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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 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Lewis Research Center studies of multiple large wind turbine generators on a utility network

A NASA-Lewis program to study the anticipated performance of a wind turbine generator farm on an electric utility network is surveyed. The paper describes the approach of the Lewis Wind Energy Project Office to developing analysis capabilities in the area of wind turbine generator-utility network computer simulations. Attention is given to areas such as, the Lewis Purdue hybrid simulation, an independent stability study, DOE multiunit plant study, and the WEST simulator. Also covered are the Lewis mod-2 simulation including analog simulation of a two wind turbine system and comparison with Boeing simulation results, and gust response of a two machine model. Finally future work to be done is noted and it is concluded that the study shows little interaction between the generators and between the generators and the bus.

Gilbert, L. J.↗
DOE OSTI2022

Decarbonizing the Building Sector: A Human-Centered Study Focused on Small/Light Commercial Building Energy Equity

Decarbonization of the building sector is no small feat; buildings account for 40% of primary energy consumption, and fossil-fuel combustion in buildings leads to roughly 30% of total greenhouse gas emissions. Energy efficiency, electrification and smart technologies are fundamental strategies to reduce consumption and shift away from fossil-fuel use in buildings. This energy transition carries significant societal risks unless the shift is carried out with equity and justice as a top priority. Low-income, vulnerable and communities of color have higher energy burdens compared to affluent populations. Furthermore, systemic racism and historic exclusionary policies have resulted in increased risks (environmental, climatic, economic, and social) to low-income and communities of color, and underserved communities often do not have financial resources for, or access to, advanced building technologies. The U.S. Department of Energy is funding research to characterize and develop solutions to the challenges of equity and justice that complicate the ability of communities to contribute to goals for decarbonization. Our project has a specific focus on small commercial buildings and the businesses that occupy them. Significantly less is known about the burdens and risks these businesses experience or the challenges they face in pursuing decarbonization, or how those are affected by income and race, in comparison to research on energy equity and justice for diverse households. The project team includes the Pacific Northwest National Laboratory, Arizona State University and Clark Atlanta University. Researchers are conducting semi-structured interviews with small business owners in underserved communities in Phoenix and Atlanta, followed by a survey distributed to the larger community to learn more about the equity and justice issues that communities with different racial, economic, and cultural backgrounds face. Results will help inform an actionable and replicable framework for engaging small commercial building owners/operators to catalyze the reduction of energy burdens and increase equity.

Antonopoulos, Chrissi A.↗
NASA NTRS1980

A Continuation of Base-line Studies for Environmentally Monitoring Space Transportation Systems at John F. Kennedy Space Center: Chemical Studies of Rainfall and Soil Analysis - Volume 2

The results of a study which was designed to monitor, characterize, and evaluate the chemical composition of precipitation (rain) which fell at the Kennedy Space Center, Florida (KSC) during the period July 1977 to March 1979 are reported. Results which were obtained from a soil sampling and associated chemical analysis are discussed. The purpose of these studies was to determine the environmental perturbations which might be caused by NASA space activities.

Madsen, B. C.↗
DOE OSTI2022

The safety of pranlukast and montelukast during the first trimester of pregnancy: A prospective, two‐centered cohort study in Japan

Abstract For leukotriene receptor antagonists (LTRAs), especially pranlukast, safety data during pregnancy is limited. Therefore, we conducted a prospective, two‐centered cohort study using data from teratogen information services in Japan to clarify the effects of LTRA exposure during pregnancy on maternal and fetal outcomes. Pregnant women who being counseled on drug use during pregnancy at two facilities were enrolled. The primary outcome of this study was major congenital anomalies. The incidence of major congenital anomalies in women exposed to montelukast or pranlukast during the first trimester of pregnancy was compared with that of controls. Logistic regression analysis was performed to analyze the effects of maternal LTRA use during the first trimester of pregnancy on major congenital anomalies. The outcomes of 231 pregnant women exposed to LTRAs (montelukast n = 122; pranlukast n = 106; both n = 3) and 212 live births were compared with those of controls. The rate of major congenital anomalies in the LTRA group was 1.9%. Multivariable logistic regression analysis revealed that LTRA exposure was not a risk factor for major congenital anomalies (adjusted odds ratio, 0.78; 95% confidence interval, 0.23–2.05; p = 0.653). In addition, no significant difference was detected in stillbirth, spontaneous abortion, preterm birth, and low birth weight between the two groups. The present study revealed that montelukast and pranlukast were not associated with the risk of major congenital anomalies. Our findings suggest that LTRAs could be safely employed for asthma therapy during pregnancy.

Hatakeyama, Shiro↗
NASA NTRS1992

Process comparison study. MSFC Center Director's Discretionary Fund (CDDF)

A process comparison study was conducted using four different advanced manufacturing techniques to fabricate a composite solid rocket booster systems tunnel cover. Costs and labor hours were tracked to provide the comparison between the processes. A relative structural comparison of the components is also included. The processes utilized included filament winding, pultrusion, automated tape laying, and thermoplastic thermoforming. The hand layup technique is also compared. Of the four advanced processes evaluated, the thermoformed thermoplastic component resulted in the least total cost. The automated tape laying and filament winding techniques closely followed the thermoplastic component in terms of total cost; and, these techniques show the most promise for high quality components and lower production costs. The pultruded component, with its expensive tooling and material requirements, was by far the most expensive process evaluated, although the results obtained would not be representative of large production runs.

Golden, T.↗
NASA NTRS2002

The Center for Star Formation Studies

The Center for Star Formation Studies, a consortium of scientists from the Space Science Division at Ames and the Astronomy Departments of the University of California at Berkeley and Santa Cruz, conducts a coordinated program of theoretical research on star and planet formation. Under the directorship of D. Hollenbach (Ames), the Center supports postdoctoral fellows, senior visitors, and students; meets regularly at Ames to exchange ideas and to present informal seminars on current research; hosts visits of outside scientists; and conducts a week-long workshop on selected aspects of star and planet formation each summer.

Hollenbach, D.↗
NASA NTRS2000

A Multi-Center Controlled Study of the Acute and Chronic Effects of Cooling Therapy for MS

To determine the acute and chronic effects of cooling therapy on patients with MS using objective functional performance measures and self-assessed measures of fatigue. Cooling demyelinated nerves can reduce conduction block, potentially improving symptoms of MS. Significant acute and chronic effects of cooling have not been demonstrated in a multi-center, controlled, blinded study using objective measures of neurologic function. Patients (N=84) with definite MS, mild to moderate disability (EDSS less than 6.0), and self-reported heat sensitivity were enrolled at 5 study sites. Acute effects of cooling were assessed by randomly assigning subjects to high-dose or low-dose cooling for one hour using an active cooling vest and cap (Life Enhancement Technologies, Santa Clara, CA). Settings were individualized to maintain the cooling garments at 55 F for the high-dose treatment and 70 F for the low-dose treatment. Both patients and examining investigators were blinded to treatment assignments. The MSFC and visual acuity/contrast sensitivity were assessed before and 30 minutes after treatment. The following week, subjects had an identical visit with the alternate cooling treatment. Chronic effects of cooling were assessed by randomly assigning the same subjects to unblinded daily home cooling or observation for 4 weeks. All subjects completed the Rochester Fatigue Diary (RFD) twice weekly and subjective measures of strength, cognition, and energy level daily. At the end of the period, subjects completed the Modified Fatigue Impact Scale (MFIS) and underwent another high-dose cooling session with assessment of the MSFC and vision. After a one-week washout period, subjects crossed over to the alternate 4-week treatment. Oral temperatures were reduced with both acute treatments (0.8 +/- .06 F, high and 0.5 +/- .06 F, low). While mean MSFC did not change significantly during individual cooling sessions, post hoc analysis pooling the 3 high-dose cooling sessions revealed an improvement in MSFC scores (acute phase 0.064 +/- 0.020, p = 0.0013; chronic phase 0.044 +/- 0.021, p = 0.0368) from before to after cooling. The change in MSFC scores during the acute cooling sessions was not related to the extent of change in oral temperatures. Both the RFD score and the MFIS indicate a significantly lower fatigue level during the cooling month compared to observation (RFD, 2.53 +/- 0.83,p = 0.0033; MFIS 7.63 +/- 1.56, p = 0.0001).

Luna, Bernadette↗
NASA NTRS2011

Heavy Lift Vehicle (HLV) Avionics Flight Computing Architecture Study

A NASA multi-Center study team was assembled from LaRC, MSFC, KSC, JSC and WFF to examine potential flight computing architectures for a Heavy Lift Vehicle (HLV) to better understand avionics drivers. The study examined Design Reference Missions (DRMs) and vehicle requirements that could impact the vehicles avionics. The study considered multiple self-checking and voting architectural variants and examined reliability, fault-tolerance, mass, power, and redundancy management impacts. Furthermore, a goal of the study was to develop the skills and tools needed to rapidly assess additional architectures should requirements or assumptions change.

Hodson, Robert F.↗
NASA NTRS2012

Stress Analysis and Testing at the Marshall Space Flight Center to Study Cause and Corrective Action of Space Shuttle External Tank Stringer Failures

After the launch scrub of Space Shuttle mission STS-133 on November 5, 2010, large cracks were discovered in two of the External Tank intertank stringers. The NASA Marshall Space Flight Center, as managing center for the External Tank Project, coordinated the ensuing failure investigation and repair activities with several organizations, including the manufacturer, Lockheed Martin. To support the investigation, the Marshall Space Flight Center formed an ad-hoc stress analysis team to complement the efforts of Lockheed Martin. The team undertook six major efforts to analyze or test the structural behavior of the stringers. Extensive finite element modeling was performed to characterize the local stresses in the stringers near the region of failure. Data from a full-scale tanking test and from several subcomponent static load tests were used to confirm the analytical conclusions. The analysis and test activities of the team are summarized. The root cause of the stringer failures and the flight readiness rationale for the repairs that were implemented are discussed.

Wingate, Robert J.↗
DOE OSTI2025

Craig Energy Center Feasibility Study

Tri-State Generation and Transmission Association Inc. (“Tri-State”) provides wholesale electric power to its member cooperatives and public power districts that collectively deliver electricity to more than a million consumers in Colorado, Nebraska, New Mexico and Wyoming. The Craig Power Station has been an integral part of Tri-State’s dispatchable generation fleet that ensures an affordable, reliable and resilient energy supply for its members. The ownership of the Craig Station Unit 1&2 is a collaborative between Tri-State, Salt River Project Agricultural Improvement and Power District, Platte River Power Authority, PacifiCorp, and Public Service Company of Colorado and is known as the Yampa Project. Tri-State owns all of Craig Unit 3 and is the operator of all three units. All three of the Craig units have planned retirement dates that will not extend beyond 2028 and Tri-State Generation wanted to evaluate carbon-neutral emitting technologies that could provide approximately 300 megawatts (“MWs) of capacity and energy that will be lost after Unit 3 ceases operation, as well as provide a similar level of economic benefits to the Craig community. This report is to serve as a technology feasibility study constrained to the current land area available at the Craig site and was conducted based on the limitations of the region.

25 ENERGY STORAGE↗
NASA NTRS2012

NASA's Marshall Space Flight Center Recent Studies and Technology Developments in the Area of SSA/Orbital Debris

NASA/MSFC has been investigating the various aspects of the growing orbital debris problem since early 2009. Data shows that debris ranging in size from 5 mm to 10 cm presents the greatest threat to operational spacecraft today. Therefore, MSFC has focused its efforts on small orbital debris. Using off-the-shelf analysis packages, like the ESA MASTER software, analysts at MSFC have begun to characterize the small debris environment in LEO to support several spacecraft concept studies and hardware test programs addressing the characterization, mitigation, and ultimate removal, if necessary, of small debris. The Small Orbital Debris Active Removal (SODAR) architectural study investigated the overall effectiveness of removing small orbital debris from LEO using a low power, space-based laser. The Small Orbital Debris Detection, Acquisition, and Tracking (SODDAT) conceptual technology demonstration spacecraft was developed to address the challenges of in-situ small orbital debris environment classification including debris observability and instrument requirements for small debris observation. Work is underway at MSFC in the areas of hardware and testing. By combining off the shelf digital video technology, telescope lenses, and advanced video image FPGA processing, MSFC is building a breadboard of a space based, passive orbital tracking camera that can detect and track faint objects (including small debris, satellites, rocket bodies, and NEOs) at ranges of tens to hundreds of kilometers and speeds in excess of 15 km/sec,. MSFC is also sponsoring the development of a one-of-a-kind Dynamic Star Field Simulator with a high resolution large monochrome display and a custom collimator capable of projecting realistic star images with simple orbital debris spots (down to star magnitude 11-12) into a passive orbital detection and tracking system with simulated real-time angular motions of the vehicle mounted sensor. The dynamic star field simulator can be expanded for multiple sensors (including advanced star trackers), real-time vehicle pointing inputs, and more complex orbital debris images. This system is also adaptable to other sensor optics, missions, and installed sensor testing.

Wiegmann, Bruce M.↗
DOE OSTI2024

The center for nonlinear studies: A personal history

The Center for Nonlinear Studies (CNLS) was an integral part of my scientific career starting as a Postdoctoral Fellow in 1983 up to my tenure as CNLS Director from 2004 to 2015. As such, I experienced a number of scientific phases of CNLS through almost four decades of foundation, evolution, and transition. Throughout this entire interval, the inspiration and influence of David Campbell guided my way. A proper history of CNLS encompassing all of the many contributors to the CNLS story is beyond my means or purpose here. Instead, I present the history as I experienced it. I emphasize the main scientific accomplishments achieved at CNLS over more than 40 years, but I will also attempt to describe and quantify the attributes that made and continue to make the Center for Nonlinear Studies a special institution of remarkable impact and longevity. Throughout its existence, CNLS owes much to the enduring legacy of David Campbell who laid down the foundations and operating principles that have made it so successful.

Ecke, Robert E. (ORCID:0000000177725876)↗
DOE OSTI2022

Effect of localization on photoluminescence and zero-field splitting of silicon color centers

The study of defect centers in silicon has been recently reinvigorated by their potential applications in optical quantum information processing. A number of silicon defect centers emit single photons in the telecommunication O-band, making them promising building blocks for quantum networks between computing nodes. The two-carbon G-center, self-interstitial W-center, and spin-1/2 T-center are the most intensively studied silicon defect centers, yet despite this, there is no consensus on the precise configurations of defect atoms in these centers, and their electronic structures remain ambiguous. Here, in this work, we employ ab initio density functional theory to characterize these defect centers, providing insight into the relaxed structures, band structures, and photoluminescence spectra, which are compared to experimental results. Motivation is provided for how these properties are intimately related to the localization of electronic states in the defect centers. In particular, we present the calculation of the zero-field splitting for the excited triplet state of the G-center defect as the structure is linearly interpolated from the A-configuration to the B-configuration, showing a sudden increase in the magnitude of the D zz component of the zero-field-splitting tensor. By performing projections onto the local orbital states of the defect, we analyze this transition in terms of the symmetry and bonding character of the G-center defect, which sheds light on its potential application as a spin-photon interface.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗