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Results for “information barrier”

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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Issues in Bi-Directional Interoperability between BIM and BEM

The state-of-the-art interoperability between Building Information Modeling (BIM) and Building Energy Modeling (BEM) is mainly one-way. BEM software like EnergyPlus takes design input from BIM and simulates the energy consumption of the building. BIM, however, is unable to leverage energy simulation results from BEM smoothly. This lack of bi-directional interoperability between BIM and BEM prevents buildings from seeking more energy-efficient design options and limits BIM applications in optimal generative design. In this research, the authors have conducted the following activities related to two-way interoperability between BIM and BEM: (1) surveyed its current status through literature review, (2) investigated barriers to the bi-directional interoperability, and (3) suggested possible approaches to enable bi-directional interoperability and research outlook in the field. As a result, the authors have identified three main barriers to BIM BEM interoperability, namely, inefficient collaboration, limited scope in information transformation, and lack of BEM to BIM transformation. Future directions are suggested to address these barriers.

building design↗
DOE OSTI2024

Simulating Crystallization in a Colloidal System Using State Predictive Information Bottleneck Based Enhanced Sampling

Here, we investigate crystal nucleation in supersaturated colloid suspensions using enhanced molecular dynamics simulations augmented with machine learning techniques. The simulations reveal that crystallization in the model colloidal system studied here, with particles interacting through a repulsive screened Coulomb Yukawa potential, proceeds from vapor to dense liquid droplet to crystalline phases across multiple high barriers. Employing a one-dimensional reaction coordinate derived from the State Predictive Information Bottleneck framework, our simulations capture back-and-forth phase transitions across multiple barriers effectively in biased metadynamics simulations. We obtain relative free energy differences between different phases and also quantify the roles of different molecular level features in driving the phase changes.

Chemistry↗
DOE OSTI2024

Product Innovation to Increase Low-to-Moderate-Income Customers' Adoption of Community Solar PV

This study aims to comprehensively analyze community solar project preferences for consumers and suppliers by conducting three distinct analyses. First we analyze the predictors of community solar contract adoption to understand how individual priorities affect the probability of adoption. Using an original data set of survey responses from potential community solar customers, we analyzed the predictors of contract adoption by employing a weighted logit model. We find that individuals who were previously familiar with community solar projects were significantly more likely to adopt than those who were not familiar. Secondly, a survey of community solar developers and financiers identified industry perceived barriers to community solar access and inclusion. Thirdly, we gathered payment performance information from community solar initiatives to measure how financial risks are perceived and how they interact with customer demographics. Our study is beneficial to the public by providing insights into the drivers and barriers of community solar adoption and sheds light on the importance of understanding individual priorities in designing effective community solar policies. The community solar industry has changed significantly since the beginning of this project. The industry continues to grow at a rapid rate, with an additional 7 gigawatts expected to come online between 2022 and 2027. With federal pressure to meet climate goals, as the harms of climate change continue to impact everybody, legislators are looking to community solar as a method to achieving their states energy policy goals. These new policies that push for low-to-moderate inclusion, coupled with the increase in community solar capacity illustrate a new era for the community solar industry. A number of policies have arisen in the last few months that push for more inclusive practices including the groundbreaking Solar for All program run by the EPA. The research created a “best practice” contract that can then be used, in conjunction with the manuscript and validated study, to pitch the industry on a more inclusive community solar product.

14 SOLAR ENERGY↗
DOE OSTI2022

Impact of Surface Chemistry of Ultrasmall Superparamagnetic Iron Oxide Nanoparticles on Protein Corona Formation and Endothelial Cell Uptake, Toxicity, and Barrier Function

Ultrasmall superparamagnetic iron oxide nanoparticles (USPIONs) have been investigated for biomedical applications, including novel contrast agents, magnetic tracers for tumor imaging, targeted drug delivery vehicles, and magneto-mechanical actuators for hyperthermia and thrombolysis. Despite significant progress, recent clinical reports have raised concerns regarding USPION safety related to endothelial cell dysfunction; however, there is limited information on factors contributing to these clinical responses. The influence of USPION surface chemistry on nanoparticle interactions with proteins may impact endothelial cell function leading to adverse responses. Therefore, the goal of this study was to assess the effects of carboxyl-functionalized USPION (CU) or amine-functionalized USPION (AU) (approximately 30 nm diameter) on biological responses in human coronary artery endothelial cells. Increased protein adsorption was observed for AU compared with CU after exposure to serum proteins. Exposure to CU, but not AU, resulted in a concentration-dependent decrease in cell viability and perinuclear accumulation inside cytoplasmic vesicles. Internalization of CU was correlated with endothelial cell functional changes under non-cytotoxic conditions, as evidenced by a marked decreased expression of endothelial-specific adhesion proteins (eg, vascular endothelial-cadherin and platelet endothelial cell adhesion molecule-1) and increased endothelial permeability. Evaluation of downstream signaling indicated endothelial permeability is associated with actin cytoskeleton remodeling, possibly elicited by intracellular events involving reactive oxygen species, calcium ions, and the nanoparticle cellular uptake pathway. This study demonstrated that USPION surface chemistry significantly impacts protein adsorption and endothelial cell uptake, viability, and barrier function. This information will advance the current toxicological profile of USPION and improve development, safety assessment, and clinical outcomes of USPION-enabled medical products.

Toxicology↗
DOE OSTI2023

Important Factors for the Reliable and Reproducible Preparation of Non-aqueous Electrolyte Solutions for Lithium Batteries

Electrolyte solutions play a crucial role in rechargeable lithium batteries. Driven by an ever-increasing demand for better batteries, more and more stringent performance requirements are being asked of electrolytes. This demand to achieve electrolytes beyond the state-of-the-art has driven an increasing number of publications over the past decade. Nevertheless, a detailed description of electrolyte preparation is frequently missing when reporting new electrolytes for batteries, creating a barrier for others to reproduce important findings. In addition, false or misleading information in a paper may result from unintentional inaccuracies during the electrolyte preparation process. This article highlights important factors for the reliable and reproducible preparation of non-aqueous electrolyte solutions for lithium batteries, with the aim of encouraging researchers to follow more rigorous reporting standards.

Cao, Xia↗
DOE OSTI2025

Geospatial analysis of preterm and small-for-gestational age births in Washington D.C.

Background: This study is based on the recognition that adverse pregnancy outcomes significantly affect maternal and infant health, leading to increased morbidity and mortality. These outcomes are shaped by a complex interplay of individual-level factors—like maternal age and education—and community-level influences, including socio-economic status and access to healthcare. Understanding these determinants is crucial for developing effective public health strategies, especially for marginalized populations, by identifying high-risk areas and informing targeted interventions that address both individual and structural barriers. Methods: We utilized geospatial analysis to explore the association between individual- and community-level factors and adverse pregnancy outcomes, specifically preterm birth (PTB) and small-for-gestational-age (SGA) birthweight in Washington, D.C. We used Empirical Bayes smoothing methods to calculate rates of adverse birth outcomes from 2010 to 2018 at the U.S. Census tract–level. Spatial scan statistics were used to investigate if adverse birth outcomes clustered in specific areas. ANOVA tests were conducted for individual- and community-level factors within identified clusters. Results: Spatial analysis identified significant high-risk clusters for PTB and SGA infants primarily in southeastern Washington, D.C., particularly in Wards 7 and 8. Individuals residing within these clusters experienced a 47% increased risk of PTB (RR = 1.467) and a 56% increased risk of SGA (RR = 1.560) compared to those outside clusters. Space–time analysis revealed temporal variation, with PTB clusters persisting from 2011 to 2014 and SGA clusters extending through 2017. Compared to low-risk clusters, high-risk clusters had younger birthing individuals (mean age ~26.5 vs. ~33 years), lower maternal college degree attainment (~20% vs. ~80%), higher rates of late or no prenatal care (~16% vs. 11%), and increased prevalence of smoking and hypertension (all P < 0.001). Community-level indicators showed lower median household incomes ($\$40,000$ vs. ~$\$105,000$), greater poverty (~16% vs. ~7% below $\$10,000$/year), higher public assistance use (~32% vs. ~5%), and reduced healthcare access (greater distances to emergency and specialty care) in high-risk areas (all P < 0.001). Neighborhood deprivation indices were significantly elevated, commutes were longer, and population density was lower in these clusters. These findings highlight that adverse birth outcomes cluster in neighborhoods with pronounced socioeconomic and health disparities. Conclusion: High-risk birth clusters highlight intertwined factors: individual, socio-economic, and geographic. Addressing these requires comprehensive interventions focusing on social and structural determinants of health.

Birth outcomes↗
DOE OSTI2026

Lessons Learned for Transmission Cost Allocation in U.S. Regional Markets

Expanding electric transmission can facilitate generator interconnection and improve grid reliability. Assigning costs for new transmission infrastructure is highly contentious because these costs can have a direct impact on energy prices and ratepayer bills. In this report, we evaluate what factors influence successful transmission cost allocation agreements. Through a review of legal disputes, existing cost allocation practices, and regional case studies, we identify potential strategies to minimize cost allocation disputes for future projects. The report also highlights the processes by which regions can update their cost allocation methods. While we do not consider cost allocation methods currently under development for compliance with FERC Order 1920, the trends and lessons learned identified in this report can inform discussions on effective cost allocation methods to reduce barriers for transmission development.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS1992

The AGARD tip research agenda for Scientific and Technical Information (STI)

The Research Agenda contains three themes: information management, provision of information, and access to information. Provision of information is further divided into two subordinate themes, dissemination and bibliographic control; access to information is also further divided into two subordinate themes, barriers and equity and networking. Each theme or sub-theme was examined from four possible aspects, namely, human resources, quality assurance, cost, and technology. It was concluded that, in fact, a theme or sub-theme need not contain all four aspects.

Blados, Walter R.↗
DOE OSTI2022

Model results and data for Nontechnical Barriers to Geothermal Development

Data included in this submission support the analysis conducted for the report "Nontechnical Barriers to Geothermal Development" which is linked bellow. These data include information about the power purchase agreements (PPAs) analyzed for the report, inputs and model results for the pro forma economic analysis, and outputs from the regression analysis conducted on PPAs comparing geothermal and other power generation technologies.

15 GEOTHERMAL ENERGY↗
NASA NTRS2005

Learning Science Through Visualization

In the context of an introductory physical science course for non-science majors, I have been trying to understand how scientific visualizations of natural phenomena can constructively impact student learning. I have also necessarily been concerned with the instructional and assessment approaches that need to be considered when focusing on learning science through visually rich information sources. The overall project can be broken down into three distinct segments : (i) comparing students' abilities to demonstrate proportional reasoning competency on visual and verbal tasks (ii) decoding and deconstructing visualizations of an object falling under gravity (iii) the role of directed instruction to elicit alternate, valid scientific visualizations of the structure of the solar system. Evidence of student learning was collected in multiple forms for this project - quantitative analysis of student performance on written, graded assessments (tests and quizzes); qualitative analysis of videos of student 'think aloud' sessions. The results indicate that there are significant barriers for non-science majors to succeed in mastering the content of science courses, but with informed approaches to instruction and assessment, these barriers can be overcome.

Chaudhury, S. Raj↗
DOE OSTI2025

Scrambling Signal Modularity in Bottom-up Assembled Synthetic Pseudomonas Consortia Reveals Robust Information Transfer

There is immense potential in crafting synthetic microbial communities for application in human health, agriculture, the environment, and even biomanufacturing where an appropriately constructed consortium can be assembled with tremendous biosynthetic or degradative capabilities. In many of these cases, bacterial signaling serves as a form of intercellular information transfer that guides the collective’s behavior. Such communication is complex, as many signals, signal disruptors, microbial species, physical barriers, and spatiotemporal constraints may be involved. Here, in this work, we demonstrate that a multisignal pathway for molecular information transfer within a consortium of several Pseudomonas spp. can be scrambled (genetically and organizationally) while the original message is still effectively conveyed. Assembled from the bottom up, we have employed two types of signaling molecules (i) a redox active secondary metabolite (rhizospheric signal, phloroglucinol), and (ii) a bacterial quorum sensing signal (3-oxo-C12 acylhomoserine lactone, AI-1). These signals can be intraconverted and acted upon by designated community members. We show how the order in which the signals are received, transduced, and subsequently transmitted can be rearranged with minimal impact on the intended outcome. In the consortial context, we found this messaging structure can be remarkably robust. Inspired by rhizospheric molecular signaling mechanisms, this work provides a conceptual framework for designing signaling and information transfer processes within assembled communities.

Biological and medical sciences↗
NASA NTRS2014

Planetary Science Technology Infusion Study: Findings and Recommendations Status

The Planetary Science Division (PSD) within the National Aeronautics and Space Administrations (NASA) Science Mission Directorate (SMD) at NASA Headquarters sought to understand how to better realize a scientific return on spacecraft system technology investments currently being funded. In order to achieve this objective, a team at NASA Glenn Research Center was tasked with surveying the science and mission communities to collect their insight on technology infusion and additionally sought inputs from industry, universities, and other organizations involved with proposing for future PSD missions. This survey was undertaken by issuing a Request for Information (RFI) activity that requested input from the proposing community on present technology infusion efforts. The Technology Infusion Study was initiated in March 2013 with the release of the RFI request. The evaluation team compiled and assessed this input in order to provide PSD with recommendations on how to effectively infuse new spacecraft systems technologies that it develops into future competed missions enabling increased scientific discoveries, lower mission cost, or both. This team is comprised of personnel from the Radioisotope Power Systems (RPS) Program and the In-Space Propulsion Technology (ISPT) Program staff.The RFI survey covered two aspects of technology infusion: 1) General Insight, including: their assessment of barriers to technology infusion as related to infusion approach; technology readiness; information and documentation products; communication; integration considerations; interaction with technology development areas; cost-capped mission areas; risk considerations; system level impacts and implementation; and mission pull. 2) Specific technologies from the most recent PSD Announcements of Opportunities (AOs): The Advanced Stirling Radioisotope Generator (ASRG), aerocapture and aeroshell hardware technologies, the NASA Evolutionary Xenon Thruster (NEXT) ion propulsion system, and the Advanced Materials Bi-propellant Rocket (AMBR) engine.This report will present the teams Findings from the RFI inputs and the recommendations that arose from these findings. Methodologies on the findings and recommendations development are discussed.

technology infusion↗
DOE OSTI2021

Compressional wave velocity and effective stress in unsaturated soil: Potential application for monitoring moisture conditions in vadose zone sediments

Compressional seismic (P-wave) velocities were measured experimentally at different water potentials and confining pressure states using a variety of sediments collected from the US Department of Energy Hanford Site in southeastern Washington State. P-wave velocity was measured in variably saturated sediments using ultrasonic piezoelectric transducers and water potential was measured with a heat dissipation sensor. We propose a model to relate changes in P-wave velocity to soil stress conditions using an effective stress formulation that includes capillary stress as well as adsorptive stress. We show that compressional wave velocities can be related to water potential and confining stress using a model with five fitted parameters. A single set of parameters provides an excellent fit to data acquired from all of the sediment samples. Under very dry conditions, corresponding to low water potentials, water flow occurs in adsorptive thin films associated with very low unsaturated hydraulic conductivities. The results presented here suggest the utility of seismic methods for establishing low water potential and flow conditions within variably saturated Hanford formation sediments and providing feedback on the performance of mitigation efforts such as soil desiccation and surface infiltration barriers. Seismic methods can provide minimally invasive, three-dimensional information on relevant flow conditions in vadose zone sediments as well as changes that occur over time.

Linneman, Dorothy C.↗
DOE OSTI2022

Macro Analysis to Estimate Electric Vehicles Fast-Charging Infrastructure Requirements in Small Urban Areas

Electric vehicles (EVs) are known to reduce emissions and fossil fuel dependency. However, the limited range, long charging time, and inadequate charging infrastructure have hampered the adoption of EVs. The current EV charging infrastructure planning studies and tools require detailed information, extensive resources, and skills that can be a significant barrier to urban areas for finding the required charging infrastructure to support a targeted EV market share. This study generates regression models to estimate the number of direct current fast charging stations and the chargers to support the EV charging demand for urban areas. These models provide macro-level estimates of the required infrastructure investment in urban areas, which can be easily implemented by policy-makers and city planners. This study incorporates data obtained from applying a disaggregate optimization-based charger placement model, developed recently by the same authors, for multiple case studies to generate the required data to calibrate the macro-level models, in the state of Michigan. This simulated data set includes the number of charging stations and chargers for each market share, technology advancement scenario, and the transportation network topology. The results show that the number of charging stations reduces with battery size and charging power and increases with EV market share and the road network lane length. The number of chargers reduces with charging power, whereas it increases with battery size, EV market share, and vehicle miles traveled in the system. The model developed here can be applied to any state having urban characteristics and weather conditions similar to Michigan.

Engineering↗
NASA NTRS1995

An electron tunneling study of superconductivity in amorphous Sn(sub 1-x)Cu(sub x) thin films

The amorphous phase of Sn would have a superconducting transition temperature near 8 K, much higher than that of crystalline Sn with T(sub c) = 3.5 K. To obtain the amorphous phase, however, it is necessary to use a Sn alloy, usually Cu, and quench condense the alloy films onto a liquid He temperature substrate. Alloying with Cu reduces the superconducting transition temperature almost linearly with Cu concentration with an extrapolation of T(sub c) to zero for x = 0.85. Analysis of the tunneling characteristics between a normal metal electrode with an insulating barrier and superconducting amorphous Sn-Cu films provides detailed information on the changes in the electron-phonon coupling which determines T(sub c) in these alloys. The change from very strong electron-phonon coupling to weak-coupling with the increase in Cu content of amorphous Sn-Cu alloys for the range 0.08 is less than or equal to x is less than or equal to 0.41 is presented and discussed in terms of theories of electron-phonon coupling in disordered metals.

Naugle, D. G.↗
NASA NTRS2012

Simulation Tool for Dielectric Barrier Discharge Plasma Actuators at Atmospheric and Sub-Atmospheric Pressures: SBIR Phase I Final Report

This report is the final report of a SBIR Phase I project. It is identical to the final report submitted, after some proprietary information of administrative nature has been removed. The development of a numerical simulation tool for dielectric barrier discharge (DBD) plasma actuator is reported. The objectives of the project were to analyze and predict DBD operation at wide range of ambient gas pressures. It overcomes the limitations of traditional DBD codes which are limited to low-speed applications and have weak prediction capabilities. The software tool allows DBD actuator analysis and prediction for subsonic to hypersonic flow regime. The simulation tool is based on the VORPAL code developed by Tech-X Corporation. VORPAL's capability of modeling DBD plasma actuator at low pressures (0.1 to 10 torr) using kinetic plasma modeling approach, and at moderate to atmospheric pressures (1 to 10 atm) using hydrodynamic plasma modeling approach, were demonstrated. In addition, results of experiments with pulsed+bias DBD configuration that were performed for validation purposes are reported.

Likhanskii, Alexandre↗
DOE OSTI2023

Understanding Emerging Building Technologies in Federal Performance Contracting Markets

Every year, federal technology evaluation programs test and assess the performance of building technologies that are being considered for wider deployment in federal facilities. Despite these investments in technology validation, many of the technologies evaluated by federal programs struggle to achieve broad penetration into the federal performance contracting market. This report contains the results of a market-research survey conducted by the National Renewable Energy Laboratory to understand barriers to the wider adoption of validated building technologies in the federal performance contracting market and how this information can be used to increase their deployment. The initial phase of this research focuses on the energy service company community and the barriers they perceive to wider adoption of these evaluated technologies. The report ends with an examination of recommendations for how the U.S. Department of Energy's Federal Energy Management Program can assist agencies in deploying emerging building technologies through energy savings performance contracts.

25 ENERGY STORAGE↗
DOE OSTI2025

High Mobility and Electrostatics in GeSn Quantum Wells With SiGeSn Barriers

GeSn is an emerging material with potential applications in next‐generation integrated optoelectronics and quantum information processing. While GeSn/SiGeSn quantum wells exhibit promising optical properties, their electrical transport characteristics and governing electrostatics in gated structures remain unexplored. Heterostructure field‐effect transistors are fabricated using GeSn/SiGeSn quantum wells and electronic transport properties of 2D holes are characterized. At 2 K, heterostructure field‐effect transistors with well/barrier compositions of Ge 0.945 Sn 0.055 /Si 0.03 Ge 0.93 Sn 0.04 and Ge 0.9 Sn 0.1 /Si 0.017 Ge 0.927 Sn 0.056 , show peak mobilities of 9000 and 19 000 cm 2 /Vs, respectively, the latter setting a record for the highest mobility reported for GeSn quantum wells with a Sn concentration around 6 % or greater. Remarkably, at low carrier densities, devices with a SiGeSn barrier exhibit mobilities several times higher than previously reported for GeSn quantum wells with a Ge barrier. This higher mobility contrasts with the expectation that alloy scattering from the barrier would reduce carrier mobility. Two mechanisms based on atom probe tomography data analyses are proposed: i) unintentionally improved SiGeSn/GeSn interface and/or ii) reduced alloy scattering from short‐range order. Significant current–voltage hysteresis is observed, with the effective threshold gate voltage shifting by more than 5 V, attributed to non‐equilibrium trapped charge at various interfaces within the SiGeSn heterostructure.

GeSn↗