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Results for “condition monitoring”

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 1,513 records · Page 84

All sources NASA NTRS DOE OSTI

NASA NTRS1978

System-state and operating condition sensitive control method and apparatus for electric power delivery systems

This invention provides a method and apparatus for determining a precise switching sequence for the power switching elements of electric power delivery systems of the on-off switching type and which enables extremely fast transient response, precise regulation and highly stable operation. The control utilizes the values of the power delivery system power handling network components, a desired output characteristic, a system timing parameter, and the externally imposed operating conditions to determine where steady state operations should be in order to yield desired output characteristics for the given system specifications. The actual state of the power delivery system is continuously monitored and compared to a state-space boundary which is derived from the desired equilibrium condition, and from the information obtained from this comparison, the system is moved to the desired equilibrium condition in one cycle of switching control. Since the controller continuously monitors the power delivery system's externally imposed operating conditions, a change in the conditions is immediately sensed and a new equilibrium condition is determined and achieved, again in a single cycle of switching control.

Burns, III, William Wesley↗

NASA NTRS2016

In-Situ Measurement of the Height of Condensed Water in Steam Pipes with Dynamic Flow

A method based on the use of enhanced filtered Hilbert envelope of the wave signal was developed in order to monitor the height of condensed water through the wall of steam pipes having dynamic flow conditions. A prototype testbed was designed and fabricated in this study to simulate the dynamic flow conditions including the air stream flowing above the water and bubble induced disturbance. A dual-transducer was used to perform the test as a basis for the multiple transducers system to facilitate the detectability and reliability for long term monitoring of the condensed water height in dynamic conditions. The results demonstrated that the method of measuring the water height using multiple-transducer system employing the developed novel signal processing technique is an efficient and accurate tool for practical applications.

water level in pipe↗

DOE OSTI2019

Embedded Optical Sensing Systems For Distribution Transformer Monitoring

Traditional utility monitoring systems do not provide real-time visibility into the condition of transformers or accurate performance measurements. This has resulted in the use of lagging indicators, such as oil sample analysis, typically requiring expensive field visits, grid outages, and laboratory sample testing. This presentation reviews the use of optical sensing systems for managing transformers and improving grid resiliency and safety. The sensing systems allow direct internal monitoring of critical transformer components. Versatility covering different monitoring parameters of interest in embedded configurations for new transformers and a retrofittable configuration for older transformers is achieved by applying hair-thin multiplexed fiber-optic and other low-profile optical sensors in combination with a high-resolution optical readout and advanced analytics. Under an initiative funded by the DOE Office of Electricity, PARC, GE and Con Edison built, tested, and qualified commercial network transformers with embedded optical sensing systems. The parameters monitored were validated across a range of scenarios with lab instruments typically used for qualification testing. An ongoing field trial to demonstrate the robustness of the technology for remote monitoring through the industrial internet under demanding grid deployment conditions in New York City is showing promise toward scale-up of the technology. This presentation will provide an overview of the typical pain points in managing transformers and parameters for monitoring. It will also cover the requirements for highly constrained installations that need to have a larger capacity and flexible rating but that must fit into a tight space. The unique capabilities of optical sensing systems and a low-cost approach to interpreting the signals from sensors in transformers for predictive maintenance will be covered. The presentation will discuss the compatibility of the sensors in the transformer environment. It will discuss the validation testing per IEEE standards that enabled the solution to be implemented in field-deployable commercial transformers. The initial results from the field deployment and the potential for the technology to provide systematic alerts for unsafe/unexpected events will be discussed. The technology could enable utility professionals to gain information they can use to better plan for maintenance/management, and improve grid performance. This would in turn accommodate DERs and other evolving grid market dynamics.

24 POWER TRANSMISSION AND DISTRIBUTION↗

NASA NTRS2011

Probabilistic Structural Health Monitoring of the Orbiter Wing Leading Edge

A structural health monitoring (SHM) system can contribute to the risk management of a structure operating under hazardous conditions. An example is the Wing Leading Edge Impact Detection System (WLEIDS) that monitors the debris hazards to the Space Shuttle Orbiter s Reinforced Carbon-Carbon (RCC) panels. Since Return-to-Flight (RTF) after the Columbia accident, WLEIDS was developed and subsequently deployed on board the Orbiter to detect ascent and on-orbit debris impacts, so as to support the assessment of wing leading edge structural integrity prior to Orbiter re-entry. As SHM is inherently an inverse problem, the analyses involved, including those performed for WLEIDS, tend to be associated with significant uncertainty. The use of probabilistic approaches to handle the uncertainty has resulted in the successful implementation of many development and application milestones.

Yap, Keng C.↗

DOE OSTI2013

2012 Annual Wastewater Reuse Report for the Idaho National Laboratory Site's Central facilities Area Sewage Treatment Plant

This report describes conditions, as required by the state of Idaho Wastewater Reuse Permit (#LA-000141-03), for the wastewater land application site at Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant from November 1, 2011, through October 31, 2012. The report contains the following information: • Site description • Facility and system description • Permit required monitoring data and loading rates • Status of compliance conditions and activities • Discussion of the facility’s environmental impacts. During the 2012 permit year, no wastewater was land-applied to the irrigation area of the Central Facilities Area Sewage Treatment Plant.

2012↗

DOE OSTI2020

Battery Monitoring System

The component that is powered by the battery pack being monitored is a valuable asset and must be in working condition at all times. Battery chemistry and characteristics have a major role in how to evaluate the state of the battery. The battery monitoring system has many parts that lead to an accurate battery reading. The components consist of a coulomb counting device, end of life voltage detection, a consideration of use for a real-time clock (RTC), temperature sensor, and non-volatile random-access memory (NVRAM). The combination of these elements allows the monitoring system to be highly reliant. Moving forward a better implementation of the ideas in this paper and further testing should ensure a high-quality battery monitoring system.

25 ENERGY STORAGE↗

NASA NTRS1975

Applications of chemiluminescence to bacterial analysis

Luminol chemiluminescence method for detecting bacteria was based on microbial activation of the oxidation of the luminol monoanion by hydrogen peroxide. Elimination of the prior lysing step, previously used in the chemiluminescence technique, was shown to improve considerably the reproducibility and accuracy of the method in addition to simplifying it. An inexpensive, portable photomultiplier detector was used to measure the maximum light intensity produced when the sample is added to the reagent. Studies of cooling tower water show that the luminol chemiluminescence technique can be used to monitor changes in viable cell population both under normal conditions and during chlorine treatment. Good correlation between chemiluminescence and plate counts was also obtained in the analysis of process water used in paper mills. This method showed good potential for monitoring the viable bacteria populations in activated sludge used in waste treatment plants to digest organic matter.

Searle, N. D.↗

NASA NTRS1974

Life support subsystem monitoring instrumentation

The recognition of the need for instrumentation in manned spacecraft life-support subsystems has increased significantly over the past several years. Of the required control and monitoring instrumentation, this paper will focus on the monitoring instrumentation as applied to life-support subsystems. The initial approach used independent sensors, independent sensor signal conditioning circuitry, and independent logic circuitry to provide shutdown protection only. This monitoring system was replaced with a coordinated series of printed circuit cards, each of which contains all the electronics to service one sensor and provide performance trend information, fault detection and isolation information, and shutdown protection. Finally, a review of sensor and instrumentation problems is presented, and the requirement for sensors with built-in signal conditioning and provisions for in situ calibration is discussed.

Powell, J. D.↗

DOE OSTI2012

Scientific Opportunities for Monitoring of Environmental Remediation Sites (SOMERS)

The US Department of Energy (DOE) is responsible for risk reduction and cleanup of its nuclear weapons complex. DOE maintains the largest cleanup program in the world, currently spanning over a million acres in 13 states. The inventory of contaminated materials includes 90 million gallons of radioactive waste, 6.4 trillion liters of groundwater, and 40 million cubic meters of soil and debris. It is not feasible to completely restore many sites to predisposal conditions. Any contamination left in place will require monitoring, engineering controls and/or land use restrictions to protect human health and environment. Research and development efforts to date have focused on improving characterization and remediation. Yet, monitoring will result in the largest life-cycle costs and will be critical to improving performance and protection. Through an inter-disciplinary effort, DOE is addressing a need to advance monitoring approaches from sole reliance on cost- and labor-intensive point-source monitoring to integrated systems-based approaches such as flux-based approaches and the use of early indicator parameters. Key objectives include identifying current scientific, technical and implementation opportunities and challenges, prioritizing science and technology strategies to meet current needs within the DOE complex for the most challenging environments, and developing an integrated and risk-informed monitoring framework.

Bunn, Amoret L↗

DOE OSTI2012

Scientific Opportunities for Monitoring of Environmental Remediation Sites - (SOMERS)

environmental restoration↗

DOE OSTI2012

Scientific Opportunities for Monitoring of Environmental Remediation Sites (SOMERS)

Bunn, Amoret L.↗

DOE OSTI2017

Observational needs for estimating Alaskan soil carbon stocks under current and future climate

Abstract Representing land surface spatial heterogeneity when designing observation networks is a critical scientific challenge. Here we present a geospatial approach that utilizes the multivariate spatial heterogeneity of soil‐forming factors—namely, climate, topography, land cover types, and surficial geology—to identify observation sites to improve soil organic carbon (SOC) stock estimates across the State of Alaska, USA. Standard deviations in existing SOC samples indicated that 657, 870, and 906 randomly distributed pedons would be required to quantify the average SOC stocks for 0–1 m, 0–2 m, and whole‐profile depths, respectively, at a confidence interval of 5 kg C m −2 . Using the spatial correlation range of existing SOC samples, we identified that 309, 446, and 484 new observation sites are needed to estimate current SOC stocks to 1 m, 2 m, and whole‐profile depths, respectively. We also investigated whether the identified sites might change under future climate by using eight decadal (2020–2099) projections of precipitation, temperature, and length of growing season for three representative concentration pathway (RCP 4.5, 6.0, and 8.5) scenarios of the Intergovernmental Panel on Climate Change. These analyses determined that 12 to 41 additional sites (906 + 12 to 41; depending upon the emission scenarios) would be needed to capture the impact of future climate on Alaskan whole‐profile SOC stocks by 2100. The identified observation sites represent spatially distributed locations across Alaska that captures the multivariate heterogeneity of soil‐forming factors under current and future climatic conditions. This information is needed for designing monitoring networks and benchmarking of Earth system model results.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2024

The Role of Side Chains and Hydration on Mixed Charge Transport in n ‐Type Polymer Films

Abstract Introducing ethylene glycol (EG) side chains to a conjugated polymer backbone is a well‐established synthetic strategy for designing organic mixed ion‐electron conductors (OMIECs). However, the impact that film swelling has on mixed conduction properties has yet to be scoped, particularly for electron‐transporting (n‐type) OMIECs. Here, the authors investigate the effect of the length of branched EG chains on mixed charge transport ofn‐type OMIECs based on a naphthalene‐1,4,5,8‐tetracarboxylic‐diimide‐bithiophene backbone. Atomic force microscopy (AFM), grazing‐incidence wide‐angle X‐ray scattering (GIWAXS), and scanning tunneling microscopy (STM) are used to establish the similarities between the common‐backbone films in dry conditions. Electrochemical quartz crystal microbalance with dissipation monitoring (EQCM‐D) and in situ GIWAXS measurements reveal stark changes in film swelling properties and microstructure during electrochemical doping, depending on the side chain length. It is found that even in the loss of the crystallite content upon contact with the aqueous electrolyte, the films can effectively transport charges and that it is rather the high water content that harms the electronic interconnectivity within the OMIEC films. These results highlight the importance of controlling water uptake in the films to impede charge transport inn‐type electrochemical devices.

Chemistry↗

DOE OSTI2021

Pigment modulation in response to irradiance intensity in the fast-growing alga Picochlorum celeri

Picochlorum celeri has among the fastest photoautotrophic growth rates (~2 h doubling time in optimal conditions) reported to date for a marine alga. This study comprehensively analyzes the levels of Picochlorum celeri photosynthetic pigments, which can reach up to ~13% of the total particulate organic carbon (POC) under light-limiting conditions. The main Picochlorum celeri pigments identified include: chlorophyll a, chlorophyll b, lutein, β-carotene, canthaxanthin, violaxanthin, neoxanthin, zeaxanthin and antheraxanthin. The ketocarotenoid canthaxanthin can accumulate up to 120 mg L -1 in Picochlorum celeri liquid culture; ~12% of it was found in an extracellular polysaccharide matrix. Using a solar-simulating automated photobioreactor, we monitor the photoacclimation of cultures maintained in unshaded conditions (<0.5 μg mL -1 of total chlorophyll) through transitions from high irradiance (1000 μmoles photosynthetically active radiation (PAR) m -2 s -1 ) to low irradiance (60 μmoles PAR m -2 s -1 ), and conversely from low to high irradiance. Canthaxanthin and zeaxanthin accumulation are among the most rapid modulation responses when cultures are shifted from low to high irradiance. The violaxanthin, antherazanthin, and zeaxanthin (VAZ) pool is ~3-fold higher in high-light cultures, suggesting that the VAZ cycle combined with a dramatic reduction in chlorophyll levels are among the major mechanisms used in Picochlorum celeri to efficiently acclimate to high-irradiance levels. Responsive pigment modulation was also observed in denser cultures (~0.65 g L –1 ) grown under a diel cycle (pond-mimicking conditions). Furthermore, this research provides unique insights into the dynamics of pigment modulation and photoacclimation in response to changing irradiance in a biotechnologically promising alga and will inform future pigment engineering strategies to further improve light capture and biomass accumulation.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2017

Leucine-induced localization of Leucyl-tRNA synthetase in lysosome membrane

Leucyl-tRNA synthetase (LRS) plays major roles in providing leucine-tRNA and activating mechanistic target of rapamycin complex 1 (mTORC1) through intracellular leucine sensing. mTORC1 activated by amino acids affects the influence on physiology functions including cell proliferation, protein synthesis and autophagy in various organisms. Biochemical results demonstrating leucine sensing have been published, but visual results are lacking. Therefore, we observed the location of LRS with and without leucine using stimulated emission depletion (STED) microscopy one of the super-resolution microscopy and transmission electron microscopy (TEM). This revealed that LRS was translocated to the lysosome on addition of leucine. The translocation was inhibited by treatment with compound BC-LI-0186, disrupting the interaction between RagD and LRS. Immuno-TEM revealed a clear decrease in LRS translocation to the lysosome on addition of the inhibitor. This direct visualization of leucine sensing and LRS translocation to the lysosome was related to mTORC1 activation. To study the relationship between mTORC1 activation and LRS translocation, we monitored the change in autophagy for each condition using TEM and CLSM. The results showed a decrease in autophagy on addition of leucine, demonstrating crosstalk between leucine sensing, LRS translocation, RagD interaction, and mTORC1 activation. - Highlights: • LRS activates mTORC1 via intracellular leucine sensing. • We used STED microscopy and TEM to observe effect of leucine on LRS localization in lysosomes. • LRS translocated to lysosomes and autophagy decreased after adding leucine. • BC-LI-0186 inhibited translocation of LRS. • LRS inhibition or LRS-mediated mTORC1 suppression can be a new therapeutic target.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2017

Anderson acceleration and application to the three-temperature energy equations

The Anderson acceleration method is an algorithm for accelerating the convergence of fixed-point iterations, including the Picard method. Anderson acceleration was first proposed in 1965 and, for some years, has been used successfully to accelerate the convergence of self-consistent field iterations in electronic-structure computations. Recently, the method has attracted growing attention in other application areas and among numerical analysts. Compared with a Newton-like method, an advantage of Anderson acceleration is that there is no need to form the Jacobian matrix. Thus the method is easy to implement. In this paper, an Anderson-accelerated Picard method is employed to solve the three-temperature energy equations, which are a type of strong nonlinear radiation-diffusion equations. Two strategies are used to improve the robustness of the Anderson acceleration method. One strategy is to adjust the iterates when necessary to satisfy the physical constraint. Another strategy is to monitor and, if necessary, reduce the matrix condition number of the least-squares problem in the Anderson-acceleration implementation so that numerical stability can be guaranteed. Numerical results show that the Anderson-accelerated Picard method can solve the three-temperature energy equations efficiently. Compared with the Picard method without acceleration, Anderson acceleration can reduce the number of iterations by at least half. A comparison between a Jacobian-free Newton–Krylov method, the Picard method, and the Anderson-accelerated Picard method is conducted in this paper.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2025

Carbon monoxide chemistry of α-V70I Mo-nitrogenase: Evidence from EPR- and IR-monitored photolysis – or, what a difference a methyl makes

A critical step in the global nitrogen cycle is the conversion of dinitrogen into biologically accessible ammonia. In Nature this is accomplished by the nitrogenase (N 2 ase) family of enzymes. Carbon monoxide (CO) has long been known as an inhibitor of dinitrogen reduction by N 2 ase, but it can also be a substrate of the enzyme, when it is catalytically reduced to hydrocarbons. Understanding the CO interactions with N 2 ases are thus relevant to both dinitrogen fixation and Fischer-Tropsch-like chemistry. Here, in this work, the interaction of CO with the α-V70I variant of Azotobacter vinelandii MoFe N 2 ase was investigated using electron paramagnetic resonance (EPR) and infrared (IR) monitored photolysis of bound CO under cryogenic conditions. This was supplemented by further analysis of stopped-flow Fourier transform IR (SF-FT-IR) data under turnover conditions. The α-V70I variant adds a single methyl group close to the FeMo-cofactor active site, and the results show that this inhibits and slows, but does not substantially chemically change, the binding of CO to the FeMocofactor. The EPR spectra of both the hi-CO and lo-CO states closely resemble those from the wild-type enzyme. Similarly, the SF-FT-IR spectra of CO inhibited α-V70I and wild-type enzyme are strikingly similar, showing only small shifts in band energies which allow better interpretation of the published wild-type spectra. The extra carbon does, however, impact and inhibit the photochemical release and migration of CO at cryogenic temperatures, resulting in novel CO-bound species. These include a product species, termed Lo-1*, which may involve CO photochemically migrating on the FeMo-cofactor.

Carbon monoxide↗

DOE OSTI2025

From pixels to patterns: Coupling Optical Coherence Tomography and machine learning for monitoring coastal wetland root systems

Coastal wetlands are crucial in shoreline stabilization, carbon sequestration, and storm protection. Yet, due to limitations in traditional destructive sampling techniques, the belowground biomass (live root mass) and necromass (dead and decaying roots) remain difficult to assess in coastal wetlands, limiting our understanding on coastal resilience, nutrient cycling, and soil structure. This study employs Optical Coherence Tomography (OCT) as a high-resolution imaging technique to analyze root biomass and necromass in the Terrebonne Basin, Louisiana. A Random Forest (RF) model was developed to classify root health states based on OCT-derived features, achieving an accuracy of 70% in distinguishing live from dead root segments. The results demonstrate that OCT, combined with ML, offers a promising novel approach to root analysis, providing fine-scale insights into root morphology and decay patterns that are not easily captured by conventional methods. This research lays the foundation for future integration of OCT with complementary imaging modalities such as X-ray Computed Tomography (XCT) and advanced ML algorithms to enhance classification accuracy and scalability. Future work aims to expand the dataset diversity across different wetland types and apply the methodology for large-scale, repeatable assessments of root biomass turnover and accumulation, with important implications for wetland monitoring, conservation, and restoration under changing environmental conditions.

AI/ML↗