Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “linkage”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

Using the NASA Giovanni DICCE Portal to Investigate Land-Ocean Linkages with Satellite and Model Data

Data-enhanced Investigations for Climate Change Education (DICCE), a NASA climate change education project, employs the NASA Giovanni data system to enable teachers to create climate-related classroom projects using selected satellite and assimilated model data. The easy-to-use DICCE Giovanni portal (DICCE-G) provides data parameters relevant to oceanic, terrestrial, and atmospheric processes. Participants will explore land-ocean linkages using the available data in the DICCE-G portal, in particular focusing on temperature, ocean biology, and precipitation variability related to El Ni?o and La Ni?a events. The demonstration includes the enhanced information for educators developed for the DICCE-G portal. The prototype DICCE Learning Environment (DICCE-LE) for classroom project development will also be demonstrated.

Acker, James G.↗
NASA NTRSDate not supplied

Asteroid (142) Polana at 3 µM and Its Linkage to the Primitive Asteroid (101955) Bennu

The Polana family is a low-albedo family located at a low inclination and a semimajor axis of ~2.42 au in the inner main asteroid belt. This family is likely the source of primitive near-Earth asteroids, including the OSIRIS-REx mission target (101955) Bennu. The B-type asteroid 142 Polana is the largest remnant of the "New Polana" family, and it has been spectrally (~0.5-2.5 µm) and dynamically linked to Bennu. Here, we investigate the compositional linkage of asteroids Polana and Bennu using spectra measured at longer wavelengths (~1.6-4.0 µm), which cover the 3- µm band. Polana’s spectra were measured at NASA IRTF using the LXD mode of SpeX. Bennu’s spectra were measured by OSIRIS-REx’s OVIRS spectrometer and revealed that this primitive asteroid is hydrated consistent with CM, CI, or CR carbonaceous chondrites. Polana’s LXD spectra, on the hand, show that the parent body of the Polana family is not hydrated (i.e., no absorption band at ~ 3.0 µm). Additionally, Polana’s LXD spectra do not indicate the presence of organics and/or carbonates. Polana's lack of significant water, organic, and carbonate spectral features on its surface could be related to the degree of heating in the Polana family-forming event and the reaccretion of ejecta that contributed to additional heating. The Polana family-forming event could also expose the parent body's dehydrated, organic/carbonate-poor interior. These results will be placed in the context of other low-albedo families and background objects in the inner main belt. An approved JWST program to observe Polana (with both NIRSpec and MIRI) will be able to assess if there is a Ryugu-like band and should allow a comparison of the MIR spectrum to Bennu.

Driss Takir↗
NASA NTRS2023

Transformable Linkage-Based Gripper for Multi-Mode Grasping and Manipulation

Gripper hardware design often involves a trade-off between distinct and sometimes opposing goals (e.g., high grasping force vs. gentleness). To address this trade-off within a single device, we present a multi-mode gripper with fingers that are scissor linkages, that can actively transform between three distinct modes by varying the number and locations of mechanical singularities. Each of these modes has properties that are suitable for specific needs. Mode 1 provides high grip strength, using a short lever arm and rigid structure. Mode 2 allows precise finger positioning and in-hand manipulation, using two independently controlled DOFs per finger. Mode 3 provides underactuated grasping that can passively adapt to delicate or irregularly shaped objects, with four DOFs per finger. The kinematic relationships, joint torques, and fingertip forces are derived analytically for each of the three modes. Gripper performance and the kinematic model are verified experimentally.

Junghan Kwon↗
DOE OSTI2023

Linkages Between NREL's dGen, REopt, and SAM Models

This webinar describes linkages between NREL's dGen, SAM, and REopt tools that were developed as a part of the RiDER project, including specifying utility rates in the SAM GUI and using them in dGen adoption analysis, and using REopt to determine optimal system sizes for dGen agents.

dGen↗
DOE OSTI2026

Soil microbial ecology and microbiome-metabolite linkages improve understanding of ecosystem states along terrestrial-aquatic interfaces

Coastal soils are dynamic systems where unique microbial niches are shaped by the intensity and duration of flooding between the terrestrial and aquatic boundaries of the terrestrial-aquatic interface (TAI). We aimed to understand the soil microbial community (16S rRNA gene) along the TAIs of a freshwater versus estuarine region and how it relates to organic matter (OM, via Fourier Transform Ion Cyclotron Resonance Mass Spectrometry). We studied the TAI gradients along a transect from upland (forested), transition (stressed forest), to wetland at three sites in each of the Lake Erie (freshwater) and Chesapeake Bay (estuarine) regions. Microbial communities differed significantly by region, transect position, and site. Contrary to expectations, given their dynamic hydrologies, transitions represented midpoints in microbial richness and diversity. We identified a core microbiome conserved across all transect positions within a region, highlighting potential microbial functions most resilient to environmental change. Indicator taxa unique to each transect position defined specific niches shaped by soil biogeochemistry. Co-expression networks of feature-level β-nearest-taxon indices revealed positive relationships in bacterial and OM feature contributions to community assembly. Our study provides critical insights into microbial communities at the forefront of hydrological changes in coastal areas that connect the land to lakes and oceans and remain vulnerable to changing weather patterns.

coastal ecosystems↗
DOE OSTI2020

Covalent Linkage and Macrocylization Preserve and Enhance Synergistic Interactions in Catalytic Amyloids

The self-assembly of short peptides into catalytic amyloid-like nanomaterials has proven to be a powerful tool in both understanding the evolution of early proteins and identifying new catalysts for practically useful chemical reactions. Here we demonstrate that both parallel and antiparallel arrangements of beta-sheets can accommodate metal ions in catalytically productive coordination environments. Moreover, synergistic relationships, identified in catalytic amyloid mixtures, can be captured in macrocyclic and sheet-loop-sheet species, that offer faster rates of assembly and provide more complex asymmetric arrangements of functional groups, thus paving the way for future designs of amyloid-like catalytic proteins. Finally, our findings show how initial catalytic activity in amyloid assemblies can be propagated and improved in more-complex molecules, providing another link in a complex evolutionary chain between short, potentially abiotically produced peptides and modern-day enzymes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Linkages between riverine flooding risk and economic damage over the continental United States

Economic damages from riverine flooding are expected to grow because of climate change. Yet, there are few 7 studies analyzing flooding damages in the U.S. that clearly measure the roles of hazard, exposure, and vulnerability 8 separately and locally. A lack of this knowledge prohibits spatially detailed predictions of future damages. By being 9 able to separate into these three risk factors, we provide all necessary inputs for uncertainty analysis of the flooding-10 damages forecasts that can incorporate new predictive scenarios for each component. To analyze the flooding risk 11 factors of non-coastal counties within the contiguous U.S. between 1999-2018, we gathered information on (1) 12 property and human damages from flooding, (2) maximum annual river discharge, (3) the number of housing units 13 and the years in which they were built, and (4) the incidence of flooding events. We used the method of trimmed 14 least absolute deviated and trimmed least square estimators to obtain the individual impact of hazard, exposure, and 15 vulnerability in the context of censored flooding damages for panel data. The resulting estimates indicate that 16 exposure has been the main driver of flooding risk for most counties in the U.S. Here, we use these estimates to describe 17 the main source of flooding risk for non-coastal counties for the 1999-2018 period.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

The Linkage Between Electro-Chemical Mechanical Instabilities in Battery Materials

Battery chemistry must be diversified to achieve a sustainable energy landscape by effectively utilizing renewable energy sources. Alkali metal-ion, all-solid-state, metal–air batteries, and multivalent batteries offer unique cost, safety, raw material abundance, energy, and power density solutions. However, realizing these “beyond Li-ion batteries” must uncover their working principles and performance & property relationships. In this aspect, mitigating chemo-mechanical instabilities in the structure and surface of the electrodes plays a crucial role in their performance. Unfortunately, the coupling between electrochemical and mechanical interactions is often poorly understood due to a lack of operando characterization. Here, this review article explains the working principles of curvature measurement and digital image correlation for measuring stress and strain generations in battery materials. We provided specific examples of how these operando mechanical measurements shed light on instabilities in alkali metal ion electrodes, solid electrolytes, Li-O 2 batteries, and aqueous Zn-ion batteries. Operando mechanical measurements offer an effective way to map changes in the physical fingerprint of the battery materials, therefore providing crucial information to elucidate instabilities in battery materials.

25 ENERGY STORAGE↗
DOE OSTI2021

RNA-Seq-based high-resolution linkage map reveals the genetic architecture of fruiting body development in shiitake mushroom, Lentinula edodes

Fruiting body development (FBD) of mushroom-forming fungi has attracted tremendous interest. However, the genetic and molecular basis of FBD is poorly known. Here, using Lentinula edodes (shiitake) as a model, we deciphered the genetic architecture underlying fruiting body-related traits (FBRTs) by combined genomic, genetic and phenotypic data. Using RNA-Seq of fruiting bodies from 110 dikaryons in a bi-parental mapping population, we constructed an ultra-high-density genetic map of L. edodes (Lemap2.0) with a total length of 810.14 cM, which covered 81.7% of the shiitake genome. A total of 94 scaffolds of the shiitake genome were aligned to Lemap2.0 and re-anchored into nine pseudochromosomes. Then via quantitative trait locus (QTL) analysis, we disclosed an outline of the genetic architecture of FBD in shiitake. Twenty-nine QTLs and three main genomic regions associated with FBD of shiitake were identified. Using meta-QTL analysis, seven pleiotropic QTLs for multiple traits were detected, which contributed to the correlations of FBRTs. In the mapped QTLs, the expression of 246 genes were found to significantly correlate with the phenotypic traits. Thirty-three of them were involved in FBD and could represent candidate genes controlling the shape and size of fruiting bodies. Collectively, our findings have advanced our understanding of the genetic regulation of FBD in shiitake and mushroom-forming fungi at large.

59 BASIC BIOLOGICAL SCIENCES↗