Search NASA⌕ Search

SEARCH · Search NASA

Results for “Resource availability”

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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

Climate Impact and GIS Education Using Realistic Applications of Data.gov Thematic Datasets in a Structured Lesson-Based Workbook

This project created a workbook which teaches Earth Science to undergraduate and graduate students through guided in-class activities and take-home assignments organized around climate topics which use GIS to teach key geospatial analysis techniques and cartography skills. The workbook is structured to the White House's Data.gov climate change themes, which include Coastal Flooding, Ecosystem Vulnerability, Energy Infrastructure, Arctic, Food Resilience, Human Health, Transportation, Tribal Nations, and Water. Each theme provides access to framing questions, associated data, interactive tools, and further reading (e.g. The US Climate Resilience Toolkit and National Climate Assessment). Lessons make use of the respective theme's available resources. The structured thematic approach is designed to encourage independent exploration. The goal is to teach climate concepts and concerns, GIS techniques and approaches, and effective cartographic representation and communication results; and foster a greater awareness of publicly available resources and datasets. To reach more audiences more effectively, a two level approach was used. Level 1 serves as an introductory study and relies on only freely available interactive tools to reach audiences with fewer resources and less familiarity. Level 2 presents a more advanced case study, and focuses on supporting common commercially available tool use and real-world analysis techniques.

Satellite Imagery↗
DOE OSTI2020

Temporal Resource Continuity Increases Predator Abundance in a Metapopulation Model: Insights for Conservation and Biocontrol

The amount of habitat in a landscape is an important metric for evaluating the effects of land cover on biodiversity, yet it fails to capture complex temporal dimensions of resource availability that could be consequential for species population dynamics. Here, we use a spatially-explicit predator–prey metapopulation model to test the effect of different spatiotemporal resource patterns on insect predators and their prey. We examined population responses in model landscapes that varied in both the amount and temporal variability of basal vegetation. Further, we examined cases where prey comprised either a single generalist species or two specialist species that use different resources available either early or late in the growing season. We found that predators and generalist prey benefitted from lower temporal variance of basal resources, which increased landscape-scale abundances. However, increasing the amount of basal resources also increased the variability of generalist prey populations. Specialist prey, on the other hand, did not benefit from less temporally variable basal resources, as they were restricted by habitat type, while also suffering greater predation. Predators achieved greater prey suppression in landscapes with less temporally variable resources, but the overall effects on prey abundance depended on prey habitat specialization. Our simulations demonstrate the joint importance of both the amount and temporal variability of resources for understanding how landscape heterogeneity influences biodiversity and ecosystem services such as the biological control of agricultural pests.

Spiesman, Brian↗
DOE OSTI2022

Expert Elicitation for Wave Energy LCOE Futures

As the world faces increasing threats from climate change, the importance of developing renewable energy technologies and reducing their costs have similarly increased. Marine energy technologies (which include wave, tidal, ocean current, ocean thermal and salinity gradient resources) are often referred to as the most nascent and newest suite of renewable technologies under development. There are vast marine energy resources available around the world and within U.S. territorial waters, and as the technologies have continued to develop, the long-term trajectory of cost reductions and performance improvements is of particular interest. This study specifically investigates the long-term cost reduction potential for commercial wave energy technologies, as wave energy represents the largest marine energy resource available to the continental U.S. Similar studies focused on other resources and technologies may follow in the future.

16 TIDAL AND WAVE POWER↗
NASA NTRS2005

International Research on ISS - The Benefits of Working Together

International Space Station is the most complex multinational cooperative space endeavor in history. Interagency agreements define utilization accommodations and resources available to each partner. Based on these arrangements, the partners select and implement research to meet agency goals and objectives. But to optimize the limited resources available to utilization, cooperation among the partners is essential. This paper describes various avenues available for partner cooperation and provides specific examples to demonstrate the value of such cooperation to accelerate and enhance science return.

Uri, John J.↗
DOE OSTI2015

The United States Culture Collection Network (USCCN): Enhancing Microbial Genomics Research through Living Microbe Culture Collections

The mission of the United States Culture Collection Network (USCCN; http://usccn.org) is "to facilitate the safe and responsible utilization of microbial resources for research, education, industry, medicine, and agriculture for the betterment of human kind." Microbial culture collections are a key component of life science research, biotechnology, and emerging global biobased economies. Representatives and users of several microbial culture collections from the United States and Europe gathered at the University of California, Davis, to discuss how collections of microorganisms can better serve users and stakeholders and to showcase existing resources available in public culture collections.

Boundy-Mills, K.↗
NASA NTRS1988

Integrated resource scheduling in a distributed scheduling environment

The Space Station era presents a highly-complex multi-mission planning and scheduling environment exercised over a highly distributed system. In order to automate the scheduling process, customers require a mechanism for communicating their scheduling requirements to NASA. A request language that a remotely-located customer can use to specify his scheduling requirements to a NASA scheduler, thus automating the customer-scheduler interface, is described. This notation, Flexible Envelope-Request Notation (FERN), allows the user to completely specify his scheduling requirements such as resource usage, temporal constraints, and scheduling preferences and options. The FERN also contains mechanisms for representing schedule and resource availability information, which are used in the inter-scheduler inconsistency resolution process. Additionally, a scheduler is described that can accept these requests, process them, generate schedules, and return schedule and resource availability information to the requester. The Request-Oriented Scheduling Engine (ROSE) was designed to function either as an independent scheduler or as a scheduling element in a network of schedulers. When used in a network of schedulers, each ROSE communicates schedule and resource usage information to other schedulers via the FERN notation, enabling inconsistencies to be resolved between schedulers. Individual ROSE schedules are created by viewing the problem as a constraint satisfaction problem with a heuristically guided search strategy.

Zoch, David↗
DOE OSTI2023

Assessing individual movement, habitat use, and behavior of non-breeding marine birds in relation to prey availability in the US Atlantic

Resource availability is a key factor driving marine bird movements and distributions, but direct information on prey availability is difficult to obtain at relevant scales. We present novel methods for describing multi-scale trophic associations, combining movement analyses of marine birds with estimates of forage fish surface aggregations from digital aerial survey data and species occupancy from bottom trawl survey data. We analyzed satellite telemetry data from northern gannets Morus bassanus , red-throated loons Gavia stellata , and long-tailed ducks Clangula hyemalis in the US Atlantic during the non-breeding period. Using discrete-time hidden Markov models to distinguish area-restricted (i.e. putative foraging) from transit movements, we examined how environmental factors influence movement, and how forage fish species distributions and surface aggregations influence habitat use by gannets and loons that have greater dietary reliance. Our results suggest that chlorophyll a concentration significantly affected movement behavior across species, highlighting the importance of higher-productivity areas around estuaries during colder months when regional productivity is low. Though variable across species and seasons, spatial cross-correlation analysis revealed that herring species (Family Clupeidae), including Atlantic menhaden Brevoortia tyrannus , may be important resources; it also showed positive spatial correlations with forage fish aggregations. This suggests that prey patch dynamics and factors driving aggregation formation may be as important as species composition. However, spatial patterns were generally low (<0.3), suggesting a mismatch in spatiotemporal resolution, exemplifying the challenges in quantifying trophic relationships in marine systems. Disentangling predator-prey relationships is critical to understanding the mechanisms driving marine bird behavior in rapidly changing marine systems.

Environmental Sciences & Ecology↗
DOE OSTI2023

Organic carbon enables the biotic engineering of beneficial soil structure in Profundihumic and Haplic Ferralsols

We investigated how organic matter may, directly and indirectly, modify the porosity of Ferralsols, that is, deeply weathered soils of the tropics and subtropics. Although empirical and anecdotal evidence suggests that organic matter accumulation may increase porosity, a mechanistic understanding of the processes underlying this beneficial effect is lacking, especially so for Ferralsols. To achieve our end, we leveraged the fact that the Profundihumic qualifier of Ferralsols (PF) is distinguished from Haplic Ferralsols (HF) by both a much larger average carbon content in the first 1 m of soil depth (19 kg C m -3 in PF vs. 10 kg C m -3 in HF) and a significantly lower bulk density (1.05 ± 0.08 kg L -1 in PF vs. 1.21 ± 0.05 kg L -1 in HF). Through exhaustive modelling of carbon – bulk density relationships, we demonstrate that the lower bulk density of PF cannot be satisfactorily explained by a simple dilution effect. Rather, we found that bulk density correlated with carbon content when combined with carbon: nitrogen ratio (r 2 = 0.51), black carbon content (r 2 = 0.75), and Δ 14 C (r 2 =0.81). Total pore space was greater in PF (61± 3%) than in HF (55 ± 2%), but x-ray computed tomography revealed that pore space inside soil aggregates of 4–5 mm diameter does not vary between the studied Ferralsols. We further observed nearly twice as many roots and burrows in PF compared with HF. We thus infer that the mechanism responsible for the increase in porosity is most likely an enhancement of resource availability (e.g., energy, carbon, and nutrients) for the organisms (earthworms, ants, termites, etc.) that physically displace soil particles and promote soil aggregation. As a result of increased resource availability, soil organisms can create especially the mesoscale structural soil features necessary for unrestricted water flow and rapid gas exchange. In conclusion, this insight paves the way for the development of land management technologies to optimize the physical shape and capacity of the soil bioreactor.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Issues Management Process Course # 38401

The purpose of this training it to advise Issues Management Coordinators (IMCs) on the revised Contractor Assurance System (CAS) Issues Management (IM) process. Terminal Objectives: Understand the Laboratory’s IM process; Understand your role in the Laboratory’s IM process. Learning Objectives: Describe the IM process within the context of the CAS; Describe the importance of implementing an institutional IM process at LANL; Describe the process flow for the Laboratory’s IM process; Apply the definition of an issue; Use available resources to determine initial screening risk levels for issues; Describe the required major process steps for each risk level; Describe the personnel responsibilities for IM process implementation; Access available resources to support IM process implementation.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2019

HVACR Workforce Resources

This fact sheet summarizes available resources to support organizations facing challenges with obtaining a skilled workforce to service their HVAC and refrigeration equipment.

HVAC, Workforce, Energy Efficiency, Heating, Venti↗
DOE OSTI2016

Plant-mycorrhizal interactions mediate plant community coexistence by altering resource demand

As the diversity of plants increases in an ecosystem, so does resource competition for soil nutrients, a process that mycorrhizal fungi can mediate. The influence of mycorrhizal fungi on plant biodiversity likely depends on the strength of the symbiosis between the plant and fungi, the differential plant growth responses to mycorrhizal inoculation, and the transfer rate of nutrients from the fungus to plant. However, our current understanding of how nutrient- plant-mycorrhizal interactions influence plant coexistence is conceptual and thus lacks a uni- fied quantitative framework. To quantify the conditions of plant coexistence mediated by mycorrhizal fungi, we developed a mechanistic resource competition model that explicitly included plant-mycorrhizal symbioses. We found that plant-mycorrhizal interactions shape plant coexistence patterns by creating a tradeoff in resource competition. Especially, a tradeoff in resource competition was caused by differential payback in the carbon resources that plants invested in the fungal symbiosis and/or by the stoichiometric constraints on plants that required additional, less-beneficial, resources to sustain growth. Our results suggested that resource availability and the variation in plant-mycorrhizal interactions act in concert to drive plant coexistence patterns. With this being said and applying our framework, future empirical studies should investigate plant-mycorrhizal interactions under multiple levels of resource availability.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

A Generalized Framework for Service Restoration in a Resilient Power Distribution System

An electric power grid is one of the complex infrastructures, and because of its complex nature, there is simply no way that outages can be completely avoided. Thus, a modern society that depends on reliable electric supply requires a resilient electric system that can recover from disruptions while integrating emerging smart grid technologies. Here, this article presents a novel approach for service restoration in a modern power distribution system with controllable switches and distributed generation (DG) resources for any kind of outage. The proposed framework supports both the traditional service restoration using feeder reconfiguration and the grid-forming DG-assisted intentional islands that are dynamically sized using algorithms based on the fault scenario, available resources, and priority of loads. The problem is formulated as a mixed-integer linear program that incorporates critical system connectivity and operating constraints. Simulations are performed to demonstrate the effectiveness of the proposed approach using a large-scale four-feeder 1069-bus three-phase unbalanced distribution test system. It is demonstrated that the framework is effective in utilizing all available resources in quickly restoring the power supply to improve resiliency during extreme events and is scalable for a large-scale unbalanced power distribution system.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

Habitat-specific seasonal densities of sympatric raccoons and opossums in the southeastern United States

Raccoon and opossum densities have implications for rabies management, but estimates of seasonal densities of both species are lacking for rural nonagricultural habitats of the southeastern United States, a core portion of their geographic range. Consequently, it remains unclear whether the densities of 1 species limit the other, which is possible considering their substantial niche overlap. We carried out a mark–recapture study of raccoons and opossums in 4 rural nonagricultural habitats (bottomland hardwood forest, riparian forest, upland pine forest, and isolated wetlands) in South Carolina, United States (2020 to 2022), and combined this with previous data from the same habitats (2017 to 2019) to estimate habitat-specific spring and fall densities. Raccoon densities ranged from 5.17 ± 0.96 animals/km 2 (bottomland hardwood fall) to 1.63 ± 0.83 animals/km 2 (upland pine spring) and were on average 19% higher in fall compared to spring. Opossum densities ranged from 10.35 ± 1.98 animals/km 2 (bottomland hardwood fall) to 1.11 ± 1.55 animals/km 2 (upland pine spring) with divergent seasonal patterns among habitats. These low densities across all habitats compared to other studies are likely the result of low resource availability, consistent with other habitats that have minimal anthropogenic influence. We observed a positive association between raccoon and opossum densities across trapping grids, suggesting that raccoons do not suppress opossum densities, but that densities of both species increase with increasing resource availability. Furthermore, our results can be used to inform oral rabies vaccination efforts such as refining bait densities and timing of bait distribution in these habitats.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

CERF – A Geospatial Model for Assessing Future Energy Production Technology Expansion Feasibility

Electricity system expansion planning faces significant challenges not only because of commonly modeled uncertainties such as future demand growth, fuel prices, and technology cost and performance, but also because of challenges such as climate change and carbon policies that can affect supply and demand. Changes in energy technology, natural resource availability, and population migration and growth will affect the feasibility of power plant siting, potentially hindering the achievement of policy goals. New modeling approaches are needed that couple future projections of energy system expansion with “on the ground” feasibility modeling—where both are informed by a consistent set of assumptions about future climate trends, resource availability, climate policy, socioeconomics, and environmental regulations. This research describes the development and evaluation of the Capacity Expansion Regional Feasibility (CERF) model, a geospatial tool for scenario analysis of electricity system expansions.

grid expansion, water-energy nexus, power plant si↗
DOE OSTI2016

Balancing global water availability and use at basin scale in an integrated assessment model

Water is essential for the world’s food supply, for energy production, including bioenergy and hydroelectric power, and for power system cooling. Water is already scarce in many regions of the world and could present a critical constraint as society attempts simultaneously to mitigate climate forcing and adapt to climate change, and to provide for a larger and more prosperous human population. Numerous studies have pointed to growing pressures on the world’s scarce fresh water resources from population and economic growth, and climate change. This study goes further. We use the Global Change Assessment Model to analyze interactions between population, economic growth, energy, land and water resources simultaneously in a dynamically evolving system where competing claims on water resources from all claimants—energy, land, and economy—are reconciled with water resource availability—from renewable water, non-renewable groundwater sources and desalinated water—across 14 geopolitical regions, 151 agriculture-ecological zones, and 235 major river basins. We find that previous estimates of global water withdrawal projections are overestimated. Model simulations show that it is more economical in some basins to alter agricultural and energy activities rather than utilize non-renewable groundwater or desalinated water. This study highlights the importance of accounting for water as a binding factor in agriculture, energy and land use decisions in IAMs and implications for global responses to water scarcity, particularly in the trade of agricultural commodities and land-use decisions.

basin↗
DOE OSTI2017

User-Preference-Driven Model Predictive Control of Residential Building Loads and Battery Storage for Demand Response: Preprint

This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility and reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS1993

Generating and evaluating alternate schedules

The demand for and availability of Space Network resources are subject to short-term fluctuations and long-term changes. Generation of acceptable schedules under changing demand and resource availability will require the use of different scheduling policies. This paper identifies several such scheduling policies. It defines metrics for evaluating schedules using the criteria directly related to these scheduling policies. Then it applies the metrics to compare several schedules generated for a scenario representative of 1998 SN demand and resources. Finally, the paper describes a method for using these metrics to evaluate schedules based on multiple criteria.

Reddy, Surender D.↗
DOE OSTI2015

WE-G-BRA-01: Patient Safety and Treatment Quality Improvement Through Incident Learning: Experience of a Non-Academic Proton Therapy Center

Purpose: Incident learning has been proven to improve patient safety and treatment quality in conventional radiation therapy. However, its application in proton therapy has not been reported yet to our knowledge. In this study, we report our experience in developing and implementation of an in-house incident learning system. Methods: An incident learning system was developed based on published principles and tailored for our clinical practice and available resource about 18 months ago. The system includes four layers of error detection and report: 1) dosimetry peer review; 2) physicist plan quality assurance (QA); 3) treatment delivery issue on call and record; and 4) other incident report. The first two layers of QA and report were mandatory for each treatment plan through easy-to-use spreadsheets that are only accessible by the dosimetry and physicist departments. The treatment delivery issues were recorded case by case by the on call physicist. All other incidents were reported through an online incident report system, which can be anonymous. The incident report includes near misses on planning and delivery, process deviation, machine issues, work flow and documentation. Periodic incident reviews were performed. Results: In total, about 116 errors were reported through dosimetry review, 137 errors through plan QA, 83 treatment issues through physics on call record, and 30 through the online incident report. Only 8 incidents (2.2%) were considered to have a clinical impact to patients, and the rest of errors were either detected before reaching patients or had negligible dosimetric impact (<5% dose variance). Personnel training & process improvements were implemented upon periodic incident review. Conclusion: An incident learning system can be helpful in personnel training, error reduction, and patient safety and treatment quality improvement. The system needs to be catered for each clinic’s practice and available resources. Incident and knowledge sharing among proton centers are encouraged.

60 APPLIED LIFE SCIENCES↗