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Results for “ROLLING”
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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Tuning of friction noise by accessing the rolling-sliding option
Not Available
Proactive Rolling-Horizon-Based Scheduling of Hydrogen Systems for Resilient Power Grids
Not provided.
National variability in Americans’ COVID-19 protective behaviors: Implications for vaccine roll-out
Protective behaviors such as mask wearing and physical distancing are critical to slow the spread of COVID-19, even in the context of vaccine scale-up. Understanding the variation in self-reported COVID-19 protective behaviors is critical to developing public health messaging. The purpose of the study is to provide nationally representative estimates of five self-reported COVID-19 protective behaviors and correlates of such behaviors. In this cross-sectional survey study of US adults, surveys were administered via internet and telephone. Adults were surveyed from April 30-May 4, 2020, a time of peaking COVID-19 incidence within the US. Participants were recruited from the probability-based AmeriSpeak® national panel. Brief surveys were completed by 994 adults, with 73.0% of respondents reported mask wearing, 82.7% reported physical distancing, 75.1% reported crowd avoidance, 89.8% reported increased hand-washing, and 7.7% reported having prior COVID-19 testing. Multivariate analysis (p critical value .05) indicates that women were more likely to report protective behaviors than men, as were those over age 60. Respondents who self-identified as having low incomes, histories of criminal justice involvement, and Republican Party affiliation, were less likely to report four protective behaviors, though Republicans and individuals with criminal justice histories were more likely to report having received COVID-19 testing. The majority of Americans engaged in COVID-19 protective behaviors, with low-income Americans, those with histories of criminal justice involvement, and self-identified Republicans less likely to engage in these preventive behaviors. Culturally competent public health messaging and interventions might focus on these latter groups to prevent future infections. These findings will remain highly relevant even with vaccines widely available, given the complementarities between vaccines and protective behaviors, as well as the many challenges in delivering vaccines.
Hot Rolling Scrap Reduction through Edge Cracking and Surface Defects Control
The design of future aircraft must address the combined demands for fuel efficiency, reduced emissions and lower operating costs. One contribution to these goals is weight savings through the development of new alloys and design techniques for airframe structures. This research contributes to the light-weighting through fabrication of monolithic components from advanced aluminum alloys by making a link between alloy processing history and in-service performance. Specifically, this research demonstrates the link between growing cracks with features of the alloy microstructure that follow from thermo-mechanical processing. This is achieved through a computer model of crack deviation. The model is validated against experimental data from production scale aluminum alloy plate, and demonstration of the effect of changes in processing history on crack growth is made. The model is cast in the open-source finite element code WARP3D, which is freely downloadable and well documented. This project provides benefit along several avenues. First, the technical contribution of the computer model offers the materials engineer a critical means of providing guidance both upstream, to process tuning to achieve optimal properties, and downstream, to enhance fault tolerance. Beyond the fuel savings and emissions reduction inherent in the light-weighting of aircraft structures, improved fault tolerance addresses demands for longer inspection intervals over baseline, and a lower life cycle cost.
Elevated temperature tensile tests on DU-10Mo rolled foils
Tensile mechanical properties for uranium-10 wt.% molybdenum (U–10Mo) foils are required to support modeling and qualification of new monolithic fuel plate designs. It is expected that depleted uranium-10 wt% Mo (DU–10Mo) mechanical behavior is representative of the low enriched U–10Mo to be used in the actual fuel plates, therefore DU-10Mo was studied to simplify material processing, handling, and testing requirements. In this report, tensile testing of DU-10Mo fuel foils prepared using four different thermomechanical processing treatments were conducted to assess the impact of foil fabrication history on resultant tensile properties.
Elevated Temperature Tensile Tests on DU10Mo Rolled Foils TEV-2194 R1
This work was conducted under PLN-4560, “GTRI Mechanical Property Characterization Test Plan,” which contains additional requirements and instructions for testing. The following report presents details of the testing system, testing methods, and mechanical properties determined from the test data.
Reasons to resist rolling and twisting in granular materials.
Abstract not provided.
Granular rheology with sliding rolling and twisting friction.
Abstract not provided.
Shaded fraction and backtracking in single-axis trackers on rolling terrain
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SCORE (Synthesis of COnsists as Rolling Energy microgrids) (Final Technical Report)
The SCORE toolset is an open source, web-based application to assess the impact of new powering technologies on railroad performance, specifically technologies capable of both putting power into the rail (motive force) and taking power from the rail (regeneration). SCORE’s primary goal is generate trade studies to analyze different powering and train make-up options to minimize energy usage and greenhouse gas generation. At the core of generating these trade spaces is calculating the optimal powering policy for the train given the makeup of the train, the route, and time constraints. This paper presents details on the algorithms used in SCORE to compute this powering policies that is fast and accurate, discusses its implementation in an Energy-Longitudinal Train Dynamics (E-LTD) model, compares it to naïve approaches, and demonstrates its use across a variety of train/route pairs.
Characterization of point-source transient events with a rolling-shutter compressed-sensing system (presentation)
Slides of presentation I'll be giving at SPIE'24: Optics and Photonics.
Modeling and experimental investigation of the dynamics of a spherical Transforming Roving Rolling Explorer (TRREx) prototype
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INFLUENCE OF AUTOMATIC CONTROL OF ROLL COUPLING AND PITCH-UP ON TAIL LOADS
Stability & control of aircraft - aerodynamic loading
Coriolis effects during pitch and roll maneuvers in a piloted flight simulator
Effect of suprathreshold value of Coriolis acceleration on pilot of flight simulator - reference to perception of illusory motion and position in space
Coriolis effects during pitch and roll maneuvers in a piloted flight simulator.
Pilot perception measurements of illusory motion and position in space while undergoing suprathreshold values of Coriolis acceleration
The rolling power of two wing-aileron configu- rations as affected by flexibility
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