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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 595 records · Page 33
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Situating Green Infrastructure in Context: A Framework for Adaptive Socio‐Hydrology in Cities

Abstract Management of urban hydrologic processes using green infrastructure (GI) has largely focused on storm water management. Thus, design and implementation of GI usually rely on physical site characteristics and local rainfall patterns, and do not typically account for human or social dimensions. This traditional approach leads to highly centralized storm water management in a disconnected urban landscape and can deemphasize additional benefits that GI offers, such as increased property value, greenspace aesthetics, heat island amelioration, carbon sequestration, and habitat for biodiversity. We propose the Framework for Adaptive Socio‐Hydrology (FrASH) in which GI planning and implementation moves from a purely hydrology‐driven perspective to an integrated sociohydrological approach. This allows for an iterative, multifaceted decision‐making process that would enable a network of stakeholders to collaboratively set a dynamic, context‐guided project plan for the installation of GI, rather than a “one‐size‐fits‐all” installation. We explain how different sectors (e.g., governance, nongovernmental organizations, communities, academia, and industry) can create a connected network of organizations that work toward a common goal. Through a graphical Chambered Nautilus model, FrASH is experimentally applied to contrasting GI case studies and shows that this multistakeholder, connected, decentralized network with a coevolving decision‐making project plan results in enhanced multifunctionality, potentially allowing for the management of resilience in urban systems at multiple scales.

Schifman, L. A.↗
DOE OSTI2019

Comorbid conditions in individuals assessed by SPECT: Study of a reference cardiology center in Mexico City

Background: There is an increasing prevalence of comorbidities in patients with ischemic heart disease (IHD) in developing countries. The aim of this work is to assess the prevalence of comorbidities and associated factors for IHD among patients at a reference cardiology center. Design and Methods: This was a cross-sectional study. A complete clinical history which focused on the main comorbidities, previous myocardial infarction, and the main reason of referral was assessed. A single-photon emission computed tomography (SPECT) myocardial perfusion study (MPS) with two protocols was performed. Results: We included 1998 patients, 64.2% male, median age 63 (I.R.: 56–71) years. 1514 (75.8%) subjects had at least one associated comorbidity. The main comorbidity was diabetes (T2D) (772: 38.6%), followed by systemic hypertension (737: 36.9%), smoking (518: 25.9%), and dyslipidemia (517: 25.9%). 806 (40.3%) had histories of previous myocardial infarctions. The main cause of referral was angina (923: 46.2%). We identified 1330 (66.5%) abnormal MPS. 460 (23%) had ischemia, 292 (14.6%) infarction, and 578 (28.9%) ischemia and infarction. Conclusion: An increased prevalence of comorbidities was found in patients who were studied in the Nuclear Cardiology Department (NCD): most of them had traditional risk factors attributable to myocardial infarction. A great percentage were newly diagnosed with both ischemia and infarction.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2024

Comparing the interactions between particulate matter and cloud properties over two populated cities in Texas using WRF-Chem fine-resolution modeling

Accurate modeling of aerosol-cloud interactions is essential for reliable weather and air quality simulations, given their significant impact on precipitation patterns, cloud dynamics, and aerosol distributions. This study employed the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) to examine the impact of enhanced meteorological simulations, achieved through advanced microphysics parameterization supported by data assimilation techniques, on air quality across Texas on August 19 and 20, 2022. We tested four distinct configurations: (1) the Morrison two-moment bulk microphysics scheme, (2) Morrison's with observation nudging, (3) the Spectral Bin Microphysics (SBM), and (4) SBM with observation nudging. While the SBM scheme is known for its detailed representation of aerosol-cloud interactions, our focus was on how improvements in meteorological accuracy translate to more precise air quality simulations. Our findings demonstrated a progressive improvement in simulation accuracy, starting with the Morrison's scheme and further enhanced by adopting the SBM scheme, complemented by incorporating observation nudging. Specifically, the combination of the SBM scheme and the nudging substantially enhanced the model's ability to capture convective precipitation events, as shown by better alignment with NEXRAD radar reflectivity, with R increasing from –0.21 to 0.82, IOA from 0.10 to 0.87, and NMB decreasing from 99% to 34% in Houston. The enhanced meteorology translated into more accurate PM 2.5 concentration simulations, particularly through the more accurate representation of aerosol washout during precipitation events. In Houston, the SBM scheme with nudging improved the model's PM 2.5 simulations significantly, with NMB decreasing from –20% to 5% and IOA improving from 0.43 to 0.61. In San Antonio, improvements were also notable, with NMB improved from –27% to –22%, R increased from 0.48 to 0.82, and IOA increased from 0.66 to 0.86. Furthermore, our results underscore the crucial role of accurate meteorological simulations in refining our understanding of aerosol behaviors in relation to precipitation patterns, directly enhancing the reliability and effectiveness of air quality modeling.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

A novel method for co-optimizing battery sizing and charging strategy of battery electric bus fleets: An application to the city of Paris

Battery-electric buses (BEBs) are a promising technology for replacing diesel buses and reducing their environmental burden. However, their charging process can take several hours, depending on the charging technique and strategy, making them susceptible to schedule disruptions. Furthermore, the selection of the charging strategy and battery size can increase the total capital investment and operational expenses of a BEB fleet, which is a major obstacle to its adoption. Therefore, to minimize the total cost of ownership (TCO) and prevent schedule disruptions, it is essential to establish a well-defined approach to determine an appropriate battery size and charging strategy for BEB fleets. This paper presents a method for reducing the TCO of BEB by determining the optimal battery size and charging strategy for each bus while satisfying operating constraints. The method involves a two-step optimization algorithm that uses Dynamic Programming and Genetic Algorithm. Further, the study applies this approach to the bus fleet serving line 21 in Paris and generates the optimal battery sizing, charging strategy, and required charging infrastructure. The results indicate that 100 kWh batteries offer the best trade-off between capital and operational expenditure for the fleet deployment if used with 65–85 kW chargers at bus terminals.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2018

Air pollution and emergency department visits for respiratory diseases: A multi-city case crossover study

Highlights: • Extensive research exists on the effects of ambient air pollution on respiratory diseases. • Emergency department visits for respiratory diseases increase after days with higher concentrations of air pollution. • Ambient pollution, even at low concentrations, appear to adversely affect the respiratory system. Increasing evidence suggests that ambient air pollution is a major risk factor for both acute and chronic respiratory disease exacerbations and emergencies. The objective of this study was to determine the association between ambient air pollutants and emergency department (ED) visits for respiratory conditions in nine districts across the province of Ontario in Canada. Health, air pollutant (PM{sub 2.5}, NO{sub 2}, O{sub 3}, and SO{sub 2}), and meteorological data were retrieved from April 2004 to December 2011. Respiratory diseases were categorized as: chronic obstructive pulmonary disease (COPD, including bronchiectasis) and acute upper respiratory diseases. A case-crossover design was used to test the associations between ED visits and ambient air pollutants, stratified by sex and season. For COPD among males, positive results were observed for NO{sub 2} with lags of 3–6 days, for PM{sub 2.5} with lags 1–8, and for SO{sub 2} with lags of 4–8 days. For COPD among females, positive results were observed for O{sub 3} with lags 2–4 days, and for SO{sub 2} among lags of 3–6 days. For upper respiratory disease emergencies among males, positive results were observed for NO{sub 2} (lags 5–8 days), for O{sub 3}, (lags 0–6 days), PM{sub 2.5} (all lags), and SO{sub 2} (lag 8), and among females, positive results were observed for NO{sub 2} for lag 8 days, for O{sub 3}, PM{sub 2.5} among all lags. Our study provides evidence of the associations between short-term exposure to air pollution and increased risk of ED visits for upper and lower respiratory diseases in an environment where air pollutant concentrations are relatively low.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

The burden of ischemic heart disease related to ambient air pollution exposure in a coastal city in South China

Highlights: • Burden of ischemic heart disease related to PM{sub 2.5}, SO{sub 2} and NO{sub 2} were estimated. • Stronger impacts of gaseous pollutants versus particulate matter were found. • SO{sub 2} exposure was positively associated with YLL in widowed group. Air pollution is considered one of the most important risk factors for ischemic heart disease (IHD), which is a major public health concern. The disease burden of IHD has continued to rise in China in the past two decades. However, epidemiological studies examining the associations between air pollution and IHD have been scarce in China, and the only studies were conducted in severe air pollution areas, where air pollution levels seriously exceed the World Health Organization Air Quality Guidelines. Whether the influence of air pollution on IHD in areas with relatively low levels of air pollution differs from the influence of high pollution levels in heavily studied areas was unknown until now. Furthermore, the estimation of the disease burden of IHD related to air pollution has been very limited.

54 ENVIRONMENTAL SCIENCES↗