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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 253 records · Page 14

1998 Dallas-Fort Worth Travel Survey

The 1998 Dallas-Fort Worth House Travel Survey accomplished two main goals: updating existing data for the North Central Texas Council of Governments regional travel demand models and providing new data to permit the models to be upgraded. The survey encompassed households within the Consolidated Metropolitan Statistical Area of Dallas-Fort Worth. A total of 4,641 households provided complete information. The survey revealed households' travel behavior preference with the collection of information about household characteristics and travel using a unique "travel as an activity" approach.

1Hz data↗

1999 Dallas-Fort Worth Travel Survey

The 1999 Dallas-Fort Worth House Travel Survey accomplished two main goals: updating the existing data for the North Central Texas Council of Governments regional travel demand models and providing new data to permit the models to be upgraded. The survey encompassed households within the Consolidated Metropolitan Statistical Area of Dallas-Fort Worth. A total of 4,641 households provided complete information. The survey revealed households' travel behavior preference with the collection of information about household characteristics and travel using a unique "travel as an activity" approach.

1Hz data↗

2000 Evansville Household Travel Survey

The Evansville Metropolitan Planning Organization conducted a household travel survey in 2000. This study aimed to produce a detailed analysis of travel behavior for the residents of the Evansville Metropolitan Area. The survey contains data from 1,737 participating households. From participants' travel records, a total of 20,096 trips were reported by 4,069 people for a 24-hour period.

1Hz data↗

1996 Tampa Bay Regional Travel Survey

This study was conducted on behalf of the Florida Department of Transportation. The purpose of the survey was to understand day-to-day travel across the Tampa Bay region. Demographic, socioeconomic, and travel data were gathered from 5,349 households that participated in the study, and a total of 31,465 trips were recorded.

1Hz data↗

1993 Tucson Household Travel Survey

The Arizona Department of Transportation (ADOT) conducted a Tucson Household Travel Survey in 1993. ADOT conducts such surveys every five to seven years, providing an essential snapshot of transportation behaviors and trends by asking how members of a household get around on a single day. The answers helped state, local, and federal officials decide when, where, and how to invest limited transportation funding to improve roads, public transportation, sidewalks, bike paths, and more. Demographic, socioeconomic, and travel information was gathered from 4,564 participants associated with 1,913 households. Participants received travel logs to record where members of their household went on an assigned travel day.

1Hz data↗

2000 Tucson Household Travel Survey

The Arizona Department of Transportation (ADOT) conducted a Tucson Household Travel Survey in 2000. ADOT conducts such surveys every five to seven years, providing an essential snapshot of transportation behaviors and trends by asking how members of a household get around on a single day. The answers helped state, local, and federal officials decide when, where, and how to invest limited transportation funding to improve roads, public transportation, sidewalks, bike paths, and more. Demographic, socioeconomic, and travel information was gathered from 4,882 participants associated with 2,076 households. Participants received travel logs to record where members of their household went on an assigned travel day.

1Hz data↗

1970 Home Interview Survey

The 1970 Home Interview Survey was conducted by Twin Cities Metropolitan Council, Saint Paul. This database was used to develop mathematical models to predict future regional travel patterns, which were used to develop appropriate regional transportation policies, plans, and programs. The 1970 survey did not specifically include walking or bicycling as options in the travel diary; instead, these trips are included in a broad “other” category.

1Hz data↗

Unveiling Sea Quark Dynamics: Measuring Sivers Asymmetry with Polarized Target at SpinQuest

SpinQuest is a cutting-edge, high-luminosity Drell-Yan experiment utilizing polarized hy- drogen and deuterium targets to measure the Sivers asymmetry for the light sea quarks in the nucleon. Detecting a nonzero Sivers asymmetry would provide clear evidence for nonzero or- bital angular momentum of sea quarks. The Sivers asymmetry presents itself as an azimuthal asymmetry in the production of virtual photons via the Drell-Yan process, and SpinQuest will be able to measure this asymmetry using the existing SeaQuest dimuon spectrometer. In addi- tion to making measurements sensitive to the sea quark Sivers function, we will also measure the azimuthal asymmetry in the production of J/ψ particles, which is sensitive to the gluon Sivers function. Additionally, observing a sign change in the Sivers asymmetry between this measurement and future measurements at the Electron-Ion Collider would be a test of a funda- mental prediction of Quantum Chromodynamics. In this poster we will review the physics and technology underpinning the experiment.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Advancing Grid Resilience through Smart Charge Management: Findings from Maryland’s Pilot

This report presents research findings from a four-year Smart Charge Management (SCM) pilot program conducted by Maryland’s largest electric utilities—Baltimore Gas and Electric (BGE), Potomac Electric Power Company (Pepco), and Delmarva Power & Light (DPL)—to evaluate strategies for optimizing electric vehicle (EV) charging loads and enhancing grid stability. Supported by the U.S. Department of Energy (DOE), Argonne National Laboratory collaborated with all project partners and examined the effectiveness of Time-of-Use (TOU) and Load Balancing (LB) strategies in managing peak demand, deferring costly infrastructure upgrades, and reducing grid constraints at the feeder level.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Relations between Shot Noise, Gain Bandwidth, and Saturation of Instabilities

There are numerous instabilities present in charged particle beams that undergo exponential growth and reach saturation. In various applications, such as free-electron lasers or micro-bunching light sources, achieving saturation is desirable. Conversely, there are applications where these instabilities are utilized as linear broad-band amplifiers for signals embedded in the charged beam. In the latter scenario, the saturation of an instability induces non-linear distortions in the imprinted signal, thereby limiting the useful range of such amplifiers. Accurate evaluation of these instabilities necessitates a complete and comprehensive modeling approach that includes shot noise within the beam. Unfortunately, such modeling is not always feasible or practical. In this paper, we introduce a methodology utilizing the frequency and bandwidth of the instability as key parameters. Through this, we derive an estimation for the range of linear instability growth. Our derivation is conducted in a model-independent manner, making it applicable to a broad spectrum of instabilities. To validate our approach, we employ established and thoroughly benchmarked simulations with a free electron laser (FEL) code as well as self-consistent 3-dimensional simulation of plasma-cascade instability using code SPACE.

43 PARTICLE ACCELERATORS↗

ComStock Measure Documentation: Thermostat and Lighting Control for Load Shedding

This report describes the modeling methodology for an upgrade package of two end-use savings shape measures - Thermostat Control for Load Shedding and Lighting Control for Load Shedding - and briefly introduces key results. The package combines thermostat control for load shedding and lighting control for load shedding measures to reduce the HVAC and lighting load during the building's electricity peak window every weekday. The measure takes daily peak load schedule inputs generated by the method "Dispatch Schedule Generation" described in the "Supplemental Documentation: Dispatch Schedule Generation for Demand Flexibility Measures" to determine the start and end times of the predicted peak window, and then relaxes the thermostat setpoints and dims the lighting level from the original schedules during the peak window to reduce the peak demand. The measure is applicable to (large, medium and small) offices, warehouses, and primary and secondary schools, which correspond to approximately 68% of the stock floor area of commercial buildings in ComStock analysis. The measure demonstrates 3%-10% daily peak demand reduction performance for applicable buildings, and 0.97% total site energy savings (0 trillion British thermal units [TBtu]) for the U.S. commercial building stock modeled in ComStock.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Upcycling Real‐World Post‐Consumer Polyolefins Plastics Into Light Olefins Via Microwave‐Assisted Processing

The rapid accumulation of plastic waste, particularly post-consumer polyolefins (POs) pose severe environmental and economic challenges worldwide. Recycling of post-consumer POs remains inefficient due to difficulties in separating mixed plastics, complex additives compositions, and high processing costs, resulting in recycling rates of less than 9%. To address these critical issues, this study utilized an innovative microwave-assisted catalytic upcycling approach for the efficient upcycling of complex post-consumer POs mixtures into valuable light olefins. Using the microwave-assisted catalytic upcycling approach, gas yields reached up to 80 wt.% from post-consumer POs mixtures, accompanied by a high selectivity (>70 wt.%) toward valuable light olefins. The upcycling of POs under microwave conditions is fully invested, including additives in real-word plastics, mixtures of different POs, reusability of catalyst, and more. The microwave-assisted catalytic upcycling approach offers an efficient, scalable, and cost-effective solution for upcycling post-consumer plastic mixtures, thereby advancing the principles of a circular economy.

42 ENGINEERING↗

Minimizing Electric Lighting Use With LASSI Lighting Controls in Controlled Environment Agriculture

The majority of energy use in controlled environment agriculture is typically from electric lighting. Certain lighting controls can help minimize the energy required in these operations. This analysis simulates a greenhouse with different types of lighting controls in different U.S. climates to explore the effects of the lighting controls on energy use.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

ComStock Measure Documentation: Thermostat and Lighting Control for Load Shedding + Photovoltaics With 40% Rooftop Coverage

This report describes the modeling methodology for an upgrade package of two end-use savings shape measures - Thermostat Control for Load Shedding and Lighting Control for Load Shedding - and briefly introduces key results. The package combines thermostat control for load shedding, lighting control for load shedding, and PV with 40% rooftop coverage measures to reduce the net building load during the building's electricity peak window every weekday. The measure takes daily peak load schedule inputs generated by the method "Dispatch Schedule Generation" described in the "Supplemental Documentation: Dispatch Schedule Generation for Demand Flexibility Measures" to determine the start and end times of the predicted peak window, and then relaxes the thermostat setpoints and dims the lighting level from the original schedules during the peak window to reduce the peak demand, while applying the fixed rooftop PV application for onsite electricity generation. The measure is applicable to (large, medium and small) offices, warehouses, and primary and secondary schools, which correspond to approximately 68% of the stock floor area of commercial buildings in ComStock analysis. The measure demonstrates 5%-15% daily peak demand reduction performance for applicable buildings, and around 1% total site energy savings (0 trillion British thermal units [TBtu]) for the U.S. commercial building stock modeled in ComStock.

14 SOLAR ENERGY↗

Reference Piping and Instrumentation Diagrams for Heat Transport Systems for Methanol Plants

This report aims to bridge the gap between advanced nuclear reactor vendors and methanol producers seeking decarbonization. It equips both parties with tools and preliminary information for integrating clean heat from advanced reactors into novel methanol production processes. The proposed investigation in this report involves a three-step approach: 1. Design of Current and Decarbonized Process Models for Methanol Production. This report initiates process modeling of two novel methanol production pathways, with their overall energy requirements comparative to classical methanol production (see Figure ES1). The two process models provide the foundation for analyzing integration of hermos-electric generation from advanced nuclear reactors. 2. Identification of Coupling Points to Integrate Advanced Reactors. This report investigates the integration with two advanced reactor technologies: light-water reactors (LWRs) and high-temperature gas reactors (HTGRs). The key coupling points between advanced nuclear reactors and the production facilities associated with the two decarbonized methanol process pathways are identified. 3. Preliminary Heat and Electricity Transfer Design from Reactors to Methanol Production Sites. The preliminary designs for piping and instrumentation to transfer heat from the boundary of advanced reactor technology location to the boundary of methanol production site are evaluated within the context of decarbonized pathways. The pipe analysis for heat transfer adheres to relevant codes and specifications from American Society of Mechanical Engineering. A simplified design for transmission of electricity to the industrial site has been provided.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Sub-Doppler Cooling of a Trapped Ion in a Phase-Stable Polarization Gradient

Trapped ions provide a highly controlled platform for quantum sensors, clocks, simulators, and computers, all of which depend on cooling ions close to their motional ground state. Existing methods like Doppler, resolved sideband, and dark resonance cooling balance trade-offs between the final temperature and cooling rate. A traveling polarization gradient has been shown to cool multiple modes quickly and in parallel, but utilizing a stable polarization gradient can achieve lower ion energies, while also allowing tailorable light-matter interactions in the sub-wavelength regime. In this Letter, we demonstrate cooling of a trapped ion below the Doppler limit using a phase-stable polarization gradient created using trap-integrated photonic devices. At an axial frequency of 2⁢𝜋×1.45 MHz we achieve ⟨𝑛⟩=1.56±0.07 in 150 μ⁢s and cooling rates of ∼0.3 quanta/μ⁢s. Here, we examine ion dynamics under different polarization gradient phases, detunings, and intensities, showing reasonable agreement between experimental results and a multilevel model. Cooling is fast and power efficient, with lower average motional Fock state occupation when compared to simulated operation under the corresponding running wave configuration. Our results demonstrate a well-controlled test bed for studying the dynamics of multilevel atomic systems in a phase-stable polarization gradient.

Atom & ion cooling↗

Tandem Predictions for HPC Jobs

At the core of the predictive analytics applied to High Performance Computing (HPC), the most prominent tasks are the prediction of job runtimes and the prediction of job queue times, both of which have the potential for informing HPC users during their every-day decision making. Accurate runtime predictions can help users better choose so-called wallclock times at job submission, decreasing the odds of their jobs waiting in queues longer than necessary. The accurate and timely queue time predictions offered for the available partitions can inform the favorable selection of partitions for running jobs. This potential is well understood as we see in the abundance of research studies that propose solutions for these tasks, including the work published in the last several years. These tasks are seemingly receptive to the Machine Learning (ML) solutions, considering that there is no shortage of training data where HPC centers over time run millions and millions of jobs. However, we study the existing research literature, as well as look for examples in the toolchains supported on the exemplar HPC facilities, and, surprisingly, do not find any practical solutions that are ready to be adopted. We interpret this as a manifestation of the shortage of UX/UI efforts that support HPC analytics and also as a sign that the research has not come to the consensus on solving these tasks. In this study, we aim to shed new light on the long-running task of job queue time prediction by exploring the utility of runtime predictions in improving prediction accuracy and, actually, predicting these two metrics together, in tandem. In other words, we show how runtime predictions become valuable input in the queue time modeling. We challenge the existing approaches to feature engineering for the queue time prediction and describe promising results we obtained for a large dataset of HPC jobs from a supercomputer at the National Renewable Energy Laboratory.

HPC↗

Tandem Predictions for HPC Jobs: Preprint

At the core of the predictive analytics applied to High Performance Computing (HPC), the most prominent tasks are the prediction of job runtimes and the prediction of job queue times, both of which have the potential for informing HPC users during their every-day decision making. Accurate runtime predictions can help users better choose so-called wallclock times at job submission, decreasing the odds of their jobs waiting in queues longer than necessary. The accurate and timely queue time predictions offered for the available partitions can inform the favorable selection of partitions for running jobs. This potential is well understood as we see in the abundance of research studies that propose solutions for these tasks, including the work published in the last several years. These tasks are seemingly receptive to the Machine Learning (ML) solutions, considering that there is no shortage of training data where HPC centers over time run millions and millions of jobs. However, we study the existing research literature, as well as look for examples in the toolchains supported on the exemplar HPC facilities, and, surprisingly, do not find any practical solutions that are ready to be adopted. We interpret this as a manifestation of the shortage of UX/UI efforts that support HPC analytics and also as a sign that the research has not come to the consensus on solving these tasks. In this study, we aim to shed new light on the long-running task of job queue time prediction by exploring the utility of runtime predictions in improving prediction accuracy and, actually, predicting these two metrics together, in tandem. In other words, we show how runtime predictions become valuable input in the queue time modeling. We challenge the existing approaches to feature engineering for the queue time prediction and describe promising results we obtained for a large dataset of HPC jobs from a supercomputer at the National Renewable Energy Laboratory.

97 MATHEMATICS AND COMPUTING↗