration data were divided into separate high- and low-concentration sets. Collinearity between the ethanol and starch models was avoided by excluding regions containing strong ethanol peaks from the starch model and, conversely, excluding regions containing strong saccharide peaks from the ethanol model. The two-set calibration models for starch (R 2 = 0.998, percent error = 2.5%) and ethanol (R 2 = 0.999, percent error = 2.1%) provide more accurate predictions than any previously published spectroscopic models. Glucose, maltose, and maltotriose are modeled to accuracy comparable to previous work on less complex fermentation processes. Our results demonstrate that Raman spectroscopy is capable of real time in situ monitoring of a complex industrial biomass fermentation. To our knowledge, this is the first PLS-based chemometric modeling of corn mash fermentation under typical industrial conditions, and the first Raman-based monitoring of a fermentation process with glucose, oligosaccharides and polysaccharides present.

biofuels↗
NASA NTRS2002

Demonstrating Acquisition of Real-Time Thermal Data over Fires Utilizing UAVs

NASA-Ames Research Center, in collaboration with General Atomics Aeronautical Systems, Inc. has been developing real-time data acquisition and information delivery systems employing uninhabited aerial vehicle (UAV) technology for disaster mitigation and assessment demonstrations. Working in conjunction with the US Forest Service, a disaster community agency responsible for wildfire management and mitigation, we developed a large-scale wildfire demonstration called the First Response Experiment (FIRE). During that experiment in late summer 2001, the participants demonstrated the melding of innovative technologies such as UAV platforms, real-time data processing, and data telemetry for quick analysis of a disaster event. The General Atomics ALTUS UAV, the Airborne Infrared Disaster Assessment System (AIRDAS) and Over-The-Horizon (OTH) satellite data telemetry equipment were employed over a controlled burn to test the feasibility of a disaster monitoring and mitigation platform for hazardous duty. The ALTUS UAV was employed to demonstrate the long duration, altitude, and payload capability of unmanned platforms for acquiring disaster related data. The ALTUS has an operational altitude to 45,000 feet (13,700 in), with a flight duration of twenty-four hours and a payload capacity of over 300 lbs. (148.5 kg). This allows the platform to operate under the conditions that would be necessary for monitoring and mitigating disaster events throughout the Unites States. The four channel AIRDAS data (calibrated thermal infrared digital imagery of the fire event) was sent from the ALTUS UAV via a satellite communications system (NERA transponder and INMARSAT satellite) to a data archive server and an image processing work station at NASA-Ames Research Center, 400 miles away.

Wegener, Steven S.↗
DOE OSTI2016

Circadian rhythms have significant effects on leaf-to-canopy scale gas exchange under field conditions

Background Molecular clocks drive oscillations in leaf photosynthesis, stomatal conductance, and other cell and leaf-level processes over ~24 h under controlled laboratory conditions. The influence of such circadian regulation over whole-canopy fluxes remains uncertain; diurnal CO 2 and H 2 O vapor flux dynamics in the field are currently interpreted as resulting almost exclusively from direct physiological responses to variations in light, temperature and other environmental factors. We tested whether circadian regulation would affect plant and canopy gas exchange at the Montpellier European Ecotron. Canopy and leaf-level fluxes were constantly monitored under field-like environmental conditions, and under constant environmental conditions (no variation in temperature, radiation, or other environmental cues). Results We show direct experimental evidence at canopy scales of the circadian regulation of daytime gas exchange: 20–79 % of the daily variation range in CO 2 and H 2 O fluxes occurred under circadian entrainment in canopies of an annual herb (bean) and of a perennial shrub (cotton). We also observed that considering circadian regulation improved performance by 8–17 % in commonly used stomatal conductance models. Conclusions Our results show that circadian controls affect diurnal CO 2 and H 2 O flux patterns in entire canopies in field-like conditions, and its consideration significantly improves model performance. Lastly, circadian controls act as a ‘memory’ of the past conditions experienced by the plant, which synchronizes metabolism across entire plant canopies.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Aniak Energy Action Plan

In 2017, the Native Village of Aniak received a grant for the Aniak Energy Efficiency Project from the United States Department of Energy Office of Indian Energy policy and programs. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Aniak and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the seven project buildings as well as the Aniak Traditional Council’s goals for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Aniak Energy Efficiency Project, but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Aniak for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Kwigillingok Energy Action Plan

In 2017, the Native Village of Kwigillingok received a grant for the Kwigillingok Energy Efficiency Project from the United States Department of Energy Office of Indian Energy. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Kwigillingok and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the six project buildings as well as the I.R.A. Council’s goal for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project, which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Kwigillingok Energy Efficiency Project but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Kwigillingok for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Atmautluak Energy Action Plan

In 2017, the Native Village of Atmautluak received a grant for the Atmautluak Energy Efficiency Project from the United States Department of Energy Office of Indian Energy. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Atmautluak and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the six project buildings as well as the Traditional Council’s goal for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Atmautluak Energy Efficiency Project, but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Atmautluak for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Akiachak Energy Action Plan

In 2017, the Akiachak Native Community received a grant for the Akiachak Energy Efficiency Project from the United States Department of Energy Office of Indian Energy. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Akiachak and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the nine project buildings as well as the I.R.A. Council’s goal for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Akiachak Energy Efficiency Project, but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Akiachak for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2016

Developing a Scalable System for Biorecovery of Critical Materials from Industrial Waste with Gluconobacter Oxydans

Organic acid production by Gluconobacter oxydans has been proposed as part of a potential economical and environmentally friendly heterotrophic bioleaching process for recovery of rare earth elements from industrial waste. To provide organic acids in a quantity and at a rate useful for commercial bioleaching, continuous culture of the acid-producing organism will be necessary. The objective of this research project was to determine optimal conditions for continuous cultivation of G. oxydans for production of organic acids. Cultures were subjected to dilution rates ranging from .05 hr -1 to .38 hr -1 to determine the optimum conditions for production of lixiviant agents. Previous studies have identified methods for maximizing production of gluconic acid and 2,5-diketogluconic acid from G. oxydans , yet the utilization of these and other unidentified G. oxydans metabolites for leaching of rare earth metals is largely unexplored. Continuous cultures exhibited sustained organic acid production for at least 110 hours, while batch fermentations showed slowed growth rates after 16 hours. Several parameters, namely optical density, dissolved oxygen, organic acid concentration and pH, were monitored to characterize the steady state conditions of the fermentation process. The observed trend was increasing acidity with decreasing dilution rates, as the lowest dilution rate of 0.05 hr -1 yielded the highest gluconic acid concentration of 176 mM and lowest pH of 2.20. Trace amounts of 2,5-diketogluconic acid were detected only at the 0.05 hr-1 dilution rate, likely because the pH of the bioreactors was not maintained within the window for gluconate dehydrogenase activity [Silberbach, M., et al., Appl Microbiol Biotechnol, 2003. 62(1): p. 92-8].

60 APPLIED LIFE SCIENCES↗
DOE OSTI2012

Benefits of a Biological Monitoring Program for Assessing Remediation Performance and Long-Term Stewardship - 12272

The Biological Monitoring and Abatement Program (BMAP) is a long-running program that was designed to evaluate biological conditions and trends in waters downstream of Department of Energy (DOE) facilities in Oak Ridge, Tennessee. BMAP monitoring has focused on aquatic pathways from sources to biota, which is consistent with the sites' clean water regulatory focus and the overall cleanup strategy which divided remediation areas into watershed administrative units. Specific programmatic goals include evaluating operational and legacy impacts to nearby streams and the effectiveness of implemented remediation strategies at the sites. The program is characterized by consistent, long-term sampling and analysis methods in a multidisciplinary and quantitative framework. Quantitative sampling has shown conclusively that at most Oak Ridge stream sites, fish and aquatic macro-invertebrate communities have improved considerably since the 1980s. Monitoring of mercury and PCBs in fish has shown that remedial and abatement actions have also improved stream conditions, although in some cases biological monitoring suggests further actions are needed. Follow-up investigations have been implemented by BMAP to identify sources or causes, consistent with an adaptive management approach. Biological monitoring results to date have not only been used to assess regulatory compliance, but have provided additional benefits in helping address other components of the DOE's mission, including facility operations, natural resource, and scientific goals. As a result the program has become a key measure of long-term trends in environmental conditions and of high value to the Oak Ridge environmental management community, regulators, and the public. Some of the BMAP lessons learned may be of value in the design, implementation, and application of other long-term monitoring and stewardship programs, and assist environmental managers in the assessment and prediction of the effectiveness of remedial actions and pollution abatement. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

Dynamic Responses of Trace Metal Bioaccessibility to Fluctuating Redox Conditions in Wetland Soils and Stream Sediments

Natural aquatic systems undergo fluctuating redox conditions due to microbial activity, varying water saturation levels, and nutrients dynamics. With fluctuating redox conditions, trace metals can mobilize or sequester in response to changes in iron and sulfur speciation and the concentrations and lability of organic carbon. This study examined the effect of redox fluctuations on trace metal mobility in samples collected from two different natural aquatic systems: riparian wetlands and a stream. The wetland soils contained low sulfur and total Fe contents as compared to stream sediments. The mineral composition at both sites was dominated by quartz. We incubated water-saturated soils under three cycles of anoxic-oxic conditions (τanoxic:τoxic = 3) spanning 24 days and monitored the change in dissolved and bioavailable metal concentrations. For both natural systems, reduction of iron oxides under anoxic conditions caused Co and Zn release. In contrast, oxidation of sulfides mobilized Cu under oxic conditions in both sites. In wetland soils, dissolution of Fe (hydr)oxides increased Ni solubility; however, in stream sediments, Ni release occurred when sulfides or organic matter were oxidized. For stream sediments, each subsequent redox cycle increased the bioavailability of trace metals. Redox fluctuations in wetland soils increased bioavailable Zn and Cu and decreased bioavailable Ni and Co. This study illustrates that different trace metals display distinct bioavailability patterns during redox fluctuations in natural environments. The biogeochemical cycling of nutrients in systems with redox fluctuations may be influenced by these trace metal availability patterns in addition to the availability of electron donors and acceptors.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗